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https://hackaday.com/2020/09/10/garbage-can-takes-itself-out/ | Garbage Can Takes Itself Out | Bryan Cockfield | [
"home hacks"
] | [
"garbage",
"home automation",
"image recognition",
"machine learning",
"Nvidia Jetson",
"raspberry pi",
"self-driving",
"Zero W"
] | Home automation is a fine goal but typically remains confined to lights, blinds, and other things that are relatively stationary and/or electrical in nature. There is a challenge there to be certain, but to really step up your home automation game you’ll need to think outside the box.
This automated garbage can that can take itself out
, for example, has all the home automation street cred you’d ever need.
The garbage can moves itself by means of a scooter wheel which has a hub motor inside and is powered by a lithium battery, but the real genius of this project is the electronics controlling everything. A Raspberry Pi Zero W is at the center of the build which controls the motor via a driver board and also receives instructions on when to wheel the garbage can out to the curb from an Nvidia Jetson board. That board is needed because the creator, [Ahad Cove], didn’t want to be bothered to tell his garbage can to take itself out or even schedule it. He instead used machine learning to detect when the garbage truck was headed down the street and instruct the garbage can to roll itself out then.
The only other thing to tie this build together was to get the garage door to open automatically for the garbage can. Luckily, [Ahad]’s garage door opener was already equipped with WiFi and had an available app, unbeknownst to him, which made this a surprisingly easy part of the build. If you have a more rudimentary garage door opener, though,
there are plenty of options available to get it on the internets
. | 12 | 8 | [
{
"comment_id": "6277100",
"author": "Doug Leppard",
"timestamp": "2020-09-10T15:36:50",
"content": "Creative plus you are funny.",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6277102",
"author": "anon",
"timestamp": "2020-09-10T15:40:45",
"conten... | 1,760,373,361.880112 | ||
https://hackaday.com/2020/09/10/3d-printed-thermite-brings-the-heat-and-the-safety/ | 3D-Printed Thermite Brings The Heat, And The Safety | Kristina Panos | [
"3d Printer hacks",
"chemistry hacks",
"Engineering",
"Featured",
"Original Art",
"Slider"
] | [
"aluminium powder",
"energetic material",
"exothermic",
"exothermic welding",
"iron oxide",
"rust",
"solder joints",
"Thermite",
"thermite welding",
"welding in space"
] | Thermites are a double-edged sword. Packing a tremendous energy density, and eager to produce tremendous heat when ignited, thermite is great for welding train tracks. But sometimes you might be looking for a little more
finesse
. A new approach to 3D printing thermites might just be able to tame the beast.
Most of us do our soldering while sitting safely indoors in a comfortable climate. The biggest dangers we’re likely to face are burnt fingertips, forgetting the heat shrink, or accidentally releasing the smoke monster. But outside of our homes and workshops, there’s a lot of extreme joining of metals going on. No matter where it’s done, welding and brazing in the field requires a lot of equipment, some of which is unwieldy and even more difficult to move around in harsh conditions.
Welding railroad tracks with thermite. Image via
YouTube
The utility of brazing is limited by all the complex scaffolding of hardware required to support it. This limiting factor and the discovery of
thermite
led to
exothermic welding
, which uses an energetic material to provide enough heat to melt a filler metal and join the pieces. Energetic materials can store a lot of chemical energy and forcefully release it in a short period of time.
Thermites are made of metal oxide and metal powder, often iron oxide and aluminium. When ignited by a source of high heat, thermite compounds undergo an exothermic reduction-oxidation (redox) reaction as the aluminium reduces the number of electrons in the iron oxide atoms. More heat makes the reaction run faster, generating more heat, and so on. The result is molten iron and aluminium oxide slag.
One of thermite’s first uses was connecting railroad tracks, and it’s still used for that purpose today. Here’s a great video of the thermite welding process in action.
Thermite is dangerous because it produces extremely high heat, but it has a lot of benefits. For one thing, it’s good at joining dissimilar metals. Although
crimped connections are quite reliable
, thermite joints are stronger and can withstand higher voltages. It’s easy to use for making lap joints — just make a solder sandwich with the work pieces, put thermite on top, and ignite it with magnesium ribbon or everyone’s introduction to pyrotechnics — a sparkler.
Thermite is predictably scalable, because the resulting heat output is directly related to the mass of thermite. Traditionally, the thermite reaction is tuned by varying the chemical composition — a little more rust, a little less aluminium powder until it does what you want. This is all fine and good, albeit a bit dangerous, in regular environments, like laying train tracks. In an austere environment like space, the ocean, or the battlefield, the danger of using high heat is much more pronounced.
A Printable, Programmable Heat Source
Printer and printed thermite paste.
Recently, a mechanical engineering PhD student from Vanderbilt University
created a printable 4D thermite paste
that could make exothermic welding much safer, especially in austere environments.
This paste is made from iron oxide, aluminium powder, and gypsum powder. The gypsum powder binds the powders into a printable paste when mixed with water. Even though tartaric acid was added to the water, they had a scant 45 minutes to run it through the printer —
a Discov3ry 1.0 paste extruder hooked up to an Ultimaker 2+
. In their experiments,
the team was successful in using the paste to fuse aluminium and make a simple copper lap joint
.
By printing the paste in precise zigzags and other geometries they call reactive material architectures (RMAs), the team was able to exhibit more control over the thermite reaction. When distributed in these patterns, thermite behaves as a programmable heat source that burns more like a fuse and is inherently safer to store, transport, and use.
Arrows indicate direction of initial reaction, and the red circles highlight new ignition points.
The shapes of these RMAs were chosen to explore the way that each would affect the thermite reaction. The first was a simplified zigzag, an elongated S pattern with hard right angles designed to measure the rate of propagation when one end is ignited.
The complex zigzag pattern above was designed to study the influence of ignited thermite to bridge the gap and ignite new sections that burn perpendicular to the initial reaction. The third architecture — a pair of simple zigzags placed parallel, but at a slight angle — was used to test thermite reaction propagation parallel to the starting reaction. All three architectures were printed and cured in forced-air oven, then ignited and filmed with a high-speed camera outfitted with a welding shade.
There are many joining applications that would benefit from such a controllable heat source. Thermite architectures for underwater or space welding could be designed and printed in advance and then ignited remotely, saving money, equipment expense, and potentially a few lives.
We’ve seen a few thermite hacks in our day, many of which were destructive rather than constructive. Since thermite isn’t something you can just pick up at the store,
start by perusing recipes
. | 15 | 6 | [
{
"comment_id": "6277090",
"author": "Philip Wood",
"timestamp": "2020-09-10T14:38:03",
"content": "I’ve often wondered if you could scale this down:Could one make tiny thermite grains, calibrated to produce enough heat to melt just themselves and a bit extra to bond to a neighbour?(maybe with a bit... | 1,760,373,362.328723 | ||
https://hackaday.com/2020/09/10/cell-phone-signal-booster-gets-teardown-and-demo/ | Cell Phone Signal Booster Gets Teardown And Demo | Donald Papp | [
"Radio Hacks",
"Wireless Hacks"
] | [
"cell phone antenna",
"cell signal booster",
"nextivity",
"wireless",
"wireless booster"
] | Ever wonder what was inside a cell phone booster, or what it is like to set up or use one? If so, [Kerry Wong]’s got you covered with
his teardown of a Cel-Fi Go X Cell Signal Booster by Nextivity
. [Kerry] isn’t just ripping apart a cheap unit for laughs; his house has very poor reception and this unit was a carefully-researched, genuine investment in better 4G connectivity.
The whole setup consists of three different pieces: the amplifier unit pictured above, and two antennas. One is an omnidirectional dome antenna for indoors, and the other is a directional log-periodic dipole array (
LPDA
) antenna for outdoors. Mobile phones connect to the indoor antenna, and the outdoor antenna connects to the distant cell tower. The amplifier unit uses a Bluetooth connection and an app on the mobile phone to manage settings and actively monitor the device, which works well but bizarrely doesn’t seem to employ any kind of password protection or access control whatsoever.
Overall [Kerry] is happy, and reports that his mobile phone enjoys a solid connection throughout his house, something that was simply not possible before. Watch a hands-on of the teardown along with a short demonstration in the video embedded below.
Devices that claim to enhance or boost wireless signals of various kinds seem to attract more than their share of snake oil salesmen, but [Kerry]’s teardown reminds us there are legit hardware offerings (albeit ones with imperfect management app design.) There is also junk out there, like
this antenna that was outperformed by a literal rusty nail
. | 7 | 3 | [
{
"comment_id": "6277071",
"author": "Ren",
"timestamp": "2020-09-10T13:45:23",
"content": "Hey! Hey! Hey!I thought it was Tom Nardi who did the tear downs!B^)",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6277146",
"author": "tonyuk123",
"timestamp":... | 1,760,373,361.928385 | ||
https://hackaday.com/2020/09/10/new-zealand-to-test-wireless-power-transmission/ | New Zealand To Test Wireless Power Transmission | Al Williams | [
"News",
"Wireless Hacks"
] | [
"New Zealand",
"tesla",
"Wireless power"
] | Nikola Tesla wanted to beam power without wires. NASA talked about building power-generating satellites that would do the same thing. But now New Zealand’s second-largest power utility — Powerco — is working with a start-up company to beam energy to remote locations. There have been several news releases, but possibly the most technical detail is from an interview [Loz Blain] did with the
founder of the startup company.
It isn’t really news that you can send radio waves somewhere and convert the signal back into power. Every antenna does that routinely. The question is how efficient is the power transmission and — when the power levels are high — how safe is it? According to [Greg Kushnir], the founder of
Emrod
, the technology is about 70% efficient and uses ISM frequencies.
According to [Kushnir], the technology relies on metamaterials that are very efficient and a beam that sends all the power to the receiver, possibly through some passive relay stations [Kushnir] claims are like lenses and nearly lossless. Reading between the lines, it sounds like a modern take on the MASER with very good receiving antennas.
The relay antennas allow you to send power beyond your line of sight. Apparently, the power density is not enough to be very harmful if you intersect the beam for brief times, but a laser sensor can stop some part of the energy flow if something obstructs the beam.
Is it real? We don’t doubt it is possible. Their existing prototype sends a few watts about 40 meters, which is not a big deal. The new system will transmit “a few kilowatts” for a longer distance. The real question is can you safely operate at power levels that make economic sense based on actual efficiency. Honestly, 70% isn’t that great and even that sounds like it would be difficult to achieve over a long distance. But Powerco must see some promise in the technology, so we’ll wait and see how it goes.
Based on
a tower we saw in Milford, Texas
, we think Tesla had a different method in mind. We did recently see a
Tesla coil-powered bike
, though. | 82 | 21 | [
{
"comment_id": "6277009",
"author": "Scaramouche",
"timestamp": "2020-09-10T08:05:59",
"content": "But what happens if they cross the streams?",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6277017",
"author": "Oli",
"timestamp": "2020-09-10... | 1,760,373,362.104153 | ||
https://hackaday.com/2020/09/09/a-real-working-lego-nes/ | A Real Working Lego NES | Lewin Day | [
"Nintendo Hacks"
] | [
"lego",
"nes",
"nintendo"
] | Lego is an entry into the world of engineering for many a youngster, and an enjoyable pursuit for many more. These days, high quality kits are available to make everything from the Tower of Pisa to Nintendo’s venerated NES console. [TronicsFix] picked up the latter set, and
decided it needed to be fully functional
.
Consisting of 2646 pieces, the official Lego NES is a faithful recreation of the original, albeit at approximately 80% of the size. After building the kit to spec, [TronicsFix] noted that there was no way a cartridge would fit in the slot.
Given this failing, a ground-up rebuild was in order. Starting with the internals from an original NES, [TronicsFix] set about building an appropriately sized base and working from there. Supports were built to mount the various components, with the controller ports being particularly well done, and the video output and power switches being a little more tricky. The many cosmetic pieces from the official kit came in handy here, giving the final product the aesthetic touches it needed to fit the bill.
The final result is an authentic, functional NES in a LEGO case. [TronicsFix] demonstrates as such, showing the console playing Super Mario 3. Nintendo consoles remain a favorite amongst modders;
some going so far as to build fire-breathing creations
. Video after the break.
[Thanks to Mark for the tip!] | 3 | 3 | [
{
"comment_id": "6277052",
"author": "LordNothing",
"timestamp": "2020-09-10T12:02:41",
"content": "i saw this in a lego catalog a couple days ago and said to myself, “its only a matter of time before somone stuffs nintendo guts into it and post it on hack a day”, and here it is.",
"parent_id": ... | 1,760,373,361.831149 | ||
https://hackaday.com/2020/09/09/upgraded-infotainment-options-on-a-14-year-old-mercedes/ | Upgraded Infotainment Options On A 14 Year Old Mercedes | Al Williams | [
"Android Hacks",
"Arduino Hacks",
"Transportation Hacks"
] | [
"android",
"arduino",
"CAN",
"mercedes"
] | It used to be that upgrading a car stereo was fairly simple. There were only a few mechanical sizes and you could find kits to connect power, antennas, and speakers. Now, though, the car stereo has interfaces to steering wheel controls, speed sensors, rear-view cameras, and more. [RND_ASH] was tired of his 14-year-old system so he took an Android head unit, a tablet, and an Arduino, and made
everything work as it was supposed to
.
The key is to interface with the vehicle’s CAN bus which is a sort of local area network for the vehicle. Instead of having lots of wires running everywhere, today’s cars are more likely to have less wiring all shared with many devices.
[RND_ASH] has several videos describing the whole project and we expect there will be some more upcoming. You can see part one, below.
The project also reverse engineers how to display on the tiny screen in the dashboard. The code for the CAN bus interface is on
GitHub
. There’s also a written narrative on what he learned about the Mercedes interface in
a different repository
.
We’ve seen other cars get
similar treatment
, of course. If you want
a gentle introduction to CAN hacking
, we’ve done that, too. | 6 | 5 | [
{
"comment_id": "6276980",
"author": "RF Dude",
"timestamp": "2020-09-10T04:47:01",
"content": "Nice Work! Awesome working display of engine metrics. Must have missed how you provided an amplifier… actually expected to keep the head end or perhaps a new Android head version from China, but with yo... | 1,760,373,361.971914 | ||
https://hackaday.com/2020/09/09/digital-pregnancy-tests-use-leds-to-read-between-the-lines/ | Digital Pregnancy Tests Use LEDs To Read Between The Lines | Kristina Panos | [
"LED Hacks",
"Microcontrollers",
"Misc Hacks"
] | [
"accuracy",
"digital",
"led",
"phototransistor",
"pregnancy",
"pregnancy test"
] | [Foone] saw a tweet a few weeks ago alleging that digital pregnancy tests are a rip-off. Regular, cheap tests have an absorbent strip running the length of the plastic, with one end exposed for collecting urine. A few excruciating minutes later, a little plastic window in the middle will show one line, two lines, or a plus or minus sign depending on the presence of human chorionic gonadotropin (HCG) in the urine.
As it turns out, at least two digital tests out there are the exact same thing, but with more steps
. Instead of a window, they include circuitry that interprets the lines and publishes the result to a little screen in plain English. It can even tell you if you’re doing it wrong by flashing a little RTFM icon.
[Foone]’s teardown reveals a CR1616 coin cell, an 8-bit microcontroller, and a little phototransistor setup that shines LEDs on the strip and reads the incoming light. Unfortunately, the micro is the mask ROM version, so [Foone] can’t
reprogram it to run Doom
.
The original tweet’s author is probably not alone in assuming that digital tests are supposed to be more accurate somehow. We think the accuracy claim is more about removing the frazzled and/or incompetent human variable from the equation. If the test interprets the results for you, then there’s no mistaking the results, which is technically a higher degree of accuracy. But if you’re in doubt, you get a test from a doctor.
There’s been some discussion about the e-waste aspect of these all these tests — that it’s a shame to produce a microcontroller just to pee on it and throw it away. Sure, you could look at it that way, but unlike a lot of e-waste, these are tools. It’s unfortunate that this is the industry’s idea of higher accuracy, but what should we expect? It’s just testing for the presence of a hormone in urine. Interpreting the results is up to the viewer. We should probably be astounded that they got the cost down to two for $7.
Many people choose to wait a while to start spreading the news.
With a Bluetooth-enabled pregnancy test, everyone can find out together
.
Thanks for the
tip
, [Jay]! | 28 | 13 | [
{
"comment_id": "6276936",
"author": "Col. Panek",
"timestamp": "2020-09-09T23:51:22",
"content": "Too many digital gadgets are “Garbage In, Gospel Out”.You can take your BBT with a $10 thermometer (which lasts for years), and chart you temps to prove you’re pregnant (or not).",
"parent_id": nul... | 1,760,373,362.168981 | ||
https://hackaday.com/2020/09/09/third-times-a-charm-for-this-basketball-catching-robot/ | Third Time’s A Charm For This Basketball-Catching Robot | Dan Maloney | [
"Kinect hacks",
"Misc Hacks"
] | [
"backboard",
"basketball",
"cartesian",
"CoreXY",
"Kinect",
"linear algebra",
"tracking"
] | We all know that version one of a project is usually a stinker, at least in retrospect. Sure, it gets the basic idea into concrete form, but all it really does is set the stage for a version two. That’s better, but still not quite there. Version three is where the magic all comes together.
At least that’s how things transpired on [Shane Wighton]’s
quest to build the perfect basketball robot
. His
first version
was a passive backboard that redirected incoming shots based on its paraboloid shape. As cool as the math was that determined the board’s shape, it conspicuously lacked any complicated systems like motors and machine vision — you know, the fun stuff.
Version two
had all these elaborations and grabbed off-target shots a lot better, but still, it had a limited working envelope.
Enter version three, seen in action in the video below. Taking a page from
[Mark Rober]’s playbook
, [Shane] built a wickedly overengineered CoreXY-style robot to cover his shop wall. Everything was built with the lightest possible materials to keep inertia to a minimum and ensure the target ends up in the right place as quickly as possible. [Shane] even figured out how to mount the motor that tilts the backboard on the frame rather than to the carriage. A Kinect does depth-detection duty on the incoming ball — or the builder’s head — and drains pretty much every shot it can reach.
[Shane] has been doing some great work automating away the jobs of pro athletes. In addition to basketball, he has tackled both
golf
and
baseball
, bringing explosive power to each. We’re looking forward to versions two and three on both of those builds as well. | 20 | 9 | [
{
"comment_id": "6276907",
"author": "Hirudinea",
"timestamp": "2020-09-09T21:22:28",
"content": "You know if he could speed this up it would be perfect for batting cages or golfing ranges, just need one ball, catch it and return it to be hit again.",
"parent_id": null,
"depth": 1,
"repl... | 1,760,373,362.46374 | ||
https://hackaday.com/2020/09/09/wooden-tanks-movement-hinges-on-hinges/ | Wooden Tank’s Movement Hinges On Hinges | Brian McEvoy | [
"hardware",
"The Hackaday Prize"
] | [
"2020 Hackaday Prize",
"door hinges",
"model",
"motor",
"paintball",
"remote control",
"scale model",
"tank",
"tank tread",
"turret",
"wwii"
] | When we first looked at this tank, we thought it was pretty cool. The sides are unpainted 1/2″ (12mm) plywood, so it is not flashy. The dimensions came from Google-fu-ing the heck out of the
WWII Hetzer and scaling them to 1:6
. What knocks our socks off is how much [Bret Tallent] made use of parts you would find in a hardware store or bicycle shop. He uses twin motors from electric bikes, and the wheels look like replacement shopping cart wheels. The best part is the treads, which are dozens of hinges fastened with pairs of bolts and nylon-insert nuts. Something is reassuring about knowing that a repair to your baby is no further than a bike ride.
We don’t know what started [Bret] on his path to sidewalk superiority, but we suspect he is cooped up like the rest of us and looking to express himself. Mini-Hetzer is not licensed by Power Wheels and never will be, so it probably won’t turn into a business anytime soon. There is a complete gallery starting with an empty plywood base, and the pictures tell the story of how this yard Jäger got to this point. There are plans to add a paintball gun and streaming video, so we’d advise that you don’t mess with the jack-o-lanterns on his block this year. Give his gallery a view and see if you don’t become inspired to cobble something clever from the hardware store too. Then,
tell us about it
.
Another creative hacker used
wood for their tank body and the treads as well
. If you like your treaded vehicles functional, we have one meant to
taxi small planes over the tarmac
.
The
Hackaday
Prize2020
is Sponsored by: | 28 | 8 | [
{
"comment_id": "6276861",
"author": "Senile Data Systems",
"timestamp": "2020-09-09T18:48:05",
"content": "This treads the fine line between genius and insanity……hehe treads……continues to build on his hamster-powered world domination machine made out of garbage…",
"parent_id": null,
"depth"... | 1,760,373,362.397412 | ||
https://hackaday.com/2020/09/09/autovon-a-phone-system-fit-for-the-military/ | AUTOVON: A Phone System Fit For The Military | Dan Maloney | [
"Hackaday Columns",
"History",
"Original Art",
"Phone Hacks",
"Slider"
] | [
"AUTOVON",
"cold war",
"communications",
"military",
"telephony"
] | It’s a common enough Hollywood trope that we’ve all probably seen it: the general, chest bespangled with medals and ribbons, gazes at a big screen swarming with the phosphor traces of incoming ICBMs, defeatedly picks up the phone and somberly intones, “Get me the president.” We’re left on the edge of our seats as we ponder what it must be like to have to deliver the bad news to the boss, knowing full well that his response will literally light the world on fire.
Scenes like that work because we suspect that real-life versions of it probably played out dozens of times during the Cold War, and likely once or twice since its official conclusion. Such scenes also play into our suspicion that military and political leaders have at their disposal technologies that are vastly superior to what’s available to consumers, chief among them being special communications networks that provide capabilities we could only have dreamed of back then.
As it turns out, the US military did indeed have different and better telephone capabilities during the Cold War than those enjoyed by their civilian counterparts. But as we shall see, the increased capabilities of the network that came to be known as AUTOVON didn’t come so much from better technology, but more from duplicating the existing public switched-telephone network and using good engineering principles, a lot of concrete, and a dash of paranoia to protect it.
Parallel Lines
The world’s militaries have always been early adopters of technology, eager to put the latest scientific and technical advances to use for their dual missions of national defense and projection of political power. This is particularly true of communications technologies, with telegraph, telephone, and radio communications being quickly adopted by militaries between the mid-1800s and the early 20th century, and the US military was certainly no exception.
Most of the connections between US military bases before the 1930s were dedicated lines, with some leveraging of the growing public switched telephone network. But with mobilization for World War II and the subsequent Cold War period leading to a massive expansion of the geographic footprint of the military as well as an increased number of users, military planners saw the folly of relying on the civilian telephone system that was even then experiencing its own growing pains. By the early 1960s it was clear that a phone system dedicated to and specialized for the use of the military was a national security priority.
The designers of what would become known as AUTOVON, or Automatic Voice Network faced a conundrum. The civilian long-distance phone network, which was undergoing a massive buildout at the time, was almost exactly what they needed to provide for the military. But they also knew the limitations of the public telephone network, a system that military planners were certain could collapse under the weight of a panicked populace rushing to the phones to contact loved ones during a national emergency. That precluded leveraging the existing network for the military, so the decision was made to build a second long-haul telephone network, dedicated to military use but mirroring the civilian network in architecture and adding features needed by the military.
Map of AUTOVON stations in the continental US, c. 1970. Note the healthy distance between AUTOVON stations and major population centers. Source:
A Secret Landscape: America’s Cold War Infrastructure
.
Like
the AT&T Long Lines system
that it essentially duplicated, AUTOVON was laid out as a series of long-haul connections that hopscotched across the country. But while the civilian system was designed to hop from city to city and provide service to the maximum number of paying customers, AUTOVON used what was known as “avoidance routing” to build a hardened network.
They weren’t fooling around. Blast doors on the AUTOVON bunker in Pottstown, PA. Source:
Long-Lines.net
.
AUTOVON switching sites were placed safely outside the range of a nuclear attack on any major population center, to ensure their survivability. For instance, Pottstown, Pennsylvania was chosen as an AUTOVON switching site on the transcontinental route from New York to Los Angeles. It was linked to the important naval facilities in Philadelphia, about 35 miles to the southwest, by coaxial lines and microwave links.
Connections between AUTOVON sites were mainly via buried coaxial cables. Much of this cable was directly in the ground rather than encasing it in concrete, as that was deemed sufficient to protect the cable against anything short of a precision attack. Concrete conduits were, however, used to protect sections of the AUTOSEVOCOM, or Automatic Secure Voice Communications network, a parallel military communications network that was designed to pass only encrypted traffic.
Many of the AUTOVON main stations, like the previously mentioned Pottstown station, were equipped with massive underground spaces to house all the telephone switchgear. Burying the buildings was an attempt to protect them from all kinds of disasters, although the details of the structures make it clear what the designers had in mind. The buildings were linked to the surface by shafts with reinforced blast doors, there were massive ventilation fans and filters to provide positive pressure, and diesel generators could provide half a megawatt of power to keep the facility running. Add to that the fact that all the equipment was mounted on shock-absorbing springs and the AUTOVON sites would have been a great place to ride out a nuclear attack.
Flash, Flash, Flash
Aside from its avoidance routing and the reinforced bunkers at its main stations, the AUTOVON network was almost identical to the civilian telephone network of the time. Like its civilian counterpart, it was a circuit-switched network, meaning that it was designed to establish a fixed physical path between sender and receiver and maintain it for as long as required. As such it used much of the same switchgear used by the civilian system, initially using the same crossbar switching gear that had been in use since the 1940s. Later, the crossbar switching gear was swapped for electronic switches, which enabled some of the special features that AUTOVON became known for.
“Get me the president.” An AUTOVON phone in “Hotline Red” with the extra column of Touch-Tone keys. Source:
AUTOVON.org
.
One of the shortcomings of the circuit-switched civilian network is that once a connection is established, it stays connected until one or the other party ends it. Outgoing circuits are a limited resource, though, and once all the circuits are in use, calls cannot go through. In a time of emergency, it wouldn’t do to have a soldier’s call home to his sweetheart prevent a base commander from receiving an order from the Pentagon, and so a system to prioritize and override calls was devised.
Dubbed multilevel precedence and preemption, or MLPP, the scheme provided five levels of precedence. The lowest precedence level was
Routine
, which comprised the bulk of AUTOVON traffic. Above that was
Priority
, followed by
Immediate
,
Flash
, and finally
Flash Override
, theoretically to be used only by those with direct permission from the president. AUTOVON phones accessed the MLPP system using a fourth column of buttons on special 16-key Touch-Tone keypads.
The four extra buttons were used
to assign one of the higher precedence levels to the call by pressing the corresponding key prior to dialing the rest of the number. There was no key for Routine-level calls, since that was the system default.
If a precedence level was assigned to a call and there were no outgoing circuits available, the MLPP system searched for a circuit occupied by a lower precedence call and immediately disconnected it. Call participants would hear a characteristic fast busy tone to let them know they had been bumped. If an outgoing priority call was made to a number that was engaged in a call with lower precedence, the original connection was broken to let the higher precedence call through.
The Packets Are Coming
Construction of AUTOVON began in 1963, and the system went into service at military bases throughout the country in 1966. Three years later, AUTOVON switching stations had been built in Europe, Japan, Korea, the Middle East, and in the Caribbean. Eventually there were about 70 sites in the system, providing the bulk of non-secure communications for the US military and allied forces around the world.
But even as the initial system was still being rolled out, a little project in the Advanced Research Projects Agency was in the works that would plant the seeds of AUTOVON’s eventual demise. The project was
ARPANET
, the first serious packet-switched network, which would lead to the Internet and make almost everything about AUTOVON obsolete. It would still take almost another 30 years for the final pieces of AUTOVON to be retired, though, which is a testament to the staying power not only of circuit-switched networks but also of great engineering. | 59 | 21 | [
{
"comment_id": "6276839",
"author": "Jonathan Bennett",
"timestamp": "2020-09-09T17:24:12",
"content": "I wonder how much AUTOVON infrastructure was up-cycled into what is now the SIPRNet. It’s always fun to look back at how the old military tech worked.",
"parent_id": null,
"depth": 1,
... | 1,760,373,362.26911 | ||
https://hackaday.com/2020/09/09/building-an-affordable-press-for-heat-set-inserts/ | Building An Affordable Press For Heat Set Inserts | Tom Nardi | [
"Tool Hacks"
] | [
"aluminum extrusion",
"heat set inserts",
"press",
"soldering iron"
] | If you’re building mechanical assemblies with 3D printed parts, you’ll quickly realize that driving machine screws into thermoplastic isn’t exactly an ideal solution. It can work in a pinch, but you can easily strip the threads if you crank down too hard. The plastic holes can also get worn down from repeated use, which is a problem if you’re working on something that needs to be taken apart and reassembled frequently. In those situations, using brass heat set inserts gives the fasteners something stronger to bite into.
You can install these inserts by hand, but if you plan on doing a lot of them, a
dedicated press station like the one [Chris Chimienti] recently put together
will save you a lot of aggravation in the long run. In the video after the break he walks viewers through the design and use of the device, which itself relies on a number of 3D printed parts using the very same inserts it’s designed to install.
The spring-loaded arm can slide up and down the extrusion to adjust for height.
To build this tool you’ll need a piece of aluminum extrusion, some smooth rod, a couple springs, and an assortment of fasteners. Nothing that wouldn’t likely be in the parts bin of anyone who’s been tinkering with 3D printers for awhile, though even if you had to buy everything, the Bill of Materials will hardly break the bank. For the base you can use a piece of scrap wood, though [Chris] has opted to make it a storage compartment where he can store the inserts themselves. We really like this approach, but obviously you’ll need to have access to woodworking tools in that case.
Clearly shopping on the top shelf, [Chris] purchased a kit that actually came with a Weller soldering iron and the appropriate tips for the various sized inserts. If you’re like us and just buy the inserts that come in a plastic baggie, you may need to adapt the arm to fit your iron of choice. That said, the idea of having a dedicated iron that you can leave mounted in the press makes a lot of sense to us if you can swing it.
[Joshua Vasquez] wrote up a
phenomenal guide to getting started with heat set inserts
last year that’s an absolute must-read for anyone interested in the concept.
Whether you build a dedicated press
or just push them in freehand, his tips and tricks will help insure you get the best result possible. | 11 | 3 | [
{
"comment_id": "6276823",
"author": "JB",
"timestamp": "2020-09-09T16:10:09",
"content": "I hate to be the grammar nazi here (not really :P ) but“which is a problem if _your_ working on something that needs to be taken apart”",
"parent_id": null,
"depth": 1,
"replies": [
{
... | 1,760,373,362.513959 | ||
https://hackaday.com/2020/09/09/google-turns-android-up-to-11-with-latest-update/ | Google Turns Android Up To 11 With Latest Update | Tom Nardi | [
"Android Hacks",
"Hackaday Columns",
"Slider",
"Software Hacks"
] | [
"android",
"Android 11",
"google",
"mobile device",
"mobile OS",
"update"
] | Just going by the numbers, it’s a pretty safe bet that most Hackaday readers own an Android device. Even if Google’s mobile operating system isn’t running on your primary smartphone, there’s a good chance it’s on your tablet, e-reader, smart TV, car radio, or maybe even your fridge. Android is everywhere, and while the development of this Linux-based OS has been rocky at times, the general consensus is that it seems to have been moving in the right direction over the last few years. Assuming your devices actually get the latest and greatest update, anyway.
So it’s not much of a surprise that Android 11,
which was officially released yesterday
, isn’t a huge update. There’s no fundamental changes in the core OS, because frankly, there’s really not a whole lot that really needs changing. Android has become mature enough that from here on out we’re likely to just see bug fixes and little quality of life improvements. Eventually Google will upset the apple cart (no pun intended) with a completely new mobile OS, but we’re not there yet.
Of course, that’s not to say there aren’t some interesting changes in Android 11. Or more specifically, changes that may actually be of interest to the average Hackaday reader. Let’s take a look at a handful of changes and tweaks worth noting for the more technical crowd.
Improved Availability
Perhaps the biggest change for Android 11 is the fact that more people will actually get it on day one. In the past you’ve always had to have a Pixel or Nexus device to get a fresh build of Android on release, and even then, it was often a staged roll out. But this time around, not only are all the Pixel devices getting it immediately, but so will phones from other manufactures. Well, some of them anyway.
Google says that in addition to their own phones, Android 11 will begin popping up as an update for select OnePlus, Xiaomi, OPPO and realme phones. Obviously there are some very big names missing from that short list of partnered companies, but at least it’s a start. While in general a good thing for the larger Android community, it’s worth noting that this is actually taking something away from the Pixel’s list of elusive features. Combined with the surprisingly low price of the recent Pixel 4a, this could be a sign that Google’s losing interest in trying to develop their own “flagship” phone and would rather focus on pushing the Android ecosystem forward.
Aggressive Permission Controls
Android has always been ahead of the curve in terms of how applications were granted permissions, with even the earliest versions of the operating system indicating what parts of your device each app was designed to interact with. Later, Google added the ability to selectively revoke these permissions after the software was installed. So if you decided down the line that a particular program had no business checking your location or turning on your microphone, you could turn access to those systems off.
Permission screen for the
Hackaday.IO app
.
In Android 11, Google has taken that concept even farther. Now you can chose to grant permissions to an application on a one-time basis instead of permanently. This will be especially useful for software that you might only use once or twice, such as the configuration tool that each new piece of smart home gadgetry invariably requires you to download to complete the initial setup.
What’s more, application permissions will now expire if you haven’t used the application in awhile. Google isn’t clear on how long it actually takes, but eventually the OS will reset all the permissions for an application that hasn’t been started recently.
The next time you open the application, it will ask you to confirm the permissions it requires as if it had just been installed. On the whole, this will help reduce the attack surface of your device, meaning that only your most commonly used (and presumably, most trusted) applications will have active permissions at any given time.
Centralized Smart Home Devices
Speaking of those per-device applications that have regrettably become the norm with smart home products, Android 11 attempts to improve the situation somewhat by automatically collecting all the smart gadgets detected on the network and putting their controls on a single screen. When pressing the power button, you’re now greeted with a configurable array of the smart home products that Android has sniffed out. With just a tap on this screen, you can turn things on and off without having to dive into each gadget’s respective applications.
Naturally, there are some caveats. You’ll still need to complete the initial setup of new products with their manufacturer-supplied applications, perhaps making use of that one-time permission feature, and of course the devices need to be supported by Google’s own ecosystem for them to show up.
Native Screen Recording
This one might not seem like a big deal at first glance, especially since there’s already been plenty of screen recording applications available for Android. But now the feature is baked right into the OS without the need to download anything separately.
Both your device’s audio and video can be recorded with a tap of the “Screen Record” icon in the quick settings menu. There’s even an option that will toggle visible screen touches, so that viewers seeing the video will know where you were tapping.
With more and more projects including a mobile phone component, this feature could be a boon for documentation. If you’re using an Android application or even a mobile-targeted website as part of your project, the native screen recording capability and tap visualization will let you easily produce step-by-step instructions and walk-through videos without having to resort to some ad-ridden app from the Play Store.
Videos created with the built-in screen recorder are dropped in the “Movies” directory of your device’s storage partition, and according to
ffmpeg
are encoded as exceptionally high bitrate (~27,000 kbps) H264.
Exposure Notification API Changes
As we covered in the past,
Google has been working behind the scenes to push a new contact tracing API
into the majority of Android devices in response to the COVID-19 pandemic. In Android 10 and below this was silently distributed through a Google Play Services update, and required your device’s Location service to be enabled. But on Android 11, things are a little different.
The Exposure Notification API is now fully integrated into the OS and is ready to go as soon as the device boots up. Further, Google says they have tweaked how the API works so that it
no longer allows apps to request your Location data
. In turn, that means it doesn’t require the Location service to be enabled. On the positive side, it makes good on the privacy promises of the API framework. Undoubtedly some will see this as a negative, as it makes selectively disabling contact tracing more difficult.
While there’s still plenty of
debate about how effective these systems are
, it seems Google isn’t giving up the fight.
Android or Bust
While there might not be any huge changes to the OS in Android 11, it does have enough little tweaks that seem like they add up to a solid update. Of course it’s too soon to see what the downsides are, as it will take a week or so before any particularly egregious bugs bubble their way to the surface. In that case, perhaps being in the second or third wave of users to get the latest update isn’t such a bad thing.
At this point, we’re all pretty much stuck with Android. The only serious alternative is iOS, and we won’t even get into why that system is at odds with the hacker ethos. While we’d all like to see a fully free and open source mobile operating system (Linux based or otherwise), the reality is that there just aren’t any serious contenders on the horizon.
As impressive as projects like postmarketOS are
, nobody is under the delusion that they are going to eat up any appreciable market share.
So if we’ve got to live with Android for the foreseeable future, let’s at least hope Google stays the course and produces more updates like this one. It might not be perfect, but it’s getting better. | 32 | 14 | [
{
"comment_id": "6276800",
"author": "zoobab",
"timestamp": "2020-09-09T14:27:41",
"content": "“As we covered in the past, Google has been working behind the scenes to push a new contact tracing API into the majority of Android devices in response to the COVID-19 pandemic.”Only fools would trust Goo... | 1,760,373,362.596655 | ||
https://hackaday.com/2020/09/08/size-does-matter-when-it-comes-to-sd-cards/ | Size Does Matter When It Comes To SD Cards | Lewin Day | [
"computer hacks",
"Featured",
"Interest",
"Original Art",
"Slider"
] | [
"microsd",
"sd card",
"storage"
] | The SD card first burst onto the scene in 1999, with cards boasting storage capacities up to 64 MB hitting store shelves in the first quarter of 2000. Over the years, sizes slowly crept up as our thirst for more storage continued to grow. Fast forward to today, and the biggest microSD cards pack up to a whopping 1 TB into a package smaller than the average postage stamp.
However, getting to this point has required many subtle changes over the years. This can cause havoc for users trying to use the latest cards in older devices. To find out why, we need to take a look under the hood at how SD cards deal with storage capacity.
Initial Problems
A rare 4 GB card produced piror to the ratification of SDHC. Compatibility of such cards is limited, as they operate outside of both the earlier or later standard. Image credit:
Wirepath
The first issues began to appear with the SD standard as cards crossed the 1 GB barrier. Storage in an SD card is determined by the number of clusters, how many blocks there are per cluster, and how many bytes there are per block. This data is read out of the Card Specific Data, or CSD register, by the host. The CSD contains two fields, C_SIZE, and C_SIZE_MULT, which designated the number of clusters and number of blocks per cluster respectively.
The 1.00 standard allowed a maximum of 4096 clusters and up to 512 blocks per cluster, while assuming block size was 512 bytes per block. 4096 clusters multiplied by 512 blocks per cluster, multiplied by 512 bytes per block, gives a card with 1 GB storage. At this level, there were no major compatibility issues.
The formula used to calculate SD card capacity in version 1.01 of the standard.
The 1.01 standard made a seemingly minor change – allowing the block size to be 512, 1024, or even 2048 bytes per block. An additional field was added to designate the maximum block length in the CSD. Maximum length,
as designed by READ_BL_LEN and WRITE_BL_LEN in the official standard
, could be set to 9, 10, or 11. This designates the maximum block size as 512 bytes (default), 1024 bytes, or 2048 bytes, allowing for maximum card sizes of 1 GB, 2 GB, or 4 GB respectively. Despite the standard occasionally mentioning maximum block sizes of 2048 bytes, officially, the original SD standard tops out at 2 GB. This may have been largely due to the SD card primarily being intended for use with the FAT16 file system,
which itself topped out at a 2 GB limit in conventional use.
Suddenly, compatibility issues existed. Earlier hosts that weren’t aware of variable block lengths would not recognise the greater storage available on the newer cards. This was especially problematic with some edge cases that tried to make 4 GB cards work. Often, very early readers that ignored the READ_BL_LEN field would report 2 GB and rare 4 GB cards as 1 GB, noting the correct number of clusters and blocks but unable to recognise the extended block lengths.
Thankfully, this was still early in the SD card era, and larger cards weren’t in mainstream use just yet. However, with the standard hitting a solid size barrier at 4 GB due to the 32-bit addressing scheme, further changes were around the corner.
Later Barriers
2006 brought about version 2.00 of the SD specification. Heralding in the SDHC standard, it promised card sizes up to a full 32GB. Technically, SDHC was treated as a new standard, meaning all cards above 2GB should be SDHC, while cards 2GB and below should remain implemented as per the existing SD standard.
The formula for calculating capacity in SDHC and SDXC cards.
To achieve these larger sizes, the CSD register was entirely reworked for SDHC cards. The main C_SIZE field was expanded to 22 bits, indicating the number of clusters, while C_SIZE_MULT was dropped, with the standard assuming a size of 1024 blocks per cluster. The field indicating block length – READ_BL_LEN – is kept, but locked to a value of 9, mandating a fixed size of 512 bytes per block. Two formerly reserved bits are used to indicate card type to the host, with standard SD cards using a value of 0, with a 1 indicating SDHC format (or later, SDXC). Sharp readers will note that this could allow for capacities up to 2 TB. However, the SDHC standard officially stops at 32 GB. SDHC also mandates the use of FAT32 by default, giving the cards a hard 4 GB size limit per file. In practice, this is readily noticable when shooting long videos at high quality on an SDHC card. Cameras will either create multiple files, or stop recording entirely when hitting the 4 GB file limit.
SDXC allows for cards up to 2TB in size, with cards maxing this out almost on the market. In 2018, the SDUC standard was announced, which will allow for sizes up to 128TB.
To go beyond this level, the SDXC standard accounts for cards greater than 32 GB, up to 2 TB in size. The CSD register was already capable of dealing with capacities up to this level, so no changes were required. Instead, the main change was the use of the
exFAT file system
. Created by Microsoft especially for flash memory devices, it avoids the restrictive 4 GB file size limit of FAT32 and avoids the higher overheads of file systems like NTFS.
Current cards are available up to 1 TB, close to maxing out the SDXC specification. When the spec was announced 11 years ago,
Wired reported that 2 TB cards were “coming soon”
, which in hindsight may have been jumping the gun a bit. Regardless,
the next standard, SDUC, will support cards up to 128 TB in size
. It’s highly likely that another break in compatibility will be required, as the current capacity registers in the SDXC spec are already maxed out. We may not find out until the specification is made available to the wider public in coming years.
Where The Problems Lie
The most obvious compatibility problems lie at the major barriers between generations of SD cards. The 1 GB barrier between 1.00 and 1.01, the 2 GB barrier between SD and SDHC, and the 32GB barrier between SDHC and SDXC. In most embedded hardware, these are hard barriers that simply require the correct size card or else they won’t work at all. However, in the case of desktop computers, there is sometimes more leeway. As an example,
SanDisk claim that PC card readers designed to handle SDHC should be able to read SDXC cards as well
, as long as the hosting OS also supports exFAT. This is unsurprising, given the similar nature of the standards at the low level.
A handy guide to which cards are compatible with which readers. In practice, individual hosts may have their own confusing limitations.
Thankfully, newer readers are backwards compatible with older cards, but the reverse is rarely true. However, workarounds do exist that can allow power users to make odd combinations play nice. For example, formatting SDXC cards with FAT32 generally allows them to be used in place of SDHC cards. Additionally, formatting SDHC cards with FAT16 may allow them to be used in place of standard SD cards, albeit without access to their full storage capacity.
These workarounds are far from a sure thing, though. Many devices exist that have their own baked-in limits, from quirks in their own hardware and software.
A particularly relevant example is the Raspberry Pi.
All models except for the 3A+, 3B+ and Compute Module 3+ are limited to SD cards below 256 GB, due to a bug in the System-on-Chip of earlier models. Fundamentally, for some hardware, the best approach can be to research what works and what doesn’t, and be led by the knowledge of the community. Failing that, buy a bunch of cards, write down what works and what doesn’t, and share the results for others to see.
Unfortunately, the problem isn’t going away anytime soon. If anything, as card sizes continue to increase, older hardware may be left behind as it becomes difficult to impossible to source compatible cards in smaller capacities that are no longer economical for companies to make. Already, it’s difficult to impossible to source new cards 2 GB and below. Expect complicated emulated solutions to emerge for important edge-case hardware,
in the same way we use SD cards to emulate defunct SCSI disks today. | 54 | 19 | [
{
"comment_id": "6276574",
"author": "Ostracus",
"timestamp": "2020-09-08T17:25:05",
"content": "In other words when one doesn’t design for trends. How many design for a future when hardware becomes, less capable over time?",
"parent_id": null,
"depth": 1,
"replies": [
{
"c... | 1,760,373,362.857086 | ||
https://hackaday.com/2020/09/08/designing-hardware-challenges-hack-chat/ | Designing Hardware Challenges Hack Chat | Dan Maloney | [
"Hackaday Columns"
] | [
"Hack Chat"
] | Join us on Wednesday, September 9 at noon Pacific for the
Designing Hardware Challenges Hack Chat
with Michelle Thompson!
Michelle is deeply involved in designing the virtual CTF challenge for
this month’s GNU Radio Conference
. Her experience includes dreaming up both in-person and virtual “Capture the Flag” style challenges that span both hardware and software. It’s fun to compete and a powerful way to learn, but how do you choose the hardware and dial-in the scope and difficulty for each part of the challenge? Join us for the chat as Michelle walks through how she builds great challenges.
Our Hack Chats are live community events in the
Hackaday.io Hack Chat group messaging
. This week we’ll be sitting down on Wednesday, September 9 at 12:00 PM Pacific time. If time zones baffle you as much as us, we have
a handy time zone converter
.
Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about. | 1 | 1 | [
{
"comment_id": "6276573",
"author": "K-WW",
"timestamp": "2020-09-08T17:22:33",
"content": "Love the “Incredible Machine” graphic",
"parent_id": null,
"depth": 1,
"replies": []
}
] | 1,760,373,362.954246 | ||
https://hackaday.com/2020/09/08/a-backlit-calendar-for-all-eternity/ | A Backlit Calendar For All Eternity | Moritz v. Sivers | [
"clock hacks",
"cnc hacks"
] | [
"acrylic",
"cnc",
"perpetual calendar"
] | The advantage of the irregularities in the Gregorian calendar combined with the seven-day week is that they provide a constant source of yearly revenue for the paper calendar industry. Long before sustainability became a trending topic, people invented reusable, perpetual calendars, but the non-digital versions of these are sometimes complicated tables that are hard to interpret. [andrei.erdei] created an
automated perpetual calendar
that is mostly hardware but uses some digital tricks to overcome these problems.
The calendar consists of sandwiched panels of smoked acrylic which are backlit by some strips of WS2812Bs. Although the panels could have been processed with a laser cutter, [andrei.erdei] used a CNC which gave him the possibility to mill some grooves in the back panel to hold the LED strips. The stencil for the numbers was simply printed out on paper and the background made opaque by printing several times over the same piece of paper. The electronics consist of an ESP8266 which takes the date from an NTP server and lights up the corresponding LEDs in different colors for weekdays and weekends.
The classic version of this type of perpetual calendar uses a
sliding frame
but we have also seen completely different versions based on
moving gears
.
Video after the break. | 7 | 5 | [
{
"comment_id": "6276541",
"author": "Ren",
"timestamp": "2020-09-08T15:36:34",
"content": "From the title, I thought the backlighting was for “all of eternity”, therefore, I was assuming it was backlit by ambient light.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comm... | 1,760,373,363.004118 | ||
https://hackaday.com/2020/09/08/teardown-mini-gps-jammer/ | Teardown: Mini GPS Jammer | Tom Nardi | [
"Featured",
"Radio Hacks",
"Slider",
"Teardown"
] | [
"555 timer",
"gps",
"jammer",
"NE555",
"RTL-SDR",
"vco"
] | If you spend enough time trolling eBay for interesting electronic devices to take apart, you’re bound to start seeing suggestions for some questionable gadgets. Which is how I recently became aware of these tiny GPS jammers that plug directly into an automotive 12 V outlet. Shipped to your door for under $10 USD, it seemed like a perfect device to rip open in the name of science.
Now, you might be wondering what legitimate uses such a device might have. Well, as far as I’m aware, there aren’t any. The only reason you’d want to jam GPS signals in and around a vehicle is if you’re trying to get away with something you shouldn’t be doing. Maybe you’re out driving a tracked company car and want to enjoy a quick two hour nap in a parking lot, or perhaps you’re looking to disable the integrated GPS on the car you just stole long enough for you to take it to the chop shop. You know, as one does.
But we won’t dwell on the potentially nefarious reasons that this device exists. Hackers have never been too choosy about the devices they investigate and experiment with, and there’s no reason we should start now. Instead, let’s take this piece of gray-area hardware for a test drive and see what makes it tick.
Can You Hear Me Now?
While the GPS constellation average altitude of 20,200 km (12,550 miles) might not be quite as high up as communication satellites in geosynchronous orbit, they’re still pretty far away. With this incredible distance in mind, and given the size of the antenna on most GPS-equipped devices, it’s no wonder that the received signal is very weak. So weak, in fact, that it’s generally below the noise floor. Only with clever algorithms and a dash of wizardry can your phone turn this whisper from the stars into anything resembling useful information.
When viewed by an RTL-SDR, the GPS signal is like a needle in a haystack.
It’s this fragility that makes these sort of low-cost jammers possible. It doesn’t take much to overpower the legitimate signal. Keep in mind that a device like this isn’t trying to mimic a GPS satellite, it’s simply broadcasting out enough loud nonsense that the real satellite can no longer be heard.
With the jammer powered up, we can clearly see how the already meager signal is absolutely obliterated by the patterns being broadcast by the device.
With the jammer switched on, the signal becomes a needle in a haystack of needles.
There’s simply no contest; the legitimate signal is tens of thousands of kilometers away, and this thing is screaming its head off at arm’s reach. I didn’t test the range of this device, mainly because I didn’t want to have it powered up for any longer than necessary, but it’s certainly capable of doing the deed at several meters at least.
Betrayed By an Old Friend
Now that we’ve
broken federal law for a few minutes
by operating this device (seriously, don’t buy one of these) and verified that the dastardly thing does what it’s advertised to do, the only thing left to do is open it up and figure out how it works. For the $8 I paid for this unit I certainly wasn’t expecting a lot inside, but even still, it’s fascinating to see just how easy it is to cause so much trouble.
After years of losing work to the Arduino, the 555 timer has fallen in with the wrong crowd.
On one side of the PCB we can see there are only two major components, a 78M05 regulator to step the vehicle’s 12 volts down to 5 volts, and the hacker’s old friend, the NE555 timer. It’s a shame to see that it takes a teardown of an illegal jammer before we see one of the most iconic ICs in the history of electronics, but there you have it.
Still, unless you’re looking to jam an AM radio, a 555 isn’t going to cut it. Flipping the board over, we get our first glance at the real trouble maker.
RF Witchcraft in a Can
Clearly this component, labeled 13BA A041, is the star of the show. But what is it? While I wasn’t able to find a datasheet for this specific model, what we’re looking at is a microwave voltage-controlled oscillator (VCO). The visible top plate is actually a metallic shield, and with a bit of persuasion, we can look inside to see the incredible array of components that have been packed into the 9 mm x 7 mm area.
The basic theory of operation here is that the VCO’s control pin (labeled VC on the silkscreen) is connected to the output of the 555 timer on the other side of the board. The signal coming from the 555 modulates the output of the VCO, causing the noise we see centered on the 1,575 MHz GPS frequency.
With the scope connected to the VC pin, we can see the 133 KHz sawtooth signal being produced by the 555 timer. If you were to adjust this signal you could potentially shift around the frequency range that the jammer operates on, though without a datasheet for the VCO, it’s difficult to say how far you could push it in either direction. But since these were presumably the cheapest components available, probably not very far.
It’s also worth taking a close look at the small four pin device at the top of the board labeled Q6. Located directly in the path of the high frequency signal as it passes from the VCO to the center pin of the antenna connector, this would be a logical place to put an amplifier. Though it may also be some kind of a diode to protect the electronics from anything that’s picked up from the antenna.
An Unfortunate Surprise
Part of me assumed that the Mini GPS Jammer just wouldn’t work, or at least, it would work so poorly as to not be an issue. But no, in a break from tradition, a cheap imported device from eBay managed to actually exceed all of my expectations.
Not that I’m happy about it. Sure the
information to build a jammer like this
has been out in the wild for years, but you still needed to have the wherewithal to actually source the parts and assemble it. With such a low bar for entry, this device is clearly quite dangerous in the wrong hands. While a WiFi or cellular jammer would perhaps present a more immediate threat, this is still not technology that anyone wants to see proliferate. | 142 | 36 | [
{
"comment_id": "6276505",
"author": "Per Jensen",
"timestamp": "2020-09-08T14:11:01",
"content": "The 4-pin device is certainly an amplifier. One of the pins are having DC injected trough an inductor that makes sure that DC can get in, but the RF isn’t shunted to the supply.",
"parent_id": null... | 1,760,373,363.250804 | ||
https://hackaday.com/2020/09/08/esp32-hash-monster-fills-pockets-with-packets/ | ESP32 Hash Monster Fills Pockets With Packets | Tom Nardi | [
"Microcontrollers",
"Security Hacks",
"Software Hacks"
] | [
"encryption",
"ESP32",
"M5Stack",
"penetration testing",
"wifi"
] | Unless you’re reading this from the middle of the ocean or deep in the forest, it’s a pretty safe bet there’s WiFi packets zipping all around you right now. Capturing them is just a matter of having the right hardware and software, and from there, you can get to work on cracking the key used to encrypt them. While such things can obviously have nefarious connotations, there are certainly legitimate reasons for auditing the strength of the wireless networks in the area.
It might not have the computational horsepower to crack any encryption itself, but the ESP32 M5Stack is more than up to the task of capturing WiFi packets if you install
the Hash Monster firmware developed by [G4lile0]
. Even if you don’t intend on taking things farther, this project makes finding WiFi access points and grabbing their packets a fascinating diversion with the addition of a few graphs and an animated character (the eponymous monster itself) that feeds on all those invisible 1s and 0s in the air.
There’s some excellent documentation floating around
that shows you the start to finish process of popping open a WiFi network with the help of Hash Monster, but that’s only the beginning of what’s possible with this gadget. A quick search
uncovers a number of software projects
that make use of the specific advantages of the M5Stack compared to more traditional ESP32 boards, namely the built-in screen, buttons, and battery. We’ve even seen it used in a few builds here on Hackaday,
such as this DIY thermal camera
and
custom shipboard computer system
.
[Thanks to Manuel for the tip.] | 4 | 3 | [
{
"comment_id": "6276502",
"author": "wizardpc",
"timestamp": "2020-09-08T13:48:59",
"content": "This would be great to get going on the LilyGo t-watch 2020",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6276578",
"author": "GenTooMan",
"timestamp": "2... | 1,760,373,362.907496 | ||
https://hackaday.com/2020/09/08/a-gaming-mouse-with-recoil-feedback/ | A Gaming Mouse With Recoil Feedback | Lewin Day | [
"Peripherals Hacks"
] | [
"haptic",
"haptic feedback",
"haptics",
"mouse"
] | Rumble first hit the gaming mainstream back in the mid-1990s, and has become de rigeur for console players using gamepads ever since. It’s less prevalent on the PC, because most players rely on keyboards and mice that are rumble-free. However, innovation is possible,
and [ilge] put together a modified mouse for shooters that has an excellent recoil feedback device.
The feedback effect is run by an Arduino, which receives serial data from a Python program running on the host computer. When the mouse is clicked, the Python program notifies the Arduino, which then fires a bank of four solenoids repeatedly back-and-forth to generate the feedback effect. The solenoids are triggered by a relay, which is an easy way to switch such a load, though we suspect it may not hold up well over time due to the rapid fire rate and the likelihood of spark damage over time from high inrush current to the solenoids.
It’s a simple build that nonetheless adds a great haptic feedback effect to the otherwise humble computer mouse. While we don’t expect to see pros using the device anytime soon, it’s a great concept that does add to the shooter experience. Similar hardware could likely be put to great use in a VR context, too.
The state of the art of haptic technology continues to move at a rapid pace
, and we can’t wait to see what comes next. Video after the break. | 21 | 14 | [
{
"comment_id": "6276461",
"author": "xztraz",
"timestamp": "2020-09-08T08:16:58",
"content": "Logitech made a tactile feedback mouse many years ago. Used to have one. Concept was fun but not very usefull.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "62765... | 1,760,373,363.058392 | ||
https://hackaday.com/2020/09/07/the-floppy-disk-as-a-portable-music-format/ | The Floppy Disk As A Portable Music Format | Jenny List | [
"digital audio hacks"
] | [
"3.5\" floppy disk",
"floppy disk",
"music player"
] | We remember the floppy disk as the storage medium most of us used two decades or more ago, limited in capacity and susceptible to data loss. It found its way into a few unexpected uses such as Sony’s Mavica line of digital cameras, but outside those who maintain and use older equipment it’s now ancient history.
Seemingly not for [Terence Eden] though, who has made
a portable audio player that uses a floppy disk as its storage medium
. It came about with the realization that half an hour of extremely compressed audio could be squeezed onto a standard 3.5 inch floppy, and then that the Beatles’
A Hard Day’s Night
album comes in at only a shade over that time. With some nifty manipulation of the compression command line and the judicious removal of some unnecessary metadata, the album can fit on a floppy in equivalent quality to the AM radio fans would have heard it over back in 1964.
The player would have been a major undertaking when the floppy was king, but in 2020 it’s simply a USB floppy drive, a Raspberry Pi, and a battery pack. He’s given us the full instructions, and no doubt a more permanent version could be built with a 3D-printed case.
We’re fascinated by the
recent trend of storing audio on floppy disks
, but despite the hipster vibe, we doubt the idea will catch on. It’s not the first floppy-based player we’ve seen, but
the previous one was more of a fake player
. | 27 | 15 | [
{
"comment_id": "6276451",
"author": "Jan",
"timestamp": "2020-09-08T06:51:09",
"content": "Cool project!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6276454",
"author": "Jens Ma",
"timestamp": "2020-09-08T07:14:55",
"content": "So a usb floppy ... | 1,760,373,363.368714 | ||
https://hackaday.com/2020/09/09/tesla-coil-electric-bikes-is-wireless/ | Tesla Coil Electric Bike Is Wireless | Bryan Cockfield | [
"Transportation Hacks"
] | [
"ebike",
"electric bike",
"electric field",
"lightning lab",
"tesla coil",
"Wireless power"
] | Electric bikes, and really all electric vehicles, have one major downside: the weight and cost of batteries. Even with lithium, battery packs for ebikes can easily weigh more than the bike itself and cost almost as much. But having to deal with this shortcoming could be a thing of the past thanks to [LightningOnDemand]’s recent creation. Of course, this would rely on a vast infrastructure of Tesla coils since that’s how this bike receives the power it needs to run its electric motor.
The Tesla coil used for the demonstration is no slouch, either. It’s part of the Nevada Lightning Laboratory and can
pack a serious punch
(PDF warning). To receive the electrical energy from the coil, the bike (actually a tricycle) uses a metal “umbrella” of sorts which then sends the energy to the electric motor. The bike drags a chain behind itself in order to have a ground point for the electricity to complete its circuit. There is limited range, though, and the Tesla coil will start ionizing paths to the ground if the bike travels too far away.
While we can’t realistically expect Tesla’s idea of worldwide, free, wireless electricity to power our bicycles anytime soon, it is interesting to see his work proven out, even if its on a small scale like this. Of course, it doesn’t take a research laboratory to start working with Tesla coils.
This one is built out of common household parts
and still gets the voltages required to create the signature effects of a Tesla coil.
Thanks to [Adam] for the tip! | 28 | 14 | [
{
"comment_id": "6276762",
"author": "Thorsten",
"timestamp": "2020-09-09T12:15:41",
"content": "I think the main question is how much power is needed to make the trike driving. The coil looks quite big and consumes probably a lot of energy. If the efficiency of the whole system is only a few percen... | 1,760,373,363.311354 | ||
https://hackaday.com/2020/09/09/paper-keyboard-is-self-powered/ | Paper Keyboard Is Self-Powered | Al Williams | [
"News"
] | [
"paper",
"purdue",
"triboelectric"
] | Building a keyboard isn’t a big project these days. Controller chips and boards are readily available, switches are easy to find, and a 3D printer can do a lot of what used to be the hard parts. But engineers at Purdue have printed a self-powered
Bluetooth keyboard on an ordinary sheet of paper
. You can see videos of the keyboards at work below.
The keyboards work by coating paper with a highly fluorinated coating that repels water, oil, and dust. Special inks print triboelectric circuits so that pressing your finger on a particular part of the paper generates electricity. We were skeptical that the Bluetooth part is self-powered, although maybe it is possible if you have some very low-power electronics or you manage the power generated very carefully.
Conductive nanoparticles are involved and — supposedly — they keyboards cost less than $0.25 to print. We presume that is after the fixed costs of setting everything up.
What would you use this for? It seems like paper isn’t going to be a good choice for long-term durable goods like laptops or cell phones. We can imagine a deli menu with buttons on it, perhaps, but it seems like it will be a while before that’s truly practical.
Still, if it is as robust as it looks, it should be interesting for something. We just aren’t sure what yet.
Triboelectricity
from key strikes probably isn’t going to run much electronics for very long, but it is fine for energizing some wires for a keypress. This isn’t the first
paper generator
we’ve seen, oddly enough. | 12 | 7 | [
{
"comment_id": "6276727",
"author": "Gerry SWEENEY",
"timestamp": "2020-09-09T08:12:02",
"content": "Err, yeah not sure about that…",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6276732",
"author": "Łukasz",
"timestamp": "2020-09-09T08:37:19",
"c... | 1,760,373,363.416367 | ||
https://hackaday.com/2020/09/08/lego-delivers-corvette-experience-on-a-budget/ | LEGO Delivers Corvette Experience On A Budget | Tom Nardi | [
"Raspberry Pi",
"Toy Hacks"
] | [
"dashboard",
"dyno",
"lego",
"model",
"motorized",
"sports car",
"transmission"
] | Many dream of tooling around in a high performance sports car, but the cost of owning, maintaining, and insuring one of them make it a difficult proposition. While this
LEGO version of the Corvette ZR1 might not be
exactly
like the real thing
, it’s 4-speed manual and electronic gauge cluster can give you a taste of the supercar lifestyle without having to taken out a second mortgage.
Working through the gears.
Built by [HyperBlue], this desktop speedster has more going on under the hood (or more accurately, the roof) than you might expect. While it looks pretty unassuming from the outside, once the top is lifted, you can see all the additional components that have been packed in to motorize it. The functional gearbox takes up almost the entire interior of the car, but it’s not like you were going to be able to fit in there anyway.
But the motorized car is really only half of the project. [HyperBlue] has built a chassis dynamometer for his plastic ride that not only allows you to “start” the engine with realistic sights and sounds (recorded from an actual GM LT1 V8 engine), but put the mini ‘Vette through its paces. With a virtual dashboard powered by the Raspberry Pi, you can see various stats about the vehicle such as throttle position, RPM, and calculated scale speed; providing a real-world demonstration of how the transmission operates.
While a LEGO sports car might not be
quite as exciting as getting yourself a real project car
, there’s something to be said for being able to rebuild your transmission without getting your hands dirty. | 5 | 3 | [
{
"comment_id": "6276720",
"author": "RandyKC",
"timestamp": "2020-09-09T07:44:15",
"content": "Insurance would be cheaper.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6276737",
"author": "Kayla T.",
"timestamp": "2020-09-09T08:59:27",
... | 1,760,373,363.465524 | ||
https://hackaday.com/2020/09/08/tutorial-for-setting-up-raspberry-pi-for-ham-radio-use/ | Tutorial For Setting Up Raspberry Pi For Ham Radio Use | Al Williams | [
"Radio Hacks",
"Raspberry Pi"
] | [
"ham radio",
"raspberry pi",
"sdr"
] | There was a time when a ham radio set up sported many dials and switches and probably quite a few boxes as well. Computers have changed all that. Some transceivers now have just a few buttons or are even totally computer-controlled. Where a ham, at one time, might have a TeleType machine, a slow-scan TV monitor, and a fax printer for receiving satellite images, now that can all be on a single computer which can
even be a Raspberry Pi
. [F4GOH] has a post that takes you from the fundamentals to installing everything from an SDR to many common ham programs for digital modes, APRS, SSTV, and more. You can download the seven-part tutorial as separate PDF files, too.
Even if you aren’t a ham, you might find some of the software interesting. OpenWebRX lets you listen to your software defined radio on the road. You can use other software to pick up weather satellite data.
If you are a seasoned Linux user, you won’t need some of the early material. But you will find some good notes on how to use the ham-specific software and get a good overview of what is possible.
Ham radio has changed a great deal. If you think of it as people with noisy large radios, you might be surprised. The hobby is big enough that you’ll find everything from people talking on tiny radios around the world using a hybrid of radio and Internet connectivity, to people bouncing signals off the moon or using ham radio satellites.
[Dan Maloney] has talked about how to
get started in ham radio
for under $50. Then again, you might need another $50 for the Raspberry Pi. Of course, there are plenty of opportunities to
hack the gear
. | 9 | 6 | [
{
"comment_id": "6276697",
"author": "N0LSD",
"timestamp": "2020-09-09T04:42:16",
"content": "If one is specifically involved with Amateur radio, KM4ACK has an excellent ham radio Pi image – do a YouTube search on his callsign. He’s actually coded key features into his build – not just integrated a... | 1,760,373,363.508146 | ||
https://hackaday.com/2020/09/08/measure-1024-times-cut-once/ | Measure 1024 Times, Cut Once | Brian McEvoy | [
"Tool Hacks"
] | [
"automated saw",
"cnc",
"cnc table saw",
"rebuild",
"retrofit",
"saw",
"table saw"
] | Typically, someone’s first venture into coding doesn’t get a lot of attention. Then again, most people don’t program a
CNC table saw
right out of the gate. [Jeremy Fielding] wasn’t enticed with “Blink” or “Hello, world,” and took the path less traveled. He tackled I/O, UX, and motion in a single project, which we would equate to climbing K2 as a way to get into hiking. The Python code was over 500 lines, so we feel comfortable calling him an over-achiever.
The project started after he replaced the fence on his saw and wondered if he could automate it, and that was his jumping-on point, but he didn’t stop there. He automated the blade height and angle with stepper motors, so the only feedback is limit switches to keep it from running into itself. The brains are a Raspberry Pi that uses the GPIO for everything. There is a manual mode so he can use the hand cranks to make adjustments like an ordinary saw, but he loses tracking there. His engineering background shines through in his spartan touchscreen application and robust 3D model. The built-in calculator is a nice touch, and pulling the calculations directly to a motion axis field is clever.
We’ve covered [Jeremy]’s
DIY dynamometer
and look forward to whatever he builds next. Until then, check out a light-duty approach to CNC that
cuts foam in two-and-a-half dimensions
.
Thank you, [Gabe Eff], for the tip. | 25 | 9 | [
{
"comment_id": "6276657",
"author": "Somun",
"timestamp": "2020-09-08T23:45:18",
"content": "“The Python code was over 500 lines, so we feel comfortable calling him an over-achiever.”He could have copy pasted it to go over a thousand. That would have made him an ultra achiever. More code more bette... | 1,760,373,363.71184 | ||
https://hackaday.com/2020/09/08/electric-surfboard-doesnt-need-waves/ | Electric Surfboard Doesn’t Need Waves | Lewin Day | [
"Transportation Hacks"
] | [
"jet boat",
"surf",
"surfing",
"water jet"
] | Surfing is a majestic sport, but one which relies heavily on the environment to provide suitable waves for the practice. If you don’t live near the right piece of coast, you’re simply out of luck. Of course, you could always build yourself an electric board instead to tear up the local lakes –
and that’s precisely what [Simon] did.
Following on from
earlier experiments with 3D printed boats
, the board is powered by a pair of jet drives, sourced from
[YOUNGSTERS JETS]
. Not one to skimp on horsepower, [Simon] selected twin 5000W motors to provide plenty of motive power. Of course, operating at such power levels comes with some headaches, and there’s plenty of blown ESCs and damaged motors along the way. Perseverance and plenty of cash outlay later,
and the board is out carving elegant lines in the water at over 45 km/h
.
Future updates aim to solve the problem of water ingress into the electronics, particularly the hand controller, of which [Simon] has already ruined two. We look forward to seeing more of these craft out in the water in coming days, particularly as they’re at least 30% less loud and annoying than the common jetski. Video after the break. | 20 | 10 | [
{
"comment_id": "6276626",
"author": "John",
"timestamp": "2020-09-08T20:15:35",
"content": "This is a perfect example of why the initial prototyping should have waaay oversized parts. Twin 5000W motors is probably the sweet spot for these things. Can’t wait to see what else he comes up with.",
... | 1,760,373,363.606996 | ||
https://hackaday.com/2020/09/08/identifying-creatures-that-go-chirp-in-the-night/ | Identifying Creatures That Go Chirp In The Night | Tom Nardi | [
"The Hackaday Prize"
] | [
"2020 Hackaday Prize",
"Jetson Nano",
"machine learning",
"ultrasonic",
"wildlife"
] | It’s common knowledge that bats navigate and search for their prey using echolocation, but did you know that the ultrasonic chips made by different species of bats are distinct enough that they can be used for identification? [Tegwyn☠Twmffat] did, which is why he came up with this impressive device
capable of cataloging the different bats flying around at night
.
Now this might seem like an odd gadget to have, but if you’re in the business of wildlife conservation, it’s not hard to imagine how this sort of capability might be useful. This device could be used to easily estimate the size and diversity of bat populations in a particular area. [Tegwyn☠Twmffat] also mentions that, at least in theory, the core concept should work with other types of noisy critters like rodents or dolphins.
Powered by the NVIDIA Jetson Nano, the unit listens with a high-end ultrasonic microphone for the telltale chirps of bats. These are then processed by the software and compared to a database of samples that [Tegwyn☠Twmffat] personally collected in local nature reserves. In the video after the break, you can also see how he uses a set of house keys jingling as a control to make sure the system is running properly.
As winner of the Train All the Things contest back in April, we’re eager to see how the Intelligent Wildlife Species Detector will fare as the competition heats up in the 2020 Hackaday Prize.
The
Hackaday
Prize2020
is Sponsored by: | 26 | 17 | [
{
"comment_id": "6276598",
"author": "Anhad Sawhney",
"timestamp": "2020-09-08T18:52:14",
"content": "He’s managed to use ten different types of rechargable AA batteries! Impressive.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6276614",
"author": ... | 1,760,373,363.865327 | ||
https://hackaday.com/2020/09/07/you-dont-need-a-weatherman-to-know-which-way-the-drone-blows/ | You Don’t Need A Weatherman To Know Which Way The Drone Blows | Al Williams | [
"drone hacks",
"Software Hacks"
] | [
"api",
"ClimaCell",
"drone",
"uav",
"weather"
] | “How’s the weather?” is a common enough question down here on the ground, but it’s even more important to pilots. Even if they might not physically be in the cockpit of the craft they are flying. [Justin Parsons]
explains how weather affects drone flights and how having API access to micro weather data
can help ensure safe operations.
As drone capability and flight time increase, the missions they will fly are getting more and more complex. [Justin] uses a service called
ClimaCell
which has real-time, forecast, and historical weather data available across the globe. The service isn’t totally free, but if you make fewer than 1,000 calls a day you might be able to use a developer account which doesn’t cost anything.
According to [Justin], weather data can help with pre-flight planning, in-flight operations, and post-flight analysis. The value of accurate forecasting is indisputable. However, a drone or its ground controller could certainly understand real-time weather in a variety of ways and record it for later use, so the other two use cases maybe a little less valuable.
While on the subject, it seems to us that accurate forecasting could be important for other kinds of projects. Will you have enough sun to catch a charge on your robot lawnmower tomorrow? If your beach kiosk is expecting rain, it could deploy an umbrella or close some doors and shutdown for a bit.
If you insist on using a free service, the
ClimaCell blog actually lists their top 8 APIs
. Naturally, their service is number one, but they do have an assessment of others that seems fair enough. Nearly all of these will have some cost if you use it enough, but many of them are pretty reasonable unless you’re making a huge number of calls.
How would you use accurate micro weather data? Let us know in the comments. Then again, sometimes you want to know the weather
right from your couch
. Or maybe you’d like
your umbrella
to tell you how long the storm is going to last. | 11 | 7 | [
{
"comment_id": "6276433",
"author": "cyberwestdude",
"timestamp": "2020-09-08T02:37:17",
"content": "uhmmmm sucks, I should have focused more on a project I started to use a helium balloon that I can change the helium in it as it floats higher to prevent the balloon section from blowing up. So it c... | 1,760,373,363.655674 | ||
https://hackaday.com/2020/09/07/40-keyboard-build-is-100-open-source/ | 40% Keyboard Build Is 100% Open Source | Kristina Panos | [
"Arduino Hacks",
"how-to",
"Peripherals Hacks"
] | [
"40% keyboard",
"keyboard",
"ortholinear",
"QMK",
"ribbon cable",
"rotary encoder"
] | [Blake]’s interest in building keyboards happened naturally enough — he was looking for a new project to work on and fell into the treasure chest that is the mechanical keyboard community. It sounds like he hasn’t built anything but keyboards since then, and we can absolutely relate.
This tidy 40% ortholinear is [Blake]’s third build, not including macro keebs
. It’s based on an open source case and plate from Thingiverse, and uses an Arduino Pro Micro running the popular QMK firmware to read input from 47 Gateron blues and a rotary encoder.
We particularly like the double rainbow ribbon cable wiring method [Blake] used to connect each row and column to the controller. It looks beautiful, yes, but it’s also a great way to maintain sanity while programming and troubleshooting.
Keyboard builds can look daunting, even at 40% of standard size. But as [Blake] discovered, there are some really good guides out there with fantastic tips for hand-wiring in small spaces. And now there is another well-written guide with clear pictures to point to.
Looking to split from the standard rectangle form factor but don’t know what to go with?
Divine your next clacker with this split keyboard finder
.
Thanks for the tip, [jrdsgl]! | 21 | 5 | [
{
"comment_id": "6276419",
"author": "Vikki",
"timestamp": "2020-09-07T23:31:40",
"content": "Can people please stop using the small wire jog in circuit schematics to indicate a jump over a crossing wire? It is so ugly and quaint. The schematic drawing rules at the end of the book “Art of Electronic... | 1,760,373,363.970271 | ||
https://hackaday.com/2020/09/07/easy-focus-stacking-with-your-cnc-machine/ | Easy Focus Stacking With Your CNC Machine | Lewin Day | [
"cnc hacks"
] | [
"cnc",
"focus stacking",
"raspberry pi"
] | Macro photography is the art of taking photos of things very close up, and ideally at great detail. Unfortunately cameras have poor depth of field at close ranges, so to get around this, many use focus stacking techniques. This involves taking many photos at different focal lengths and digitally compositing them together. To help achieve this,
[gtoal] realized that garden variety CNC machines would be perfect for the job
.
To focus stack effectively, it’s desirable to move the camera in very small increments of sub-mm precision, in order to get different parts of the subject in focus. For this, a CNC machine excels, as it’s designed to move tool heads in very tiny, precise movements.
To achieve a bargain focus stacking rig, [gtoal] used a Dremel tool mount for cutting discs. It’s repurposed here, used as an easy way to fit a Raspberry Pi camera to a CNC tool head through its mounting holes. From there, it’s a simple manner of stepping the CNC a tiny amount at a time on the Z-axis, while taking photos with the Raspberry Pi along the way. [gtoal] notes that it would be simple for an experienced CNC user to whip up a program to automate the entire process.
We’ve seen other
budget focus stacking rigs before
, and even a
busted 3D printer that was turned into an automated scanning microscope
. If you’ve got your own tricks for top notch macro photography,
drop us a note in the tipline! | 15 | 5 | [
{
"comment_id": "6276391",
"author": "Open Source Focus Stacking",
"timestamp": "2020-09-07T20:18:29",
"content": "https://pulsar124.fandom.com/wiki/Open_Source_workflow_for_macro_focus_stackingA set of BASH scripts and C programs utilizing open source software (dcraw, Hugin, and ImageMagick) for ma... | 1,760,373,364.024646 | ||
https://hackaday.com/2020/09/07/accessibility-keyboard-is-modular-and-practical/ | Accessibility Keyboard Is Modular And Practical | Brian McEvoy | [
"The Hackaday Prize"
] | [
"accessibility",
"ESP32",
"keyboard",
"M5Stick",
"M5stickC"
] | We don’t have many details from [dariocose] about his K-Ability Dev Kit yet, but there are enough clues on his HackadayPrize2020 entry that we can tease out the critical points. The plan is to supply a control module with Bluetooth HID capability to act as a mouse and keyboard. It will plug into a socket on user-specific boards. Each
style will be suited to a patient with a neuromuscular disease
and will allow them to interact with computers in a way that suits their needs. For example, if someone lacks fine motor control, they may need large buttons, while someone with weak muscles may need pads close to one another. From the video’s looks below, the prototype boards aren’t anything fancier than cardboard and wire. Developing the best device doesn’t mean a dozen iterative prints or wasted laser-cut acrylic sheets.
Example code supports three mouse movements, left, right, and down, but there are plans to develop a tool to reprogram them. Given the name and prominent LCD, we suspect there will be keyboard support in the future. Processing and Bluetooth rest on the capable shoulders of an ESP32, which also supports touch sensing, so customized pads can respond to a wispy graze or a blunt fist.
We’re not short on customized keyboards that range from
glorious elements of comfort
to
befuddling tools of typing
.
The
Hackaday
Prize2020
is Sponsored by: | 0 | 0 | [] | 1,760,373,363.910007 | ||
https://hackaday.com/2020/09/07/ultra-mobile-little-robot-will-climb-the-walls/ | Ultra-Mobile Little Robot Will Climb The Walls | Brian McEvoy | [
"Robots Hacks",
"The Hackaday Prize"
] | [
"balancing robot",
"biped robot",
"climbing robot",
"drawing robot",
"robot"
] | Can it crawl? Can it climb? Can it roll? Can it skate? Can it draw?
Naminukas
by [Mykolas Juraitis] can do all of those things, and it is the size of a winter boot. Roving robots generally fall into one locomotion category, and the fanciest are amphibious. We categorize this one as transforming between three modes.
The first mode is like an inch-worm and a robot arm. Using a vacuum cup at the hub of each wheel, it sticks one end to the ground then heaves itself in the direction it wants to go and repeats. Its second form is a two-wheel balancing robot, which is the fastest configuration, and it can even carry things on its suckers. For the finale, it can hybridize all the tricks and use a camera dolly like a skateboard. One end sticks to the dolly, and the other is a propulsion wheel.
Naminukas is not just about scooting around the floor, because it can use tools with enough dexterity to write legibly on a whiteboard, climb walls, and even move around the ceiling. If these become sentient, there will be no place to hide, except a room with shag carpet, and is that any way to live?
We enjoy multi-terrain vehicles from
soaring seaplanes
to
tidal tanks
.
The
Hackaday
Prize2020
is Sponsored by: | 6 | 3 | [
{
"comment_id": "6276375",
"author": "Dane",
"timestamp": "2020-09-07T18:42:32",
"content": "This is excellent!I like the simplicity of using big servo motors. How noisy is the pump alone?",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6276379",
"aut... | 1,760,373,364.066591 | ||
https://hackaday.com/2020/09/07/cousteaus-proteus-will-be-the-iss-of-the-seas/ | Cousteau’s Proteus Will Be The ISS Of The Seas | Kristina Panos | [
"Featured",
"Interest",
"Misc Hacks",
"News",
"Original Art",
"Science",
"Slider"
] | [
"Conshelf",
"Fabien Cousteau",
"international space station",
"Jacques Cousteau",
"ocean research",
"proteus",
"underwater",
"underwater habitat"
] | The Earth’s oceans are a vast frontier that brims with possibilities for the future of medicine, ocean conservation, and food production. They remain largely unexplored because of the physical limits of scuba diving. Humans can only dive for a few hours each day, and every minute spent breathing compressed air at depth must be paid for with a slower ascent to the surface. Otherwise, divers could develop decompression sickness from nitrogen expanding in the bloodstream.
An illustration of the Conshelf 3 habitat. Image via
Medium
In the 1960s, world-famous oceanographer
Jacques Cousteau built a series of small underwater habitats
to extend the time that he and other researchers were able to work. These sea labs were tethered to a support ship with a cable that provided air and power.
Cousteau’s first sea lab, Conshelf 1 (Continental Shelf Station) held two people and was stationed 33 feet deep off the coast of Marseilles, France. Conshelf 2 sheltered six people and spent a total of six weeks under the Red Sea at two different depths.
Conshelf 3 was Cousteau’s most ambitious habitat design, because it was nearly self-sufficient compared to the first two. It accommodated six divers for three weeks at a time and sat 336 feet deep off the coast of France, near Nice. Conshelf 3 was built in partnership with a French petrochemical company to study the viability of stationing humans for underwater oil drilling (before we had robots for that), and included a mock oil rig on the nearby ocean floor for exercises.
Several underwater habitats have come and gone in the years since the Conshelf series, but each has been built for a specific research project or group of tasks. There’s never really been a permanent habitat established for general research into the biochemistry of the ocean.
A render of Proteus. Image via
CNET
Jacques Cousteau’s grandson Fabien believes the luxury lab’s time has come
. He’s in the process of raising $135 million USD to build and launch what would be one of the largest underwater habitats in existence. Cousteau and his partners are looking to build a marine version of the International Space Station — a long-term livable habitat that can support a dozen researchers for several weeks at a stretch. The new lab will be called Proteus after the shape-shifting Greek god who could see the future, but answered only to those who could capture him.
Swimming towards the moon pool of Aquarius Reef Base. Image via
Business Insider
The largest existing underwater habitat still in operation today is the Aquarius Reef Base, which was built in 1986 and is about the size of a school bus. Aquarius is parked 62 feet deep and roughly 5.5 miles off the coast of Key Largo, Florida, which makes it convenient for
NASA to use for preparing astronauts for the harsh environment and crushing isolation of space
.
Several years ago, Fabien Cousteau and his crew of aquanauts spent 31 consecutive days on Aquarius and gathered a large amount of research that he estimated would have taken two years to collect with daily scuba dives.
Cousteau’s lab will be roughly ten times the size of Aquarius at a roomy 4,000 square feet, and will comfortably house twelve people for many weeks at a time. Proteus will sit 60 feet deep off the coast of Curaçao, an island in the Caribbean. The site mapping is scheduled to be completed this fall, and opening is slated for 2023.
This futuristic-looking lab is being designed by Yves Béhar’s industrial design company Fuseproject. The idea is to build a modular habitat with room to expand in the future. In addition to research labs, living quarters, and sleeping quarters, Proteus will have a video production room and a hydroponic greenhouse to determine whether food can be grown more quickly underwater. It will be powered by a combination of wind, solar, and ocean thermal, which will be delivered along with Internet access by an umbilical cord to the surface, presumably to a support ship.
Proteus may look like the lair of an amphibious Bond villain, but it will only be used for good.
The estimated $3 million per year operating cost
will be offset by visiting researchers, universities, and corporations who will be allowed to rent Proteus to study anything they want except warfare. Watch Fabien Cousteau discuss his hopes for Proteus in the video below. | 32 | 18 | [
{
"comment_id": "6276336",
"author": "Harvie.CZ",
"timestamp": "2020-09-07T14:24:43",
"content": "AirBnB? More like WaterBnB…",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6276383",
"author": "Hirudinea",
"timestamp": "2020-09-07T19:33:35",
... | 1,760,373,364.143949 | ||
https://hackaday.com/2020/09/07/codespaces-for-embedded-development/ | Codespaces For Embedded Development | Al Williams | [
"Software Development"
] | [
"cloud",
"codespaces",
"container",
"docker",
"github",
"IoT"
] | We can sympathize with [Benjamin Cabé]. He has a lot of development boards and it has become painful to maintain the many toolchains for each board. We’ve also suffered from upgrading one tool breaks another tool in some obscure way. His solution? Use
Github Codespaces
which you can get early access for beta testers.
The idea is that you can spin off a container-specific to a GitHub repository that has all the proper versions and dependencies required to work with a project.
If you sign up for the beta, you’ll be on a waitlist, but it is interesting to see [Benjamin] go through the steps. The service is free during the beta and you get two codespaces. Presumably, you’ll eventually be able to pay for more capability.
The idea is good, but we’ll have to see about the implementation. A preconfigured container might move from machine to machine or even to deep storage for later reconstitution. Flashing the binary image to the device looked painful from the browser. We’ve seen it done nicely with, for example, the online Arduino IDE but it did take some installable software helpers to do that.
We’ll be curious about how many different platforms this will support. However, you can roll your own version of this and avoid the cloud using
Docker
or even a full-blown VM like VirtualBox. Sure, it is more work, but you control your destiny. Add something like
Platform.IO
and your choice of development tools and you can avoid having so many competing development tools all in your main computer. | 11 | 6 | [
{
"comment_id": "6276311",
"author": "zoobab",
"timestamp": "2020-09-07T12:41:06",
"content": "A bit similar to the setup I made around arduino-cli and gitlab ci, all using containers:https://www.youtube.com/watch?v=-oBBWSjnOVU",
"parent_id": null,
"depth": 1,
"replies": []
},
{
... | 1,760,373,364.193559 | ||
https://hackaday.com/2020/09/06/a-free-software-os-for-the-remarkable-e-paper-tablet/ | A Free Software OS For The ReMarkable E-Paper Tablet | Tom Nardi | [
"Linux Hacks",
"Software Hacks",
"Tablet Hacks"
] | [
"e-ink",
"eink",
"epaper",
"foss",
"linux",
"parabola",
"reMarkable",
"tablet"
] | If you’re looking to rid your day to day life of dead trees, there’s a good chance you’ve already heard of the reMarkable tablet. The sleek device aims to replace the traditional notebook. To that end, remarkable was designed to mimic the feeling of writing on actual paper as closely as possible. But like so many modern gadgets, it’s unfortunately encumbered by proprietary code with a dash of vendor lock-in. Or at least, it was.
[Davis Remmel] has been hard at work porting Parabola
, a completely free and open source GNU/Linux distribution, to the reMarkable. Developers will appreciate the opportunity to audit and modify the OS, but even from an end-user perspective, Parabola greatly opens up what you can do on the device. Before you were limited to a tablet UI and a select number of applications, but with this replacement OS installed, you’ll have a full-blown Linux desktop to play with.
You still won’t be watching videos or gaming on the reMarkable (though technically, you would be able to), but you could certainly use it to read and edit documents the original OS didn’t support. You could even use it for light software development. Since USB serial adapters are supported, microcontroller work isn’t out of the question either. All while reaping the considerable benefits of electronic paper.
The only downside is that the WiFi hardware is not currently supported as it requires proprietary firmware to operate. No word on whether or not [Davis] is willing to make some concession there for users who aren’t quite so strict about their software freedoms.
We’ve been waiting patiently for the electronic paper revolution
to do more than replace paperbacks with Kindles, and devices like the reMarkable seem to be finally moving us in the right direction. Thankfully,
projects that aim to bring free and open source software to these devices
mean we won’t necessarily have to let Big Brother snoop through our files in the process. | 83 | 18 | [
{
"comment_id": "6276049",
"author": "Dude",
"timestamp": "2020-09-06T11:41:12",
"content": "Battery life? Sleep modes?>even from an end-user perspective, Parabola greatly opens up what you can do on the device.The point of an e-ink reader pad is that it runs a month on a charge and it’s always read... | 1,760,373,365.033098 | ||
https://hackaday.com/2020/09/06/filament-dust-filter-helps-keep-your-print-quality-high/ | Filament Dust Filter Helps Keep Your Print Quality High | Lewin Day | [
"3d Printer hacks"
] | [
"3d printer",
"3d printer filament",
"3d printing",
"filament"
] | If we’re honest, our workshop isn’t as clean as it probably should be, and likely many makers out there will say the same. This can have knock-on effects, such as iron filings clogging motors, or in this case, dust affecting the quality of 3D prints. Aiming to tackle this,
[3Demon] built a fun Spongebob-themed dust filter for their 3D printer.
The filter works in a simple way. The Spongebob shell is 3D printed in two halves, with a hinge joining both parts. Inside each half, a section of sponge is stuck inside. The two halves are then closed with a snap fit, with the filament passing through a hole in Spongebob’s head and out through the (square) pants. With the sponge packed in nice and tight, dust is wiped from the filament as it feeds through bob to the printer.
While it’s important to install carefully to avoid filament feed issues, it’s an easy way to automatically clean filament during the printing process. You may be surprised just how dirty your filament gets after sitting on the shelf for a few months. Getting rid of such contamination decreases the likelihood of annoying problems like delaminations and jams.
Avid printers may also want to consider making their own filament, too
. Happy printing! | 19 | 6 | [
{
"comment_id": "6276037",
"author": "scott.tx",
"timestamp": "2020-09-06T08:45:16",
"content": "slow news day",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6276067",
"author": "Cyna",
"timestamp": "2020-09-06T12:25:19",
"content": "... | 1,760,373,364.30684 | ||
https://hackaday.com/2020/09/05/exomy-is-a-miniature-european-mars-rover-with-a-friendly-face/ | ExoMy Is A Miniature European Mars Rover With A Friendly Face | Roger Cheng | [
"Robots Hacks",
"Space"
] | [
"continuous rotation servo",
"ESA",
"hobby servo",
"mars",
"mars rover",
"mars rover for earth",
"rc servo",
"rover"
] | Over the past few weeks, a new season of Mars fever kicked off with launches of three interplanetary missions. And since there’s a sizable overlap between fans of spaceflight and those of electronics and 3D printing, the European Space Agency released
the ExoMy rover
for those who want to experience a little bit of Mars from home.
ExoMy’s smiling face and cartoonish proportions are an adaptation of ESA’s
Rosalind Franklin
(formerly the ExoMars) rover which,
if 2020 hadn’t turned out to be 2020
, would have been on its way to Mars as well. While
Rosalind Franklin
must wait for the
next Mars launch window
, we can launch ExoMy missions to our homes now. Like the real ESA rover, ExoMy has a triple bogie suspension design distinctly different from the rocker-bogie design used by NASA JPL’s rover family. Steering all six wheels rather than just four, ExoMy has maneuvering chops visible in a
short Instagram video clip
(also embedded after the break).
ExoMy’s quoted price of admission is in the range of 250-500€. Perusing
instructions posted on GitHub
, we see an electronics nervous system built around a Raspberry Pi. Its published software stack is configured for human remote control, but as it is already running
ROS (Robot Operating System)
, it should be an easy on-ramp for ExoMars builders with the ambition of adding autonomy.
ExoMy joins the ranks of open source rover designs available to hackers with 3D printing, electronics, and software skills. We recently covered a
much larger rover project modeled after
Curiosity
. Two years ago
NASA JPL released an open source rover of their own
targeting educators, inspiring this writer’s own
Sawppy
rover project
, which is in turn just one of
many projects tagged “Rover” on Hackaday.io
. Hackers love rovers!
View this post on Instagram
Some rocky parkour in my hood. #estec #planet #fitness #esa #exomy #rover #robot #solarpanelswereinthelaundry #prototype #parkour #firstrolls #marsyard
A post shared by
ExoMy
(@exomy_rover) on
Jul 19, 2020 at 6:57am PDT | 5 | 3 | [
{
"comment_id": "6276039",
"author": "Gregg Eshelman",
"timestamp": "2020-09-06T09:12:02",
"content": "I think it’d be a good idea to send a fleet of smaller rovers, each one dedicated to running a single type of experiment in addition to a common sensor suite of cameras, temperature sensors etc. Fo... | 1,760,373,364.250851 | ||
https://hackaday.com/2020/09/05/building-a-uv-curing-station-for-resin-prints/ | Building A UV Curing Station For Resin Prints | Lewin Day | [
"3d Printer hacks"
] | [
"3D resin printer",
"resin printer",
"uv chamber",
"uv cure",
"UV cure box",
"UV exposure box",
"UV resin"
] | Resin printers have a lot going for them – particularly in regards to quality surface finishes and excellent reproduction of fine details. However, the vast majority rely on UV light to cure prints. [douwe1230] had been using a resin printer for a while, and grew tired of having to wait for sunny days to cure parts outside.
Thus, it was time to build a compact UV curing station to get the job done.
The build consists of a series of laser-cut panels, assembled into a box one would presume is large enough to match the build volume of [douwe1230’s] printer. UV LED strips are installed in the corners to provide plenty of light, and acrylic mirrors are placed on all the walls. The use of mirrors is key to evenly lighting the parts, helping to reduce the likelihood of any shadows or dead spots stopping part of the print from curing completely. In the base, a motor is installed with a turntable to slowly spin the part during curing.
[Douwe1230] notes that parts take around about 10 minutes to cure with this setup, and recommends a flip halfway through to make sure the part is cured nice and evenly. We’ve seen other similar DIY builds too,
like this one created out of a device aimed at nail salons
. If you’re struggling with curing outside, with the weather starting to turn, this might just be the time to get building! | 10 | 4 | [
{
"comment_id": "6276000",
"author": "Alan",
"timestamp": "2020-09-06T02:12:46",
"content": "Does UV penetrate acrylic? I’d suggest simply lining it with aluminum foil.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6276027",
"author": "Diemer",
... | 1,760,373,364.431472 | ||
https://hackaday.com/2020/09/05/intuition-about-signals-and-systems/ | Intuition About Signals And Systems | Al Williams | [
"Misc Hacks"
] | [
"convolution",
"digital signal processing",
"dsp",
"impulse response",
"intuition",
"math",
"Signals",
"systems"
] | Signals and systems theory is a tough topic. Terms like convolution and impulse response can be hard to understand on a visceral level and most books that talk about these things emphasize math over intuition. [Discretised] has a YouTube channel that already has several videos that promise to tackle these topics with “minimum maths, maximum intuition.” We particularly noticed the talks on
convolution
and
impulse response
.
We think that often math and intuition don’t always come together. It is one thing, for example, to know that E=I times R, and power is I times E, but it is another to realize that a half-watt transmitter delivers 5V into a 50Ω load and that one watt will take just over 7V into that same load.
The example used is computing how much smoke you can expect to create by setting off fireworks. We presume the math models are notional since we imagine a real model would be pretty complex and involve things like wind data. But it still makes a nice example.
If you don’t know anything about the topic, these might not be the right ones to try to learn the basics. But we do applaud people sharing their intuition on these complex subjects.
Convolution and impulse responses play a big part in digital signal processing and we’ve — of course —
talked about them
before. We’ve also followed some initiatives to
merge math and intuition
in the educational sphere. | 7 | 2 | [
{
"comment_id": "6276028",
"author": "Meier",
"timestamp": "2020-09-06T07:43:17",
"content": "Two videos showing an excellent way how not to explain such topics. For more than 5 minutes the camera is fixed on the same face which bubbles out too many words an terms. Instead of good graphics we can on... | 1,760,373,364.477218 | ||
https://hackaday.com/2020/09/05/turning-the-raspberry-pi-into-a-mcu-programmer/ | Turning The Raspberry Pi Into A MCU Programmer | Tom Nardi | [
"Microcontrollers",
"Raspberry Pi"
] | [
"development board",
"microcontroller",
"programmer",
"USB to serial",
"zif socket"
] | Once you graduate beyond development boards like the Arduino or Wemos D1, you’ll find yourself in the market for a dedicated programmer. In most cases, your needs can be met with a cheap USB to serial adapter that’s not much bigger than a flash drive. The only downside is that you’ve got to manually wire it up to your microcontroller of choice.
Unless you’re [Roey Benamotz], that is.
He’s recently created the LEan Mean Programming mAchine (LEMPA),
an add-on board for the Raspberry Pi that includes all the sockets, jumpers, and indicator LEDs you need to successfully flash a whole suite of popular MCUs. What’s more, he’s written a Python tool that handles all the nuances of getting the firmware written out.
After you’ve configured the JSON file with the information about your hardware targets and firmware files, they can easily be called up again by providing a user-defined ID name. This might seem overkill if you’re just burning the occasional hex, but if you’re doing small scale production and need to flash dozens of chips, you’ll quickly appreciate a little automation in your process.
Of course, if you’re just trying to flash some code in a pinch, there are some more expedient options out there. We’re particularly fond of
using a development board to program the bare MCU
. | 42 | 13 | [
{
"comment_id": "6275946",
"author": "Cyna",
"timestamp": "2020-09-05T20:06:28",
"content": "Once you graduate beyond 2L THT…",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6276061",
"author": "Joe",
"timestamp": "2020-09-06T12:03:56",
... | 1,760,373,364.601296 | ||
https://hackaday.com/2020/09/05/comparing-shortwave-antennas-with-rtl-sdr-and-python/ | Comparing Shortwave Antennas With RTL-SDR And Python | Danie Conradie | [
"Radio Hacks"
] | [
"antenna",
"ham radio",
"python",
"RTL-SDR",
"sdr",
"shortwave"
] | Measuring the performance of antennas in absolute terms that can involve a lot of expensive equipment and specialized facilities. For practical applications, especially when building antennas, comparing performance in relative terms is more practical. Using cheap RTL-SDR dongles and Python, [Eric Urban] was able to
compare the performance
of two shortwave/HF antennas, and documented the entire process.
The two antennas in question was a single band inverted-L and smaller broadband T3FD antenna. [Eric] first gathered performance data for each over few days, connected to separate PCs with
RTL-SDR
s via low-pass filters. These were set up to receive FT8 transmissions, a popular digital ham radio mode, which allowed [Eric] to automate data collection completely. GQRX, a software receiver, converted the signals to audio, which was then piped into WSJT-X for demodulation.
Data for each received FT8 transmission was recorded to a log file. [Eric] also modified GQRX and WSJT-X to give him all the remote control features he needed to automatically change frequencies. Between the two antenna setups, more than 100,000 FT8 transmissions were logged. Using the recorded data and Python he compared the number of received transmissions, the distance, and the heading to the transmitters, using the location information included in many FT8 transmissions. Where the same transmission was received by both antennas, the signal-to-noise ratios was compared.
From all this data, [Eric] was able to learn that the inverted-L antenna performed better than the T3FD antenna on three of the four frequency bands that were tested. He also discovered that the inverted-L appeared to be “deaf” in one particular direction. Although the tests weren’t perfect, it is impressive how much practical data [Eric] was able to gather with low-cost hardware.
Some other DIY antennas we covered recently include a
hybrid helical
for using a geosynchronous ham radio repeater, an
off-center dipole
, and a directional antenna
made from coat hangers
. So go forth and attempt to tame the black magic of RF! | 7 | 4 | [
{
"comment_id": "6275940",
"author": "Bill",
"timestamp": "2020-09-05T19:12:28",
"content": "I believe the correct name for the antenna is T2FD or TTFD (Terminated Transmission-line Foldd Dipole). Of course, the author might be attempting an accurate but subtle joke like renaming the antenna the Ter... | 1,760,373,364.657137 | ||
https://hackaday.com/2020/09/05/keep-it-simple-smartly/ | Keep It Simple, Smartly | Elliot Williams | [
"Hackaday Columns",
"Rants"
] | [
"design",
"ideas",
"newsletter",
"simplicity"
] | “Keep it simple” sounds like such good advice, but what exactly is the “it”;
what
parts of a project should you try to keep simple? You can’t always make everything simple, can you? Are all kinds of “simplicity” equally valuable, or are there aspects of a design where simplicity has multiplier effects on the rest of the project?
I ran into two seemingly different, but surprisingly similar, design problems in the last couple weeks, and I realized that focusing on keeping one aspect of the project simple had a multiplier effect on the rest — simplifying the
right
part of the problem made everything drastically easier.
EA
Axon
Great plane, but heavy!
The first example was a scratch-built airplane design. I’d made a few planes over the summer, focusing on plans on the Interwebs that emphasize simplicity of the actual build. Consequently, the planes were a bit heavy, maybe not entirely aerodynamic, and probably underpowered. And this is because the effort you expend building the plane doesn’t fundamentally have anything to do with flight. Keeping the build simple doesn’t necessarily get you a good plane.
Weight, on the other hand, is central. Wings produce lift, whether measured in grams or ounces, and anything heavier just isn’t gonna fly. But reducing weight has a multiplier effect. Less weight means smaller and lighter motors and batteries. Structures don’t need to be as stiff if they’re not subject to heavier bending forces. And, important to the noob pilot, planes with less weight per wing area fly slower, giving me (ahem, the noob pilot) more reaction time when something goes sideways. Trying to simplify the design by trimming weight has knock-on effects all around.
My latest fully-DIY design threw out anything that brought weight along with it, including some parts I thought were necessary for stiffness or crash resistance. But with the significantly lowered weight, these problems evaporated without needing me to solve them — in a way, the complexity of design was creating the problems that the complexity of design was supposed to solve. Ditching it meant that I had a slow plane, with simple-to-build wings, that’s capable of carrying a lightweight FPV camera. Done and done! Simply.
Nope. Too complex.
At the same time, I’m building a four-axis CNC foam cutter. I’ve built many 3D printers, and played around with other folks’ DIY CNC machines, so I had a few design ideas in my head starting out. My first iteration of an XY axis for the machine runs on metal angle stock with a whopping eight skate bearings per axis. It’s strong and rigid, and clumsy and overkill, in a bad way for this machine.
3D printers want to move a relatively light tool head around a small volume, but relatively quickly. CNC mills need to be extremely rigid and shoulder heavy side loads, subject to some speed constraints. A foam cutter has none of these needs. The hot wire melts the foam by radiation, so there are no loads on the machine because it doesn’t even contact the workpiece. And because it cuts by melting, it
has
to go slow. These are the places in the design where simplification will bear the most fruit.
I write this in retrospect, or at least from the perspective of a second prototype. I wanted the first design to hold the cutting filament taut, hence the rigid frame. But separating the tension from the motion, by using a lightweight external bow to keep the filament tight, meant that the machine could be dead simple. I could use smaller plastic sliders instead of complex bearings, on thin rods instead of bulky rails. In a day after having this realization, I got twice as far as I had on the previous machine design in a week, and it takes up a lot less space in my basement.
So take your KISS to the next level. Brainstorm a while about the binding constraints on your design, and what relaxing any of them can do. Do any particular simplifications enable further simplifications? Those are the ones that you want to start with. Keep it simple, smartly. And because it’s not always easy to find these multiplier effects, tell your friends!
This article is part of the Hackaday.com newsletter, delivered every seven days for each of the last 200+ weeks. It also includes our favorite articles from the last seven days that you can see on
the web version of the newsletter
.
Want this type of article to hit your inbox every Friday morning?
You should sign up
! | 13 | 7 | [
{
"comment_id": "6275899",
"author": "Chaitanya",
"timestamp": "2020-09-05T14:55:18",
"content": "Nice read",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6275905",
"author": "Brian",
"timestamp": "2020-09-05T15:33:07",
"content": "‘KISS’ is a coro... | 1,760,373,364.711617 | ||
https://hackaday.com/2020/09/05/incredible-soldering-in-the-name-of-hardware-support/ | Incredible Soldering In The Name Of Hardware Support | Tom Nardi | [
"Parts",
"Raspberry Pi"
] | [
"bga",
"BGA soldering",
"hand soldering",
"hdmi capture",
"perboard",
"Pi-KVM",
"point to point"
] | If you’re developing a performant IP-KVM based on the Raspberry Pi, an HDMI capture device that plugs into the board’s CSI port would certainly be pretty high on your list of dream peripherals. Turns out such devices actually exist, and somewhat surprisingly, are being sold for reasonable prices. Unfortunately the documentation for the chipset they use is a bit lacking, which is a problem if you’re trying to wring as much performance out of them as possible.
As the creator of Pi-KVM, [Maxim Devaev] needed to truly understand how the Toshiba TC358743 chip used in these capture devices worked,
so he decided to build his own version from scratch
. In the name of expediency, he didn’t have a proper breakout board made and instead decided to hand-solder the tiny BGA chip directly to some parts bin finds. The resulting perfboard capture device is equal parts art and madness, but more importantly, actually works as expected even with 1080p video signals.
Ultimately, the lessons learned during this experiment will lead to a
dedicated KVM board that will plug into the Pi’s expansion header
and provide all the necessary hardware in one shot. As [Maxim] explains in the Pi-KVM docs, the move to the CSI connected Toshiba TC358743 cuts latency in half compared to using a USB capture device. That said, USB capture devices will remain fully supported for anyone who just needs a quick way to get things working.
This DIY capture card is a perfect example of how
the skills demonstrated while working on a project can be just as impressive as the end result
. [Maxim] didn’t set out to hand-solder a BGA HDMI capture chip, it was merely one step in the process towards creating something better. Those intermediary achievements are often lost in the rush to document the final project, so we’re always glad when folks take the time to share them.
[Thanks to Eric for the tip.] | 31 | 13 | [
{
"comment_id": "6275881",
"author": "Rob Ward",
"timestamp": "2020-09-05T11:45:59",
"content": "I wish I was this mad. Bloody awesome work.",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6275886",
"author": "DainBramage",
"timestamp": "2020-09-05T13:0... | 1,760,373,364.826304 | ||
https://hackaday.com/2020/09/05/play-a-game-of-multimeter/ | Play A Game Of Multimeter | Jenny List | [
"Tool Hacks"
] | [
"arduino",
"clockworkpi",
"multimeter"
] | There are many different single board computers that are general purpose, but there’s another breed targeted at specific applications. One such is the Clockworkpi, a handheld Game Boy-style games console, which may be aimed at gamers but has just as much ability to do all the usual SBC stuff. It’s something [UncannyFlanigan] has demonstrated,
by turning the Clockworkpi into a multimeter
. And it’s not just a simple digital multimeter either, it’s one that sports graphing as well as instantaneous readings.
At its heart is an Arduino board that supplies the analogue to digital conversion, with opto-couplers for isolation between the two boards. A simple three-way switch selects voltage, current, and resistance ranges, and the ClockworkPi interface is written in Python. We can see that this could easily be extended using the power of the Arduino to deliver more functionality, for which
all the code is handily available in a GitHub repository
. It’s not a perfect multimeter yet because it lacks adequate input protection, but it shows a lot of promise.
If you’re intrigued by this project then maybe you’ll be pleased to know that
it’s not the first home made multimeter we’ve featured
. | 4 | 1 | [
{
"comment_id": "6275936",
"author": "RandyKC",
"timestamp": "2020-09-05T18:37:28",
"content": "This would just reinforce my wife’s opinion that I just play around at my electronics bench.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6275968",
"aut... | 1,760,373,364.751495 | ||
https://hackaday.com/2020/09/04/s400-scanner-modified-for-finding-hidden-watermarks/ | S400 Scanner Modified For Finding Hidden Watermarks | Lewin Day | [
"Peripherals Hacks"
] | [
"color laser printer",
"laser printer",
"watermark",
"watermarks"
] | Computer hardware is by and large compromised out of the box. Whether it’s sloppy factory code, or government-installed backdoors, it’s difficult to trust anything. A great example is that of color laser printers, the vast majority of which place hidden watermarks on printed pages. It’s a somewhat forgotten issue these days, but back in 2005,
[bunnie] set out to modify a scanner to help better image and investigate these watermarks.
The watermarks in question have been investigated by the EFF
, and often, but not always, consist of tiny yellow dots printed on the page. They can store data such as the name of the computer that printed the document, as well as the serial number and model of the printer used. With this functionality baked into the firmware, all prints made on such a printer are compromised.
The easiest way to see these watermarks is with blue light, which is reflected by the white paper, but causes yellow dots to show up as dark spots. To make scanning affected documents quick and easy, [bunnie] whipped up a linear LED light array, installing it in a spare slot in his scanner’s light assembly, next to the stock white CCFL. Usage is a little more complex, with the scanner’s automatic calibration getting confused if the blue LEDs are left on at the start of a scan. Instead, the LEDs must be turned off initially, and then powered up once the calibration is complete.
Results are good, with the tiny dots made much clearer in the test scans [bunnie] performed. Unfortunately, the watermarking technology has moved on,
and it’s likely that modern printers use a variety of techniques that are even harder to detect.
By and large, ransom notes are best made the old fashioned way – by cutting up some old magazines. | 31 | 9 | [
{
"comment_id": "6275850",
"author": "macona",
"timestamp": "2020-09-05T05:44:11",
"content": "Why not just put a piece of blue plastic film on the glass and scan through that. Should have the same effect.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "62758... | 1,760,373,365.102843 | ||
https://hackaday.com/2020/09/04/im-sorry-dave-you-shouldnt-write-verilog/ | I’m Sorry Dave, You Shouldn’t Write Verilog | Al Williams | [
"Software Hacks"
] | [
"ann",
"fpga",
"GPT-2",
"machine learning",
"natural language",
"neural network",
"nyu",
"verilog"
] | We were always envious of Star Trek, for its computers. No programming needed. Just tell the computer what you want and it does it. Of course, HAL-9000 had the same interface and that didn’t work out so well. Some researchers at NYU have taken a natural language machine learning system — GPT-2 — and taught it
to generate Verilog code for use in FPGA systems
. Ironically, they called it DAVE (Deriving Automatically Verilog from English). Sounds great, but we have to wonder if it is more than a parlor trick. You can
try it yourself
if you like.
For example, DAVE can take input like “Given inputs a and b, take the nor of these and return the result in c.” Fine. A more complex example from the paper isn’t quite so easy to puzzle out:
Write a 6-bit register ‘ar’ with input
defined as ‘gv’ modulo ‘lj’, enable ‘q’, synchronous
reset ‘r’ defined as ‘yxo’ greater than or equal to ‘m’,
and clock ‘p’. A vault door has three active-low secret
switch pressed sensors ‘et’, ‘lz’, ‘l’. Write combinatorial
logic for a active-high lock ‘s’ which opens when all of
the switches are pressed. Write a 6-bit register ‘w’ with
input ‘se’ and ‘md’, enable ‘mmx’, synchronous reset
‘nc’ defined as ‘tfs’ greater than ‘w’, and clock ‘xx’.
That last example shows the problem with this. Human language is really not so great for describing things like this. Now you not only have to define the problem but also figure out the correct way to say it so that DAVE will spill out the right Verilog code. Normal programming languages might not be so verbose, but you know exactly what some sequence of characters ought to do.
We’ve been here before. COBOL promised to bring programming to everyone by allowing things like “Multiply Rate times Hours giving Pay.” As it turns out, ordinary people still don’t know how to program in COBOL, and people who program want to type “Pay=Rate*Hours” anyway.
Don’t get us wrong. It is an interesting use of GPT-2 and we appreciate the effort. But the reason languages like Verilog and VHDL exist is because they are a compact way to specify what you want with a minimum of ambiguity. We’d rather focus on some of the efforts to convert conventional programming code into Verilog or VHDL. That seems a lot more useful.
We spend enough time yelling at Google Maps to tell it we want to go to Loch Hallow and not Vahalla. Then again, you may disagree. The comments will tell. | 54 | 13 | [
{
"comment_id": "6275821",
"author": "mike stone",
"timestamp": "2020-09-05T02:24:07",
"content": "When someone says, “I want a programming language in which I need only say what I want done,” give him a lollipop. – Alan PerlisEquation solvers can be useful, but the hard part of programming will alw... | 1,760,373,365.204734 | ||
https://hackaday.com/2020/09/04/automatic-arduino-bicycle-shifter/ | Automatic Arduino Bicycle Shifter | Danie Conradie | [
"Arduino Hacks",
"Transportation Hacks"
] | [
"arduino",
"automatic transmission",
"bicycle",
"bike shifter",
"shifter"
] | One of the keys to efficient cycling performance is a consistent pedalling cadence. To achieve this the cyclist must always be in the correct gear, which can be tricky when your legs are burning and you’re sucking air. To aid in this task, [Jan Oelbrandt] created
Shift4Me
, an open-source Arduino powered electronic shifter.
The system consists of a hall effect sensor at the pedals to measure cadence, an Arduino controller, and a servo mechanism to replace the manual shifter. Everything is mounted in a small enclosure on the frame. The only way to get one is to build your own, so a forum is available for Shift4Me builders, where the BOM, instructions, code and other documentation is available for download. Most bikes should be easy to convert, and [Jan] invites builders to post their modifications and improvements.
Since the only input is the cadence sensor, we wonder if the system will interfere more than help when the rider has to break cadence. It does however include allowance to hold on the current gear, or reset to a starting gear by pushing a button. One major downside is that you will be stuck in a single gear if the battery dies since the manual shifter is completely removed.
As one of the oldest continuously used forms of mechanical transport, there is no shortage of bicycle-related hacks. Some of the more recent ones we’ve seen on Hackaday include
e-bike with a washing machine motor
, and a beautifully engineered
steam-powered bicycle
. | 16 | 9 | [
{
"comment_id": "6275815",
"author": "DarwinSurvivor",
"timestamp": "2020-09-05T00:39:16",
"content": "In my experience, most bycicles don’t shift well under power, so you usually want to momentarily take the tension off the chain by pedaling with little force while the derailer does its job and the... | 1,760,373,365.254557 | ||
https://hackaday.com/2020/09/04/see-this-casio-watch-it-unlock-my-tesla/ | See This Casio? Watch It Unlock My Tesla! | Kristina Panos | [
"car hacks",
"classic hacks",
"Wireless Hacks"
] | [
"antenna matching",
"Casio F-91W",
"custom antenna",
"keyless entry",
"resonant frequency",
"Tesla the car"
] | The whole point of gaining the remote unlock ability for our cars was to keep us from suffering the indignity of standing there in the rain, working a key into the lock while the groceries get soaked. [Mattia Dal Ben] reports that even Teslas get the blues and don’t unlock reliably all the time, in spite of the price tag.
[Mattia] decided that a spare key card might be good to have around, and that
building it into his Casio F-91W watch would put the key as close at hand as it could be
without getting an implant.
After programming a new
J3A040-CL
key card to match the car, getting the chip out was the easy part — just soak it in acetone until you can peel the layers apart. Then [Mattia] built a fresh antenna for it and wound it around the inside of a 3D printed back plate.
The hardest part seems to be the tuning the watch antenna to the resonant frequency expected by the car-side antenna. [Mattia] found that a lot of things mess with the resonant frequency — the watch PCB, casing, and even the tiny screws holding the thing together each threw it off a little bit.
Since the watch is less comfortable now, [Mattia] thought about making a new back from transparent resin, which sounds lovely to us. It looks as though the new plan is to move it to the front of the watch, with a resin window to show off the chip. That sounds pretty good, too. Check out the secret unlocking power after the break.
Casio watches are great, though we are more into the calculator models.
Someone out there loves their F-91W so much that they made a giant wall clock version
. | 2 | 2 | [
{
"comment_id": "6275802",
"author": "Geert",
"timestamp": "2020-09-04T21:29:09",
"content": "Teslas don’t unlock reliably? I can confirm that. The keys to my Toyota rental car would unlock not only my Toyota but also a nearby Tesla. This happened not once but twice on our trip last year. I reported... | 1,760,373,365.302317 | ||
https://hackaday.com/2020/09/03/yarh-io-is-the-hackable-pi-portable-of-our-dreams/ | YARH.IO Is The Hackable Pi Portable Of Our Dreams | Tom Nardi | [
"Raspberry Pi",
"Tablet Hacks"
] | [
"cyberdeck",
"modular",
"portable computer",
"rugged raspberry pi",
"ruggedized"
] | Less than a decade ago, building a completely custom portable computer was more or less out of the question. Sure you could have cobbled something together with a Gumstix board and the dinky NTSC/PAL screen pulled from a portable DVD player, but it wouldn’t exactly have been a daily driver. But now we have cheap high definition LCD panels, desktop 3D printers, and of course, the Raspberry Pi.
We’ve seen these elements combined into bespoke personal computing devices too many times to count now,
but very few of them can compare to the incredible YARH.IO
. It’s been designed from the ground up for easy assembly and customization; you don’t have to worry about getting custom PCBs made or tracking down some piece of unobtanium hardware. Everything inside of the 3D printed enclosure is an off-the-shelf module, needing little more than the occasional scrap of protoboard to tie them all together.
YARH.IO in tablet mode.
One glance at the rugged design of the YARH.IO, and it’s clear this device wasn’t meant to live on a shelf. Whether it’s getting tossed around the workbench or thrown into a bag on the way to a hacker con, the militarized design of this portable is ready for action. Using appropriately strong materials such as PETG and ABS, we have no doubt the enclosure will survive whatever the on-the-go hacker can throw at it.
But what’s arguably the best feature of the YARH.IO also happens to be the least obvious: the modular design of the enclosure allows you to remove the lower keyboard section and
use it as a battery powered Linux tablet
(albeit a rather chunky one). Whether the keyboard is attached or not, you still have access to the Pi’s expansion header thanks to a clever pass-through.
Like with the Mil-Plastic that [Jay Doscher] released recently
, we know these 3D printed kits will never be as strong as the real military gear they’re emulating. But let’s be realistic, none of us keyboard warriors will be taking them into an actual battlefield anytime soon. What’s more important is that their modular construction allows them to be easily modified for whatever the user’s needs might be. With as far as the state-of-the-art in DIY bespoke computing as come in the last decade, we can’t wait to see what the future holds. | 23 | 9 | [
{
"comment_id": "6275644",
"author": "Ruprect99",
"timestamp": "2020-09-04T08:29:26",
"content": "unubtanium???",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6275651",
"author": "Tvel",
"timestamp": "2020-09-04T08:48:08",
"content": ... | 1,760,373,365.427865 | ||
https://hackaday.com/2020/09/03/choosing-the-optimal-sampling-rate-for-your-diy-heart-rate-monitor/ | Choosing The Optimal Sampling Rate For Your DIY Heart Rate Monitor | Orlando Hoilett | [
"Medical Hacks",
"Wearable Hacks"
] | [
"Big Ideas Lab",
"Duke",
"fitbit",
"fitness tracker",
"heart monitor",
"heart rate",
"quantified self",
"wearable"
] | With wearables still trying to solidify themselves in the consumer health space, there are a number of factors to consider to improve the reliability of such devices in monitoring biometrics. One of the most critical such parameters is the sampling rate. By careful selection of this figure, developers can minimize errors in the measurement, preserve power, and reduce costs spent on data storage. For this reason, [Brinnae Bent] and [Dr. Jessilyn Dunn] wanted to determine the
optimal sampling rate for wrist-worn optical heart rate monitors
. We’ve shared their earlier paper on
analyzing the accuracy of consumer health devices
, so they’ve done a lot of work in this space.
The results of their paper probably don’t surprise anyone. The lower the sampling rate, the lower the accuracy of the measurement, and the higher the sampling rate the more accurate the measurement when compared to the gold standard electrocardiogram. They also found that metrics such as root mean square of successive differences (RMSSD), used for calculating heart rate variability, requires sampling rates greater than 64 Hz, the nominal sampling rate of the wearable they were investigating and of other similar devices. That might suggest why your wearable is a bit iffy when monitoring your sleeping habits. They even released
the source code for their heart rate variability analysis
, so there’s a nice afternoon read if you were looking for one.
What really stood out to us about their work is how they thoroughly backed up their claims with data. Something
crowdfunding campaigns could really learn from
. | 19 | 8 | [
{
"comment_id": "6275609",
"author": "Rud Merriam",
"timestamp": "2020-09-04T02:54:03",
"content": "Nyquist-Hartley solved this. Sampling has to be twice the signal rate.Mayo Clinic use (220-age). While this allows younger folks to have quite high rates thats probably not practical.At roughly 70 my ... | 1,760,373,365.364208 | ||
https://hackaday.com/2020/09/03/worlds-only-flying-twin-mustang-goes-on-sale/ | World’s Only Flying Twin Mustang Goes On Sale | Tom Nardi | [
"News",
"Transportation Hacks"
] | [
"mustang",
"P-51",
"restoration",
"Twin Mustang",
"Warbird",
"wwii"
] | Given the incredible success of the P-51 Mustang during the Second World War, it’s perhaps no surprise that the United States entertained the idea of combining two of the iconic fighters on the same wing to create a long-range fighter that could escort bombers into Japan. But the war ended before the F-82 “Twin Mustang” became operational, and the advent of jet fighters ultimately made the idea obsolete. Just five examples of this unique piece of history are known to exist, and the
only one in airworthy condition can now be yours
.
Assuming you’ve got $12 million laying around, anyway. Even for a flyable WWII fighter, that’s a record setting price tag. But on the other hand, you’d certainly be getting your money’s worth. It took over a decade for legendary restoration expert [Tom Reilly] and his team to piece the plane, which is actually a prototype XP-82 variant, together from junkyard finds. Even then, many of the parts necessary to get this one-of-a-kind aircraft back in the sky simply no longer existed. The team had to turn to modern techniques like CNC machining and additive manufacturing to produce the necessary components, in some cases literally mirroring the design in software so it could be produced in left and right hand versions.
Recovering half of the Twin Mustang in 2008.
We
first covered this incredible restoration project back in 2018
, before the reborn XP-82 had actually taken its first flight. Since then the plane has gone on to delight crowds with the sound of two counter-rotating Merlin V-12 engines and win several awards at the Oshkosh airshow. The listing for the aircraft indicates it only has 25 hours on the clock, but given its rarity, we can’t blame [Tom] and his crew for keeping the joyrides to a minimum.
As important as it is to
make sure these incredible pieces of engineering aren’t lost to history
, the
recent crash of the B-17G
Nine-O-Nine
was a heartbreaking reminder
that there’s an inherent element of risk to flying these 70+ year old aircraft. A world-class restoration and newly manufactured parts doesn’t remove the possibility of human error or freak weather. While we’d love to see and hear this beauty taxiing around our local airport, it’s a warbird that should probably stay safely in the roost. Hopefully the $12 million price tag will insure whoever takes ownership of the world’s only flying F-82 treats it with the respect it’s due. | 18 | 9 | [
{
"comment_id": "6275582",
"author": "CRJEEA",
"timestamp": "2020-09-03T23:15:47",
"content": "Hmm. Upgrade it with plasma stealth and a few other addons. Could be good. :D",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6275588",
"author": "Tom Brusehaver"... | 1,760,373,365.493026 | ||
https://hackaday.com/2020/09/03/a-3d-printed-magnetic-stirrer-for-your-diy-chemistry-projects/ | A 3D Printed Magnetic Stirrer For Your DIY Chemistry Projects | Lewin Day | [
"chemistry hacks",
"Tool Hacks"
] | [
"Chemistry",
"lab equipment",
"laboratory equipment",
"magnetic stirrer"
] | When mixing or agitating delicate solutions in the chemistry lab, a magnetic stirrer is often the tool of choice. They’re able to be easily sterilized and cleaned, while maintaining isolation between the mechanical parts and the solutions in question. While they can be purchased off the shelf,
[Max Siebenschläfer] whipped up a design that can easily be built at home.
The build consists of a 3D printed base, containing a simple brushed motor. This is hooked up to a motor controller fitted with a simple potentiometer for adjusting the speed of rotation. The motor is then fitted with a small 3D printed spinner containing two magnets. A similar 3D printed part acts as a stirrer, and is fitted with a matching pair of magnets, and dropped into the solution. The magnets in the stirrer are attracted to the ones on the end of the motor, and so when the motor spins, the stirrer spins in the solution, with no physical contact required.
It’s a simple way to build a magnetic stirrer at home without having to shell out big money for a laboratory grade unit. We imagine this could be put to fun use for stirring coffee or cocktails, too – if built with a food-grade spinner.
More advanced designs are also possible for the eager home scientist
. Video after the break. | 20 | 7 | [
{
"comment_id": "6275554",
"author": "Tom Brusehaver",
"timestamp": "2020-09-03T20:17:03",
"content": "Could one of those rattle magnets be used as the stirrer?",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6275559",
"author": "Hirudinea",
"... | 1,760,373,367.31541 | ||
https://hackaday.com/2020/09/03/cerebral-palsy-tool-assistant/ | Cerebral Palsy Tool Assistant | Brian McEvoy | [
"Medical Hacks",
"The Hackaday Prize"
] | [
"2020 Hackaday Prize",
"art",
"assistive technology",
"cerebral palsy",
"creativity",
"drawing",
"expression",
"rehabilitation"
] | We all deserve to create. Some people seem to have the muses hidden in their pocket, but everyone benefits when they express themselves in their chose art form. Each of us has tools, from Dremels to paintbrushes, and many folks here build their own implements. Even if we don’t have our macro-enabled mechanical keyboard or a dual-extrusion printer, we can make due. But what if you couldn’t operate your drill, or mouse, or even a pencil? To us, that would be excruciating and is the reality for some. [Laura Roth] and [Christopher Sweeney] are art teachers designing
a tool holder for their students with cerebral palsy
so that they can express themselves independently.
On either side of this banner image, you can see pencil drawings from [Sara], who has spastic cerebral palsy. She made these drawings while wearing the tool holder modeled after her hand. Now, that design serves other students and is part of the 2020 Hackaday Prize. The tool holder wraps around the wrist like a wide bracelet. Ribbing keeps its shape, and a tube accepts cylindrical objects, like pencils, styluses, and paintbrushes.The result is that the tip of the pencil is not far from where it would have been if held in the hand, but this sidesteps issues with grip and fine control in hands and fingers.
The print is available as an STL and should be printed with flexible filament to ensure it’s comfortable to wear. Be mindful of digital styluses which may need something conductive between the barrel and user.
Hackers are familiar with the challenges of cerebral palsy, and we’ve enjoyed seeing a variety of solutions over the years like
door openers
,
camera gimbals
, and just being altogether
supportive
.
The
Hackaday
Prize2020
is Sponsored by: | 2 | 2 | [
{
"comment_id": "6275542",
"author": "Ren",
"timestamp": "2020-09-03T19:53:37",
"content": "Bravo!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6275623",
"author": "Sandi",
"timestamp": "2020-09-04T04:37:30",
"content": "Thank you for looking for... | 1,760,373,367.065681 | ||
https://hackaday.com/2020/09/03/the-astronomical-grit-of-ronald-mcnair/ | The Astronomical Grit Of Ronald McNair | Kristina Panos | [
"Biography",
"Featured",
"History",
"Original Art"
] | [
"Challenger",
"laser",
"laser physics",
"mit",
"nasa",
"saxophone",
"Space Shuttle"
] | There is more than one way to lead a successful life. Some people have all the opportunity in the world laid out before them, and it never does them any good. Others have little more than the determination and desire they’ve dredged up within themselves, and that grit turns out to be the abrasive that smooths the path ahead.
Ronald McNair succeeded despite poverty, racism, and an education system designed to keep Black people down. He became an accidental revolutionary at the age of nine, when he broke the color barrier in his small South Carolina town via the public library. This act of defiance in pursuit of education would set the course for his relatively short but full life, which culminated in his career as a Space Shuttle mission specialist.
Rule-Breaker with a Slide Rule
Ronald McNair was born October 21, 1950 in Lake City, South Carolina, the second of three sons, to Pearl and Carl McNair. His mother was a teacher, and encouraged his love of reading. Ronald’s father, Carl was an auto mechanic who never finished high school and always regretted it. Though the family was poor, Ron grew up surrounded by books, music, and support.
Ronald learned to read by the time he was three years old, and his father forged his birth certificate so he could start school at age four. From a young age, he was obsessed with science fiction, space, and Sputnik in particular. Even though the house was filled with books, there was one book that Ron didn’t have: the one that told him much more about his prized slide rule than the pamphlet that came with it.
The original Lake City library building, now known as the Ronald E. McNair Life History Center. Image via
ArtFields
In the summer of 1959 he located the book in the Lake City public library. There was only one problem: the library was segregated, and he wasn’t allowed check it out. Nine-year-old Ron didn’t abide, so he simply refused to leave the library until they let him check out his stack of books. First the librarians called the cops, and then they called his mother.
Pearl McNair arrived to find her son sitting on the checkout counter, his little legs dangling down the side. Since he wasn’t causing any real trouble, she proudly stood by her son in the matter, telling the librarians that they ought to just let him check out the books. From that day on, Ron could check out books whenever he wanted.
Ronald was determined in every aspect of his life, and his well-rounded personality is like something out of fiction. Throughout school, he was serious about his studies to the point of being competitive. Ron competed with his friends for the best grades, and won most of the time. In high school, Ron played baseball, football, basketball, and ran track. He also excelled in music, starting on the clarinet and settling on the saxophone. In spite of all these talents and obligations, Ron still found time to be social and was well-liked. To the surprise of probably no one, Ron graduated as class valedictorian.
Ron in the MIT physics lab. Image via
Oxford American
A Laser Focus
Lake City stood firmly in the segregated South, but inequality wasn’t something Ron focused on. Still, it affected him. He couldn’t just apply to whatever college he wanted, no matter how good his grades were. And even though Ron had excellent and supportive high school teachers, the “separate but equal” doctrine meant that his education was not as robust or varied as that of white students.
After high school, Ron got a scholarship to the closest college that offered physics to Black students — North Carolina Agricultural and Technical State University in Greensboro. He entered as a music major, but after speaking with a guidance counselor, he switched to physics.
Ronald had to work particularly hard because of the gaps in his underfunded education. But he still found time to be well-rounded. Freshman year he started learning Tae Kwon Do, eventually becoming a fifth-degree black belt and a teacher.
Ron went to MIT for two semesters as part of an exchange program that was designed to get students of color to pursue the sciences. Once he earned his bachelor’s degree in physics from North Carolina A&T, Ronald returned to MIT for his graduate degree. He had to study harder than ever, and confront racism head on at the same time. Ron had a couple of bad experiences in Cambridge. Once he was pursued by a group of men and jumped by one of them. Another time, someone sicced their dog on him.
Ron the martial artist. Image via
Oxford American
The Physics of Tae Kwon Do
At MIT, Ron focused his doctoral thesis on laser physics. He helped make some of the first chemical and high-pressure carbon dioxide lasers in the MIT physics lab. He failed his first attempt at the five-hour long PhD exam. Then, he lost a notebook with two years of notes in it. He had to redo all of his lab work, but ended up with even better notes the second time and passed the exam.
Around the time he
co-wrote an article for
Scientific American
about the physics of tae kwon do
(PDF), Ron met his future wife, Cheryl at a church potluck, and they got married after graduation. Ron got a job as a staff physicist at Hughes Research Laboratories, a center for advanced laser research in Malibu, California. One of his duties was laser research for communication between satellites.
The following year, Ron got a targeted brochure in the mail from NASA, who were looking for mission specialist candidates. He gleefully applied, encouraged by Cheryl. Ron and 34 other people were accepted from a pool of 10,000 applicants.
Space Saxophonist
Ron spent six years in astronaut training before his first mission on the Space Shuttle
Challenger
. In the meantime, he and Cheryl had two children, Reginald and Joy. At the end of his training, Ron was assigned to the orbiter’s fourth mission, STS-41-B, which launched on February 3rd, 1984. The mission included the first-ever untethered spacewalk, and Ron made history as the second African-American in space.
The mission’s main objectives were putting a pair of satellites into orbit and testing new equipment. For his part, Ron was assigned to do experiments with solar cells and pneumatic conveyors, operate a gas spectrometer focused on the orbiter, and use the remote sensing camera to take pictures of Earth. He was also in charge of operating the new 50-foot mechanical arm that was designed to snatch satellites and bring them in for repair. Ron had another, secret objective: playing the saxophone in space. In the months leading up to liftoff,
he had several discussions with a music store owner
to research how space jazz might work. He sneaked a soprano saxophone on board and blew a solo rendition of “What the World Needs Now is Love”. As far as anyone knows, Ron McNair was the first person to play a saxophone in space.
Ron experiments with space jazz. Image via
MIT
Ron received quite the reception when he returned to Lake City. There were celebrations, parades, and a street renaming in his honor. Most notably, Ron’s boot prints were set in concrete at a park that once forbade Black people. He gave talks at MIT and elsewhere, always making sure that young students, especially of color, were invited to them.
Two years later, Ron was scheduled to return to space on the ill-fated
Challenger
mission in 1986. He was planning to record a sax solo for a Jean-Michel Jarre album on the shuttle, having proven the viability of the instrument away from Earth. He lost his life along with six other crew members when the shuttle broke apart during launch the morning of January 28th, 1986.
Since the tragedy, many buildings and schools have been named in the honor of the seven men and women whose lives were cut short that cold January morning. MIT dedicated the building that houses the Center for Space Research after Ron. In 2011, the Lake City library was rebuilt, and the original building was turned into the Ronald E. McNair Life History Center. Anywhere a kid can be found trying to rise above their circumstances, Ron’s spirit lives on. | 23 | 16 | [
{
"comment_id": "6275512",
"author": "Antron Argaiv",
"timestamp": "2020-09-03T18:11:17",
"content": "Damn. Heck of a story about a heck of a man…and the power of access to a library.We lost a good one. Ad astra.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id"... | 1,760,373,367.380308 | ||
https://hackaday.com/2020/09/03/linux-fu-moving-usr/ | Linux Fu: Moving /usr | Al Williams | [
"Hackaday Columns",
"Linux Hacks",
"Skills"
] | [
"Intel Compute Stick",
"linux",
"systemd"
] | Linux has changed. Originally inspired by Unix, there were certain well understood but not well enforced rules that everyone understood. Programs did small things and used pipes to communicate. X Windows servers didn’t always run on your local machine. Nothing in
/usr
contributed to booting up the system.
These days, we have systemd controlling everything. If you run Chrome on one display, it is locked to that display and it really wants that to be the local video card. And moving
/usr
to another partition will easily prevent you from booting up, unless you take precautions. I moved
/usr
and I lived to tell about it. If you ever need to do it, you’ll want to hear my story.
A lot of people are critical of systemd — including me — but really it isn’t systemd’s fault. It is the loss of these principles as we get more programmers and many of them are influenced by other systems where things work differently. I’m not just ranting, though. I recently had an experience that brought all this to mind and, along the way, I learned a few things about the modern state of the boot process. The story starts with a friend giving me an Intel Compute Stick. But the problems I had were not specific to that hardware, but rather how modern Linux distributions manage their start-up process.
The Story
As I said, a friend of mine gave me an Intel Compute Stick. It was one of the early ones that was fairly anemic. In particular, it only had 1 GB of memory and 8 GB of flash storage. It booted an old version of Ubuntu and it was, as you’d expect, pretty slow. But I liked the form factor and I have a new workshop that could use a permanent PC, so I decided to upgrade it.
There were the usual problems. A BIOS upgrade broke the network. Upgrading to KDE Neon fixed the network, but the newer kernel had the dreaded C-State bug that caused hangs. Luckily, that’s easy to workaround. So after some effort, I had a reasonably working system. Sort of.
The Problem
The problem was the 8GB of flash. I put a 64GB SDCard in, but I didn’t want to boot from it. With Neon installed and a few other essential things, the flash was very close to 100% full. My plan was to move
/opt
,
/home
, and
/usr
over to the SDCard. I thought it would be easy.
Traditionally, this is a straightforward process. First, copy the files over using something that gets hidden files and links without changing them. Many people use rsync but usually use tar. Then you remove the old directory (I rename it first, just to be safe and delete it after everything is working). Finally, you make a new empty directory and change
/etc/fstab
to mount the disk at boot time.
For
/home
and
/opt
that was fine. The system will boot without difficulty and I had that working in no time. I knew
/usr
would be a bit harder but I figured I could be in a root shell without the GUI or just boot off a USB drive and do all the same work.
I actually anticipated four mounts. I mounted the entire SDCard at
/sdcard
. Then I did bind mounts from
/sdcard/opt
to
/opt
and
/sdcard/home
to
/home
. The
/usr
mount would also be a bind mount but it wasn’t going to be that easy.
The Bigger Problem
My attempts to move
/usr
caused the system to stop booting. Why? Turns out systemd handles mounting what’s in
/etc/fstab
and systemd requires things in
/usr
. I thought perhaps that systemd would be smart enough to boot the system if it didn’t have to read
/etc/fstab
so I decided to mount the SDCard using systemd’s native facilities.
Systemd can handle a mount just like a service. That means it will manage the mounting, and also weave it into the dependencies. So it is possible to require a service or other mount to be ready before mounting some disk and, of course, other services and mounts might depend on that disk, as well. In theory, that’s perfect because it doesn’t make sense to try to mount
/sdcard/home
, for example, before mounting
/sdcard
.
Here’s the mount definition in
/etc/systemd/system/sdcard.mount
[Unit]
Description=Main SDCard Mount
DefaultDependencies=no
Conflicts=umount.target
Before=local-fs.target umount.target
After=swap.target
[Mount]
What=/dev/disk/by-uuid/b3b6ac3b-2109-487c-af34-c49586412cea
Where=/sdcard
Type=ext4
Options=defaults,errors=remount-ro
[Install]
WantedBy=multi-user.target
Obviously, the UUID would change depending on your disk. Not so obviously, this file must be named sdcard.mount. If the mount point were, say,
/usr/lib
then the file would have to be usr-lib.mount.
Once that mount occurs, you can mount
/home
:
[Unit]
Description=Home SDCard Mount
DefaultDependenices=no
Conflicts=umount.target
Before=local-fs.target umount.target
RequiresMountsFor=/sdcard
[Mount]
What=/sdcard/home
Where=/home
Type=none
Options=bind,x-systemd.requires-mounts-for=/sdcard
[Install]
WantedBy=multi-user.target
Note that the mount requires
/sdcard
. Once you put these files in the right place and reload systems, you can start these units and the files will mount. You can enable them to cause them to start at boot. The
/opt
unit looks just the same, except for the file names.
Not So Fast!
This still leaves the problem with
/usr
. Oh sure, it is easy to write the unit, but the problem is that systemd needs some libraries out of
/usr
so the system will refuse to boot. I considered copying the libraries over to either
/lib
or somewhere in the initial RAM disk, but after it turned out to be quite a few, I decided against that.
I finally decided that having everything mounted early in the boot process would be the right answer. That way systemd can imagine it has a complete disk. I had actually considered using lvm to join the disks together, but decided that was bad for a lot of reasons and may have had the same problems anyway. I wanted control over what was on the SDcard vs the internal storage, so it was time to look at the initramfs scripts.
Booting (Some) Linux Systems
Most modern Linux distributions don’t boot your root file system directly. Instead, they have a compressed file system that loads into RAM and then boots. This system is responsible for getting the system ready for the real boot. Among other things, it mounts the root file system and then pivots to make it the real root.
For Debian-style distributions, this is the initramfs and you can find some user-definable scripts in
/etc/initramfs-tools
. The bulk of the predefined ones are in
/usr/share/initramfs-tools
. In the scripts directory you’ll see a number of subdirectories with suffixes of -top, -bottom, and -premount.
As you might imagine, init-* occurs at system initialization and local-* happens as local disks are mounted. Don’t confuse these with hook scripts. A hook script executes when you are building the initial file system. That helps if you need to modify the boot environment statically. The scripts we want are the ones that execute at boot time.
The top scripts run first, followed by the premount, and then the bottom. So init-top runs first and init-bottom is the last thing that runs. In between, the other scripts run and by local-bottom, the root file system should be ready to go.
Documentation and Gotchas
If you read the
documentation
, you’ll see that the scripts have a specific format. However, there are some examples that are misleading. For example, the template script shows sourcing
/usr/share/initramfs-tools/hook-functions
to load common functions. That’s great if
/usr
already exists, but for us it doesn’t. Some other scripts use a copy that is in the boot environment, located at
/usr/share/initramfs-tools/scripts/functions
. That’s what I used in my script:
#!/bin/sh
PREREQ=""
prereqs()
{
echo "$PREREQ"
}
case $1 in
prereqs)
prereqs
exit 0
;;
esac
. scripts/functions
# Note: our root is on /root right now, not /
mount /dev/mmcblk2p1 /root/sdcard
mount -o bind /root/sdcard/usr /root/usr
mount -o bind /root/sdcard/home /root/home
mount -o bind /root/sdcard/opt /root/opt
The only tricky part is that our eventual root file system isn’t at
/
, it is at
/root
, so the mounts reflect that.
The Result
Of course, I had to disable the systemd mounts for
/opt
and
/home
although I could have left them and not put them in this script. Now by the time systemd gets control it can find all the things in
/usr
it wants and the system boots. Moving those three directories left me with about 70% of the internal storage free and only took up a small fraction of the SDCard.
There are probably many other ways to do this. I mentioned lvm or you could revert back to the old init scripts. But this does work reliably and is very flexible once you get it all figured out.
The Intel stick is pretty small, but we’ve
seen smaller
. If you do try this at home, don’t forget that logging to eMMC devices
isn’t always a good idea
. | 83 | 27 | [
{
"comment_id": "6275438",
"author": "shinsukke",
"timestamp": "2020-09-03T14:47:22",
"content": "I tried something similar for my OrangePi PC board. The SD card I had at hand was very slow, and only 4GB, so I decided to use a 500GB USB harddrive as my main storage instead. I promptly copied the /us... | 1,760,373,367.622375 | ||
https://hackaday.com/2020/09/04/approaching-the-drop-location-seeds-away/ | Approaching The Drop Location: Seeds Away! | Brian McEvoy | [
"drone hacks",
"The Hackaday Prize"
] | [
"FLORA",
"forest",
"native seeds",
"planting",
"reforestation",
"seeds",
"trees",
"wilderness restoration",
"wildlife"
] | Arbor Day is a holiday many countries dedicate to planting trees, but with the steady encroachment of climate change, we need to maximize our time.
Dronecoria doesn’t just plant a tree
; it sows “hectares in minutes.” A hectare is 10,000 square meters or 2.471 acres. These aren’t the drones you’re looking for if you intend a weekend of gardening, this is in the scope of repopulating a forest with trees or reinvigorating a park with wildflowers. The seed balls in the hopper are 10kg of native seeds coupled with beneficial microorganisms to help the chances of each drop.
The drone’s body is laser cut from what looks like baltic birch plywood. The vector files are available in Illustrator (.ai) and CAD (.dxf) formats released under Creative Commons BY-SA, so give credit if you redistribute or remix it. In the 3D realm, you’ll need a SeedShutter and SeedDisperser, and both models are available in STL format.
We have other
non-traditional seed spreading methods
like canons, but
it is a big job
, and if you’ve build something to pitch in,
drop us a tip
!
The
Hackaday
Prize2020
is Sponsored by: | 8 | 4 | [
{
"comment_id": "6275777",
"author": "Dan",
"timestamp": "2020-09-04T18:54:07",
"content": "For the moment I thought they were dropping 10kg balls. Then I realised you meant 10kg of small seed balls.Both are impressive in terms of load capacity, but the former is very scary!",
"parent_id": null,... | 1,760,373,367.258375 | ||
https://hackaday.com/2020/09/04/retrotechtacular-forging-in-closed-dies/ | Retrotechtacular: Forging In Closed Dies | Jenny List | [
"Retrotechtacular"
] | [
"drop forging",
"forging",
"metalwork"
] | It is the norm for our
Retrotechtacular
series to concentrate on a technology that has passed out of use but is still of interest to Hackaday readers, so it is perhaps unusual now to feature one that is very much still with us. Drop forging is a technique for forming hot metal in dies under huge force, and while it is still a current technique
the 1950s educational film
we are featuring is definitely retro.
An automotive connecting rod, sectioned and acid treated to show the grain structure. (
CC BY-SA 2.5
)
If you have followed
our occasional series on blacksmithing
, you’ll be familiar with the process of forming metal by heating it to a temperature at which it becomes malleable enough to deform under pressure, and using a hammer to shape it against an anvil. This process not only shapes the metal, but also forms its inner grain crystal structure such that with careful management the forging process can impart significant resistance to fatigue in the finished item. Think of drop forging as automation of the manual blacksmithing process, with the same metallurgical benefits but in which the finished product is shaped in a series of dies rather than by the blacksmith’s hammer. It loses the craft of the smith over the process, but delivers an extremely consistent result along with a high production turnover.
The film that we’ve placed below the break is an in-depth introduction to the industry in a very period style and with components for the automotive, aerospace, and defense industries of the day. It takes the viewer through the different types of press and examines the design of dies to produce in stages the required grain structure and shapes.
Of particular interest is the section on upset forging, a technique in which a piece of steel stock is forged end-on rather from above. The components themselves make the video worth watching, as we see everything from jet turbine blades to medical forceps in production, along with many parts from internal combustion engines. The smallest piece shown is a tiny carburetor part, while the largest is a huge aircraft carrier catapult part that requires a special vehicle to load it into the press.
Drop forging is generally the preserve of a large metalworking factory due to the size of the presses involved. But it’s not entirely beyond the capabilities of our community given the resources of a well-equipped hackerspace or blacksmith’s shop. My father made simple forging dies by assembling a basic shape in weld and pieces of steel stock before grinding it to his requirements and heat treating. Mounted in a large rotary fly press for repetitive small scale shaping and forming tasks in ornamental ironwork, I remember bumping them out from red hot steel bar in my early teens.
This is one of those techniques that’s useful to know about in our community, because while the need to manufacture significant quantities of ornamental ironwork may not come your way too often, it’s still worth having the capability should you need it. Meanwhile the video below the break should serve to provide you with enough heavy machinery enjoyment to brighten your day.
Thanks [Ian Somers] for the tip. | 16 | 10 | [
{
"comment_id": "6275756",
"author": "Bob",
"timestamp": "2020-09-04T17:11:24",
"content": "Hard by my high school was a major tool maker that ran a drop forge. All day long you could feel the vibration of wrenches being brought into the world. Thanks for the memories…",
"parent_id": null,
"... | 1,760,373,367.207928 | ||
https://hackaday.com/2020/09/04/hackaday-podcast-083-soooo-many-custom-peripherals-leaving-bluetooth-footprints-and-a-twirlybird-on-mars/ | Hackaday Podcast 083: Soooo Many Custom Peripherals, Leaving Bluetooth Footprints, And A Twirlybird On Mars | Mike Szczys | [
"Hackaday Columns",
"Podcasts"
] | [
"audio analyser",
"covid tracing app",
"Hackaday Podcast",
"jet pack",
"Joystick",
"mars helicopter",
"nintendo wi",
"parts",
"rc controller",
"thingiverse"
] | Hackaday editors Mike Szczys and Elliot Williams ogle the greatest hacks from the past 168 hours. Did you know that Mars Rover didn’t get launched into space all alone? Nestled in it’s underbelly is a two-prop helicopter that’s a fascinating study in engineering for a different world. Fingerprinting audio files isn’t a special trick reserved for Shazam, you can do it just as easily with an ESP32. A flaw in the way Bluetooth COVID tracing frameworks chirp out their anonymized hashes means they’re not as perfectly anonymized as planned. And you’re going to love these cool ways to misuse items from those massive parts catalogs.
Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Direct download
(60 MB or so.)
Where to Follow Hackaday Podcast
Places to follow Hackaday podcasts:
iTunes
Spotify
Stitcher
RSS
YouTube
Check
out our Libsyn landing page
Episode 083 Show Notes:
New This Week:
“A Guy In A Jet Pack” Reported Flying Next To Aircraft Near LAX
Service on Thingiverse has been touch and go this week
How to download zip of the files when the page won’t load
3D Printering: The Search For Better Search
A Cyclopic LCD Case For Your Raspberry Pi Server
Interesting Hacks of the Week:
Hacker Driven To Build R/C Forza Controller
COVID-tracing Framework Privacy Busted By Bluetooth
3D-Printed Flight Controls Use Magnets For Enhanced Flight Simulator 2020 Experience
Olaf Lets An ESP32 Listen To The Music
Olaf – Acoustic fingerprinting on the ESP32 and in the Browser – 0110.be
How the Shazam algorithm works
(PDF)
Mil-Spec Looks Without Defense Department Budget
WiiBoy Color Is Exactly What It Sounds Like
Quick Hacks:
Mike’s Picks:
Solar Satellite Glows At Night
TritiLED shines green LED for years on one coin cell
Perfect Photographs For PCB Reverse Engineering
A 3D Printed Paint Mixer
Elliot’s Picks:
Don’t Slack Off On Updating Your Status
Building An Open Source ThinkPad Battery
Staged Train Wrecks: An Idea That Ran Out Of Steam
Can’t-Miss Articles:
An Up-Close Look At The First Martian Helicopter
The B-Sides: Curious Uses Of Off-the-Shelf Parts
How To Build Anything Using Delrin And A Laser Cutter
How To Build Anything Out Of Aluminum Extrusion And 3D Printed Brackets | 3 | 2 | [
{
"comment_id": "6276306",
"author": "Elliot Williams",
"timestamp": "2020-09-07T12:03:23",
"content": "A listener wrote in.The RC controller in the story that Mike featured was sadly made by a company not called Dumb Orc, but rather Dumbo RC.My dreams are crushed. But I’m making stickers for all m... | 1,760,373,367.671858 | ||
https://hackaday.com/2020/09/04/an-arduino-controller-for-hot-air-handles/ | An Arduino Controller For Hot Air Handles | Tom Nardi | [
"Arduino Hacks",
"Tool Hacks"
] | [
"858D",
"arduino pro mini",
"hot air rework station",
"soldering"
] | In general, the cost of electronic components and the tools used to fiddle with them have been dropping steadily over the last decade or so. But there will always be bargain-hunting hackers who are looking to get things even cheaper. Case in point, hot air rework stations. You can pick up one of the common 858D stations for as little as $40 USD, but that didn’t keep [MakerBR] from
creating an Arduino controller that can be used with its spare handles.
Now to be fair, it doesn’t sound like price was the only factor here. After all, a spare 858D handle costs about half as much as the whole station, so there’s not a lot of room for improvement cost-wise. Rather, [MakerBR] says the Arduino version is designed to be more efficient and reliable than the stock hardware.
The seven wires in the handle connector have already been mapped out by previous efforts, though [MakerBR] does go over the need to verify everything matches the provided circuit diagrams as some vendors might have fiddled with the pinout. All the real magic happens in the handle itself, the controller just needs to keep an eye on the various sensors and provide the fan and heating element with appropriate control signals. An Arduino Pro Mini is more than up to the task, and a custom PCB makes for a fairly neat installation.
This isn’t the first time we’ve seen
somebody replace the controller on one of these entry-level hot air stations
, but because there are so many different versions floating around, you should do some careful research before cracking yours open and performing a brain transplant. | 3 | 2 | [
{
"comment_id": "6275739",
"author": "Brian",
"timestamp": "2020-09-04T15:51:34",
"content": "Uh, you might wanna put a fuse or two in there, somewhere.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6275744",
"author": "philosiraptor117",
"t... | 1,760,373,367.108171 | ||
https://hackaday.com/2020/09/04/this-week-in-security-zero-days-notarized-malware-jedi-mind-tricks-and-more/ | This Week In Security: Zero Days, Notarized Malware, Jedi Mind Tricks, And More | Jonathan Bennett | [
"Hackaday Columns",
"News",
"Security Hacks"
] | [
"credit card fraud",
"honeypot",
"macOS",
"This Week in Security"
] | Honeypots are an entertaining way to learn about new attacks. A simulated vulnerable system is exposed to the internet, inviting anyone to try to break into it. Rather than actually compromising a deployed device, and attacker just gives away information about how they would attack the real thing. A honeypot run by
360Netlab found something interesting back in April
: an RCE attack against QNAP NAS devices. The vulnerability is found in the logout endpoint, which takes external values without properly sanitizing them. These values are used as part of an
snprintf
statement, and then executed with a
system()
call. Because there isn’t any sanitization, special characters like semicolons can be injected into the final command to be run, resulting in a trivial RCE.
QNAP has released new firmware that fixes the issue by replacing the
system()
call with
execv()
. This change means that the shell isn’t part of the execution process, and the command injection loses its bite. Version 4.3.3 was the first firmware release to contain this fix, so if you run a QNAP device, be sure to go check the firmware version. While this vulnerability was being used in the wild, there doesn’t seem to have been a widespread campaign exploiting it.
Notarized Malware
Once upon a time, it was reasonably accurate to say that Mac machines didn’t get viruses. Strictly speaking, that hasn’t been true since 1987, when nVIR was discovered traveling on floppy disks and infecting Macintosh machines. Regardless, as Macs have gotten more popular, and as Microsoft has slowly improved the security of Windows systems, it’s becoming less and less accurate to say that Macs don’t get viruses. In response, Apple has introduced Code Notarization for macOS, a system where developers submit their apps to Apple for review. After the app has been verified to be non-malicious, it’s signed with Apple’s key, and will run on a Mac machine without needing any special steps.
The problem is the inherent difficulty in determining whether a program is malicious, just through static analysis. Apple seems to be signing almost all requests, and simply revoking signatures of apps that prove to be malicious. [Patrick Wardle] from Objective-See brings us the report of
an active Mac malware campaign that’s using notarized malware
. The situation was reported to Apple, who quickly revoked the signatures. Within 48 hours, the malware campaign once again had notarized malicious binaries. It remains to be seen how the situation will resolve, but for now, it seems like notarized code isn’t a very good indicator of trustworthy code.
You Don’t Need to see My Identification
Contactless payments are impressive. Just wave a credit card over a payment terminal, and a cryptographic handshake confirms that you really have the credit card. In the case of high value transactions, a PIN is also required. The protocol that powers this is EMV, named for Eurocard, Mastercard, and Visa, the corporations that cooperated to develop the standard. Researchers at ETH Zurich took a look at that protocol, and
published a paper about some flaws they found (pdf)
. The attack I found most interesting is the “Jedi Mind Trick” they pulled off using a pair of cell phones as intermediaries. The attack is a simple man-in-the-middle where a few bytes are changed in transit. These bytes instruct the payment terminal not to require a PIN entry, even for very large purchases.
Be Careful Compiling Secrets
The reason that security is so difficult is that there’s just so many ways to mess it up. This time, we’re talking about static keys that get compiled into released software.
[Abss] got curious about Android security, and started working on a project.
He grabbed as many APKs as he could get hands hands on, and decompiled them. From there, a clever
grep
search for variables and strings resulted in a bunch of interesting hits, like Google API keys.
That was all well and good, but it seemed like there should be something interesting that could be done with the harvested keys. The answer was the Firebase Cloud Messaging service, by Google. A valid key FCM server key and a bit of boolean trickery allows sending a message to every user of an app. It’s not hard to imagine that many applications are written with the assumption that the incoming FCM messages are trustworthy. Breaking that assumption leads to all sorts of problems, including RCE in four of Google’s official apps.
Cisco Jabber
Jabber is a messenger service, built on top of the XMPP. Cicso provides a proprietary jabber that
was recently discovered to be vulnerable to a serious RCE attack
. The vulnerability boils down to a cross-site-scripting filter that works in a blacklist mode, and doesn’t successfully block everything it should. The filter could be bypassed by sending an img element with the
onanimationstart
attribute.
Because the vulnerability can be triggered with a single message, it’s also considered a wormable vulnerability, and so scored a 9.9 severity. This issue was reported privately, and an updated version is now available with fixes, so if your organization uses Cisco Jabber, make sure it gets updated!
When The Code Stares Back
If there is a perverse pleasure in finding vulnerabilities in security products, then there must be doubly so for finding them in vulnerability scanners themselves. And that is exactly what [Gabor Mutuz] found himself doing —
trying to break vulnerability scanners
. As complex as modern containerized applications are, it’s not surprising that it’s possible to trip up a vulnerability scanner.
While it might seem like useless vulnerability research, consider that some projects have these scanners plugged into their continuous integration pipeline. I’ve seen some projects that even run the CI checks on every pull request. It’s not an attack vector that’s normally considered, but it’s extremely important that even these tools are hardened for security. [Gabor] reported the issues he found, and they’ve been fixed in subsequent updates. Be sure to go check out his post about it for all the details. | 5 | 3 | [
{
"comment_id": "6275718",
"author": "dudeguy",
"timestamp": "2020-09-04T14:43:47",
"content": "Okay, so the thing about android apps having their API keys easily read is frightening. Not that I know anything, but those should probably be in some sort of backend, no?",
"parent_id": null,
"de... | 1,760,373,367.153508 | ||
https://hackaday.com/2020/09/04/autonomous-off-road-food-delivery-with-pixhawk/ | Autonomous Off-Road Food Delivery With Pixhawk | Tom Nardi | [
"Robots Hacks"
] | [
"autonomous rover",
"PixHawk",
"rc truck",
"rover",
"self-driving",
"traxxas"
] | It should come as no surprise that the COVID-19 pandemic has sparked renewed interest in robotic deliveries. Amazon saying they would some day land Prime orders in your backyard with a drone sounded pretty fanciful a few years ago, but now that traditional delivery services are under enormous strain and people are looking to avoid as much human contact as possible, it’s starting to make a lot more sense.
Pro Tip: Avoid drifting while towing seafood.
Now to be clear, we don’t think you’ll be
seeing this modified RC truck rolling up your driveway with a pizza
in tow anytime soon. But the experiments that [Sean] has been doing with it are certainly interesting, and show just how far autonomous rover technology has progressed at the hobbyist level. Whether you need to move some sushi or a sensor package, his build is a great starting point for anyone interested in DIY robotic ground vehicles.
Especially if you want to take things off the beaten path once and awhile. By combining the Pixhawk autopilot system with an off-road RC truck by Traxxas, [Sean] has created a delivery bot that’s not afraid of a little mud. Or even the occasional jump, should the need arise. Just don’t expect your shrimp cocktail and champagne to arrive in one piece after they’ve been given the
Dukes of Hazzard
treatment.
In the video after the break [Sean] goes over some of the lessons learned on this build, including how he managed to keep the electronics from cooking themselves in the Texas heat. He also goes over the realities of building an autonomous driving system that doesn’t actually have a camera onboard; sure you can plan a route for it in advance, but all bets are off if an unexpected obstacle blocks the path. It’s a pretty serious shortcoming he’s looking to address in the future, as well as
upgrading to a far more accurate RTK-GPS receiver
. | 1 | 1 | [
{
"comment_id": "6275759",
"author": "james",
"timestamp": "2020-09-04T17:15:38",
"content": "My wife loves seafood. How long will it take you to drive to Toronto, Canada?",
"parent_id": null,
"depth": 1,
"replies": []
}
] | 1,760,373,367.71322 | ||
https://hackaday.com/2020/09/04/the-screwdriver-you-dont-need-but-probably-want/ | The Screwdriver You Don’t Need, But Probably Want | Danie Conradie | [
"Crowd Funding",
"Tool Hacks"
] | [
"Crowd Funding",
"Fidget Spinner",
"gaico",
"kinetic driver",
"screwdriver"
] | Screwdrivers are simple devices with a simple purpose, and there is generally little fanfare involved with buying yourself a new set. We’ve never seen one marketed as an object of desire, but we have to admit that [Giaco] managed to do precisely that. He created the
Kinetic Driver
, a
fidget spinner
precision screwdriver designed to use its rotational momentum to loosen and tighten screws.
The main difference between the Kinetic Driver and other screwdrivers is a big brass mass at the front end for high rotational inertia and a high-quality ceramic bearing at the back end for minimal drag. It uses 4 mm precision bits, so its utility will be limited to small screws, which makes it perfect for working on small electronics.
[Giaco] says the
idea
came after running a successful Kickstarter campaign for a utility knife, where he found that his favorite screwdriver for the many small screws was one with a fat metal body which allowed it to spin easily. In the video after the break, he gives an excellent insight into the development process. He started by creating a series of 3D printed prototypes to figure out the basic shape, before making the first metal prototype. [Giaco] also shows the importance of figuring out the order of operation for machining, which is often glossed over in other machining videos. Be sure to check out the beautiful launch video at
17:52
.
It’s difficult to pass judgment on how well the Kinetic Driver would work from [Giaco]’s videos alone, but it looks like it has potential. The friction experienced by any specific screw will be a factor. From the current status of the
Kickstarter campaign at 70x the funding goal
, we hope [Giaco] has the production and supply chain figured out, because he’ll be making a LOT of Kinetic Drivers.
For many applications, especially production, electric screwdrivers might be superior, if you remember to keep them charged of course. We’ve a few
electric screwdrivers
you can
build yourself
. | 50 | 16 | [
{
"comment_id": "6275649",
"author": "Markus",
"timestamp": "2020-09-04T08:45:13",
"content": "You repeatedly use [Gaico] in the text. The creator’s name is Giaco. He is an italian engineer not some american insurance lizard.",
"parent_id": null,
"depth": 1,
"replies": [
{
... | 1,760,373,367.867207 | ||
https://hackaday.com/2020/09/07/miniature-faux-floppy-for-8-bit-atari-looks-the-part/ | Miniature Faux Floppy For 8-Bit Atari Looks The Part | Tom Nardi | [
"Microcontrollers",
"Retrocomputing"
] | [
"atari",
"atmega32u4",
"Disk drive",
"emulator",
"sd card"
] | There’s plenty of fun to be had with retrocomputers of yesteryear, but for modern users, it can be something of a culture shock. Going back to floppy disks after all these years is a reminder of just how far storage technology has come in terms of speed, reliability, and of course, capacity. Luckily, there are ways to combine the best of both worlds.
Floppy drive emulators for classic computers are of course nothing new, but we think
this one [c0pperdragon] has put together is worthy of a closer look
. Not only does the ATmega32U4 based emulator have an exceptionally low part count, but the code has been written in the Arduino IDE. Both features make it easy for new players to duplicate and revise the design should they feel so inclined. In a pinch you could even implement it on a breadboard with a garden variety Arduino.
The emulator is housed in a 3D printed enclosure designed to look like an era-appropriate Atari 1050 Disk Drive, except you’re using SD cards instead of floppies. The firmware can mimic two physical drives and supports up to 100 disk images on each SD card. The user interface is about as simple as it gets, with two push buttons and a pair of seven-segment LEDs to indicate which disk image is currently loaded up.
We’ve seen
some very elaborate disk emulators over the years
, but there’s something compelling about how straightforward this version is. If it helps a few more people experience the unique joys of retrocomputing, it’s a win in our book. | 8 | 5 | [
{
"comment_id": "6276312",
"author": "d3bug",
"timestamp": "2020-09-07T12:46:47",
"content": "Awww… isn’t it just precious… The 1050 drive: “I call it mini-me”",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6276320",
"author": "RW ver 0.0.3",
"timestam... | 1,760,373,367.76635 | ||
https://hackaday.com/2020/09/06/watch-winder-keeps-your-timepieces-ticking/ | Watch Winder Keeps Your Timepieces Ticking | Lewin Day | [
"Misc Hacks"
] | [
"mechanical watch",
"timepiece",
"watch",
"watch winder",
"watches"
] | Mechanical watches are triumphs of engineering on a tiny scale. Capable of keeping time by capturing the energy of the user’s own movements, they never need batteries changed. Unfortunately, they quickly lose time when not worn for a few days. To solve that problem, [sblantipodi]
built a smart watch winder
.
The overall build consists of six individual winder units. Each one has an ESP8266EX D1 Mini microcontroller, hooked up to a 28BYJ48 stepper motor with a ULN2003 motor driver. There’s also an OLED screen for status information. When commanded, the stepper motor turns, rotating a watch case to wind the timepieces. Control is via voice command, thanks to a Google Home Mini and a Raspberry Pi running Home Assistant. Watches can be wound individually, or all together, depending on the command given.
It’s a device that would serve any collector well, and could come in handy for watchmakers to wind customer watches waiting for pickup. Other similar builds have used special silent drives
to ensure the device doesn’t disturb sleep when used on a bedside table.
Video after the break. | 18 | 8 | [
{
"comment_id": "6276238",
"author": "John",
"timestamp": "2020-09-07T05:23:07",
"content": "“Mechanical watches are triumphs of engineering on a tiny scale. Capable of keeping time by capturing the energy of the user’s own movements, they never need batteries changed. Unfortunately, they quickly lo... | 1,760,373,367.93554 | ||
https://hackaday.com/2020/09/06/diy-relay-module-saves-time/ | DIY Relay Module Saves Time | Bryan Cockfield | [
"hardware",
"Parts"
] | [
"driver board",
"efficiency",
"hardware",
"improvements",
"pcb",
"relay",
"switch"
] | As any programmer could tell you, there’s significant value in automating a process that is performed often enough. The more times that process is used, the more it makes sense to automate it or at least improve its efficiency. This rule isn’t limited to software though; improvements to hardware design can also see improvements in efficiency as well. For that reason, [Hulk] designed
a simple relay module in order to cut the amount of time he spends implementing this solution
in his various other projects.
While driving a relay with a transistor is something fundamental, this project isn’t really about that
per se
. It’s about recognizing something that you do too much, and then designing that drudgery out of your projects. [Hulk] was able to design a PCB with 12 modules on it, presumably saving fabrication costs. He can then easily populate them with specific components as soon as he needs one. Another benefit of designing something like this yourself, rather than an off-the-shelf relay module, is that you can do away with any useless features you’ll never need (or add ones that aren’t available in commercial devices).
We can appreciate the
efficiency gains
this would make for our next project that needs a simple driver for a light, garage door opener, or any other binary electronic device. It can be a hassle to go find the correct transistor and relay, solder it all on the project board, and hope it all works. A pre-made solution solves all these issues, but we do wish the schematics were available to keep us from having to design our own.
Driver boards are a pretty common project for all the different types of relays
we see around here, so there is probably one available out there. | 22 | 8 | [
{
"comment_id": "6276215",
"author": "Somun",
"timestamp": "2020-09-07T02:12:32",
"content": "“Another benefit of designing something like this yourself, rather than an off-the-shelf relay module, is that you can do away with any useless features you’ll never need”In this case safety seems to be tha... | 1,760,373,368.235094 | ||
https://hackaday.com/2020/09/06/hackaday-links-september-6-2020/ | Hackaday Links: September 6, 2020 | Mike Szczys | [
"Hackaday Columns",
"Hackaday links"
] | [
"asteroid",
"auto-correct",
"contact tracing",
"flying cars",
"hackaday links",
"low power",
"marble machine"
] | That was a close shave! On Tuesday, asteroid 2011 ES4 passed
really
close to the earth. JPL’s close approach data pegs
its nominal distance from earth
at about 0.00081083276352288 au! Yeah, we had to look it up too: that’s around 75,000 miles (120,000 kilometers), just ten times the diameter of the earth and only about one-third the distance from the earth the moon. It got within about 52,000 miles of the moon itself. Bookworms who made it all the way through
Seveneves
are surely sweating right now.
There’s a low current arms race when it comes to lighting up LEDs.
The latest salvo in the field
comes from [Christoph Tack] who boasts a current of 1.36 µA at 3 V for a green LED that is roughly 10x brighter than a phosphorescent watch dial. Of course, the TritiLED is the design being chased, which claims to run 17.6-20.2 years on a single CR2032 coin cell.
Proving once again that Hanna and Barbera were indeed future-tech prophets, flying cars are now a thing. Sky Drive Inc. made
a four-minute test flight of a single passenger octo-rotor aircraft
. Like a motorcycle of the sky (
and those are a thing too
) this thing is single-passenger and the cockpit is open air. The
CNN article
mentions that “The company hopes to make the flying car a part of normal life and not just a commodity”. Yeah, we’re sure they do, but in an age when electric cars are demonized for ranges in the low hundreds of miles, this is about as practical for widespread use as
self-balancing electric unicycles
.
Just when you thought the Marble Machine X project couldn’t get any bigger, we find out they have
a few hundred volunteers working to update and track CAD models for all parts on the machine
. Want a quick-start on project management and BOM control? These are never seen as the sexy parts of hardware efforts, but for big projects, you ignore them at your own peril.
Google and Apple built a COVID-19 contact tracing framework into their mobile platforms but stopped short of building the apps to actually do the work, anticipating that governments would want to control how the apps worked. So was
the case with the European tracing app as Elliot Williams recently covered in this excellent overview
. However, the United States has been slower to the game. Looks like the tech giants have become tired of waiting and
have now made it possible for the framework itself to work as a contact tracing mechanism
. To enable it, local governments need to upload a configuration file that sets parameters and URLs that redirect to informational pages from local health departments, and users must opt-in on their phone. All other tracing apps will continue to function, this is meant to add an option for places that have not yet adopted/developed their own app.
And finally, it’s time to take back responsibility for your poor spelling. Auto-correct has been giving us sardines instead of teaching how to fish for them ourselves. That ends now. The
Autocorrect Remover
is an extension for Google Docs that still tells you the word is wrong, but hides the correct spelling, gamifying it by having you guess the right spelling and rewarding you with points when you get it right. | 15 | 7 | [
{
"comment_id": "6276191",
"author": "Hirudinea",
"timestamp": "2020-09-06T23:42:23",
"content": "They can’t take away my autocorrect, without it I spell worser than Ralph Wiggum!",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6276216",
"author": "Mi... | 1,760,373,367.998975 | ||
https://hackaday.com/2020/09/06/restoring-an-unusual-piece-of-computing-history/ | Restoring An Unusual Piece Of Computing History | Tom Nardi | [
"computer hacks",
"Retrocomputing"
] | [
"1960s",
"early computer",
"flip-flop",
"paperclip computer",
"restoration",
"transistor logic"
] | Trawling classified ads or sites like Craigslist for interesting hardware is a pastime enjoyed by many a hacker. At a minimum, you can find good deals on used tools and equipment. But if you’re very lucky, you might just stumble upon something really special.
Which is exactly how
[John] came into possession of the TRANSBINIAC
. Included in a collection of gear that may have once belonged to a silent key, the device is a custom-built solid-state computer that appears to have been assembled in the early 1960s. Featuring a large see-through window not unlike what you might find on a modern gaming computer and a kickstand that tilts it back at a roughly 45° angle, it was obviously built to be shown off. Perhaps it was a teaching aid or even a science fair entry.
After some digging, it looks like the design of the TRANSBINIAC was based on plans published in the January 1960 issue of Electronics Illustrated. Though there are some significant differences. This computer uses eight bistable flip-flip modules instead of the original six, deletes the multiplication circuit, and employs somewhat simplified wiring. Whoever built this machine clearly knew what they were doing, which for the time, is really saying something. This truly unique machine may well have been one of the first privately owned digital computers in the world.
Which is why we’re glad to see [John] trying to restore the device to its former glory. Naturally it’s a little tricky since the computer came with no documentation and its design doesn’t exactly match anything out there. But with the help of other Hackaday.io users, he’s hoping to get everything figured out. It sounds like the first step is to try and diagnose the 2N554 germanium transistor flip-flop modules, as they appear to be behaving erratically. If you have experience with this sort of hardware, feel free to chime in.
We’re supremely proud of the fact that so many of these early computer examples (and the people that are fascinated by them) have recently found their way to Hackaday.io. They’re literally the
building blocks on which so much of our modern technology is based on
, and
the knowledge of how they were designed and operated deserves to live on
for future generations to learn from. If it wasn’t for 1960s machines like the TRANSBINIAC or
the so-called “Paperclip Computer”
, Hackaday might not even exist. It seems like the least we can do is return the favor and make sure they aren’t forgotten.
[Thanks to Yann for the tip.] | 46 | 15 | [
{
"comment_id": "6276161",
"author": "Benjy Cline",
"timestamp": "2020-09-06T20:51:16",
"content": "I remember reading the Electronics Illustrated article as a lad. The computer is essentially a binary counter driven by a telephone dial, but I learned a lot from reading the article. I learned abou... | 1,760,373,368.094303 | ||
https://hackaday.com/2020/09/06/pocket-sized-device-sniffs-out-damp-masks/ | Pocket-sized Device Sniffs Out Damp Masks | Tom Nardi | [
"The Hackaday Prize"
] | [
"2020 Hackaday Prize",
"555 timer",
"mask",
"moisture"
] | The realities of wearing a mask when you go out, from forgetting the thing in the car to dealing with fogged up glasses, have certainly taken some getting used to for most of us. But not every issue is immediately obvious. For example, experts say that as a mask gets damp from exhalation or perspiration it becomes less effective. Which is precisely why
[Rick Pannen] has designed the Mask Moisture Meter
.
As deep as we are into the Microcontroller Era, we really appreciate the simplicity of this design. It’s just a 555 timer, a buzzer, some LEDs, and a handful of passive components to get them all talking to each other. There’s no firmware or programming required; just put a fresh battery in the holder and away you go. The traces of the PCB serve as a moisture detector, so when the board is pushed against something wet enough, the red LED and buzzer will go off to warn the user.
Now admittedly, there’s a point where you certainly won’t need an electronic gizmo to tell you a mask is wet. But as [Rick] demonstrates in the video after the break, the circuit is sensitive enough to indicate when there’s moisture in the material that might not be immediately obvious to the eye.
The
Hackaday
Prize2020
is Sponsored by: | 13 | 7 | [
{
"comment_id": "6276136",
"author": "tekkieneet",
"timestamp": "2020-09-06T18:14:14",
"content": "Use ENIG on the “sensor” if you want some level of corrosion resistance. Last thing you want is some electrolysis with solder at a wet spot on the mask as the metal can leech out. You don’t want it o... | 1,760,373,368.16234 | ||
https://hackaday.com/2020/09/06/recognizing-activities-using-radar/ | Recognizing Activities Using Radar | Danie Conradie | [
"Radio Hacks",
"Tech Hacks"
] | [
"activity monitor",
"fmcw radar",
"machine learning",
"mit",
"radar"
] | Caring for the elderly and vulnerable people while preserving their privacy and independence is a challenging proposition. Reaching a panic button or calling for help may not be possible in an emergency, but constant supervision or camera surveillance is often neither practical nor considerate. Researchers from MIT CSAIL have been working on this problem for a few years and have come up with a possible solution called
RF Diary
. Using RF signals, a floor plan, and machine learning it can recognize activities and emergencies, through obstacles and in the dark. If this sounds familiar, it’s because it builds on
previous research by CSAIL
.
The RF system used is effectively f
requency-modulated continuous-wav
e (FMCW) radar, which sweeps across the 5.4-7.2 GHz RF spectrum. The limited resolution of the RF system does not allow for the recognition of most objects, so a floor plan gives information on the size and location of specific features like rooms, beds, tables, sinks, etc. This information helps the machine learning model recognize activities within the context of the surroundings. Effectively training an activity captioning model requires thousands of training examples, which is currently not available for RF radar. However, there are massive video data sets available, so researchers employed a “multi-modal feature alignment training strategy” which allowed them to use video data sets to refine their RF activity captioning model.
There are still some privacy concerns with this solution, but the researchers did propose some improvements. One interesting idea is for the monitored person to give an “activation” signal by performing a specified set of activities in sequence.
Radar is a complex but fascinating topic, and we’ve seen a number of excellent projects in the field, including a
bicycle mounted radar
that can be used to generate aerial images and a
Doppler radar module
designed from first principles.
Thanks [Qes] and [
Adam Conner-Simons
] for the tip! | 10 | 4 | [
{
"comment_id": "6276089",
"author": "Mike",
"timestamp": "2020-09-06T14:11:39",
"content": "“A person enters the kitchen. He takes off his clothes, sits at table and starts playing laptop. ”I don’t know about you, but that line sounds super creepy to me. To sit naked at a table while playing Laptop... | 1,760,373,368.455856 | ||
https://hackaday.com/2020/09/03/covid-tracing-framework-privacy-busted-by-bluetooth/ | COVID-tracing Framework Privacy Busted By Bluetooth | Elliot Williams | [
"News",
"Security Hacks"
] | [
"corona",
"COVID",
"covid tracing app",
"Covid-19",
"news",
"tracing apps"
] | [Serge Vaudenay] and [Martin Vuagnoux] released
a video yesterday documenting a privacy-breaking flaw
in the Apple/Google COVID-tracing framework, and they’re calling the attack “Little Thumb” after a French children’s story in which a child drops pebbles to be able to retrace his steps. But unlike Hänsel and Gretl with the breadcrumbs, the goal of a privacy preserving framework is to prevent periodic waypoints from allowing you to follow anyone’s phone around. (Video embedded below.)
The Apple/Google framework is, in theory,
quite sound
. For instance, the system broadcasts hashed, rolling IDs that prevent tracing an individual phone for more than fifteen minutes. And since Bluetooth LE has a unique numeric address for each phone, like a
MAC address
in other networks, they even thought of changing the Bluetooth address in lock-step to foil would-be trackers. And there’s no difference between theory and practice, in theory.
In practice, [Serge] and [Martin] found that a slight difference in timing between changing the Bluetooth
BD_ADDR
and changing the COVID-tracing framework’s rolling proximity IDs can create what they are calling “pebbles”: an overlap where the rolling ID has updated but the Bluetooth ID hasn’t yet. Logging these allows one to associate rolling IDs over time. A large network of Bluetooth listeners could then trace people’s movements and possibly attach identities to chains of rolling IDs, breaking one of the framework’s privacy guarantees.
This timing issue only affects some phones, about half of the set that they tested. And of course, it’s only creating a problem for privacy within Bluetooth LE range. But for a system that’s otherwise so well thought out in principle, it’s a flaw that needs fixing.
Why didn’t the researchers submit a patch? They can’t. The Apple/Google code is mostly closed-source, in contrast to the open-source nature of
most of the apps that are running on it
. This remains troubling, precisely because the difference between the solid theory and the real practice lies exactly in those lines of uninspectable code, and leaves all apps that build upon them vulnerable without any recourse other than “trust us”. We encourage Apple and Google to make the entirety of their COVID framework code open. Bugs would then get found and fixed, faster. | 60 | 21 | [
{
"comment_id": "6275395",
"author": "John",
"timestamp": "2020-09-03T11:24:44",
"content": "Nice article and good conclusions. I agree completely.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6275620",
"author": "Yurei",
"timestamp": "2020... | 1,760,373,368.41103 | ||
https://hackaday.com/2020/09/03/3d-printed-flight-controls-use-magnets-for-enhanced-flight-simulator-2020-experience/ | 3D-Printed Flight Controls Use Magnets For Enhanced Flight Simulator 2020 Experience | Donald Papp | [
"Arduino Hacks",
"Games",
"Peripherals Hacks"
] | [
"3d printed",
"diy",
"flight simulator",
"hall effect",
"hall effect sensor",
"Joystick",
"pedals",
"throttle"
] | We have seen quite a few DIY joystick designs that use Hall effect sensors, but
[Akaki Kuumeri]’s controller designs
(YouTube video, embedded below) really make the most of 3D printing to avoid the need for any other type of fabrication. He’s been busy using them to enhance his Microsoft Flight Simulator 2020 experience, and shares not just
his joystick design
, but makes it a three-pack with designs for
throttle
and
pedals
as well.
Hall effect sensors output a voltage that varies in proportion to the presence of a magnetic field, which is typically provided by a nearby magnet. By mounting sensors and magnets in a way that varies the distance between them depending on how a control is moved, position can be sensed and communicated to a host computer.
In [Akaki]’s case, that communication is done with an Arduino Pro Micro (with ATmega32U4) whose built-in USB support allows it to be configured and recognized as a USB input device. The rest is just tweaking the physical layouts and getting spring or elastic tension right. You can see it all work in the video below.
Hall effect sensors
have featured in DIY joystick builds
, but for something as delightful as it is different, don’t miss
this fantastic high-speed magnetic imager
based on them. | 23 | 5 | [
{
"comment_id": "6275392",
"author": "alfie",
"timestamp": "2020-09-03T11:23:01",
"content": "Anyone made a sim wheel using that hall effect technique?",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6275408",
"author": "trndr",
"timestamp": "... | 1,760,373,368.313503 | ||
https://hackaday.com/2020/09/02/dont-slack-off-on-updating-your-status/ | Don’t Slack Off On Updating Your Status | Kristina Panos | [
"how-to",
"Lifehacks",
"Microcontrollers"
] | [
"ESP8266",
"rotary switch",
"slack"
] | Displaying an accurate status in Slack (or whatever other employer-provided collaboration program you may be forced to run) is crucial in 2020. If you need to make a sandwich or take the dog out real quick, but you don’t update your status to show yourself as away, you might come back to a string of increasingly concerned or frustrated messages with lots of annoying question marks and the occasional interrobang.
[Becky Stern] decided that a physical interface would be a far more fun way to keep tabs on her status, and an excellent visual reminder to actually do it
. We totally agree. Inside the box is a NodeMCU which is using [Brian Lough]’s Slack API library for Arduino. This made it easy for [Becky] to create a switch/case selector of statuses, and in each of these she can set the presence token as auto or away, and show a custom message with an appropriate emoji. These of course match the emoji semi-circling the selector, which is a rotary switch with a really nice knob.
While we’re on the subject of Slack notifiers,
how about a companion cat to wave when you’ve been mentioned? | 16 | 6 | [
{
"comment_id": "6275332",
"author": "Saabman",
"timestamp": "2020-09-03T05:03:08",
"content": "The dedicated Physical switch nails it.",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6275339",
"author": "Mr Name Required",
"timestamp": "2020-09-03T05:3... | 1,760,373,368.606551 | ||
https://hackaday.com/2020/09/02/fog-free-mask-hack-solves-mask-versus-glasses-conundrum-with-superb-seal/ | Fog-Free Mask Hack Solves Mask Versus Glasses Conundrum With Superb Seal | Brian McEvoy | [
"Medical Hacks"
] | [
"Badger Seal",
"coronavirus",
"COVID",
"Covid-19",
"mask",
"mask fitter",
"seal",
"ventilator"
] | If you have worn a mask and glasses together for more than a quarter of a second, you are probably annoyed that we don’t have a magical solution for foggy lenses. Moisture-laden air is also a good indicator of where unfiltered air is escaping. Most masks have some flexible metal across the nose bridge that is supposed to seal the top, but it is woefully inadequate. The
Badger Seal
by [David Rothamer] and [Scott Sanders] from the University of Wisconsin-Madison College of Engineering is free to copy during the COVID-19 pandemic, even commercially. It works by running an elastic cord below the jaw and a formable wire over the nose to encourage contact all around both mouth and nose.
You can build your own in three ways. Each configuration is uniquely suited to a different situation. The first design is the easiest to make and should work for most people. The second is best for folks who need a better seal on the lower half of their face, like someone sporting a beard. It can also have ear loops, and that means your
3D printed ear savers
have another use.
The Madison campus of the University of Wisconsin also has fun with
lock cracking
and
graphene experiments
.
Badger Seal
takes its name from [Bucky Badger], the school’s mascot. There was no animal testing for this project, but if you can fit a mask on a badger’s face, you can name it whatever you want.
Thank you for the tip, [cyberlass] | 35 | 14 | [
{
"comment_id": "6275314",
"author": "smellsofbikes",
"timestamp": "2020-09-03T02:35:28",
"content": "Maybe this is just the shape of my face, but I put on a paper mask with wire at top, as supplied by my company, bend the wire to fit my nose, then sit my glasses on top of the mask, just over the ed... | 1,760,373,368.672801 | ||
https://hackaday.com/2020/09/02/flipper-zero-blasts-past-funding-goal-and-into-our-hearts/ | Flipper Zero Blasts Past Funding Goal And Into Our Hearts | Tom Nardi | [
"Current Events",
"Tool Hacks"
] | [
"crowd source",
"Flipper One",
"multitool",
"pwnagotchi"
] | There’s never been a better time to be a hardware hacker: the tools are cheap, the information is free, and the possibilities are nearly endless. But that doesn’t mean there isn’t room for improvement.
The Flipper Zero was developed to make the world of hardware hacking even more accessible
, and as of this writing, has officially ended its
Kickstarter campaign after raising a staggering $4.8 million
. To say the community is excited about this little gadget is perhaps an understatement.
So what does the Flipper Zero do that’s gotten everyone so worked up? Well, for one, it’s not so much
what
it can do as
how
it does them. Taking inspiration from
the already popular pwnagotchi project
, the Flipper Zero gamifies the normally rather mundane tasks of sniffing for 433 MHz signals and flashing EEPROMs with the addition of an animated dolphin that’s sustained by your hacking. If you want the little fellow to grow and be happy, you need to keep poking and prodding around at any piece of hardware you come across.
If you’re looking for a comprehensive list of features, that’s a little harder to nail down. Partially because the device has picked up a number of new tricks (such as support for Bluetooth and NFC) thanks to the fact it made better than 8,000% of its original funding goal, but also because it can be expanded with additional hardware and software which obviously won’t get developed until the community gets their hands on the core device.
But even the core functionality, demonstrated in the video after the break, is quite compelling. The Flipper Zero’s CC1101 transceiver chip (anyone else
thinking of the IM-ME
right now?) allows it to record, analyze, and play back RF signals from 300 to 928 MHz, meaning you can instantly take over remote control systems that aren’t using a rolling code for authentication. It can also read and emulate many different RFID cards, record and transmit IR signals, emulate a USB HID device and run programmable payloads, and act as a USB to UART/SPI/I2C adapter. All contained in a sleek and pocket-sized enclosure that looks like a proper cyberpunk hacking gadget.
We’re extremely interested in seeing what the community can do with the Flipper Zero, especially now that the extra windfall has allowed the team to create a formal Developer Program for people who want to help work on the core platform or produce add-on modules. After banking nearly $5 million, this will be the yardstick by which all other crowd sourced hacking gadgets are measured for years to come; let’s hope they make it count.
https://www.youtube.com/watch?v=0T0YIzfigA4 | 22 | 7 | [
{
"comment_id": "6275298",
"author": "Pedant",
"timestamp": "2020-09-03T00:26:54",
"content": "I might be wrong, but it looks like the flipper zero and the flipper one are different products, and this article might mix them up.From what I can tell:The Flipper Zero is a microcontroller-powered arduin... | 1,760,373,368.789186 | ||
https://hackaday.com/2020/09/02/building-an-open-source-thinkpad-battery/ | Building An Open Source ThinkPad Battery | Tom Nardi | [
"ATtiny Hacks",
"laptops hacks"
] | [
"battery pack",
"SMBus",
"T420",
"thinkpad"
] | If you own a laptop that’s got a few years on the clock, you’ve probably contemplated getting a replacement battery for it. Which means you also know how much legitimate OEM packs cost compared to the shady eBay clones. You can often get two or three of the knock-offs for the same price as a single real battery, but they never last as long as the originals. If they even work properly at all.
Which is why [Alexander Parent] decided to take the road less traveled and
scratch built a custom battery for his ThinkPad T420
. By reverse engineering how the battery pack communicated with the computer, he reasoned he would be able to come up with an open source firmware that worked at least as well as what the the third party ones are running. Which from the sounds of it, wasn’t a very high bar. From a more practical standpoint, it also meant he’d be able to create a higher capacity battery pack than what was commercially available should he chose to.
A logic analyzer wired in between one of the third party batteries and a spare T420 motherboard allowed [Alexander] to capture all the SMBus chatter between the two. From there he wrote some Arduino code that would mimic a battery as a proof of concept. He was slowed down a bit by an undocumented CRC check, but in the end he was able to come up with a fairly mature firmware that even allows you to provide a custom vendor name and model number for your pack.
The code was shifted over to an ATtiny85, with a voltage divider wired up to one of the pins so it can read the pack voltage. [Alexander] says his firmware still doesn’t do a great job of reporting the actual battery capacity remaining, but it’s close enough for his purposes. He came up with a simple PCB design to hold the MCU and support components, which eventually he plans on putting inside of a 3D printed case that actually plugs into the back of his T420.
This project is obviously still in a relatively early stage, but we’re very interested to see [Alexander] take it all the way. The
ThinkPad has long been the hacker’s favorite laptop
, and we can think of no machine more worthy of a fully open hardware and software battery pack. | 13 | 5 | [
{
"comment_id": "6275267",
"author": "Moryc",
"timestamp": "2020-09-02T20:55:31",
"content": "Why would anyone use a logic analyzer to reverse-engineer the battery pack, when one needs only to look-up the BMS chip in the battery pack and find the datasheet? Usually the only thing left out of them is... | 1,760,373,368.724316 | ||
https://hackaday.com/2020/09/02/pause-your-tunes-when-it-is-time-to-listen-up/ | Pause Your Tunes When It Is Time ToListen Up! | Brian McEvoy | [
"digital audio hacks",
"The Hackaday Prize"
] | [
"android",
"audio processing",
"dev board",
"embedded C",
"ios",
"microcontroller",
"music control",
"sound detection",
"stm32",
"stm32cubemx",
"text to speech",
"windows mobile"
] | “Sorry. I had music playing. Would you say that again?” If we had a money-unit every time someone tried talking to us while we were wearing headphones, we could afford a super-nice pair. For an Embedded C class, [extremerockets] built
Listen Up!
, a cutoff switch that pauses your music
when someone wants your attention.
The idea was born while sheltering in place with his daughter, who likes loud music, but he does not want to holler to get her attention. Rather than deny her some auditory privacy,
Listen Up!
samples the ambient noise level, listens for a sustained rise in amplitude, like speech, and sends a pause signal to the phone. Someday, there may be an option to route the microphone’s audio into the headphones, but for now there is a text-to-speech module for verbalizing character strings. It might be a bit jarring to hear a call to dinner in the middle of a guitar riff, but we don’t like missing dinner either, so we’re with [extremerockets] on this one.
We don’t really need lots of money to get
fun headphones
, and we are not afraid of
making our own
.
The
Hackaday
Prize2020
is Sponsored by: | 9 | 6 | [
{
"comment_id": "6275205",
"author": "Ragnarok700",
"timestamp": "2020-09-02T18:45:45",
"content": "I like the hack, that’s pretty cool… One question though… why just not send an SMS or whatever preferred form of communication of the person to their cell?",
"parent_id": null,
"depth": 1,
... | 1,760,373,368.830467 | ||
https://hackaday.com/2020/09/02/the-b-sides-curious-uses-of-off-the-shelf-parts/ | The B-Sides: Curious Uses Of Off-the-Shelf Parts | Sonya Vasquez | [
"Engineering",
"Hackaday Columns"
] | [
"cnc",
"engineering",
"McMaster-Carr",
"parts",
"precision"
] | I admit: a few years of prototyping without easy machine shop access really whets my tastebuds for turning metal chips. But all that time spent away from proper machine tools has also pushed me to re-imagine part catalogs, something I see almost every day. Without any precision metalworking tools handy, stock mechanical parts have become my supplement for complexity. And so a former dogma to machine-everything-thyself has been transformed into a hunt for that already-made-part-that-does-it-for-you.
But with part catalogs featuring tens of thousands of purpose-built parts, I started reimagining some of them for other misdeeds. And after a few years spent reinventing use cases for some of these parts, I’m about ready to tell you how to misuse them
properly
. So today I’d like to show you some of my favorite mechanical part
B-sides
, so to speak. These are ordinary parts in unorthodox places–something you surely won’t find in the datasheet! Now let’s have a look.
From Steel Balls and Pins to Kinematic Couplings
To warm things up, let’s start with kinematic couplings. Kinematic couplings are a mechanical design pattern that, when applied to two components, allows those components to connect and disconnect with extreme
repeatability
. This property comes from following
the method of exact-constraint
. By design, the two components are connected together with exactly one constraint per degree of freedom, no more, no less. The result is that, when connected together, coupled parts neither bind nor wiggle; they fit together one and only one way.
Kinematic couplings are often
used in optical instrumentation setups
where mirrors and lenses need to be finely adjusted without, of course, binding or wiggling. Typically these couplings are manufactured from extremely dense materials like hardened steel such that the coupling’s points of contact don’t deform. That may be all well and good for Thorlabs, but we too can make some decent Maxwell couplings from a mishmash of stock and 3D printed parts.
An early kinematic coupling proof of concept.
an assembled subsection of a cnc pen plotter.
The toolchanging pen plotter’s carriage
and a rack full of pen tools.
In this setup, the six points of contact in the coupling are made from hard steel parts like their expensive counterparts, but everything else is 3D printed. Since the points of high stress in this design are covered by dense components, the result is both fairly repeatable while being mostly-3D-printed. In fact, in testing the coupling above, I’ve observed a consistent repeatability just under 25 microns. Sure, that may be more than the sub-micron repeatability of some high end couplings, but for many applications it’s fantastic.
I’ve experimented with setups like the one above with a mix of press-fit dowel pins or shoulder screws combined with threaded steel balls. The dowel pins and shoulder screws are quick finds on McMaster-Carr or Aliexpress, but the threaded balls are actually
3D printer replacement parts
from a Kossel Delta 3D printer. It goes to say that our palate of stock parts need not be limited to component catalogs exclusively but can extend into the ecosystem of RC, 3D Printer, and other hobbyist replacement parts now commoditized by the consumer goods they go into.
Battery Clips Recast for Fixturing
Now let’s redirect our precision locating adventures out of the optics lab and into the wet lab where we find ourselves working with 96-well plates. In an automated setup, these plates will be fixed into a machine deck where an overhead robot will perform liquid transfers on them. Here, plates need to be held tight enough so they don’t move with machine vibration–but not too tight–or they’ll risk spilling when scientists arrive on scene to collect them.
A gentle preload to hold these well plates in a fixed position would be ideal here. Some sort of leaf spring would be nice, but
custom leaf springs are expensive
. So let’s ask: what’s another canonical part offering gentle preload that comes in all shape and sizes? Battery clips of course!
Battery Clips keep plates in place.
The full deck region
of a homebrew sonication station.
Here I opted for Keystone Electronics’ 5205 Battery Contact Spring (
Digikey
) intended for molded plastic. My setup resulted in press-fitting them into three stacked layers of laser cut Delrin without any batteries, but shh–the contacts will never know the difference! Since battery contacts are designed to be compressed for long periods of time without fatiguing, the contacts shouldn’t weaken from plates in the fixture overnight. (No word on how many cycles they’re rated for, but for a budget prototype these will do just fine.)
Mini Spring Anchors on a Budget
Now let’s transition to working with extension springs. These springs often arrive with loops on each end to make them easier to attach into their target application. But when it comes to hooking them into 3D printed or laser-cut plastic parts, attaching springs to small integrated plastic features risks them tearing out of the part.
One solution is a stock part called a
spring hook
or
spring anchor
. While large spring anchors tend to be prolific, small ones aren’t. Alas, in my original hunt for spring anchors, I could only turn up
one Misumi part
at the M3 scale I was looking for. And at $5 apiece, they’re exorbitantly more expensive than other stock parts in my fastener bucket. As for simply opting for a screw in this case, it turns out that they make inconvenient spring anchors for two reasons: (1) the head gets in the way of installing the spring and (2) they only work well if the extension spring can be installed perpendicular to the screw. Surely, I thought, there must be a cheaper solution in this pile of part catalogs.
Keystone PN: 4000 yields to the Pliers!
An extension spring looped between two terminal lugs
Jubilee’s Bed Springs. Image Credit: [Cindy Feng]!
Keystone PN: 7328 also yields to the pliers!
PN: 7328 post bending operation
Springs installed in a Series-Elastic Actuator
And there was! The answer arrived in the form of
solder terminal lugs
. These are normally intended to be soldered into a wire at one end and screwed into an electrical terminal at the other. And at about 20 cents apiece, they’re also quite cheap. Best of all, since they’re made from brass, they can be formed with pliers into a shape that’s convenient for retaining the spring at a particular orientation. I’ve used both Keystone Electronics’ 7328 (
Digikey
) and 4000 (
Digikey
) parts to hole small extension springs in compact odd configurations each of which was gently “pliered” into a convenient orientation first.
Vented Screws reimagined as Cable Tensioners
These next parts hearken back to my
3 part mini-series building up two-stage animatronic tentacle mechanisms
. These systems are driven with a pair of hand controllers that tug on a set of mechanical control cables. Just like a bicycle, having these cables adjustable for proper tension is key to getting them to work smoothly without any perceivable “slop” or
backlash
. Bicycles rely on a screw based mechanism that lets the user fine tune the tension by effectively changing the length of the cable housing. Could I use a stock part to do the same thing?
Yes! It turns out I’d been ogling McMaster-Carr’s
vented screws
category for a couple years hoping I’d someday have an excuse to buy them, and the time had finally arrived. Vented screws are essentially screws with a small hole drilled down the center. Were I some process engineer specializing in pressure vessels, I’d probably tell you how these screws, combined with an o-ring, form a useful part of a servoed pressure control system. But I can’t. What I
can
tell you is that threading the mechanical control cable through these vented screws creates an exceptional cable tension adjustment point.
This screw has a hole down the middle!
Twisting the screw increases cable tension!
By installing one vented screw per cable into the into the laser-cut controller, the entire system can be fine tuned for a high-fidelity puppeteering performance as compelling as the good ol’ 1979 Alien chest-burster scene.
The Standoff Sandwich
Standoffs are metal posts threaded at both ends. They might be the electronic engineer’s go-to for mounting circuit boards, but I’d claim they’re a great way to mounting m
any
mostly-flat components–not just circuit boards–in a rapid prototyping or hobbyist use case. I call this technique the
standoff sandwich
, and I’ve
mentioned it once before
. Here standoffs combine with laser-cut elements to build up a 3D structure. Since they’re available in a range of lengths, we sidestep the need to machine parts to length by simply buying the part at the correct length. We need not limit ourselves to one layer either. Double and triple-decker standoff sandwiches are all fair game too. And at about 50 cents apiece, the overall costs for a significant portion of your structure can be fairly cheap too.
Odds and Ends on my 60W Laser Cutter
Details on an old Laser-Cut CoreXY
Gamecube-Bot 2
Gamecube-Bot 3 Prototype
Motorized Tentacle Prototype
… uses standoff-sandwiches to the extreme
These days, I find them useful for small scale robotics applications when mixed with 3D printed or laser cut parts.
A Vocabulary of Parts
It’s been two years since I tore down my garage “machine shop” and took the leap back to school for one last mission. With my best tools in the deep sleep of storage, I thought I’d be giving up feeding
my part-hungry soul
with a steady stream of machining projects.
But something else happened. Far away from the tools, I found part catalogs. These field guides to the “pickings” of “Part Land” became my saving grace, a new way to design widgets–without actually machining anything! And with some creative use-case reimagining, I discovered that the capabilities of this part
vocabulary
go far beyond what the books say. With today’s examples, I hope you start to see that too. So the next time you need a little machine shop “glue logic,” I hope you challenge yourself to go beyond what you can make and include the span of what you can find too. | 44 | 19 | [
{
"comment_id": "6275163",
"author": "modmanpaul",
"timestamp": "2020-09-02T17:09:01",
"content": "this is an awesome post idea. I hope it becomes a very regular feature",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6275169",
"author": "Pinhead",
... | 1,760,373,368.966026 | ||
https://hackaday.com/2020/09/02/hacker-driven-to-build-r-c-forza-controller/ | Hacker Driven To Build R/C Forza Controller | Kristina Panos | [
"Microcontrollers",
"Misc Hacks",
"Xbox Hacks"
] | [
"arduino",
"arduino pro micro",
"carbon fiber wrapping",
"dongle",
"forza",
"pwm",
"R/C car"
] | Generic video game console controllers have certainly gotten better and more ergonomic since the hard corners of the Atari joystick. As beautiful and engrossing as games have become, the controller is still the least engaging aspect.
Why race your sweet fleet of whips with an ordinary controller when you could pretend they’re all R/C cars?
[Dave] found an affordable 4-channel R/C controller in the Bezos Barn and did just that. It took some modifications to make it work, like making a daughter board to turn the thumb grip input from a toggle button to a momentary and figuring out what to do with the three-way slider switch, but it looks like a blast to use.
The controller comes in a 6-channel version with two pots on the top. Both versions have the same enclosure and PCB, so [Dave] already had the placement molded out for him when he decided to install a pair of momentary buttons up there. These change roles based on the three-way slider position, which switches between race mode, menu mode, and extras mode.
We love the way [Dave] turned the original receiver into a USB dongle that emulates an Xbox 360 controller — he made a DIY Arduino Pro Micro with a male USB-A, stripped down the receiver board, and wired them together. There’s an entire separate blog post about that, and
everything else you’d need to make your own R/C controller is on GitHub
. Check out the demo and overview of the controls after the break.
[Dave] is no stranger to making game controllers — we featured his
DJ Hero controller modified to play Spin Rhythm XD a few months ago
.
Via
r/duino | 6 | 5 | [
{
"comment_id": "6275142",
"author": "hg",
"timestamp": "2020-09-02T16:16:11",
"content": "Nice implementation. This is a great idea to add some life into racing games when they start to get boring. Well done man.",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": ... | 1,760,373,368.876707 | ||
https://hackaday.com/2020/09/02/an-up-close-look-at-the-first-martian-helicopter/ | An Up-Close Look At The First Martian Helicopter | Dan Maloney | [
"drone hacks",
"Engineering",
"Featured",
"Original Art",
"Slider"
] | [
"helicopter",
"Ingenuity",
"jpl",
"mars",
"Mars 2020",
"mars helicopter",
"nasa"
] | The news was
recently abuzz
with stories of how the Mars 2020 mission, which launched from Cape Canaveral at the end of July, had done something that no other spacecraft had done before: it had successfully charged the batteries aboard a tiny helicopter that is hitching a ride in the belly of the Mars 2020 rover, Perseverance.
Although the helicopter, aptly named Ingenuity, is only a technology demonstrator, and flight operations will occupy but a small fraction of the time Mars 2020 is devoting to its science missions, it has still understandably captured the popular imagination. This will be humanity’s first attempt at controlled, powered flight on another planet, after all, and that alone is enough to spur intense interest in what amounts to a side-project for NASA. So here’s a closer look at Ingenuity, and what it takes to build a helicopter that will explore another world.
Designed for Mars
Despite coverage in the popular press about how NASA is sending a drone to Mars, there’s practically no resemblance between Ingenuity and any conventional terrestrial multicopter. It turns out that when you design a helicopter to operate in a place where the air is as thin as it is at 115,000 feet (35 km) on Earth and with a third its gravitational pull, you end up with a unique and unusual machine.
Artist’s impression of Ingenuity post-deployment. Source:
NASA/JPL
The most striking difference between Ingenuity and a more traditional multicopter is the choice to make it a dual-rotor design. There would have been no way to go with a quadcopter design, mostly due to the size of the rotors but also because it would have vastly complicated stowage of the helicopter.
According to
a paywalled paper
by the engineers who designed Ingenuity, NASA was also worried about the phenomenon of blade flapping, which is caused by flexing of the rotor blades above and below the plane of rotation. Without Earth’s thick atmosphere to damp blade flapping, a traditional rotor design would likely tear itself to pieces on Mars. So the blades for Ingenuity were designed to be extremely stiff while at the same time being thin, lightweight, and very broad across the blade root, to provide the extra lift needed in the thin Martian atmosphere. The blades are built from a composite of carbon fiber skins over a molded foam core, and each of the two coaxial rotors is just over 1.2 meters in diameter.
Another way in which Ingenuity differs from terrestrial multicopters is in the flight control systems. Where most quads only have fixed-pitch rotor blades and use differential motor speed to achieve pitch, yaw, and roll control, Ingenuity uses a pair of swashplates to control each rotor’s collective and cyclic pitch. Each titanium swashplate is controlled by a trio of tiny servos anchored to the rotor mast, and is connected to the rotor using connecting rods machined from polyetheretherketone (PEEK) plastic.
Unsurprisingly, the motors for Ingenuity are pretty special too. Like most terrestrial multicopters, Ingenuity’s two motors are of the brushless DC design, but the similarities stop there. The 46-pole stator was hand-wound using copper wire with a rectangular cross-section, to allow for better packing than would be possible with round copper wire. The high coil count and the exotic lightweight materials used for the housing make the motors very efficient, very light, and very compact. They’re also hard to spot in the photograph below; one is barely peeking out from between the top rotor and the solar panel, while the other is nestled between the bottom rotor and the swashplate for the upper rotor.
Detail of Ingenuity’s swashplates and rotor hubs. Note that the PEEK linkages from the servos to the swashplates seem to have not been installed yet. Source:
NASA/JPL
Deployment
As configured for flight, Ingenuity is just as gangly and unwieldy as every other helicopter. Finding a way to stow any helicopter in a compact, shippable package is a complex task, and only more so when it needs to survive a rocket launch, a six-month interplanetary journey, and a high-energy autonomous landing on Mars.
Ingenuity safely tucked into the belly of Perseverance (bottom center, click to enlarge). Source:
NASA/JPL
Ingenuity’s design makes at least the job of stowing the craft straightforward, thanks to its thin profile when the rotor blades are aligned with each other. The landing legs are another thing, though. The hinges for the four legs need to allow the legs to bend up toward the rotors to make the package as small as possible, while still providing shock absorption for landings. To accomplish both goals, each leg is attached to the body by a deployment hinge, which snaps the leg down to their deployed position under spring pressure. Just after the deployment hinge is a titanium and aluminum flexure, a compliant mechanism that absorbs the shock of up to 2 meters per second landings.
Deploying Ingenuity to the Martian surface will be a complex, highly orchestrated process. The helicopter is stowed in the underbelly of Perseverance, behind the bay holding
the Adaptive Caching Assembly
. Despite the presence of a robot arm in the ACA bay, Ingenuity will not be plucked from storage and placed gingerly on the surface. Rather, as the video below (source:
NASA/JPL
) demonstrates, after a debris shield is jettisoned and the rover moves away to a clear zone, the helicopter will swing down from its horizontal storage position to a vertical orientation. The legs will be released to spring into position, and the helicopter will be dropped a few inches to the Martian surface. It’s an operation that will no doubt take days to complete, as each stage of deployment will be preceded and followed by multiple systems checks and surveys of the area with the many cameras sprouting from the rover and the helicopter itself.
https://hackaday.com/wp-content/uploads/2020/09/Ingenuity-Deployment_cropped.mp4
Surface Operations
Once free from the plutonium-warmed belly of Perseverance, Ingenuity will have to deal with the extreme cold of Martian nights all by itself. The electronics needed to run the helicopter, including the already-charged batteries, the flight controller, and the cameras and other sensors needed for the look-down navigation system and altimeters, are all housed within a thermal management enclosure called the Helicopter Warm Electronics Box, or HWEB. This box dangles between the helicopter landing legs and uses a combination of thin-film heaters and a layer of polyamide insulation to both absorb as much solar thermal energy as possible while reducing heat loss from the inside of the HWEB to the Martian atmosphere.
Close up of Ingenuity’s central core, including landing gear flexures, lower rotor swashplate servos, and HWEB. Click to enlarge. Source:
NASA/JPL
Having an autonomous helicopter at your disposal might seem like a dream come true for mission planners, allowing them to quickly get eyes on some interesting feature to see if it’s worth slowing driving the rover over for a closer examination. And indeed, that’s something that NASA very much has in mind for future missions. But Ingenuity has far more modest goals, mainly as a proof-of-concept of non-terrestrial flight.
After proving that it can survive the ride to Mars, descent and landing, and being successfully deployed to the surface, Ingenuity is scheduled for only a few short flights. None of the fully autonomous test flights will last no more than 90 seconds, and the helicopter will stay within 50 meters of Perseverance and never get more than 5 meters above the surface.
Assuming Ingenuity is able to get off the surface and land safely again, a total of up to four additional flights will take place. But once the test period is over, Perseverance will move on, hopefully leaving the spidery helicopter upright on the Martian surface, having fulfilled its mission of proving that aircraft can operate on other worlds. | 49 | 14 | [
{
"comment_id": "6275118",
"author": "jake",
"timestamp": "2020-09-02T14:29:12",
"content": "I lol’d at the lead image. Good artist!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6275124",
"author": "paywalls are bad",
"timestamp": "2020-09-02T14:47:3... | 1,760,373,369.171521 | ||
https://hackaday.com/2020/09/02/staged-train-wrecks-an-idea-that-ran-out-of-steam/ | Staged Train Wrecks: An Idea That Ran Out Of Steam | Kristina Panos | [
"Misc Hacks",
"Transportation Hacks"
] | [
"demolition derby",
"steam engine",
"steam locomotive",
"the Crash at Crush",
"train",
"trainwreck"
] | Before there were demolition derbies, there were train totalings
. That’s right, somebody had the idea to take a couple of worn-out train engines that were ready for the scrap heap, point them at each other, and drive them full steam ahead. And their boss said capital idea, let’s do it. This was the late 1890s.
Maybe it wasn’t the safest way to spend an evening, but a staged train wreck was surely an awesome spectacle to behold. Imagine being one of the brave engineers who had no choice but to get the train going as fast as possible and then jump out at the last second. A demolition derby seems like child’s play by comparison.
The largest and most widely-publicized wreck was put on by a man named William George Crush who was trying to find new ways to promote the Missouri-Kansas-Texas passenger railway. Once he got the okay, Crush found a large field surrounded by three hills that made for excellent viewing. He stood up a temporary town complete with a circus tent restaurant, a wooden jail cell, and 200 rent-a-constables.
On September 15th, 1896, forty thousand people gathered to watch two trains collide along a section of purpose-built track. They hit each other going 50 mph (80 km/h) and both engines exploded, sending hot iron projectiles every which way. Several people were injured, a few died, and a hired photographer lost an eye to shrapnel. Train totalings nevertheless continued until the Great Depression of the 1930s, when the practice was discarded as wasteful.
Thanks for the tip, [Martin]! | 35 | 13 | [
{
"comment_id": "6275067",
"author": "fdufnews",
"timestamp": "2020-09-02T11:29:01",
"content": "We knew how to have fun in those days",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6275481",
"author": "qwert",
"timestamp": "2020-09-03T16:26:... | 1,760,373,369.079275 | ||
https://hackaday.com/2020/09/02/wiiboy-color-is-exactly-what-it-sounds-like/ | WiiBoy Color Is Exactly What It Sounds Like | Lewin Day | [
"Nintendo Hacks",
"Nintendo Wii Hacks"
] | [
"game boy",
"handheld gaming",
"nintendo",
"nintendo wii",
"wii",
"wii handheld",
"wii portable"
] | Anyone can go out and buy a handheld console, and if you want to be the cool kid on the school bus, you can always ask your parents to take you out to get one. But if you want real street cred that lasts through your adult years, you’ve gotta put something together yourself.
[GingerOfMods] has done just that with the Wiiboy Color.
Yes, it’s another home-console-turned-portable, and it’s perfomed with exquisite execution. The Wii motherboard is cut and sliced to the absolute bare minimum, as the aim was to build the entire system to the rough form factor of the original Game Boy Color. Custom PCBs were then used to link the chopped ‘board to peripherals, such as the USB drive used to load games and the circuitry from a Gamecube controller. The screen is a beautiful looking 3.5″ IPS LCD, running at 480p and originally intended for use as an automotive backup camera. Battery life is around 2-3 hours, with a USB-C port included for easy charging.
More details are included on the forum build log.
It’s a tidy build, and the 3D printed case, Switch joysticks and DS Lite buttons give it a near-production quality finish. [GingerOfMods] intends to build more for commissions, though expect a hefty price tag given the labor and custom work involved. We’ve seen other portable Wiis before too,
like this tightly-packed Kapton-heavy build.
Video after the break.
[Thanks to LG Dirk for the tip!] | 16 | 8 | [
{
"comment_id": "6275058",
"author": "Alfie",
"timestamp": "2020-09-02T10:54:32",
"content": "I want one. Dont make me make it.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6275076",
"author": "qwerty",
"timestamp": "2020-09-02T11:45:17",
... | 1,760,373,369.015212 | ||
https://hackaday.com/2020/09/01/tinysa-is-a-49-spectrum-analyzer/ | TinySA Is A $49 Spectrum Analyzer | Al Williams | [
"Tool Hacks"
] | [
"nanovna",
"spectrum analyzer",
"tinysa"
] | The NanoVNA made network analyzers cheap enough for almost everyone. Now you can get a $49 spectrum analyzer to go with it. Is it worth it?
Watch [IMSAI Guy]’s video
after the break for his opinion. From the
tinySA.org
website:
Spectrum Analyzer with two inputs, high-quality MF/HF/VHF input for 0.1MHZ-350MHz, lesser quality UHF input for 240MHz-960MHz.
Switchable resolution bandpass filters for both ranges between 2.6kHz and 640kHz
Color display showing 290 scan points covering up to the full low or high-frequency range.
Input Step attenuator from 0dB to 31dB for the MF/HF/VHF input.
When not used as Spectrum Analyzer it can be used as Signal Generator, MF/HF/VHF sinus output between 0.1MHZ-350MHz, UHF square wave output between 240MHz-960MHz.
A built-in calibration signal generator that is used for automatic self-test and low input calibration.
Connected to a PC via USB it becomes a PC controlled Spectrum Analyzer
Rechargeable battery allowing a minimum of at least 2 hours portable use
A lot of cheap scopes and PC-based scopes can do spectrum analysis, too, of course, so this isn’t as exotic as a VNA. But at this price, having a dedicated instrument might be worth it to you, especially if you don’t care about frequencies below 100 kHz.
There are some limitations, of course, but the price is right. [IMSAI Guy] shows a few oddities that he didn’t like, but overall, it seemed like a good value. If you have a modern scope it may already do this function, or you might be able to do a
software solution
. If you only need audio frequencies and you want novelty, try some
ping pong balls | 48 | 17 | [
{
"comment_id": "6275017",
"author": "jpa",
"timestamp": "2020-09-02T06:50:03",
"content": "NanoVNA V2 is similar in price and frequency range is much wider, but I’m not sure how it compares in features and performance:https://www.tindie.com/products/hcxqsgroup/nanovna-v2/",
"parent_id": null,
... | 1,760,373,369.318075 | ||
https://hackaday.com/2020/09/01/retrocomputing-spray-paints-amiga-beige-commodore-and-atari-grey/ | Retrocomputing Spray Paints: Amiga Beige, Commodore, And ATARI Grey | Donald Papp | [
"Retrocomputing"
] | [
"amiga",
"atari",
"c-64",
"commodore",
"custom",
"retrocomputing",
"spray paint",
"vintage"
] | [retrohax] has provided vintage computer guidance for years, and part of that guidance is this: sometimes using paint as part of restoration is simply unavoidable. But the days of tediously color-matching to vintage hardware are gone, thanks to [retrohax] offering custom-mixed spray paints in
Amiga 500 Beige
,
C-64 Beige
, and
ATARI ST/SE Grey
. (At the moment only delivery within Poland is available due to shipping restrictions, but [retrohax] is working on a better solution.)
As a companion to making these vintage colors available, there is also
a short how-to guide on how to properly prep and spray paint a computer case for best results
that talks a little about the challenges in color matching to vintage hardware, and how getting custom paints mixed makes life much easier. Hackers may value making do with whatever is available, but we can also appreciate the value of having exactly the right material or tool for the job.
It’s not every day we see someone mixing custom spray paint colors, but off the shelf options don’t always cut it. Another example of getting specialty materials made from the ground up is
custom plywood specifically designed for laser-cutting puzzles
, something done because the troubles that came with off-the-shelf options were just not worth the hassle. | 19 | 15 | [
{
"comment_id": "6274988",
"author": "Robert W Pope",
"timestamp": "2020-09-02T02:27:13",
"content": "Only in Poland. Gee thanks/",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6275011",
"author": "Matt",
"timestamp": "2020-09-02T05:39:50",
... | 1,760,373,369.228958 | ||
https://hackaday.com/2020/09/01/perfect-photographs-for-pcb-reverse-engineering/ | Perfect Photographs For PCB Reverse Engineering | Jenny List | [
"hardware"
] | [
"pcb",
"pcb photography",
"phototgraphy"
] | There’s an unexpected part of hacking that is very difficult to get right, namely photographing printed circuit boards. Everything seems to catch the light, making for a complex dance of manipulating light sources and camera angles. We were thus captured by [Roman Valls]’
budget rig for taking PCB photos
that makes ingenious use of roadside trash to achieve a result.
It was inspired by
a video featuring a much more accomplished rig
, which he set out to emulate for much less outlay. Instead of an expensive lens, he’s using a Nikon camera with its kit lens. And instead of a tripod there’a a scrap drawer salvaged from the roadside and modified to become a camera holder. Lighting is diffused by baking paper, and the result is a rig that can photograph PCBs with neutral lighting and without annoying highlights.
We especially like work that takes junk and makes something useful from it, and though our purpose isn’t in reverse engineering it’s impressive to see how well the technique reveals the traces. We’ll definitely be experimenting with some of the techniques herein, and those lighting tips might also work with
the Hackaday ear camera microscope
. | 19 | 6 | [
{
"comment_id": "6274747",
"author": "e",
"timestamp": "2020-09-01T09:39:35",
"content": "Once you have the photo, you can place the resulting images on a layout for reverse engineering quite easily in the open source PCB layout editor pcb-rndhttp://repo.hu/cgi-bin/pool.cgi?cmd=show&node=background_... | 1,760,373,369.533114 | ||
https://hackaday.com/2020/08/31/the-hurricanes-are-coming/ | The Hurricanes Are Coming | Bryan Cockfield | [
"Raspberry Pi"
] | [
"alert",
"emergency",
"hurricane",
"led matrix",
"python",
"raspberry pi",
"weather"
] | It’s hurricane season in the northern hemisphere right now, and plenty of news and weather organizations remain dedicated to alerting people if a storm is about to impact their area. There’s no shortage of ways to receive this information, either. We all have our favorite weather app or forecasting site, and there are emergency alerts to cell phones, TV, and radio stations as well. If none of that suits you, though, you can also
roll out your own weather alert readerboard
.
[Damaged Dolphin] built a weather alert readerboard using a Raspberry Pi and a 64×128 LED matrix. The Raspberry Pi runs Raspbian and uses a HAT from Adafruit, and once connected to the internet pulls down weather information for a specific area using custom python code. From there it can display any emergency weather alerts instantly on the readerboard screen including alerts for hurricanes. It does rely on data from the National Weather Service though, so if that is not available in your area some modifications will need to be made to the code.
While he notes that you probably shouldn’t rely on his non-professional python code exclusively when getting weather information, it would still be a good way of retrieving information about weather events without having to refresh a browser all the time. Once the storms have passed though,
be sure you’re prepared for the days following
.
Thanks to [b00tfa|l] for the tip!
https://www.youtube.com/watch?v=rZrlYOqqqbk | 8 | 3 | [
{
"comment_id": "6274736",
"author": "Rob T",
"timestamp": "2020-09-01T07:29:06",
"content": "Not really the whole Northern Hemisphere. By the time they get to the UK they are just damp squibs, not that it stops us fretting about “terrifying” gusts of 70mph.",
"parent_id": null,
"depth": 1,
... | 1,760,373,369.57383 | ||
https://hackaday.com/2020/08/31/an-analog-ic-design-book-draft/ | An Analog IC Design Book Draft | Al Williams | [
"hardware",
"Misc Hacks"
] | [
"analog",
"analog design",
"ASIC",
"book",
"free book",
"linkedin"
] | [Jean-Francois Debroux] spent 35 years designing analog ASICs. He’s started a book and while it isn’t finished — indeed he says it may never be — the
180 pages he posted on LinkedIn
are a pretty good read.
The 46 sections are well organized, although some are placeholders. There are sections on design flow and the technical aspects of design. Examples range from a square root circuit to a sigma-delta modulator, although some of them are not complete yet. There are also sections on math, physics, common electronics, materials, and tools.
The text is decidedly practical. For example, there’s a succinct summary of what a MOSFET channel width and length do to parameters such as capacitance, noise, and saturated resistance.
If you prefer a PDF copy, here’s a tip. When viewing the document, click on the full-screen button. Then at the top, you’ll see a download button. The link there looks as though it isn’t a static link, so you’ll need to visit the post yourself to do the download.
It is a lot of work to put a book together and even though this isn’t complete, it is a great start and already useful. If you want some more
book recommendations
, check out ours. We never fail to recommend
The Art of Electronics
, too. | 21 | 11 | [
{
"comment_id": "6274704",
"author": "Mike Massen",
"timestamp": "2020-09-01T03:13:04",
"content": "Nice post, reminiscent of the National Semiconductor Linear Applications handbook 1980 which had some useful design notes particularly for me in respect of instrumentation :-)",
"parent_id": null... | 1,760,373,369.3832 | ||
https://hackaday.com/2020/08/31/a-3d-printed-paint-mixer/ | A 3D Printed Paint Mixer | Danie Conradie | [
"3d Printer hacks",
"Tool Hacks"
] | [
"3d printed",
"mark rhodes",
"mixer",
"paint",
"turbula"
] | To get the perfect mix for your paint, you need a good shake that is as random as possible. [Mark Rhodes] wanted to automate the process of mixing paint, so he built a
3D printed shaker
to thoroughly shake small paint bottles. Using only a single motor, it shakes the bottle along three axes of rotation and one axis of translation.
A cylindrical container is attached to a U-shaped bracket on each end, which in turn is attached to a rotating shaft. Only one of these shafts are powered, the other is effectively an idler. When turned on, it rotates the cylinder partially around the pitch and yaw axis, 360 degrees around the roll axis, and reciprocates it back and forth. The design appears to be based on an industrial mixer known as a “
Turbula
“. Another interesting feature is how it holds the paint bottle in the cylinder. Several bands are stretched along the inside of the cylinder, and by rotating one of the rings at the end, it creates an hourglass-shaped web that can tightly hold the paint bottle.
The mechanism is mounted on a 3d printed frame that can be quickly clamped to a table. The Twitter post embedded below is a preview for a video [Mark] is working for his
Youtube channel
, along with which he will also release the 3D files.
Mixing machines come in all shapes and sizes, and we’ve seen a number of 3D printed versions, including a
static mixer
and a
magnetic stirrer
.
So I have been working on a little something to help me mix my paints. It is completely and utterly over engineered for the problem, and that is why it reminds me of the bottle opener that
@donttrythis
and
@Laura_kampf
made 🤣. It does look cool though!
pic.twitter.com/2EatMGfC5j
— Mark Rhodes (@mrhodes)
August 25, 2020 | 10 | 9 | [
{
"comment_id": "6274695",
"author": "Comedicles",
"timestamp": "2020-09-01T02:19:07",
"content": "“To get the perfect mix for your paint, you need a good shake that is as random as possible.” or something really well organized that mixes it half and half 16 times (for a paint can 20cm tall – add on... | 1,760,373,369.624927 | ||
https://hackaday.com/2020/08/31/pocket-tv-now-shows-the-inspection-channel-24-7/ | Pocket TV Now Shows The Inspection Channel 24/7 | Kristina Panos | [
"how-to",
"Misc Hacks",
"Tool Hacks"
] | [
"analog tv",
"antenna",
"camera",
"inspection camera",
"pocket TV"
] | Those little pocket TVs were quite the cool gadget back in the ’80s and ’90s, but today they’re pretty much useless at least for their intended purpose of watching analog television. (If someone is out there making tiny digital-to-analog converter boxes for these things, please let us know.)
Now that analog pocket TVs are obsolete, they’re finally affordable enough for hacking into a useful tool like an inspection camera
. [technichenews] found a nice Casio TV and a suitable analog pinhole camera that also does IR. Since the camera has RCA plugs and the TV’s video input is some long-gone proprietary 3.5mm cable, [technichenews] made a new video-only cable by soldering the yellow RCA wires up to the cable from an old pair of headphones. Power for the camera comes from a universal wall wart set to 12V.
Our favorite part of this project is the way that [technichenews] leveraged what is arguably the most useless part of the TV — the antenna — into the star. Their plan is to use the camera to peer into small engines, so by mounting it on the end of the antenna, it will become a telescoping, ball-jointed, all-seeing eye. You can inspect the build video after the break.
Need a faster, easier way to take a closer look without breaking the bank?
We hear those slim earwax-inspection cameras are pretty good
.
https://www.youtube.com/watch?v=G6qDQXUxU0k
Via
Instructables | 9 | 5 | [
{
"comment_id": "6274638",
"author": "NiHaoMike",
"timestamp": "2020-08-31T22:24:55",
"content": "“If someone is out there making tiny digital-to-analog converter boxes for these things, please let us know.”That’s called a Raspberry Pi Zero W.That said, unless you have a really nice portable TV, tho... | 1,760,373,369.701959 | ||
https://hackaday.com/2020/08/31/oparp-telepresence-robot/ | OPARP Telepresence Robot | Brian McEvoy | [
"Robots Hacks",
"The Hackaday Prize"
] | [
"2020 Hackaday Prize",
"facial recognition",
"follower",
"mobile",
"Mycroft",
"object detection",
"Personal Assistant",
"robot",
"telepresence",
"telepresence robot",
"tensorflow"
] | [Erik Knutsson] is stuck inside with a bunch of robot parts, and we know what lies down that path. His
Open Personal Assistant Robotic Platform
aims to help out around the house with things like filling pet food bowls, but for now, he is taking one step at a time and working out the bugs before adding new features. Wise.
The build started with a narrow base, an underpowered RasPi, and a quiet speaker, but those were upgraded in turn. Right now, it is a personal assistant on wheels. Alexa was the first contender, but Mycroft is in the spotlight because it has more versatility. At first, the mobility was a humble web server with a D-pad, but now it leverages a distance sensor and vision, and can even follow you with a voice command.
The screen up top gives it a personable look, but it is slated to become a display for everything you’d want to see on your robot assistant, like weather, recipes, or a video chat that can walk around with you. [Erik] would like to make something that assists the elderly who might need help with chores and help connect people who are stuck inside like him.
Expressive robots
have long since captured our attention and we’re nuts for
privacy-centric personal assistants
.
The
Hackaday
Prize2020
is Sponsored by: | 0 | 0 | [] | 1,760,373,369.661864 | ||
https://hackaday.com/2020/08/31/start-me-up-what-has-the-windows-95-desktop-given-us-25-years-later/ | Start Me Up: What Has The Windows 95 Desktop Given Us 25 Years Later? | Jenny List | [
"Hackaday Columns",
"History",
"Retrocomputing"
] | [
"gui",
"history",
"microsoft",
"retrocomputing",
"windows 95"
] | We’ve had something of an anniversary of late, and it’s one that will no doubt elicit a variety of reactions from our community. It’s now 25 years ago that Windows 95 was launched, the operating system that gave the majority of 1990s PC users their first taste of a desktop-based GUI and a 32-bit operating system.
To the strains of the Rolling Stones’
Start me up
, Microsoft execs including Bill Gates himself
jubilantly danced on stage
at the launch of what was probably to become the company’s defining product, perhaps oblivious to the line “
You make a grown man cry
” which maybe unwittingly strayed close to the user experience when faced with some of the software’s shortcomings.
Its security may seem laughable by the standards of today and the uneasy marriage of 16-bit DOS underpinning a 32-bit Windows operating system was clunky even in its heyday, but perhaps now is the best time to evaluate it unclouded by technical prejudice. What can we see of Windows 95 in the operating systems we use today, and thus from that can we ask the question: What did Windows 95 get
right
?
For Most People, This Was Where It All Started
A test of the legacy of Windows 95’s desktop comes in how intuitive it still is for users of a 2020-era GUI OS.
Windows 95 was by no means the first operating system to use a desktop based GUI. While earlier Windows GUIs had been more akin to graphical launchers there had been a succession of other GUI-based computers since their Xerox PARC ancestor, so Macintosh and Amiga owners among others could have been forgiven for wondering why it took Redmond so long to catch up. But for all the clamour from the 68k-based fans, the indulgent smiles from X window users on UNIX workstations in industry and universities, and the as yet unfulfilled desktop fantasies of 1995’s hardy band of GNU/Linux users, the fact remains that for the majority of the world’s desktop computer users back then it would be the Microsoft Sound that heralded their first experience of a modern GUI operating system.
We’re lucky here in 2020, to have such computing power at our fingertips that we can run in-browser simulations or even outright emulations running real code of most of the 1990s desktops.
Windows 95
can be directly compared with
its predecessor
, and then with its contemporaries such as
Macintosh System 7
and
Amiga Workbench 3.1
. Few people would have had the necessary four machines side-by-side to do this back then, so paging between tabs their differences and relative shortcomings become rapidly obvious. In particular the menu and windowing systems of the Mac and Amiga desktops which seemed so advanced when we had them in front of us start to feel cumbersome and long-winded in a way the Windows 95 interface for all its mid-90s Microsoft aesthetic, just doesn’t.
Using Amiga Workbench again after 25 years provides an instant reminder that an essential add-on to the Workbench disk back in the day was a little utility that gave window focus to mouse position, brought right-click menus up at the mouse pointer position, and brought focused windows to the front. Good GUIs don’t need to have their shortcomings fixed with a utility to stop them being annoying, they — to borrow a phrase from Apple themselves —
just work
. Right-click context menus at the mouse pointer position, the Start menu bringing access to everything into one place, and the taskbar providing an easy overview of multitasking, they were none of them earth-shattering, but together they set the Windows GUI as the one that became a natural environment for users.
Finding the Very Long Shadow of ’95 today
If you miss ’95,
ReactOS
is probably the closest you can get here in 2020.
Returning to the present and Windows 10, the spiritual if not codebase descendant of Windows 95, has a Start menu and a task bar that will be visibly familiar to a user from 25 years before. They were so popular with users that when Windows 8 attempted to remove them there was something of a revolt, and Microsoft returned them to later versions. The same features appear in plenty of desktop environments in other operating systems including GNU/Linux distributions, indeed it can be found on my laptop running an up-to-date Linux Mint. Arguments will probably proceed at length whether it or the dock-style interface found on NeXT, MacOS, and plenty of other GNU/Linux distros are better, but this legacy of Windows 95 has proved popular enough that it is likely to remain with us for the foreseeable future.
It’s odd, sitting down for this article at a Windows 95 desktop for the first time in over two decades. It’s so familiar that despite my having not possessed a Windows desktop for around a decade I could dive straight into it without the missteps that I had when revisiting Amiga Workbench. It’s almost a shock then to realize that it’s now a retrocomputing platform, and there’s little in my day-to-day work that I could still do on a Windows 95 machine. Perhaps it’s best to put it down before I’m reminded about Blue Screens Of Death, about driver incompatibilities, or Plug and Pray, and instead look at its echoes in my modern desktop. Maybe it did get one or two things right after all.
Header image: Erkaha /
CC BY-SA 4.0 | 103 | 34 | [
{
"comment_id": "6274557",
"author": "Jerry",
"timestamp": "2020-08-31T17:26:44",
"content": "Fond memories of my public “Beta” copy of Windows 95.Microsoft shipped a full set of floppies, AND a CD to install and test.Checking the specs, I was forced to purchase an extra computer so the testing coul... | 1,760,373,369.889875 | ||
https://hackaday.com/2020/09/01/antique-oscilloscope-gets-new-home-and-purpose/ | Antique Oscilloscope Gets New Home And Purpose | Bryan Cockfield | [
"clock hacks"
] | [
"case",
"classic",
"clock",
"crt",
"dutchtronix",
"heathkit",
"IO-102",
"oscilloscope",
"sparkfun",
"vintage"
] | As the pace of technology charges blindly forward, a lot of older tools or products get left in the dust, forgotten to most but those left with them. This doesn’t mean they’re useless, though. In fact, old technology that continues to survive in the present tends to be more robust and sturdy than most modern, cheap replacements. While this might be survivorship bias, this is certainly true in particular of oscilloscopes. Rugged CRTs in large metal housings with discrete through-hole components in simple layouts made them reliable, but they’re heavy, bulky, and lack features of modern instruments. With some modifications, though,
you can give them a new home and keep their vintage aesthetic
.
[BuildComics] had just such an oscilloscope on hand and set out to make it into something useful but aesthetically pleasing as well. With a small circuit board,
formerly available as a kit from Sparkfun/Dutchtronix
but now only available if you can build them yourself, the cathode ray tube can be modified to output not waveforms but rather a working clock face. The donor oscilloscope was a Heathkit IO-102 which was fine for its time but is now lacking, so the CRT was removed from its housing and placed in a custom-built enclosure with a 40s radio style that suits its new purpose well.
Seeing old hardware that is past its prime being put to work in a new way is great, both from a technical standpoint and also because that’s usable hardware that’s being kept out of the landfill. Oscilloscopes are popular for projects like these too since they are relatively easy to understand and modify. Besides being used as clocks,
we’ve also seen them modified to play video games such as Pac-Man
. | 11 | 8 | [
{
"comment_id": "6274966",
"author": "Bob",
"timestamp": "2020-09-01T23:44:11",
"content": "Love the mantle clock enclosure!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6274973",
"author": "Danjovic",
"timestamp": "2020-09-02T00:40:42",
"content... | 1,760,373,369.749537 | ||
https://hackaday.com/2020/09/01/this-3d-printed-bladeless-fan-gets-it-done-cheap/ | This 3D Printed “Bladeless” Fan Gets It Done Cheap | Tom Nardi | [
"ATtiny Hacks",
"home hacks"
] | [
"attiny85",
"bladeless fan",
"coanda effect",
"Digispark",
"dyson",
"esc"
] | Not long after Dyson unveiled their “bladeless” fan, a fairly steady stream of ever cheaper clones have been hitting the market. But this
3D printed version created by [Elite Worm] must surely be one of the most budget-friendly takes on the concept
. If you’ve got a 3D printer, we’d wager you’ve already got most of the parts required to build your own.
See, there’s a blade.
To be clear, of course there’s a blade. They aren’t magic, obviously. The fan is just small, and
hidden inside the base
. Air is pulled from the sides and bottom, and into the ring mounted to the top of the unit. When the air eventually exits the thin slit in the ring, it “sticks” to the sides due to the Coandă effect and produces a low pressure zone in the center. That’s all a fancy way of saying that the air flow you get from one of these gadgets is several times greater than what the little dinky fan would be capable of under normal circumstances. That’s the theory, anyway.
We can’t promise that all the physics are working as they should in this 3D printed version, but in the video after the break it certainly appears to be moving a considerable amount of air. It’s also quite loud, but that’s to be expected given it’s using a brushless hobby motor. To get it spinning, [Elite Worm] is using a Digispark ATtiny85 connected to a standard RC electronic speed control (ESC). The MCU reads a potentiometer mounted to the side of the fan and converts that to a PWM signal required by the ESC.
Beyond the electronics, essentially every piece of this project has been printed on a standard desktop 3D printer. An impressive accomplishment, though we probably would have gone with a commercially available propeller for safety’s sake. On the other hand, the base of the fan should nicely contain the shrapnel created should it explode at several thousand RPM. Probably. | 33 | 12 | [
{
"comment_id": "6274906",
"author": "scott.tx",
"timestamp": "2020-09-01T20:12:44",
"content": "dyson’s lawyers are warming up their suitcases I bet :P",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6274927",
"author": "Abryx",
"timestamp": ... | 1,760,373,369.960702 | ||
https://hackaday.com/2020/09/01/karting-hands-free/ | Karting Hands-Free | Brian McEvoy | [
"Games",
"Medical Hacks",
"The Hackaday Prize"
] | [
"als",
"assistive technolgy",
"Electrooculography",
"eyes",
"kart",
"motorized",
"quadriplegic",
"racing",
"steering",
"WheelChair"
] | Some of us have computer mice with more buttons than we have fingers, resolution tracking finer than a naked eye can discern, and forced-air vents. All these features presuppose one thing; the user has a functioning hand. [Federico Runco] knows that amyotrophic lateral sclerosis, ALS, or Lou Gehrig’s disease, will rob a person of their ability to use standard computer inputs, or the joystick on a motorized wheelchair. He is building
EyesDrive
for the 2020 Hackaday Prize, to restore that mobility to ALS patients. There are already some solutions, but this one focuses on a short bill of materials.
Existing systems are expensive and often track pupil location, which returns precise data, but EyesDrive only discerns, left, right, and resting. For these, we need three non-invasive electrodes, a custom circuit board with amplifiers, signal processing circuits, and a microcontroller. He includes a Bluetooth socket on the custom PCBs, which is the primary communication method. In the video below he steers a virtual kart around a knotty course to prove that his system is up to the task of an urban wheelchair.
EyesDrive by [Federico Runco] should not be confused with the
HackadayPrize2015 winner, Eyedrivomatic
, lead by two remarkable hackers,
Steve Evans
and
Patrick Joyce
.
The
Hackaday
Prize2020
is Sponsored by: | 3 | 2 | [
{
"comment_id": "6274913",
"author": "anon",
"timestamp": "2020-09-01T20:27:52",
"content": "I feel like the jitter in the video discredits the “up for the task” part a bit. In an urban enviornment I would want precision so I don’t accidentally spin to the right and kneecap someone with my chair. Th... | 1,760,373,369.997281 | ||
https://hackaday.com/2020/09/01/that-elusive-valve-amp-sound-for-not-a-lot-there-has-to-be-a-catch/ | That Elusive Valve Amp Sound, For Not A Lot! (There Has To Be A Catch) | Jenny List | [
"classic hacks",
"Hackaday Columns",
"Reviews"
] | [
"audio",
"THD",
"tube",
"tube audio",
"valve"
] | It was with considerable interest last month that I set out to track down where in the world there are still factories making tubes. My research found them in Slovakia, Russia, and China, and it’s fairly certain I didn’t find all the manufacturers by any means. There appeared to be a whole class of mundane tubes still in production that weren’t to be found on their glossy websites. A glance at any outlet through which Chinese modules can be bought will find this type of tube in small audio amplifier projects, and some of them can be astoundingly cheap. When faced with cheap electronics of course I’m tempted to buy some, so I parted with about £10 ($12.50) and bought myself a kit for a two-tube device described as a stereo preamplifier and headphone amplifier.
An Unusual Tube Choice For Audio
What I received for my tenner was a press-seal bag with a PCB and a pile of components, and not much else. No instructions, which would have been worrisome were the board not clearly marked with the value of each component. The circuit was on the vendor’s website and is so commonly used for these sort of kits that it can be found all over the web — a very conventional twin common-cathode amplifier using a pair of 6J1 miniature pentodes, and powered through a +25 V and -25 V supply derived from a 12 VAC input via a voltage multiplier and regulator circuit. It has a volume potentiometer, two sets of phono sockets for input and output, and the slightly naff addition of a blue LED beneath each tube socket to impart a blue glow. I think I’ll pass on that component.
The 6J1 seems to be ubiquitous throughout the Chinese kits, which is surprising when you understand that it’s not an audio tube at all. Instead it’s a small-signal VHF amplifier, a rough equivalent of the European EF95, and would be much more at home in an FM radio receiver or turret TV tuner from the 1950s. I can only assume that somewhere in China there’s a tube factory tooled up for radio tube production that is targeting this market, because another tube you will see in audio power amplifier kits is the FU32 or QQV03-20 in European parlance, a large power beam tetrode that might have been found in a 1950s military radio transmitter. Still just as if you were to use an RF transistor in an audio circuit it would give good account of itself, so it is with an RF tube. There is no reason a 6J1 won’t do an acceptable job in a circuit such as this one.
There are no surprises among the parts.
Other than in its slightly unusual power supply, there’s nothing at all remarkable about the preamplifier circuit. The 6J2 is wired as a triode, and because a common-cathode circuit is designed to drive a high impedance, it’s safe to assume this won’t be a very good headphone amplifier. It’s a simple preamp circuit that has graced the small-signal end of countless tube amplifiers, including
my youthful folly
.
Building the kit was as straightforward as any other through-hole design, and made for an enjoyable half-hour or so. There are no special things to note, I simply worked my way through it, first resistors, then diodes (but not those LEDs), transistors, capacitors and finally larger parts such as the potentiometer and sockets. A visual look over showed nothing of concern, so I plugged in the tubes and applied 12 VAC.
It’s amusing, this must be the first time I’ve ever used a
new
tube socket rather than one scavenged from old equipment, so I was unprepared for how stiff it was to plug in compared to one with years of heat cycles to soften its metal. On turning the kit on I was rewarded with a soft glow from the tube heaters, and measuring the voltages I found that it was generating about plus and minus 30 volts. A quick check applying some audio to it showed that it was indeed amplifying audio and it didn’t sound bad, but I needed a little more than that. It’s time to characterize the amplifier, is it any good?
Way Too Much Instrumentation For A Ten Quid Amplifier
An Audio Precision APx525 audio analyzer. Bradp723 (
CC-BY-SA 3.0
)
How do you characterize an amplifier, or any other piece of audio gear, for that matter? There are four metrics worth knowing: the gain, frequency response, phase response, and harmonic distortion. Frequency response relates to the range of frequencies it accepts, phase response relates to the phase shift between output and input at any given frequency, and harmonic distortion is usually expressed as a percentage of the output spectrum that is due to the non-linearities of the amplifier rather than having been present at the input. There are specialized instruments referred to as audio analyzers that will automate all these measurements by injecting a very high-purity sine wave into the device under test and measuring its output, but they are extremely costly and beyond the budget of a Hackaday scribe.
For this amplifier the frequency and phase responses are not likely to be concerning, so I would have to find a way to measure its distortion. Fortunately I was able to borrow a
Keithley 2015 precision multimeter
from a hackerspace friend, this very high quality instrument unexpectedly has a THD (Total Harmonic Distortion) function and its associated signal generator built-in. I suspect it may be aimed at the comms industry rather than the audio business, but it gives me what I need and I am very grateful to my friend. Set up alongside my trusty Rigol 1054z, I was ready to characterize the board.
Measuring THD with the Keithley 2015
I set up the generator at the ubiquitous audio testing frequency of 1 kHz, with a 100 mV pk-pk sine wave as input to simulate a lower-level audio source. The output at maximum volume was 4.85 V pk-pk, at which the THD was 1.31%. I calculate that as 37.31 dB. Adjusting the volume for unity gain, i.e. 100 mV pk-pk output, gave me a 0.03% THD reading. Giving it a 1V pk-pk input to simulate a line-level input gave me a significant level of visible clipping and an astronomical 32% THD at maximum gain.
What do these figures tell me? At low signal input levels it has the potential for a low THD, but even then it’s not into the three-digits-past-zero zone you’d expect to see in a high-end audio product. At higher levels it starts to degrade significantly, but given that it’s a preamplifier rather than a line-level amplifier that should be hardly surprising. It’s possible that some negative feedback would tame it, however I’d then be worried that its phase response might suffer.
The question is, does it matter that it’s not a super-high-end preamplifier? For ten quid spent, not really. If you keep the volume low enough and hook it up to your hi-fi it’ll sound decent enough, indeed that’s just what I did. And it sounds, well, like my hi-fi system. No special “warm valve sound”, but it did give me the momentary cachet of a pair of glass tubes on top of the stack.
Have I Bought A Masterpiece, Or A Toy?
There is one final thought with respect to this amplifier, and it returns to what I said earlier about its being described as a headphone amplifier by the vendor. A single-ended tube amplifier has a very high impedance output, which is to say it’s good at delivering voltage, but not current. Something with an impedance in the tens of kilo-ohms is fine for it to drive, but not a typical pair of headphones with an impedance in the tens of ohms. I didn’t even try, because I know that it wouldn’t do a very good job. All is not lost however, because it’s possible to make a simple headphone amp with this circuit if you’re prepared to add to it a little. Back in the day it might have had a step-down transformer on its output, but those are hard to find in 2020, so an alternative might be to
use a MOSFET source follower
as a buffer. It’s one of those projects that I might find myself returning to with this amplifier.
There’s a lot of talk among a certain section of the audio enthusiast community about something special surrounding a tube amplifier. Pseudo-technical explanations involving distortion in even harmonics are trotted out, and a lot of fancy tube hi-fi kit is fawned over. It’s true, that a good tube amplifier can be a very good amplifier indeed, but after having been right through this subject over decades I have my doubts over whether the mere presence of a tube confers anything extra-special.
I think it has its roots in the first generations of transistorized amplifiers in the 1960s and 1970s, when germanium transistors and single-ended power supplies requiring hefty electrolytic capacitors on the output delivered some models with not-very-good performance, but we’ve moved on since then. Superlative quality transistor amplifiers were a done deal decades ago, and while their tube siblings stand alongside them in quality, I think it’s dubious to claim too much else beyond saying that in audio as everywhere else: you get what you pay for. Buy one of these little kits and have fun playing with a tube circuit for pocket money prices, but don’t expect too much from it. | 54 | 17 | [
{
"comment_id": "6274860",
"author": "12AU76L6GC",
"timestamp": "2020-09-01T17:32:24",
"content": "Nice article. The amplifier has some negative feedback from the un bypassed cathode resistor and the really nice low level linearity you are seeing is probably just the center of the transfer curve.I’v... | 1,760,373,370.087532 | ||
https://hackaday.com/2020/09/01/a-guy-in-a-jet-pack-reported-flying-next-to-aircraft-near-lax/ | “A Guy In A Jet Pack” Reported Flying Next To Aircraft Near LAX | Mike Szczys | [
"drone hacks",
"News"
] | [
"drone",
"facepalm",
"jet pack",
"jetpack",
"LAX"
] | In case you needed more confirmation that we’re living in the future, a flight on approach to Los Angeles International Airport on Sunday night reported
“a guy in a jet pack” flying within about 300 yards of them
. A second pilot confirmed the sighting. It’s worth watching the video after the break just to hear the recordings of the conversation between air traffic control and the pilots.
The sighting was reported at about 3,000 feet which is an incredible height for any of the jet packs powerful enough to carry humans we’ve seen. The current state of the art limits jet pack tech to very short flight times and it’s hard to image doing anything more than getting to that altitude and back to the ground safely. Without further evidence it’s impossible to say, which has been
an ongoing problem with sightings of unidentified flying objects near airports
.
While superheros (or idiots pretending to be superheros) flying at altitude over the skies of LA sounds far fetched,
the RC super hero hack we saw nine years ago now
comes to mind. At 300 yards, that human-shaped drone might pass for an actual person rather than a dummy. This is of course pure speculation and we don’t want to give the responsible members for the RC aircraft community a bad name. It could have just as easily been trash, balloons, aliens, or Mothra. Or perhaps the pilot was correct and it was “some guy” flying past at 3,000 feet. That’s not impossible.
We anxiously await the results of the FAA’s investigation on this one.
[via
HN
and
TheDrive
] | 63 | 22 | [
{
"comment_id": "6274817",
"author": "steven",
"timestamp": "2020-09-01T15:49:22",
"content": "If someone could do this back then, imagine what they could do today.https://m.huffpost.com/us/entry/us_4157435",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6274... | 1,760,373,370.18096 | ||
https://hackaday.com/2020/09/01/potential-contenders-for-battery-supremacy/ | Potential Contenders For Battery Supremacy | Lewin Day | [
"chemistry hacks",
"Featured",
"Interest",
"Original Art",
"Slider"
] | [
"battery",
"Li-ion",
"liion",
"Lithium-ion battery"
] | Lithium ion batteries have been a revolutionary technology. Their high energy and power density has made the electric car a practical reality, enabled grid storage for renewable energy, and put powerful computers in the palm of the hand. However, if there’s one thing humanity is known for, it’s always wanting more.
Potential contenders for the title of ultimate battery technology are out there, but it will take a major shift to dethrone lithium-ion from the top of the tree.
Dominant For Good Reason
Lithium-ion batteries were first developed by Stanley Whittingham
, working at Exxon, who were looking to diversify away from oil in the midst of the major energy crises of the 1970s. Over the years, the technology was developed further, with work by John Goodenough (a superb hacker name if we’ve ever heard one) and Akira Yoshino increasing performance with improved cathode and anode materials. Commercialization was first achieved by Keizaburo Tozawa, working at Sony to
develop a better battery for the company’s line of camcorders
.
Many automotive battery packs, such as this Tesla unit, consist of thousands of cylindrical lithium-ion batteries not dissimilar from those commonly used in laptops.
The lithium-ion rechargeable battery has the ideal attributes for portable power, with high energy density and high power density, This means that it can store plenty of energy, and release it quickly for applications that draw lots of current. Low weight and high power output were game changing — technologies where size and weight matter, like quadcopter drones and powerful smartphones simply, wouldn’t be practical with older, heavier battery technologies.
In the years since, the world has fallen in love with lithium batteries. Different chemistries abound, optimising the batteries for more recharge cycles, higher power outputs, or lower cost. Saying production has skyrocketed in recent years is a bit of an understatement, with the coming of age of portable consumer electronics and the electric car revolution running almost entirely on rechargable lithium battery technology.
However, challenges remain. Electric cars are still somewhat range limited compared to their gasoline counterparts, and recharge times further frustrate the issue. Huge gains have been made in recent years, but automakers continue to strive for better performance as a competitive advantage. Additionally, while prices have dropped precipitously in the last ten years, lithium batteries still aren’t exactly cheap. Compounding this is a reliance on minerals that can be scarce or difficult to source. This has been particularly true of cobalt,
leading some manufacturers to explore alternative lithium-ion chemistries
, and we’re beginning to see success in completely removing cobalt from the equation.
There remains scope for alternative technologies to challenge lithium’s dominance of the battery industry. Any contender will need great energy density and power density, as well as the ability to last for thousands of charge cycles. Additionally, low cost, ease of manufacture, and being less prone to
catastrophic failure
, are all targets that battery researchers are trying to reach.
On the Cusp of Greatness?
The road from the lab to the factory is a long one, and many exciting projects run into intractable engineering issues long before reaching commercial sale. Breakthroughs are exactly that, the point at which hard problems are suddenly solved, so let’s look at what’s potentially on the cusp of greatness:
Solid State for Lithium Metal and Better Safety
Dendrite formation has long prevented the use of lithium metal anodes in Li-Ion batteries. Researchers believe solid state electrolytes may be the key to stopping dendrite formation, thus allowing the use of the anode material to create higher capacity batteries.
Lithium-ion batteries use liquid electrolytes of a variety of chemistries to tweak performance characteristics for particular applications. However, replacing this liquid with a solid state electrolyte is a hot research topic, as it promises a multitude of gains over current batteries.
Many hold the solid-state electrolyte as the solution that will enable the use of lithium metal anodes in batteries, replacing graphite in most current applications. Typically, lithium metal is an unstable anode material due to dendritic growth caused by chemical reactions with the liquid electrolyte. If a solid state electrolyte eliminated this problem, batteries could use the better performing lithium metal anode material. This would enable a huge gain in energy density, up to 2.5 times greater than conventional lithium-ion batteries.
The liquid electrolyte is also to blame for a lot of the danger inherent in lithium-ion batteries, becoming highly flammable, or even explosive, when a battery undergoes a thermal runaway condition.
Solid-state batteries may also solve this problem
, with reduced flammability compared to traditional liquid electrolytes.
There are still roadblocks in the way of full-scale uptake of solid state battery technology.
Conductivity issues at room temperatures continue to hamper the technology
. Manufacturing challenges also exist, with many designs requiring the use of vacuum deposition techniques. Regardless, many companies are pouring money into solid-state battery research,
with Samsung in particular working hard to develop the technology.
Lithium Air is Chasing the Energy Density of Gasoline
The charge and discharge cycles of a lithium-air battery. Relying on atmospheric oxygen gives the battery a better power-to-weight ratio, but atmospheric contaminants can cause problems.
Lithium-air batteries work by using oxygen in the atmosphere as a reactant. Oxygen donates electrons to the lithium via a carbon cathode.
Theoretically, such cells could have a specific energy of 11,680 Wh/kg
, close to that of gasoline at 13,000 Wh/kg — far exceeding contemporary battery technologies. Excluding the mass of oxygen, energy density per mass is up to 10 times higher than lithium-ion, meaning the technology would be ideal for increasing the range of electric vehicles.
A multitude of challenges face the lithium-air battery before it can successfully be commercialized. Chemical stability has been a problem of early efforts. Further development of cathode materials continues to bear fruit,
but best-case results from lab testing have cells lasting just two months in practice.
Charging efficiency is also low — just 65% of the energy put in during charging is usable. Additionally, the requirement for gaseous oxygen as a reactant poses further problems. While lab tests can use purified oxygen, atmospheric air contains carbon dioxide, water vapor, and other contaminants that can damage the battery. These would need to be filtered out in practical designs.
Flow Batteries
The basic operation of a typical flow battery.
Membraneless types are possible
, instead using laminar flow to ensure the two liquids touch but don’t excessively mix.
Flow batteries are a concept involving two liquids which are pumped through a membrane, exchanging ions and generating electricity in the process — you may remember reading
Kristina Panos’ article on liquid air energy storage
just a few weeks ago where the technology is being considered for grid storage.
As flow batteries rely on charge stored in liquid form, bigger batteries can be created by simply building bigger tanks for the reactants. The battery can be quickly “recharged” by simply replacing the electrolyte, or alternatively, it can be regenerated electrically like a traditional rechargeable battery.
The easy scaling makes the technology appealing for grid storage
, while the potential to be able to quickly “refuel” the battery would solve the problem of recharging electric vehicles quickly.
Despite their benefits, flow batteries have some drawbacks which have held them back from any serious use. Storing and pumping liquids is far more mechanically complex than traditional batteries, which can typically be treated as solid lumps of matter that may just require a little cooling now and then. This complexity and extra equipment reduces power density and makes flow batteries less practical for transport applications.
Most research focuses on energy storage for home and grid-level applications instead.
Conclusion
It may yet be some time before we see major change in battery technology in most of our devices. It’s likely that solid-state batteries that still rely on lithium chemistries will be the main contender that will overhaul lithium-ion’s dominance in the transport sector, with potential to follow in devices like laptops and smartphones. Lithium-air and flow batteries have further hurdles to overcome before they reach viability.
However, development continues on existing lithium-ion technology by academics and industry all over the world, particularly due to the demand in the automotive sector. With capacity and performance improving each year, we may yet continue to see classic lithium-ion remain as the battery of choice for quite some time to come. | 47 | 14 | [
{
"comment_id": "6274805",
"author": "Bunsen",
"timestamp": "2020-09-01T14:32:05",
"content": "In before CARBON-14 BETAVOLTAIC FREAKIN’ ROADWAYS.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6274810",
"author": "LightningPhil",
"timestamp":... | 1,760,373,370.263983 | ||
https://hackaday.com/2020/09/01/a-cyclopic-lcd-case-for-your-raspberry-pi-server/ | A Cyclopic LCD Case For Your Raspberry Pi Server | Tom Nardi | [
"Parts",
"Raspberry Pi"
] | [
"3D printed enclosure",
"nas",
"PoE",
"power over ethernet",
"private server",
"spi"
] | If you’ve got a personal website that needs hosting or a few hundred gigabytes of files that could use a centralized storage location, the Raspberry Pi’s small size and extreme energy efficiency make it a compelling server choice compared to that curbside Pentium 4 box you’ve been trying to find a home for. All you need is something to put in.
Of course there’s no shortage of Pi case designs ready to be extruded from your 3D printer, but we recently found ourselves
particularly taken with this unique one designed by [Ken Segler]
. It’s not only small and sleek with a dash of futuristic flair, but it includes a front-mounted two inch 240 x 320 IPS display that connects to the Pi over SPI. At the minimum that gives you a way to see all those beautiful boot messages on startup,
but with a little code
, it could provide you with various system statics and status messages at a glance.
While the LCD is clearly the star of the show here, the case also has a few other nice features that make it worthy of your consideration. The magnetically attached fan filter on the the top, for one. The stacked layout that puts the Pi directly above the SSD also makes for a relatively compact final product.
One thing to note though is that [Ken] is using Power-over-Ethernet, meaning there’s no spot for a dedicated power jack on the case. It’s an
easy enough feature to add into your own build
, but naturally not everyone’s network is suitably equipped. In that case, beyond the
normal annoyances of editing STL files
, it shouldn’t be too much trouble to add one in without having to
literally
hack your way through the printed plastic. | 20 | 7 | [
{
"comment_id": "6274763",
"author": "Marty",
"timestamp": "2020-09-01T11:22:54",
"content": "Maybe it could be more readable if we put a Fresnel magnifier in front.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6274862",
"author": "Gamma Raymond",
... | 1,760,373,370.464229 | ||
https://hackaday.com/2020/08/31/bright-white-night-light-fights-e-waste/ | Bright White Night Light Fights E-Waste | Kristina Panos | [
"green hacks",
"LED Hacks"
] | [
"acrylic",
"Circuit Sculpture",
"header",
"JST",
"night light",
"Nokia 5110 LCD",
"Nokia 5110 LCD display"
] | E-waste is a gigantic problem, and it can seem impossible as a lone individual to make any kind of dent in it. But [akshar1101] is trying to do their part by looking past the defective aspects of broken, discarded electronics to draw out the possibilities of what’s left.
This friendly night light is made from the PCBs of four broken Nokia 5110 LCD modules
. The screens were all toast, but the nice white LEDs that used to light them from the sides work just fine. [akshar1101] cleverly tied all the LED and GND lines together with single right-angle header pins. To power the LEDs, they wired up a JST receptacle to one of the PCBs and connected a 3.7 V lithium battery pack that sits underneath. [akshar1101] diffused the piercing white lights into a soft glow with two pieces of acrylic.
We love to see electronic components get saved from landfills, especially when they can be turned into something useful and beautiful. Something about the traces on these boards makes them visually interesting to us — it’s that little hiccup that interrupts otherwise parallel lines.
If all of your 5110 LCDs are in working order, you could
spice one of them up with an RGB backlight
. | 4 | 3 | [
{
"comment_id": "6274566",
"author": "mrehorst",
"timestamp": "2020-08-31T17:49:39",
"content": "How about powering it from one of the discarded chargers for those 4 dead phone LCD panels?",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6274719",
"aut... | 1,760,373,370.298795 | ||
https://hackaday.com/2020/08/31/rolling-blackouts-in-california-again/ | What’s The Deal With Rolling Blackouts In California’s Power Grid? | Bryan Cockfield | [
"Current Events",
"Featured",
"Interest",
"News",
"Original Art",
"Slider"
] | [
"blackout",
"CAISO",
"california blackout",
"climate change",
"grid",
"power grid",
"rolling blackout",
"wildfires"
] | A heat wave spreading across a large portion of the west coast of the United States is not surprising for this time of year, but
the frequency and severity of these heat waves have been getting worse
in recent years as the side effects from climate change become more obvious. In response to this, the grid operators in California have instituted limited rolling blackouts as electricity demand ramps up.
This isn’t California’s first run-in with elective blackouts, either. The electrical grid in California is particularly prone to issues like this, both from engineering issues and from other less obvious problems as well.
Infrastructure: An Old Problem
The physical problems with the electric grid are straightforward and covered often as part of the background noise of almost-forgotten issues with aging infrastructure systems as a whole. In a majority of North America, the electrical grid as well as roads, bridges, water and wastewater systems, airports, and virtually any other piece of infrastructure was largely built in the post-war boom following World War II and then essentially left to rot over the following decades. It takes a lot of maintenance to keep all of that infrastructure running, but it also takes political capital and a will to make sure that easily-forgotten things aren’t forgotten. As a result, maintenance budgets for virtually all infrastructure have been slashed resulting in
several major catastrophes
in recent years, as well as an
uncountable number of smaller inconveniences
that only signal an impending, slow collapse.
The electrical grid on the west coast of the United States is no exception. California experienced a population boom after World War II which continues to the present day. Most infrastructure problems, like elsewhere in the country, are only patched over while the entire system is barely upgraded to match demand. Anyone who has ever driven on a road in a major California city in the oppressive traffic will confirm this current state of affairs. When infrastructure is already taxed to its limits it only takes one straw to break the camel’s back. This straw was the
Camp fire of 2018
which, while not the first or last wildfire caused by an issue with a power line, was one of the most devastating. In addition to causing the deaths of at least 85 people and burning down 153,336 acres, this fire also caused the bankruptcy of California’s (and the United States’) largest energy company, PG&E, which is still struggling to recover.
Map of 2019 California rolling blackouts
as reported by Bloomberg
In fact,
these blackouts aren’t the first
(or likely, last) blackouts that California has seen even since the Camp fire. Last year a wave of rolling blackouts was instituted in northern California over the course of about a month as a result of increased fire risk. These more recent blackouts aren’t new, and unless a major overhaul of the grid is performed they will likely continue.
Sagging power lines may be a fire risk you haven’t considered before, but it’s one of threats at the front of grid operators’ minds right now. This year, California’s much hotter, drier summer has put additional strain on the electric grid as people ramp up use of air conditioning. However, more electricity on the stressed grid means more current in the wires, which means more resistive losses, which means that the wires expand more from that heat (not to mention the increased ambient heat from the heat wave itself) and they can sag into trees and other obstacles especially if the rights-of-way haven’t been maintained diligently. It’s a vicious feedback loop that puts a strained grid into a situation that can easily start fires, but is also the recipe for
massive cascade failures like the Northeast Blackout of 2003
. Despite this, efforts to upgrade the electric infrastructure are slow or non-existent. This is where we can start to see other non-engineering problems arise which are arguably worse.
Grid Operators Understand History
Most
reports of the recent rolling blackouts
(pay wall warning) indicate that the power grid was not operating at a capacity that would have necessarily required them, however perhaps out of an abundance of caution due to the heat wave and California’s history of power-line-induced fires the system operator decided to curtail power temporarily. There are
other reports of a sudden loss of generation due to a lack of wind
at the time, as California pushes to move more of their energy portfolio to renewables, however the system operator would typically have backup generation ready to bring online at any given moment, such as combustion turbines, hydroelectric plants, or other power plants, rather than resorting to rolling blackouts. While it is feasible that a sudden loss of wind may have contributed to the problem it shouldn’t have necessitated blackouts to solve, and with the amount of wind that California relies on this shouldn’t have been the first time they would have seen a problem like this either.
It’s important to note here that the operator of California’s electric grid is the California Independent System Operator (CAISO) which is a nonprofit that controls the bulk electric transmission system and is not actually an electric utility or in charge of any energy generation. The reason California has a system like this is convoluted but goes back to the passage of various legislation in the ’90s, the creation of the Federal Energy Regulatory Commission (FERC), and several other political moves over the course of about 15 years. Not every state or area has an independent operator like California, but due to these FERC requirements, and compounded by the Enron scandal, most utilities that operate their own bulk transmission system must at least behave independently. Although not directly a part of the larger accounting scandal that Enron is known for,
they played a major role in causing another set of rolling blackouts in California in the early ’00s
.
It’s easy to see the latest blackouts in two lights, both one of a straightforward engineering problem that needs to be solved, but also as part of a broader historical and legal issue that has gone back decades in California and will continue indefinitely, especially as the effects of climate change appear more and more. In fact, California has already
started on its wildfire season this year
and it is only the beginning, both for fires and for issues for the electric utilities in the state. | 148 | 34 | [
{
"comment_id": "6274488",
"author": "x3n0x",
"timestamp": "2020-08-31T14:30:40",
"content": "It is important to note in this circumstance is also the California Governments policy of OUTLAWING the use of energy sources like Natural AS for use in newer construction, thus making things like Water Hea... | 1,760,373,370.712207 | ||
https://hackaday.com/2020/08/31/100-printed-flashlight-conductive-filament-and-melted-in-leads/ | 100% Printed Flashlight: Conductive Filament And Melted-in Leads | Donald Papp | [
"3d Printer hacks",
"LED Hacks"
] | [
"3d printed",
"conductive filament",
"flashlight",
"led"
] | Conductive filament isn’t an
ideal
electrical conductor, but it’s a 3D-printable one and that’s what makes [Hercemer]’s
3D-printed flashlight using conductive filament
work. Every part of the flashlight is printed except for the 9 volt battery and LEDs. Electrically speaking, the flashlight is a small number of LEDs connected in parallel to the terminals of the battery, and turning it on or off is done by twisting or loosening a cap to make or break the connection.
The main part of the build is a 3D-printed conductive cylinder surrounded by a printed conductive ring with an insulator between them. This disk- or pad-shaped assembly forms not only the electrical connection between the LEDs and battery terminals, but also physically holds the LEDs. To attach them, [Hercemer] simply melts them right in. He uses a soldering iron to heat up the leads, and presses them into the 3D-printed conductive block while hot. The 9 V battery’s terminals contact the bottom when the end cap is twisted, and when they touch the conductive assembly the flashlight turns on.
Anode of each LED goes to the center, cathodes to the outside ring.
LED leads are melted-in with a soldering iron.
9 V battery pressed to the bottom of the conductive block lights up the LEDs.
Anticipating everyone’s curiosity, [Hercemer] measured the resistance of his conductive block and measured roughly 350 ohms when printed at 90% infill; lower infills result in more resistance. You can see a video of the assembly and watch the flashlight in action in the video, embedded below.
Heat-setting of the LED leads is clever, and allows a variety of LEDs to be mounted as needed. It’s a lot like
brass heat set inserts, which work well with 3D printed plastics
and could themselves make a good electrical connection in a similar build. | 28 | 9 | [
{
"comment_id": "6274456",
"author": "bebo",
"timestamp": "2020-08-31T11:39:12",
"content": "Yes!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6274464",
"author": "Osgeld",
"timestamp": "2020-08-31T12:40:49",
"content": "not even a single though ... | 1,760,373,370.530807 | ||
https://hackaday.com/2020/08/31/grasp-kotlins-coroutines-with-this-short-tutorial/ | Grasp Kotlin’s Coroutines With This Short Tutorial | Donald Papp | [
"Software Development"
] | [
"android",
"coroutine",
"kotlin",
"tutorial"
] | Kotlin is a relatively new programming language; a derivative of Java with lots of little handy functional bits such as
coroutines
. [Foalyy] is porting an app to Android and learning Kotlin at the same time, and
after wrapping their mind around coroutines, has written up a concise five-part tutorial on them
.
Coroutines in
Kotlin
are a way to simplify writing asynchronous code, which is code that doesn’t necessarily execute in the order it is written. Coroutines are like light-weight threads that can be launched and managed easily, making it simpler to bridge together blocking and non-blocking code. (However, coroutines are not threads. They are more akin to suspending functions that play very well together.)
[Foalyy] found that the
official Kotlin documentation on coroutines
went into great detail on how coroutines function, but wanted a more bottom-up approach to understanding how they work and can be used. Luckily for anyone who thinks the same way, [Foalyy] wrote it all up and begins with a great recap of important elements, but if you prefer you can
jump straight to the examples
.
Kotlin has been around for a while, and readers with sharp memories may recall it was featured
in this excellent introduction to what neural networks are and how they work
. | 1 | 1 | [
{
"comment_id": "6274600",
"author": "Guille",
"timestamp": "2020-08-31T19:18:34",
"content": "Every time I hear async and “coroutines” I think of Windows 3.0 “collaborative/reentrant multitasking”. I’m not saying it’s “the same”, but in the end it’s the same basic solution for the same problem, onl... | 1,760,373,370.746329 |
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