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https://hackaday.com/2020/01/07/how-low-can-an-esp32-go/ | How Low Can An ESP32 Go? | Jenny List | [
"handhelds hacks"
] | [
"ESP32",
"Memory LCD",
"Sharp Memory LCD",
"ULP"
] | Many of us have experimented with the ESP32 microcontroller, attracted by its combination of WiFi and a powerful processor core, but how many of us will have explored all of its many on-board features? One of the more interesting capabilities of this chip comes in the form of its ultra-low-power (ULP) co-processor, an extra core that allows an ESP32 to function while sipping tiny quantities of power with the ever-hungry main cores turned off.
It’s a feature that [Max Kern] has used to great effect in his
low power ESP32 handheld computer,
where he’s paired the chip with a low-power
Sharp Memory LCD
and used the ESP32’s ULP core to keep the display alive while the ESP cores are sleeping. Software wise the device sports basic PDA and clock functionality including an RSS parser, all of which can be seen in the video below the break. Its inspiration came from Panic’s crank-equipped Playdate console, with which it shares the Sharp display.
Seeing this device reminds us of some of the badges featuring ESP32 power that we’ve seen over the last few years. An event badge creator has a constant battle to give the device enough battery life to last the distance. It’s a problem the designers of the
SHA 2017 badge
solved with an e-ink unit, but perhaps the Sharp display could offer a cost-effective alternative for new designs. | 17 | 7 | [
{
"comment_id": "6208118",
"author": "mime",
"timestamp": "2020-01-07T10:03:09",
"content": "Jenny, you tease! Asking a question and then not giving the answer. But I suppose it does matter a lot what the sleep activity is. In this case 10uA, with 150 uA spikes.Thanks for this article, am very keen ... | 1,760,373,631.474309 | ||
https://hackaday.com/2020/01/06/the-internet-controls-this-monster/ | The Internet Controls This Monster | Rich Hawkes | [
"internet hacks"
] | [
"aiy voice kit",
"monster",
"raspberry pi",
"remo.tv",
"robot",
"text to speech"
] | What’s worse than unleashing a monster on the internet? Allowing the internet to control the monster! But that’s just what [8BitsAndAByte] did,
created a monster that anyone on the internet can control
. Luckily for us, this monster only talks.
This is a very simple project and most of the parts are off the shelf. Hardware wise the monster’s body is made out of a plastic flowerpot; its mouth is a bit of wood that covers the top of the flowerpot; its eyes, two halves of a plastic sphere painted white with some felt for irises. And then whole thing is covered in some blue fake fur.
Electronics wise, a Raspberry Pi is running the show and handling the text-to-speech is an AIY Voice Hat. A servo fits inside the flowerpot to open and close the monster’s mouth. On the software end of things, a bit of Python has been written that waits for a bit of text, sends it off to the Voice Hat’s text-to-speech module and moves the servo to open and close the mouth. The scary part, connecting the monster to the internet, is done with
remo.tv
, which is some open-source code hosted on GitHub specifically for allowing control of robots over the internet.
This is a neat little project which is simple enough that kids could build one themselves. The instructions and the python script are up on
the Instructables page
, and you can see the monster in action at its
page
on remo.tv. Perhaps [8BitsAndAByte] could add a couple of these
internet controlled robot arms
to the monster to create a monster that could create some real havoc!
https://www.youtube.com/watch?v=7WvK_5svj98 | 5 | 4 | [
{
"comment_id": "6208097",
"author": "Jonathan Newman",
"timestamp": "2020-01-07T07:15:53",
"content": "Reminds me of the internet controlled talking banana",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6208308",
"author": "kaaaaaaaaaang",
"... | 1,760,373,631.417277 | ||
https://hackaday.com/2020/01/06/full-duplex-radio-claimed-easier-with-analog-module/ | Full Duplex Radio Claimed Easier With Analog Module | Al Williams | [
"Wireless Hacks"
] | [
"diplexer",
"duplexer",
"noise cancellation",
"RF"
] | There’s an old saying that we have one mouth and two ears so you can listen twice as much as you talk. However, talking and listening at the same time is fairly difficult and doing it with radio signals is especially hard. A company called
Kumu Networks has an analog module that can use self-interference cancellation
which allows transmitting and receiving on the same frequency with around 50 dB of the transmitted signal in the transceiver. You can see a video about Kumu’s claims its technology below.
You may think that cell phones and ham radio repeaters transmit and receive at the same time, which of course they do, but usually on different frequencies to avoid direct interference. A diplexer is a device that sorts out the two frequencies while a duplexer sorts them out by the direction of the signal, but they are tricky to use. A duplexer can operate on a single frequency in applications such as radar, and even then it is still very difficult to prevent leakage from the transmitter from overloading and desensitizing the receiver.
While 50 dB might not sound like much, it is a factor of 100,000 which should open up new opportunities for radio transmitters and receivers to coexist even on the same frequency. The device is analog, so it uses circuitry to invert the transmitted signal and reincorporate it at the receiver.
IEEE Spectrum
recently had a post claiming the company is releasing the K6 module that can be “easily installed in most any wireless system.” RF can seem like black magic, but we can envision how this should work in theory. You’d need to adjust the phase of the inversion network to match the phase delay between where you pick up the signal (presumably before power amplification) and where you mix the canceling signal with the receiver.
Sounds good, but then again, noise-canceling headphones sound straightforward too and we all know that even an expensive pair can leave something to be desired. | 37 | 8 | [
{
"comment_id": "6208064",
"author": "ROB",
"timestamp": "2020-01-07T03:26:24",
"content": "50 dB whatIf your referring to power then dBW or dBmIf your referring to voltage the dBV",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6208068",
"author": "R... | 1,760,373,631.699863 | ||
https://hackaday.com/2020/01/06/reading-light-not-quite-powered-by-your-favorite-hot-beverage/ | Reading Light Not Quite Powered By Your Favorite Hot Beverage | Lewin Day | [
"green hacks",
"Misc Hacks"
] | [
"joule thief",
"peltier",
"reading light",
"seebeck"
] | Thermoelectric devices are curious things, capable of generating electricity via the Seebeck effect from a temperature differential across themselves. The Seebeck effect does not produce a huge potential difference, but when employed properly, it can have some useful applications. [MJKZZ] decided to apply the technology to build a reading light,
powered by a hot cup of coffee.
The build is based around four Peltier modules, 40mm x 40mm in size, sandwiched between a pair of copper sheets. The modules are wired in series to create a greater output voltage, and an aluminium heatsink is fitted to one side to create a higher temperature differential. The set-up produces just 230 mV from human body temperature, but over 8 volts when warmed directly with a heat gun. Boiling water in a mug produces a more restrained 2.1V output.
On its own, this voltage is a little weak to do anything useful. Thus, the electricity from the Peltier modules is fed through a joule thief, which helps step up the voltage to a more useful range to run an LED. With a mug of coffee on the copper plate, the assembly isn’t quite able to light the LED enough to allow the user to read comfortably. However, it flickers into life just a touch, demonstrating the basic concepts in action.
While it’s not the most practical build, and it’s likely to cool your coffee faster than you’d like, it’s a fun project that serves to educate about the mechanics of the Seebeck effect and using Peltier devices to generate it.
Another fun application is to use them in a cloud chamber
. Video after the break.
https://www.youtube.com/watch?v=HzPRsBQ4wzM&feature=youtu.be | 13 | 9 | [
{
"comment_id": "6208040",
"author": "Dion B",
"timestamp": "2020-01-07T00:03:57",
"content": "Try a copper Mint Julip Mug",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6208046",
"author": "Hirudinea",
"timestamp": "2020-01-07T00:35:13",
"content"... | 1,760,373,631.248897 | ||
https://hackaday.com/2020/01/06/a-homebrew-weller-rt-soldering-station/ | A Homebrew Weller RT Soldering Station | Tom Nardi | [
"ATtiny Hacks",
"Tool Hacks"
] | [
"atmel studio",
"soldering iron",
"soldering station",
"TM1637",
"Weller"
] | Like a number of hackers before him, [MarcelMG] was impressed with Weller’s RT soldering iron tips, but considerably less enthused about the high purchase price on the station they’re designed to go into. Inspired by similar projects, he decided to try his hand at
building his own soldering station which reaps the benefits of these active tips
without the sticker shock.
The station’s user interface was kept intentionally simple, with little more than a four digit LED display to show the temperature and a rotary encoder to set it. The display alternates between the current temperature and the set temperature every few seconds while the knob is being turned, and if you push it in, the set temperature will be saved as the default for next time.
[MarcelMG] also included a feature that drops the iron’s temperature when it’s sitting in the holder, reducing tip wear and energy consumption. He originally planned on using a Hall effect sensor to detect when the iron was holstered without needing to physically interface with it, but in the end he realized the easiest approach was to simply connect one of the input pins on the microcontroller to the metal holder. Since the tip is grounded, he could easily detect if it was in place with a couple lines of code.
Speaking of which, the station is powered by an ATtiny24A with firmware written in C using the Atmel Studio IDE. [MarcelMG] mentions that the limited storage on the 24A was a bit of a challenge to work around, and suggests that anyone looking to follow in his footsteps uses something with a bit more flash under the hood. The LED display is a very common TM1637 type, the rotary encoder was salvaged from a radio, and the power supply was from an old laptop. All told, this looks like a very economical build.
Depending on your needs, a DIY soldering station can either have
features to rival the commercial models
or
be exceedingly simplistic
. In either case, the advent of low-voltage irons and active tips have made self-built soldering stations much more approachable. Attempts without the use of these modern niceties
tended to be somewhat less glamorous
. | 15 | 4 | [
{
"comment_id": "6208004",
"author": "big F",
"timestamp": "2020-01-06T21:09:50",
"content": "Great build. Wonder if it will fit inside the standard Weller workstation base unit , which reminded me I have my Weller workstation Soldering Iron waiting for me to copy the ceramic Pcb to a normal pcb af... | 1,760,373,631.536188 | ||
https://hackaday.com/2020/01/06/the-hacker-history-of-music-technologies/ | The Hacker History Of Music Technologies | Lewin Day | [
"cons",
"Musical Hacks"
] | [
"2019 Hackaday Superconference",
"Hackaday Supercon",
"music"
] | Music throughout history has been inspired and changed by hackers and makers, and never moreso than in the 20th century. Helen Leigh is one such hacker, who brought a talk to Supercon to give us
a crash course in the history of recording, electronics and music, and what the maker movement is doing
in the music world today.
The tape recorder was an invention that kicked off a golden period of exploration in sound. Beginning in World War II, the Nazi propaganda machine cut and spliced recorded materials and disseminated them across broadcasting stations in Europe. To the astonishment of the Allies, certain German officials appeared to be making broadcasts from different studios at the same time, due to the high quality of the recording hardware. After the war, this technology was discovered by a group of Parisian recording artists who began to experiment with an art that became known as
musique concrète,
using tape hardware in weird and wonderful ways to create new sounds heretofore unheard in nature.
Daphne Oram was an early proponent of advanced recording techniques, and founded the BBC Radiophonic Workshop.
Helen’s talk explores this movement as an excellent example of the hacker ethos applied to musical creation. While much of the artistic output was amelodic and somewhat
challenging
to listen to, it nevertheless had a great impact on recording technology and techniques.
Helen recounts the work of Daphne Oram, who, inspired by
musique concrète,
went on to perform her own experiments, and eventually founded the BBC Radiophonic Workshop. This hallowed organisation became a hotbed of electronic and musical experimentation, developing innovative techniques in foley and laying the foundations for modern electronic music.
Particularly note worthy is the work done in the creation of the original
Doctor Who
theme song. Produced in the BBC Radiophonic Workshop by Delia Derbyshire, it was created entirely electronically from a score by Ron Grainer. In 1963, synthesizers weren’t readily available; instead, the whole composition was brought to life with signal generators, test equipment, tape loops, and recordings of white noise. Lengths of tape were cut and stuck back together with tape to produce the various parts of the track, with recordings sped up and slowed down to create the necessary pitch changes. Multitrack tape recording was not yet available, and thus the final mix was created by playing back several tapes all at the same time, with some necessary fussing required to get them all in sync. The cutting-edge production foreshadowed many innovations to come in recording technology.
[Helen]’s own mini.mu product helps educate children in hardware hacking and musical expression.
With plenty of focus on the dawn of the art, Helen then moves on to discuss the current state of play. A hat tip is given to [LOOK MUM NO COMPUTER] and his famous
Furby Organ
; just one of many creations that have come out of the lab,
some of which we’ve featured before
.
Helen is prolific as a creative technologist, producing many builds that experiment with sound and music in their own way. Building hardware as diverse as musical ferns and choker-mounted vocoders, she’s pushed the envelope in what’s possible. Having produced a series of interactive sound sculptures, Helen has found that capacitive touch and gesture interactions are a key technology in this space, creating a natural and intuitive interface with the hardware. It’s a technique that can have pitfalls, particularly with wearable designs, but Helen’s perseverance and skill has overcome such challenges. Other works involve creating commercial products like
the Mi.Mu advanced glove interface
, and pushing cheap microcontrollers to do “more than just chiptunes”. With a passion for education as well as experimentation, there’s also a strong discussion of how community leads to ever greater creative output.
Helen’s Supercon talks serves as a great lesson on the history of hacking and music, as well as a tantalising primer for those keen to get involved today. It’s certainly opened our eyes to new possibilities, and we can’t wait to see what comes next! | 7 | 4 | [
{
"comment_id": "6208057",
"author": "ROB",
"timestamp": "2020-01-07T01:54:18",
"content": "There were wire recorders even before tape recorders.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6208063",
"author": "Uniservo",
"timestamp": "202... | 1,760,373,632.003785 | ||
https://hackaday.com/2020/01/08/engineering-your-way-to-better-sourdough-and-other-fermented-goods/ | Engineering Your Way To Better Sourdough (and Other Fermented Goods) | Kristina Panos | [
"chemistry hacks",
"cons",
"cooking hacks"
] | [
"2019 Hackaday Superconference",
"fermentation",
"kombucha",
"peltier",
"peltier unit",
"sourdough",
"sourdough starter",
"wild yeast",
"yeast"
] | Trent Fehl is an engineer who has worked for such illustrious outfits as SpaceX and Waymo. When he got into baking, he brought those engineering skills home to solve a classic problem in the kitchen: keeping a sourdough starter within the ideal, somewhat oppressive range of acceptable temperatures needed for successful fermentation.
A sourdough starter is a wad of wild yeasts that you make yourself using flour, water, and patience. It’s good for a lot more than just sourdough bread — you can scoop some out of the jar and use it to make pancakes, waffles, pretzels, and a host of other bread-y delights. A starter is a living thing, a container full of fermentation that eats flour and has specific temperature needs. Opinions differ a bit, but the acceptable temperature range for active growth is about 60 F to 82 F. Too cold, and the starter will go dormant, though it can be revived with a little love. But if the starter gets too hot, all the yeasts and bacteria will die.
While there are of course commercial products out there that attempt to solve this problem of temperature control, most of them seem to be aimed at people who live in some wonderland that never gets warmer than 80F. Most of these devices can’t cool, they only provide heat. But what if you live in a place with seasons where the climate ranges from hot and humid to cold and dry?
The answer lies within
Chamber
, a temperature-regulated haven Trent created that lets these wild yeasts grow and thrive. It uses a Peltier unit to heat and cool the box as needed to keep the mixture fermenting at 26°C /78.8°F.
Thanks to the Peltier unit, Trent can change the temperature inside the chamber simply by alternating the direction of current flow through the Peltier. He’s doing this with an H-bridge module driven by a Raspberry Pi Zero. When it starts to get too warm in the chamber, the fan on the outside wall vents the heat away. A second fan inside the chamber pulls warm air in when it gets too cold.
Trent says that Chamber performs really well, and he’s recorded temperatures as low as 60F and as high as 82F. He mostly uses it for sourdough, but it could work for other temperature-sensitive food sciences like pickling, growing mushrooms, or making yogurt. We think it could be ideal for fermenting kombucha, too.
Chamber works well enough that Trent has put further development on the back burner while he makes use of it. He does have several ideas for improvements, so if you want to help, check out
his website
and
Github repo
. | 23 | 10 | [
{
"comment_id": "6208618",
"author": "Segdop",
"timestamp": "2020-01-08T20:29:49",
"content": "This would be perfect for cultivating grain spawn jars for mycology",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6208650",
"author": "Daniel",
"t... | 1,760,373,631.379283 | ||
https://hackaday.com/2020/01/08/commercial-circuit-simulator-goes-free/ | Commercial Circuit Simulator Goes Free | Al Williams | [
"Hackaday Columns",
"Slider",
"Tool Hacks"
] | [
"LTSpice",
"micro-cap",
"simulation",
"SPICE"
] | If you are looking for simulation software, you are probably thinking LTSpice or one of the open-source simulators like Ngspice (which drives Oregano and QUCs-S), or GNUCap. However, there is a new free option after the closing of Spectrum Software last year:
Micro-Cap 12
. You may be thinking: why use another closed-source simulator? Well, all the simulators have particular strengths, but Micro-Cap does have very nice features and used to retail for about $4,500.
The simulator boasts a multipage schematic editor, native robust digital simulation, Monte Carlo analysis, 33,000 parts in its library, worst-case and smoke analysis, Smith charts, and it can even incorporate spreadsheets. There’s a built-in designer for active and passive filters. Have a look at the
brochure
and you will see this is a pretty serious piece of software. And now it’s at least
free as in beer
.
Models
The number of models supported for active devices is impressive and includes some very recent MOSFET models, not just the old standard models. It can also read just about any regular Spice or IBIS model. It can also export Spice files if you want to use another engine or share designs with other Spice users. There are also quite a few examples provided. There are also over 2,000 standard digital parts including all the usual 7400 families, CD4000 CMOS, and even ECL.
As a bonus, we tried it under Wine and it worked well — at least the 32-bit version. The 64-bit one would probably work with a little effort. On a big monitor, you might want to use Winecfg to set a higher DPI setting, although the toolbar icons are fixed in size which is a little inconvenient. You can, however, select “large toolbar” on the Options | Preference menu, which will help.
Features
One nice touch is that you can view a simulation and interactively change component values and watch the results update right away.
We frequently use Spice when we are too lazy to do the math required to pick an optimal set of values. With this software, you can set ranges for various circuit components, tell the program what you want to optimize, and it will compute the best values for you.
The smoke analysis is somewhat unique. The idea is to run a transient analysis and the program determines if any circuit values exceed the maximum value for a component. You get a nice colored graph that tells you how close you are to smoke or, if you have some red bars, what parts will smoke.
Another neat feature is that you can create very cool 3D plots. This is especially useful if you are stepping parameters or measuring the effect on parameter variation like temperature.
One other feature we liked is that the program can output a netlist for printed circuit board programs including Protel, Accel, Orcad, and PADS. Over 18,000 components in the library have packages available and there is a package editor. We wish it would work with KiCAD, although we are pretty sure you could figure out some conversion path from one of the formats available.
Why Free?
The software was under development since 1982. We don’t know the circumstances of Spectrum’s closing but we hope it was to move on to something great. However, we appreciate the free release of this powerful simulator that can give LTSpice a run for its money. True, we expect there won’t be future development, but the package seems very complete and with the ability to import models, it will be very useful for a long time to come.
Learning
If you are trying to learn the program, there are some
starting instructions
for an older version that should get you the basics. You can also find the user’s manual and a reference manual on the site.
We went looking for tutorials and found that [Kiss Analog] just started a set of video tutorials. There’s only one complete, so far (see below), but we are sure there will be more on the way.
If you’d rather do LTSpice, we have
a tutorial
. Then again, for just playing around, the
Falstad simulator
is pretty nice and requires no installation. | 118 | 34 | [
{
"comment_id": "6208577",
"author": "Ostracus",
"timestamp": "2020-01-08T18:05:40",
"content": "The “Blender” of circuit-simulation.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6208591",
"author": "Harvie.CZ",
"timestamp": "2020-01-08T18:... | 1,760,373,631.956175 | ||
https://hackaday.com/2020/01/08/titanium-coating-is-actually-pretty-straightforward/ | Titanium Coating Is Actually Pretty Straightforward | Lewin Day | [
"Science"
] | [
"coating",
"metal coating",
"sputtering",
"titanium"
] | [Justin] enjoys tinkering in his home lab, working on a wide variety of experiments. Recently, he’d found much success in coating objects with thin layers of various metals with the help of a DC sputtering magnetron. However, titanium simply wouldn’t work with this setup.
Instead, [Justin] found another way.
As it turns out, coating with titanium is quite achievable for even the garage operative. Simply run current through a titanium wire, heating it above 900 degrees in a vacuum. This will create a shower of titanium atoms that will coat virtually anything else in the chamber. [Justin] was able to achieve this with little more than some parts from Home Depot, a vacuum pump, and a cheap glass jar. He was able to produce a nice titanium oxide finish on a knife blade, giving that classic rainbow look. Coating crystals was less straightforward, but the jet black finish achieved was impressive nonetheless.
[Justin] plans to upgrade his vacuum rig further, and with better process control, we’d expect even better results.
The earlier work is also very relevant if you’re interested in creating fine coatings of other materials
. Video after the break. | 28 | 8 | [
{
"comment_id": "6208555",
"author": "Harvie.CZ",
"timestamp": "2020-01-08T16:39:40",
"content": "Can this be achieved in low vacuum? How high vacuum i need for this? Can this be achieved in vacuum produced by venturi ejector?",
"parent_id": null,
"depth": 1,
"replies": [
{
... | 1,760,373,631.315866 | ||
https://hackaday.com/2020/01/08/the-barcode-revolution-welcome-to-our-automated-world/ | The Barcode Revolution: Welcome To Our Automated World | Maya Posch | [
"Featured",
"Interest",
"Original Art",
"Slider"
] | [
"bar code",
"barcode",
"Bokode",
"EAN",
"upc",
"UPC-A"
] | Featured in many sci-fi stories as a quicker, more efficient way to record and transfer information, barcodes are both extremely commonplace today, and still amazingly poorly understood by many. Originally designed as a way to allow for increased automation by allowing computer systems to scan a code with information about the item it labels, its potential as an information carrier is becoming ever more popular.
Without the tagging ability of barcodes (and their close cousin: RFID tags), much of today’s modern world would grind to a halt. The automated sorting and delivery systems for mail and parcels, entire inventory management systems, the tracing of critical avionics and rocketry components around the globe, as well as seemingly mundane but widely utilized rapid checkout at the supermarket, all depends on some variety of barcodes.
Join me on a trip through the past, present and future of the humble barcode.
Removing the Human Element
KarTrak barcode on the side of a rail car.
Way back in the 1930s, John Kermode, Douglas Young, and Harry Sparkes of Westinghouse Electric Co were
listed as the inventors
of an automated card sorter system. This system used a number of bars printed on paper, which would be read by a photo-electric cell, in turn triggering the card (statement, invoice, etc.) to be dropped through a specific trap door, sorting the item into the appropriate bin.
With the goal of the system was to speed up mundane tasks and to reduce the burden of having humans keep track of things like railcars, mail trucks, and other elements in the ever-increasing web of logistics that began to span the USA in the 20th century,
automatic equipment identification
(AEI) systems such as
KarTrak
were developed. This system was intended to allow the US railroad to keep track of its rolling stock.
A plate with 13 horizontal labels of varying dimensions and colors was mounted on either side of a car, from where a track side scanner would record the pattern and register the car it was attached to.
Modern AEI tag on rail car.
Unfortunately, KarTrak’s barcode labels proved to be too unreliable in actual use, with dirt accumulation and damage to the labels being the main reasons why the system was eventually phased out by the late 1970s. These days an RFID-based AEI system is used instead, which is immune to such issues. Cases like these proved that the main limitation of barcodes will always be one of visibility, much as a paper barcode can be damaged, drawn over, or torn off.
This limitation is however not as much of an issue in production environments, warehouses and retail stores, which is where they are most commonly used instead of RFID tags.
Scan It and Bag It
As early as the 1940s, attempts were made to invent a system that would automate parts of the checkout process in grocery stores, especially to look up and tally the prices. In 1948, graduate student
Bernard Silver
overheard the president of the local Food Fair food chain ask one of the deans to develop a system that would automatically read product information during checkout.
A photomultiplier tube (PMT).
Silver would tell his friend
Norman Woodland
about this, and together they set out to develop such a system. After an initial failed attempt with ultraviolet ink, Silver would use the basic concept behind Morse code for creating the lines, essentially extending the dots and dashes downwards. Taking a page from the movie industry, he opted to use a
photomultiplier tube
along with a 500 Watt incandescent light bulb for reading the barcodes.
In their 1949 patent application, they described both this linear barcode, as well as a ‘bull’s eye’ version, which Silver deemed would be more efficient and easier to read. When Woodland moved to IBM in 1951, he tried to interest IBM in the system. Though he was successful in this, it was concluded that the technology necessary to make it work was still unavailable at the time.
It wouldn’t be until the 1960s that the topic would come up again, with IBM at Research Triangle Park in North Carolina assigning
George Laurer
(who sadly passed away in early December of 2019) to lead the team that would go on to create what is now known as the UPC-A barcode. This team consisted of William Crouse (inventor of the Delta C bar code), Heard Baumeister (calculating achievable characters per type of barcode), Norman Woodland (who still worked at IBM) and near the end of the project mathematician David Savir.
Reading patterns for the bulls-eye, Delta A, B and C barcodes.
Near the end of the project the team was dissolved leading to some glitches in the development effort. Laurer made some changes to the Delta C barcode without applying Baumeister’s equations — making the read error rate skyrocket — but the
GS1
retail organization ultimately accepted this Delta C barcode proposed by IBM as the UPC-A
Universal Product Code
barcode that would go on virtually unchanged to this day.
The most notable change to the system is the
Internal Article Number
(EAN) superset of UPC-A. EAN adds an extra digit to the beginning of the number, expanding the theoretical number of unique values to one trillion, indicating the country (using GS1 country codes) in which the company selling the product is based. These days essentially all barcodes used in retail are the EAN-13 type.
Enter the Matrix
A simple QR code.
Although these types of one-dimensional barcodes were and still are very useful, it was realized that by adding a second dimension, one could scale up the amount of information contained in a tag. Helped by improving scanners and ever cheaper CMOS and CCD image sensors, matrix barcodes like the QR code were developed. The QR (‘Quick Response’) code was developed by the Japanese company
Denso Wave
, back in 1994 (
25 years ago
) for use in the car industry.
This type of barcode was designed to contain information needed to track vehicles during manufacturing, allowing for rapid scanning using a single frame of image data. By having the position markers at the corners in the matrix barcode, it is easy to determine when one has a complete enough image to parse it.
These days QR codes are used anywhere a smartphone user might need quick access to some kind of information without manually copying strings of characters, including URLs, WiFi network login credentials or arbitrary strings of data. The ability to scan 1D and 2D barcodes is a standard feature of such smartphones, as no extra hardware is required, courtesy of miniature camera technologies one could only dream of back in the 1970s.
A number of Data Matrix barcodes on a WiFi card.
QR codes are obviously not the only type of matrix barcode. Electronic components are often marked with a
Data Matrix
barcode. This type of matrix barcode allows for very small tags that are readable even in poor lighting conditions. This makes it useful for tracking small components.
This type of barcode is often found on electronic components, on inventory tags, food labels. It can store from a few to up to 1,556 bytes of data, depending on the number of cells in the matrix. This is similar to QR codes, which can be tiny tags (e.g. a 21×21 matrix) or large (e.g. 177×177 matrix) with corresponding physical size.
As can be seen on the WiFi card image, the size of the chosen barcode depends on the amount of information to be encoded. Not only can one scale the barcode itself, the maximum amount of data that can be encoded also depends on the size of the matrix with the overhead from the padding, orientation markings and error correction all having to be taken into account.
As anyone who has ever tried to scan a blurry, damaged, or ridiculously tiny QR code can probably attest, achieving reliable scanning results demand you keep all of those factors in mind. What use is a high-tech matrix barcode after all if it can no longer reveal the data it contains?
Welcome to the Future
Whereas until the 1990s the reliable scanning of barcodes was anything but easy, today’s technologies have made it possible to quite literally put a highly capable 1D and 2D barcode scanner in everyone’s pocket. New technologies have made some look at creating the first
3D barcodes
, which would make imprints in a material with 0.4 micron resolution, to be read out with an interferometer setup. This complexity can be used to fight things like counterfeited medication.
A Bokode tag taken in- and out of focus.
The number of 1D and 2D barcodes has quite literally exploded in number, as
we noted back in 2015
and
again in 2018
when the JAB (Just Another Barcode) joined the party with color instead of black and white markings to increase data depth per dot. Few of them are as insanely awesome as the
Bokode tag
, however, which takes ‘miniature’ to a whole new level courtesy of advanced optics. Bokodes can also be powered and rewritable, while being readable from up to 4 meters.
With the
Wikipedia page for ‘Barcode’
alone listing around a hundred 1D and 2D barcode types, and with many new ones in development, it appears that we may just get that sci-fi future where barcodes are more common than human-readable text. That is, until we finally get those barcode reader upgrades for our cybernetic eyes. | 25 | 10 | [
{
"comment_id": "6208528",
"author": "socksbot",
"timestamp": "2020-01-08T15:14:32",
"content": "I’m still impressed by the algorithms that allow a feature phone from the 00’s to detect the fiducial features of a 2D barcode in a blurry image. Any chance of a primer on those?",
"parent_id": null,... | 1,760,373,631.625779 | ||
https://hackaday.com/2020/01/08/an-esp8266-environmental-monitor-in-your-usb-port/ | An ESP8266 Environmental Monitor In Your USB Port | Tom Nardi | [
"Microcontrollers"
] | [
"AHT10",
"CH330",
"environmental monitor",
"ESP8266",
"humidity sensor",
"temperature sensor"
] | At this point, we’ve all seen enough ESP8266 “weather stations” to know the drill: you just put the ESP and a temperature sensor inside a 3D printed case, and let all those glorious Internet Points™ flow right on in. It’s a simple, and perhaps more importantly practical, project that seems to never get old. But that doesn’t mean there isn’t room for innovation.
Annoyed by the unnecessary bulk of existing solutions, [cperiod] has come up with
an ESP8266 temperature and humidity sensor that can plug directly into a standard USB port
. Slotted into a USB wall charger or power bank, this diminutive board can provide inconspicuous remote environmental monitoring wherever you need it. For extra hacker points, the board was even produced at home on a PCB mill.
In addition to the ESP-7 or 12 module (which plugs in via a header, should you need to swap it out), the board features a
CH330N USB to UART chip
and HT7233 voltage regulator. For the sensor itself, [cperiod] has bucked convention a bit and went with the I2C-connected AHT10 over something more common like a member of the BME family.
Unfortunately, this design suffers from the same issue we’ve seen in other compact environmental monitoring solutions; namely, that the heat generated by the chip itself skews the temperature readings. To combat this, aggressive power saving functions are baked into the firmware to make sure the ESP is in a deep sleep as much as possible. While not a perfect solution, it does prevent the ESP from warming the PCB up so much that it invalidades the reported data.
By now, the particularly astute reader may have realized that all the additional components used for the USB side of this board aren’t
strictly
necessary. After all, if you can
pull the ESP module out of the header and program it separately
, then you don’t actually need to include that capability in each sensor node. While true, we’re hardly the ones to complain when a hacker showboats a bit on their designs. | 28 | 12 | [
{
"comment_id": "6208503",
"author": "elcouz",
"timestamp": "2020-01-08T12:51:49",
"content": "Not a good idea… unless used with a USB extension cord computers will offset the temperature since they generate heat especially on back USB ports.",
"parent_id": null,
"depth": 1,
"replies": [... | 1,760,373,632.071946 | ||
https://hackaday.com/2020/01/08/the-ruscombe-gentlemans-steam-bicycle/ | The Ruscombe Gentleman’s Steam Bicycle | Danie Conradie | [
"Transportation Hacks"
] | [
"bicycle",
"live steam",
"motorized bicycle",
"steam-powered"
] | Cycling for health and transportation might seem like a good idea, but it unfortunately has the nasty side effect of making you tired. To ease the suffering, many have turned to electric bicycles. But what if you want to really stand out from the crowd? Well then you should look to [Mark Drake] for inspiration, the creator of the beautifully engineered
Ruscombe Gentleman’s Steam Bicycle
.
[Mark] wanted to create a steam powered bicycle that’s actually usable, instead of just an awkward novelty. To achieve this he made extensive use of modern tech like spreadsheets to model the steam cycle, and CAD for the mechanical design. The engineering design that went into the project really shows in level of refinement of the end product, which is able to comfortably reach 15 mph. Watch the video after the break to see it in action and get all the details.
Petrol is used a fuel source, which is forced to the vaporising burner via air pressure. The fuel is heated by the burner itself to form a vapour before entering the combustion chamber and igniting. The steam generator is a hybrid design, using both mono tube steam generator coils and a small fire tube boiler. This produces superheated steam at over 300 °C, which [Mark] says is key to the bike’s performance. Mineral oil can’t handle the high temperature, so modern synthetic oil is used for lubrication. The steam generator is so well-built that [Mark] managed to get is certified to industrial standards. For safety, it features both a pressure release valve, and a system that automatically shuts of the fuel supply when the steam exceeds a certain pressure. 130 W of power is provided to the wheels by a single cylinder slide valve engine via modern toothed belt. This also drives the air pump to keep the fuel system pressurised, and an adjustable water pump to feed the boiler.
The range of the bike is limited to 16 miles by the water supply, since all steam is exhausted to atmosphere. [Mark] hopes to improve this by adding a condenser to the system to recapture some water. He also wants to add a feed water heater to preheat the water using the exhaust steam, and increase fuel efficiency.
We’ve covered a few steam bicycles over the years including
wood fired
and
recumbent versions
.
Thanks [Kelvin Ly] for the tip! | 16 | 9 | [
{
"comment_id": "6208461",
"author": "ThisGuy",
"timestamp": "2020-01-08T09:54:04",
"content": "At 300°C steam temperature, he could probably also gain a lot of efficiency by going to a 2 cilinder expansion engine design with a high and low pressure cilinder to make better use of the thermal content... | 1,760,373,632.127209 | ||
https://hackaday.com/2020/01/07/poking-around-inside-a-pair-of-classic-gaming-gifts/ | Poking Around Inside A Pair Of Classic Gaming Gifts | Tom Nardi | [
"classic hacks",
"Games"
] | [
"Binwalk",
"classic game",
"firmware dump",
"firmware hacking",
"retro gaming"
] | Retro gaming is huge right now, and like probably millions of other people, [wrongbaud] found himself taking possession of a couple faux-classic gaming gadgets over the holidays. But
unlike
most people, who are now using said devices to replay games from their youth,
he decided to tear into his new toys to see how they work
.
The first to get pulled apart is a handheld
The Oregon Trail
game, which Hackaday readers may recall from
a teardown we did back when it was first released
. His work continues right where our teardown left off, by pulling the game’s two EEPROM chips out and dumping their contents. As expected, [wrongbaud] found that the I2C connected chip contained the game save information, and the SPI flash chip stored the actual game files.
Next up was an HDMI “stick” from Bandai Namco that allows the user to play a selection of NES games. Here again [wrongbaud] liberates the flash chip and dumps it for examination, this time using an ESP32 tool of his own creation. Inside the firmware image he’s able to identify several elements with the help of
binwalk
, such as splash screen graphics and text strings.
But perhaps most interestingly, he found that
binwalk
was able to automatically extract the NES ROMs themselves. After verifying they were standard ROMs with an NES emulator, he theorizes that repacking the firmware with different ROMs should be possible should anyone feel so inclined.
Both of these hacks are fantastic examples of how you can reverse engineer a device’s firmware with low cost hardware, open source tools, and a healthy dose of patience. Even if you aren’t interested in fiddling with
The Oregon Trail
or swapping out the
Mappy
ROM for
Contra
, this write-up is an invaluable resource for anyone looking to do their own firmware analysis.
This isn’t the first time [wrongbaud] has hacked around inside these extremely popular retro games, either. Just last month we covered some of his
previous exploits with the re-released versions of
Rampage
and
Mortal Kombat
. | 5 | 3 | [
{
"comment_id": "6208430",
"author": "scott.tx",
"timestamp": "2020-01-08T06:13:44",
"content": "bookmarking that site for future reference, nice!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6208462",
"author": "Alex Rossie",
"timestamp": "2020-01-0... | 1,760,373,632.231617 | ||
https://hackaday.com/2020/01/07/spintronic-ram-gets-a-little-closer-to-sram/ | Spintronic RAM Gets A Little Closer To SRAM | Al Williams | [
"Science"
] | [
"hall effect",
"magnetoresistance",
"MRAM",
"ram",
"USMR"
] | Sometimes it seems as though everything old is new again. The earliest computers used magnetic memory such as magnetic core. As practical as that was compared to making for example each bit of memory be a vacuum tube or relay flip flop, newer technology such as SRAM and DRAM displaced core and similar technologies. However, some of the newest technologies once again use magnetic fields. FRAM or ferroelectric RAM and magnetoresistive or MRAM both use magnetic fields to store data. Now Japanese researchers think they are on track to make
MRAM more competitive with traditional RAM chips
.
The Tokyo Institute of Technology researchers use new material combinations to make chips that store data based on the spin of electrons — the underlying reason for the way magnets behave. Their recent paper discusses USMR or Unidirectional spin Hall magnetoresistance and using this effect could greatly simplify the construction of MRAM cells.
How much simpler? Conventional MRAM requires up to 30 fabrication layers. The new technology requires only two.
There are two different exotic materials and the magic happens at their interface, at which electrons with the same spin accumulate. By injecting them into the ferromagnetic layer, that layer flips its magnetic field. This works as a write operation and also changes the resistance of the structure due to USMR. An external circuit can measure this resistance change, but it is very small, especially in conventional MRAM cells — less than a 1% change.
The new materials break the 1% barrier. This makes them much simpler to read and combined with the easier fabrication should result in cheaper and denser MRAM devices.
There have been
many memory technologies
used over the years to store data. Among them were the really odd devices like the
Radechon
. | 16 | 5 | [
{
"comment_id": "6208402",
"author": "RetiredHobgoblin",
"timestamp": "2020-01-08T03:21:58",
"content": "“Conventional MRAM requires UP TO 30 layers”. Yes, let’s compare laboratory tech to the most complicated available tech.How about making a fair comparison when counting layers instead of cherry p... | 1,760,373,632.179356 | ||
https://hackaday.com/2020/01/07/fabricated-drum-machine/ | Fabric(ated) Drum Machine | Brian McEvoy | [
"Multitouch Hacks",
"Musical Hacks"
] | [
"arduino",
"conductive thread",
"copper tape",
"drum",
"fabric",
"material",
"midi",
"music",
"sewing",
"soft circuit",
"soft circuits",
"tablerunner"
] | Some folks bring out an heirloom table runner when they have company, but what if you sewed your own and made it musical? We’d never put it away! [kAi CHENG] has an
Instructable about how to recreate his melodic material
, and there is a link to
his website
, which describes his design process, not just the finished product. We have a video below showing a jam session where he exercises a basic function set.
GarageBand is his DAW of choice, which receives translated MIDI from a Lilypad. If you don’t have a Lilypad, any Arduino based on the ATmega328P chip should work seamlessly. Testing shows that conductive threads in the soft circuit results in an occasional short circuit, but copper tape makes a good conductor at the intersections. Wide metallic strips make for tolerant landing pads beneath modular potentiometers fitted with inviting foam knobs. Each twist controls a loop in GarageBand, and there is a pressure-sensitive pad to change the soundset. Of course, since this is all over MIDI, you can customize to your heart’s content.
MIDI drums come in all shapes and sizes, from a
familiar game controller
to
hand rakes
. | 3 | 3 | [
{
"comment_id": "6208645",
"author": "Bean",
"timestamp": "2020-01-08T22:32:37",
"content": "Sounds like BopIt music!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6208683",
"author": "Thomas Chutney",
"timestamp": "2020-01-09T02:29:55",
"content"... | 1,760,373,632.271197 | ||
https://hackaday.com/2020/01/07/liquid-cooling-keeps-this-electronic-loads-mosfets-from-burning/ | Liquid Cooling Keeps This Electronic Load’s MOSFETs From Burning | Dan Maloney | [
"hardware"
] | [
"AIO",
"electronic load",
"heat sink",
"IXTH80N075L2",
"liquid cooling",
"mosfet",
"Thermal"
] | Problem: your electronic load works fine, except for the occasional MOSFET bursting into flames. Solution: do what [tbladykas] did, and
build a water-cooled electronic load
.
One can quibble that perhaps there are other ways to go about preventing your MOSFETs from burning, including changes to the electrical design. But he decided to take a page from [Kerry Wong]’s design book and go big.
[Kerry]’s electronic load
was air-cooled and capable of sinking 100 amps; [tbladykas] only needed 60 or 70 amps or so. Since he had an all-in-one liquid CPU cooler on hand, it was only natural to use that for cooling.
The IXYS linear MOSFET dangles off the end of the controller PCB, where the TO-247 device is soldered directly to the copper cold plate of the AiO cooler. This might seem sketchy as the solder could melt if things got out of hand, but then again drilling and tapping the cold plate could lead to leakage of the thermal coupling fluid. It hasn’t had any rigorous testing yet – his guesstimate is 300 Watts dissipation at this point – but as his primary endpoint was to stop the MOSFET fires, the exact details aren’t that important.
We’ve seen a fair number of liquid-cooled
Raspberry Pis
and
Arduinos
before, but we can’t find an example of a liquid-cooled electronic load. Perhaps [tbladykas] is onto something with this design. | 21 | 8 | [
{
"comment_id": "6208325",
"author": "TJay",
"timestamp": "2020-01-07T21:07:34",
"content": "A good friend of mine has an even less conventional water cooling setup for his load testing. Its 1800watt static load, using 50watt resistors. Bolted to an old aluminum toyota cylinder head, thats sitting i... | 1,760,373,632.961879 | ||
https://hackaday.com/2020/01/07/guitar-hero-controller-gets-a-new-musical-life/ | Guitar Hero Controller Gets A New Musical Life | Lewin Day | [
"Games"
] | [
"guitar hero",
"raspberry pi",
"wii"
] | Guitar Hero
was a big deal, right up until it wasn’t. The best efforts of the video game industry couldn’t resurrect the once-off rush of enthusiasm for rhythm gaming, and thrift stores around the globe are now littered with little plastic instruments. [Analog Sketchbook] decided to give one of these guitars for the Wii a new life,
repurposing it as a synth controller.
The build is a straightforward one, thanks to the prevalence of modern maker solutions to electronic problems. Hooking up to the guitar is a solved problem, with an Adafruit Nunchucky breakout board allowing the Guitar Hero controller to be connected via jumper wires to the Raspberry Pi’s IO pins.
Communication is via I2C, and is easy to work with in Pure Data, running on the Pi. [Analog Sketchbook] created a patch that runs a synthesizer, controlled by the buttons and controls on the guitar itself. With this setup, you could create any number of different routines to allow the guitar to be played differently. We’d love to see a chiptune-esque arpeggio patch, or something that plays fat FM synth tones a la the Genesis, but that’s just our opinion. The sky really is the limit here, with plenty of grunt on the Pi for various forms of synthesis.
It’s a fun build that gives new life to an otherwise forgotten gaming accessory.
We’ve seen them repurposed before too, as far back as 2010
. Video after the break. | 3 | 2 | [
{
"comment_id": "6208505",
"author": "Hal H",
"timestamp": "2020-01-08T13:09:59",
"content": "Wonder if he could have used a Pi Zero W and got it to fit in the controller port where the Wii remote would have gone. I know it says 3B+ / 4 preferred but why? Does he need that much processing to make sy... | 1,760,373,632.551854 | ||
https://hackaday.com/2020/01/07/choosing-the-right-battery-for-your-electric-vehicle-build/ | Choosing The Right Battery For Your Electric Vehicle Build | Lewin Day | [
"Hackaday Columns",
"Transportation Hacks"
] | [
"battery",
"electric vehicle",
"electric vehicles",
"lithium polymer battery"
] | Many a hacker has looked at their scooter, bike, or skateboard, and decided that it would be even better if only it had a motor on it. Setting out to electrify one’s personal transport can be an exciting and productive journey, and one that promises to teach many lessons about mechanical and electronic engineering. Fundamentally, the key to any build is the battery, which has the utmost say in terms of your vehicle’s performance and range. To help out, we’ve prepared a useful guide on selecting the right battery for your needs.
One Chemistry To Rule Them All
Batteries come in all shapes and sizes, and a variety of different chemistries that all have their own unique properties and applications. When it comes to small electric vehicles, it’s desirable to have a battery with a low weight, compact size, plenty of current delivery for quick acceleration, and high capacity for long range.
30 years ago, options were limited to lead acid, nickel cadmium, and nickel metal hydride batteries. These were heavy, with low current output, poor capacity, and incredibly slow charge times. Thankfully, lithium polymer batteries have come along in the meantime and are more capable across the board. Offering huge discharge rates, fast charging, light weight and high capacity, they’re undeniably the ultimate choice for a high performance electric vehicle. They’re also wildly popular, and thus cheap, too!
There are some hangups, however. It’s important to keep all the cells in a pack at the same voltage in order to avoid cells back-charging each other. This can cause damage to the pack, or even explosions or fire. Maintaining the battery voltages to avoid this is called “balancing”. It can be handled in various ways, depending on the exact style of battery you’re using, as we’ll cover later.
Additionally, lithium batteries do not like being over-discharged. As a rule of thumb, it’s a good idea not to let your batteries drop below 3.0 V per cell. Failure to keep this in check can lead to ruining a pack, hurting its maximum capacity and ability to deliver current.
There are thankfully ways around these issues, and which ones you use depends on the battery you choose for your application.
But Which Battery, Exactly?
It’s one thing to say you should use a lithium polymer battery, but they come in a wide variety of flavors for different applications. Which type you use will depend on the vehicle you’re trying to build, your goals for performance and range, and your own abilities and desire to build or buy.
A Word About Voltage and Capacity
Lithium polymer cells are rated nominally at 3.6 V, and their capacity is measured in amp-hours or milliamp-hours. When looking at a pack for your electric vehicle, you’ll want to note the total pack voltage and the capacity. Higher voltages are good for higher performance vehicles and improved efficiency, as more power can be delivered at lower currents with less losses. However, this requires stacking more cells in series, which can add cost, and also requires more expensive controllers and charging solutions. Higher capacities are good for longer range, and are often achieved by stacking more cells in parallel.
Homebrew 18650 Packs
Building your own pack can be a lot of work, but also quite rewarding.
Source: [Adam Bender]
Many home-built electric vehicles are created by hackers with a strong DIY ethos, and that often extends to the individual components, too. In these circles, many elect to create their own battery solution, relying on the popular 18650 cell as the basis for the pack. These can be readily harvested from laptops, power drills and other sources, or picked up from recycling centers, as well as bought new. The cells have a strong metal case and are mechanically quite robust. However, the individual cells are limited to a maximum of around 3600 mAh, despite what you may read on eBay.
Due to the limited capacity of the individual cells, many packs for e-bikes and electric vehicles stack several cells in parallel. 18650-based packs are often referred to with designations like 10S4P, indicating there are 4 parallel sets of 10 cells each in the battery. Such a battery would have a nominal voltage of 36 V, with a capacity of between 10-14 Ah depending on the particular 18650 cells used.
To assemble a pack, soldering is a poor option due to the danger of heating the cells, and the results are typically weak from a mechanical standpoint. The most reliable way is through the use of a spot welder to connect the cells with metal strips from terminal to terminal. Some elect to build their own spotwelders, but if you’re just trying to get your vehicle rolling, this would be considered as
unnecessary yak shaving
. They can be bought instead. Either way, once the cells are connected, individual leads can be added to the various cells for connection to a battery management system, or BMS – a board that monitors the individual voltages of the cells in the pack. This board accepts a connection from a wall charger that sits at the battery’s maximum voltage, and handles charging and balancing to keep the battery in good health, and also protects against over-discharge and over-current events. All this can then be wrapped up in the enclosure of your choice. Thanks to the metal case of the individual cells, often a simple plastic wrap can suffice.
Homebuilt 18650 packs are useful if you want to customise a pack to your own exacting specifications, or if you wish to build on the cheap with recycled parts. However, there’s plenty of work involved, and you may find that the money you spend on tools to get the job done outweighs the savings along the way.
Pros: can be cheap, customizable voltage, capacity and packaging
Cons: significant work involved, can be heavier than other options
eBay E-bike Packs
A typical eBay listing for an eBike battery. Convenient, but current output can be quite limited.
For those uninterested in building their own packs, there is another option. With the proliferation of e-bikes around the world, parts are now readily available to those wishing to strike out on their own. A wide variety of battery packs for e-bikes are now available, most of which are built with the exact same tools and techniques as the homebrew packs mentioned above. The major benefit of these ones, however, is that someone else has done all the hard work!
Consisting of 18650 cells laced together in various configurations to suit different applications, they’re available in a range of voltages from 36 V-60 V and occasionally higher, with large capacities for long range. The vast majority come with an integrated battery management system and a charge connector already hooked up, and many sellers will throw in a suitable wall charger, too.
They’re a great choice if you want a high-capacity pack that’s ready to go, off the shelf, without a lot of fuss. One drawback, however, is that many of these packs are somewhat hobbled from the factory in terms of current output. While the average 18650 is capable of delivering significant current without breaking a sweat, it’s not uncommon to find a 36 V battery limited to a relatively low output of 15 A by the integrated BMS. This is fine if you’re building a 200 watt e-bike to cruise by the beach, but if you’re trying to build a quick scooter to tear along gravel paths with a 500 watt motor, you’re going to run into problems with the BMS cutting the power. This can often be hacked around, but it takes the shine off the convenience of these ready-to-go packs.
Pros: Ready to go, complete solution, fairly robust
Cons: Can have issues with current limits, limited packaging options
RC Flight Packs
High-end RC packs really do look the business, but be sure to handle them carefully!
Lithium polymer batteries have been a boon for the model flight hobby, with their high power density and ability to deliver huge gobs of current at a moment’s notice. These typically use pouch cells, wherein the electrolyte is contained in a plastic pouch without a hard outer shell. These have great packing efficiency and are much lighter than metal cased cells, but are also much more delicate. The cells tend to swell a little over time, and are easy to damage if squeezed or pierced. This can lead to fires or explosion, and thus such cells must be installed in such a way to protect them against accidental damage.
Designed for the demands of high-powered RC aircraft, these cells are capable of current delivery at an immense rate, with 20 times the total battery capacity, or 20C, being common. High-end packs are readily available that can top 75C, which for a 2 Ah pack, is 150 A. This makes these RC packs useful for high-performance applications, where large motors are drawing several kilowatts of power under load. The tradeoff is in storage, with RC packs generally being fairly large for a given capacity, due to the size of the electrodes needed to sustain such high current draws. These packs usually only come as packs of up to 6 cells in series; often you’ll need two or more ganged up to reach a more suitable voltage for your electric vehicle where 10 S to 12 S is usually more desirable.
The high performance packs also come at a high cost, particularly compared to 18650 cells which have the benefits of economies of scale behind them. They also come without any protection or battery management systems. When used in an electric vehicle, they can either be removed after use and hooked up to a standard RC charger, or wired up to a BMS for a more contained solution for charging. Either way, it’s important to pay attention to balancing and maintenance, as these high current packs are more prone to fire and explosions than others.
Pros: Huge current delivery, light weight
Cons: Price, must be handled delicately, needs a charging solution fitted
Power Tool Packs
Often, these packs are a great choice for a quick test build, as you’ve already got them lying around. The connectors can be a pain, though.
Lithium polymer cells have also revolutionized the power tool industry, and made cordless tools far more practical than ever before. Most tools on the market use 18 V, or five-cell packs, with different manufacturers using 18650 cells or pouch cells depending on their tastes. They usually come in a hard plastic case with a proprietary connector to hook up to a certain brand of tools. Inside, there’s usually a basic BMS to handle cell balance and to shut things down if anything goes wrong.
Power tool packs have the benefit of being highly rugged, as they’re designed to withstand the construction environment. Tools can be quite power hungry, so current delivery is usually pretty solid, too. A drawback is that these packs can be quite expensive, because manufacturers want to lock consumers into their own tool ecosystem. Interfacing with them can be a pain too, due to the proprietary connectors. Common workarounds involve nails and tape, 3D printing, or simply gutting old tools. Charging is simply handled by plugging into the standard charger, with the batteries having the benefit of being easily hot-swappable by design. As they’re often already lying around, they can be
a great way to test out an electric vehicle build before investing in a more suitable permanent battery solution.
Pros: Easily hot-swappable, you’ve already got some, rugged
Cons: Expensive, not particularly space efficient, proprietary connectors
Summary
We’re blessed to have more battery options now than ever before, and as capacities and power outputs continue to rise, we continue to see new and more innovative electric vehicles than ever before. By weighing the relevant factors, and choosing carefully, you can pick the optimum solution for the special vehicle in your life. Hopefully, you’ll find this guide useful to point you in the right direction with your own builds, and when you’re done,
be sure to drop us a line! | 43 | 16 | [
{
"comment_id": "6208246",
"author": "Alexander Wikström",
"timestamp": "2020-01-07T18:29:41",
"content": "“however. It’s important to keep all the cells in a pack at the same voltage in order to avoid cells back-charging each other. This can cause damage to the pack,” is actually true for all batte... | 1,760,373,632.851586 | ||
https://hackaday.com/2020/01/07/dmca-locked-tractors-make-decades-old-machines-the-new-hotness/ | DMCA-Locked Tractors Make Decades-Old Machines The New Hotness | Jenny List | [
"News",
"Transportation Hacks"
] | [
"drm",
"farming",
"john deere",
"tractors"
] | It’s fair to say that the hearts and minds of Hackaday readers lie closer to the technology centres of Shenzhen or Silicon Valley than they do to the soybean fields of Minnesota. The common link is the desire to actually own the hardware we buy. Among those working the soil
there has been a surge in demand (and consequently a huge price rise) in 40-year-old tractors
.
Second-hand farm machinery prices have made their way to the pages of Hackaday due to an ongoing battle between farmers and agricultural machinery manufacturers over who has the right to repair and maintain their tractors. The industry giant John Deere in particular uses the DMCA and end-user licensing agreements to keep all maintenance in the hands of their very expensive agents.
It’s a battle we’ve reported on before
, and continues to play out across the farmland of America, this time on the secondary market. Older models continue to deliver the freedom for owners to make repairs themselves, and the relative simplicity of the machines tends to make those repairs less costly overall.
Tractors built in the 1970s and 80s continue to be reliable and have the added perk of predating the digital shackles of the modern era. Aged-but-maintainable machinery is now the sweetheart of farm sales. It confirms a trend I’ve heard of anecdotally for a few years now, that relatively new tractors can be worth less than their older DMCA-free stablemates, and it’s something that I hope will also be noticed in the boardrooms. Perhaps this consumer rebellion can succeed against the DMCA where decades of
activism and lobbying
have evidently failed.
They just don’t build ’em like they used to.
[
Image Source: John Deere 2850
by Raf24 CC-BY-SA 3.0]
[Via
Hacker News
] | 125 | 34 | [
{
"comment_id": "6208187",
"author": "sgraber",
"timestamp": "2020-01-07T16:41:27",
"content": "It’s exactly why I will never own a Deere.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6208199",
"author": "Ostracus",
"timestamp": "2020-01-07... | 1,760,373,632.748453 | ||
https://hackaday.com/2020/01/07/the-oldest-nuclear-reactor-natures-2-billion-year-old-experiment/ | The Oldest Nuclear Reactor? Nature’s 2 Billion Year Old Experiment | Al Williams | [
"Featured",
"Science",
"Slider"
] | [
"fission",
"gabon",
"Nuclear Reactor",
"uranium"
] | When was the first nuclear reactor created? You probably think it was Enrico Fermi’s CP-1 pile built under the bleachers at the University of Chicago in 1942. However, you’d be off by — oh — about 2 billion years.
The first reactors formed naturally about 2 billion years ago in what is now Gabon in West Africa. This required several things coming together: natural uranium deposits, just the right geology in the area, and a certain time in the life of the uranium. This happened 17 different times, and the average output of these natural reactors is estimated at about 100 kilowatts — a far cry from a modern human-created reactor that can reach hundreds or thousands of megawatts.
The reactors operated for about a million years before they spent their fuel. Nuclear waste? Yep, but it is safely contained underground and has been for 2 billion years.
The Basics of Fission Reactors
Any fission reactor basically works the same. An unstable atom like uranium or plutonium breaks apart, creating fast neutrons. There’s a chance some of those neutrons will strike nearby unstable atoms, causing them to break apart too. However, because these neutrons are fast, statistically this won’t happen very often. However, if a moderating substance like water or graphite slows down the neutrons, they have more time to interact with other unstable atoms, so more atoms break down.
If you balance it right, the atoms breaking apart will cause a chain reaction that sustains itself. That is, neutrons hit atoms, releasing more neutrons, which hit more atoms. The heat released is substantial and we usually use it to make steam to drive an electric generator.
Nuclear Fuel Used to Be Much Better
The original CP-1 reactor used natural uranium and so it took a lot of fuel since ordinary uranium is relatively stable. If that uranium is refined into higher concentrations of specific isotopes, a more powerful reaction is possible with less fuel.
There are three isotopes of uranium: U-238, U-235, and U-234. Uranium decays naturally, and highly active isotopes are now in short supply. Apparently, whatever process created the uranium on Earth, it all appeared at the same time (and has been decaying ever since) because no matter where you mine uranium today it is about 99.275% U-238.
U-235 is better for reactors but, today accounts for only 0.72% of what comes out of the ground. We enrich uranium artificially to have about 3% U-235 for use as fuel. Scientists think that when the Earth formed, U-235 was 30% of the crust’s uranium. That number keeps falling, of course, and 2 billion years ago, the proportion would be about 3.6% — just right for nuclear fuel.
When Mined Uranium Came up “Light”
In 1972 a French team mining uranium in Gabon noticed something strange. The ore didn’t have the expected 0.72% of U-235 but instead had 0.717%. That sounds like a tiny bit — and it is — but U-235 content is remarkably consistent all over the world (and on the moon, too). Further investigation confirmed that the missing U-235 was fissioned away in a natural nuclear reactor. In particular, all five fission products you’d expect were located. The amount of Xenon gas trapped in the reactor made it possible to calculate the operating cycle of the reactors.
Eventually, they would find 17 of these natural reactors. You might wonder why there are not even older natural reactors. After all, if 3.6% is a good fuel, wouldn’t 5% or 10% be even better?
The conditions had to be just right. A little over 2 billion years ago, there wasn’t much oxygen in the Earth’s atmosphere and this made it difficult for uranium to concentrate. So to get a natural reactor you need a concentration of uranium that has a high percentage of U-235. There also needs to be a suitable geometry of the material, a moderator like water, and no neutron-absorbing material in the area.
Gabon Geology Oklo
by MesserWoland CC-BY-SA 2.5
You can see in the figure that the uranium ore (3) is surrounded by porous sandstone (2) all on a layer of granite (4). The black zones (1) represent some of the natural fission zones.
Enough water would seep down through the sandstone and cause a reaction that would boil off the water within a half-hour. The reaction would then stop until sufficient water seeped in again creating a 3 hour total cycle time. This allowed the reactors to be very stable and appears to have allowed the reactors to run for about one million years.
There could be more reactors yet to be found or that operated and then did not survive the intervening 2 billion years for us to find. Conditions in Gabon were also just right to preserve the reactors.
Modern Times
If you are worried this could happen today, don’t fret. The U-235 content today is insufficient for this to happen again naturally. However, scientists have studied how waste products have been contained as it might lead to better ways for us to store nuclear waste we are creating.
As an interesting side note, there is
a controversial theory
that the moon was blown out of the Earth about 4.5 billion years ago by another natural reactor near the edge of the Earth’s mantle. While this hasn’t been disproven, as far as we can tell, most scientists seem to accept that the moon formed due to
an impact on the early Earth
. | 34 | 12 | [
{
"comment_id": "6208168",
"author": "Kevin Kessler",
"timestamp": "2020-01-07T15:14:48",
"content": "I just watched a video on this same subject:https://www.youtube.com/watch?v=pMjXAAxgR-MThis professor has a bunch of interesting content if you like to see how our various energy systems works.",
... | 1,760,373,633.217313 | ||
https://hackaday.com/2020/01/06/organic-audio-putting-carrots-as-audio-couplers-to-the-test/ | Organic Audio: Putting Carrots As Audio Couplers To The Test | Jenny List | [
"digital audio hacks",
"Hackaday Columns",
"Lifehacks"
] | [
"audio",
"carrot",
"vegetable"
] | [Boltz999]’s carrot interconnect.
If there’s one thing that gives us joy here at Hackaday it’s a story of audio silliness. There is a rich vein of dubious products aimed at audiophiles which just
beg
to be made fun of, and once in a while we oblige. But sometimes an odd piece of audio equipment emerges with another purpose. Take [Boltz999]’s interconnects for example, which were born of necessity when there were no female-to-female phono adapters to connect a set of cables.
Taking a baby carrot and simply plugging the phonos into its flesh
delivered an audio connectivity solution that worked.
Does this mean that our gold-nanoparticle-plated oxygen-free directional audio cables are junk, and we should be heading for the supermarket to pick up a bag of root vegetables instead? I set out to test this new material in the secret Hackaday audio lab, located on an anonymous 1970s industrial estate in Milton Keynes, UK.
Characterising A Root Vegetable
The high point of an engineer’s life comes as they measure the electrical properties of a root vegetable.
A quick search on
the composition of a carrot
reveals an 88% water content, with the other 12% being mostly carbohydrates, followed by small quantities of fat, protein, and a cocktail of those vitamins and minerals that caused our parents to be so enthusiastic about our younger selves eating them. In particular about 0.4% of a carrot is comprised of potassium, sodium, and calcium ions in solution, making the vegetable analagous to a sponge soaked in a weak electrolyte solution. Thus you’d expect it to be conductive, and to pass a line-level audio signal into a high-impedance load such as an audio amplifier. A quick DC resistance measurement of our test carrot showed a resistance that started at about 50K for distances up to about 10mm, rising slowly to near 100K across its roughly 80mm length. It’s probably beyond the scope of this piece, to characterise the complex impedance of a carrot.
Attenuator Π-section circuit by SpinningSpark
CC-BY-SA 3.0. R2 represents the width of the carrot, R1 and R3 each represent the carrot distance between pin and outer of a phono plug.
The hack that prompted all this though didn’t simply replace the pair of copper wires with ones made of carrot. By plugging the phono into the tap root an extra 50K resistance is created between its two conductors as well as between it and the other phono, and the result is a resistor network. Because it’s not an unreasonable assumption the two pieces of hi-fi equipment in the same rack could share an earth, rather than disappear down the rabbit hole of infinite meshes of resistors it’s probably safe instead to think of it as something closer to the familiar
Pi network attenuator
. There are plenty of online calculators that could give you a performance figure for a given network, but in this case with so many approximations and carrot-related guesses their results would be rather meaningless. All that we need to know is that there will be some attenuation of any audio fed into the carrot.
Crisp Treble, and a Crunchy Midrange
The square wave performance of a carrot
Having discussed the theory, it’s time to move onto the practice. Standing in for a high-end audio source was my phone playing YouTube videos, and for a high-end hi-fi a set of amplified computer speakers. Surprisingly it worked, but unsurprisingly in doing so there was a noticeable attenuation that cut the volume by around half. Exactly as expected, but there was a further step of taking a look at it with a ‘scope.
Applying a handy 1kHz squarewave a 30% attenuation was immediately obvious (as well as that maybe the secret lab’s ‘scope probes needed adjusting). We lacked an audio analyser to measure the harmonic distortion of the coupling, but there has to come a point at which characterising a vegetable comes to an end.
So, we’ve proved the original story to be true, you can use a carrot in an audio interconnect. But how would we describe its
sound
? The answer if you are fond of audiophile reviews is that it adds an organic feel to the broader soundstage, with crisp treble notes, a crunchy midrange, and deep, earthy bass tones. Meanwhile if you are simply looking for something to connect two cables, we’d suggest a carrot sounds better in the roasting pan.
Header image: Sajetpa [
CC BY-SA 3.0
] | 34 | 13 | [
{
"comment_id": "6207970",
"author": "Lee Studley",
"timestamp": "2020-01-06T18:21:42",
"content": "Is it April 1st already?",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6207981",
"author": "Ren",
"timestamp": "2020-01-06T19:13:02",
... | 1,760,373,633.043038 | ||
https://hackaday.com/2020/01/06/3d-printed-tools-turn-bench-vise-into-expedient-press-brake/ | 3D-Printed Tools Turn Bench Vise Into Expedient Press Brake | Dan Maloney | [
"Tool Hacks"
] | [
"bench vise",
"bending",
"die",
"Machine tool",
"PETG",
"PLA",
"press brake",
"punch",
"reinforced",
"sheet metal"
] | Chances are pretty good that most of us have used a bench vise to do things far beyond its intended use. That’s understandable, as the vise may be the most powerful hand tool in many shops, capable of exerting tons of pressure with the twist of your wrist. Not taking advantage of that power wouldn’t make any sense, would it?
Still, the clamping power of the vise could sometimes use a little finesse, which is the thinking behind
these 3D-printed press brake tools
. [Brauns CNC] came up with these tools, which consist of a punch and a die with mating profiles. Mounted to the jaws of the vise with magnetic flanges, the punch is driven into the die using the vise, forming neat bends in the metal. [Braun] goes into useful detail on punch geometry and managing springback of the workpiece, and handling workpieces wider than the vise jaws. The tools are printed in standard PLA or PETG and are plenty strong, although he does mention using
his steel-reinforced 3D-printing method
for gooseneck punches and other tools that might need reinforcement. We’d imagine
carbon-fiber reinforced filament
would add to the strength as well.
To be sure, no matter what tooling you throw at it, a bench vise is a poor substitute for a real press brake. Such machine tools are capable of working sheet metal and other stock into intricate shapes with as few setups as possible, and bring a level of power and precision that can’t be matched by an improvised setup. But the ability to make small bends in lighter materials with homemade tooling and elbow grease is a powerful tool in itself.
Thanks to [Keith Fulkerson] for the tip. | 33 | 13 | [
{
"comment_id": "6207947",
"author": "Capt McAllister",
"timestamp": "2020-01-06T16:45:19",
"content": "I could be wrong, but it feels like it would have been just as easy to clamp the thin sheet metal shown in the vise and bend it with your bare hands. Thicker sheet metal could be bent with a rubb... | 1,760,373,633.301452 | ||
https://hackaday.com/2020/01/06/continuous-integration-what-it-is-and-why-you-need-it/ | Continuous Integration: What It Is And Why You Need It | Ben James | [
"Featured",
"Original Art",
"Slider",
"Software Development"
] | [
"build",
"cd",
"ci",
"continuous deployment",
"continuous integration",
"deploy",
"flask",
"gitlab",
"heroku",
"introduction",
"pipeline",
"pylint",
"pytest",
"static analysis",
"tdd",
"test"
] | If you write software, chances are you’ve come across Continuous Integration, or CI. You might never have heard of it – but you wonder what all the ticks, badges and mysterious status icons are on open-source repositories you find online. You might hear friends waxing lyrical about the merits of CI, or grumbling about how their pipeline has broken again.
Want to know what all the fuss is about? This article will explain the basic concepts of CI, but will focus on an example, since that’s the best way to understand it. Let’s dive in.
What is CI anyway?
The precise definition of Continuous Integration refers to the practice of software developers frequently checking in their code, usually multiple times a day in a commercial setting, to a central repository. When the code is checked in, automated tests and builds are run, to verify the small changes which have been made. This is in preference to working on a ginormous slab of code for a week, checking it in, and finding out it fails a large number of tests, and breaks other people’s code.
Whilst this is a valid definition, colloquially CI has become synonymous with the automation part of this process; when people refer to CI, they are often referring to the tests, builds, and code coverage reports which run automatically on check-in.
Additionally, CI is often lumped together with its sister, Continuous Deployment (CD). CD is the practice of deploying your application automatically: as soon as your code has been pushed to the correct branch and tests have passed. We’ll talk more about this soon.
Case study – a simple API
I’m going to save any more explanation or discussion of the merits of CI until after we’ve seen an example, because this will make it easier to picture what’s going on.
The aim of this example is to make a very simple Python application, then use CI to automatically test it, and CD to automatically deploy it. We’re going to use GitLab CI, because it’s a neat, integrated solution that is easy to setup. You can view the finished repository containing all the files
here
.
Let’s start by creating a Python file containing our main application logic. In this case, it’s some string processing functions.
""" web/logic.py. Contains main application code. """
def capitalise(input_str):
"""Return upper case version of string."""
return input_str.upper()
def reverse(input_str):
"""Return reversed string."""
return input_str[::-1]
Let’s also add some extremely basic tests for this code:
""" test_logic.py. Tests for main application code. """
from web import logic
def test_capitalise():
"""Test the `capitalise` function logic."""
assert logic.capitalise("hackaday") == "HACKADAY"
def test_reverse():
"""Test the `reverse` function logic."""
assert logic.reverse("fresh hacks") == "skcah hserf"
assert logic.reverse("racecar") == "racecar"
Ok, now that we’ve made our main application code, let’s expose it over an API. We’ll use Flask for this. Don’t worry about meticulously reading this, it’s just here to serve as an example, and is shown here for context.
""" web/api.py. Expose logic functions as API using Flask. """
from flask import Flask, jsonify
import web.logic as logic
app = Flask(__name__)
@app.route('/api/capitalise/<string:input_str>', methods=['GET'])
def capitalise(input_str):
""" Return capitalised version of string. """
return jsonify({'result': logic.capitalise(input_str)})
@app.route('/api/reverse/<string:input_str>', methods=['GET'])
def reverse(input_str):
""" Return reversed string. """
return jsonify({'result': logic.reverse(input_str)})
if __name__ == '__main__':
app.run()
Note that we should test the API as well (and Flask has some nice ways to do this), but for conciseness, we won’t do this here.
Now that we have an example application setup, let’s do the part we’re all here for and add a CI/CD pipeline to GitLab. We do this by simply adding a
.gitlab-ci.yml
file to the repository.
In this explanation we’re going to walk through the file section by section, but you can view the full file
here
. Here’s the first few lines:
image: python:3
stages:
- analyse
- test
- deploy
This sets the default Docker image to run jobs in (Python 3 in this case), and defines the three stages of our pipeline. By default, each stage will only run once the previous stage has passed.
pylint:
stage: analyse
script:
- pip install -r requirements.txt
- pylint web/ test_logic.py
This is the job for our first stage. We run
pylint
as an initial static analyser on the code to ensure correct code formatting and style. This is a useful way to enforce a style guide and statically check for errors.
pytest:
stage: test
script:
- pip install -r requirements.txt
- pytest
This is our second stage, where we run the tests we wrote earlier, using
pytest
. If they pass, we continue to our final stage: deployment.
staging:
stage: deploy
script:
- apt-get update -qy && apt-get install -y ruby-dev
- gem install dpl
- dpl --provider=heroku --app=hackaday-ci-staging --api-key=$HEROKU_API_KEY
production:
stage: deploy
only:
- master
script:
- apt-get update -qy && apt-get install -y ruby-dev
- gem install dpl
- dpl --provider=heroku --app=hackaday-ci-prod --api-key=$HEROKU_API_KEY
Our aim here is to deploy the API onto some kind of server, so I’ve used Heroku as the platform, authorised with an API key.
This last stage is slightly different from the others because it contains two jobs that deploy to two places: staging and production. Note that we deploy to staging on any commit, but we only deploy to production when we push to or merge into master. This means that we can check, test and use our live app in staging after any code change, but the production app isn’t affected until our code is merged into master. (In a larger project, it often makes more sense to deploy to staging on master and only deploy to production when a commit is tagged.)
And that’s it! In less than 40 lines we’ve defined a completely automated system to check and deploy our code. We are rewarded by our pipeline showing up in GitLab as below:
Additionally, the
.gitlab-ci.yml
configuration file which specifies what to automate is usually also version-controlled, so that if the CI pipeline evolves, it evolves alongside the relevant version of your code.
Why it’s useful
All manner of tasks can be automated using CI, and can allow you to catch errors early and fix them before they propagate technical debt in the codebase.
Common tasks for larger Python projects might be to test our code for compatibility with different Python versions, build a Python module as a wheel, and/or push it to PyPi. For projects using compiled languages, you could automatically build your binaries for all your target platforms. For web development, it’s easy to see the benefit of automatically deploying new code on a server once certain conditions have been met.
Furthermore, part of the reason that CI is so powerful is its close relation to version control. Every time that code is pushed to any branch in a repository, tests and analysis can run, which means that people who control master or protected branches can easily see if code is safe to merge in.
Indeed, whilst CI is most satisfying when the pipeline is full of ticks, it is most useful when it looks like this:
This means that the tests failed, and as a result, the broken code was not deployed. People can clearly see not to merge this code into important branches.
Conclusions: do you need CI?
CI/CD is definitely more useful in some cases than others. But if you’re writing any code at all, you can save yourself time by writing tests for it. And if you have tests, why not run them automatically on every commit?
I can personally say that every time I’ve set up a CI pipeline, not only has it saved me time, but at some point or another it got me out of a scrape by catching broken code. I’d wager it will do the same for you. | 35 | 10 | [
{
"comment_id": "6207932",
"author": "drenehtsral",
"timestamp": "2020-01-06T15:57:20",
"content": "Like any software development methodology, CI/CD works well when applied thoughtfully to suitable problems (high-level APIs and mature code bases where changes are likely to be incremental and other t... | 1,760,373,633.38559 | ||
https://hackaday.com/2020/01/06/hackaday-belgrade-call-for-proposals/ | Hackaday Belgrade: Call For Proposals | Mike Szczys | [
"cons",
"Featured"
] | [
"2020 Hackaday Belgrade",
"call for proposals"
] | Join Hackaday in Belgrade, Serbia on May 9th, 2020 for the Hackaday Belgrade conference! The biennial hardware conference is just seventeen weeks from now. Early Bird tickets will go on sale shortly, but beginning right now you can hack your way into the conference by
submitting a talk proposal
. Accepted speakers receive free admission, plus everyone who submits a quality talk proposal will be given priority when tickets go on sale.
Yes, I’m talking to you. Hackaday strives to include first-time speakers in the slate of presenters at our conferences. We’re looking for unique, cutting-edge, whimsical, crazy, formidable, or world-changing topics revolving around hardware creation. From learning new tools or techniques to fabrication adventures, from code-wrangling that firmware project to pulling off an art installation, and from forgotten hardware history to the impossible made possible on your own workbench, we need to hear your stories!
That project for which you went into the deep weeds and worked your way back out again? Everyone at a Hackaday conference wants to hear about it and in the greatest detail possible. After all, we’re your fellow hackers. In fact, you should probably bring the hardware along for the ride.
We Need You
None of this happens in a vacuum. This is the third Hackaday Belgrade conference, which have now settled into a tick-tock cadence of even-numbered years. The first two both sold out, this one will as well, and the result is always
an action-packed, nearly 24-hour marathon sprint
of talks, workshops, and hardware hacking. But the only reason this works is because amazing people just like you make it a priority in their life to be there.
Badge hacking at 2018 Hackaday Belgrade
So take the plunge,
put together your talk proposal and submit it before March 2nd
. But don’t stop there, pester your friends and your heros to do the same. Block out May 9th on your schedule (roughly 9 am-2 am) and take the day before off of work. While you’re at it, convince your boss and coworkers to come along with you. See you in Belgrade! | 3 | 3 | [
{
"comment_id": "6207921",
"author": "Telimektar",
"timestamp": "2020-01-06T15:42:47",
"content": "Oh GODS, again in Belgrade. Great things happen again!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6207931",
"author": "MvK",
"timestamp": "2020-01-06... | 1,760,373,632.903262 | ||
https://hackaday.com/2020/01/06/steampunk-motorcycle-runs-on-compressed-air-is-pure-hacking-art/ | Steampunk Motorcycle Runs On Compressed Air, Is Pure Hacking Art | Danie Conradie | [
"Art",
"Transportation Hacks"
] | [
"art",
"compressed air engine",
"motorcycle",
"steampunk"
] | Sometimes it’s ok to sacrifice some practicality for aesthetics, especially for passion projects. Falling solidly in this category is [Peter Forsberg]’s beautiful, barely functional
steam punk motorcycle
. If this isn’t hacker art, then we don’t know what is.
The most eye-catching part of the motorcycle is the engine and drive train, with most of the mechanical components visible. The cylinders are clear glass tubes with custom pistons, seals, valves and push rods. The crank mechanism is from an old Harley and is mounted inside a piece of stainless steel pipe. Because it runs on compressed air it cools down instead of heating up, so an oil system is not needed.
For steering, the entire front of the bike swings side to side on hinges in the middle of the frame, which is quite tricky to ride with a top speed that’s just above walking speed. It can run for about 3-5 minutes on a tank, so the [Peter] mounted a big three-minute hour glass in the frame. The engine is fed from an external air tank, which he wears on his back; he admits it’s borderline torture to carry the thing for any length of time. He plans to build a side-car to house a much larger tank to extend range and improve riding comfort.
[Peter] admits that it isn’t very good as a motorcycle, but the amount of creativity and resourcefulness required to make it functional at all is the mark of a true mechanical hacker. We look forward to seeing it in its final form.
For more inspiration check out the
DIY electric motorcycle
, and the
flying motorcycle
that the Dubai police is testing. | 27 | 10 | [
{
"comment_id": "6207889",
"author": "Alexander Wikström",
"timestamp": "2020-01-06T12:42:16",
"content": "A truly interesting project, and rather impressive craftsmanship too.Though, the engine could need some minor improvements, it seems a bit jerky to say the least…Adding a flywheel could smooth ... | 1,760,373,633.447881 | ||
https://hackaday.com/2020/01/06/embedding-a-smart-switch-in-a-java-factory/ | Embedding A Smart Switch In A Java Factory | Kristina Panos | [
"how-to",
"Misc Hacks"
] | [
"coffee machine",
"extra heet",
"home automation",
"Moccamaster",
"z-wave"
] | When you need coffee, you don’t need any hassles standing between you and caffeination. Especially ironic hassles, like having to do more to turn on appliances inside of home automation schemes than you did without them.
[Maurice Makaay] bought a smart plug to add this beautiful drip coffee machine to his Z-Wave setup, but it isn’t all that smart. Starting the brew remotely means making sure that both the machine’s power switch and the smart plug switch are on. Some members of the household still like making their coffee the old-fashioned way, so [Maurice] came up with a smart, single switch solution to satisfy both cases.
The answer comes in the form of a Z-Wave switch that takes dual inputs and is small enough to fit inside the machine
. After a lot of searching around for compatible, splash-proof parts, [Maurice] replaced the existing on/off rocker with a momentary rocker for making coffee manually. That switch labeled ‘extra heet’ used to turn the warming burner on and off. Since he never uses the burner, the switch receptacle now houses a power indicator light.
[Maurice] went about this mains appliance hack the right way — he used extra thick wires connected with lever nuts, and kept the machine’s
equally beautiful spare parts and safety documentation
by his side the whole time. A person could probably become a lot more comfortable with the idea of installing these by looking over [Maurice]’s pictures of the process.
You know how coffee makes everything better? Turns out ‘everything’ includes
printer filament
. | 3 | 3 | [
{
"comment_id": "6207874",
"author": "Ge07",
"timestamp": "2020-01-06T10:45:25",
"content": "This coffee maker is the best I ever used, congrats for the hack",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6207875",
"author": "wibble",
"timestamp": "202... | 1,760,373,633.488541 | ||
https://hackaday.com/2020/01/05/creating-a-custom-engagement-ring-with-3d-printing/ | Creating A Custom Engagement Ring With 3D-Printing | Dan Maloney | [
"Misc Hacks"
] | [
"casting",
"diamond",
"gold",
"jewelry",
"lost wax",
"ring",
"shapeways",
"sla"
] | Even if you’re pretty sure what the answer will be, a marriage proposal is attended by a great deal of stress to make the event as memorable and romantic as possible. You’ve got a lot of details to look after, not least of which is the ring. So why not take some of the pressure off and just 3D-print the thing?
No, a cheesy PLA ring is probably not going to cut it with even the most understanding of fiancees, and that’s not at all what [Justin Lam] did with
this DIY engagement ring
. He took an engineer’s approach to the problem – gathering specs, making iterative design changes in Fusion 360, and having a prototype ring SLA printed by a friend. That allowed him to tweak the design before sending it off to Shapeways for production. We were surprised to learn that jewelry printing is a big deal, and Shapeways uses a lost-wax process for it. First a high-resolution wax SLA printer is used to make a detailed positive, which is then used to make a plaster mold. The mold is fired to melt the wax, and molten gold is poured in to make the rough casting, which is cleaned and polished before shipping.
Once he had the ring, [Justin] watched a few jewelry-making videos to learn how to set the family heirloom stone into the bezel setting; we admit we cringed a bit when he said he used the
blade
shaft of a screwdriver to crimp the edge of the bezel to the stone. But it came out great, even if it needed a bit of resizing. The details of the proposal are left to the romantically inclined, but TL;DR – she said yes.
Congratulations to the happy couple, and to [Justin] for pulling off a beautiful build. Most of our jewelry hacks are of
the blinkenlight variety
rather than fine jewelry, although we have featured
a machinist’s take on the subject
before. | 11 | 9 | [
{
"comment_id": "6207856",
"author": "mime",
"timestamp": "2020-01-06T06:59:14",
"content": "nice! Engagement and wedding rings are ridiculously overpriced, especially if you want something made custom.",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6207865",
... | 1,760,373,633.55629 | ||
https://hackaday.com/2020/01/04/2d-platform-seeks-balance-with-a-touch-screen/ | 2D-Platform Seeks Balance With A Touch Screen | Dan Maloney | [
"Microcontrollers",
"Robots Hacks"
] | [
"control loop",
"feedback",
"pic32",
"pid",
"resistive",
"servo",
"touch screen"
] | It’s the [Bruce Land]-iest season of all, when the Cornell professor submits the projects his microcontroller class students have been working on all semester. Imagination does not seem to be in short supply with these students, and we always look forward to these tips this time of year.
[Greg] and [Sam]’s
touch-screen two-dimensional ball balancer
is a good example of what [Land]’s students turn out. The resistive touch screen is supported by a 3D-printed gimballed platform and tilted in two axes by hobby servos. [Greg] and [Sam] chose to read the voltage outputs from the touch screen directly using the ADC on a PIC32, toggling between the two axes at 2 kHz. Two PID control loops were implemented to keep the ball as centered as possible on the platform, and the video below shows that there’s still some loop tuning to do. But given the positional inaccuracies of hobby servos and the compliance in the gimbal, we’re impressed that they were able to keep the system under control at all.
Of course we’ve seen ball-balancers before, but most of them have closed the loop using either
cameras
or
microphones
. Seeing direct sensing on the platform like this is a nice change of pace. | 17 | 8 | [
{
"comment_id": "6207679",
"author": "Flemming",
"timestamp": "2020-01-05T09:48:49",
"content": "Nice, though it bothers me immensely that the psu goes into constant current mode, it might even be contributing to the instability.",
"parent_id": null,
"depth": 1,
"replies": []
},
{
... | 1,760,373,633.766207 | ||
https://hackaday.com/2020/01/04/3d-printed-moire-illusion-may-just-drive-you-crazy/ | 3D-Printed Moiré Illusion May Just Drive You Crazy | Lewin Day | [
"Art"
] | [
"moire",
"moire pattern",
"moire patterns"
] | Moiré illusions can be visually captivating, particularly when a little rotational motion is thrown in the mix. [Dushyant Ahuja] was a fan of these moving Moiré sculptures he’d seen around the place,
and decided to create his own.
The build is based around spinning two spoked discs in opposite directions, such that the spokes create moving Moiré patterns as they turn. To achieve this, the discs were 3D printed, along with a central housing containing two 12 volt gear motors. 3D printed gears are used to allow both discs to rotate about the same axis. Nominally, the motors spin relatively slowly, generating a pleasing, hypnotic effect when turning the discs.
The drivetrain is under the control of an ESP8266, though [Dushyant] notes that to get the basic effect, one need only connect the motors to a 12 volt power supply and let them run. However, future plans involve adding some LEDs for bling, and varying the motor speed to create yet more complex effects. With the microcontroller already installed, upgrades should be a cinch.
Moiré effects are good for everything from
guiding ships
to
taking precision measurements.
If you’ve found a new application for these confounding line patterns,
be sure to let us know!
Video after the break. | 20 | 10 | [
{
"comment_id": "6207649",
"author": "Edward Simpson",
"timestamp": "2020-01-05T03:22:56",
"content": "Seriously? That project has been bouncing around the net for the last 6 months or so, think it was on Instructables last I checked.",
"parent_id": null,
"depth": 1,
"replies": [
{... | 1,760,373,633.819594 | ||
https://hackaday.com/2020/01/04/babys-first-jukebox-is-fun-for-parents-too/ | Baby’s First Jukebox Is Fun For Parents, Too | Kristina Panos | [
"Arduino Hacks",
"Musical Hacks"
] | [
"arduino",
"god mode",
"mp3 player",
"music maker shield",
"toddlers"
] | Believe it or not, there’s a $400 toy mp3 player out there for kids. It looks pretty nice, with colorful buttons and a wood console and all, but those features don’t really justify the price tag. [DerThes] wanted one for his 2-year-old anyway, so
he made his own ruggedized version
for a whole lot less.
The simple and kid-friendly interface lets [DerThes Jr.] choose from one of nine albums to play by pushing one of the candy-colored buttons. The bottom row of buttons handle play/pause and moving through the track list. When mom and dad get tired of listening to whatever the kids are into these days, they can enter the special god mode code to access 99 of their favorite albums.
This baby boombox is built with an Arduino Uno and an Adafruit music maker shield. [DerThes] etched his own PCB to hold the buttons and the pair of shift registers needed to interface them with the Uno. If you’ve never etched before, here’s a good chance to dip your toe in the ferric chloride, because [DerThes] has the transparency in
his repo
and a line on a nice instructional video.
If you don’t think your toddler is ready to respect a field of momentaries,
you could make a jukebox with NFC blocks
.
[via
Arduino blog
] | 12 | 7 | [
{
"comment_id": "6207608",
"author": "Stuart Longland",
"timestamp": "2020-01-05T00:40:37",
"content": "> here’s a good chance to dip your toe in the ferric chlorideErrm, I wouldn’t be dipping *any* body part in the ferric chloride… Not unprotected anyway. That stuff eats copper for breakfast!",
... | 1,760,373,633.714207 | ||
https://hackaday.com/2020/01/04/datacenter-ups-heads-home-for-off-grid-power-solution/ | Datacenter UPS Heads Home For Off-Grid Power Solution | Jenny List | [
"home hacks",
"News"
] | [
"battery backup",
"lead acid battery",
"off grid"
] | The news sites seem never to be without stories of Elon Musk and his latest ventures, be they rapid transit tube tubes in partial vacuum, space flight, or even personal not-a-flamethrowers. Famous for electric vehicles, Musks’s Tesla also has a line of solar products and offers the Powerwall home battery power system. These are tantalizing to anyone with solar panels, but the price tag for one isn’t exactly a dream.
[Nathann]’s budget couldn’t stretch to a Powerwall, but he did have access to a hefty ex-datacentre uninterruptible power supply (UPS) and a large quantity of lead-acid cells. From this he built his own
off-the-grid power in the cellar of the home
. It’s not as elegant as a Powerwall, but it can power the house on moderate usage, so he claims, for up to ten days.
On one level the installation is more of a wiring job than one of high technology, but the logistics of dealing with nearly 100 lead-acid cells are quite taxing. The UPS takes four battery packs, each clocking in at 288 V. The cells are joined with copper straps, and the voltage and current involved is not for the faint-hearted. An accidental short vaporized a screw and a battery terminal; if this were our house we’d put fuses in the middle of the battery packs.
The batteries are stored on wooden pallets atop brick pillars in case the cellar floods. The basement installation now is ready for the addition of solar and wind-based off-grid sources. Maybe your battery power solution will be less hair-raising, but it’s unlikely to be cheaper. Meanwhile this isn’t the first such project we’ve seen, though
others usually go for 18650 Li-Ion cells
, the use of lead acid remains a viable and economical solution. | 63 | 16 | [
{
"comment_id": "6207566",
"author": "RW ver 0.0.1",
"timestamp": "2020-01-04T21:13:10",
"content": "Also make sure Mr Robot doesn’t hack ur firmware.",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6207570",
"author": "Luke",
"timestamp": "2020-01-04T2... | 1,760,373,633.921328 | ||
https://hackaday.com/2020/01/04/altair-8800-again-project/ | Altair 8800 Again Project | Al Williams | [
"Retrocomputing"
] | [
"altair",
"Teensy"
] | [Dirk] posted a video (you can see below) titled, “Mystery Retro Project Start.” That turned out to be the first of a multipart series on his Altair 8800 Again simulator. The front panel appears to be laser cut and in some
future video episodes
, we expect to see him simulate the CPU with a Teensy.
There have been plenty of 8800 clones ranging from projects that recreate the original PCBs, to those that just run a Raspberry Pi inside. The middle ground will use an Arduino or some other small CPU to simulate the 8080 CPU.
The switches are multiplexed which isn’t uncommon. However, the LEDs are actually an addressable LED strip. We’ve built a similar panel with discrete LEDs and we can attest that using the strip is going to be easier. Besides that, it allows you to change the LED color to suit your decor, something the old 8800 could not do without a soldering iron.
The downside, of course, is that you can update the LEDs at exactly the same time. For most things that’s probably not going to matter much, but it is still a little bit of a departure from the original computer.
Even without emulation, this would be a good start for a panel to connect to SIMH running on a PC. The use of the LED strips and the laser cutter make this a lot easier than most other builds we’ve seen.
We always think about the Altair around the end of the year since the original showed up in the
January 1975 edition of Popular Electronics
(which would be on newsstands in December).
If you don’t have the patience to build a full front panel, you can
put it on a PCB
instead. In fact, we’d be tempted to build a series of PCBs to mount behind the panel. We’ve seen that approach
a few times before
. | 6 | 2 | [
{
"comment_id": "6207527",
"author": "Doc Oct",
"timestamp": "2020-01-04T18:08:22",
"content": "I’m surprised nobody has taken those 3 cent MCUs that were talked about previously and made addressable controls yet.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id"... | 1,760,373,633.964045 | ||
https://hackaday.com/2020/01/04/city-clock-is-beautiful-tribute-to-parisian-architecture/ | City Clock Is Beautiful Tribute To Parisian Architecture | Lewin Day | [
"clock hacks"
] | [
"binary clock",
"clock"
] | Binary clocks are often created as a programming exercise, or to display the time in a project with the minimal practical components. Displaying the time in binary needn’t always be for practicalities sake, however.
The City Clock shows that it can be applied quite artfully, too
.
The electronic side of things is simple – an Arduino Nano runs 13 LEDs, with a digital IO pin for each. Including a real time clock module is optional, though we imagine pretty essential if you wish the clock to keep accurate time. The LEDs are fitted into a grid, which is fitted behind the windowed facade of the building. This helps block light leaks between adjacent segments, giving a more polished look to the final design. The whole assembly is built out of lasercut wood, making it a quick and easy build if you’ve got such a tool handy.
It’s a simple concept, but one that is particularly striking in action. Even to those unaware of its horological abilities, it presents the appearance of a living building, with inhabitants switching lights on and off throughout the day. It would make an excellent bookshelf or coffee table piece, and we’re highly tempted to give building our own a go. Video after the break. | 9 | 8 | [
{
"comment_id": "6207499",
"author": "DainBramage",
"timestamp": "2020-01-04T15:33:08",
"content": "I’m not usually a fan of binary clocks, but this one is actually pretty cool!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6207514",
"author": "RoGeorge",... | 1,760,373,634.045373 | ||
https://hackaday.com/2020/01/04/opendog-adding-force-sensitive-feet/ | OpenDog: Adding Force Sensitive Feet | Danie Conradie | [
"Robots Hacks"
] | [
"3d printing",
"actuators",
"close",
"OpenDog",
"pwm",
"robotics"
] | [James Bruton] OpenDog remains one of the most impressive home-built robotics projects we’ve seen here on Hackaday, and it’s a gift that just keeps on giving. This time he’s working on adding
force sensing capabilities
to OpenDog’s legs to allow for more dynamic movement control.
The actuators in the legs are three-phase outrunner motors that drive ball-screws via a belt. This configuration is non-backdrivable, meaning the legs cannot be moved when an external force is, which could lead to mechanical failures. He as tested other backdrivable leg configurations with
other robots
, but did not want to rebuild OpenDog completely. The solution [James] went with is a redesigned foot with an inbuilt switch, to confirm that the foot is touching the ground, and a load cell attached in the middle of the bottom leg segment. The load cell is bolted rigidly onto the leg segment, which allows it to sense when the leg is carrying load, without damaging the load cell itself.
Unfortunately all the serial ports on OpenDog’s main Teensy 3.6 controller are already used, so he converted the signal from the load cell to PWM, to allow it to be read by a normal GPIO pin. This works well in isolation, but when [James] switches on the motors, the PWM signal from the load sensor gets flooded by interference, making it unreadable. To solve this problem, he wants to implement a CAN bus, which will allow for more inputs and outputs and hopefully solve the interference problem. However, [James] has no experience with the CAN protocol, so learning to use it is going to be a project on its own.
OpenDog
is turning into a very lengthy, time-consuming project, [James] says that the lessons learned from it have been invaluable for a number of other projects. This is something to keep in mind with everything we tackle. Choose projects were the experience gained and/or relationships developed are worth it on their own, even when the project fails in a conventional sense. This way you can never really lose. | 16 | 6 | [
{
"comment_id": "6207470",
"author": "deshipu",
"timestamp": "2020-01-04T12:37:05",
"content": "It’s an impressive tour de force of robot design, a proof that anything can work if you only install enough Arduinos in it.",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment... | 1,760,373,634.102199 | ||
https://hackaday.com/2020/01/05/airbass-lets-you-jam-wherever/ | AirBass Lets You Jam Wherever | Kristina Panos | [
"Microcontrollers",
"Musical Hacks"
] | [
"bass guitar",
"break-beam detector",
"bruce land",
"pic32"
] | If you play an instrument, you know how rewarding it is to watch and hear yourself reproduce your favorite songs and make new melodies. But you also know how steep the learning curve can be, how difficult it is to learn positions and notes while your body adjusts to the physical side. For stringed instruments, that means gaining muscle memory, growing fingertip calluses, and getting used to awkward arm positions.
For their final project in [Bruce Land]’s class on designing with microcontrollers,
[Caitlin, Jackson, and Peter] decided to make a more accessible bass guitar
. For starters, it can be placed flat on a table similar to a pedal steel guitar to get around those awkward arm positions. Instead of plucking or slapping the strings, the player wears a glove with a flex resistor on each finger, and plays the string by curling and uncurling their finger.
We think the team’s implementation of the left hand duties and fretboard is pretty clever. Each of the four strings has a break-beam detection circuit, and a single distance sensor decides where the finger is along the fretboard. Another great thing about this backpack-sized bass is that it never needs tuning. If you stay tuned, you can hear [Peter] play “Smoke On the Water” after the break.
There’s more than one way to make an air guitar —
this one that does it with LIDAR
. | 11 | 6 | [
{
"comment_id": "6207851",
"author": "Benjamin Scherrey",
"timestamp": "2020-01-06T05:54:24",
"content": "Good example of a project that would have benefited by working with a domain expert (i.e. bass player) before jumping too far into the implementation. The design prohibits any common right hand ... | 1,760,373,634.157009 | ||
https://hackaday.com/2020/01/05/hackaday-links-january-5-2020/ | Hackaday Links: January 5, 2020 | Dan Maloney | [
"Hackaday Columns",
"Hackaday links"
] | [
"colorado",
"data recovery",
"drone",
"hackaday links",
"hard drive",
"laser",
"magnet",
"medical imaging",
"mobility",
"non-contact",
"search",
"segway",
"self balancing",
"uav",
"ultrasound"
] | It looks like the third decade of the 21st century is off to a bit of a weird start, at least in the middle of the United States. There, for the past several weeks,
mysterious squads of multicopters
have taken to the night sky for reasons unknown. Witnesses on the ground report seeing both solo aircraft and packs of them, mostly just hovering in the night sky. In mid-December when the nightly airshow started, the drones seemed to be moving in a grid-search pattern, but that seems to have changed since then. These are not racing drones, nor are they DJI Mavics; witnesses report them to be 6′ (2 meters) in diameter and capable of staying aloft for 90 minutes. These are serious professional machines, not kiddies on a lark. So far, none of the usual government entities have taken responsibility for the flights, so speculation is all anyone has as to their nature. We’d like to imagine someone from our community will get out there with radio direction finding gear to locate the operators and get some answers.
We all know that water and electricity don’t mix terribly well, but thanks to the seminal work of
White, Pinkman
et al
(2009)
, we also know that magnets and hard drives are a bad combination. But that didn’t stop Luigo Rizzo from
using a magnet to recover data from a hard drive
. He reports that the SATA drive had been in continuous use for more than 11 years when it failed to recover after a power outage. The spindle would turn but the heads wouldn’t move, despite several rounds of percussive maintenance. Reasoning that the moving coil head mechanism might need a magnetic jump-start, he probed the hard drive case with a magnetic parts holder until the head started moving again. He was then able to recover the data and retire the drive. Seems like a great tip to file away for a bad day.
It seems like we’re getting closer to a
Star Trek
future every day. No, we probably won’t get warp drives or transporters anytime soon, and if we’re lucky velour tunics and Spandex unitards won’t be making a fashion statement either. But we may get something like Dr. McCoy’s medical scanner thanks to work out of MIT using
lasers to conduct a non-contact medical ultrasound study
. Ultrasound exams usually require a transducer to send sound waves into the body and pick up the echoes from different structures, with the sound coupled to the body through an impedance-matching gel. The non-contact method uses pulsed IR lasers to penetrate the skin and interact with blood vessels. The pulses rapidly heat and expand the blood vessels, effectively turning them into ultrasonic transducers. The sound waves bounce off of other structures and head back to the surface, where they cause vibrations that can be detected by a second laser that’s essentially a sophisticated motion sensor. There’s still plenty of work to do to refine the technique, but it’s an exciting development in medical imaging.
And finally, it may actually be that the future is less
Star Trek
more
WALL-E
in the unlikely event that
Segway’s new S-Pod personal vehicle
becomes popular. The two-wheel self-balancing personal mobility device is somewhat like a sitting Segway, except that instead of leaning to steer it, the operator uses a joystick. Said to be inspired by the decidedly not
Tyrannosaurus rex
-proof “Gyrosphere” from
Jurassic World
, the vehicle tops out at 24 miles per hour (39 km/h). We’re not sure what potential market for these things would need performance like that – it seems a bit fast for the getting around the supermarket and a bit slow for keeping up with city traffic. So it’s a little puzzling, although it’s clearly easier to fully automate than a stand-up Segway. | 30 | 9 | [
{
"comment_id": "6207817",
"author": "RoGeorge",
"timestamp": "2020-01-06T00:35:21",
"content": "“It looks like the third decade of the 21st century is off…”OMG, how much did I sleep?!:o)",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6207822",
"auth... | 1,760,373,634.306949 | ||
https://hackaday.com/2020/01/05/converting-a-drill-press-into-a-milling-machine/ | Converting A Drill Press Into A Milling Machine | Sharon Lin | [
"Tool Hacks"
] | [
"cheap mill",
"drill press",
"ham radio mods"
] | Mills are a huge investment, and for hobbyists without the space to install their own personal mill, it can sometimes be a pain to have to find a facility with a mill to complete your project.
What if you could
convert your drill press
into a mill instead? YouTuber [
Small Metalworking Machines
] explores this in his video, where he takes a small Central Machinery drill press and adds a few mods. He took some steps to improve the quill, spindle, and bearings — boring down the quill, replacing the bearings, and finally turning and re-threading the spindle it at 1/2-20.
With the adjustments, he was able to add in a cheap drill chuck, which fit in quite nicely with just a slight wobble of 5 thousandths on either side. To introduce some control, he added in a worm gear to engage a gear on the spindle. A pivot point disengages the worm gear, while bearings provide it controlled movement from the worm wheel.
He also added a cheap milling table from eBay, attached to the base of the drill press, all for a total of $120. While it’s not perfect, it’s still significantly less expensive than buying a mill!
[Thanks to jafinch78 for the tip!] | 30 | 13 | [
{
"comment_id": "6207775",
"author": "egoi",
"timestamp": "2020-01-05T21:29:27",
"content": "Keep in mind that those motors in those drill presses are designed to work in S2 duty cycle. Use it as a mill and you’ll likely burn it out quickly.",
"parent_id": null,
"depth": 1,
"replies": [
... | 1,760,373,634.369321 | ||
https://hackaday.com/2020/01/05/3d-pens-can-make-ugly-drone-parts-that-almost-work/ | 3D Pens Can Make Ugly Drone Parts That Almost Work | Donald Papp | [
"3d Printer hacks",
"drone hacks"
] | [
"3D pen",
"3D printing pen",
"drone",
"micro quad",
"quadcopter"
] | Small hobby aircraft and light plastic parts go hand in hand, and a 3D printing pen makes lightweight plastic
things
without the overhead of CAD work and running a 3D printer. So could a 3D pen create useful plastic bits for small quadcopters? [Michael Niggel] decided to find out by
building his drone parts with a 3D pen loaded with ABS plastic
. He mostly discovered that the created objects could politely be said to look like they were sketched by a toddler, but that’s not all he learned.
He found that in general creating an object was harder than the marketing materials implied. As soon as the filament exits the pen’s nozzle, the thin little molten line of plastic cools rapidly and does two things: it has a tendency to curl, and loses its desire to stick to things. [Michael] found the whole affair worked much less like ‘drawing in thin air’ and rather more like piping frosting, or caulking.
An almost functional micro quad frame. The arms aren’t rigid enough to hold the motors vertical when under power.
Nevertheless, [Michael] sought to discover whether a 3D pen could be used to make quick and dirty parts of any use. He created two antenna brackets and one micro quad frame. All three are chaotic messes, but one antenna bracket was perfectly serviceable. The 3D pen was indeed able to create a strangely-shaped part that would have been a nightmare to CAD up. The other antenna part worked, but didn’t do anything a zip tie wouldn’t have done better. The rapid cooling of the plastic from the 3D pen has an advantage: extrusions don’t “droop” like a glob of hot glue does before it hardens.
By now, [Michael] agreed that the best way to create a plastic part of any complexity whatsoever seemed to be to draw sections flat, build them up in layers, then use the pen to weld the pieces together and add bulk. The micro quad frame he made in this way doesn’t look any nicer than the other attempts, but it did hold the parts correctly. Sadly, it would not fly. Once the motors powered up, the arms would twist and the flight controller was unable to compensate for motors that wouldn’t stay straight. This could probably be overcome, but while the end result was dirty it certainly wasn’t quick. The 3D pen’s niche seems restricted to simple, unstressed parts that aren’t permitted to gaze up themselves in a mirror.
If you have a 3D pen, we’d like to remind you of
this mini spool design whose parts are welded together with the pen itself
. For bigger jobs,
a high-temperature hot glue gun can be used to dispense PLA instead
. | 23 | 13 | [
{
"comment_id": "6207744",
"author": "Col. Panek",
"timestamp": "2020-01-05T18:48:02",
"content": "I think I would have started with a couple popsickle sticks.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6207752",
"author": "fpgacomputer",
... | 1,760,373,634.448618 | ||
https://hackaday.com/2020/01/05/space-saving-servo-tester-console-looks-space-worthy/ | Space-Saving Servo Tester Console Looks Space-Worthy | Kristina Panos | [
"Arduino Hacks"
] | [
"3d printed hinge",
"Arduino Uno",
"folding enclosure",
"servo",
"servo tester"
] | You know how it goes — sometimes you just have to stop in the middle of a project and build yourself a tool that vastly improves your workflow as soon as it’s completed. [Ikkalebob] aka [Will Cogley] on YouTube is working on some super secret project that requires a whole bunch of servos. And since all of them have to be tested and set,
he built this adorable servo tester
as a time-saving gift to himself.
This tester revolves around an Adafruit 16-channel servo driver and an Arduino Uno. The servos show up on the screen in groups of four, and can be tested four at a time with the pots. The buttons let [Ikkalebob] move up and down between the groups. The SainSmart LCD proved to be more difficult to set up than others, but [Ikkalebob] did you a solid and tweaked the library. It’s available along with his code and STLs.
Speaking of STLs, we really dig the mini NASA console look and the folding enclosure. Leveraging the print process to build hinges and other things is awesome, and so is getting away with using fewer fasteners. You can see a bit of how [Ikkalebob] designed it in the video after the break.
Depending on what you’re doing with servos, you might want a different kind of testing suite.
Here’s one that’s geared toward RC pilots
. | 7 | 5 | [
{
"comment_id": "6207710",
"author": "Reply",
"timestamp": "2020-01-05T15:58:40",
"content": "Laying out the enclosure flat and folding it afterwards is a really clever idea!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6207720",
"author": "bl",
"tim... | 1,760,373,634.496794 | ||
https://hackaday.com/2020/01/05/all-youve-ever-wanted-to-know-about-compilers/ | All You’ve Ever Wanted To Know About Compilers | Bryan Cockfield | [
"Software Hacks"
] | [
"arm",
"c++",
"code",
"compiler",
"howto",
"instructional",
"open source",
"programming",
"self compiling",
"tutorial",
"x86"
] | They say that in order to understand recursion, you must first understand recursion. Once you master that concept, you might decide that it’s time to write your own compiler that can compile itself as a fun side project. According to [Warren] aka [DoctorWkt],
who documented every step of writing this C compiler from scratch
, a true compiler will be able to do that.
Some of the goals for the project included self-compiling, focusing on a real hardware platform, practicality, and simplicity. [Warren] outlines a lot of the theory of compilers as well, including all the lexical, grammar, and semantic analysis and then the final translation into assembly language, but really focuses on making this compiler one for practical use rather than just a theoretical implementation. He focuses on Intel x86-64 and 32-bit ARM platforms too, which are widely available.
This project is a long read and very thoroughly documented at around 100,000 words, so if you’ve ever been interested in compilers this is a great place to start. There are a lot of other great compiler tools floating around too,
like the Compiler Explorer
which shows you generated code as you write in a higher level language.
[via
Hackaday.io
] | 21 | 8 | [
{
"comment_id": "6207695",
"author": "Jim Shortz",
"timestamp": "2020-01-05T13:29:15",
"content": "The Dragon book (Aho and Sethi) is the standard on this topic. However, Wirth’s Compiler Construction is very good as well and is a free download.",
"parent_id": null,
"depth": 1,
"replie... | 1,760,373,634.557729 | ||
https://hackaday.com/2020/01/05/arduino-wristwatch-has-led-hands/ | Arduino Wristwatch Has LED Hands | Al Williams | [
"Arduino Hacks",
"clock hacks"
] | [
"arduino",
"DS3231",
"watch"
] | When you read “Arduino wristwatch”, you fall into the trap of envisioning an Arduino UNO clumsily strapped to someone’s wrist. [Marijo Blažević’s]
creation is much more polished than that
. A round circuit board holds two surface mount ICs and 12 LEDs. The whole thing looks nice fit snugly inside of a watch body. It isn’t a Rolex, but it does have considerable geek cred without being unwearable in polite company.
One IC is an AVR micro, of course. The other is a DS3231 real time clock with built-in crystal. A CR2032 keeps it all running. The main body, the outer ring, the bottom, and the buttons are 3D printed in PLA. The crystal and the band are the only mechanical parts not printed. The
bill of materials
shows a 36mm crystal and even provides links for all the parts.
You don’t want to run LEDs all the time because it is bad on the battery. When you press the button once, you get one of the LEDs to light to show the hours. Another press reads the minutes in units of 5 minutes. A third press shows you one of five LEDs to show how many minutes to add. For example, if the time is 9:26 you’d get LED 9 (hours), LED 5 for 25 minutes, and the third press would show LED 1 for 1 extra minute. If either of the minute indicators show 12 o’clock, that indicates zero minutes.
The exciting thing, of course, is that you can program it beyond the
code
on GitHub. Already it can tell time and display the temperature. You don’t have a lot of I/O, but you ought to be able to get some more options and maybe some flashy LED blinking patterns in if you try. | 20 | 5 | [
{
"comment_id": "6207685",
"author": "mxb",
"timestamp": "2020-01-05T11:07:47",
"content": ":) if it was once an AVR micro, what did it become?",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6207687",
"author": "Reply",
"timestamp": "2020-01-... | 1,760,373,634.633493 | ||
https://hackaday.com/2020/01/04/making-a-custom-caliper-case-for-pros/ | Making A Custom Caliper Case For Pros | Sharon Lin | [
"Tool Hacks"
] | [
"cad",
"caliper",
"cnc routing",
"laser engraving",
"woodworking"
] | Every professional has a tool set that they would never part with. Likewise, for experimental physicists, mechanical engineers, and tinkerers, a caliper set can be unspeakably crucial to their work. That’s why [Andrew Birkel] designed his own
personal caliper set
to fit just the right proportions for his tools while adding a bit of personal flair.
The project uses CNC routing, Solidworks for CAD, laser engraving, and woodworking to design the custom case for a set of calipers, metric and English screw pitch gauges, fillet gauges, and radius gauges. It’s a practical build for a custom tool set that doesn’t already come with a case of its own. The particular tools were chosen for their use in particle physics experiments: for determining threads, inside and outside curvatures, and measuring length, depth, and width.
The box was made from an oversized piece of wood with holes drilled into the sides. After compiling the G-code program for the build, the two halves of the box was was milled from the wood. The first run on the CNC mill with aluminum managed to cause the grain to split, so [Birkel] went with a CNC router instead. Once the piece was sanded, hidden barrel hinges were added. The finished box was wiped down with mineral oil and teak oil to bring out the natural coloration of the wood as well as to add protection (lacquer mixed into the oil). To finish it off, the case was customized with a laser engraved name and email for identification.
It’s a pretty slick build to say the least, and certainly one that can be customized to the dimensions of whatever tools your personal caliper set happens to have. | 19 | 7 | [
{
"comment_id": "6207481",
"author": "cdmurray88",
"timestamp": "2020-01-04T13:42:15",
"content": "That’s beautiful and I would pay to have custom cases like that made for things like my calipers, sliding squares, chisels, etc. Especially if they all had the same outer dimensions so the could fit ni... | 1,760,373,634.697918 | ||
https://hackaday.com/2020/01/03/dinural-reef-control-realistically-insolates-your-aquarium/ | Diurnal Reef Control Realistically Insolates Your Aquarium | Gerrit Coetzee | [
"LED Hacks"
] | [
"arduino",
"coral",
"led",
"light",
"reef",
"simulate",
"tide"
] | [Phillip]’s project is not just great for learning new words, it also
shows just how complex natural systems can be.
As we know from news around the word, reefs are delicate systems prone to damage from just about any imaginable threat. Escaped aquarium fish, sunscreen, and the wayward feet of well meaning tourists to name a few. So it’s no wonder that aquarium hobbyists sometimes go to incredible lengths to
simulate
the natural environments these creatures live in.
While [Phillip] is still tinkering with his designs for this project, we found the data he included really interesting. His goal is to be able to plug in any coordinate on the earth and have the lights replicate the location. That includes not just the sun, but also the light from the moon as many corals seem to only spawn during certain tides. Of course no LED is perfect so he’s even experimenting with putting light sensors under the water to provide a feedback loop to make it perfect.
We really like the ambition of this project and we hope he continues. | 14 | 5 | [
{
"comment_id": "6207430",
"author": "snow",
"timestamp": "2020-01-04T06:52:32",
"content": "should that no say diurnal instead of dinural?",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6207472",
"author": "e",
"timestamp": "2020-01-04T12:58... | 1,760,373,634.754411 | ||
https://hackaday.com/2020/01/03/tracking-vaccination-history-with-invisible-tattoos/ | Tracking Vaccination History With Invisible Tattoos | Sharon Lin | [
"Science"
] | [
"biohacking",
"health hacking",
"research",
"tattoo",
"vaccine"
] | Nowadays, we still rely on medical records to tell when our last vaccinations were. For social workers in developing countries, it’s an incredibly difficult task especially if there isn’t a good standard in place for tracking vaccinations already.
A team at the Massachusetts Institute of Technology may be providing a solution – they’ve developed a safe ink to be
embedded into the skin
alongside the vaccine, only visible under a special light provided by a smartphone camera app. It’s an inconspicuous way to document the patient’s vaccination history directly into their skin and low-risk enough to massively simplify the process of maintaining medical records for vaccines.
The tatoo is made up of tiny quantum dots – semiconductor crystals that reflect light – that glow under infrared light. The pattern is delivered using dissolving microneedles made up of polymers and sugar. While the solution remains in the proof-of-concept stage, the researchers were successfully able to detect patterns embedded into the skins of rats nine months after the initial injection. On human cadavers, the patterns remained identifiable after five years of simulated sun exposure.
This could certainly mean new possibilities for decentralized information delivery and storage. Alongside
biodegradable implants
and
power pills
, we could be looking at an exciting frontier for biohacking. | 57 | 17 | [
{
"comment_id": "6207398",
"author": "Alexander Wikström",
"timestamp": "2020-01-04T03:38:21",
"content": "“they’ve developed a safe ink to be embedded into the skin alongside the vaccine, only visible under a special light provided by a smartphone camera app.” First off, is other ink used for regul... | 1,760,373,634.909651 | ||
https://hackaday.com/2020/01/03/voltmeter-clock-looks-great-on-display/ | Voltmeter Clock Looks Great On Display | Lewin Day | [
"clock hacks"
] | [
"clock",
"multimeter clock",
"voltmeter"
] | Voltmeters are cheap, and have a great industrial aesthetic about them. This makes them prime candidates for hackers looking to do a clock build. [Brett Oliver] went down this very road,
and built a very stylish timepiece along the way.
[Brett] initially wanted to go with 240-degree voltmeters, however the cost was prohibitive, so settled for the more common 90-degree models. New dials were produced by first sanding down the old dials, repainting in an old-fashioned off-white, and then applying the new graphics with inkjet transfer paper.
The attention to detail continues with the case. [Brett] aimed to build the clock with an old-school lab equipment aesthetic. A large piece of mahogany was crafted into the base. A clear plastic cover was sourced from eBay, which really makes the piece. Large buttons and toggle switches were chosen to complete the look.
On the electronic side of things, it’s all run by a PIC16F628A, which controls the voltmeters via PWM. Running with a 20MHz crystal, the PIC is not a great timekeeper.
Instead, the whole show is synchronized to [Brett]’s master clock we featured a few years back.
Building a clock is a rite of passage for a hacker, and [Brett]’s example goes to show how craftsmanship can really pay off in this pursuit. Video after the break. | 8 | 5 | [
{
"comment_id": "6207365",
"author": "Tim Walther",
"timestamp": "2020-01-04T00:15:13",
"content": "Nice build! I have the suspicion the power supply could do with better regulation: you can see both the minutes and hours meters jump a bit ahead whenever the second meter drops back to zero. The only... | 1,760,373,634.802382 | ||
https://hackaday.com/2020/01/03/unique-3d-printer-turned-cnc-engraver/ | Unique 3D Printer Turned CNC Engraver | Tom Nardi | [
"3d Printer hacks",
"Tool Hacks"
] | [
"3D printer mod",
"cnc",
"engraver",
"spindle"
] | As we’ve said in the past, one of the most exciting things about the proliferation of low-cost desktop 3D printers (beyond all the little boats we get to see on Reddit), is the fact that their motion control systems are ripe for repurposing. Outfitting a cheap 3D printer with a drag knife, pen holder, or even a solid-state laser module, are all very common ways of squeezing even more functionality out of these machines.
But thanks to the somewhat unusual nature of his printer,
[Hammad Nasir] was able to take this concept a bit farther
. Being considerably more rigid than the $99 acrylic-framed box of bolts we’ve become accustomed to, he was able to fit it with a basic spindle and use it for CNC engraving. He won’t be milling any steel on this rig, but judging by the pictures on the Hackaday.io page for the project, it does a respectable job cutting designs into plastic at least.
The IdeaWerk 3D printer that [Hammad] used for this project is phenomenally overbuilt. We don’t know whether the designers simply wanted to make it look futuristic and high-tech (admittedly, it does look like it could double as a movie prop) or they thought there was a chance it might get thrown down the stairs occasionally. In either event, it’s built like an absolute tank.
While the frame on lesser printers would likely flex as soon as the bit started moving across the workpiece, this thing isn’t going anywhere. Of course this machine is presumably still running on the standard GT2 belt and NEMA 17 arrangement that has been used in desktop 3D printers since the first wooden machines clattered to life. So while the frame might be ready to take some punishment, the drive system could respectfully disagree once the pressure is on.
Modification was simplified by the fact that the hotend and extruder assembly on the IdeaWerk is mounted to the X axis with just a single bolt. This makes it exceptionally easy to design alternate tool mounts, though arguably the 3D printed motor holder [Hammad] is using here is the weak link in the entire system; if it’s going to flex anywhere, it’s going to be there.
If you’re more photonically inclined, you might be interested in this similarly straightforward project that sees
a 2.5 W laser module get bolted onto an entry level 3D printer
. | 4 | 3 | [
{
"comment_id": "6207376",
"author": "Ostracus",
"timestamp": "2020-01-04T01:39:20",
"content": "Now we can start up the HaD comments on “You got your peanut butter on my chocolate!” , “You got your chocolate in my peanut butter!”, “Two great tastes that taste great together.”",
"parent_id": nu... | 1,760,373,634.967541 | ||
https://hackaday.com/2020/01/03/you-could-be-a-manufacturing-engineer-if-you-could-only-find-the-time/ | You Could Be A Manufacturing Engineer If You Could Only Find The Time | Mike Szczys | [
"cons",
"Lifehacks"
] | [
"2019 Hackaday Superconference",
"manufacturing",
"Mentoring",
"noisebridge",
"professional development",
"Supercon"
] | Let’s be honest, Ruth Grace Wong can’t teach you how to be a manufacturing engineer in the span of a twenty minute talk. But no-one can. This is about
picking up the skills for a new career without following the traditional education path
, and that takes some serious time. But Grace pulled it off, and her talk at the 2019 Hackaday Superconference shares what she learned about reinventing your career path without completely disrupting your life to do so.
Ruth got on this crazy ride when she realized that being a maker made her happy and she wanted to do a lot more of it. See wanted to be “making stuff at scale” which is the definition of manufacturing. She took the hacker approach, by leveraging her personal projects to pull back the veil of the manufacturing world. She did a few crowd funding campaigns that exposed her to the difficulties of producing more than one of something. And along the way used revenue from those projects to get training and to seek mentorships.
Those mentorships can come in many forms. Much of her success stems from the personal connections she made at conferences, through online interactions, and at
Noisebridge, her local hackerspace in San Francisco
. One of the most interesting stories she mentions is a mentorship hack where she found people with the skills she wanted to learn, and convinced them to give a class about it if she did all the organizational legwork.
She had begun to learn Mandarin when the opportunity to start working on a manufacturing project with a startup came along. But her skills acquisition phase never ended. Ruth advocates for personal curiosity, and used her own as radar to pick up on new things to learn that others may have missed.
But what we all might benefit from most in this talk is her discussion at the end about finding time. Ruth says “your productivity will never increase”, because productive people are already using their available time. That doesn’t mean you can’t pick up new career skills on the side. But it does mean you need to throw some things overboard. From showing up late, to adopting a clean clothes box, Ruth certainly dipped into the well of life hacks to get there. She succeeded, and two years after the original epiphany she’s finally landed a job as a manufacturing engineer. | 9 | 5 | [
{
"comment_id": "6207341",
"author": "Joe Bonasses",
"timestamp": "2020-01-03T21:08:04",
"content": "Why would you want to, professionally? Shit pay, sixty hour work weeks…..no thanks",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6207344",
"author"... | 1,760,373,635.011753 | ||
https://hackaday.com/2020/01/03/the-quadratic-equation-solution-a-few-thousand-years-in-the-making/ | The Quadratic Equation Solution A Few Thousand Years In The Making | Al Williams | [
"Featured",
"Misc Hacks"
] | [
"math",
"polynomial",
"quadratic"
] | Everyone learns (and some readers maybe still remember) the quadratic formula. It’s a pillar of algebra and allows you to solve equations like Ax
2
+Bx+C=0. But just because you’ve used it doesn’t mean you know how to come up with the formula itself. It’s a bear to derive so the vast majority of us simply memorize the formula. A Carnegie Mellon mathematician named Po-Shen Loh didn’t expect to find a new way to derive the solution when he was reviewing math materials for middle school use to make them easier to understand. After all, people have been solving that equation for about 4,000 years. But that’s
exactly what he did
.
Before we look at the new solution, let’s talk about why you want to solve quadratic equations. They are used in many contexts. In ancient times you might use them to determine how much more crop to grow to cover pay tax payments without eating in to the crop you needed to subsist. In physics, it can describe motion. There’s seemingly
no end to how many things you can describe with a quadratic equation
.
Babylonians, in particular, would solve simultaneous equations to find the roots of a quadratic. Egyptians, Grecians, Indians, and Chinese peoples used graphical methods to solve the equations. The entire history is a bit much to get into, but still
a great read
. For this article, let’s dig into how the new derivation was discovered.
Setting Up the Equation
So what’s the method? You watch Loh explain it himself in the video, below. Suppose you have a standard quadratic equation for whatever reason that looks like this:
x
2
-6x+3=0
In this case, A=1, B=-6, and C=3. Note that for Loh’s method to work, A should equal 1, but if it doesn’t you can always divide both sides by A to make that true. For example, consider this equation:
3x
2
-18x+9=0
It will have the same roots as the first one because if you divide both sides by 3, you get the first equation.
The Polynomial Factor
To factor a polynomial into two binomials we can use FOIL (First/Outer/Inner/Last). So we know that:
x
2
-6x+3=(x-S)(x-R)
Where we just made up S and R. They exist, but we don’t know what they are yet. However, for the answer to be zero, you can see that the equation will be zero when x=S or X=R so that means S and R are the roots of the equation.
So What’s S and R?
It sounds silly, but let’s multiply out the binomials into another polynomial. Remember FOIL:
x
2
-6x+3=x
2
-(S+R)x+SR
If you look at that for a second, you will probably realize that S times R must be 3. We also know they add up to 6. At this point, you can probably just guess the roots, but let’s make it formal.
The roots of a polynomial like this will be in the form of
U±z
. So if
S=U+z
and
R=U-z
, the only way to make
(U+z)+(U-z)
equal to 6 is if U is 6/2. Since B is -6 in this example, we can intuit that U must be -B/2 in the general case.
Home Stretch
So we now know the roots are
-B/2+z
and
-B/2-z
. We know that B is -6. We also know the answer is when we multiply those roots together must be C (3, for our example). So we can write:
(-(-6)/2+z)(-(-6)/2-z)=3
Or:
(3+z)(3-z)=3
Do the FOIL method again and get:
9+3z-3z-z
2
=3
The middle terms will always cancel out so you get:
9-z
2
=3
Subtract 3 from both sides and add z squared to both sides:
6=z
2
Since the root must be
-B/2±z
we know that our two roots are
3+√6
and
3-√6
.
The Key and the Catch
The point is, none of this was hard to remember or work out. Just remember that you rewrite the zero as
(x-S)(x-R)
and the rest follows very logically.
The only real problem is not many quadratic equations have A=1. For example, suppose you throw a ball straight up from 5 meters above the ground with a velocity of 15 m/s. We want to know when the ball will hit the ground.
Gravity is going to pull down on the ball at about 4.9 meters per second squared (assuming gravity accelerates at -9.8 m/s
2
). The physics formula is
(at
2
)/2
so we get our first term of -4.8t
2
. The second term will represent the speed of the ball which is simply 15t. We also started 5 meters above the ground, so we will add 5 and wind up with:
-4.8t
2
+15t+5
This formula will tell you where the ball is assuming you throw at t=0. We want to know when it hits the ground so that will be one of the roots:
-4.8t
2
+15t+5=0
To use the new method, just divide it all through by -4.8 to get:
t
2
-3.125t-1.04=0
So now B=-3.125 and C=-1.04. We know the root will be
-B/2±z
or 1.5625 and that z
2
will equal
(1.5625)
2
+1.04
.
That’s 3.48 (about) and the square root is about 1.866. The roots, then, are 1.5625±1.866. Working that out, we get -0.30 and 3.4285. The negative root is nonsense in this case but the ball will land almost 3.5 seconds after you throw it.
If you don’t trust our work, ask
Wolfram Alpha
or plug 3.4285 back into the original formula. Wolfram says 3.43 and the check your own work says 0.005 meters at that time, so given that I rounded a few times, that’s pretty close. Besides, I’m ignoring things like air resistance. This
specific calculator
says 3.36 seconds, which is still pretty close.
In Summary
If you prefer things in algorithmic steps, here you go:
Find A, B, and C for the quadratic equation.
If necessary, divide by A so that A now is 1.
Write
-(B/2)
2
-z
2
=C
Solve for z (since you know B and C)
Roots are
-B/2±z
Everything Old is New Again
We get it. Many people may have figured this out before. But if they did, they apparently forgot to share it with anyone in any permanent form. If you read the actual paper, you’ll see how easy it is to symbolically derive the “old” standard formula. Compare that to the
traditional method
. If you read the proof, it seems simple enough, but go back in a few weeks and try to work it out yourself. Not so easy. This is also much easier to remember even if you don’t want to derive it every time.
Of course, making A=1 is part of the trick. It is well known, for example, that the product of the roots of a quadratic is
C/A
. Since we know A=1, it follows that the product of S and R are also C, using this method. Normalizing A to 1 is also an old trick and is sometimes called a reduced quadratic equation. However, it doesn’t look like anyone put all the pieces together until now.
If you don’t like Wolfram Alpha, there’s always
Mathics
(hint: use
Solve[-4.8t^2+15t+5==0,t]
). There are also
specific calculators
. Or just bite the bullet and keep everything in a
Jupyter Notebook
. | 38 | 20 | [
{
"comment_id": "6207302",
"author": "RW ver 0.0.1",
"timestamp": "2020-01-03T18:16:31",
"content": "I feel like I turned this in on a math test once and got it back with a big red ink 0 and WHY??? and WHERE DID THIS COME FROM ??? and USE THE FORMULA !!! at the end, with an ensuing discussion of “Bu... | 1,760,373,635.265343 | ||
https://hackaday.com/2020/01/03/hackaday-podcast-048-truly-trustworthy-hardware-glowing-uranium-marbles-bitstreaming-the-usb-chaos-of-congress/ | Hackaday Podcast 048: Truly Trustworthy Hardware, Glowing Uranium Marbles, Bitstreaming The USB, Chaos Of Congress | Mike Szczys | [
"Hackaday Columns",
"Podcasts"
] | [
"Bunnie Huang",
"camera sensor",
"Circuit Sculpture",
"Hackaday Podcast",
"random numbers",
"secure hardware",
"uranium"
] | Hackaday editors Elliot Williams and Mike Szczys kick off the first podcast of the new year. Elliot just got home from Chaos Communications Congress (36c3) with a ton of great stories, and he showed off his electric cargo carrier build while he was there. We recount some of the most interesting hacks of the past few weeks, such as 3D-printed molds for making your own paper-pulp objects, a rudimentary digital camera sensor built by hand, a tattoo-removal laser turned welder, and desktop-artillery that’s delivered in greeting-card format.
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 048 Show Notes:
New This Week:
Hackaday’s 36C3 Articles
Honoring Chuck Peddle; Father Of The 6502 And The Chips That Went With It
Chuck Peddle on the Amp Hour Podcast
Interesting Hacks of the Week:
3D Printing Paper — Sort Of
194 LED Ball Is Free-Form Soldering On Another Level
Arduino Wire Bender Probably Won’t Kill All Humans
LED Polyhedron seen at 36C3
VGA Signal In A Browser Window, Thanks To Reverse Engineering
Spoofing Cell Networks With A USB To VGA Adapter
Osmo-fl2k – osmo-fl2k – Open Source Mobile Communications
36C3: Open Source Is Insufficient To Solve Trust Problems In Hardware
Can We Build Trustable Hardware? « bunnie’s blog
Roll The Bones Chernobyl Style
Image Sensor From Discrete Parts Delivers Glorious 1-Kilopixel Images
Alex’s
Tiny LED Matrices
Quick Hacks:
Elliot’s Picks:
Laser Welding With A Tattoo Removal Gun
Turning Sounds From A Flute Into Sheet Music
Drill Thrice, Solder Once
Mike’s Picks:
Bend It Like Bhoite: Circuit Sculptures Shatter The Bounds Of Flatland
Catapult Your Best Wishes with this 3D Printable Card
3D Printed Pulsejet Uses Tesla Valve
Can’t-Miss Articles:
Ask Hackaday: How Do You Keep The 3D Printer From Becoming EWaste
2019: As The Hardware World Turns
Greg Davil’s FPGA Designs (
OrangeCrab
and
ArcticKoala
)
Mozilla’s
Deep Speech implementation | 7 | 2 | [
{
"comment_id": "6207337",
"author": "jup",
"timestamp": "2020-01-03T20:39:05",
"content": "Have you fully undetstood the sense of the german sentence below the hackaday logo in the picture above? I guess not ;)",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": ... | 1,760,373,635.180365 | ||
https://hackaday.com/2020/01/03/the-fun-is-on-the-christmas-tree-with-this-playable-duck-hunt-decoration/ | The Fun Is On The Christmas Tree With This Playable Duck Hunt Decoration | Dan Maloney | [
"Holiday Hacks"
] | [
"christmas",
"duck hunt",
"game",
"ir",
"led",
"light gun",
"nes",
"Ninetendo",
"sensor"
] | ‘Tis the season for leftovers, be they food, regifted presents, or the decorations left behind in the wake of the festivities. Not to mention the late tips we get for holiday-themed builds, like
this Duck Hunt ornament that’s completely playable
.
Details are sparse in [wermy]’s video below, but there’s enough there to get the gist. The game is based on the Nintendo classic, where animated ducks fly across the screen and act as targets for a light pistol. Translating that to something suitable for decorating a Christmas tree meant adding an Arduino and an IR LED to the original NES light pistol, and building a base station with a Feather and a small LCD screen into a case that looks like [The Simpsons] TV. An LED on each 3d-printed duck target lights in turn, prompting you to blast it with the gun. An IR sensor on each duck registers hits, while the familiar sound effects are generated by the base, which also displays the score. Given a background of festive blinkenlights, it’s harder than it sounds – see it in action briefly below.
[wermy] has done some interesting builds before, like
a RetroPie in an Altoids tin
and
a spooky string of eyes for Halloween
. We hope he’ll come through with a more detailed build video for this project at some point – we’re particularly interested in those beautiful multi-color 3D-prints.
[via
sudomod
] | 5 | 3 | [
{
"comment_id": "6207289",
"author": "Rafał Sawczuk",
"timestamp": "2020-01-03T17:35:56",
"content": "Last year just for the laughs I 3D printed a goatse christmas tree ornament. It didn’t go well with my family once they discovered it during christmas night. They forced me to go to psychiatrist.",
... | 1,760,373,635.123629 | ||
https://hackaday.com/2020/01/03/this-week-in-security-totok-edgium-chrome-checks-your-passwords-and-more/ | This Week In Security: ToTok, Edgium, Chrome Checks Your Passwords, And More | Jonathan Bennett | [
"Hackaday Columns",
"Security Hacks"
] | [
"Edgium",
"sms",
"This Week in Security",
"ToTok"
] | Merry Christmas and happy New Year! After a week off, we have quite a few stories to cover, starting with
an unexpected Christmas gift from Apple
. Apple has run an invitation-only bug bounty program for years, but it only covered iOS, and the maximum payout topped out at $200K. The new program is open to the public, covers the entire Apple product lineup, and has a maximum payout of $1.5 million. Go forth and find vulnerabilities, and make sure to let us know what you find.
ToTok
The United Arab Emirates had an odd policy regarding VoIP communications. At least on mobile networks, it seems that all VoIP calls are blocked — unless you’re using a particular app: ToTok. Does that sound odd? Is your “Security Spider Sense” tingling? It probably should. The
New York Times covered ToTok
, claiming it was actually a tool for spying on citizens.
While that coverage is interesting, more meat can be found in [Patrick Wardle]’s
research on the app
. What’s most notable, however, is the distinct lack of evidence found in the app itself. Sure, ToTok can read your files, uploads your contact book to a centralized server, and tries to send the device’s GPS coordinates. This really isn’t too far removed from what other apps already do, all in the name of convenience.
It seems that ToTok lacks end-to-end encryption, which means that calls could be easily decrypted by whoever is behind the app. The lack of malicious code in the app itself makes it difficult to emphatically call it a spy tool, but it’s hard to imagine a better way to capture VoIP calls. Since those articles ran, ToTok has been removed from both the Apple and Google’s app stores.
SMS Keys to the Kingdom
Have you noticed how many services treat your mobile number as a positive form of authentication? Need a password reset? Just type in the six-digit code sent in a text. Prove it’s you? We sent you a text. [Joakim Bech] discovered a weakness that takes this a step further: all he needs is access to a single SMS message, and
he can control your burglar alarm
from anywhere. Well, at least if you have a security system from Alert Alarm in Sweden.
The control messages are sent over SMS, making them fairly accessible to an attacker. AES encryption is used for encryption, but a series of errors seriously reduces the effectiveness of that encryption. The first being the key. To build the 128-bit encryption key, the app takes the user’s four-digit PIN, and pads it with zeros, so it’s essentially a 13 bit encryption key. Even worse, there is no message authentication built in to the system at all. An attacker with a single captured SMS message can brute force the user’s PIN, modify the message, and easily send spoofed commands that are treated as valid.
Microsoft Chrome
You may have seen the news, Microsoft is giving up on their Edge browser code, and will soon begin shipping a Chromium based Edge. While that has been a source of entertainment all on its own, some have already begun taking advantage of the new bug bounty program for Chromium Edge (Edgium?). It’s an odd bounty program, in that Microsoft has no interest in paying for bugs found in Google’s code. As a result, only bugs in the Edge-exclusive features qualify for payout from Microsoft.
As [Abdulrahman Al-Qabandi] puts it, that’s a very small attack surface. Even so,
he managed to find a vulnerability that qualified
, and it’s unique. One of the additions Microsoft has made to Edgium is a custom new tab page. Similar to other browsers, that new tab page shows the user their most visited websites. The problem is that the site’s title is shown on that page, but without any sanity checking. If your site’s title field happens to include Javascript, that too is injected into the new tab page.
The full exploit has a few extra steps, but the essence is that once a website makes it to the new tab page, it can take over that page, and maybe even escape the browser sandbox.
Chrome Password Checkup
This story is a bit older, but really grabbed my attention. Google has rolled a feature out in Chrome that automatically compares your saved passwords to past data breaches. How does that work without being a security nightmare? It’s clever. A three-byte hash of each username is sent to Google, and compared to the hashes of the compromised accounts. A encrypted database of potential matches is sent to your machine. Your saved passwords, already encrypted with your key, is encrypted a second time with a Google key, and sent back along with the database of possible matches, also encrypted with the same Google key. The clever bit is that once your machine decrypts your database, it now has two sets of credentials, both encrypted with the same Google key. Since this encryption is deterministic, the encrypted data can be compared without decryption. In the end, your passwords aren’t exposed to Google, and Google hasn’t given away their data set either.
The Password Queue
Password changes are a pain, but not usually this much of a pain. A university in Germany suffered a severe malware infection, and
took the precaution of resetting the passwords for every student’s account
. Their solution for bootstrapping those password changes? The students had to come to the office in person with a valid ID to receive their new passwords. The school cited German legal requirements as a primary cause of the odd solution. Still, you can’t beat that for a secure delivery method. | 11 | 7 | [
{
"comment_id": "6207290",
"author": "RW ver 0.0.1",
"timestamp": "2020-01-03T17:44:30",
"content": "Well, good I guess that MS will have their first competitive Browser since Internet Explorer 3, but while I didn’t use Edge as a browser, I found a really convenient feature on it. It will read you a... | 1,760,373,637.09778 | ||
https://hackaday.com/2020/01/03/hololens-brings-video-game-kart-racing-to-life/ | HoloLens Brings Video Game Kart Racing To Life | Tom Nardi | [
"Games"
] | [
"433 mhz",
"augmented reality",
"Hololens",
"kart racing",
"QR codes",
"video game"
] | There aren’t a lot of video game experiences we can easily recreate in the physical realm. You’ll quickly find that jumping on mushrooms in the real world doesn’t have nearly the same appeal as it does in
Super Mario
, and we won’t even get into the dangers of trying to recreate
Frogger
on your local multi-lane. But video game style go-kart racing? We have all the technology to pull that off, somebody just has to put all the pieces together.
Which is precisely what
[Ian Charnas] is trying to do with his latest project
. Using Microsoft’s HoloLens augmented reality headset, electric go-karts, 433 MHz wireless transceivers, and some Arduinos sprinkled in, he’s created the closest thing to
Mario Kart
that us flesh and blood mortals are likely to experience anytime soon.
The HoloLens headset worn by each driver overlays the necessary graphical elements like pickups and weapon effects, as well as puts over-the-top cartoon heads on the other racers. But of course, that’s only half of the story. Seeing the pickups and gadgets doesn’t do you any good if they don’t have any effect on the actual race.
To that end, [Ian] has come up with a way to control the performance of the go-karts using an electronic “backpack” that mounts to each kart. So speed boosting pickups actually make the kart go faster, and if a driver gets hit with a weapon fired at them, they get slowed down.
That’s the high-level version, anyway. There’s obviously a lot going on behind the scenes, some of which are detailed on the Hackaday.io page. One of the interesting notes is that the HoloLens needs visual markers to orient itself, which in the video after the break can be seen as black and white posters dotting the walls alongside the track. As the project progresses, [Ian] is hoping that these can be camouflaged in creative ways (such as being made to look like audience members or checkered flags) to make the overall experience more immersive.
According to [Ian], the next step is to find partners who want to help elevate this from a one-off project to something that you might actually see at an amusement park. We wish him luck, if for no other reason than we
really
want to play the thing ourselves. In the meantime,
we’ll have to settle for racing hacked Power Wheels
. | 12 | 4 | [
{
"comment_id": "6207253",
"author": "Mime",
"timestamp": "2020-01-03T12:27:40",
"content": "That’s pretty cool",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6207263",
"author": "Robert",
"timestamp": "2020-01-03T14:49:44",
"content": "Top Golf an... | 1,760,373,637.284852 | ||
https://hackaday.com/2020/01/03/a-programming-language-that-lets-you-code-with-pixels/ | A Programming Language That Lets You Code With Pixels | Sharon Lin | [
"Art",
"Software Hacks"
] | [
"art",
"programming languages"
] | This programming language gives you programs that resemble modern art. It’s fortunately a feature of the language,
dubbed Piet
after the famed abstract painter Piet Mondrian.
The language uses 20 distinct colors, with the colors cycling from red to yellow to green to cyan to blue to magenta and the lightness cycling from light to normal to dark. The code is formed from graphics made of the recognized colors, with individual pixels holding much of the information. Stacks are used for storing data values, that can exist as integers or as Unicode characters with the proper commands applied.
Numbers in the program are represented by colors, while black blocks indicates edges and white blocks indicate free zones. The interpreter physically slides through blocks in the direction of the Direction Pointer (DP), with hue changes indicating different commands based on the steps of the change.
To execute a program, the Piet language interpreter begins in the upper left codel (or individual code block) of the program, maintaining a DP initially pointed to the right and a Codel Chooser (CC) initially pointed to the left. The DP and CC turn right, left, down, or up depending on the execution.
There is currently a small community of coders developing sample programs, interpreters, IDEs, and compilers for the language. You can check out some of the
sample programs here
. | 23 | 14 | [
{
"comment_id": "6207224",
"author": "Roelh",
"timestamp": "2020-01-03T09:26:31",
"content": "If you like strange languages, check NeuronZoo:https://hackaday.io/project/19287-neuronzoo",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6207437",
"author"... | 1,760,373,637.049689 | ||
https://hackaday.com/2020/01/02/prolific-videos-show-altair-8800-recreation/ | Prolific Videos Show Altair 8800 Recreation | Al Williams | [
"Retrocomputing"
] | [
"8080",
"altair",
"retrocomputing"
] | The January 1975 issue of Popular Electronics introduced the Altair 8800 and hit the newsstands in December of 1974, so it is only natural that around the New Year people start thinking about the old computer. [Shadowtron] did more than think about it. He ordered some replica PCBs and is
building a new one
. Even better, he’s posted an amazing number of videos (up to number 56 as I write this) detailing his progress. You can find part 1, below.
The boards are from
Trailing Edge Technology
. There’s a backplane board (about $100) as well as a few boards to fit it available for about $30 each — unpopulated, of course.
We’ll confess we haven’t watched all 56 videos yet. They cover the construction of the CPU and front panel, the serial I/O board, floppy drives, software, and a homebrew EPROM board (using 1702s, no less).
I have to confess, I’ve always wanted a real Altair — but probably won’t ever get one. But if I were going to build one, this would be the guide to watch as it covers just about everything.
Of course, there are
replicas
(I have a few and even helped develop one). Plus you can run a great simulation on your PC or even in a
browser
. But there’s something about knowing you have the real deal — or as close as you can get to it — that makes an intangible but real difference. | 24 | 10 | [
{
"comment_id": "6207236",
"author": "rtyuty",
"timestamp": "2020-01-03T10:16:38",
"content": "after 2 monts kit will shiped on aliexpress ;)",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6207248",
"author": "ian 42",
"timestamp": "2020-01-03T11:15:49... | 1,760,373,637.229924 | ||
https://hackaday.com/2020/01/02/lc-oscillators-animated/ | LC Oscillators, Animated | Al Williams | [
"Science"
] | [
"animation",
"capacitor",
"dampened sine wave",
"inductor",
"LC",
"LC oscillator"
] | We wish that all the beautiful animations that are available today to understand math and electronics had been around when we were in school. Nonetheless, they are there for today’s students and [Learn Engineering] has
another gorgeous one covering LC oscillation
. Check it out, below.
If you are thoroughly grounded — no pun intended — in LC circuits, you probably won’t learn anything new. However, the animations are worth watching, just to admire them, if nothing else.
We were amused by his statement: “… looks as if the capacitor is saying: ‘you take the energy’ and the inductor then says, ‘no, you take my energy.'” Then we were further amused by [Seraph’s] comment which added, “Resistance in the circuit: ‘Alright, I’ll take the energy, then.'”
Of course, there are other ways to think of an LC circuit. The math isn’t that hard. Most of us learned that the circuit’s mechanical analog is a mass on a spring or a pendulum. The mass’s potential energy stretches out the spring until the spring then pulls it back until the potential energy of the mass pulls it back down.
If you want to experiment virtually, try the
Falstad simulator
. Just remember that if you think the sine wave isn’t dampening to look at the scale. As the sine wave dampens, the simulator will adjust the scale so you keep seeing approximately the same size sine wave.
We never get tired of watching the
Fourier series explained graphically
. Or anything from
[3Blue1Brown]
. | 23 | 8 | [
{
"comment_id": "6207177",
"author": "Old Guy",
"timestamp": "2020-01-03T03:39:16",
"content": "Would it have killed the writer to include one sentence starting with “An LC oscillator is…”?",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6207234",
"au... | 1,760,373,636.833486 | ||
https://hackaday.com/2020/01/02/a-wireless-method-for-pressing-tofu/ | A Wireless Method For Pressing Tofu | Sharon Lin | [
"3d Printer hacks",
"Microcontrollers"
] | [
"hackathon",
"stepper motor",
"tofu"
] | Tofu is a fairly common food in East and Southeast Asian cuisines, but it has also been making its way around vegetarian circles as a meat substitute. While it may be a more environmentally friendly source of protein than meat, it does have the unfortunate side effect of being fairly tedious to cook. To reach the right consistency, tofu requires hours of pressing to drain excess water, which tends to be tedious for most amateur cooks.
A
team of students at HackMIT
developed a contraption that incrementally presses tofu for you, using signals sent over WiFi to initialize the device. Several 3D-printed components extend an existing food container, along with a stepper motor, motor shield, Adafruit Feather HUZZAH, and a screen.
The motor steps at a rate of 30rpm once a signal is sent from a mobile application, causing four connected threaded rods to begin rotating. The tofu tray travels upwards to press against its lid, draining out excess water. A central gear box containers complementary cutouts that allow the tofu platform to travel vertically when shafts are rotated, pushed by nuts below the platform. The students also included a screen indicating time remaining, as well as a notification sent to the user once the tofu is finished being pressed.
It’s certainly a useful solution that will hopefully increase the popularity of tofu-based recipes! | 47 | 23 | [
{
"comment_id": "6207143",
"author": "NoTofu4me",
"timestamp": "2020-01-03T00:28:45",
"content": "Does it fix the taste and consistency? If not, then I still ain’t interested in tofu.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6207296",
"author":... | 1,760,373,637.435959 | ||
https://hackaday.com/2020/01/02/diy-trommel-sifts-compost-in-style/ | DIY Trommel Sifts Compost In Style | Kristina Panos | [
"green hacks",
"Lifehacks"
] | [
"bicycle rims",
"bicycle wheels",
"compost",
"dirt tumbler",
"rotary trommel",
"trommel"
] | Composting is a great idea that helps you and the planet at the same time. But all that stuff is going to break down at different rates, and depending on what you put in there and how soon you want to use the compost, you’ll probably have to sift out some unwanted stuff first.
[Minnear Knives] had a bunch of apricot stones in his compost pile, and it was the pits. He did some research and decided to
build his own rotary trommel to tumble out the trash
. As you will see in the video after the break, it works really well. All he has to do is turn on the motor and shovel raw compost or dirt into one end. Bad stuff tumbles out the other end into a wheelbarrow, while the good stuff is sifted down into a pile under the cylinder. Just look at that rich, fluffy compost.
The best part is that he was able to make it mostly from stuff he had lying around, though he did trade some beer for the v-belt pulley. The cylinder is essentially made from mesh that’s zip-tied to bicycle rims. A 1/4 horsepower motor mounted up top uses that v-belt pulley to spin the cylinder’s rims against casters that are mounted to the frame. Thanks to the pair of bike wheels on the back, he can cart it around the ranch unassisted.
Composting doesn’t have to be any more difficult than a pile in the backyard. But if you don’t have a backyard, why not build
a rotating bin that you can monitor from your phone
? | 22 | 9 | [
{
"comment_id": "6207105",
"author": "ORexy",
"timestamp": "2020-01-02T21:21:52",
"content": "Works really well! But I’m not a huge fan of open rotating equipment at head height for kids with small fingers and long hair, or dusty rocks in eyes. But nothing some ply wood cant fix.",
"parent_id": ... | 1,760,373,637.163008 | ||
https://hackaday.com/2020/01/02/assistive-technolgy-switch-is-actuated-using-your-ear-muscles/ | Assistive Technolgy Switch Is Actuated Using Your Ear Muscles | Danie Conradie | [
"Medical Hacks"
] | [
"assistive technology",
"ear camera",
"game controller",
"hci",
"hearing",
"Human Computer Interface"
] | Assistive technology is extremely fertile ground for hackers to make a difference, because of the unique requirements of each user and the high costs of commercial solutions. [Nick] has been working on
Earswitch
, an innovative assistive tech switch that can be actuated using voluntary movement of the middle ear muscle.
Most people don’t know they can contract their middle ear muscle, technically called the tensor tympani, but will recognise it as a rumbling sound or muffling effect of your hearing when yawning or tightly closing eyes. Its function is actually to protect your hearing from loud sounds screaming or chewing. [Nick] ran a survey and found that 75% can consciously contract the tensor tympani and 17% of can do it in isolation from other movements. Using a cheap USB auroscope (an ear camera
like the one [Jenny] reviewed in November
), he was able to detect the movement using iSpy, an open source software package meant for video surveillance. The output from iSpy is used to control Grid3, a commercial assistive technology software package. [Nick] also envisions the technology being used as a control interface for consumer electronics via earphones.
With the proof of concept done, [Nick] is looking at ways to make the tech more practical to actually use, possibly with a CMOS camera module inside a standard noise canceling headphones. Simpler optical sensors like reflectance or time-of-flight are also options being investigated. If you have suggestions for or possible use case, drop by on the project page.
Assistive tech always makes for interesting hacks. We recently saw a
robotic arm
that helps people feed themselves, and the 2017 Hackaday Prize has an entire stage that was focused on
assistive technology
. | 16 | 9 | [
{
"comment_id": "6207071",
"author": "Ren",
"timestamp": "2020-01-02T20:10:38",
"content": "Wow!And I thought wiggling my ears was all I could do with them!",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6207077",
"author": "mark",
"timestamp": "2020-0... | 1,760,373,637.486589 | ||
https://hackaday.com/2020/01/02/tony-brooker-and-autocode-a-forgotten-tale/ | Tony Brooker And Autocode – The First High-level Language | Sven Gregori | [
"Biography",
"Featured",
"History",
"Original Art"
] | [
"alan turing",
"assembly",
"Autocode",
"cobol",
"compiler",
"computer history",
"computer science",
"FORTRAN",
"manchester baby",
"programming languages"
] | The field of computer science has undeniably changed the world for virtually every single person by now. Certainly for you as Hackaday reader, but also for everyone around you, whether they’re working in the field themselves, or are simply enjoying the fruits of convenience it bears. What was once a highly specialized niche field for a few chosen people has since grown into a discipline that not only created one of the biggest industry in modern times, but also revolutionized every other industry, some a few times over.
The fascinating part about all this is the relatively short time span it took to get here, and with that the privilege to live in an era where some of the pioneers and innovators, the proverbial giants whose shoulders every one of us is standing on, are still among us. Sadly, one of them, [Tony Brooker], a pioneer of the early programming language concept known as Autocode, passed away in November. Reaching the remarkable age of 94, the truly sad part however is that this might be the first time you hear his name, and there’s a fair chance you never heard of Autocode either.
But Autocode was probably the first high-level computer language, and as such played a fundamental role in the development of whatever you’re coding in today. So to honor the memory of [Tony Brooker], let’s remember the work he did with Autocode, and the leap in computer science history that it represented.
The Early Days
When it comes to ancient programming languages, Fortran and COBOL are always prime candidates to mention. Created in the late 1950s, these languages are surrounded by an almost mythical vibe. Developers much younger than the languages themselves, who have never saw a line of COBOL in the wild, will tell each other equally mythical stories about a distant relative who was once working with it in a laboratory or some other too-good-to-be-true environment.
Not that age really matters here; assembly is even older, and it is highly unlikely that it will ever lose its relevance. However, the difference is that assembly is a low-level language, while most other languages out there, including Fortran and COBOL, are high-level languages. Programming in assembly means writing in whatever
instruction set
a processor provides. Assembly languages are just handy mnemonics for the raw bits that the machine speaks. High-level languages on the other hand care a lot less about a processor’s instruction set, and are abstracting those details away to resonate more with the dynamics of the human mind instead.
Take a simple multiplication as example: in a typical high-level language, you’d simply write
a = b * c
, while in assembly, you’d write whatever the target processor itself knows about multiplication. You might load the multiplicands into dedicated registers and the CPU might have a multiplication instruction, or it might need to loop through a series of additions. You have to know how the chip works. In a high-level language, it’s going to be a compiler’s task to figure out how to do the actual multiplication and create the corresponding assembly code for it.
The Missing Link
So how does Autocode fit into all this, and what is it anyway? It was designed after assembly was invented, but before any high-level language has existed. Assembly itself was a rather
hot new topic
at this point in time, when people were still carving their bits by hand. Well, obviously not literally, but “programming” the computers of that time was tedious, non-intuitive, and error-prone work. Except for an early version of a compiler-like construct named Autocode, developed by [Alick Glennie].
One computer of the early days was the Manchester Mark 1, the direct successor of the
Baby
, and the machine [Alan Turing] was working with in the computer lab at Manchester University. It supposedly had a rather nasty instruction set that made the tedious nature of machine-language programming even worse, which was the first motivation to create Autocode: taming the machine.
The
University of Manchester’s
historic Mark 1 on the left, one rack of Baby on the right.
[Glennie]’s version of Autocode was a nice-syntax wrapper that remained otherwise machine-dependent, and we’d have to classify it as a low-level language. It wasn’t until the hero of our story, [Tony Brooker], came along to take a second shot at the idea of Autocode, that the first high-level language was written.
Legend says, one day, while on the way back to Cambridge where he was working as computer researcher, he popped into the Manchester University computer lab, introducing himself and his work to [Alan Turing]. Mutual interest in their work ensured, and [Tony Brooker] joined the computer lab to create his life’s work as part of his task to make the Mark 1 easier usable: designing an intuitive language with human-readable syntax that would hide away all the low-level nastiness, a language that wouldn’t require wasting countless hours of learning and deciphering each and every bit of the hardware, and ultimately turns the underlying hardware more or less into an irrelevant detail the programmer shouldn’t worry too much about. In short, it was planned as a true high-level language.
Starting development in 1954, the
Mark 1 Autocode
was ready the year after, and apart from the hardware independence, it also supported floating point arithmetic. While it had a few limitations with naming conventions and syntax, it was a big success in Manchester. [Tony Brooker] went on to continue developing the Autocode concept not only to other machines, but to the very concept of language creation itself. Taking Autocode further and further, he created the very first
compiler-compiler
in 1960, becoming virtually unstoppable with developing new languages.
Something To Build Upon
In a time where assembly was practically the epitome of convenience to operate a computer, the concepts of [Tony Brooker]’s version of Autocode took programming to the next level, and paved the way for a whole new realm of languages to come. And there was no one single Autocode language, just as there is no single, one assembly language. Autocode will probably be best thought of as a principle that has since evolved into the domain of compiled, high-level languages.
Unlike COBOL or Fortran, nobody codes in Autocode anymore. It’s a nearly forgotten relic of the past, regardless of the role it once played in the history of computer science. But the ideas that were embodied in Autocode live on. Without doubt, the creation of high-level programming languages was inevitable, yet it’s hard to fully appreciate today the work it took for pioneers like [Tony Brooker] to actually take the first steps towards it all those decades ago. Worth remembering. | 32 | 15 | [
{
"comment_id": "6207055",
"author": "Greg A",
"timestamp": "2020-01-02T19:17:27",
"content": "Cute language. Reminds me of my (very machine-dependent) language that I wind up re-inventing for a certain level of embedded work… I’ll describe it here in case anyone is interested, or anyways because ... | 1,760,373,637.357162 | ||
https://hackaday.com/2020/01/02/tales-and-advice-from-setting-up-a-product-line/ | Tales (and Advice) From Setting Up A Product Line | Donald Papp | [
"Crowd Funding"
] | [
"business",
"fulfillment",
"kickstarter",
"product line",
"production",
"security",
"shipping",
"usb key"
] | Making something that has to get into others’ hands involves solving a lot of different problems, many of which have nothing at all to do with actually building the dang things. [Conor Patrick] encountered them when he ran a successful Kickstarter campaign for an open-source USB security key that was not only shipped to backers, but also made available as an ongoing product for sale. There was a lot of manual and tedious work that could have been avoided, and so [Conor]
laid out all the things he wishes he had done when first setting up a product line
.
Turning these unprogrammed boards into finished products then shipping them is a big job.
If the whole process is a river, then the more “upstream” an issue is, the bigger its potential impact on everything that comes afterwards. One example is the product itself: the simplest and most easily managed product line is one that has only one product with no variations. That not only minimizes errors but makes supply, production, and shipping more straightforward. Striving for a minimum number of products and variations is also an example of something [Conor]
didn’t
do. In their crowdfunding campaign they offered the
SoloKeys
USB device — an implementation of the
FIDO2 authentication token
— as either USB-A or USB-C. There were also two types of key: NFC-capable (for tapping to a smartphone) and USB only. That is four products so far.
Offering keys in an unlocked state for those who want to tamper makes it eight different products. On top of that, they offered color choices which not only adds complexity to production, but also makes it harder to keep track of what everyone ordered. [Conor] also observed that the Kickstarter platform and back end are really not set up like a store, and it is clunky at best to try to offer (and manage) different products and variations from within it.
Another major point is fulfillment and in [Conor]’s opinion, unless the quantities are small, an order fulfillment company is worth partnering with. He says there are a lot of such companies out there, and it can be very time consuming to find the right one, but it will be nothing compared to the time and effort needed to handle, package, address, and ship several hundreds (or thousands!) of orders personally. His team did their own fulfillment for a total of over 2000 units, and found it a long and tedious process filled with hidden costs and challenges.
There’s good advice and background in [Conor]’s writeup, and this isn’t his first rodeo. He also
shared his thoughts on taking electronics from design to production
and the more general advice remains the same for it all: be honest and be open. Under-promise and over-deliver, especially when it comes to time estimates. | 5 | 3 | [
{
"comment_id": "6207094",
"author": "Hunter Long",
"timestamp": "2020-01-02T20:55:19",
"content": "Hey Conor, it’s Hunter from back in the AMP lab days :) Awesome work on the SoloKey, and great product line advice. I learned a lot reading it!",
"parent_id": null,
"depth": 1,
"replies": ... | 1,760,373,636.981775 | ||
https://hackaday.com/2020/01/02/ask-hackaday-how-do-you-keep-the-3d-printer-from-becoming-ewaste/ | Ask Hackaday: How Do You Keep The 3D Printer From Becoming EWaste | Jenny List | [
"3d Printer hacks",
"Ask Hackaday",
"Original Art"
] | [
"3d printer",
"ewaste",
"junk",
"junk bin"
] | One thing we sometimes forget in our community is that many of the tecniques and machines that we take for granted are still something close to black magic for many outsiders. Here’s a tip: leave a 3D printer running next time you take a group of visitors round a hackerspace, and watch their reaction as a Benchy slowly emerges from the moving extruder. To us it’s part of the scenery, but to them it’s impossibly futuristic and their minds are blown.
Just because something
says
it’s a Prusa i3, doesn’t mean it
is
a Prusa i3.
Nearly 15 years after the dawn of the RepRap project we have seen a huge advancement in the capabilities of affordable 3D printers, and now a relatively low three-figure sum will secure a machine from China that will churn out prints whose quality would amaze those early builders. We’ve reached the point in our community at which many people are on their third or fourth printer, and this has brought with it an unexpected side-effect. Where once a hackerspace might have had a single highly prized 3D printer, now it’s not unusual to find a pile of surplus older printers on a shelf. My hackerspaces both have several, and it’s a sight I’ve frequently seen on my travels around others. Perhaps it’s a sign of a technology maturing when it becomes ewaste, and thus it seems affordable 3D printing has matured.
Printer History Told Through The Medium Of Junk Piles
My hackerspace isn’t the only one with a few spare 3D printers! Ultimaker stash photo: Mendel Mobach
You can tell a lot about a product by how long it remains in use, for example a much higher percentage of Volkswagen Golfs have survived for three decades than have Yugo 55s. Thus a look at these piles of old printers is to look at which models turned out to be the stars and which the lemons. There are several main strands among them, each one representing a different set of failed dreams. First among them are the pioneers, a Makerbot Cupcake or perhaps a RepRap Darwin or Mendel. We even know of one space with a working Cupcake, but these aren’t machines you would use in 2019. Instead they represent the days when 3D printing was still a novelty even to us. If you think of the first machine you saw, perhaps it will be here.
Then there are the surprises, decent workhorses in their day that could still deliver a creditable result but which have simply been bypassed. It was a shock earlier in the year to see a pile of Ultimakers lying idle for instance, but perhaps I needed reminding that it was no longer 2015.
By far the most numerous though are the next group, knock-offs, proving that merely selling something as a Prusa clone does not make it a Prusa. It’s interesting though that not all clones were of low quality, I can think of more than one space still happily using years-old WanHao Duplicators, clones of the Makerbot Replicator.
Finally it’s a constant among hackerspaces that someone will have bought a delta printer and inevitably found it to be problematic. Is it a desire to be different or merely a fondness for printing vases that drives it, but if I had to guess which printer would be gathering dust it would be someone’s delta project.
What Can You
Do
with all This Junk?
So we’ve exposed a typical hackerspace junk pile as a potted history of failed desktop 3D printing endeavour, but as well as that it’s both a significant problem and an opportunity. A problem because while it has become a matter of ewaste the 3D printers themselves are still perceived as having value — but value that can only be realized if they do something other than sit on a junk pile. An opportunity because they still contain the basis of a CNC machine that is sitting idle.
If we can rid ourselves of the view that an old 3D printer is sacrosanct then we can make something of them, turn them into the basis of something else. We’ve all at times
amassed piles of junk before realising that we’ve made a mistake
, so there’s no shame in taking a fresh look at that printer pile.
The WanHao Duplicator that’s still one of the workhorse printers at MK Makerspace.
At its most basic, a redundant 3D printer is a pile of parts just waiting to be dismantled. Slides, stepper motors, extrusions, and the associated electronics. It’s questionable whether whatever was the cutting edge in extruders and control boards circa 2012 could find a use in 2019, but the rest should find ready homes in other projects. To dismantle a printer though is perhaps to lose sight of its main event. A ready-made CNC mechanism with generous X, Y, and Z axes and a ready-to-go controller should be something that presents endless possibilities.
Attaching a mini router or an engraving laser to it is something of a done deal, but what else could you do? Make chocolate and fondant extruders with syringes and servos, and print confectionery? Attach an LED for some 3D-light painting? One-off art project or wacky tool, how have you repurposed your disused printer to keep it from gathering dust.
Whatever you think of for your surplus 3D printers, perhaps in all this there’s another story. Our community didn’t invent the 3D printer, but we’ve certainly taken it as our own and run with it. If we’ve reached the point at which they have finally matured, then in part that success belongs to us, to those hackers who have pushed forward their design. We can feel proud of that pile of surplus older printers, because they and the $200 Chinese machine that replaced them represent a 15-year success story from our community. The question is, where will they go in the next 15 years? | 94 | 26 | [
{
"comment_id": "6206978",
"author": "RW ver 0.0.1",
"timestamp": "2020-01-02T15:32:07",
"content": "There’s plenty of people around who would be happy to buy a used one for ~$100… but the few sellers around seem to think that however outdated it is, it’s worth $300-ish … despite as mentioned, somet... | 1,760,373,637.618794 | ||
https://hackaday.com/2020/01/02/unlocking-sim-cards-with-a-logic-analyzer/ | Unlocking SIM Cards With A Logic Analyzer | Tom Nardi | [
"Cellphone Hacks",
"Security Hacks"
] | [
"logic analyzer",
"sim card",
"sniffing",
"unlock"
] | [Jason Gin] wanted to reuse the SIM card that came with a ZTE WF721 wireless terminal he got from AT&T, but as he expected, it was locked to the device. Unfortunately, the terminal has no function to change the PIN and none of the defaults he tried seemed to work. The only thing left to do was
crack it open and sniff the PIN with a logic analyzer
.
This project is a fantastic example of the kind of reverse engineering you can pull off with even a cheap logic analyzer and a keen eye, but also perfectly illustrates the fact that having physical access to a device largely negates any security measures the manufacturer tries to implement. [Jason] already knew what the SIM unlock command would look like; he just needed to capture the exchange between the WF721 and SIM card, find the correct byte sequence, and look at the bytes directly after it.
Finding the test pads on the rear of the SIM slot, he wired his DSLogic Plus logic analyzer up to the VCC, CLK, RST, and I/O pins, then found a convenient place to attach his ground wire. After a bit of fiddling, he determined the SIM card was being run at 4 MHz, so he needed to configure a baud rate of 250 kbit/s to read the UART messages passing between the devices.
Once he found the bytes that signified successful unlocking, he was able to work his way backwards and determine the unlock command and its PIN code. It turns out the PIN was even being sent over the wire in plain text,
though with the way security is often handled these days
, we can’t say it surprises us. All [Jason] had to do then was put the SIM in his phone and punch in the sniffed PIN when prompted.
Could [Jason] have just run out to the store and picked up a prepaid SIM instead of cracking open this wireless terminal and sniffing its communications with a logic analyzer? Of course. But where’s the fun in that? | 20 | 5 | [
{
"comment_id": "6206954",
"author": "Morso",
"timestamp": "2020-01-02T13:08:51",
"content": "All communication to SIM card is “plain text”. No encryption or authentication, etc. You can sniff everything.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "620696... | 1,760,373,637.715023 | ||
https://hackaday.com/2020/01/02/roll-the-bones-chernobyl-style/ | Roll The Bones Chernobyl Style | Dan Maloney | [
"Misc Hacks"
] | [
"entropy",
"Fallout",
"geiger",
"nixie",
"radiation",
"rng",
"uranium",
"usb"
] | We’re suckers for the
Fallout
aesthetic, so anything with a post-apocalyptic vibe is sure to get our attention. With a mid-century look, Nixie tubes, a brushed metal faceplate, and just a touch of radioactivity,
this quantum random number generator
pushes a lot of design buttons, and it pushes them hard.
Charmingly named “Chernobyl Dice”, this little gadget comes to us from [Nathan Griffith], and appears to be one of those “Why not?” builds we love so much. The heart of any random number generator is a source of entropy, for which [Nathan] chose to use six slightly radioactive uranium glass marbles. Those feature prominently in the front panel of the device, occasionally made to fluoresce with a few UV LEDs just because it looks cool. A Geiger tube inside the case is used to look for decay events from the marbles every millisecond. After some adjustment for the bias toward zeroes due to the relative rarity of decay events, the accumulated bits are displayed on eight Nixies. The box can be set to generate a stream of random numbers up to 31 bits long and send it over a USB port, or make random throws of a die with a settable number of sides. And when it’s not doing random stuff, it can just be a cool Nixie clock.
There are lots of ways to generate the entropy needed for truly random number generation, from
a wall of lava lamps
to
bubbles in a fish tank
. They’ve all got style, but something about this one just works.
[via
r/DIY
] | 18 | 6 | [
{
"comment_id": "6206935",
"author": "ewrfrew",
"timestamp": "2020-01-02T11:08:44",
"content": "power, why power are stil from wall ?;)",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6206974",
"author": "DainBramage",
"timestamp": "2020-01-02... | 1,760,373,637.985563 | ||
https://hackaday.com/2020/01/01/hacking-an-arduino-nfc-reader-with-webusb/ | Hacking An Arduino NFC Reader With WebUSB | Al Williams | [
"Arduino Hacks"
] | [
"arduino",
"Arduino Leonardo",
"leonardo",
"NFC",
"WebUSB"
] | When [gdarchen] wanted to read some NFC tags, he went through several iterations. First, he tried an Electron application, and then a client-server architecture. But his final iteration was to make
a standalone reader with an Arduino and use WebUSB
to connect to the application on the PC.
This sounds easy, but there were quite a few tricks required to make it work. He had to hack the board to get the NFC reader’s interrupt connected correctly because he was using a Leonardo board. But the biggest problem was enabling WebUSB support. There’s a library, but you have to change over your Arduino to use USB 2.1. It turns out that’s not hard, but there’s a caveat: Once you make this change you will need the WebUSB library in all your programs or Windows will refuse to recognize the Arduino and you won’t be able to easily reprogram it.
Once you fix those things, the rest is pretty easy. The PC side uses node.js. If you back up a level in the GitHub repository, you can see the earlier non-Arduino versions of the code, as well.
If you want to understand all the logic that went into the design, the author also included a
slide show
that discusses the three versions and their pros and cons. He did mention that he wanted a short-range solution so barcodes and QR codes were out. He also decided against RFID but didn’t really say why.
NFC business cards
are a thing. You can also use them to catch some
public transportation
. | 13 | 5 | [
{
"comment_id": "6206918",
"author": "tomás zerolo",
"timestamp": "2020-01-02T09:05:32",
"content": "Well, I didn’t know, I must admit.I looked up what WebUSB is, and heck, no. Why let the browser, arguably the most insecure and compromised app in my whole box (after all, it’s picking up all the gar... | 1,760,373,637.822495 | ||
https://hackaday.com/2020/01/01/a-new-high-performance-camera-that-detects-single-photons/ | A New High-Performance Camera That Detects Single Photons | Sharon Lin | [
"Science"
] | [
"camera",
"nanowires",
"nasa",
"research",
"space"
] | There may soon be breakthroughs in the search for dark matter. A new publication in
Optics Express
reveals a camera consisting of superconducting nanowires capable of detecting single photons
, a useful feature for detecting light at the furthest ends of the infrared band. The high-performance camera, developed by the National Institute of Standards and Technology (NIST), boasts some of the best performing photon counters in the world in terms of speed, efficiency, and color detection. The detectors also have some of the lowest dark count rates of any photon sensor, resisting false signals from noise.
The size of the detectors comes out to 1.6mm on each side, packed with 1024 sensors for high resolution imagery and fabricated from silicon wafers cut into chips. The nanowires are made from tungsten and silicon alloy with leads made from superconducting niobium.
In order to prevent the sensors from overheating, a readout architecture was used based on a previous demonstration on a smaller camera with 64 sensors adding data from rows and columns. The research has been in collaboration with the National Aeronautics and Space Administration (NASA), which seeks to include the camera in the Origins Space Telescope project.
The eventual goal is to use the arrays to analyze chemical compositions of planets outside of our solar system. By observing the absorption spectra of light passing through an exoplanet’s atmosphere, information can be gathered on the elements in the atmosphere. Currently, large-area single-photon counting detector arrays don’t exist for measuring the mid- to far-infrared signatures, the spectrum range for elements that may indicate signs of life. While fabrication success is high, the efficiency of the detectors remains quite low, although there are plans to extend the current project into an even bigger camera with millions of sensors.
In addition to searching for chemical life on other planets, future applications may include recording measurements to confirm the existence of dark matter.
[Thanks Qes for the tip!] | 15 | 6 | [
{
"comment_id": "6206884",
"author": "Pat",
"timestamp": "2020-01-02T03:44:22",
"content": "To be clear, the fact that it can detect single photons isn’t exactly groundbreaking. Your eyes can detect single photons – and the quantum efficiency (how *often* it detects a single photon) isn’t really any... | 1,760,373,637.777026 | ||
https://hackaday.com/2020/01/01/catapult-your-best-wishes-with-this-3d-printable-card/ | Catapult Your Best Wishes With This 3D-Printable Card | Jenny List | [
"Toy Hacks",
"Weapons Hacks"
] | [
"catapult",
"leonardo da vinci",
"toy"
] | It’s the season to be surrounded by greeting cards of all shapes and sizes from friends old and new. News of their families and achievements, reminders that they exist, and a pile of cards to deal with sometime in January. Wouldn’t it be great if you could send something with a little more substance, something your friends would remember, maybe even hang on to?
[Brian Brocken]’s
3D-printed Da Vinci catapult kit
may not fill that niche for everyone, but we can guarantee it will be a talking point. The Da Vinci catapult design uses a pair of springs similar to an archer’s bow, to unwind a pair of ropes and thus turn the shaft upon which the catapult shaft itself is fitted. All these components are mounted in a single piece with sprues similar to an injection moulded model kit, allowing the whole to easily be posted in an envelope.
The parts are all available to print separately
among the files on the Thingiverse page
for those with no need to mail them. For the casual spectator he’s made a YouTube video that we’ve placed below the break, detailing the design and build process as well as showing the device in use. | 12 | 3 | [
{
"comment_id": "6206852",
"author": "RW ver 0.0.1",
"timestamp": "2020-01-02T00:12:29",
"content": "How many of the old school spring steel cycle clips (For your pants/trouser leg) do you think I’d have to laminate together to replace the spring with before it will put a .177 BB through a 2×4?",
... | 1,760,373,638.087066 | ||
https://hackaday.com/2020/01/01/explore-this-3d-world-rendered-in-ascii-art/ | Explore This 3D World Rendered In ASCII Art | Sharon Lin | [
"Games"
] | [
"ascii art",
"RPG",
"web games"
] | Pixelated RPGs are pretty standard in games like Legend of Zelda and Pokemon, but have you ever seen anything like
ASCIICKER
? It’s a full-color three-dimensional world rendered with ASCII art and playable in your browser.
For the time being, the game exists as an experiment. There’s no storyline or goals other than exploring the world, although you can meet up with (or follow) others exploring the game — although all of the sprites look the same, so it may be difficult to have interactions. The game was created by [Gumix] and built entirely in JavaScript without using any other game engines.
All of the previous iterations have also
been published online
and are accessible by adding X1 up to X13 to the end of the URL. With game development beginning in 2017, it has since been through a considerable amount of change. There’s an entire
subreddit
dedicated to the game with regular updates from the creator on the development of an open-source dev tool for building new levels and features for the environment. The current engine is capable of rendering objects as thin as fences as well as reflections in bodies of water.
You can
try out the game for yourself
and see what you think! | 19 | 10 | [
{
"comment_id": "6206810",
"author": "dkuku",
"timestamp": "2020-01-01T21:24:35",
"content": "Reminds me a bit of aalib and caca",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6206814",
"author": "Waterfowl",
"timestamp": "2020-01-01T21:35:52",
"co... | 1,760,373,638.21723 | ||
https://hackaday.com/2020/01/01/reducing-the-risk-of-flying-with-hydrogen-fuels/ | Reducing The Risk Of Flying With Hydrogen Fuels | Sharon Lin | [
"green hacks",
"Transportation Hacks"
] | [
"aviation",
"hydrogen fuel",
"transportation"
] | Flight shaming is the hot new thing where people who take more than a handful of trips on an airplane per year are ridiculed for the environmental impact of their travels. It’s one strategy for making flying more sustainable, but it’s simply not viable for ultimately reducing the carbon impact that the airline industries have on the environment.
Electric planes are an interesting place to look for answers. Though carbon-free long haul travel is possible, it’s not a reality for most situations in which people travel today. Current battery technology can’t get anywhere near the energy density of fossil fuels and larger batteries aren’t an option since every pound matters when designing aircraft.
Even with land travel and electric grids improving in their use of renewables and electric power, aviation tends to be difficult to power with anything other than hydrocarbons. Student engineers in the AeroDelft program in the Netherlands have created
Project Phoenix
to develop an aircraft powered by a liquid hydrogen fuel cell, producing a primary emission of water vapor. So it
is
an electric plane, but leverages the energy density of hydrocarbons to get around the battery weight problem.
While the project may seem like an enormous reach peppered with potential safety hazards, redundant safety features are used such as sensors and vents in case of a hydrogen leakage, as well as an electric battery in case of failure. Hydrogen produced three times more energy per unit than kerosene, but is six times the volume in gas form and requires cumbersome compression tanks.
Even though hydrogen fuel only produces water vapor as a byproduct, it can still cause greenhouse effects if it is released too high and creates clouds. The team is exploring storage tanks for slow release of the water vapor at more optimal altitudes. On top of that, most hydrogen is produced using steam methane reforming (SMR), creating up to 150g of greenhouse gases per kWh, and electrolysis tends to be more costly and rarely carbon neutral. Alternatives such as solar power, biofuels, and
electric power
are looking to make headwind as well, but the technology is still far from perfected.
While it’s difficult to predict the success of the project so early on, the idea of reducing risk in hydrogen fuels may not be limited to a handful of companies for very long. | 91 | 17 | [
{
"comment_id": "6206776",
"author": "Nate B",
"timestamp": "2020-01-01T18:04:19",
"content": "Sailing ships were carbon-free long-distance travel, centuries before our obsession with fossil fuels began.What changed is we got impatient. And I think that’s been bad for our health in a lot of ways.Liv... | 1,760,373,638.504136 | ||
https://hackaday.com/2020/01/01/happy-50th-birthday-to-all-you-epoch-birthers/ | Happy 50th Birthday To All You Epoch Birthers | Jenny List | [
"clock hacks",
"Featured",
"History",
"Interest",
"Original Art"
] | [
"timing",
"unix",
"unix epoch"
] | Good morning everyone, and what a lovely start to the new year it is, because it’s your birthday! Happy birthday, it’s your 50th! What’s that you say, you aren’t 50 today? (Looks…) That’s what all these internet databases say, because you’ve spent the last decade or so putting 1970-01-01 as your birth date into every online form that doesn’t really need to know it!
It’s been a staple for a subset of our community for years, to put the UNIX epoch, January 1st 1970, into web forms as a birth date. There are even rumours that some sites now won’t accept that date as a birthday, such is the volume of false entries they have with that date. It’s worth taking a minute though to consider UNIX time, some of its history and how its storage has changed over the years.
Don’t Use Up That 32 Bit Int Too Quickly
How do you turn a 1960s minicomputer into a clock? Digital pdp8f.jpg: Simon Claessen [
CC BY-SA 3.0
]
Most readers will be familiar with the UNIX timestamp that the date command will return on UNIX-like operating systems. It’s an integer value representing the number of whole seconds that have elapsed since January 1st 1970, and it’s easy enough to write a little script that scrolls it up the screen so you can watch it increment second by second. But the interesting things about it are that the epoch date preceded its inception by several years, and the earliest UNIX versions used a rather different timing system.
We’re used to generating any clock signal we please using any of a huge number of available clock chips. If we need an odd frequency, there will be a PLL chip somewhere that can do it. In the early 1970s though the designers of the DEC minicomputers used by those primordial UNIX developers did not have that luxury, as complex clock generation would have required costly extra logic chips. The earliest UNIX time was thus measured in terms of the American mains power frequency, 60ths of a second with an epoch at the start of 1971. Since a 32 bit number at that rate would have meant a very short time before roll-over it was decided to use seconds instead with an epoch at the start of the decade. The latest distributions might have switched to using a 64-bit integer because the original 32-bit one would roll over in 2038, but otherwise the timing scheme remains unchanged.
Face It, We’re All Growing Older One Second At A Time
The 50-year anniversary, whether real or assumed, hides another impact of that early UNIX. For our youngest readers it’s possible that the start of the 1970s now represents as remote a date as possible, but for many adults it has still been possible to cling to the notion that it’s not too long ago even if we weren’t personally around to see it. The five-decade mark is a definitive point that puts it firmly in the historical, and should remind us that
UNIX is no longer the relative new kid it might have been when we first used it
.
You can still get away with claiming it for a fake birthday (at least for a a few more decades) perhaps it’s time to reflect that much of the technology we like to think of as cutting-edge and exciting is in fact now mature and middle-aged. It’s likely we’ll be still measuring time in some way from the same UNIX epoch in a century’s time, and by then how shall we express a fake birthday? | 19 | 11 | [
{
"comment_id": "6206749",
"author": "JWhitten",
"timestamp": "2020-01-01T15:15:29",
"content": "I’m one of those old-timers who remembers 1970 personally. My fake birthday however is on a different date. But great article, and the epoch would be a great choice.",
"parent_id": null,
"depth":... | 1,760,373,638.151836 | ||
https://hackaday.com/2020/01/01/magnetic-circuits-are-more-attractive-than-breadboarding/ | Magnetic Circuits Are More Attractive Than Breadboarding | Kristina Panos | [
"classic hacks"
] | [
"circuit blocks",
"copper tape",
"magnets",
"neodymium magnet"
] | Let’s face it, breadboarding can be frustrating, even for advanced electronics wizards. If you have an older board, you could be dealing with loose tie points left from large component legs, and power rails of questionable continuity. Conversely, it can be hard to jam just-made jumper wires into new boards without crumpling the copper. And no matter what the condition of the board is, once you’ve plugged in more than a few components, the circuit becomes hard to follow, much less troubleshoot when things go pear-shaped.
In the last twenty years or so, we’ve seen systems like Snap Circuits and Little Bits emerge that simplify the circuit building process by making the connections more intuitive and LEGO-like than even those 160-in-1 kits where you shove component legs between the coils of tight little springs. You will pay handsomely for this connective convenience. But why should you?
Just make your own circuit blocks with cardboard, magnets, and copper tape
. It should only cost about 10¢ each, as long as you source your magnets cheaply.
[rgco] gives the lowdown on building a minimal set of 23 component and connector blocks using 100 magnets. He’s got 11 example circuits to get you started, and some example videos of more advanced circuits that got tacked up after the break.
This method of making the circuit look more like the schematic may be the best way for the visually-inclined to learn electronics.
But the best way to learn electronics depends on where you’re coming from
. | 16 | 11 | [
{
"comment_id": "6206735",
"author": "shinsukke",
"timestamp": "2020-01-01T12:54:14",
"content": "I’ll just stick with my breadboard for(ever) now, thanks for the new….er idea?",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6206739",
"author": "Prolly",
... | 1,760,373,638.042538 | ||
https://hackaday.com/2020/01/01/building-a-giant-meta-clock-made-of-smaller-clocks/ | Building A Giant Meta-Clock Made Of Smaller Clocks | Sharon Lin | [
"clock hacks",
"Microcontrollers"
] | [
"analog clock",
"digital clock"
] | Have any last-minute projects you finished just before the end of the decade? To help pass the time, [Erich Styger] decided to build a
meta digital clock
made up of 24 individual analog clocks, the perfect item to help welcome in the new year. The stepper clock is controlled by a network of LPC microcontrollers, displaying the time and room temperature, as well as several aesthetically pleasing loading animations.
Each clock operates from a 5 V USB power bank drawing less than 2 A for the full 24-clock setup. The meta-clock resides in a laser cut enclosure, with 3D printed hands telling the time. While having one board per clock would be easier to implement, [Erich] decided to use one board per four clocks arranged in rows to save on costs. The arrangement fixes the distance between clocks, though [Erich] also made the clock size slightly smaller to compensate.
The ‘stepper’ part of the stepper clock uses a 360 degree version of the VID28 stepper motor to reduce the height of the design and the cost of the project. Apart from the X12.017 driver silently driving the motors, the stepper motors also conveniently only need a ‘direction’ and ‘step’ pin, reducing the pin count needed for the microcontroller. Neodymium magnets and hall effect sensors are used for tracking the position of the hands as the clocks move, with the magnets embedded into the clock hands.
As for communication, rather than use the common I2C protocol, the more robust RS-485 was selected. A master coordinates all of the clocks using the bus, providing a command line interface. The master is also able to communicate with the host PC over USB to maintain RTC time.
During the software development phase, [Erich] made use of the SEGGER J-Link EDU mini CLI for keeping track of information about the driver and each individual stepper motor. The software controlling the motors is written in C, with boards running FreeRTOS. The stepping is handled with a timer interrupt, but because the LPC845 doesn’t have enough timer channels, all of the functionality is done within a single channel. This results in plenty of interrupt handlers, flags, and callbacks across the code, which makes for some good fun.
Speaking of clocks, check out some of our other past clock hacks, including this
mini-VFD clock
and this fun
LED matrix clock
(it lets you play Tetris!)
https://www.youtube.com/watch?v=WsxtxT9oboM | 18 | 9 | [
{
"comment_id": "6206718",
"author": "JWhitten",
"timestamp": "2020-01-01T09:06:07",
"content": "That is actually cool. I’ve seen a lot of clock variations, but this one is pretty clever, IMO.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6206850",
... | 1,760,373,638.277384 | ||
https://hackaday.com/2019/12/31/poe-powers-christmas-lights-but-opens-up-so-much-more/ | PoE Powers Christmas Lights, But Opens Up So Much More | Jenny List | [
"LED Hacks",
"Network Hacks"
] | [
"Art-Net",
"holiday light show",
"led",
"network",
"PoE",
"power over ethernet"
] | Addressable LEDs are a staple of homemade Christmas decorations in our community, as is microprocessor control of those LEDs. So at first sight [Glen Akins]’
LED decorated Christmas tree
looks pretty enough, but isn’t particularly unusual. But after reading his write-up you’ll discover there’s far more to the project than meets the eye, and learn a lot about the technologies behind it that has relevance far beyond a festive light show.
The decoration is powered exclusively from power-over-Ethernet, with a PIC microcontroller translating
Art-Net
DMX-over-Ethernet packets into commands for the LED string. The control board is designed from the ground up and includes all the PoE circuitry, and the write-up gives a very thorough introduction to this power source that takes the reader way beyond regarding PoE as simply another off-the-shelf black box. Along the way we see all his code, as well as learn a few interesting tidbits such as the use of a pre-programmed EEPROM containing a unique MAC address.
So if your house has CAT5 wiring and you want an extra dimension to your festive splendour, you’ve officially got a whole year to build your own version. He’s featured here before, with
his buzzer to break the Caps Lock habit
. | 12 | 6 | [
{
"comment_id": "6206708",
"author": "Ostracus",
"timestamp": "2020-01-01T06:52:38",
"content": "What is the cost on addressable strings vs regular strings?",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6206710",
"author": "Glen Akins",
"tim... | 1,760,373,638.331929 | ||
https://hackaday.com/2019/12/31/flip-phones-are-making-a-comeback/ | Flip Phones Are Making A Comeback | Sharon Lin | [
"Phone Hacks"
] | [
"flip phone",
"retro",
"smartphone"
] | If you’re the kind of person who hates this new generation of smartphone users and longs for a nostalgic past, you’re not far from the new target demographic for many commercial phone manufacturers. Major phone companies like Motorola and Huawei have been developing foldable versions of conventional smartphone designs, intended to be more versatile while maintaining the same functionality as their less flexible counterparts.
It’s certainly gimmicky, but phones like the Samsung Galaxy Fold,
the Motorola Razr
, and the Huawei MateX are elegant from an engineering perspective. Developing a seamless interface experience, maximizing surface area for functionality, and maintaining the same nostalgic flip phone aesthetic while making use of familiar smartphone features isn’t an easy design process.
Motorola RAZR hinge
shown by CNET’s Patrick Holland
during a tour of their labs.
For the Razr, a hinge system that takes up about a third of the phone’s internal space allows the OLED display to have no noticeable binder line. Rather than curving like a piece of paper, it forms a teardrop shape that prevents the screen from creasing and being damaged. Springs and pistons below the surface move small places underneath where the user will be tapping – folded in, the plates slide away. It’s an interesting effect, although as you can see in the banner image, it doesn’t quite achieve optically flat perfection.
In order to ensure that the screen doesn’t overheat as it bends, it is made up of microlayers sandwiched together. To balance weight, the circuits and battery is split into two, operating on each half of the device, an unusual design choice for smartphones. Placement of the array of radios and antennas is also a challenge since they can’t be too close to each other or the processor, which can interfere with signal transmission.
Other devices like
the Royale Flexpai
are more so proof-of-concepts making use of flexible screens and batteries, rather than capturing the aesthetics of a flip phone generation — but who doesn’t want their smartphone to unfold into a tablet when needed? The future of smartphone technology is looking interesting, and we’ll be sure to see even more iterations of flexible displays in the near future. | 34 | 27 | [
{
"comment_id": "6206692",
"author": "Reactive Light",
"timestamp": "2020-01-01T03:08:03",
"content": "Absolutely ridiculous.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6206767",
"author": "P Beattie",
"timestamp": "2020-01-01T16:48:05",
... | 1,760,373,638.64569 | ||
https://hackaday.com/2019/12/31/macro-photography-with-industrial-lenses/ | Macro Photography With Industrial Lenses | Lewin Day | [
"digital cameras hacks"
] | [
"camera lens",
"dslr",
"lens",
"macro photography",
"sony",
"sony camera"
] | Line scan cameras are advanced devices used for process inspection tasks in industrial applications. Used to monitor the quality of silicon wafers and other high-accuracy tasks, they’re often outfitted with top-quality optics that are highly specialised. [Peter] was able to get his hands on a lens for a line-scan camera,
and decided to put it to work on some macro photography instead.
Macro image taken with the hacked lens.
Judging by
the specs found online,
this is a fairly serious piece of kit. It easily competes with top-shelf commercial optics, which is what piqued [Peter]’s interest in the part. Being such a specialised piece of hardware, you can’t just cruise over to eBay for an off-the-shelf adapter. Instead, a long chain of parts were used to affix this lens to a Sony AIII DSLR, converting from threaded fittings to a Nikon mount and then finally to Sony NEX mount.
Further work involved fitting an aperture into the chain to get the lens as close as possible to telecentric. This improves the lens’s performance for certain tasks, and makes focus stacking macro shots more readily achievable –
something we’ve seen [Peter] tinker with before
.
You never know what you might find when sorting through surplus industrial gear, could could score some high-performance hardware if you know where to look. It’s always great to see a cheap find become a useful instrument in the hacker toolbox! | 11 | 6 | [
{
"comment_id": "6206674",
"author": "cliff claven",
"timestamp": "2020-01-01T00:26:26",
"content": "Excellent reuse, and excellent job recognizing good kit when found. The lens is intended for telecentric use, and I am envious.",
"parent_id": null,
"depth": 1,
"replies": []
},
{
... | 1,760,373,638.5685 | ||
https://hackaday.com/2019/12/31/foam-board-old-electronics-and-imagination-make-movie-magic/ | Foam Board, Old Electronics, And Imagination Make Movie Magic | Dan Maloney | [
"Misc Hacks"
] | [
"decoration",
"Fallout",
"film",
"movie",
"props",
"retro",
"sci-si",
"sets",
"tdd",
"tty",
"vintage"
] | When it comes to building sets and props for movies and TV, it’s so easy to get science fiction wrong – particularly with low-budget productions. It must be tempting for the set department to fall back on the “get a bunch of stuff and paint it silver” model, which can make for a tedious experience for the technically savvy in the audience.
But low-budget does not necessarily mean low production values if the right people are involved. Take
[Joel Hartlaub]’s recent work building sets for a crowdfunded sci-fi film
called
Infinitus
. It’s a post-apocalyptic story that needed an underground bunker with a
Fallout
vibe to it, and [Joel] jumped at the chance to hack the sets together. Using mainly vintage electronic gear and foam insulation boards CNC-routed into convincing panels, he built nicely detailed control consoles for the bunker. A voice communicator was built from an old tube-type table radio case with some seven-segment displays, and the chassis of an old LCD projector made a convincing portable computer terminal. The nicest hack was for the control panel of the airlock door. That used an old TDD, or
telecommunications device for the deaf
. With a keyboard and a VFD display, it fit right into the feel of the set. But [Joel] went the extra mile to make it a practical piece, by recording the modulated tones from the acoustic coupler and playing them back, to make it look as if a message was coming in. The airlock door looks great too.
Like many hacks, it’s pretty impressive what you can accomplish with a deep junk pile and a little imagination. But if you’ve got a bigger budget and you need some computer displays created,
we know just the person for the job
.
[Matt] tipped us off to this one. Thanks! | 11 | 5 | [
{
"comment_id": "6206657",
"author": "Ostracus",
"timestamp": "2019-12-31T21:52:03",
"content": "Virtual sets and production are the “in” thing.https://www.onsetfacilities.com/virtual-production-in-unreal-engine/",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id":... | 1,760,373,639.082736 | ||
https://hackaday.com/2019/12/31/a-soft-robotic-insect-that-survives-the-fly-swatter/ | A Soft Robotic Insect That Survives The Fly Swatter | Sharon Lin | [
"Robots Hacks"
] | [
"microcontroller",
"research",
"robotic insect"
] | Swarms of robotic insects incapable of being swatted away may no longer be the product of science fiction and
Black Mirror
episodes. A team from EPFL’s School of Engineering has developed an insect propelled at 3 cm/s, dubbed
the DEAnsect
.
What makes this robot unique is its exceptional robustness. Two versions of the robot were initially developed, one tethered with ultra-thin wires capable of being
squashed with a shoe
without impacting its functions and the second fully wireless and autonomous. The robot weighs less than 1 gram and is equipped with a microcontroller and photodiodes to recognize black and white patterns.
The insect is named for its dielectric elastomer actuators (DEAs), an artificial muscle that propels it with vibrations and enables it to move lightly and quickly.
The DEAs are made of an elastomer membrane wedged between soft electrodes that are attracted to each other when a voltage is applied, compressing the membrane. The membrane returns to its original shape when the voltage is turned off. Movement is generated by switching the voltage on and off over 400 times per second. The team reduced the thickness of the membranes and developed soft, highly conductive electrodes only several molecules thick using nanofabrication techniques. They plan on fitting even more sensors and emitters to allow the insects to communicate directly with one another for greater swarm-like activity. | 7 | 4 | [
{
"comment_id": "6206617",
"author": "RW ver 0.0.1",
"timestamp": "2019-12-31T18:08:39",
"content": "We know, Al told us last week :-Dhttps://hackaday.com/2019/12/23/robot-insect-survives-swatting/",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6206650",
... | 1,760,373,638.712995 | ||
https://hackaday.com/2019/12/31/fail-of-the-week-ambitious-vector-network-analyzer-fails-to-deliver/ | Fail Of The Week: Ambitious Vector Network Analyzer Fails To Deliver | Dan Maloney | [
"Fail of the Week"
] | [
"AD8302",
"fail of the week",
"filter",
"fotw",
"harmonics",
"RF",
"thesis",
"vector network analyzer",
"vna"
] | If you’re going to fail, you might as well fail ambitiously. A complex project with a lot of subsystems has a greater chance of at least partial success, as well as providing valuable lessons in what not to do next time. At least that’s the lemonade [Josh Johnson] made from
his lemon of a low-cost vector network analyzer
.
For the uninitiated, a VNA is a versatile test instrument for RF work that allows you to measure both the amplitude and the phase of a signal, and it can be used for everything from antenna and filter design to characterizing transmission lines. [Josh] decided to port a lot of functionality for his low-cost VNA to a host computer and concentrate on the various RF stages of the design. Unfortunately, [Josh] found the performance of the completed VNA to be wanting, especially in the phase measurement department. He has a complete analysis of the failure modes in
his thesis
, but the short story is poor filtering of harmonics from the local oscillator, unexpected behavior by the AD8302 chip at the heart of his design, and calibration issues. Confounding these issues was the time constraint; [Josh] might well have gotten the issues sorted out had the clock not run out on the school year.
After reading through [Josh]’s description of his project, which was a final-year project and part of his thesis, we feel like his rating of the build as a failure is a bit harsh. Ambitious, perhaps, but with
a spate of low-cost VNAs
coming on the market, we can see where he got the inspiration. We understand [Josh]’s disappointment, but there were a lot of wins here, from the excellent build quality to the top-notch documentation. | 18 | 5 | [
{
"comment_id": "6206592",
"author": "Tracy",
"timestamp": "2019-12-31T15:35:03",
"content": "lost-cost? Very descriptive term especially if it’s a failed project!",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6206609",
"author": "Truth",
"... | 1,760,373,638.765928 | ||
https://hackaday.com/2019/12/31/reverse-engineer-pcbs-with-sprintlayout/ | Reverse Engineer PCBs With SprintLayout | Al Williams | [
"Software Hacks"
] | [
"pcb",
"reverse engineering",
"scan"
] | [Bwack] had some scanned pictures of an old Commodore card and wanted to recreate PC boards from it. It’s true that he could have just manually redrawn everything in a CAD package, but that’s tedious. Instead,
he used SprintLayout 6.0
which allows you to import pictures and use them as a guide for recreating a PCB layout.
You can see the entire process including straightening the original scans. There are tools that make it very easy to place new structures over the original scanned images.
One might think the process could be more automated, but it looks as though every piece needs to be touched at least once, but it is still easier than just trying to eyeball everything together.
Most of the video is sped up, which makes it look as though he’s really fast. Your speed will be less, but it is still fairly quick to go from a scan to a reasonable layout.
The software is not free, but you can do something somewhat similar in KiCAD. The trick is to get the image scaled perfectly and convert it to a component on a user layer. Then you can add the new component and enable the user layer to see the image as you work. There’s even
a repository of old boards recreated in KiCAD
.
There are probably
an infinite number of ways
to attack this. An older version of SprintLayout helped with the
Re-Amiga 1200
. | 20 | 12 | [
{
"comment_id": "6206580",
"author": "e",
"timestamp": "2019-12-31T14:03:05",
"content": "For those looking for FOSS options, gEDA PCB has been able to do this since at least 2007, iirchttp://www.delorie.com/pcb/bg-image.htmlplus pcb-rnd supports it as well, and can also import eeschema netlists and... | 1,760,373,638.828872 | ||
https://hackaday.com/2019/12/31/your-ts80-music-player/ | Your TS80 – Music Player | Jenny List | [
"Tool Hacks"
] | [
"firmware",
"soldering iron",
"ts100"
] | By now most readers will be familiar with the Miniware TS100 and TS80 soldering irons, compact and lightweight temperature controlled soldering tools that have set a new standard at the lower-priced end of the decent soldering iron market. We know they have an STM32 processor, a USB interface, and an OLED display, and that there have been a variety of alternative firmwares produced for them.
Take a close look at the TS80, and you’ll find the element connector is rather familiar. It’s a 3.5 mm jack plug, something we’re more used to as an audio connector. Surely audio from a soldering iron would be crazy? Not if you are [Joric], who has
created a music player firmware
for the little USB-C iron. It’s hardly a
tour de force
of musical entertainment and it won’t pull away the audiophiles from their reference DACs, but it does at least produce a recognisable
We Wish You A Merry Christmas
as you’ll see from the video below the break.
Since
the TS100 arrived
a couple of years ago we’ve seen a variety of inventive firmware for it. You may remember [Joric]’s previous triumph of a Tetris game for the iron, but our favourite is probably
the TS100 oscilloscope
.
Thanks [cahbtexhuk] for the tip. | 11 | 4 | [
{
"comment_id": "6206544",
"author": "Cees",
"timestamp": "2019-12-31T09:29:02",
"content": "those earphones are fried",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6206566",
"author": "Dave",
"timestamp": "2019-12-31T12:07:11",
"content": "I’m of... | 1,760,373,638.879552 | ||
https://hackaday.com/2019/12/30/36c3-build-your-own-quantum-computer-at-home/ | 36C3: Build Your Own Quantum Computer At Home | Sven Gregori | [
"cons",
"Science"
] | [
"36C3",
"diy",
"ion trap",
"quantum computer",
"quantum computing",
"quantum cryptography"
] | In any normal situation, if you’d read an article that about building your own quantum computer, a fully understandable and natural reaction would be to call it clickbaity poppycock. But an event like the Chaos Communication Congress is anything but a normal situation, and you never know who will show up and what background they will come from. A case in point: security veteran [Yann Allain]
who is in fact building his own quantum computer in his garage
.
Starting with an introduction to quantum computing itself, and what makes it so powerful also in the context of security, [Yann] continues to tell about his journey of building a quantum computer on his own. His goal was to build a stable computer he could “easily” create by himself in his garage, which will work at room temperature, using
trapped ion
technology. After a few iterations, he eventually created a prototype with KiCad that he cut into an empty ceramic chip carrier with a hobbyist CNC router, which will survive when placed in a vacuum chamber. While he is still working on a DIY laser system, he feels confident to be on the right track, and his estimate is that his prototype will achieve 10-15 qubits with a single ion trap, aiming to chain several ion traps later on.
As quantum computing is often depicted as cryptography’s doomsday device, it’s of course of concern that someone might just build one in their garage, but in order to improve future cryptographic systems, it also requires to fully understand — also on a practical level — quantum computing itself. Whether you want to replicate one yourself, at a rough cost of “below 15k Euro so far” is of course a different story, but who knows, maybe [Yann] might become the Josef Prusa of quantum computers one day. | 20 | 8 | [
{
"comment_id": "6206531",
"author": "JM",
"timestamp": "2019-12-31T07:23:13",
"content": "“As quantum computing is often depicted as cryptography’s doomsday device”Can anyone tell me if this is still true since:“Perfect secrecy cryptography via mixing of chaotic waves in irreversible time-varying s... | 1,760,373,638.933445 | ||
https://hackaday.com/2019/12/30/cat-diner-now-under-new-management/ | Cat Diner Now Under New Management | Kristina Panos | [
"Lifehacks",
"Microcontrollers"
] | [
"automatic cat feeder",
"NodeMCU",
"servo"
] | Most of these stories start with a cat standing on someone’s chest, begging for food at some obscene hour of the morning. But not this one. Chaz the cat is diabetic, and he needs to get his insulin with breakfast. The problem is that Chaz likes to eat overnight, which ruins his breakfast appetite and his chances at properly metabolizing the insulin. [Becky] tried putting the bowl away before bed, but let’s face it — it’s more fun to solve a problem once than to solve the same problem every night.
[Becky]’s solution was to design and print a bowl holder with a lid, and to cover the bowl when the cat diner is closed using a small servo and a NodeMCU.
It looks good, and it gets the job done with few components
. Chaz gets his insulin, [Becky] gets peace of mind, and everybody’s happy. This isn’t going to work for all cats, because security is pretty lax. But Chaz is a senior kitty and therefore disinterested in pawing at the lid to see what happens. Claw your way past the break to see [Becky]’s build/demo video featuring plenty of cat tax coverage.
We’ve seen a lot of cat feeding apparatus around here, but few that solve a specific problem like this one.
If it’s overengineering and cat metrics you want, come and get it
. | 12 | 7 | [
{
"comment_id": "6206552",
"author": "Hank R. Hill",
"timestamp": "2019-12-31T10:38:43",
"content": "My cat would destroy that contraption in less than one minute.Which, of course, doesn’t mean that said contraption isn’t a thumbsup-worthy build!",
"parent_id": null,
"depth": 1,
"replies... | 1,760,373,639.133399 | ||
https://hackaday.com/2019/12/30/36c3-sim-card-technology-from-a-to-z/ | 36C3: SIM Card Technology From A To Z | Sven Gregori | [
"Cellphone Hacks",
"cons"
] | [
"2g",
"36C3",
"3g",
"4g",
"5g",
"cellular network",
"eSIM",
"gsm",
"sim card",
"technology"
] | SIM cards are all around us, and with the continuing growth of the Internet of Things, spawning technologies like NB-IoT, this might as well be very literal soon. But what do we really know about them, their internal structure, and their communication protocols? And by extension, their security? To shine some light on these questions, open source and mobile device titan [LaForge] gave an
introductory talk about SIM card technologies
at the 36C3 in Leipzig, Germany.
Starting with a brief history lesson on the early days of cellular networks based on the German C-Netz, and the origin of the SIM card itself, [LaForge] goes through the main specification and technology parts of each following generation from 2G to 5G. Covering the physical basics, I/O interfaces, communication protocols, and the file system located on the SIM card, you’ll get the answer to “what on Earth is PIN2 for?” along the way.
Of course, a talk like this, on a CCC event, wouldn’t be complete without a deep and critical look at the security side as well. Considering how over-the-air updates on both software and — thanks to mostly running Java nowadays — feature side are more and more common, there certainly is something to look at. | 1 | 1 | [
{
"comment_id": "6206492",
"author": "Ostracus",
"timestamp": "2019-12-31T00:35:26",
"content": "Over an hour. Gonna keep someone busy. Big files too.",
"parent_id": null,
"depth": 1,
"replies": []
}
] | 1,760,373,639.169379 | ||
https://hackaday.com/2019/12/30/focus-stacking-for-tiny-subjects/ | Focus Stacking For Tiny Subjects | Lewin Day | [
"classic hacks"
] | [
"camera",
"focus stacking",
"macro",
"microscopy"
] | Focus stacking is a photographic technique in which multiple exposures are taken of a subject, with the focus distance set to different lengths. These images are then composited together to create a final image with a greater depth of field than is possible with a single exposure.
[Peter Lin] built a rig for accurate focus stacking with very small subjects.
The heart of the rig is a motion platform consisting of a tiny stepper motor fitted with a linear slide screw. This is connected to an Arduino or PIC with a basic stepper driver board. While the motor does not respond well to microstepping or other advanced techniques, simply driving it properly can give a resolution of 15 μm per step.
The motor/slide combination is not particularly powerful, and thus cannot readily be used to move the camera or optics. Instead, the rig is designed for photography of very small objects, in which the rail will move the subject itself.
It’s a tidy build that would serve well for anyone regularly doing macro focus stack photography. If you’ve been trying to better photograph your insect collection, this one is for you. It’s a valuable technique
and one that applies to microscopy too.
Video after the break.
https://www.youtube.com/watch?v=OzjuAQ87zjY | 25 | 11 | [
{
"comment_id": "6206448",
"author": "᷂",
"timestamp": "2019-12-30T21:17:29",
"content": "There are plenty of software packages available to help here as well. Some are open source and some are not. In addition, some are good and some are not so good and are slow and very old, not optimized software... | 1,760,373,639.235013 | ||
https://hackaday.com/2019/12/30/jeremy-cook-is-living-his-strandbeest-dream/ | Jeremy Cook Is Living His Strandbeest Dream | Tom Nardi | [
"cons",
"Robots Hacks"
] | [
"2019 Hackaday Superconference",
"ClearWalker",
"iterative design",
"robot walker",
"strandbeest"
] | The first thing Jeremy Cook thought when he saw a video of Theo Jansen’s Strandbeest walking across the beach was how incredible the machine looked. His second thought was that there was no way he’d ever be able to build something like that himself. It’s a feeling that most of us have had at one time or another, especially when starting down a path we’ve never been on before.
But those doubts didn’t keep him from researching how the Strandbeest worked, or stop him from taking the first tentative steps towards building his own version. It certainly didn’t happen overnight. It didn’t happen over a month or even a year, either.
ClearCrawler at the 2019 Hackaday Superconference
For those keeping score, his talk at the 2019 Hackaday Superconference,
“Strandbeests: From Impossible Build to Dominating My Garage”
is the culmination of over six years of experimentation and iteration.
His first builds could barely move, and when they did, it wasn’t for long. But the latest version, which he demonstrated live in front of a packed audience at the LA College of Music, trotted across the stage with an almost otherworldly smoothness. To say that he’s gotten good at building these machines would be something of an understatement.
Jeremy’s talk is primarily focused on his Strandbeest creations, but it’s also a fascinating look at how a person can gradually move from inspiration to mastery through incremental improvements. He could have stopped after the first, second, or even third failure. But instead he persisted to the point he’s an expert at something he once believed was out of his reach.
Learning to Crawl
There’s a well known Chinese proverb that, roughly translated, states “a journey of a thousand miles begins with a single step.” It’s something to keep in mind any time you take on a challenge, but it rings especially true for anyone looking to build a Strandbeest. Rather than trying to tackle the entire machine at once, Jeremy thought a reasonable enough approach to constructing a multi-legged walking robot was to first
build a single leg and understand how it operates
.
One of the early wooden designs.
With one leg built and working, the next step was of course to build more of them. When he had four assembled, it was time to design a base to mount them on, and then outfit it with electric motors to get things moving.
Unfortunately this first Strandbeest, made of wood and roughly the size of a golf cart, never worked very well. Jeremy attributes its failure to a number of issues which he would eventually learn to solve, such as imprecision in the linkages, excessive friction, and undersized motors. That first build may have failed as a walker, but it served as a fantastic learning experience.
For the second Strandbeest Jeremy switched over to cutting the parts out of MDF, but the contraption was still too heavy. This version was even less successful than the first, and it soon fell apart. It seemed clear at this point that the way forward was to scale the design down to a more manageable size.
The Next Generation
Once he shrunk the walker’s design down to tabletop scale,
Jeremy really started seeing some progress
. It still took a few iterations to get something that could move around without jamming up or rattling itself to pieces, but with parts that could be accurately cut on a CNC router and the addition of a new geared drive system, these smaller Strandbeests really started to come alive.
Smaller, gear-driven, walkers proved successful
Not only did they perform much better, but the eventual switch to clear acrylic gave them a very distinctive look. Around this time, Jeremy also started to add some anthropomorphic features, like articulated “heads” that housed cameras or LED “eyes”. These features not only gave his bots the ability to emote, but also marked a clear separation between his creations and that of Theo Jansen,
who’s designs were only getting larger and more alien
as time went on.
The
latest and greatest of these acrylic Strandbeests is the ClearCrawler
, which takes into account all the lessons Jeremy has learned over the years. Powered by an Arduino Nano and controllable via a custom handheld remote using nRF24L01 modules, this walker is easily expandable and provides an excellent platform for further research and exploration.
Staying Humble
Despite the leaps and bounds that Jeremy has made with his Strandbeests, he still remains in awe of the original wind-powered walkers that Theo Jansen unveiled all those years ago. If anything, he says he has more respect for those creations now than when he first saw them. Looking at it with no knowledge of how it works, you’ll of course be impressed. But once you understand the mechanisms involved, and just how hard it is to build and operate these creations, you realize what a monumental accomplishment it really was.
Which is perhaps the real lesson to be learned after watching Jeremy’s talk: there’s always more to learn and be impressed by. Even if you’ve been working on a particular project for years and now are at the point where you’re giving presentations on it at a hardware hacking conference, don’t be surprised if you still find yourself scratching your head from time to time. Rather than being discouraged, use the experience as inspiration to keep pushing forward and learning more. | 5 | 4 | [
{
"comment_id": "6206444",
"author": "Nathan",
"timestamp": "2019-12-30T20:58:34",
"content": "You were so close to “living his strandbeest-life.”",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comment_id": "6206498",
"author": "qwert",
"timestamp": "2019-12-31T01:1... | 1,760,373,639.282665 | ||
https://hackaday.com/2019/12/30/linux-fu-leaning-down-with-exec/ | Linux Fu: Leaning Down With Exec | Al Williams | [
"Hackaday Columns",
"Linux Hacks",
"Skills"
] | [
"bash",
"exec",
"linux",
"Linux Fu",
"shell scripting"
] | Shell scripting is handy and with a shell like bash it is very capable, too. However, shell scripting isn’t always very efficient. Think about it. If you run
grep
or
tr
or
sort
to do some operation in a shell script, you are spawning a whole new process. That takes time and resources. But there are some answers to reducing — but not eliminating — the problem.
Have you ever written a program like this (in any language, but I’ll use C):
int foo(void)
{
...
bar();
}
You hope the compiler doesn’t write assembly code like this:
_foo:
....
call _bar
ret
Most optimizers should pick up on the fact that you can convert a call like this to a jump and let the ret statement in _bar return to foo’s caller. However, shell scripts are not that smart. If you have a shell script called MungeData and it calls another program or shell script called PostProcess on its last line, then you will have at one time three processes in play: your original shell, the shell running MungeData, and either the PostProcess program or a shell running the script. Not to mention, the processes to do things inside post process. So what do you do?
Enter Exec
There are a few possible answers to this, but in the particular case where one shell script calls another program or script at the end, the answer is easy. Use exec:
#!/bin/bash
# Do stuff here
...
# Almost done
exec PostProcess
This tells the shell to reuse the current process for PostProcess. Nothing that appears after the exec will run because the current process is wiped out. When PostProcess completes, the original process that called our script will resume. This is pretty much the same as the call/ret to jump optimization in C.
Built Ins
If you look at the bash manual, some things are built in and some are not. Using built ins ought to be faster than spawning a new program. For example, consider a line like:
if [ $a == $b ]
Some shells use a program named “test” to handle the square brackets. This causes a new program to launch. Modern bash provides this as a built in to help speed script execution and make it more efficient. However, you can disable it if you want to benchmark the difference. In general, you can disable a built in using “enable -n XXX” where XXX is the built in you want to disable. Use no options to enable it. Just entering the command with no arguments at all will give you a list of built in commands or use the -p option, if you prefer.
However, there’s more to it than that. If you have some common operation that takes a lot of overhead, you can write the code in a language such as C and ask the shell to load it as a shared object and then treat it as a built in. The technique is a little involved, but it shows the versatility of the shell. You can find an example that adds a few built in commands to bash
in this article
. For example, the code posted makes things like
cat
and
tee
part of the shell, as well as creating new commands.
Exotic Solutions
We’ll admit, that last solution is a bit exotic. However, there are other things you can do. You might create a persistent server and communicate with it
using a named pipe
to avoid running new code. When disks were slow, you could experiment with keeping frequently used programs on a RAM disk. Today, caching ought to do that almost automatically, but perhaps not in every scenario.
Sometimes just cleaning up your code can help. Imagine this:
cat "$1" | grep "$target"
This spawns two processes, one for cat and one for grep. Why not just say:
grep "$target" "$1"
Of course, the ultimate is to simply not use a shell script. Almost any programming language will have a richer set of things it can do without launching an external program. A compiled or semi-compiled language is likely to be faster and even will help you optimize.
Shell scripts are useful to a point. It is fun, too, to see just how far you can stretch them. However, if you are really that worried about efficiency or speed, this might be the best answer of all. | 11 | 4 | [
{
"comment_id": "6206476",
"author": "tym0tym",
"timestamp": "2019-12-30T23:23:13",
"content": "Why not ‘grep “$target” “$1″‘? Because I like to see my data flow from left to right. This is why I use cat on the left and redirect stdout on the right.Also this is why in R I use magrittr library with i... | 1,760,373,639.406687 | ||
https://hackaday.com/2019/12/30/36c3-all-wireless-stacks-are-broken/ | 36C3: All Wireless Stacks Are Broken | Elliot Williams | [
"Android Hacks",
"cons",
"Security Hacks",
"Wireless Hacks"
] | [
"bluetooth",
"cellphone",
"security",
"wifi"
] | Your cellphone is the least secure computer that you own, and worse than that, it’s got a radio. [Jiska Classen] and her lab have been hacking on cellphones’ wireless systems for a while now, and in this talk
gives an overview of the wireless vulnerabilities and attack surfaces
that they bring along. While the talk provides some basic background on wireless (in)security, it also presents two new areas of research that she and her colleagues have been working on the last year.
One of the new hacks is based on the fact that a phone that wants to support both Bluetooth and WiFi needs to figure out a way to share the radio, because both protocols use the same 2.4 GHz band. And so it turns out that the Bluetooth hardware has to talk to the WiFi hardware, and it wouldn’t entirely surprise you that when [Jiska] gets into the Bluetooth stack, she’s able to DOS the WiFi. What this does to the operating system depends on the phone, but many of them just fall over and reboot.
Lately [Jiska] has been doing a lot of fuzzing on the cell phone stack enabled by some work by one of her students [Jan Ruge] work on emulation, codenamed “Frankenstein”. The coolest thing here is that the emulation runs in real time, and can be threaded into the operating system, enabling full-stack fuzzing. More complexity means more bugs, so we expect to see a lot more coming out of this line of research in the next year.
[Jiska] gives the presentation in a tinfoil hat, but that’s just a metaphor. In the end, when asked about how to properly secure your phone, she gives out the best advice ever: toss it in the blender. | 29 | 10 | [
{
"comment_id": "6206367",
"author": "Somun",
"timestamp": "2019-12-30T16:43:07",
"content": "“In the end, when asked about how to properly secure your phone, she gives out the best advice ever: toss it in the blender.”Well, I would advise to remove the lithium polymer battery first. Then you would ... | 1,760,373,639.348828 | ||
https://hackaday.com/2019/12/30/parallel-pis-for-production-programming-cutting-minutes-and-dollars-off-of-assembly/ | Parallel Pis For Production Programming; Cutting Minutes And Dollars Off Of Assembly | Bob Baddeley | [
"Engineering",
"Featured"
] | [
"assembly line",
"attiny",
"barcode scanner",
"openocd",
"pcb assembly",
"raspberry pi",
"Raspberry Pi Zero W",
"ws2812b"
] | Assembly lines for electronics products are complicated beasts, often composed of many custom tools and fixtures. Typically a microcontroller must be programmed with firmware, and the circuit board tested before assembly into the enclosure, followed by functional testing afterwards before putting it in a box. These test platforms can be very expensive, easily into the tens of thousands of dollars. Instead, this project uses a set of 12 Raspberry Pi Zero Ws in parallel to program, test, and configure up to 12 units at once before moving on to the next stage in assembly.
Fixing Fixture Bottlenecks
The company where I work,
Propeller Health
, develops IoT products that are assembled in a way similar to many other companies; there is a circuit board and a plastic enclosure. The bare PCBs go through SMT twice (components on the front and back), then they go through ICT (In-Circuit Test) where they are programmed and pogo pins on each of the test points verify all components on the circuit. They are also given a unique MAC address for Bluetooth based on a 2D barcode sticker placed on the board after SMT. After that they are assembled into the plastics and run through a functional test fixture before they are put into inventory mode and boxed. We have a product line of around a dozen different devices, and each uses a different PCB and enclosure.
Production runs need
test and programming fixtures, a topic i wrote about a few years ago
. To increase scale and reduce costs we started working more closely with our contract manufacturer to identify and fix the bottlenecks in the assembly line process, and we noticed that the ICT stage was taking 6 minutes for a panel of 6 boards. The ICT section itself was relatively fast, but the firmware programming and mac programming were taking a long time because the test platform was not capable of multiple simultaneous serial port connections.
This was a $30k fixture with 6 Segger programmers, 6 Keysight scanners, sitting on top of a $100k Teradyne platform, and it was our biggest bottleneck and greatest expense. Further, each device in our product line requires different fixturing. The combination of these expensive fixtures and slow cycle time was making our
COGS (Cost Of Goods Sold)
untenable.
On an assembly line, time is literally money, as every cycle time for every operator on the line is measured and added to the cost of the product. Reducing a cycle by even a second adds up quickly over a volume of thousands. Over 10k units, 2 second reduction is 6 hours of labor, at $15/operator hour is $.01/unit, and CMs, especially US based ones, are charging more than $15/hour. Having a 6 minute cycle time for 6 pieces was ripe for improvement.
Stage One – Arduino
The first stage was more a proof of concept. Could we pull some of the functionality off of the expensive ICT fixture onto a cheaper faster fixture so that we could scale in serial instead of buying another fixture to scale in parallel?
For this stage we implemented a feature in our firmware we call self-test, which is similar to a
JTAG boundary scan
. Rather than placing pogo pins on every net, we put a feature into the firmware to run a self-test on as many components as it could, and report the results over serial. This way we’d be able to connect only with the power and UART pins and get a complete and very fast readout of what exactly failed. Eight Arduinos connected via a USB hub to a tablet PC with a custom Python script and interface was the solution.
A single 40pin IDE connector was enough to have power, an RGB LED, RX, TX, and a single button that would kick off the cycle for all 8 at once. The Arduino would request a self-test from the DUT (Device Under Test), which would test its components and report back. Tests included verifying that sensors were reading values within an expected range, but also turning on the LED and buzzer and measuring the voltage drop to verify that outputs worked as well.
The microcontroller executes a series of tests on its own components and verifies they are within preset ranges, then reports success or failure.
This worked, and proved the concept of creating a box with most of the electronics paired with a simple customized fixture for the panel, but it wasn’t enough. Pulling out some of the circuit tests was insufficient to reduce time significantly. We needed to pull out more tasks.
Stage Two – Raspberry Pi
One of the more expensive parts of the ICT fixture was the Segger J-Link programmers. If we could pull out programming from ICT with something cheaper, we could reduce fixture costs significantly. Many chip manufacturers offer programming at the factory so that your microcontrollers come on a reel with your firmware pre-programmed. This is useful when you don’t trust your manufacturer or don’t want to have a special fixture for programming, but it does have an added cost, and there’s a lead time, and changing your firmware is more difficult, and you can’t use that part on any other product.
Programming in house had a lot of appeal for us, simplified our supply chain, and gave us more flexibility to change our firmware and shift inventory as needed. Enter the Raspberry Pi Zero W and
OpenOCD
. The Raspberry Pi is more than capable of running OpenOCD to program a microcontroller, and was surprisingly easy to configure and get running. It also had a serial port and GPIO for controlling WS2812B LEDs, and was small enough that it was easy to put a bunch in a box.
The connector expanded to a second 40pin IDE cable, and support for up to 12 parallel units, the size of our largest panels. Each Pi runs completely independently, without communicating with each other. The only thing they have in common (besides power supply) is that all 12 are connected to the same pushbutton on the front of the fixture. The button is used by the operator to start the programming cycle, but each Pi runs its process independently.
The prototype box contains all the components, wired together in a giant nest with Dupont cables that easily disconnected, in a custom laser-cut and glued acrylic enclosure for extra fragility.
Drawing on the Arduino experience further, the Raspberry Pi process would first program the unit, then verify it was programmed correctly by communicating over the UART, then execute the self-test on the device, which would test the accelerometer, microphone, IR sensors, LED, buzzer, etc, and report back the results and a PASS/FAIL status. We had accomplished our primary goal of removing a significant portion of the process time and cost from the ICT fixture, but we could go further.
Stage Three – Adding Features
A panel of 10 PCBs with unique MAC address stickers. The MAC address is scanned and programmed into the module.
With the addition of cameras to the fixture, we could read the MAC address on the sticker and use the serial port to program the MAC address into the unit. This allowed us to tie our process to the MAC address that was used to track the unit through the rest of the assembly line.
If you’re wondering why we didn’t pre-assign numbers and then have the operators put on the correct number, it comes down to reducing the chances for operator error. Giving the operator a sheet of stickers and telling them to put them on the units is way less error-prone than having them put specific stickers on specific units, and faster than printing out barcodes one at a time for individual units.
A fixture with 12 cameras for scanning barcodes. Notice the big green button in front of the fixture for starting a cycle.
Next we added the unique key stored on the unit for authenticated communication. The pi generates a 64 byte key, programs and verifies that key on the sensor, then encrypts the key and stores it in the log file. That key gets decrypted on our servers and allows us to communicate with our sensors.
In addition, we added thorough logging; a system log tracks the version numbers of the script, config file, and firmware file, and a separate file logs each cycle with diagnostic data about each stage of the process. These logs are stored on a thumb drive, but also uploaded regularly to a secure FTP so that we can import the logs (and the encrypted keys) immediately, as well as keep tabs on our CM and monitor when they are running our jobs and help them diagnose any problems.
We also made all of this run off a thumb drive. On boot the pi starts a Python script whose sole job is to wait for a thumb drive to be inserted, then run the script on that thumb drive. The thumb drive contains the main Python script, config file, firmware hex file, and logs. This way we have a single box that is completely agnostic to the assembly line, and then we have a dozen thumb drives that stay with the line for that particular device. We don’t need an interface to the pi because we can just plug the thumb drive into a computer to configure it however needed. Anything that makes the job easier for operators makes the assembly line run smoother, and saying “plug these into the back of the box” worked pretty well.
At this point we could program the microcontroller, then execute a self-test, then program the MAC address, and generate a unique key, and output to an LED the status of the process (green for success, yellow for in progress, and red for failure), and save the log to a file. This shaved MINUTES off the cycle time. Before, a panel of 12 was split in two, then each half went through the ICT fixture for 6 minutes, for a total cycle time of around 12 minutes for 12 devices. After the change, we had the full panel of 12 take under a minute, then split and spend under 2 minutes each at ICT. We went from 12 in 12 minutes to 12 in 5 minutes, with more control over the process and greater transparency.
Stage Four – Neptune is Alive
The assembled Neptune box contains 12 Raspberry Pi Zero W, 12 LEDs, 12 USB cables, and cost less than $500 total.
After our first box worked, our CM asked for more so they could service multiple assembly lines, plus have backups and one for test/development. The design was formalized, we found a new enclosure that could be modified easily, and designed a PCB. Total cost for all components is around $500, and the PCBs are easy enough to assemble by hand in a couple hours. We called the project Neptune and the boxes started coming together. Now we have plenty of Neptune boxes, and we have a spec for our fixture developer that allows them to have a very simple circuit they can replicate over and over. Fixtures are rugged beasts that require special knowledge and experience that we don’t have and don’t want to develop, so we outsource that part. The most recent fixture worked immediately with no changes, which is usually nearly impossible.
Stage Five – Changing Cameras
A MAC address sticker is placed on every unit after SMT, but this address must be programmed into the microcontroller itself. To do this, a barcode scanner is used. This is a production environment, and we are packing 12 scanners into a small space, and the scanners must accurately and reliably detect a 2D barcode about 1/2in^2, so not just any scanner will do.
Originally, on the suggestion of our CM, the fixtures were outfitted with Keyence scanners. After we discovered that these are $1400 each, we realized a huge potential for cost reduction. Each of our fixtures has 10-12 devices per panel, so replacing the Keyence scanners with $250 Zebra scanners was an immediate gain. The downside is that our Neptune PCB was designed for RS232 communication with the Keyence scanners using only 2 UART pins, and the Zebra scanners required 5V logic levels with hardware RTS/CTS pins as well. Fortunately we were able to build a cable with an inline circuit that contained an ATtiny84 for each of the cameras.
The adapter converts RS232 to 5V logic and triggers the Zebra camera.
With a small config file change, we can tell the system to use a slightly different communication protocol. The Pi sends a serial signal, which is stepped up to RS232 inside the Neptune box, then on the cable dongle it steps down to 5V, goes into the ATtiny, where it is parsed, and if the desired signal then it sends a pulse to the trigger pin of the Zebra scanner, which then scans the barcode and sends the result back to the dongle, where it is stepped up to RS232 and heads back to the unit. The dongle meant that we didn’t have to change anything about the box, and the fixture didn’t have any additional circuitry as well.
Results
The results of Neptune have saved the company a lot of money in fixtures and in unit cost, improved our scalability, given us greater transparency in our production, added features, and made development of new features easier. The Raspberry Pi was instrumental in this, as was OpenOCD. We learned a lot and developed some techniques that would likely be valuable to anyone else doing manufacturing of electronic devices. We’re still working out exactly how we can share this without compromising security or trade secrets, but this is our first step. | 36 | 13 | [
{
"comment_id": "6206345",
"author": "geocrasher",
"timestamp": "2019-12-30T15:21:35",
"content": "This is great! I really enjoyed reading it. There’s only one thing missing from this and it left me thinking I was missing something, but I re-read the article and couldn’t figure it out:What’s a CM?(T... | 1,760,373,639.502034 | ||
https://hackaday.com/2019/12/30/image-sensor-from-discrete-parts-delivers-glorious-1-kilopixel-images/ | Image Sensor From Discrete Parts Delivers Glorious 1-Kilopixel Images | Dan Maloney | [
"digital cameras hacks"
] | [
"ADG732",
"ALS-PT19",
"camera",
"image sensor",
"lens",
"multiplexer",
"mux",
"Obscura",
"photography",
"phototransistor"
] | Chances are pretty good that you have at least one digital image sensor somewhere close to you at this moment, likely within arm’s reach. The ubiquity of digital cameras is due to how cheap these sensors have become, and how easy they are to integrate into all sorts of devices. So why in the world would someone want to build
an image sensor from discrete parts that’s 12,000 times worse than the average smartphone camera?
Because, why not?
[Sean Hodgins] originally started this project as a digital pinhole camera, which is why it was called
“digiObscura.”
The idea was to build a 32×32 array of photosensors and focus light on it using only a pinhole, but that proved optically difficult as the small aperture greatly reduced the amount of light striking the array. The sensor, though, is where the interesting stuff is. [Sean] soldered 1,024 ALS-PT19 surface-mount phototransistors to the custom PCB along with two 32-bit analog multiplexers. The multiplexers are driven by a microcontroller to select each pixel in turn, one row and one column at a time. It takes a full five seconds to scan the array, so taking a picture hearkens back to the long exposures common in the early days of photography. And sure, it’s only a 1-kilopixel image, but it works.
[Sean] has had this project cooking for a while – in fact, the multiplexers he used for the camera came up as
a separate project
back in 2018. We’re glad to see that he got the rest built, even with the recycled lens he used. One wonders how
a 3D-printed lens
would work in front of that sensor. | 35 | 12 | [
{
"comment_id": "6206303",
"author": "biozz",
"timestamp": "2019-12-30T12:16:51",
"content": "I have always wanted to do this, even made up some designs. I’m glad someone followed through and made such a thing, I love it.",
"parent_id": null,
"depth": 1,
"replies": []
},
{
"comm... | 1,760,373,639.675689 | ||
https://hackaday.com/2019/12/30/vga-signal-in-a-browser-window-thanks-to-reverse-engineering/ | VGA Signal In A Browser Window, Thanks To Reverse Engineering | Donald Papp | [
"Linux Hacks",
"Video Hacks"
] | [
"driver",
"Epiphan",
"obsolete hardware",
"reverse engineering",
"usb",
"user space",
"vga",
"vga2usb",
"wireshark"
] | Epiphan VGA2USB LR VGA-to-USB devices
[Ben Cox] found some interesting USB devices on eBay. The Epiphan VGA2USB LR accepts VGA video on one end and presents it as a USB webcam-like video signal on the other. Never have to haul a VGA monitor out again? Sounds good to us! The devices are old and abandoned hardware, but they do claim Linux support, so one BUY button mash later and [Ben] was waiting patiently for them in the mail.
But when they did arrive, the devices didn’t enumerate as a USB UVC video device as expected. The vendor has a custom driver, support for which ended in Linux 4.9 — meaning none of [Ben]’s machines would run it. By now [Ben] was curious about how all this worked and began digging,
aiming to create a userspace driver for the device
. He was successful, and with his usual detail [Ben] explains not only the process he followed to troubleshoot the problem but also how these devices (and his driver) work. Skip to the end of the project page for the summary, but the whole thing is worth a read.
The resulting driver is not optimized, but will do about 7 fps. [Ben] even rigged up a small web server inside the driver to present a simple interface for the video in a pinch. It can even record its output to a video file, which is awfully handy. The code is available
on his GitHub repository
, so give it a look and maybe head to eBay for a bit of bargain-hunting of your own. | 25 | 9 | [
{
"comment_id": "6206275",
"author": "BrightBlueJim",
"timestamp": "2019-12-30T09:14:13",
"content": "Actually, I just bought a component video to USB capture stick for about $18 a little while back. I can’t guarantee it would work with VGA – there could be issues with getting the sync right, but V... | 1,760,373,639.90135 | ||
https://hackaday.com/2019/12/29/at-three-grand-a-tail-light-theres-an-opportunity-for-a-hacker/ | At Three Grand A Tail Light, There’s An Opportunity For A Hacker | Jenny List | [
"Transportation Hacks"
] | [
"Cadillac",
"Cadillac XLR",
"general motors",
"tail light"
] | It can be amusing sometimes, to read an incredulous reaction from outside our community to something that would be bread-and-butter in most hackerspaces. Take the sorry saga of the Cadillac XLR tail light,
as reported by Jalopnik
. This car was a more-expensive Corvette with a bit of lard around its midriff, and could appear a tempting pick for a bit of inexpensive luxury rubber-burning were it not for the revelation that a replacement second-hand tail light for one of these roadsters can set you back as much as three grand. The trusty auto on the drive outside where this is being written cost around a tenth that sum, so what on earth is up? Is it because a Caddy carries some cachet, or is something else at play?
It appears that the problem lies in the light’s design. It’s an LED unit, with surface mount parts and a set of fragile internal PCBs that are coated in something that makes reworking them a challenge. On top of that, the unit is bonded together, and instead of being a traditional on-off tail light it’s a microprocessor-controlled device that gets its orders digitally. This is all too much for XLR owners and for the Jalopnik hacks, who castigate General Motors for woefully inadequate design and bemoan the lack of alternatives to the crazy-expensive lights, but can’t offer an alternative.
Reading about the problem from a hardware hacker perspective they are right to censure the motor manufacturer for an appalling product, but is there really nothing that can be done? Making off-the-shelf microcontroller boards light up LEDs is an elementary introduction project for our community, and having the same boards talk to a car’s computer via CAN is something of a done deal. Add in LED strips and 3D printing to create a new backing for the tail light lens, and instead of something impossibly futuristic, you’re doing nothing that couldn’t be found in hackerspaces five years ago.
So what’s to be learned from the Cadillac XLR tail light? First of all, there’s scope for an enterprising hacker to make a killing on a repair kit for owners faced with a three grand bill. Then, there’s another opportunity for us to be acquainted with the reality that the rest of the world hasn’t quite caught up with repair culture as we might imagine. And finally there’s the hope that a badly designed automotive component might just be the hook by which the issue of designed-in obsolescence moves up the agenda in the public consciousness. After all, there will be other similar stories to come, and only bad publicity is likely to produce a change in behavior.
Of course, to get it really right you need
a car that’s hackable in the first place
. Or better still,
one designed by and for hackers
.
Thanks [str-alorman] for the tip.
Cadillac XLR header image:Rudolf Stricker [
CC BY-SA 3.0
]. | 65 | 16 | [
{
"comment_id": "6206253",
"author": "gronkasaurus-rex",
"timestamp": "2019-12-30T06:28:16",
"content": "It’s not microprocessor nor CAN/LIN bus controlled.The Jalopnik author failed hard at reading the wiring diagram.Read the article *and* the comments (there’s a few in there pointing out the autho... | 1,760,373,639.836381 | ||
https://hackaday.com/2019/12/29/the-smart-home-gains-an-extra-dimension/ | The Smart Home Gains An Extra Dimension | Ben James | [
"home hacks",
"Software Hacks"
] | [
"3d",
"blender",
"browser",
"gltf",
"home automation",
"hue",
"live",
"smart home",
"three.js",
"webapp"
] | With an ever-growing range of smart-home products available, all with their own hubs, protocols, and APIs, we see a lot of DIY projects (and commercial offerings too) which aim to provide a “single universal interface” to different devices and services. Usually, these projects allow you to control your home using a list of devices, or sometimes a 2D floor plan. [Wassim]’s project aims to take the first steps in providing a 3D interface, by creating an
interactive smart-home controller in the browser
.
Note: this isn’t just a rendered image of a 3D scene which is static; this is an interactive 3D model which can be orbited and inspected, showing information on lights, heaters, and windows. The project is well documented, and the code can be found on
GitHub
. The tech works by taking 3D models and animations made in Blender, exporting them using the .glTF format, then visualising them in the browser using three.js. This can then talk to Hue bulbs, power meters, or whatever other devices are required. The technical notes on this project may well be useful for others wanting to use the Blender to three.js/browser workflow, and include a number of interesting demos of isolated small key concepts for the project.
We notice that all the meshes created in Blender are very low-poly; is it possible to easily add subdivision surface modifiers or is it the vertex count deliberately kept low for performance reasons?
This isn’t our first unique home automation interface, we’ve previously written about
shAIdes, a pair of AI-enabled glasses that allow you to control your devices just by looking at them.
And if you want to roll your own home automation setup, we have plenty of resources. The Hack My House series contains valuable information on
using Raspberry Pis in this context
, we’ve got information on
picking the right sensors
, and even
enlisting old routers for the cause
. | 15 | 6 | [
{
"comment_id": "6206244",
"author": "Canoe",
"timestamp": "2019-12-30T05:23:52",
"content": "> vertex count deliberately kept low for performance reasons?Highly likely.I’m a former professional photographer, and I’ve seen Blender generated images that I couldn’t tell weren’t photographs. And some o... | 1,760,373,639.735997 | ||
https://hackaday.com/2019/12/29/hackaday-links-december-29-2019/ | Hackaday Links: December 29, 2019 | Dan Maloney | [
"Hackaday Columns",
"Hackaday links"
] | [
"ai",
"c64",
"Case mods",
"commodore",
"ERT",
"flex PCB",
"hackaday links",
"keycaps",
"kickstarter",
"machine learning",
"privacy",
"retrocomputing",
"RTL-SDR",
"rtlamr",
"security",
"spoofing",
"teardrop",
"YOLO"
] | The retrocomputing crowd will go to great lengths to recreate the computers of yesteryear, and no matter which species of computer is being restored, getting it just right is a badge of honor in the community. The case and keyboard obviously playing a big part in that look, so when a crowdfunding campaign to create new keycaps for the C64 was announced, Commodore fans jumped to fund it. Sadly, more than four years later, the promised keycaps haven’t been delivered. One disappointed backer, Jim Drew, decided he was sick of waiting, so he delved into the world of keycaps injection molding and
started his own competing campaign
. Jim details his adventures in his
Kickstarter
Indiegogo campaign, which makes for good reading even if you’re not into Commodore refurbishment. Here’s hoping Jim has better luck than the competition did.
Looking for anonymity in our increasingly surveilled world? You’re not alone, and in fact, we predict facial recognition spoofing products and methods will be a growth industry in the new decade. Aside from the obvious – and often illegal – approach of wearing a mask that blocks most of the features machine learning algorithms use to quantify your face, one now has another option, in the form of a
colorful pattern that makes you invisible to the YOLOv2 algorithm.
The pattern, which looks like a soft-focus crowd scene rendered in Mardi Gras colors, won’t make the algorithm think you’re someone else, but it will prevent you from being classified as a person. It won’t work with any other AI algorithm, but it’s still an interesting phenomenon.
We saw a great hack come this week about
using an RTL-SDR to track down a water leak
. Clayton’s water bill suddenly skyrocketed, and he wanted to track down the source. Luckily, his water meter uses the encoder receive-transmit (ERT) protocol on the 900 MHz ISM band to report his usage, so he threw an SDR dongle and
rtlamr
at the problem. After logging his data, massaging it a bit with some Python code, and graphing water consumption over time, he found that water was being used even when nobody was home. That helped him find the culprit – leaky flap valves in the toilets resulting in a slow drip that ran up the bill. There were probably other ways to attack the problem, but we like this approach just fine.
Are your flex PCBs making you cry? Friend of Hackaday Drew Fustini sent us
a tip on teardrop pads
to reduce the mechanical stress on traces when the board flexes. The trouble is that KiCad can’t natively create teardrop pads. Thankfully an action plugin makes teardrops a snap. Drew goes into a bit of detail on how the plugin works and shows the results of some test PCBs he made with them. It’s a nice trick to keep in mind for your flexible design work. | 25 | 9 | [
{
"comment_id": "6206213",
"author": "ERIC S CHAPIN",
"timestamp": "2019-12-30T00:45:30",
"content": "Nice job on teardrop design, I’d like to see one for Eagle CAD as well.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6206239",
"author": "tekkiene... | 1,760,373,639.964666 | ||
https://hackaday.com/2019/12/29/36c3-open-source-is-insufficient-to-solve-trust-problems-in-hardware/ | 36C3: Open Source Is Insufficient To Solve Trust Problems In Hardware | Sven Gregori | [
"cons",
"Security Hacks"
] | [
"36C3",
"fpga",
"hardware security",
"open source",
"open source hardware",
"trust"
] | With open source software, we’ve grown accustomed to a certain level of trust that whatever we are running on our computers is what we expect it to actually be. Thanks to hashing and public key signatures in various parts in the development and deployment cycle, it’s hard for a third party to modify source code or executables without us being easily able to spot it, even if it travels through untrustworthy channels.
Unfortunately, when it comes to open source hardware, the number of steps and parties involved that are out of our control until we have a final product — production, logistics, distribution, even the customer — makes it substantially more difficult to achieve the same peace of mind. To make things worse, to actually validate the hardware on chip level, you’d ultimately have to destroy it.
On
his talk this year at the 36C3
, [bunnie] showed a detailed insight of several attack vectors we could face during manufacturing. Skipping the obvious ones like adding or substituting components, he’s focusing on highly ambitious and hard to detect modifications inside an IC’s package with wirebonded or through-silicon via (TSV) implants, down to modifying the netlist or mask of the integrated circuit itself. And these aren’t any theoretical or “what if” scenarios, but actual possible options — of course, some of them come with a certain price tag, but in the end, with the right motivation, money is only a detail.
Sure, none of this is particularly feasible or even much of interest at all for a blinking LED project, but considering how more and more open source hardware projects emerge to replace fully proprietary components, especially with a major focus on privacy, a lack of trust in the hardware involved along the way is surely worrying to say the least. At this point, there is no perfect solution in sight, but FPGAs might just be the next best thing, and the next part of the talk is presenting the
Betrusted
prototype that [bunnie] is working on together with [xobs] and [Tom Marble]. That alone makes the talk worth watching, in our view. | 29 | 9 | [
{
"comment_id": "6206191",
"author": "Ostracus",
"timestamp": "2019-12-29T22:27:50",
"content": "“At this point, there is no perfect solution in sight, but FPGAs might just be the next best thing, and the next part of the talk is presenting the Betrusted prototype that [bunnie] is working on togethe... | 1,760,373,640.201655 | ||
https://hackaday.com/2019/12/29/turning-sounds-from-a-flute-into-sheet-music/ | Turning Sounds From A Flute Into Sheet Music | Sharon Lin | [
"Microcontrollers",
"Musical Hacks"
] | [
"Cornell University",
"fft",
"filters",
"flute",
"music",
"signals processing"
] | Composing music can be quite difficult – after all, you have to keep in mind all of the elements of musical theory, from time signature and key signature to the correct length for all of the notes. A team of students from Cornell University’s Designing with Microcontrollers class developed a solution for this problem by
transcribing sounds from a flute into sheet music
.
The project doesn’t simply detect the notes played – it is able to convert the raw audio into a standardized music score complete with accurate note timings and beats per minute. Before transcribing the music, some audio processing was necessary. The team chose to use a Sallen-Key filter to amplify the raw audio input due to its complex conjugate poles. They then used a fast Fourier Transform (FFT) to determine the frequency for the input note, converting the signal from the time domain to the frequency domain.
The algorithm samples the data to generate an input signal, using the ADC on the microcontroller to receive input from the microphone. It takes the real and imaginary components of the sampled signals and outputs a pair of real and imaginary amplitude components corresponding to the sampled frequency, evenly spaced from 0 to the Nyquist rate (half the sampling rate). The spacing of these bins and the bin with the largest amplitude are used to convert the signal back to a real frequency and a MIDI note.
The system uses a PIC32 for the logic. The circuitry for the microphone amplification uses a non-inverting op-amp with a gain of 50 to increase the microphone output signal amplitude from 15 mV to 750 mV to use by the microcontroller’s ADC. The signal is then sent to the anti-aliasing Sallen-Key filter, with a pole at 2.5 kHz and a Q of 1. The frequency was chosen since the FFT samples at 8 kHz and the frequency corresponds to a note out of the range of a flute. As for the filters, only the low pass filter was implemented in hardware. While a bandpass filter could have been implemented in hardware, the team decided on a cleaner software approach.
The project is well-documented on the team’s
project page
, and it’s certainly worth checking out for more detailed discussions on the keypad controls and the software side of the audio processing. If you want to learn more about the FFT, check out this
2016 Hackaday Prize entry for an FFT spectrum analyezer
. | 12 | 7 | [
{
"comment_id": "6206159",
"author": "Luke",
"timestamp": "2019-12-29T19:10:59",
"content": ">” only the low pass filter was implemented in hardware”The first amplification stage has a high pass filter built-in.https://www.electronics-notes.com/images/op-amp-high-pass-single-pole-filters-01.svg",
... | 1,760,373,640.015397 | ||
https://hackaday.com/2019/12/29/36c3-phyphox-using-smartphone-sensors-for-physics-experiments/ | 36C3: Phyphox – Using Smartphone Sensors For Physics Experiments | Sven Gregori | [
"cons",
"Phone Hacks"
] | [
"36C3",
"accelerometer",
"barometric pressure",
"gyroscope",
"magnetometer",
"mobile lab",
"mobile phone",
"physics"
] | It’s no secret that the average smart phone today packs an abundance of gadgets fitting in your pocket, which could have easily filled a car trunk a few decades ago. We like to think about video cameras, music playing equipment, and maybe even telephones here, but let’s not ignore the amount of measurement equipment we also carry around in form of tiny sensors nowadays. How to use those sensors for educational purposes to teach physics is
presented in [Sebastian Staacks]’ talk at 36C3
about the
phyphox mobile lab
app.
While accessing a mobile device’s sensor data is usually quite straightforwardly done through some API calls, the phyphox app is not only a shortcut to nicely graph all the available sensor data on the screen, it also exports the data for additional visualization and processing later on. An accompanying
experiment editor
allows to define custom experiments from data capture to analysis that are stored in an XML-based file format and possible to share through QR codes.
Aside from demonstrating the app itself, if you ever wondered how sensors like the accelerometer, magnetometer, or barometric pressure sensor inside your phone actually work, and which one of them you can use to detect toilet flushing on an airplane and measure elevator velocity, and how to verify your HDD spins correctly, you will enjoy the talk. If you just want a good base for playing around with sensor data yourself, it’s all open source and available on GitHub for both
Android
and
iOS
. | 7 | 3 | [
{
"comment_id": "6206150",
"author": "arcol",
"timestamp": "2019-12-29T18:07:29",
"content": "I have a phone with hall effect(?) sensor, so when I open or close my flip case (or placing a small magnet on the upper left corner) makes the device sleep or wake up(nokia 8.0).But I can not find on any pr... | 1,760,373,640.245711 | ||
https://hackaday.com/2019/12/29/analog-meter-clock-uses-parts-from-a-simpler-time/ | Analog Meter Clock Uses Parts From A Simpler Time | Lewin Day | [
"clock hacks"
] | [
"clock",
"dial clock",
"microchip",
"microcontroller",
"pic"
] | Clocks with hands that turn are all well and good for the common folk, but hacker types prefer something different. [Sjm4306] is one such person,
and developed this analog dial clock with parts we’d almost consider retro by modern standards.
The microcontroller at the heart of the build is a PIC16F886. An 8-bit micro from the Microchip brand, it features no Arduino bootloader or USB interface, being flashed via a dedicated programmer. This is combined with a DS1302 real-time clock to keep accurate time, and a MCP4922 DAC which is responsible for generating the output to drive the dials. The dials themselves are sourced from eBay, being simple voltmeters. They’re given a new backing to display hours and minutes instead of volts, and backlit with LEDs for style.
In this day and age, we’re more used to seeing high-end micros used with integrated DACs and USB programming, but it’s nice to see the parts of yesteryear being used, too.
It’s not the first clock we’ve seen from [sjm4306], either
. Video after the break. | 16 | 6 | [
{
"comment_id": "6206125",
"author": "Alex Rossie",
"timestamp": "2019-12-29T14:49:31",
"content": "The 16F886 is where I took refuge when the F84 begun to become cumbersome to source.",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6206643",
"author"... | 1,760,373,640.293585 | ||
https://hackaday.com/2019/12/29/fet-based-motor-driver-is-better-than-l298n/ | FET Based Motor Driver Is Better Than L298N | Al Williams | [
"Robots Hacks"
] | [
"h-bridge",
"L298N",
"motor controller",
"robot",
"tb6612",
"tb6612fng"
] | If you want to build a small robot with a motor, you are likely to reach for an L298N to interface your microcontroller to the motor, probably in an H-bridge configuration. [Dronebot] has used L298N chips like this many times. In the video below, he uses a TB6612FNG instead, taking advantage of the device’s use of MOSFETs. The TB6612 may be a little more expensive, but it’s clearly worth it.
You can get breakout boards for the tiny chips. [DroneBot] looks at several ready-to-go breakout boards. They are not drop-in compatible, though. For example, the L298N can operate motors from 4.5 to 46V while the TB6612 can go from 2.5 to 13.5V on the motor voltage. The L298N also handles more current. However, because of its relatively low efficiency, it needs a heat sink. The TB6612 boasts up to 95% efficiency and also has a low current standby mode. Of course, the TB6612 drops much less voltage which is great if you are using low voltage motor.
Assuming the new device is suitable for your hardware, the software isn’t really very different from L298N programs. If you know how to use the L298N, you can probably just snag a break out board, download the library, and be off to the races — no pun intended.
If you want more
basics on the h-bridge
, we’ve covered it many times. Of course, you can always use
relays
if you want real old school. | 20 | 10 | [
{
"comment_id": "6206097",
"author": "dendad",
"timestamp": "2019-12-29T09:51:40",
"content": "This is way better that the “Old Standard” L298N chips!!Have you looked at the A4950?https://www.allegromicro.com/~/media/Files/Datasheets/A4950-Datasheet.ashxI’ve used these in a BBB driven design.A singl... | 1,760,373,640.350908 | ||
https://hackaday.com/2019/12/28/building-a-spinning-moire-effect-lamp/ | Building A Spinning Moiré Effect Lamp | Lewin Day | [
"Misc Hacks"
] | [
"fan",
"moire",
"moire pattern",
"spin"
] | A concise, comical explanation of Moiré patterns, via
XKCD
.
Moiré patterns are interference patterns created when grids of different size or alignment are placed over each other. You’ve probably seen these when photographing a TV screen or looking through a pair of windows screens at the same time. [ChrysN] put the
effect to work with this spinning Moiré lamp build
.
It’s a build that can be achieved with scrap-bin components. An LED-encrusted PC cooling fan is used as the base of the lamp, fitted with Sugru bumpers to hold a cheap glass vase. A line pattern is then printed on to paper, rolled into a cylinder, and slid on to the fan to spin with the blades, inside the vase. Another line pattern is then printed on to a transparency (a printable transparent sheet for those who don’t remember overhead projectors) and slid around the outside of the vase. When powered up, the LEDs glow, and the fan spins, creating a hypnotizing moving moiré pattern.
It’s a simple but visually captivating build,
and one that should keep you up at night thanks to the blue LEDs
. Moiré patterns can do so much more though –
they’re even put to work guiding ships.
Video after the break. | 7 | 4 | [
{
"comment_id": "6206086",
"author": "Digital Corpus",
"timestamp": "2019-12-29T06:26:27",
"content": "The whole write up here with the xkcd quote made me smile. +3000 Internet Points",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6206104",
"author":... | 1,760,373,640.398845 | ||
https://hackaday.com/2019/12/28/subterranean-uses-for-lidar-cave-surveys/ | Subterranean Uses For LIDAR: Cave Surveys | Sharon Lin | [
"Laser Hacks",
"Microcontrollers"
] | [
"caves",
"gimbal",
"lidar",
"survey"
] | LIDAR has gained much popularity as a means for self-driving cars to survey the space around them. At their most basic, LIDAR is a surveying method that uses lasers to paints the space around the sensors and assembles the distances measured from reflected light into a digital three-dimensional representation. That’s something that has quite a number of other applications, from surveying ancient ruins and rainforests from a bird’s eye view to developing 3D models of indoor spaces.
One fascinating use of LIDAR technology is to map out the routes inside caves, subterranean spaces that are seldom accessed by humans apart from those with specialized equipment and knowledge of how to safely traverse the underground terrain. [caver.adam] has been
working on his Open LIDAR project for a few years
using an SF30-B High Speed Rangefinder and laser device for a dual-system atop a gimbal with stepper motors for cave scanning.
Originally an entry in the 2016 Hackaday Prize, [Adam] has continued to work on the project. The result shown in the video below is a cheaper 3D LIDAR setup that works by rotating the laser distance module on 2 axes with a sensor centered at the center of rotation. It works for volumetric calculations, detects change over time, and identifies various water patterns and rocks on a surface map. Compared to notebooks, tape measures, and compasses, it’s certainly a step up in cave surveying technology.
Check out some other past underground surveying projects, such as
Iowa City’s beer caves scanning projects
and National Geographic’s 2014
expedition of the Titan Chamber
in southern Guizhou Province in China. | 11 | 6 | [
{
"comment_id": "6206080",
"author": "Hirudinea",
"timestamp": "2019-12-29T03:53:31",
"content": "They did this in that horrible, horrible Prometheus movie.https://www.youtube.com/watch?v=3jeUTcNucYY",
"parent_id": null,
"depth": 1,
"replies": [
{
"comment_id": "6206273",
... | 1,760,373,640.517346 | ||
https://hackaday.com/2019/12/28/led-flame-illuminates-the-beauty-of-noise/ | LED Flame Illuminates The Beauty Of Noise | Kristina Panos | [
"Arduino Hacks"
] | [
"LED flame",
"Neopixels",
"Perlin noise",
"RGB LEDs",
"trinket pro"
] | Have you ever wrapped up a nice blinky project only to be disappointed by the predictability of the light or the color patterns? When it came to
lighting this LED candle
, so was [fungus amungus]. But there’s a better way, and it involves noise.
Perlin noise was created in the early 80s by Ken Perlin while he was working on the movie
Tron
. Frustrated by the current state of computer graphics and too limited on space to use images, he devised an algorithm for generating natural-looking textures. Basically, you generate a bunch of numbers between 0 and 1, then assign values to those numbers, such as a range of greyscale values from black (0) to white (1), or the values from the color wheel. The result is much prettier than random numbers because the neighboring values for any given number aren’t radically different. You get nice randomness with hardly any overhead.
[fungus amungus] is using the FastLED’s noise function to generate the numbers, but there’s a whole lot more going on here. As he explains in the excellent video after the break, if you want to animate these values, you just add another dimension of them. Although [fungus amungus] is using a Trinket Pro and a NeoPixel ring, we think a simplified version could be done with a Circuit Playground Express using the built-in LEDs.
If you want to do it the hard way,
start by making your own NeoPixel ring
. | 9 | 4 | [
{
"comment_id": "6206067",
"author": "CMH62",
"timestamp": "2019-12-29T02:46:33",
"content": "Oh my goodness … in the 70’s, my Dad used to say with a smile and laugh: “There’s a fungus among us”! Great Hackaday user name!!!😆",
"parent_id": null,
"depth": 1,
"replies": [
{
... | 1,760,373,640.583027 |
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