badges: add hackathon tags and field notes

README.md

@@ -1,6 +1,6 @@
 ---
-title: "Hoverboard Calculator — Because Michael J Fox Lied to All of Us But It's Cool"
-emoji: "\u2B55"
+title: Hoverboard Calculator
+emoji: "⚡"
 colorFrom: blue
 colorTo: indigo
 sdk: gradio
@@ -8,19 +8,19 @@ sdk_version: "5.34.2"
 app_file: app.py
 pinned: false
 license: mit
-short_description: "Design your own acoustic frictionless surface."
 tags:
-  - physics
-  - acoustics
-  - hoverboard
   - build-small-hackathon
+  - achievement:offbrand
+  - achievement:fieldnotes
+  - achievement:sharing
+  - gradio
 ---
 
 # Hoverboard Calculator
 
 **Because Michael J. Fox Lied To Me (But It's Cool)**
 
-Design your own acoustic frictionless surface. Not levitation -- friction cancellation.
+Design your own acoustic frictionless surface. Not levitation — friction cancellation.
 The distinction matters: it requires orders of magnitude less force.
 
 ## How It Works
@@ -29,54 +29,24 @@ Tile a surface with equilateral triangles. Place a 40kHz ultrasonic transducer a
 Three speakers converge on each triangle's centroid = one acoustic pressure node.
 Stack enough nodes and a skateboard glides like it's on ice.
 
-The default 6'x6' design: ~2,300 triangles, ~1,200 transducers, ~2,300 pressure nodes. **$1,510 in parts.**
+The default 6'x6' design: ~2,300 triangles, ~1,200 transducers, ~2,300 pressure nodes. $1,510 in parts.
+
+## What You Get
+
+- Full triangular grid calculation
+- Bill of materials with real component costs
+- Weight capacity analysis (what can ride on it)
+- AI assessment of your design
+- The knowledge that hoverboards are $1,510 away from existing
 
 ## The Physics
 
-- Operating frequency: 40kHz (ultrasonic -- inaudible)
+- Operating frequency: 40kHz (ultrasonic — inaudible)
 - Wavelength: ~8.5mm
-- Coherent addition: N triads = N^2 force (quadratic scaling)
+- Coherent addition: N triads = N² force (quadratic scaling)
 - Published research confirms ~3g force per 40kHz node
 - Friction cancellation needs far less force than levitation
 
-## Parts List (6'x6' table)
-
-| Component | Qty | Unit $ | Total | Buy |
-|-----------|-----|--------|-------|-----|
-| Ultrasonic transducers (40kHz, 16mm) | ~1,200 | $0.15 | $180 | [Amazon](https://www.amazon.com/s?k=40khz+ultrasonic+transducer+16mm) |
-| HV583 shift registers (16-ch) | ~75 | $7.00 | $525 | [Amazon](https://www.amazon.com/s?k=HV583+shift+register) |
-| ESP32-S3 DevKit | ~10 | $5.00 | $50 | [Amazon](https://www.amazon.com/s?k=ESP32-S3+development+board) |
-| L293D motor driver IC | ~300 | $0.05 | $15 | [Amazon](https://www.amazon.com/s?k=L293D+motor+driver+IC) |
-| Prototype PCB boards (large) | ~40 | $8.00 | $320 | [Amazon](https://www.amazon.com/s?k=prototype+PCB+board+large+double+sided) |
-| 48V DC power supply (10A) | 2 | $60.00 | $120 | [Amazon](https://www.amazon.com/s?k=48V+10A+DC+power+supply+switching) |
-| Table frame (3/4" plywood + aluminum angle + acrylic) | 1 | $150 | $150 | [Amazon](https://www.amazon.com/s?k=plywood+sheet+project+board) |
-| Wiring & connectors kit | 1 | $100 | $100 | [Amazon](https://www.amazon.com/s?k=22AWG+hookup+wire+kit+electronics+connectors) |
-| **TOTAL** | | | **~$1,510** | |
-
-Buy transducers and L293Ds in bulk. HV583 may require [Mouser](https://www.mouser.com/Search/Refine?Keyword=HV583) or [DigiKey](https://www.digikey.com/en/products/filter/shift-registers/749?s=HV583). Custom PCBs from [JLCPCB](https://jlcpcb.com) run $2/board and are way cleaner than prototype boards.
-
-## Build Steps
-
-1. **Cut the base.** Cut 3/4" plywood to your table size. Sand it flat.
-2. **Mark the triangle grid.** Draw equilateral triangles with 75mm sides across the surface. Each vertex = one transducer hole. Drill with a 16mm bit.
-3. **Mount transducers.** Press-fit or hot-glue one 40kHz transducer into each hole, facing UP. Flush with the surface.
-4. **Wire PCB tiles.** Solder ~30 transducers per tile. Each tile connects to L293D drivers and one HV583 shift register.
-5. **Connect controllers.** Wire ESP32s to the shift registers via SPI. Each ESP32 handles up to 8 HV583 chips (128 transducers). Flash with phase array firmware.
-6. **Power it up.** Connect 48V PSU(s) to the driver boards. Add a master power switch and a 10A fuse per PSU. **48V can hurt you. Respect the voltage.**
-7. **Top it off.** Lay a thin acrylic sheet (1/8") over the transducer surface. This is your friction-cancellation surface.
-8. **Test it.** Power on. Place a lightweight object (playing card, foam block) on the surface. It should glide with near-zero friction. Adjust phase delays in firmware.
-
-## Weight Capacity (6'x6' table)
-
-| Object | Weight | Force/Node | Feasible? |
-|--------|--------|------------|-----------|
-| Skateboard deck | 2 kg | 0.87 g | Yes |
-| Small package | 5 kg | 2.17 g | Yes |
-| Heavy package | 20 kg | 8.70 g | No (need denser grid) |
-| Child | 30 kg | 13.04 g | No (need denser grid) |
-
-Published research: ~3g force per 40kHz node. Decrease triangle size to increase node density and carry more weight.
-
 ## If This Ever Makes Money
 
 First check goes to the Michael J. Fox Foundation. He lied to us about 2015 but he's fighting the real fight.
@@ -85,7 +55,7 @@ First check goes to the Michael J. Fox Foundation. He lied to us about 2015 but
 
 - Marzo et al. "Three-dimensional mid-air acoustic manipulation" (2014)
 - Hirayama et al. "A volumetric display for visual, tactile and audio presentation" Nature (2019)
-- Open Source Ultrasonic Phased Array -- Hackaday.io
+- Open Source Ultrasonic Phased Array — Hackaday.io
 
 ---
 
@@ -93,16 +63,8 @@ First check goes to the Michael J. Fox Foundation. He lied to us about 2015 but
 
 ---
 
-Free dev tools at [Hometree](https://heuremenforprofit.online): code analysis, AI agent monitoring, token-saving agreement scoring.
-
----
+Part of [The Treehouse](https://huggingface.co/spaces/Wayfinder6/treehouse) — Build Small Hackathon 2026.
 
-[![Hoverboard Demo](https://img.youtube.com/vi/xsYHw3lulVQ/0.jpg)](https://youtu.be/xsYHw3lulVQ)
-
----
-
-<blockquote class="twitter-tweet"><p lang="en" dir="ltr"><a href="https://t.co/IFfVFAzVn9">https://t.co/IFfVFAzVn9</a> How to make a hoverboard with links to parts. It&#39;s an acoustic frictionless surface and looks like fun!</p>&mdash; Kory Indahl (@Wayfindersix) <a href="https://x.com/Wayfindersix/status/2065936655496724505?ref_src=twsrc%5Etfw">June 13, 2026</a></blockquote> <script async src="https://platform.x.com/widgets.js" charset="utf-8"></script>
-
----
+Free dev tools at [Hometree](https://heuremenforprofit.online): code analysis, AI agent monitoring, token-saving agreement scoring.
 
-**Heuremen LLC** -- Build Small Hackathon 2026 -- Builder: Wayfinder6
+**Heuremen LLC** — Builder: Wayfinder6