In 2021-22 I made these light up skates for dancing at roller discos. The code and 3D printing files are shared on GitHub here: https://github.com/DrewBatchelor/Drews-Skates
Electronics
The heart of the project is an Adafruit Feather Bluefruit Sense. Wow! This microcontroller is a beast, with Bluetooth phone control, battery charging and ALL the sensors. So much functionality, packed into the tiny Feather format. With Adafruit A++ quality for design, production and exceptional documentation.
The rest of the parts are:
- 2 LED strips, with 34 LEDs on each skate (WS2812B/Neopixels)
- A 3.7v Lipo Battery.
- An on/off switch, I thought that I could uses the board enable pin, but that didn’t unpower the LEDs, so I added an on/off switch to the battery wire.
- A couple of plugs and sockets and some wires. The total cost was around £60.
The circuit is minimal, and hard soldered to the board to save space.
Circuit Python Code
The skates are based on an amazing Light Up Ukulele tutorial by Erin St Blaine, with the audio input replaced by a Bluetooth phone app. The original Ukulele Code is on Github here.
I used this project to test drive Circuit Python, and see if it was a viable alternative to replace Arduino in my teaching of physical computing. (Quick answer: Yes – Circuit Python is great).
Enclosure
There were about 6 iterations of the enclosure. I shaved the tolerance down to make the box as small as possible. I could have saved several iterations and many hours work by making it a bit larger, but this time, I’m glad I over-optimised it, it helped me to refresh my professional Designer, Engineer and Solidworks skills.
The lump on the top is to clear the battery socket on the Feather, it would be easy to remove this socket and solder the battery directly on the Feather, but I wanted to be able to replace the board or the battery if needed in future.
The blue button covers on the top use the flex of the 3D print, and allow the light to shine through.
Product Architecture
I had a plan to have each skate have a separate microcontroller and battery, then have them talk to each other over Bluetooth. I realised it would be easier to put the controller in my pocket and run wires down my legs with a bonus that there is a control button in my pocket. This works really well, I don’t notice them when I am wearing them, although feeding wires down my trouser legs is a bit funny.
Mounting the LEDs on the Skates
The “Least-Worst” mounting was a couple of cable ties and a couple of pieces of hockey tape to fix the the LEDs to the skates, this worked remarkably well for a year. In September 2022, ready for Skatelove Barcelona, I designed and made 2 Orange 3D printed parts – waterproof silicone tube with diffuser to mount onto Powerdyne Arius Plates. I also upgraded the wires and added 3.5mm audio jacks for connections.
This has worked perfectly since I first made it… Which is weird and slightly surprising – sometimes it almost feels like I know what I’m doing.
What Next?
For the moment these are done, but there’s always room for some upgrades for the next iteration:
- Consider a bigger battery – I’ve got 3-4 hours run time, it would be good to have a bit more.
- Battery power indicator.
- Design and code some more custom light patterns.
- Add a ring to hang it onto a belt loop.
- Use some more of the sensors on the board.
- Learn how to create a bespoke Android App.