Augen Ohren Katze / Kitty Eye-Ear Motorcycle Helmet

Recently when I went shopping for protective gear, I stumbled over this helmet on aliexpress and thought it would be funny to give the kitty ears a more practical purpose for safety and aesthetics.

Following the adventures outlayed in Lights, Fairies and first Adventures in Electronics i thought it would be an interesting idea to have adressable LEDs in the ears, in the form of emoji-eyes that can not only display fluent idle animations, revealing the wearer’s otherwise hidden emotions but also sync up with the turnlights and possibly brake signal to display vital status and intent information to following and encountering traffic.

A good 2-3 weeks following the order, a delivery person rang on my doorbell and it was time to unwrap this modern piece of throwaway-culture art. Small decorative pieces had already broken off and needed to be glued back on. Who knows, maybe the helmet just done it’s job and gave way for being thrown onto the porch, protecting the styrofoam flakes at the insides…

The choice fell for NeoPixels due to their easily chainable and individually adressable nature, giving us 8 bit color space for each channel (rgb, brightness). We went for the offbrand ones and didn’t regret it. More on that later…

Powering this thing requires some sort of power source and if am already gonna strap a DIY powerbank onto my head, i might aswell be able to charge my phone from it, so I went with a powerbank PCB module that supports QuickCharge and Bi-Di PD not to be confused with BPD.
Safety note: Lithium pouch cells might cause you severe burns and pain if you fail to follow basic security measures, they might also just spontaneously go off… So think twice before putting this on your head. Maybe you can find a grill mat to cut in form as a barrier between you and molten lithium (glassfiber dust is arguably more vile tho)…

For those playing along at home, the tools we used were:

Soldering equipment including flux and pegs to hold wires in place while soldering
A set of small deburring files
A Philips Head (PH) screwdriver
Guitar pick or other thin plastic object for unclipping the decorative screw covers
Hot glue gun
Tweezers
Velcro, Double Sided Tape and Fishing wire or similar stuff for attaching and sticking things to the inside

The choice fell for this set of components:

A bunch a’ wires (LED wiring is sold as big spools, make your life easier and get copper wires [lower resistance, better signal integrity etc])
Pre-Crimped Micro JST PH 2.0mm 3PIN connectors (AZN link)
WS2812B 5V IC 5050 RGB LEDs (NeoPixel offbrands, AZN link)
NeoPixel Ring with 12 WS2812 5050 RGB LEDs (BerryBase link)
NeoPixel Jewel with 7 WS2812 5050 RGB LEDs (BerryBase link)
DFRobot FireBeetle ESP 32 IoT Microcontroller (Link, click me)
Lithium Pouch Cells or 18650 Cells with holders… Anything works (example)
SEAFRONT WALFRONT4qyo1h6ew2 PowerBank PCB (AZN DE, AZN CA)
Some kind of toggle switch, A thin and flexible USB C extension (the flat silicone cable ones for ex.) and USB C angle adapters (the smaller the better, check that they are made for PD/QC)
Resistors… 300 to 500 Ohm for the neopixel data wire

LED Rings knotted to the mesh with fishing wire

The Assembly… It is finally time to puzzle the pieces together.

WoemmeoW todo

Here are some pictures of the finished assembly:

It is time to turn it on for the first attempt…

Planned ideas:

The idea is to make the helmet chargeable with flexible solar panels, since u r gonna wear it roof-up anyway
It should also use ESP-Now to sync up with the turnlights in the scooter
Some kind of Bluetooth/PMR intercomm..