The electronics for this helmet initially seemed daunting but turned out to be a really rewarding part of the build. I used an Arduino UNO and 5 MAX7219 chips to control the lights. I started by deciding on how many LEDs I wanted in the visor. I chose 5 8×8 matrices of 5mm LEDs (320 in total). I then used skethup to design an LED holder that would fit perfectly into the helmet. I went through around 5 variations till I was happy. Luckily my friend has access to a laser cutter and he kindly cut it for me free of charge from 1mm PET plastic.
I then ordered the leds and began soldering them together. Details on the matrix assembly may be found here:
I painted the backs of the LEDs black and the front of the LEDs in a matt gloss to aid light dispersion.
I made cardboard top and bottom plates and began to solder the rows into an 8×8 matrix. I made sure to solder them in place so as to accommodate for the curvature of the visor.
Once all 5 had been assembled I soldered together 5 MAX7219 chips. These chips are cheap and allow an Arduino UNO board to control a matrix with just 3 pins. They can also be daisy chained together to make larger displays. I tested each individually to make sure it was working. I used 27kohm resistors in the boards to avoid overloading the LEDs. A good article on sizing your resistors can be found here:
I played around for ages trying to find a good code to use online. I’m still very much an Arduino beginner. I eventually found a fantastic code here:
This code is the best way to use MAX72XX chips and an Arduino to produce daft punk animations. Once the matrix was working correctly I made some sidebars from some leftover white LEDs from a previous project. I used cardboard, coloured plastic and hot glue to fabricate them. I came up with a rudimentary code that would cause the LEDs to flash randomly. All lights are controlled by the same Arduino board.
Once these where fixed to the main matrix assembly the electronics where basically complete. I would like to add some buttons later on to control the light displays. A short video of the final piece is here: