A centrally-controlled grid of wind-sensitive tea candles.
I wanted to make a light-art piece for my barren walls at home to impress unsuspecting people who happened to stop by.
What it does
It generally looks like a grid of typical electronic tea candles, until you induce a wind current by blowing across the grid. The wind makes the candles wig out in a semi-natural manner.
What it’s made of
- Several 12-packs of non-flickering LED tea candles
- Wind sensors from Modern Device
- iCE40 FPGA
- Firmware written in C using MPLABX, compiled by XC32 and loaded using an ICD3
- Custom PCB designed in EAGLE and fabricated at PCBExpress
Theory of operation
I pulled the main workings from a brilliant Cornell ECE project created by Philip Ching. I added a 16-bit PWM matrix driver to the equation so the main loop can be reasonably responsive, and wiring becomes far easier. PIC32s with a crypto engine contain a very cool hardware (True and Pseudo) Random Number Generator, “TRNG” and “PRNG” respectively which we use to do flickery for all torches in the grid.