TQW

Yipe! I discovered an orphan on my website. Rescuing now...

The Quoting, Whirled is a Burning Man project I did in 2002. It was a bunch of wooden paint-stirring sticks with LEDs attached to them, spinning ("whirling") around in the night and tracing out words using the persistence of vision illusion. I gathered the words ("quotings," get it?) through a webpage that friends and random strangers contributed to.

The development was intense, because I didn't know anything about digital circuit design at the time. Coming from a software background, I found it odd to have the edit-compile-debug cycle measured in weeks rather than seconds. The circuit was based on the Atmel AVR ATMega microcontroller. I used a hall sensor to detect when the apparatus had completed a revolution, which allowed it to time the advancement of columns in the display. There was an IR receiver on the board, but I didn't have time to implement the RC5 decoding needed to let people in the field control the displays with universal remotes.

Aside from the circuit design, the hardest tasks were sourcing parts and figuring out how to supply power to a rotating circuit. I solved the power problem by taking pairs of motors, taking one apart, and gluing its commutator-brush assembly onto the intact motor. That's the same approach that electric motors use to power up the electromagnets inside them.