Many years ago I salvaged an ex-industrial robot that was being thrown out of the University research lab I was working in. A crime for sure but I could see why they were getting rid of it. The robot was a collection of metal and motors but little more. No electronics, no power supply, no software. A mere shell of a machine.
Over the last few years I've been nuturing it back to health, building and coding replacement hardware and software. I had to take a break from working on dada (as the robot is known) for quite some time, as I got very stuck on a tricky stepper motor control problem. Recently though I discovered an excellent Arduino library (Accelstepper) that more or less solved the problem for me. Enough so at least that a few weeks ago I got the robot to draw its first picture, which is rather abstract. Here's the sped-up video:
More on dada, including a scanned image of the final picture, and explanation of what is going on, can be found on dada's own site http://dada.soulwire.co.uk/
The dada project is a collaboration with Justin Windle.