Today Slashdot is running a story about hektor, a robotic graffitti artist. It is a computer controlled robot, driven by an Adobe Illustrator plugin that moves a spraycan over a wall and paints a desired pattern. The cute thing about it is that it uses a very nifty drive mechanism. Rather than using a traditional two dimensional gantry, it slings the paintcan in a harness between two independently controlled chains. I spent a short break before a meeting working on the control mathematics for a similar setup that used linear steppers. It’s not too bad, perhaps I’ll write up a quick similator using Python (and maybe PyGame) to test out the idea.

The whole topic reminded me of some work I did a while ago that was inspired by Don Lancaster called flutterwumpers. He had many nifty ideas about using Postscript to drive very simple machines drill circuit boards, route signs and the like. He uses some simple PostScript code to drive everything,
which makes it pretty cool (and cheap, given GhostScript).

Another interesting link is to the Free and Easy: CNC Machining project on SourceForge. These guys built a prototype dual rotary table which looks pretty nifty.