Sisyphus Testing Shoes by Dave Johnson

Dave Johnson -- creator of the Little Man automaton -- has made a second automaton feature Sisyphus. The engineering and motions are outstanding and the time-lapsed video is really cool.

From the YouTube description:

This time the Little Man is pushing hard on a railing, feet slipping constantly, and getting nowhere despite all the effort. Perhaps he is testing footwear. Or maybe he's just getting a feel for his futile future.

There are three movements, controlled from 3 axles, and the gears on the axles have prime numbers of teeth (23, 43, 59). So technically the movements will only repeat every 58,351 turns of the small gear. There's also a semi-random toggle on the head motion, so it will never really quite repeat.

Almost all the parts press fit and/or lock together, so the whole thing can be disassembled to a pile of parts, then reassembled, adjusted, and set going again without tools.

Check out set of still photos of Sisyphus Testing Shoes at flickr.

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