Behold my latest masterpiece for Making Things Interactive, a dazzling demonstration of mechanical movements.
circuit driving the DC motor
pivot point made of pipe cleaner twisted and duct-taped to my rapid-prototyping rig (aka my desk)
string harness holding wooden dowel
Unrelated to the final device, this is an earlier attempt at creating a Geneva drive out of bristol board, Q-tips, and foamcore. When the disc turns, it moves a pin affixed to its surface. That pin threads through a slot in the wheel, turning the wheel intermittently. However, on the next disc revolution, the pin doesn't quite line up with the next slot on the wheel. When it comes to making wheel and gear mechanisms, precision is important.