The PetBots workshop for kids lets them build a working ArtBot from surplus and recycled motors and switches. A number of different devices can be created from the kits. However, some of the most fun are spinBots that use two markers as legs and a motor to spin robotic Spirographs to draw mathematical curves as they spin around in circles.
The robotic Spirographs were part of the offerings at the San Francisco Maker Faire 2010.
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