We describe a one-joint planar arm which repeatedly throws and catches parts on its surface, and we demonstrate that proper choice of the throw velocity and arm geometry guarantees that the part will enter a unique recurrent motion pattern from a large set of initial configurations. The resulting system resembles an open-loop stable juggler of polygonal parts. Combined with a simple 1-bit sensor, the system can be used as a parts feeder.
Kevin M. Lynch, Michael Northrop, Peng Pan