Experiments in Robotic Catching

Real-time coordination of visual information with high speed manipulator control is studied in the specific context of three-dimensional robotic catching. All path-planning for the catch occurs in real-time during the half-second that the targeted object is airborne. We use a trajectory-matching algorithm that combines an observer with a varying-strength filter, an error estimator, and an initial motion algorithm. The results are demonstrated experimentally using a real-time vision system and a four-degree-of-freedom, cable-driven arm with a workspace of 4.2 cubic meters and speed capabilities of up to 2.0 mls.