Time-Optimal Control of Two Robots Holding the Same Workpiece

An algorithm is given which minimizes the time for two robots holding the same workpiece to move along a given path. The unique feature of these systems is that they have more actuators than degrees of freedom. The method can be applied to any constrained robot system, including the case where one robot arm moves in contact with a surface. In addition to finding the optimum torque histories, the algorithm determines the optimum contact force between the each robot and the workpiece throughout the motion. Constraints on these internal forces are easily introduced into the algorithm.