TIME-OPTIMAL CONTROL OF MULTIPLE COOPERATING MANIPULATORS WITH TRAJECTORY AND MOTION PROGRAM CONSTRAINTS

Two types of problems associated with time-optimal control of multiple manipulators moving a commonly held object along specified trajectori es are studied. The first problem involves finding the minimum traveli ng time and the optimal control torques for any desired motion program s of the given trajectory. The second problem involves finding the opt imal velocity distribution along the trajectory such that the motion c an be completed in the minimum time. To solve these problems, a parame tric form of the generalized dynamic equation is derived. An iterative search procedure is developed for solving the first problem. During t he search, the lower bound of the traveling time at any point of the g iven trajectory is determined by using the linear programming techniqu e. The second problem is solved by integrating the parametric dynamic equation along the given trajectory based on the phase-plane switching curve approach. The maximum acceleration and the upper bound of the o peration speed at each integration instance are determined from two li near programs. The proposed methods are applicable to various complex multi-robot systems and can handle nonlinear torque-speed characterist ics of the joint actuators. (C) 1996 John Wiley & Sons, Inc.