DETERMINING MAXIMUM PAYLOADS FOR COOPERATING ROBOTS UNDER TIME-OPTIMAL CONTROL

This work presents an algorithm which evaluates the dynamic performanc e limit of a cooperating robotic system using movements planned for mi nimum time. Minimum-time movements characteristically require that a s et of motors in the robot be driven at their maximum torque throughout the motion. These movements are limited by the combination of motor p erformance, mechanical advantage of the kinematic chain, and the locat ion of the start and goal positions. By increasing the payload for a m otion until a minimum-time solution is no longer feasible the payload limit of the system for the associated path is obtained. To illustrate the algorithm a detailed analysis of a robotic arm developed at Odeti cs Inc. is presented. The analysis includes numerical results for coop erating Odetics robotic arms using their maximum payload under time-op timal control. Furthermore, the maximum payload for the cooperating ro botic system to perform the same motion with a 1 sec time constraint i s determined.