Robust time-optimal trajectory planning for robot manipulators

Abstract

In this paper, we propose an approach to solving the problem of robust time-optimal path tracking control to meet a prescribed tolerance in the presence of plant uncertainty. Our approach involves identifying the modelling errors as disturbances in joint accelerations and using a theory that relates such disturbances to the tracking performance of a robot under computed-torque control. The theory allows us to calculate the torque levels that need to be held in reserve and the controller gains that are required to reject the expected levels of disturbance. Our experiments show that if these levels of torque are held in reserve and if the controllers are tuned in this way, then the robot performs near time-optimal tracking meeting the specified tolerance for tracking accuracy.