The Simulation of Time-Optimal Control For Robotic Arms

Abstract

This paper presents the simulation results for time-optimal control of robotic arms along specified paths. The implementation of time-optimal control consists of several problems: (1) the control is generally discontinuous (Bang-Bang), (2) the actuator dynamics are usually ignored to reduce the order of the system, and (3) the optimal control leaves no control authority to compensate for tracking errors caused by unmodelled dynamic and the delays introduced by the on-line feedback controller. To overcome these difficulties the motor dynamics are compensated for using a simplified friction model, and the dynamics of the feedback controller are accounted for using trajectory preshaping. The simulation results show the advantages of time-optimal control for reducing motion duration as well as for increasing tracking accuracy.