Globally adaptive decentralized control of time-varying robot manipulators

Abstract

In this paper, we develop a globally adaptive decentralized control scheme of time-varying robot manipulators for trajectory tracking control. Since the proposed adaptive control law is in a decentralized manner, only low-cost hardware is required for implementation. Furthermore, even of the time-varying parameters of the robot manipulator change arbitrarily fast, both the position and velocity tracking errors of the manipulators will converge to zero after employment of the proposed adaptive control law. For practical implementation, the adaptive law can be combined with a leakage term so that there is no chattering in the motion of the manipulator but at the price a residual set of the tracking errors as mentioned above, of which the size can be however made smaller by use of some larger design parameters. Finally, in order to illustrate the performance of the proposed scheme, simulation results are also provided, which turn out to be quite satisfactory.