Global asymptotic tracking of robot manipulators with a simple decentralised non-linear PD-like controller

Abstract

In this study, the authors address the problem of global asymptotically tracking control of uncertain robot manipulators with a simple decentralised non-linear proportional plus derivative like controller. The proposed controller is formulated with a decentralised structure without reference to modelling information and the control gains are easily determined based on some well-known bounds extracted from the robot dynamics, and thus it is easy to implement. The global asymptotic stability of the closed-loop system is shown with Lyapunov's direct method. Even when the proposed scheme is modified to avoid the possible chattering in practical implementation, the overall performance remains appealing. Simulations performed on a two degree-of-freedom robot manipulator demonstrate the effectiveness of the proposed approach.