Prescribed Performance Fault-Tolerant Tracking Control of Uncertain Robot Manipulators with Integral Sliding Mode

Abstract

This paper develops a fault-tolerant tracking control (FTC) for robot manipulators with prescribed performance subject to uncertainties and partial loss in effectiveness of actuators (UPEAs). First, an integral sliding manifold without reaching phase is constructed for guaranteeing the prescribed performance in both the transient and steady states. With this integral sliding manifold, an FTC is proposed for uncertain robot manipulators to obtain advanced tracking performance with prescribed performance constraints under the effects of UPEAs. The stability analysis is guaranteed by the Lyapunov theory and a homogeneous technique. The primary contributions of our design are as follows: (i) the proposed approach removes the reaching phase completely for the sake of the prescribed performance and better chattering-restraining capability; (ii) the nominal control part is also removed in the formulation of the conventional integral sliding mode, and then the proposed approach eliminates the algebraic loop problem; (iii) a simple control structure is accomplished to eliminate the effects of time delay and computational burden. A simulation, along with experiments, is completed for verifying the effectiveness of the proposed approach.