Robust fault tolerant tracking control for the multi-joint manipulator based on operator theory

Abstract

Uncertainties and fault signals usually exist in the real systems and it is difficult to maintain stability and tracking performance for the real applications. Therefore, it is important to study the robust fault tolerant tracking control (RFTTC) for uncertain nonlinear feedback systems (NFS). Generally, the RFTTC schemes are designed for the uncertain NFS by using operator theory based robust right coprime factorization (ORRCF) method. In details, firstly, one novel RFTTC scheme is proposed for the uncertain NFS, wherein the fault tolerant controllers as well as the tracking one are designed based on the internal model. Secondly, the other new RFTTC scheme is proposed where the robust fault tolerant controllers are combined with the compensation operator and the tracking controller. By the proposed two design schemes, the impacts induced by the faults on the system is eliminated, and the entire nonlinear feedback system holds strong robustness and perfect tracking performance. Finally, simulation results of the multi-joint manipulator are used to indicate the validity of proposed two design schemes.