Adaptive Fuzzy Fault-Tolerant Control of Uncertain Euler-Lagrange Systems With Process Faults

• Published in: IEEE transactions on fuzzy systems Vol. 28; no. 10; pp. 2619 - 2630
• Main Authors: Zhang, Jin-Xi, Yang, Guang-Hong
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.10.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adaptive control; Adaptive fuzzy control (AFC); Adaptive systems; Euler–Lagrange systems; Fault tolerance; Fault tolerant systems; fault-tolerant control (FTC); Faults; Feedback control; Fuzzy control; Fuzzy systems; Observers; Process control; process faults; System dynamics; Uncertainty
• ISSN: 1063-6706; 1941-0034
• DOI: 10.1109/TFUZZ.2019.2945256

This article is concerned with the fault-tolerant control (FTC) problem for Euler-Lagrange systems subject to process faults that cause changes in the system dynamics. The possibly time-varying and discontinuous changes bring out a challenge for fuzzy approximation. To conquer this obstacle, a novel adaptive fuzzy FTC strategy is proposed in this article. First, a constraint-handling scheme is designed to ensure zero overshoot for certain signals. In this way, the resulting unknown term, composed of the signs of sliding surfaces, the bounds of faults, and model uncertainties, is both continuous and within a fixed form. Subsequently, adaptive fuzzy systems are adopted to approximate this unknown term for compensation. It is proved that the tracking performance and the boundedness of signals in the closed-loop system are guaranteed by the developed method. The simulation results further illustrate the established theoretical findings.