Title: Fuzzy sliding mode fault tolerant control for a class of perturbed nonlinear systems

Authors: Faten Baklouti; Sinda Aloui; Abdessattar Chaari

Addresses: Laboratory of Sciences and Techniques of Automatic Control and Computer Engineering (Lab-STA), National School of Engineering of Sfax, University of Sfax, P.O. Box 1173, 3038 Sfax, Tunisia ' Laboratory of Sciences and Techniques of Automatic Control and Computer Engineering (Lab-STA), National School of Engineering of Sfax, University of Sfax, P.O. Box 1173, 3038 Sfax, Tunisia ' Laboratory of Sciences and Techniques of Automatic Control and Computer Engineering (Lab-STA), National School of Engineering of Sfax, University of Sfax, P.O. Box 1173, 3038 Sfax, Tunisia

Abstract: This paper proposes an adaptive FTC approach which combines a sliding mode controller (SMC) and a proportional integral (PI) controller for nonlinear MIMO systems. The main contribution of the proposed method is that the structure of the controller system is partially unknown and does not require the knowledge of the bounds of uncertainties and disturbances. This method uses adaptive fuzzy systems to approximate the unknown nonlinear functions. Then, in order to reduce the chattering phenomenon without degrading the tracking performances, the discontinuous term in the conventional sliding mode technique is replaced by an adaptive PI term. According to Lyapunov approach, the dynamic tracking performance of the closed-loop system is optimised despite the presence of faults. Finally, the proposed method is applied to an inverted pendulum as a nonlinear SISO system and to a robot manipulator as a nonlinear MIMO system. It achieves satisfactory simulation results in both cases.

Keywords: fuzzy logic; SMC; sliding mode control; fault tolerant control; tracking control; nonlinear systems; fault tolerance; perturbation; PI control; MIMO systems; fuzzy control; chattering reduction; inverted pendulum; SISO systems; robot manipulators; robot control; simulation.

DOI: 10.1504/IJMIC.2016.076826

International Journal of Modelling, Identification and Control, 2016 Vol.25 No.4, pp.313 - 322

Received: 03 Mar 2015
Accepted: 20 Aug 2015
Published online: 01 Jun 2016 *

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