Robust Fuzzy Adaptive Fault-Tolerant Control for a Class of Second-Order Nonlinear Systems

Abstract

In this brief, an optimal active fuzzy fault-tolerant control (OAFFTC) scheme is proposed for a class of unknown perturbed multi-input multi-output (MIMO) nonlinear systems with nonaffine nonlinear actuator faults and time-varying sensor faults. The control strategy can handle automatically (online updating) with three additives (bias, drift, and loss of accuracy) along with one multiplicative (loss of effectiveness) sensor faults and nonlinear state-dependent actuator faults. In order to deal with uncertain system dynamics, sensor and actuator faults, and external disturbances, fuzzy systems (FSs) and backstepping techniques were combined to provide the adaptive control term as well as a robust control term. Butterworth filter is used to get rid the algebraic loop problem. The suggested robust term, can deal with approximation errors of the fuzzy systems (FSs). To automatically optimize the adaptive parameters and the starting conditions, particle swarm optimization (PSO) approach is introduced. The Lyapunov approach is employed to demonstrate the closed-loop system's stability. To assess the efficacy and correctness of the suggested scheme, quadrotor dynamic model is performed on the simulation part.