Fault-Tolerant Adaptive Control for a Class of Nonlinear Systems With Uncertain Parameters and Unknown Control Directions

This paper investigates the adaptive fault-tolerant control problem for a class of nonlinear systems with unknown control directions and uncertain parameters. To solve this control problem, the homogeneous domination method based on backstepping and fault-tolerant control scheme is applied to the uncertain nonlinear systems. First, a homogeneous domination-based adaptive control scheme using Nussbaum-type function is designed. Then, a fault-tolerant controller is proposed to deal with the actuator faults. The adaptive controller ensures that the closed-loop system is bounded, and all the states of the system asymptotically converge to 0. Finally, a simulation example is applied to demonstrate the effectiveness of the new designed adaptive fault-tolerant control scheme.