IJCAS

Fault-tolerant control (FTC) of a non-affine system with uncertainties is one of critical issues in nonlinear control. In this paper, in the presence of unknown actuator failures, an event-trigger-based FTC scheme is proposed for such a nonlinear system with predefined performance. For actuator failures, a compensation mechanism is designed to alleviate their impacts. By utilizing a predefined performance function, higher tracking accuracy can be obtained. Meanwhile, an event-triggered mechanism with a time-varying threshold, depending on tracking error, reduces the number of communications for a controller-to-actuator channel. An adaptive event-triggered function is then proposed with the compensation mechanism to improve the self-adjusting ability of the triggered function. Also, extended state observers and tracking differentiators are utilized to reconstruct unknown dynamics of the system and to simplify high-order derivation of virtual control laws, respectively. The stability of the closed-loop system is analyzed by input-to-state practically stability. Finally, two simulation results are supplied to verify the effectiveness of the proposed control method.

Keywords: Active disturbance rejection control, actuator failures, event-triggered control, fault-tolerant control, uncertain non-affine system.