Interval Type‐2 Fuzzy System‐Based Actuator Failure Compensation Control Using Adaptive Command Filtered Backstepping Approach

ABSTRACT An interval type‐2 fuzzy system (IT2FS)‐based actuator failure compensation strategy is introduced for nonlinear systems including uncertain dynamics, unknown control direction and actuator failure. The proposed compensation scheme deals with lock‐in‐place and total or partial loss of effectiveness failures, simultaneously and uses IT2FS to model uncertain functions and uncertain changes obtained due to the actuator failures. Also, to handle the unknown control direction arising because of the unknown control coefficient and uncertain loss of effectiveness failure, the Nussbaum function idea is invoked. After that, the proposed scheme is designed using adaptive command filtered backstepping (CFB) approach. The suggested scheme eliminates the explosion of terms as well as difficulties in selecting the time constant of filters in the dynamic surface control (DSC) and compensates filtering errors. The presented compensation approach assures boundedness of the closed‐loop signals. Finally, simulation and comparison results on two different applicable examples under different actuator failures are presented to highlight the effectiveness and performance of the presented approach.