Finite-Time Disturbance Observer Based Nonsingular Terminal Sliding Mode Control for Aircraft Active Side-Sticks

The active side-sticks can provide variable feedback force to the pilot compared with the traditional passive side-sticks, which makes the pilot's maneuvering comfort better. Aiming at the problem of poor control accuracy of position servo control under disturbance of active side-sticks, a global fast non-singular terminal sliding mode control strategy based on a finite-time disturbance observer is proposed. Firstly, a position servo tracking system model is established, and then, in order to achieve fast and accurate position tracking in the presence of disturbance, an observer-based nonsingular terminal sliding mode controller is proposed, and the stability of the system is proven. Finally, simulation experiments show that the controller converges quickly, can track the target position in a limited time, improves the robustness of the active side-sticks position servo system, and that the tracking error under disturbance is smaller than that of the three-closed-loop PID control.