A study on variable gain sliding mode fixed-time strategy for aircraft electromechanical actuators

To improve the convergence speed of angular velocity tracking error, and reduce the input energy consumption of aircraft comprehensive control, a variable gain sliding mode fixed-time control method is proposed. Firstly, a nonlinear dynamic model driven by a permanent magnet synchronous motor as the core of the aircraft actuator was established, and a constant gain sliding mode fixed-time control algorithm was developed based on the motor control system; Next, to improve the shortcomings of fixed gain, an adaptive law adjustment controller with fixed-time convergence characteristics was designed to adjust the gain. A variable gain sliding mode fixed-time control algorithm was constructed, and the fixed time convergence of the closed-loop system was theoretically proved. Matlab numerical simulation has verified the strong robustness of the controller, as well as the advantage that the upper bound of trajectory tracking error convergence time is not affected by the initial value of the system states.