Application of sliding mode dynamic surface control in fast steering mirror

A sliding mode dynamic surface control(SMDSC)strategy was proposed in order to solve the uncertain interference problem which may influence the tracking precision and the response time of the fast steering mirror (FSM)system, due to the external environment and the mechanical inertia and electromagnetic inertia of the voice coil actuator in the course of acquisition, tracking and pointing in FSM system. The controller introduces the tracking differentiator (TD) to instead the first-order filter in the traditional dynamic surface control, which improves the problem of unsatisfactory convergence speed and control precision of the first-order inertial link. Besides, the controller which combines sliding mode control with dynamic surface control further improves the anti-interference ability and tracking accuracy of the system. A large number of simulation studies show that, compared with the traditional dynamic surface control and classical proportional-integral-derivative (PID) control, the designed SMDSC increases by 62.5%, 75% respectively in the response time, 72%, 88% respectively in the adjustment time, and 75%, 96% respectively the tracking accuracy.