Application of adaptive sliding mode control based on HSMDO in stabilized platform

In view of the nonlinear, time-varying characters about the high precision photoelectric servo stabilized platform, a higher order sliding mode disturbance observer based on super-twisting algorithm (HSMDO) has been proposed, which could improve the system's precision through add the estimated disturbance to the input terminal of the controller. And to weak the chattering problem of sliding mode control, meanwhile retain the advantage of its fast response; not sensitive to the parameter variations and disturbances; without the need for online identification system, a new adaptive sliding mode controller has been designed. Lyapunov stability theory and finite time theory proved that the system could convergence in finite time. Simulation experiment results manifest that the system could track the given signal well with the HSMDO, and the angular position error of photoelectric servo stabilized platform could within an minimum value no matter low speed or high speed when adaptive sliding mode controller with the HSMDO has been used. Compared with the traditional sliding mode, adaptive sliding mode control with HSMDO can effectively weaken the system's chattering, and make the system have good robustness.