Application of low speed opto-electronic tracking systems based on sliding mode distutbance observer

Based on the influence of nonlinear factors on the low-speed performance of opto-electronic tracking servo systems, the system design was divided into two parts. All disturbance was equivalent to an equivalent input disturbance (EID) existed on the control input channel. A sliding mode disturbance observer (SDOB) was put up to observe the system state for the nominal mode. By using the state observe error to estimate EID and derived the stable convergence conditions of this observer by Lyapunov function. By designing the gain matrix and the feedback matrix, the convergence velocity of the observer was adjusted, and suppression of disturbance was realized. An adaptive acceleration controller was employed in the known dynamic part of the system, which compensates the underestimation of the disturbance further, ensures the accuracy and stability of the dynamic tracking system, and improves the adaptive robustness of the control system. Simulation and experiment results show the effectiveness of the proposed method.