Adaptive super-twisting sliding mode control for stabilization platform of laser seeker based on extended state observer

Abstract

In this paper, the stabilization platform of the seeker is analyzed to stabilize the photo-electric device by isolating the disturbances caused by vibration and turbulence from external conditions, as well as mechanical coupled torque, coiling, unbalanced torque and plant parameter uncertainty due to inner conditions. There are two important indexes to describe the performance of disturbance isolation, and these are the coupling coefficient and disturbance rejection rate. In order to improve the disturbance isolation performance of the stabilization platform of the seeker, an adaptive super-twisting sliding mode controller with an extended state observer is proposed. The adaptive super-twisting sliding mode control strategy is designed to achieve stabilized control of the stabilization platform of the seeker. The extended state observer is used to estimate and compensate for disturbances and model uncertainties. The stability analysis of the control strategy is discussed using Lyapunov stability theory. Simulation and experimental results are also presented to illustrate the effectiveness of the proposed control strategy. The proposed controller provides a better level of disturbance rejection compared to the conventional PI-DOB controller.