Suspension nonlinear analysis and VSS-LMS adaptive filtering control of satellite borne flexible structure

Abstract

Satellite borne flexible structure is a multi-degree-of-freedom system, which contains complex dynamic characteristics such as time-varying parameters, geometric nonlinearity, gap nonlinearity, and so on. Flexible structure suspension typically results in geometric nonlinearity.The oscillation equation with nonlinear term is established according to the law of motion of a nonlinear pendulum and considering the influence of medium swing angle and lateral force. The perturbation approach is used to get the relationship between vibration frequency and the nonlinear term, and the impact of factors on vibration characteristics is investigated. The satellite borne flexible structure's active vibration control(AVC) system is then established. Considering proportional differential(PD) or fuzzy control adjustment, variable step size least mean square(VSS-LMS) adaptive filtering algorithm is used to calculate the control signal, and considering the influence of geometric nonlinearity, the actuator is used to suppress the vibration of the satellite borne flexible structure. Finally, the vibration response's amplitude under steady-state excitation significantly decreases as an outcome of the vibration control simulation.