Fly-Around Control of Space Tumbling Target Under Multiple Constraints

Aiming at the practical problems of external unknown disturbance and internal modeling uncertainty, when space tumbling target flies around in close range, a sliding mode controller (SMC) based on active disturbance rejection control (ADRC) technology is proposed to realize real-time estimation and compensation of “total disturbance.” Firstly, according to the motion characteristics of space tumbling target, the relative motion equation in rotating line of sight (RLOS) coordinate system is established; Secondly, the compound controller is designed, and the convergence of the nonlinear state expansion observer and the stability of the closed-loop system are analyzed based on the root locus method and Lyapunov function method respectively; Finally, the simulation results show that the SMC based on ADRC technology can effectively suppress the disturbance and overcome the chattering problem of traditional sliding mode controller. It has a good control quality, and strong robustness is an easy method for engineering practice.