Comparative Analysis of Advanced Control Strategies for Vibration Control of Flexible Satellite Structures
Abstract
Flexible satellite structures with lightweight solar panels are naturally prone to structural vibrations caused by attitude maneuvers, continuous environmental disturbances and deformation during deployment. These vibrations can lead to a decrease in pointing accuracy, a degradation in payload performance, and an adverse effect on the overall stability of the spacecraft, thereby stressing the importance of effective vibration control. This paper presents a comparative study of advanced control strategies for a rigid-flexible satellite model with one flexible solar panel. A single state-space formulation was developed capturing the coupled rigid-body and flexible dynamics. All controllers were implemented under the same simulation conditions to allow for a direct and objective comparison. Three representative operating conditions are considered: residual vibration after an attitude maneuver, constant environmental excitation, and initial structural deformation. The performance of the controller was assessed based on tip displacement, tip velocity, control input, settling time, RMS displacement and control energy. The results obtained show that all investigated controllers are capable to stabilize the flexible satellite system but their dynamic characteristics are quite different. The LQR controller has relatively bigger vibration amplitude and longer settling time. The MPC provides balanced tradeoff between vibration reduction and control effort. ADRC achieves the best overall performance with faster attenuation of vibrations, lower residual oscillations and shorter settling times for all operating scenarios. It can estimate disturbances and so compensate quickly for transient and continuous disturbances, but requires a larger initial control action. In general, the proposed comparative framework provides a practical basis for the evaluation and selection of advanced vibration control strategies for flexible satellite structures.