Discrete-time high-order fully actuated robust stabilization control for a type of combined spacecraft subject to uncertainties

This paper investigates discrete-time high-order fully actuated (DT-HOFA) robust stabilization control for a type of combined spacecraft simulator (CSS) subject to nonlinear uncertainties. First, a discrete-time second-order fully actuated system (FAS) model is developed for the CSS system and generalized to a general DT-HOFA system (HOFAS) with nonlinear uncertainty, after which the robust control objective is proposed. Then, based on a linear matrix inequality condition, a robust stabilizing controller for the uncertain DT-HOFAS is designed under certain nonlinear uncertainties, which produces a closed-loop system with arbitrarily assignable eigenstructure. The assignable nature of the closed-loop system is further utilized to improve the system performance by solving a multi-objective optimization problem. Finally, the proposed approach is applied successfully to solve the robust stabilization control task of CSS with nonlinear uncertainties, and simulation and experimental results verify its convenience and effectiveness for practical use.