Type-2 Fuzzy Disturbance Observer Based Terminal Sliding Mode Control for Spacecraft with Liquid Slosh and Flexible Structure

摘要

This paper proposed a terminal sliding mode control strategy based on a type-2 fuzzy disturbance observer (FDO) for the spacecraft with liquid slosh and flexible structure (SLF). The type-2 fuzzy logic system (FLS) has a better behavior than type-l FLS on handling the uncertainties. Firstly, the type-2 FDO was adopted to estimate the whole uncertainties which contains the perturbations caused by the liquid fuel slosh and flexible structure, the unknown elements of the model and the external disturbances. Next, the terminal sliding mode surface was designed to ensure the system stability and robustness. Then, the stability of the proposed control scheme was proved based on the Lyapunov stability theory. Finally, numerical simulations showed the effectiveness and advantages of the proposed method.