输入受限的挠性航天器全驱姿态饱和控制

For space missions such as space attack and defense, spacecrafts are usually equipped with high-power counter loads such as microwaves and lasers, thus future spacecrafts will need to be equipped with large-scale flexible solar panels. To solve the problems of external disturbances, actuator saturation, and vibrations of flexible attachments difficult to measure directly during attitude maneuver of flexible spacecraft, a fully actuated-based attitude control method for flexible spacecraft is proposed. First, a fully actuated attitude model for flexible spacecraft is established. Second, a robust attitude control algorithm against saturation is designed based on the extended nonlinear observer (ENO) and Nussbaum gain adjustment. The external disturbances, flexible vibrations, and the approximation error of the input saturation function are considered composite disturbances, which are efficiently compensated by the nonlinear disturbance observer. Based on the direct parametric design of linear control parameters, the ENO is responsible for the real-time estimation and compensation of nonlinearities such as flexible vibrations generated by the flexible spacecraft. And the Nussbaum function is used for the adjustment of the controller output torque magnitude to avoid actuator saturation. The stability of the closed-loop system is rigorously demonstrated using the Lyapunov method. Finally, it is verified by mathematical simulation that this method can not only realize the attitude control under the actuator saturation constraint but also effectively suppress the flexible vibrations, which contributes to exploring a novel method for the attitude control of spacecraft with large-scale flexural attachments in the future.