A controller design for spacecraft with control saturation under thrust misalignment

In this paper, an adaptive control approach combined with time-varying sliding mode technique is developed for attitude maneuver of a rigid spacecraft, in which multi constraints are simultaneous considered, such as thruster uncertainties including thrust misalignment and magnitude error, external disturbances, uncertainty of the inertia of the spacecraft, and even the control saturation. By explicitly considering the saturation magnitude of the available control input to the thruster, the maximum value of thrust is used in the designed control law. Finally Lyapunov stability analysis shows that the closed-loop system is stable and numerical examples illustrate that the effectiveness and robustness of using the proposed controller.