Attitude stabilization for flexible spacecraft with inertia uncertainty by a sliding mode control law

In this paper, attitude control for a flexible spacecraft with inertia uncertainty is considered. First, an adaptive law is constructed to estimate the upper bound of a certain function of the inertia uncertainty. Then, based on the proposed adaptive law, an adaptive sliding mode control law based on state feedback is established for the case while the flexible modal variables are measurable for the flexible spacecraft with inertia uncertainty. To verify the effectiveness of the presented control laws, simulations are performed in the presence of inertia uncertainty. Simulation results show that the proposed control laws attenuate the effect of inertia uncertainty successfully and the attitude states can be stabilized by the proposed sliding mode control laws.