Backstepping-based Adaptive Attitude Stabilization of a Spacecraft

The problem of adaptive attitude stabilization for a rigid spacecraft with uncertain inertia matrix is addressed by means of backstepping technique. An adaptive attitude control scheme is constructed, which is independent of any prior information on the spacecraft inertia parameters. The modified Rodrigues parameter (MRP) is adopted as attitude variable. One salient feature of the proposed approach is that it allows integral control action, which can eliminate or reduce steady-state attitude errors in the presence of constant external disturbances. Simulation results for the derived adaptive controller demonstrate the efficiency of the proposed backstepping strategy in achieving stabilization for spacecraft with inertia uncertainty.