Attitude Exponential Stabilization Control of Rigid Bodies via Disturbance Observer

The attitude stabilization problem of rigid bodies with external disturbance is studied. A novel disturbance observer-based control scheme is presented. Comparing with the existing observers for external disturbance, the proposed observer releases the assumption that the external disturbance should be constant or with the minor rate of change. The closed-loop attitude stabilization system is governed by the controller to be exponentially stable with disturbance rejected. The observer error of disturbance, the attitude, and the angular velocity are exponentially stabilized to be zero or within a small set with an arbitrary radius. The key feature of this scheme is that it ensures the control performance to be more robust to any external disturbance. The controller has a simple structure and does not involve complicated computation. The effectiveness of the presented solution is validated by a rigid satellite example.