Vibration suppression and sliding mode attitude control of flexible spacecraft with unknown disturbance and uncertainty

For the issue of vibration reduction and attitude maneuver control of flexible spacecraft with disturbance and uncertainty, this paper presents a novel control scheme based on path planning and sliding mode control. By planning the desired angular acceleration of the maneuver path, appendages´ vibration induced by attitude maneuver is decreased effectively. Based on exponential reaching law, a novel sliding mode controller is proposed, which can achieve rapid attitude maneuver and alleviate chattering. Furthermore, an extended state observer for flexible spacecraft is designed to estimate the unknown disturbances and uncertainties so that the prior knowledge of the upper bounds on the total disturbance is not necessary for the controller design. Finally, simulation results demonstrate the effectiveness and robustness of the proposed control scheme.