挠性航天器滑模变结构控制及抖振抑制研究

针对挠性航天器姿态滑模变结构控制中存在的抖振问题，提出了一种改进的滑模变结构控制律.在滑模“边界层”法的基础上，用更为光滑的“反正切”函数替代饱和函数，以抑制抖振.在滑模控制器的到达运动控制律中引入滞后因子以减小机动初始时刻控制所需的最大控制力矩，避免由此引起的挠性附件振动.仿真结果表明，所设计的改进滑模变结构控制律不仅能够有效抑制抖振，而且对航天器自身参数摄动具有良好的鲁棒性.

On Sliding Mode Variable Structure Control and Chattering Reduction for Flexible Spacecraft

In order to reduce the chattering of variable structure control for flexible spacecraft attitude, an improved sliding mode controller is presented. Based on the boundary-layer sliding mode controller, the more smooth “arctan function” is used to replace saturation function to reduce the chattering. The delay factor is introduced in the reaching-law of sliding mode controller to reduce the maximum control torque required by the system at the initial maneuver moment, which can avoid the vibration of flexible appendages. Simulation results show that the improved sliding mode controller not only can effectively reduce chattering but also has strong robustness against parametric uncertainties.