针对刚体航天器姿态机动控制问题,结合变速控制力矩陀螺(VSCMG)执行器的特性,提出一种自适应动态滑模控制律,提高了姿态机动控制的扰动抑制能力和鲁棒性。此控制律采用自适应方法对扰动力矩进行估计,通过给出控制力矩变化率并对其积分得到控制力矩,以此削弱切换控制的抖振对控制力矩时间连续性的影响,从而改善系统的动态性能。仿真分析显示该控制律能够在扰动力矩作用下实现刚体航天器的快速姿态机动,并且有效减弱了滑模控制的抖振现象。
An adaptive dynamic sliding mode control law is proposed in this paper for rigid body satellite attitude control using variable speed control moment gyroscopes (VSCMG) actuators to improve the robustness of the control system under disturbances. In the proposed control algorithm, the disturbance torque is estimated by using some kind of adaptive method. The differential signal of the control torque is used as the controller output rather than the actual control torque itself. Therefore, the chattering problem of the control torque caused by the high-frequency switching action would be softened through the integral operation, so that the dynamic performance of the control system could be improved. Numerical simulation shows that rapid? attitude maneuvers of rigid body satellites could be accomplished in the presence of external disturbance and the inherent chattering problem of sliding mode control could be softened.