柔性空间机械臂系统的双环积分滑模控制

摘要

This paper discussed the trajectory tracking and vibration suppression control problems of free-floating flexible space manipulator with an attitude controlled base.With the law of conservation of momentum,the Lagrangian principle was utilized to model the dynamics function of the flexible space manipulator incorporating the assumed modes method.Using singular perturbation theory,a slow subsystem describing the rigid motion and a fast subsystem corresponding to the flexible motion were obtained.Then,a composite controller for coordinated motion between the base＇s attitude and the manipulator＇s joints of flexible space manipulator system was designed.The slow-subsystem dual-loop integral sliding mode controller dominated the trajectory tracking of coordinated motion in the presence of unknown parameters.The fast-subsystem controller damped out the vibration of the flexible link by hierarchical fuzzy logic controller.Numerical simulation results illustrate that the proposed controller is reliable and effective.%讨论了载体位置不受控、姿态受控的情况下,漂浮基柔性空间机械臂关节运动及柔性振动主动抑制的控制问题。由系统动量守恒关系及假设模态法,利用拉格朗日方法建立了柔性空间机械臂的系统动力学方程,之后采用奇异摄动理论,将其分解为表示刚性运动的慢变子系统和柔性振动的快变子系统。以此为基础,针对慢变子系统———柔性空间机械臂的刚性运动,设计了系统参数未知情况下的双环积分滑模控制方案,以控制柔性空间机械臂的载体姿态及机械臂关节铰协调地完成各自在关节空间的期望运动;而对于快变子系统———柔性臂的振动,则设计了分级模糊控制方案