针对具有外部扰动与参数不确定或未知的情况,讨论漂浮基柔性空间机械臂系统的协调控制与柔性振动抑制问题.基于假设模态法对柔性臂杆进行近似描述,并利用第二类拉格朗日方程与系统动量守恒关系,推导带外部扰动的漂浮基柔性空间机械臂系统的动力学方程.以此为基础,提出漂浮基柔性空间机械臂系统协调运动的非线性鲁棒控制与非线性鲁棒自适应控制方案.此两种控制方案均可克服外部扰动对系统的影响,控制漂浮基柔性空间机械臂系统载体姿态与机械臂各关节铰完成期望的协调运动,同时有效地抑制了臂杆的柔性振动.除此之外,非线性鲁棒自适应控制方案还可以解决系统惯性参数不确定或未知的问题.系统数值仿真结果证实了所提控制方案的有效性和可行性.
The coordinated control and vibration suppression problems of free-floating flexible space manipulator system with external disturbances and uncertain or unknown parameters are discussed. The flexible links are approximated based on the assumed mode method, and then with the second Lagrange approach and the linear momentum conservation, the dynamic equations of free-floating flexible space manipulator system are derived. Nonlinear robust control and nonlinear robust adaptive control schemes are proposed for coordinated motion of the free-floating flexible space manipulator system. These control schemes can all overcome the effect of external disturbances on the free-floating flexible space manipulator system and control the base attitude and the joints to complete the desired coordinated motion, while suppressing flexible vibration of the links efficiently. In addition, the nonlinear robust adaptive control scheme can also solve the uncertain or unknown problem of system inertial parameters. Numerical simulation is carried out to verify the validity and feasibility of the proposed control schemes.