漂浮基双臂空间机器人关节运动的模糊变结构滑模控制

Fuzzy variable structure sliding-mode control for dualarm space robot to track desired trajectory in joint space

讨论了载体姿态、位置均不受控制的双臂空间机器人系统的控制问题.利用拉格朗日方法并结合系统动量守恒关系,建立了双臂空间机器人系统的非线性动力学模型.以此为基础,对双臂空间机器人关节运动的控制问题作了研究.考虑到空间机器人系统结构的复杂性及其某些参数的变动性,根据具有较强鲁棒性的滑模变结构控制理论,设计了双臂空间机器人关节运动的滑模变结构控制方案;为了克服滑模变结构控制器抖振的缺点,附加设计了一个模糊控制器,以便根据系统的输出来动态调节滑模变结构控制器等速趋近率的系数,从而既确保了系统的快速响应而又消除了原有的抖振.系统数值仿真证明了该控制方案良好的控制效果.

A kind of nonlinear dynamic model of dual - arm free - floating space robot systems is presented based on Lagrange method. Based on the result, the control problem for space manipulator to track the desired trajectory in joint workspace is discussed. Because of the high structure complexity and the parameter uncertainty of space manipulator systems, the scheme of variable structure sliding - mode control with better robustness to uncertainty and disturbance is proposed. Fuzzy controllers are designed at the aim of chattering reduction and rapid response. The fuzzy controllers can tune the sliding control law parameters automatically according to the relationship between system state and switching manifold. The effect of the controller is testified by computer simulation.