考虑摩擦与间隙的空间机械臂轨迹跟踪控制

Trajectory tracking control of space manipulator considering friction and clearance

以空间机械臂在轨服务的高精度要求为背景,研究不同重力环境下考虑摩擦与间隙的空间机械臂轨迹跟踪控制。以二连杆空间机械臂为研究对象,建立基于轻杆模型的含间隙等效模型,使用Kane方程、力矩平衡原理建立摩擦模型,并运用拉格朗日方程建立机械臂动力学方程,设计无模型控制器。在此基础上分析不同重力环境下摩擦与间隙对机械臂关节驱动力、机械臂末端轨迹跟踪精度的影响,并与比例微分(PD)算法控制的机械臂末端轨迹跟踪效果相比较,验证在不改变控制器参数与结构的条件下,在不同重力环境下无模型控制算法的优越性。

Based on the high precision requirements of space manipulator in orbit service,the trajectory tracking control of space manipulator considering friction and clearance in different gravity environments is studied.Taking two link space manipulator as the research object,the paper establishes the equivalent model with clearance based on light bar model,establishes friction model by using Kane equation and moment balance principle,and establishes the dynamic equation of manipulator by Lagrange equation.The controller without model is designed.On this basis,the driving force of friction and clearance to the joint of the manipulator and the trajectory tracking accuracy of the end of the manipulator are analyzed under different gravity conditions.The tracking effect of the algorithm is com-pared with the tracking effect of the robot arm end controlled by proportional derivative(PD)algorithm.The supe-riority of the model control algorithm is verified under different gravity conditions without changing the parameters and structure of the controller.