基于旋量理论的机器人误差建模方法

Screw theory based error modeling method of robot mechanisms

摘要:

在现代旋量理论使用矩阵指数以及指数积表示刚体运动的基础上,将机器人关节轴线的位姿误差等效为假想广义运动副旋量运动的结果,从而建立机器人含误差旋量的运动学指数积模型.将工具坐标系的位置和姿态误差分别等效为移动副和转动副旋量运动,给出了其大小及方向的计算公式.在Matlab环境下编制了旋量计算软件包,以SCARA机器人为例,应用该软件包进行了误差仿真分析,并使用Adams软件进行了仿真验证.结果表明,该误差建模方法正确、有效.

Abstract:

Based upon the exponential matrix and exponential products of modern screw theory for the description of rigid body transformation,the pose error of kinematic pair axis is treated as the result of equivalent screw motion,and an error model of robot is built by using the products of exponentials formula.Meanwhile,the position and orientation errors of tool tip are represented as prismatic and revolute pair’s screw motions respectivly,and the calculation formulas are presented.Using SCARA robot as an example,the simulation experiment is done with Matlab and Adams,and the results show that the presented modeling method is intuitive and correct.