平面2R含铰间隙机器臂末端位姿精度建模仿真分析
Modeling and Simulation for End-pose Accuracy of Planar 2R Manipulator with Joint Clearance

由于多种不稳定因素对机器臂的影响,末端执行器往往会偏离理论作业位置,导致工作精度降低,其中机器臂铰接处存在的间隙对其运动影响很大。为了研究铰间隙对机器臂末端位姿的影响,采用D-H坐标系和位姿坐标变换法建立了机器臂逆运动学模型,用MATLAB获得广义坐标解析解,并由该广义坐标出发建立含间隙机器臂正运动学模型;采SolidWorks建立机器臂三维模型,分别对有、无铰间隙机器臂运动进行仿真及误差分析,得到机器臂作业时末端执行器的运动特性。结果表明,铰间隙对线性动态特性及角加速度有一定影响,特别是对线加速度和角加速度影响较大,使机器臂末端位姿存在偏差,降低了机器臂的运动稳定性与作业精度。
Various uncertain factors affect movement of manipulator, thus the end-effector tends to deviate from the theoretical position resulting in lower working accuracy, in which the joint clearance have an significant effect on the movement of manipulator. In order to study the influence of joint clearance to the pose accuracy of end-effector, the inverse kinematics mathematical model of the manipulator was established by D-H coordinate and coordinate transfer matrix method, getting the generalized coordinate equations with MATLAB, based on the present forward kinematics model; SolidWorks was used to establish the manipulator models and make error analysis and computer simulations of the manipulator with joint clearance and no joint clearance. At last, the movement characteristic of the end-effector is attained. The results and their analysis show preliminarily that the joint clearance has a certain effect on the linear motion characteristic and the angular acceleration, especially the linear acceleration and angular acceleration, which makes the pose of end-effector deviation, and reduces the motion stability and operation accuracy