Tripod并联机器人工作空间完全解析与实验验证

Workspace Resolution of Tripod Parallel Manipulator and Experimental Verification

针对Tripod并联机器人工作空间一般用数值搜索方法研究,难以给出边界曲面准确表达的问题,提出一种曲面扫略分析与机械结构形位分析结合的方法来解析Tripod并联机器人的工作空间。以正逆解的算法为基础,得到并联机器人各单开链扫略空间范围及其包络曲面表达式,用三维软件布尔运算得出各支链公共的工作空间,在考虑虎克铰约束和杆件干涉的情况下,再依据机械结构形位分析得到机器人实际工作空间及边界曲面表达式,并对工作空间的奇异性进行了分析。通过三坐标测量仪器测出实际的工作空间与理论分析解析出来的空间进行对比来验证解析方法的正确性,从而为机器人机械结构参数设计和工作空间计算奠定基础。

Aiming at the difficulty of using accurate analytical formulas to represent the Tripod parallel robot workspace boundary surfaces,a method called surface-sweep analysis combined with the shape of mechanical structure analysis was proposed to give an accurate expression to the workspace of Tripod parallel manipulator. On account of the Tripod parallel robot,the geometric model of the parallel robot was set up and the architecture of the parallel robot and the driving mode of the parallel robot were introduced. Based on the algorithm of forward and inverse kinematics solution,the scope of sweeping space and envelope surface expression of this sweeping space considering one of the robot parallel＇s open chains were obtained. Then,the six envelope surfaces were drawn in sequence and the overlap part of the six sweeping space was solved. In 3-D software,the public workspace can be obtained by using boolean operation algorithm. Then,under the consideration of mechanical structure of shape analysis and physical constraints, the actual workspace and boundary surface expression of robot can be obtained.Furthermore,the singularity of the obtained workspace was analyzed. According to the comparison of workspace measured by the three coordinate measuring instrument and the workspace obtained by 3-D software,the validity of this analytic method was verified by using the error analysis method,which layed foundation for the next step to figure out the influence of mechanical parameters on the workspace and do some work on the size optimization of the parallel robot.