空间3-RPS并联机构工作空间与奇异位形分析  

Workspace and Singular Configuration Analysis of Spatial 3-DOF Parallel Mechanism

作　　者：高红卫[1] 王丽[2] 史革盟[1] 魏宏波[1] Gao Hongwei;Wang Li;Shi Gemeng;Wei Hongbo(Baoji University of Arts and Sciences, Baoji 721016, China;Shaanxi Polytechnic Institute, Xianyang 712000, China)

机构地区：[1]宝鸡文理学院,陕西宝鸡721016 [2]陕西工业职业技术学院,陕西咸阳712000

出　　处：《机械传动》2017年第11期65-71,152,共8页Journal of Mechanical Transmission

基　　金：陕西省教育厅基金资助项目(16jk1051);校级重点项目(ZK15012);宝鸡文理学院科研计划项目(ZK16042)

摘　　要：从空间3-RPS并联机构约束得到动平台位置坐标和姿态角之间的耦合关系,由此导出工作空间边界的解析式。用运动螺旋描述由运动关节连接的构件之间的相对运动,利用反螺旋的性质,得到分支运动螺旋系的反螺旋,它代表了分支对动平台的结构约束力。进而将机构发生奇异的条件转化为分析动平台运动螺旋系和约束螺旋系线性相关的条件,自然地将机构的奇异位形划分为运动学奇异和约束奇异,给出了两种奇异对机构性能影响的物理本质,并导出奇异位形的解析表达式。实例给出了奇异位形在工作空间的分布特征和对工作空间的分割状况。The coupling relationship between the position coordinate and the attitude angle of the 3-RPS parallel mechanism is obtained from the structure constraints of the platform. Thus an analytic expression of the workspace boundary is derived. The relative motion of a member connected by a motor can be described by motion screw. According to the property of the reverse helix,the reverse helix of the branch motion screw system is obtained,which represents the structure binding force of the branch on the moving platform. In turn,the singularity of the mechanism is transformed into the analysis of the linear correlation condition of moving platform motion screw system and the constraint screw system. Therefore the singularity of mechanism is divided into kinematics singularity and constraint singularity. The physical essence of the influence of the two kinds of singularity on the performance of the mechanism is given,and the analytical expression of the singular configuration is derived. An example is given to show the distribution characteristics of the working space and the division of the working space.

关 键 词：并联机构 工作空间 运动螺旋 奇异位形 

分 类 号：TH112[机械工程—机械设计及理论]