无寄生运动非对称空间2T1R并联机构设计与运动学分析  

Design and Kinematics Analysis of Asymmetric 2T1R-type Spatial Parallel Mechanism without Parasitic Motion

作　　者：邓嘉鸣[1] 许可[1] 赵迎春 沈惠平[1] 张震[1] 杨廷力[1] DENG Jiaming;XU Ke;ZHAO Yingchun;SHEN Huiping;ZHANG Zhen;YANG Tingli(Research Center for Advanced Mechanism Theory, Changzhou University, Changzhou 213016, China)

机构地区：[1]常州大学现代机构学研究中心,常州213016

出　　处：《农业机械学报》2018年第6期408-417,共10页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(51475050;51375062);江苏省重点研发计划项目(BE2015043)

摘　　要：根据基于方位特征方程的并联机构设计理论与方法,设计了一种能实现空间两平移一转动(2T1R)且无寄生运动的非对称并联机构(RPa‖3R)-R+RSS。对该机构进行了动平台方位特征(POC)、自由度(DOF)以及耦合度κ计算的拓扑特性分析,表明机构为零耦合度且具有部分运动解耦性;运用序单开链法的运动学原理,推导了求解机构位置正反解的解析式;基于位置反解,分析了机构的位置工作空间形状与大小及其转动能力;探讨了机构发生奇异位形的条件;对机构的速度和加速度进行了计算及仿真分析。结果表明:该机构运动学分析简单,转动能力强,动力学性能较好。3-DOF parallel mechanism （PM） is widely used in manufacturing since, which is simple and flexible. According to the PM design theory and method based on the position and orientation characteristic （POC）, a novel two-translation and one-rotation （2TIR） asymmetric spatial PM without parasitic motion, RPo ｜｜ 3R -R ＋ RSS, was designed. Firstly, the topology characteristics of the PM were analyzed, including POC of the platform, the DOF and the coupling degree K） , which demonstrated that the PM was zero coupling degree and of partially decoupled motion. Secondly, the analytical modeling of the forward and inverse position solutions was derived by using kinematics method based on ordered SOC units. ＂In addition, the direct and inverse kinematics were verified by numerical methods using Matlab. And then the shape and size of workspace and rotation capability of the PM were analyzed. Finally, conditions of singularity of the PM were discussed, and velocity and acceleration of the PM were calculated and simulated. This PM had advantages of simple structure and easy manufacturing, which can be used to convey, assemble and position operations in manufacturing. The analysis results indicated that the kinematics analysis of the PM was not complicated, the rotation capability was strong and the performance of dynamics was better.

关 键 词：并联机构 零耦合度 寄生运动 运动解耦 两平移一转动 

分 类 号：TH112[机械工程—机械设计及理论]