一种无汇交轴线对称三转动并联机构的运动分析  

Kinematics Analysis of a 3-DOF Symmetrical Rotational Parallel Mechanism without Intersecting Axes

作　　者：陈子明[1,2] 黄坤[1,2] 张扬[1,2] 丁华锋 黄真[1,2] 

机构地区：[1]燕山大学河北省并联机器人与机电系统实验室,秦皇岛066004 [2]燕山大学先进锻压成形技术与科学教育部重点实验室,秦皇岛066004 [3]中国地质大学,武汉430074

出　　处：《中国机械工程》2016年第9期1215-1222,共8页China Mechanical Engineering

基　　金：国家自然科学基金资助项目(51305381);高等学校博士学科点专项科研基金资助项目(20131333120006)

摘　　要：传统的三自由度转动并联机构(又称球面并联机构)一般都有一个转动中心,且这个中心点往往是分支间多个运动副轴线的汇交点,这种严格的几何条件给机构的加工制造带来很大的难度,制约了这类机构的应用。针对此,提出了一种无汇交轴线的对称三转动并联机构,其三个分支对称布置,分支内及分支间均无汇交轴线。对机构进行了位置反解,得到了机构四种对称的装配构型;从分支运动奇异、平台约束奇异和驱动奇异三个方面对机构进行了奇异分析;最后给定了一组尺寸参数,采用数值搜索的方法得到了机构的姿态工作空间。通过结果可以看出,该机构可以实现三维转动,具有较大的姿态工作空间,而且制造装配相对容易,具有很好的应用前景。The traditional 3-DOF rotational PMs also called as spherical parallel mechanisms（ SPMs） usually had a rotation center which was the intersecting point of multiple revolute joint axes. This strict geometric conditions were very hard to fulfill in the manufacture processes and would restrict further applications of this kind of mechanisms. Thus,a PM with three rotational DOF and no intersecting axes was designed herein.It consisted of three identical limbs distributed symmetrically without intersecting axes in or between limbs.The inverse kinematics was solved and four symmetrical assembly modes were obtained. Then the singularity of the mechanism was analyzed and classified into three types： limb singularity,platform singularity and actuation singularity. At last,its orientation workspace was studied. This mechanism can realize three dimensional rotations with large workspace and is easier for manufacturing and assembly,so it has broad application prospects.

关 键 词：三自由度转动 并联机构 汇交轴线 奇异 姿态工作空间 

分 类 号：TH112[机械工程—机械设计及理论]