一种新型三自由度混联机构基于刚度性能的尺度综合方法  

Dimensional Synthesis of a Novel 3-DOF Hybrid Manipulator Based on Stiffness

作　　者：洪振宇[1] 张志旭[1] 许致华[1] 

机构地区：[1]中国民航大学,天津300300

出　　处：《中国机械工程》2014年第5期619-623,629,共6页China Mechanical Engineering

基　　金：中国民用航空局科技项目(MHRDZ201013)

摘　　要：对一种新型三转动自由度混联机构进行了概念设计与尺度综合研究,该机构是由一种两转动自由度并联机构与回转工作台通过转台轴承串联而成的,具有刚度高、结构简单等优点。在建立两自由度并联机构速度映射模型的基础上,基于雅可比矩阵的奇异值理论,以机构的刚度为评价指标,研究了该机构并联部分的尺度综合问题。采用约束坐标轮换法来寻求评价函数的最优解,讨论了各尺度参数对机构刚度的影响规律,并得出了在最优解处,两移动副是平行的,且移动副间的距离与动平台上两球铰间的距离相等的结论,进而验证了该方法的有效性。The conceptual design and dimensional synthesis of a novel 3--DOF hybrid manipulator were presented. The manipulator was composed of a parallel mechanism and a rotating platform. The parallel mechanism had two degrees of rotational freedom and was connected with the rotating platform through a turntable bearing serially. It had many advantages such as high stiffness, simple structure. Stiffness was taken as evaluation index and dimensional optimization of parallel part of the mech- anism was studied, which was based on velocity mapping model of the 2--DOF parallel mechanism and the singular value theory of Jacobin matrix. Constraint method of coordinate alternation was adopted to seek the optimal solution of the evaluation function. The influence law of scale parameters on stiffness of the mechanism was discussed. A conclusion is that two shifting pairs are parallel and the distance of shifting pairs is equal to the distance of the two ball joint on the moving platform in the optimal solution place. So the effectiveness of the method is proved.

关 键 词：概念设计 尺度综合 刚度 约束坐标轮换法 

分 类 号：TH122[机械工程—机械设计及理论]