摘要
基于方位特征（POC）方程的并联机构拓扑结构设计方法提出了机构POC、自由度和耦合度等拓扑结构特征指标,用于揭示并联机构结构学、运动学和动力学的一些基本特性,但其人工计算、分析过程冗长、复杂、费时,所以研究了拓扑结构特征指标计算机自动分析软件的总体框架及其实现流程。首先,提出了能自动识别支链运动副轴线关系的并联机构字符串描述模型,以及支链POC集的矩阵描述模型;基于此描述模型,研究了POC集＂交＂和＂并＂运算规则的算法,给出了机构POC、自由度和独立位移方程数的自动分析流程;接着,给出了并联机构拓扑结构最佳分解路线的算法,制定了机构耦合度自动化分析的实现流程。最后,利用VC＋＋编程开发了程序,并对并联机构进行了实例计算,其结果与人工计算分析一致。该算法和程序有助于更多的机构学研究和设计人员,较易计算、分析并联机构的拓扑结构特征。
The theory and method of topological structure design for parallel mechanisms（ PMs） based on POC（Position and Orientation Characteristic） equation is created by Chinese scholars,which has been appreciated and applied gradually by other researchers home and abroad. The 12 topological structure characteristics proposed are innate topological invariants of a mechanism which reflect the essential features of structural theory,kinematics and dynamics.But the process of computation and analysis is complicated. In this paper,the principle,algorithm and implementation of computer-aided analysis software of PMs are studied. Firstly,a symbolic description which can auto recognize the order of the kinematic pairs and their orientation relations in the limb of PMs is presented,and a kind of matrix expression form is promoted to describe the POC set of limb. Then,according to the spatial dependence of the POC set element,the algorithms of union operation and intersection operation are proposed,and based on these algorithms the automatic analysis flow of POC set,the degree of freedom（ DOF）,and the coupling degree are presented. Finally,the automatic analysis software is developed with VC＋＋,and a case study is presented for a 3 T1 R parallel mechanism. The results show that the proposed union and intersection algorithms are effective and the method of structural decomposition is correct. The algorithms and program proposed are helpful to easily calculate and analysis the topological structure characteristics of PMs for more mechanism researchers and engineers.
作者
朱小蓉
黄骏
沈惠平
杨廷力
刘安心
杭鲁滨
ZHU Xiaorong;HUANG JunI;SHEN Huiping;YANG Tingli;LIU Anxin;HANG Lubin(Changzhou University,Changzhou,Jiangsu 213164,China;PLA University of Science and Technology,Nanjing,210007,China;Shanghai University of Engineering Science,Shanghai 201620,China)
出处
《机械设计与研究》
CSCD
北大核心
2018年第4期54-61,69,共9页
Machine Design And Research
基金
国家自然科学基金资助项目(51475050、51375062)
关键词
并联机构
拓扑结构特征
POC集
自由度
耦合度
计算机辅助分析软件
框架设计
parallel mechanisms
topological structure characteristic
POC set
DOF
coupling degree
computer-aided analysis software
framework design
