多环耦合机构末端件自由度计算的等效法  

Equivalent Method of Output Mobility Calculation for a Novel Multi-loop Coupled Mechanism

作　　者：刘婧芳[1] 黄晓欧 余跃庆[1] 丁华锋 黄真[2] 

机构地区：[1]北京工业大学机械工程与应用电子技术学院,北京100124 [2]燕山大学机器人研究中心,秦皇岛066004

出　　处：《机械工程学报》2014年第23期13-19,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51105004);北京市教委科研计划面上项目(KM201310005016)资助项目

摘　　要：针对新型耦合机器人与常见并联机器人机构结构的迥异性,提出一种适应多环耦合机构末端件约束分析和自由度计算的新方法,此方法的主要思路是将多环耦合机构转化为并联机构。提出机构拆分原则,将连接输入和输出的部分拆分为多个独立单元体。应用螺旋理论逐一分析拆分出的单元体中各个耦合节点构件相对于机架的独立运动,将含耦合结构的独立单元体等效为一个串联分支,整个机构就等效为一个并联机构。分析等效并联机构各分支的运动螺旋系和约束螺旋系,采用二次反螺旋求得机构末端件的自由度。应用提出的等效替代法计算一个耦合机构的自由度,计算结果与原型一致,表明提出的新方法能够有效化简耦合机构的复杂性并正确求得自由度。In view of the different structures between novel multi-loop coupled mechanisms and common parallel mechanisms, a novel method is proposed for output constraint and mobility analysis of multi-loop coupled mechanisms. Converting a coupled mechanism into a common parallel mechanism is the main idea. A rule is given to split the connection between input and output into several independent elements. Relative motions of the coupled-nod link in every element are analyzed based on screw theory, and the element including coupled structure is ultimately equivalent to a serial chain. Thus the whole coupled mechanism is equivalent to a parallel mechanism. Limb twist systems and limb constraint systems of the equivalent parallel mechanism are analyzed, and the output mobility is calculated by re-solving the reciprocal screws of the constraint screws. The proposed method is applied to a typical coupled mechanism, and the computed result is in accordance with the prototype, which shows that the equivalent method can effectively simplify the complicated structure and get the correct mobility.

关 键 词：并联机器人 多环耦合机构 螺旋理论 自由度 

分 类 号：TH112[机械工程—机械设计及理论]