对称3T1R并联机构构型设计与位置分析

Configuration Design and Position Analysis of Symmetrical 3T1R Parallel Mechanisms

基于螺旋理论,深入研究了一种适用于轻小物料高速操作的3T1R运动机构—全对称4-URU并联机构。首先应用螺旋理论对能实现3T1R运动的全对称并联机构进行型综合,列举出了支链中仅含R副的3T1R机构,考虑机构的结构复杂度、工作空间和力/运动传递性能,优选出了一种综合性能较好的4-URU并联机构,验证了优选机构的自由度特征,建立了位置正逆解数学模型,搜索求解了工作空间,结果表明该机构工作空间体积较大,各向同性度较好。

Based on the screw theory, a fully symmetric 4-URU parallel mechanism with 3T1 R motion is studied. In this paper, first of all, the screw theory is applied to synthesize all symmetric parallel mechanisms that can realize 3T1R motion, and the 3T1R mechanisms with only R pairs in the branch chains are enumerated, considering the bearing capacity, workspace and isotropic performance of the mechanism, a 4-URU parallel mechanism with better comprehensive performance is selected, then the degrees of freedom of the mechanism is verified, the forward and inverse solution mathematical model is established, and the workspace of the mechanism is solved by searching. The results show that the workspace of the mechanism is large and isotropy is good.