空间曲线平移并联机构构型综合与分类

Type Synthesis and Classification of Space Curve Translation Parallel Mechanisms

针对现有机构分析与综合理论方法存在综合结果不完整、无法适用于弯曲平移机构等问题,提出了空间曲线平移并联机构构型综合及分类方法。首先,借鉴高斯非欧几何的内蕴思想,将直线、曲线、平面以及曲面等均视作可描述末端构件平移特征的独立空间,进而建立了可描述弯曲平移运动特征的表达模型;其次,研究了支链末端构件弯曲平移运动的形成机理,并制定了相应的运动特征求并运算规则;然后,根据形态特征将空间曲线平移并联机构划分为9种基本类型;最后,以柱柱相贯线平移机构和柱锥相贯线平移机构为例,给出了空间曲线平移并联机构的构型综合方法。

Topological structure synthesis is the most original part of mechanical system design. Aiming at the problems in the existing theories on type synthesis of robot mechanisms,such as incompleteness of synthesis results,inapplicability to bending translation mechanisms and so on,the method of type synthesis and classification for parallel mechanisms with bending translation motion characteristic was proposed. First of all,lines,curves,planes and surfaces were regarded as independent spaces based on the Gauss non-Euclidean intrinsic geometry,which can be used to describe the translation characteristics of the end-effector. Then a motion characteristic model of bending translation was established,which included motion type( translation and rotation),motion direction,dimension and overall geometric shape of motion space. Secondly,the forming mechanism of bending translation was studied,and the relevant operation rules of bending translation motion characteristics were formulated,which made the intersection of all limbs’ motion characteristics for parallel mechanism relatively straightforward and simple. After that,according to the geometric morphological features of space curves,the space curve translation mechanisms can be divided into nine basic types. Finally,the method of type synthesis for space curve translation mechanisms was illustrated by two examples,and the complete procedures for structural synthesis of cylinder-cylinder intersection line translation mechanism and cylinder-cone intersection line translation mechanism were shown by using this method.