二自由度平移并联机器人空间静刚度分析  

Spatial Static Stiffness Analysis of 2-DOF Translational Parallel Robots

作　　者：彭斌彬[1] 李增明[1] 武凯[1] 孙宇[1] 

机构地区：[1]南京理工大学机械工程学院,江苏南京210094

出　　处：《南京理工大学学报》2012年第3期522-528,共7页Journal of Nanjing University of Science and Technology

基　　金：中国博士后科学基金(2011M500923);江苏省'六大人才高峰'项目(2011ZBZZ025);江苏省前瞻性联合研究项目(BY2010107)

摘　　要：为提高一种二自由度平移并联机器人机构静刚度分析的准确度,该文建立了六维空间静刚度模型,并对主刚度及主方向做出评价。考虑机构的驱动刚度、结构刚度和空间外载荷3个因素对整机静刚度产生的影响,对机构的支链和滚珠丝杠进行静力学分析,求出它们的变形。采用虚拟机构法并根据输入输出之间的速度映射关系分别得到支链和滚珠丝杠引起动平台产生的位姿变形,再由小变形叠加原理推导出机构的整体变形。根据空间外力及外力矩与机构整体变形之间的关系,建立机构的整体空间静刚度模型。基于正交变换法,分析机构的最大最小线位移和角位移刚度的特性。研究结果表明该二自由度平面平移并联机器人机构的静刚度是空间六维的,沿导轨轴线方向的静刚度具有各向同性,垂直于导轨轴线方向的静刚度与其位置有关。To improve the accuracy of static stiffness analysis for a kind of two-degree-of-freedom （DOF） translational parallel robot, a six-dimension space static stiffness model is established,and the main stiffness and main direction are evaluated. Considering the effects of the driving stiffness, structure stiffness of the mechanism and spatial external load on the static stiffness of the mechanism, the compound limbs and ball screws of the mechanism are analyzed by the static analysis, and the cor- responding deformations are calculated. The pose deformations of the moving platform caused by compound limbs and ball screws are obtained using the virtual mechanism method and according to the velocity mapping relation between input and output. The total deformations of the mechanism are derived through the superposition principle at small strain. According to the relationships between the spatial external load and the total deformation of the mechanism,the total spatial static stiffness model of the mechanism is established. The stiffness characteristics of the maximum and minimum angle displacement and line displacement for the mechanism are discussed based on the orthogonal transformation method. The results show that：the static stiffness of the two DOF planar translational parallel robot is six-dimension, the static stiffness along the axis of guide is isotropy, and the static stiffness perpendicular to the axis of guide is related to the position at the direction.

关 键 词：并联机器人 静刚度 虚拟机构法 叠加原理 正交变换法 

分 类 号：TP24[自动化与计算机技术—检测技术与自动化装置]