考虑杆件弹性变形的改进型Delta并联机构刚度特性分析  

Stiffness Characteristic Analysis of Modified Delta Parallel Mechanism Based on Bars' Elastic Deformation

作　　者：徐东涛[1,2] 孙志礼[2] 于晓光[1] 

机构地区：[1]辽宁科技大学机械工程与自动化学院,鞍山114051 [2]东北大学机械工程与自动化学院,沈阳110004

出　　处：《农业机械学报》2013年第5期294-298,共5页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家科技重大专项资助项目(2009ZX04014-014)

摘　　要：基于传统的机构刚度映射矩阵,建立了改进型Delta并联机构的刚度模型。模型不仅考虑了驱动铰链刚度和外载荷对机构刚度的影响,还考虑了构件重力和在约束力下杆件弹性变形对刚度的影响,更具有一般性和精确性。由于用刚度矩阵来评价机构刚度性能不够直观,提出了以机构弹性变形来评价机构刚度特性的方法。利用虚功原理计算出机构各个约束铰链上静态约束力,利用叠加原理计算出每个杆件约束反力和重力作用下的弹性变形量。然后,通过坐标变换法计算出机构的综合弹性变形量,进而分析了机构的刚度特性。Based on the traditional stiffness mapping matrix, a stiffness mapping model of modified Deha mechanism was established. The model considered both the influence of stiffness of active joints and external load and the influence of gravities factor and all parts＇ elastic deformation under the constraint force on the mechanism stiffness so that it was more general and exact than any other stiffness models. Evaluating the stiffness characteristic of parallel mechanism by stiffness matrix form was not intuitive. An idea was proposed to evaluate the stiffness performance by the elastic deformation of the mechanism. The static constrained forces of all joints were calculated by using the principle of virtual work. The elastic deformation under the constrained force and gravity was calculated by superposition principle. At last, the comprehensive elastic deformation of the mechanism was obtained by coordinate transformation method. The stiffness characteristic of the mechanism was further analyzed.

关 键 词：改进型Delta机构 刚度映射 刚度特性 弹性变形 坐标变换法 

分 类 号：TP242.2[自动化与计算机技术—检测技术与自动化装置] TH122[自动化与计算机技术—控制科学与工程]