并联机床支链刚度及载荷的确定方法

给出了并联机床各支链等效的非线性刚度及栽荷的确定方法。首先建立了考虑关节接触变形的并联机床数值分析模型，然后将实验获得的并联机床末端变形数据引入分析模型中，得到一组关于并联机床支链等效刚度的非线性方程组，并提出了非线性刚度矩阵的线性化求解方法。求得并联机床的支链刚度及栽荷后，将支链视为串联机构，可以进一步获得支链上各关节的刚度和栽荷，为并联机床整机的静态和动态性能分析奠定基础。实例计算结果表明了该方法的有效性。

Determination Method of Branch Stiffness and Load for Parallel Machine Tool

A method for determination of equivalent nonlinear stiffness and load of branchs on parallel machine tool is presented. In this method, numerical analysis model of parallel machine tool with joint contact deformation is first established and then, deformation data of the parallel machine tool ending obtained via the experiments are ushered in the analysis model so that a set of nonlinear equations concerning the equavalent stiffness of branch chain of parallel machine tool can be obtained. Also, the linearization method of the nonlinear stiffness matrix is used to obtain the solution. After the branch chain stiffness and load of parallel machine tool are obtained, the branch chain can be considered as the serial machanism, whereby the stiffness and load on each joint of branch chain can be further obtained in such a way as to lay a solid foundation for the static and dynamic characteristic analysis of the whole parallel machine tool. With a set of parallel machine tool as an example, the joint load is calculated. As compared with the literature result, this method is reliable and effective.