数控机床导轨结合部动态特性参数优化识别方法研究

数控机床结合部动力学参数识别是机床动力学分析中至关重要的一个环节。针对企业精密卧式加工中心动力学设计的需要,在对该加工中心导轨部件进行模态试验的基础上,提出了一种将模态实验数据与有限元分析模型相集成的导轨结合部动力学参数的优化识别方法。该方法以试验所得各阶模态频率与阻尼比为优化目标,在Matlab与Ansys的集成环境下建立优化任务,采用基于Armijo搜索准则的拟牛顿BFGS算法对结合部动力学参数优化计算。导轨结合部动力学参数优化识别结果表明,所提出优化识别算法的收敛性好、精度能满足工程应用需要。

An Optimum Identification Method of Dynamic Characteristic Parameters of Guideway Joint on a NC Machine Tool

Identification of joint dynamic characteristic parameters is one of the most important parts of machine tool dynamic analysis. To satisfy the dynamic design requirements for a precision horizontal machining center in an enterprise class application, an optimum identification method is proposed. Based on the modal test of a linear guideway, this method aims at integrating modal test data into the finite element analysis. Adopting the modal frequencies and damping ratios as the optimum objectives, the method conducts optimum calculations on the dynamic parameters of the guideway joint using the Amijo rule based Quasi-Newton BFGS algorithm in a Matlab-Ansys integrated environment. Optimized results show that the method proposed is of good quality of convergence, and their precision meets the requirements of engineering applications.