Abstract: Based on receptance coupling substructure analysis method,a Frequency Response Function (FRF) prediction model of milling tool tip was established.Aiming at the difficulty in obtaining FRF matrix of spindle-tool holder base system through theoretical calculation and experimental approach,a FRF matrix optimal fitting method of tool holder base was proposed based on the combination of experimental modal test and genetic algorithm.By taking the spindle system of a vertical machining center VMC850E as the research object,a predicted FRF of the milling tool tip was performed with the proposed method.Compared with the measured FRF of the tool point,and the result showed that the predicted FRF curve fitted well with the measured FRF curve within the frequency range of 0-4000Hz,and the relative error of natural frequency was under 4.37%.

Key words: milling tool tip point, frequency response function prediction, receptance coupling substructure analysis, genetic algorithms, experimental modal test

摘要： 基于响应耦合子结构分析法建立了铣刀刀尖点的频响函数预测模型,针对其中主轴—刀柄基座系统频响函数矩阵难以理论计算和实验测试的问题,提出了基于实验模态测试与遗传算法寻优相结合的主轴—刀柄基座系统频响函数矩阵的优化拟合方法。以VMC850E型立式加工中心主轴系统为研究对象,基于上述方法对铣刀刀尖点频响函数进行了预测,并与其实测频响函数进行对比。结果表明：刀尖点的预测频响函数曲线与实测频响函数曲线符合较好,预测频响函数的固有频率与实测固有频率在0～4000Hz范围内的相对误差小于4.37%。

关键词: 铣刀刀尖点, 频响函数预测, 响应耦合子结构分析法, 遗传算法, 实验模态测试