基于柔度耦合子结构法的主轴-卡盘与工件结合面参数辨识

Parametric Identification of Spindle-chuck and Workpiece Interfaces Based on RCSA

车削加工系统振动特性参数的获得对加工精度和加工质量的控制、加工参数选择有重要意义,主轴-卡盘子结构和工件子结构结合面参数难以精确测量和解析计算。基于柔度耦合子结构法(RCSA)建立车床主轴-卡盘-工件系统工件自由端频响函数的预测模型,用遗传算法对加工系统锤击激励模态实验频响函数与其频响函数模型预报值的相对误差进行目标函数寻优,辨识出子结构间的结合面参数。结果表明:预测模型与锤击激励模态实验获得加工系统工件自由端频响函数有较好的一致性,该辨识方法可应用于车削工件表面加工精度和加工质量的控制。

It is important to obtain the vibration characteristic parameters of the turning processing system for the control of the processing effect, machining quality and the selection of machining parameters. It is difficult to accurately measure and calculate the parameters between the spindle-chuck and the workpiece interfaces. Reeeptance coupling substructure analysis （RCSA） method was used to establish the frequency response functions （FRFs） prediction model of workpieee tip for lathe spindle-chuck-workpiece system. The parameters between the substructures interfaces was identified by using genetic algorithm （GA） optimizing the objective function of the FRFs relative error which between impact testing and predicted of the machining system. The results show that the FRFs of machi- ning system by predicted agree well with the measured ones. The parametric identification method can be used to control the machining precision and quality of the turning workpiece surface.