多轴数控机床转台几何误差辨识新方法  

New geometric error identification of turntable for multi-axis machine tools

作　　者：冯刚[1] 付国强[2] 孙磊[2] 傅建中[2] 

机构地区：[1] 浙江工业职业技术学院 浙江绍兴312000 [2] 浙江大学机械工程学院 浙江杭州310027

出　　处：《浙江大学学报（工学版）》2015年第11期2083-2091,共9页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(51175461);浙江省自然科学基金资助项目(Y14E050069);中央高校基本科研业务费专项资金资助项目(2014QNA4004)

摘　　要：为了系统地辨识多轴数控机床转台的10项几何误差,提出一种基于球杆仪测量的转台几何误差六步骤测量法.根据球杆仪方向向量并结合六步骤中各个步骤球杆仪位置得到球杆仪读数与转台几何误差项之间的模型.根据几何误差项的性质,辨识得到包括垂直度误差和位置误差的10项几何误差.仿真结果验证六步骤测量法的正确性.为了提高辨识精度,分析球杆仪安装误差对各个步骤中球杆仪读数的影响,采用最小二乘法拟合得到消除安装误差后的球杆仪读数.采用六步骤测量法辨识SmartCNC500五轴机床转台几何误差,对这些误差进行补偿后比较补偿前后球杆仪读数,补偿后球杆仪读数误差,误差降低了56%~61.9%,结果表明六步骤测量法精度高,只需转台旋转,且运动易实现,球杆仪安装方便.The geometric error identification approach based on ballbar measurement, six-step measure- ment, was proposed in order to obtain the ten geometric errors of turntable for multi-axis machine tools systematically. Models between ballbar readings and geometric errors of turntable were obtained based on the direction vector of ballbar and the position of ballbar in each step of the six step measurement. Accord- ing to the property of geometric errors, all the ten geometric errors of turntable were identified including squareness errors and offset errors. The corresponding simulation testified that the six-step measurement was appropriate. To further improve the accuracy of six-step measurement, the influence of the set-up er- rors of ballbar was analyzed. The least square method was used to fit the ballbar readings without the set- up errors. The six-step measurement was applied to SmartCNC500 five-axis machine tool to identify the geometric errors of turntable. The obtained geometric errors were also compensated. The ballbar readings with and without the compensation of geometric errors of turntable were compared. The ballbar readings with compensation decreased about 56% to 61.9%. The results show that six-step measurement has high precision and only needs single rotation of turntable. Meanwhile, it＇s convenient to realize the motion of ballbar with six-step measurement, and the installation of ballbar is easy.

关 键 词：六步骤测量法 球杆仪 转台 几何误差 安装误差 

分 类 号：TH161[机械工程—机械制造及自动化]