应用激光跟踪仪的数控机床空间精度检测方法  

Measurement method of volumetric accuracy of CNC machine tools using laser tracker

作　　者：韩林 肖杰 何韬 石纯标 袁明记 HAN Lin;XIAO Jie;HE Tao;SHI Chunbiao;YUAN Mingji(China Academy of Engineering Physics,Institute of Machinery Manufacturing Technology,Mianyang 621900,China;National Machine Tool Production Quality Inspection and Testing Center(Sichuan),Chengdu 610200,China)

机构地区：[1]中国工程物理研究院机械制造工艺研究所,四川绵阳621900 [2]国家机床产品质量检验检测中心(四川),四川成都610200

出　　处：《中国测试》2022年第12期52-59,共8页China Measurement & Test

基　　金：国防科工局技术基础科研项目(J0067-1922-FJC);四川省重大科技专项项目(2020ZDZX0003)。

摘　　要：为实现数控机床空间精度快速、高精度测量,提出一种应用激光跟踪仪的数控机床空间精度快速求解方法。首先,分析激光跟踪仪测量数控机床空间精度的基本原理,建立激光跟踪仪测量数控机床空间精度的数学模型;其次,推导测量方程的线性化矩阵形式,基于秩亏自由网平差约束条件,实现数控机床空间精度的快速求解;并考虑激光跟踪仪测长误差引起的不确定度来源,基于蒙特卡洛方法进行测量不确定度评定;最后,在机床运动传递链为工件-Y轴-X轴-Z轴-刀具型式的三轴数控机床上开展数控机床空间精度测量与不确定度评定和验证试验。结果表明:该三轴数控机床空间精度为31.6μm,标准不确定度为10.2μm;与激光干涉仪定位偏差检测结果相比X、Y和Z轴线最大相差6.4μm,测量不确定度与多次重复测量结果标准差相比最大相差2.1μm,验证空间精度测量和不确定度评定方法的有效性。To implement the rapid and high-accuracy measurement of volumetric accuracy of CNC machine tools, a novel measurement method of volumetric accuracy of CNC machine tool using laser tracker is proposed. Firstly, the measurement principle of volumetric accuracy of CNC machine tools using a single laser tracker is analyzed, and the mathematical model is established. Then, the linearization matrix of the measurement equations is derived. Based on the constraints of rank-deficiency free network adjustment, the volumetric accuracy of CNC machine tool is determined with high efficiency. Considering the uncertainty caused by the length measurement error of laser tracker, the Monte Carlo method is adopted to evaluate the measurement uncertainty of volumetric accuracy. Finally, the volumetric accuracy measurement and uncertainty evaluation and verification experiments are carried out on a three-axis CNC machine tool of which the kinematic chain is Workpiece-Y axis-X axis-Z axis-Tool, and the comparison experiments with the positioning deviation measured by laser interferometer and the repeated measurement results are implemented.The experimental results show that the volumetric accuracy of the CNC machine tool is 31.6 μm and the standard uncertainty is 10.2 μm. The maximum difference of positioning deviation of X, Y and Z axes is 6.4 μm compared with the results measured by laser interferometer. And the maximum difference between the measurement uncertainty and the standard deviation of repeated measurement results is 2.1 μm. The comparison experiments verify the effectiveness of the volumetric accuracy measurement and measurement uncertainty evaluation method.

关 键 词：激光跟踪仪 机床空间精度 秩亏自由网平差 蒙特卡洛方法 测量不确定度 

分 类 号：TH161[机械工程—机械制造及自动化] TB9[一般工业技术—计量学]