Sensitivity Analysis of Geometric Accuracy of Three-coordinate CNC Machine Tools Based on EFAST Method
The geometric errors of machine tools is one of the main factors affecting the machining accuracy of ma-chine tools.This paper focuses on the geometric errors modeling of machine tools,the sensitivity analysis of geometric accu-racy,and the selection of key geometric errors.Based on the theory of multi-body system and homogeneous coordinate trans-formation,the geometric errors model of three-coordinate CNC machine tools is established,and the spatial position error ex-pression of the machine tools is solved.The geometric errors of the three-coordinate CNC machine tools are measured with Renishaw XL-80 laser interferometer,and the measurement results are introduced into the nine line errors identification model to identify 21 geometric errors of the three-coordinate CNC machine tool.By using the Extended Fourier Amplitude Sensitivity Test(EFAST)in the Simlab software,the sensitivity analysis of the geometric errors of the three-coordinate CNC machine tools is carried out,and the key geometric errors affecting the accuracy of the three-coordinate CNC machine tools are screened out.In addition,based on the key geometric errors,a simplified geometric errors model of the three-coordinate CNC machine tools is established and compared with the geometric errors model of the three-coordinate CNC machine tools.The analysis results show that the method can reasonably and economically improve the machining accuracy and geometric errors compensation of three-coordinate CNC machine tools.
machine tools geometry errorthree-coordinate CNC machine toolsensitivitylaser interferometerspatial position error
万方数据
维普
