数控机床几何精度综合解析与试验研究

以对机床精度影响较大的几何误差为对象，通过理论与试验相结合，对其进行较深入的研究。基于多体系统理论，综合考虑各轴定位误差、直线度误差以及角度误差等几何误差元的耦合作用，提出一种机床综合误差建模方法，并在机床坐标系下建立三轴数控机床综合误差模型。通过利用激光干涉仪的大量试验得出定位误差、直线度误差以及角度误差曲线，分析证实定位误差相对于直线度误差和角度误差影响更为显著。以此为基础，进一步研究工作空间综合误差在各轴各误差元耦合作用下的分布和演变规律，发现综合误差在某轴向的分量与该轴的定位误差非常接近，给出定位误差是影响综合误差的决定性因素的结论。机床几何精度的分析对于机床精度补偿方法的选取与运用具有理论和实际意义。

Synthetical Analysis and Experimental Study of the Geometric Accuracy of CNC Machine Tools

As the main error source of machine tools, the geometric accuracy is studied theoretically and experimentally. A modeling method of synthesis error is established in the coordinate system of machine tools based on the multi-body system theory, which is applied to a 3-axis CNC machine tool considering the interaction of error terms such as positioning errors, straightness errors and angular errors. By using the laser interferometer system, the positioning errors, straightness errors and angular errors are illustrated by a large number of experiments, which indicates that the positioning errors value is much higher than others. And the distribution and evolution of the synthesis error subjected to the coupling effect of all axes errors are studied in the workspace further. It is found that the synthesis error in the direction of a certain axis is close to its positioning error, which proves that the positioning error is the decisive factor contributing to the synthesis error. The analysis of geometric accuracy is of theoretical and practical significance to error compensation.