数控机床旋转轴几何误差测量与辨识研究

辨识机床旋转轴的几何误差是提高机床加工性能的关键。然而在测量过程中,摆放误差对测量结果的影响不可避免。过多的拆卸与摆放不同的位置进行误差测量会导致较多的摆放误差引入到测量结果致使辨识的误差结果不精确。为了减少上述的影响,基于多体系统理论通过球杆仪测量方程提出一种测量方法,该方法仅仅通过球杆仪两个位置的移动测量便可辨识旋转轴与位置有关的6项几何误差,降低了由于过多拆卸和摆放球杆仪造成摆放误差对测量结果的影响。最后以RTTTR型五轴机床为例,通过MATLAB程序仿真验证了该方法的可行性。程序仿真表明,该方法在精密机床旋转轴几何误差测量的精度检测中具有一定的应用前景。

Research on Measurement and Identification of Geometric Errors of CNC Machine Tool Rotary Axis

Identification of geometric errors of rotary axis is a key step to improve the accuracy of machine tools. However, during the procedure of measurement, installation errors of instruments are inevitable. Redundant measurement procedure to identify geometric errors causes the inaccuracy of identified result because of the installation errors. In order to decrease the influence of installation errors, a novel measurement method was proposed based on multi-body system theory and equation of double ballbar. The method could identify position dependent errors of rotary table merely through two measurement location, which decreased the influence of installation errors. Finally, simulations were conducted to validate the correctness and effectiveness of proposed method on RTTTR type five-axis machine tool. The results indicate that the identification method proposed is applicable for the precision detection in high precision machine tools.