New device for rapid measurement of machine tool geometric errors

Control systems of modern machine tools are equipped with a number of functions for volumetric accuracy enhancement. These functions can compensate for all the geometric errors of the axes, which are characterized by 21 errors for a 3-axis machine tool. Compensation data are stored in compensation tables and the control system calculates actual compensation based on these tables and actual machine tool position. Geometric errors are measured within the machine tool maintenance plan and it presents a time-consuming process. Measurement is mainly based on interferometric devices, where the precise setup of laser source and detector is challenging. This article introduces an original system for automatic interferometer set up to speed up the measurement of geometric errors. The system is designed for the interferometer Renishaw XM-60, which simultaneously measures all 6 degrees of freedom. The developed control software identifies interferometer position and transforms the measured data into a machine coordinate system. Numerical simulation verified the proposed solution.