Body diagonal error measurement and evaluation of a multiaxis machine tool using a multibeam laser interferometer

Abstract

To comprehensively evaluate the accuracy and performance of machine tools, in this paper, a novel measuring method for the body diagonal error of a machine tool using a multibeam laser interferometer as the measuring instrument is proposed. On this basis, a three-dimensional evaluation method for the body diagonal error of a machine tool is proposed. First, a method of measuring the body diagonal error of a machine tool by using a multibeam laser interferometer is proposed. Six errors for the body diagonal of a machine tool can be measured simultaneously, including three position deviations and three angle errors. The mathematical model of the relationship between the measured data and the volumetric error is established. Second, a new evaluation method for the body diagonal error is presented that takes the position deviation and attitude error into consideration. The advantage of this evaluation method is that it fills in the blanks in the evaluation method for the body diagonal error. The method can also be applied to the evaluation of linear axis error. Finally, the proposed measurement method is applied to a vertical three-axis machining centre, and the experimental results show that this measuring method is quite convenient and effective for measuring the body diagonal error of a machine tool. The proposed method is used to evaluate the body diagonal error from measurement data. The results show that the positioning error of the machine tool is 49.37 ??m; the repeatability of the positioning error is 36.85 ??m; and the angle errors are ??????22.47 ??m/m, ??????70.9 ??m/m and 29.7 ??m/m. The traditional method (ISO230-6) is used to evaluate the body diagonal error from measurement data. The results show that the positioning error of the machine tool is 49.4 ??m. Compared with the traditional method, the information from the proposed evaluation method is more abundant, and the evaluation method is systematic and universal.