Three-axis milling machine tools are widely used in manufacturing enterprises, and they have enormous potential demands for remanufacturing to improve their performance. During remanufacturing a three-axis milling machine tool, the structure needs to be reconstructed, so it is necessary to identify sensitive geometric errors of the remanufactured machine tool. In the traditional sensitive geometric error identification method, complex error modeling and analysis must be conducted. Therefore, professional knowledge is required, and the process of the identification is cumbersome. This paper focused on the quick identification of sensitive geometric errors for remanufacturing of three-axis milling machine tools. Firstly, sensitive geometric errors of a three-axis milling machine tool were identified based on the multi-body system theory and partial differential method. Then, mapping laws between the sensitive geometric errors and the machine tool structure were firstly presented. According to the proposed mapping laws, the sensitive geometric errors can be identified quickly and easily without complex error modeling and analysis. Finally, the simulation and experiment show that the straightness error of milling is improved up to 0.007 mm by compensating the sensitive geometric errors identified by the proposed mapping laws. The table lookup method based on the mapping laws can quickly identify the sensitive geometric errors of three-axis milling machine tools, which is beneficial for the efficiency and precision of remanufacturing of machine tools.

This paper focuses on the application of electrical machines in public transportation and investigates the potential benefits of auxiliary slot design on this kind of high-speed low torque machine. A preliminary surrogate-based optimization is conducted to the shape of auxiliary slots on the stator for minimizing its cogging torque ripple while maintaining its Total Harmonic Distortion (THD) at an acceptable level. The results show the optimization achieves its best performance while the edges of the auxiliary slot are parallel to the edges of the stator teeth, which could reflect a deeper resonance among the geometries of the stator magnetic field.