A workpiece-based method to identify the main geometric errors for an Ultra-precision turning machine tool

Ultra-precision machine tool has been widely applied to the field of aerospace, biomedicine and electronic communications, and is one of the key factors to promote the continuous development of electronic information technology, process technology and various kinds of advanced manufacturing technologies. Researchers paid more and more attention to the improvement of machining accuracy. The geometric errors of machine tool will cause the actual tool trajectory deviated from the ideal one, which leads to the machining error to reduce machining accuracy and plays ultimately a significant and direct influence on the machined component. Due to this issue, a workpiecebased method is proposed to identify the main geometric errors for an ultra-precision turning machine tool. The volumetric error modeling for a 3-axis diamond turning machine is established by multi-body system (MBS), and the variancebased global sensitivity analysis (GSA) is employed to identify the error parameters that significantly affect the model's output and to assess its quality factor. Workpieces were designed to figure out the main geometric errors according to the results of GSA. The significance of the present study is to provide a new method to directly estimate the influence of main geometric errors on the machining accuracy based on the measurement result of the machined component.