Workpiece-oriented key geometric error identification method for five-axis CNC machine tool

In this manuscript, a workpiece-oriented five-axis CNC machine tool key geometric error identification method is proposed. First, based on the homogeneous transformation method, the spatial error model of the five-axis machine tool is established. Second, taking the convex surface of a typical freeform surface part as an example, the sensitivity analysis of geometric error is conducted, and the key geometric error items are identified. Finally, the machining and key geometric error compensation experiments are conducted on a five-axis CNC machine tool. The results show that the sensitivity coefficient of the key geometric error accounts for approximately 85% of the total error, and the dimensional accuracy of the freeform surface is improved by an average of 24.3% after compensating for the key geometric error, which verifies the correctness and effectiveness of the presented method. This method lays a foundation for the analysis and subsequent compensation of the key geometric errors of complex freeform surfaces in sub-regions, and is of great significance for enhancing the machining precision.