Research on detection of the linkage performance for five-axis CNC machine tools based on RTCP trajectories combination

The five-axis machine tool has been extensively employed in complex curved surface machining area. The linkage performance of the machine tool is one of the key origins of the machining accuracy. An accuracy measurement based on RTCP (rotation tool center point) is an effective means for multi-axes motion synchronously linkage performance detection. In order to demonstrate the linkage performance more completely, an RTCP trajectory description method is presented, and some trajectories which take account of curvature and speed changes are proposed in this paper. The trajectory sensitivity analysis is applied to examine the sensitivity of RTCP measuring trajectories in mismatch parameters of the five-axis machine tool. Through comparative analysis, some RTCP measuring trajectories are more sensitive to certain error parameters than others. Therefore, the corresponding RTCP measuring trajectories are necessary for various linkage performances detection of the five-axis machine tool. For this purpose, RTCP measuring trajectory is optimized based on sensitivity analysis result. Finally, linkage performance detection experiments based on RTCP are conducted, and the tool tip errors vary for the different linkage performance and different RTCP trajectories, which is consistent with trajectory sensitivity analysis results. These results indicate that the corresponding RTCP measuring trajectories are necessary for various linkage performance detections. Therefore, the RTCP trajectory that is more favourable to detection could be put forward according to the requirements of the five-axis machine tool. Furthermore, series of RTCP trajectories can be combined to exhibit the linkage performance of five-axis machine tools more comprehensively.