Integrated Error Modeling and Experimental Verification of 2UPR&2RPS-XY Type Five-Axis Hybrid Machine Tool

The accuracy of five-axis hybrid machining equipment is one of the key indicators for evaluating its performance, and error modeling is a prerequisite for achieving accuracy synthesis and kinematic calibration. However, the current error modeling methods mainly focus on the parallel spindle head, while neglecting error sources arising from the series modules. Using such an incomplete error model for accuracy synthesis and kinematic calibration can result in suboptimal accuracy performance of the entire machine. This study focuses on a 2UPR&2RPS-XY type five-axis hybrid machine tool, considers the error influence of the serial sliding gantry module, and proposes a comprehensive error modeling method. Firstly, the error models for the fixed base-tool (2UPR&2RPS parallel spindle head) and fixed base-workpiece (X–Y sliding gantry module) are established using screw theory. Secondly, based on the structural characteristics of the machine tool, an integrated error model is developed. Next, 360 trajectory points are selected from a circular path and substituted into the established error model to obtain the roundness error of the five-axis hybrid machine tool under this trajectory. Finally, experimental validation of the proposed integrated error modeling method is conducted using a double ball bar.