Multi-Axis Dimensional Error Modeling and Sensitivity Analysis in a CNC Machining Center

To improve machining accuracy, a multi-axis linkage dimensional error calculation model was established based on multi-body system theory and validated by the experiment. A comprehensive sensitivity analysis for a CNC machining center was conducted. The results reveal that multi-axis machining errors depend not only on the machine’s structural dimensions but also dynamically vary with the axes’ motion positions. Specifically, X-axis machining errors are most sensitive to δx(z), δx(y), δx(x), εy(y). Y-axis machining error is more sensitive to δy(z), δy(y), and δy(x). Z-axis machining error is more sensitive to δz(z), δz(y), and δz(x). The practical implications of these findings identify the specific dimensional errors that most significantly impact overall accuracy, providing a targeted theoretical reference to prioritize the compensation of key dimensional errors and effectively enhance machine tool precision.