Contour error compensation strategy for multi-axis machining by trajectory error modeling

To improve the machining precision of multi-axis machine tools, diminish its contour error caused by various factors of the transmission mechanism, such as mass, rigidity, damp and friction, and aiming at the difficulty of parameter identification in the cross-coupled control method and the induced system instability, a novel error modeling and compensation strategy for multi-axis machine tools is proposed. The contour error model is established by measuring several contour errors of typical trajectory, and the contour error can be calculated and compensated by the error model during machining process. The new compensation strategy is implemented on a x, y table, which shows that the new approach enables to significantly reduce the contour error of circle and trajectory with continual curvature and improve the multi-axis machining precision, especially for high speed machining.