Abstract:In order to promote the movement precision of CNC machine tool translational axis, thereby to meet the requirements of modern CNC system for its high precision, the in depth research was developed that aimed at space geometric error of CNC machine tool translational axis. A convenient method was proposed that could effectively identify the space geometric error of translational axis, and established the translational axis space geometric error identification model which based on the homogeneous coordinate transformation principle. According to the characteristics of CNC machine tool translational axis of positioning error, the incremental principle of error compensation was proposed which could realize effective compensation, and the corresponding error compensation model was established. After verified, the proposed translational axis of error identification method and incremental error compensation principle are not only correct in theory, but also can significantly improve the positioning precision of the machine tool translational axis.