Identification of integrated geometric errors of rotary axis and setup position errors for 5-axis machine tools based on machining test

Abstract

As a fundamental error source, geometric errors of 5-axis machine tools have a negative influence on a machine tool’s motion accuracy. Large numbers of efficient and robust geometric error measurement and compensation methods have been developed by existing researches to improve the performance of the machine tools during the automatic machining of the workpiece. However, influence of the geometric errors on workpiece clamping is hard to measure and evaluate in most of the clamping processes since manual operations are involved. It is important to identify both geometric errors and setup position errors to control the entire machining process, standing from the perspective of a manufacturer. In this study, a position-dependent geometric error and setup position error identification method is investigated based on machining test. A kinematic model for a 5-axis machine tool with tilting rotary table is constructed while considering both geometric errors of the two rotary axes and setup position errors. Machining patterns and calculation algorithm are designed to analytically calibrate these errors. Experimental demonstration is conducted to validate the feasibility of the proposed measurement method.