Evaluation of Synchronous Motion in Five-axis Machining Centers With a Tilting Rotary Table

This paper proposes a new method for evaluating the synchronous inaccuracy of a translational axis and a rotational axis in five-axis controlled machining centers with a tilting rotary table. A circular trajectory whose shape is easy to evaluate the specific features is adopted for measuring the circular path described by the two axes. The influence of inaccurate synchronization on the circular path was simulated by changing the distance between the centers of the rotary table and the circular path, the radius of the circular path and the feed speed. Measurement conditions were determined based on the simulation results, and then ball bar measurements and machining experiments were conducted. From the simulation and experimental results, it is confirmed that the proposed method can be used for evaluating the inaccurate synchronization of a translational axis and a rotational axis. However, careful alignment of the center of the rotational axis and the machine coordinate origin is important for evaluating the synchronous accuracy. The ratio of the distance between both centers of the rotational axis and the circular path to the radius provides useful information for the evaluation.