Abstract
A vibration due to the interaction of feed drive systems with the machine tool structure has a great influence on the relative position between tool and workpiece. In this study, a state space equation model of NC machine tool which considers the vibration of the machine tool structure is proposed. This model also considers the torsion vibration of the bed, friction and vibration of feed drive mechanism of each axis based on analyzed vibration mode of the machine. Procedure of parameter determination is also proposed. Frequency response and vibration mode, feedback position, table position and the relative position between table and head are simulated and compared with the actual ones. As the results, it is confirmed that the proposed model can adequately predict the vibration mode and circular trajectories.
