Investigation on the dynamic behavior of machine tool with respect to different worktable feed rates

With the rapid application of high speed machining, the feed rate of moving parts has an important influence on the dynamics of high speed machine tool. In this paper, a method of modal decoupling of Operational Deflection Shapes (ODS) was proposed to investigate the dynamic behavior of machine tool with respect to different worktable feed rates. Based on this method, the dominant frequencies vibration of the machine tool at different frequencies and its transformation at different worktable feed rates was identified. Finally, a series of empty running experiments were performed under different worktable feed rates. The experimental results show that (i) the change of worktable feed rate will affect the contribution of different modes vibration to the machine tool vibration; (ii) the contribution of a certain mode vibration to the machine tool vibration is different at different worktable feed rates; (iii) with the worktable feed rate increasing, the change rule of dominant frequency vibration participation is from multimode participation to single mode dominant, and then to the multimode participation. This research will provide valuable information for the selection of machine tool operation parameters and the optimization design of machine tool structure.