Dynamics and cutting stability of dynamically loaded worktable subjected to elastic supports

This paper investigated the dynamic characteristics and the cutting stability of a dynamically loaded worktable on elastic supports in a surface grinder. The operation of worktables is usually dynamically loaded in various positions, which results in a complex system of governing equations. In this study, the assumptions of elastic and rigid body modes of a free-free beam were specified in analyzing the worktable. By combining the Lagrange energy method with the technique of assumed mode expansion, the system of equations was developed. The absolute value of the maximum negative real part of the overall dynamic compliance (MNRPODC) and the limiting chip width were used as the performance indicators to evaluate the structural characteristics of the worktable during simulated machining. The 3D stability lobe diagram was then computed. The cutting stability was verified by comparing the results obtained in time-domain analysis with the lobe diagram. The procedure presented in this study to improve the dynamics performance of a surface grinder can also be implemented in a similar fashion for many other machine tool applications.