Optimal passive vibration control of cutting process stability in milling

Abstract

The paper proposes a design concept for an optimal passive dynamic absorber in the milling process. An investigation and analysis into the characteristics of, and interaction between, forced vibration and linear chatter in milling has been carried out by use of a two-degree-of-freedom structural model simulation. A dynamic absorber mass is then connected to the main system through passive elements (spring and damper). Optimization procedures to determine the optimum values of spring and damping coefficients for a specific mass ratio have been developed by employing the ADS optimization package. A theoretical approach for the prediction of machine tool chatter in milling including dynamic cutting forces permits calculation of borderlines of stability for a structure model with an optimal absorber. Compared with the limit of stability under no control, the stable range under optimal passive control has been improved over one hundred percent. Transient responses can also be obtained from numerical integration of the system's equation of motion in the state variable representation based on the fourth-order Runge-Kutta method. The theoretical predictions can be verified by the results of numerical simulation of transient response. © 1991.