Cutting process stability of a boring bar with active dynamic absorber

Active vibration control has been considered in the past as a viable means of controlling machine tool chatter in the boring bar. Theoretically, it has been shown that the amplitude of vibrations of the machine tool can be substantially reduced using such an active control system. This paper looks into the cutting process stability of a boring bar equipped with an active vibration control device. An equivalent lumped mass model of the boring bar is considered. A cutting process model that considers the dynamic variation of shear and friction angle responsible for the self-excited vibration during machine tool chatter is considered. The model also considers the regeneration effect during the cutting process. Stability charts have been obtained in the form of maximum allowable width of cut as a function of cutting speed. A comparison of the stability boundaries of the boring bar with no control, with passive dynamic absorber and with active dynamic absorber is made. A substantial increase in the region of stable operation of the boring bar with active dynamic absorber is observed.