A non-contact calibration method for cutter runout with spindle speed dependent effect and analysis of its influence on milling process

Abstract

The Cutter runout in traditional studies about milling mechanics and dynamics are always assumed as a constant value. Actually, the dynamic characteristics and vibration response of spindle system will change under different spindle speeds, which would result in a spindle speed dependent effect for cutter runout. A non-contact calibration method for cutter runout with consideration of spindle speed dependent effect is proposed in the paper, and the influence of cutter runout on milling mechanics and dynamics is further analyzed. Based on the measured relative variation of tooth by the eddy current sensor measurement system, a numerical optimization method for identifying cutter runout parameters is presented. The main advantage of the method is simple and convenient, especially for studying the cutter runout under different spindle speeds. Then, the paper gives out an instantaneous uncut chip thickness model during cutter/workpiece engagement with runout effect, and puts forward an enhanced SDM for milling stability prediction. Theoretical and experimental results show that milling force, stability and SLE prediction considering the cutter runout with spindle speed dependent effect have a higher prediction accuracy compared with other previous methods. Lastly, the studies analyze the influence of cutter runout on milling force, milling stability and SLE, and the results indicate that cutter runout can improve the milling stability, but deteriorate the milling force excitation characteristics and SLE.