Detection of Machine Tool Chatter During High Speed Milling

Abstract Issues related to modeling, detecting and controlling machine tool chatter were investigated during high speed milling of aluminum. The growth rate of chatter was measured to determine the time allowed to detect and compensate for chatter. It was found that, depending on the cutting parameters, chatter became fully developed within five to ten rotations of the spindle. During the onset of chatter it was observed that several additional frequencies occurred in the frequency spectrum of the workpiece acceleration. To identify the cause of these additional frequencies a simulation of the forces generated during unstable helical milling was developed. The simulation assumed that the dynamic displacement of the end mill was in a fixed radial direction relative to the end mill. The simulation showed that the combined effect of this radial vibration and tool runout caused excitation at these additional frequencies.