Creating Stability Lobe Diagrams during Milling

Motorized spindles are in common use in high-speed milling. The dynamic behavior of the spindle depends on the actual number of revolutions and the temperature. The performance of the spindle during milling, particularly, the behavior concerning chatter, is crucially affected by the speed dependent dynamic behavior of the mechanical system. This paper presents the reasons for the speed-sensitive stiffness and the shifting stability lobes. A new method of measuring and calculating the dynamic behavior during milling by means of sub-space-state-space-identification methods is introduced. Finally, the computed stability lobe diagrams are compared with experimentally determined stability lobe diagrams.