Dynamic reaction of machine tools to transient cutting conditions

Abstract Transient machining conditions often occur during the milling process, especially when complex toolpath layouts are deployed. Although modern CAM-aided toolpath generation algorithms aim at keeping the cutter engagement conditions as constant as possible and avoid sudden changes, this can not always be ensured. These transients are accompanied by temporary peak excursions in cutting forces and changing dynamic content of the excitation forces. This may have the potential to excite unwanted vibrations in the machining process and even may initiate chatter. Using a virtual process simulation environment it is possible to predict resultant dynamic forces along a complete NC tool path with high time and angular resolution and gain insights into the dynamics of transient events during machining operations. This simulation environment has the capability to use an analytical cutting force model, which spares extensive testing and parameter identification beforehand. Besides, well known empirical cutting formulations can be used as well. The results of the dynamic force prediction is compared against experimental results for different toolpath layouts and the dynamic behavior of the machine tool under cutting conditions will be discussed.