Simulation of HSM: accurate measurement of speed dependent cutting force coefficients and dynamics for chatter detection

Prediction of chatter is a key factor for improving machining processes, especially for high speed milling (HSM) where wide stable zones at high depth of cut can be exploited. The ever increasing use of such process is pushing further the development of advanced techniques to predict chatter. However these are limited by the reliability of input data such as cutting force coefficients and tool-tip dynamics. Both are influenced by spindle speed: cutting mechanics could change at different cutting speeds affecting the force coefficients and spindle dynamic behavior could be different changing rpm. This paper presents a novel experimental approach called Spindle Speed Ramp-up (SSR) to efficiently estimate speed dependent cutting force coefficients and to obtain the influence of the rotational speed on spindle dynamics for chatter detection, particularly useful in HSM. SSR test is time efficient and enables the operator to evaluate experimentally stable and unstable regions map of the setup with a few tests.