One of the most important, but difficult dynamic problem to sustain high productivity and quality in machining processes is to avoid or suppress the chatter. In order to do so, it is believed by many authors that the machining process, which consists of machine tool structure and cutting process, should be analyzed deterministically as a closed loop. The conventional analysis, however, was not only unrealistic due to so many assumptions, but also required tremendous experimental and analytical procedures.
Considering that the inherent characteristics of a machining process are stochastic, a stochastic modeling methodology, so called Dynamic Data System (DDS), is applied to the analysis of vibration signals measured under actual working conditions. It is shown that the DDS methodology, in comparison with spectral analysis, is more successfully applied to the stability analysis of a turning machine.