Stream of Variation Modeling and Diagnosis of Multi-Station Machining Processes

Product dimensional quality is one of the most important topics in machining processes. However, limited research has been done on the dimensional control and root cause identification methodologies in multi-station machining processes. This paper will study the stream of variation (SOV) problem by developing a new type of model — State Space Model — to describe the dimensional deviation of the multistation machining processes. A process level diagnostic methodology is also developed. A case study is presented to illustrate the developed modeling and diagnostics methodology.