Quality Assured Setup Planning Based on the Stream-of-Variation Model for Multistage Machining Processes

Setup planning is a set of activities used to arrange manufacturing features into an appropriate sequence for processing. It has significant impacts on the product quality, which is often measured in terms of dimensional variation in the Key Product Characteristics (KPC). Current approaches to setup planning are experience-based and tend to be conservative by selecting unnecessarily precise machines and fixtures to ensure final product quality. This is especially true in multistage machining processes (MMP’s) because it has been difficult to predict the variation propagation and its impact on the KPC quality of final product. In this paper, a new methodology is proposed to realize cost-effective, quality assured setup planning for MMP’s. Setup planning is formulated as an optimization problem based on quantitative evaluation of variation propagations. The optimal setup plan minimizes the cost related to process precision (CRPP) and satisfies the quality specifications. The proposed approach can significantly improve the effectiveness as well as the efficiency of the setup planning for MMP’s.