| Design for Manufacturing (DfM) involves trade-offs between design objectives and manufacturing cost/efficiency. Several measures have been proposed for manufacturability in the literature. However, these measures either lack sound theoretical foundations or are not applicable in the DfM context. This work explores and evaluates these measures and proposes Benefit Cost Analysis (BCA) as the basis for DfM evaluation. The applicability and rationality of benefit cost analysis to DfM is demonstrated and the value functions of the benefit and the cost are chosen as the DfM measure since it makes explicit trade-offs between manufacturing cost and design benefit.; Another objective of this research is to streamline DfM analysis across all manufacturing domains. Towards this goal, the generic steps in DfM analysis are identified and information models of manufacturing features, process, cost and resource are developed. The design of a customizable manufacturability evaluation shell based on this framework is presented. The shell covers several stages of manufacturability analysis (technical, economic) and can perform analyses at different levels of abstraction (qualitative, quantitative). The shell can be customized and expanded by the knowledge engineer and the user. The architecture of the shell is presented and its applications to manufacturability analysis for two domains, sheet metal and machining, are illustrated.; Today's manufacturing knowledge spans a vast spectrum. In this work, different types of manufacturing knowledge have been identified and represented. An information/knowledge infrastructure has been developed as the backbone to integrate other existing tools into the framework. The schemes to validate the knowledge input by the knowledge engineer have also been developed. The database consistency has been addressed and the consistency enforcement module helps the knowledge engineer build the consistent relational model. A statistical inference technique has been used to verify the qualitative heuristic knowledge using quantitative analysis results. |
