Automated Tradeoff Analysis of Cost Versus Machinability for Design Feedback

Abstract

As computer aided design (CAD) tools become more sophisticated, engineers are able to more easily create complex part geometries with minimal mass given strength and stiffness requirements. However, these complex part geometries can be difficult to subtractively manufacture, which consequently increases manufacturing cost and production time. This paper presents a method for use during the embodiment design process to automatically evaluate a given part’s machinability and to provide visual geometric additions that decrease manufacturing cost while maintaining the part’s strength and stiffness requirements. Dividing a single part into multiple subparts—joined together after being machined—offers additional possibilities for cost reduction and machinability improvements by utilizing smaller stock material that requires fewer machining operations. Evaluating and culling candidates based on two objectives (added volume and cost) provide the design engineer with a set of Pareto-optimal solutions that show where material can be added to reduce manufacturing costs. These methods’ capability and utility are demonstrated through analyses of five example parts.