Automated Tradeoff Analysis of Cost Versus Machinability for Design Feedback

Abstract

Abstract As 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 independent of CAD kernels for use early in the 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. Using tessellated and voxelized representations of a part geometry, potential machining orientations are identified and selectively combined to form a set of candidate solutions. The resulting part geometry for each candidate is determined by intersecting the machinable geometries for each individual machine setup, and may have some amount of added volume over the as-designed part. Manufacturing costs for each candidate are estimated based on the volume to be machined and number of required machining setups. Evaluating and culling candidates based on these two objectives (added volume and cost) provides the design engineer with a set of Pareto-optimal solutions that show where material can be added to reduce manufacturing costs. The method is implemented and is tested on three example parts to demonstrate its capability and utility.