Feature-based numerical control program generation from computer-aided design models

The purpose of this research is to develop efficient algorithms for automatically generating complete Numerical Control (NC) programs based on Computer Aided Design (CAD) models of parts. This is a major step toward truly integrating Computer-Aided Design systems and Computer-Aided Manufacturing (CAM) systems.; State-of-the-art in CAD/CAM integration are systems that are capable only of transferring or sharing part data between CAD and CAM, and intensive human interaction is still required to create NC programs. Eliminating this human interaction is the major focus of this research.; A prototype automatic NC programming system has been developed. This system identifies part features and subsequently generate NC programs based on features found. Output programs are processed by CAM systems to generate cutter location data for machine tools. The prototype system recognizes part features and utilizes them as decision making tools.; A surface analysis method is used to identify features from CAD data bases, thereby effectively reducing complex three dimensional geometry into various spatial relationships between two dimensional surfaces. Machinable features are then extracted based on these relationships.; Test cases processed included three dimensional prismatic parts from which NC programs in several different languages were generated. Several electronic housing parts from a local aerospace company were used as test parts. Machining programs were generated and parts were successfully machined on three axis vertical milling machines.; Results from this study indicated that feature-based NC program generation is an effective method to create high quality NC programs for parts that have similar distinctive manufacturing related features.