Integration of CAD, CAPP and Process Modeling Using XML Technologies

Abstract

Integration of CAD (Computer Aided Design), CAPP (Computer Aided Process Planning) and Process Modeling activities plays a vital role in enabling concurrent product and process design. Typically each of these functions is performed in its own dedicated software environment. The integration will require interfacing several disconnected processes and software components built in different languages, and platforms. This paper presents an integration methodology, validated using a case study, in which a steering housing was analyzed and its process planning and design tasks were integrated using several software tools. The first integration task was to generate a feature based CAD model (in Unigraphics) and map these design features to a set of manufacturing features. Feature based design was performed using the Horizontal Modeling™ approach developed at Delphi. Features developed using this approach were then mapped to manufacturing features using APPS, a software tool developed at Delphi Dynamics and Propulsion Innovation Center. This task involved interrogation of the geometric CAD model to generate geometric and tolerance information and represent them in a format suitable for feature-based process planning. The second task of integration is generation of feasible “production-intent” process plans. This task is performed using APPS and IMPlanner process planner, a knowledge based software tool developed at Ohio University. The third and final task of integration is automated generation of in-process CAD models. This task involved the integration of Delphi process design techniques to generate CAD models (in Unigraphics) to represent the component at each stage of the manufacturing process. Evaluation of these steps through the case study has identified the strengths and weaknesses of the proposed integration methodology, which is reported in this paper.