Design concurrent calculation in a CAD-system environment

This paper describes CAD-based approaches to design-concurrent calculation in mechanical design. The first section presents a cost information system that supports cost estimating grounding on conventional 2D CAD-drawings. The method of feature identification is used to extract cost relevant information out of the drawing. Enhanced by some additionally supplied information this data is then processed by a rule-based program. The calculation results are visualized directly in the CAD-system. Due to the total CAD integration, the designer must never leave his familiar CAD environment. During all the necessary steps the designer can stay within the CAD-system he is familiar with. Currently the system is going to be implemented as a prototypical version with a gear manufacturing company. Starting from the experience gathered with the cost information system above, the second section describes a feature-based modeling approach. On the one hand, this method allows a designer work with form features as well as functional features which might be hypothesized to be close to the cognitive units in his/her mind. On the other hand, all information necessary for the cost calculation, i.e., a feature database, evolves simultaneously to designing the geometry. A teaching-module enables the designer to create new feature classes interactively in the CAD-system. After an automatic anticipation of a rough process plan, costs and manufacturability of a part can be checked and results can be graphically visualized. All evaluations are performed by a rule-based program processing the information of the feature database as well as the company-specific engineering database. Thus, this concept supports company-wide data integration efforts.