A proposed structure for a rule-based description of parametric forms

Abstract

Much work has been carried out on the creation of protocols for the exchange of data between CAD systems, but very little on the transfer of knowledge. The knowledge behind the development of a product is vital if modifications and adaptations are to be made within a concurrent development environment. Current CAD systems only contain a limited level of product knowledge through user-defined parametric structures. It is the underlying relationships in these programs that need to be communicated between systems, rather than the form of their individual programming languages. A generic structure is proposed that is able to handle both the current level of parametric programming and is suited to the resolution of conflict through the use of constraint modelling procedures. The structure of a parametric description is described and decomposed into its fundamental components. These components are then re-formed within a truth maintenance structure to allow a transfer protocol to be created. The derived protocol structure is then demonstrated on a number of simple examples.