Three Conceptual Levels for the Artifacts Design

In this paper we present a theoretical framework for the formalization of design methodologies of artifacts, in which we distinguish three levels: the design strategies level, the artifacts representation level, and the level of graphics systems for 3D rendering. This work proposes both a formal apparatus for the definition of design strategies, considered as processes operating on representations of artefacts, and provides a methodological contribution to the building of knowledge-based aid design systems. The key idea of the paper is that, independently of the design type, it is essential to separate the level of design strategy from that of artifact representation and to connect them through appropriate translation rules. The strategy level is a "meta"-level with respect to the representation level. Therefore when we formalize a strategy, we must represent it through a language of greater order than the one used in formalizing the artifact representation. In this paper we present a formalization of some typical design strategies classes for every-day artifact in which an artifact is represented as a class of a formal ontology. Though the methodological and formal apparatus presented has been defined for the generative design operating method, we think that the concepts here exposed apply also to other architectural design approaches.