In conceptual design, a designer decomposes a required function into sub-functions, so-called functional decomposition, using a kind of functional knowledge representing achievement relations among functions. Aimin at systematization of such functional knowledge, we proposed ontologies that guide conceptualization of artifacts from the functional point of view. This paper discusses its systematic description based on the functional ontologies. Firstly, we propose a new concept named “way of achievement” as a key concept for its systematization. Categorization of typical representations of the knowledge and organization as is-a hierarchies are also discussed. Such concept, categorization, and functional ontologies make the functional knowledge consistent and applicable to other domains. Next, the implementation of the functional ontologies and their utility on description of the knowledge are shown. Lastly, we discuss development of a knowledge-based system to help human designers redesign an existin artifact. The ontology of functional concepts and the systematic description of functional knowledge enable the supporting system to show designers a wide range of alternative ways and then to facilitate innovative redesign.
