Abstract
Functionality is one of the key concepts of knowledge about artifacts. Functional knowledge shows a part of designer's intention (so-called design rationale), and thus its sharing among engineers plays a crucial role in team-activities in engineering practice. Aiming at promoting engineering knowledge management, we have developed an ontological modeling framework of functional knowledge, which includes an ontology of device and function and a controlled vocabulary. This framework has been successfully deployed in a manufacturing company in daily engineering activities. In the first part of this paper, we discuss some ontological issues concerning the functionality of artifacts, and redefine the notion of function as a role. In the second part, we discuss some lessons learned in the actual deployment of this framework and two extensions based on such experience. One extension is a lexical layer for functional terms intended to help engineers select appropriate functional concepts and to facilitate the use of domain-specific terms familiar to them. The other extension is the establishment of ontological modeling guidelines, which help engineers commit to the relevant ontologies and describe models compliant with them.