Abstract: Ontology is widely used as an important means for describing product design knowledge. However, most ontology expressions still cannot effectively model product design. Port, as the location of intended interaction between the component and its environment, plays a critical role for component concept formation. It constitutes the interface of a component and defines its boundary. The definition of port-based ontology is firstly given and port types are classified as mechanical port, electrical port, information port and so on. Functional ontology semantics and primitive functional concepts of port are presented, and four kinds of connected relationships are obtained by estimating the similarity between two primitive concepts, that is, causal connection, equivalent connection, opposite connection and combined connection, and the connector types are presented to carry out the decision of port compatibility. The attributes and taxonomies of port are studied to acquire port ontology knowledge, build the process of conceptual design, and present port-based three view models which contain functional view, behavioral view and configuration view. Port ontology modeling language is described in order to build a framework of port ontology, and a case study of reversal rinse device is illustrated to show its application.

Key words: Compatibility, Conceptual design, Connector, Functional ontology, Port-based ontology