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OntoSTEP: OWL-DL Ontology for STEP



Sylvere Krima, Raphael Barbau, Xenia Fiorentini, Sudarsan Rachuri, sebti foufou, Ram D. Sriram


The Standard for the Exchange of Product model data (STEP) [1] contains product information mainly related to geometry. The modeling language used to develop this standard, EXPRESS, does not have logical formalism that will enable rigorous semantics. In this paper we present an OWL-DL (Web Ontology Language - Description Logic) [2] version of STEP (OntoSTEP) that will allow logic reasoning and inference mechanisms and thus enhancing semantic interoperability. The development of OntoSTEP requires the conversion of EXPRESS schema to OWL-DL, and the classification of EXPRESS instances to OWL individuals. Currently we have considered AP203 [3] - the most widely used Application Protocol (AP) for the exchange of Computer-Aided Design (CAD) files - and STEP Part 21 [4] CAD files - CAD files conformant to the data exchange format defined in Part 21 - for schema level conversion and instance level classification respectively. We have implemented a web application to demonstrate OntoSTEP. We are currently extending OntoSTEP to include information such as function, behavior, and assembly requirements.
Proceedings Title
Proceedings of the 6th International Conference on Product Lifecycle Management
Conference Dates
July 6-8, 2009
Conference Location
Bath, UK


STEP, OWL, ontology, reasoning, semantics


Krima, S. , Barbau, R. , Fiorentini, X. , Rachuri, S. , Foufou, S. and Sriram, R. (2009), OntoSTEP: OWL-DL Ontology for STEP, Proceedings of the 6th International Conference on Product Lifecycle Management, Bath, UK, [online], (Accessed April 13, 2024)
Created June 14, 2009, Updated October 12, 2021