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OntoSTEP: OWL-DL Ontology for STEP



Sylvere Krima, Raphael Barbau, Xenia Fiorentini, Sudarsan Rachuri, 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] and STEP Part 21 CAD (Computer-Aided Design) files for schema level conversion and instance level classification respectively. We will describe a web application to demonstrate OntoSTEP. We are currently extending OntoSTEP to include information such as function, behavior, and assembly requirements.
NIST Interagency/Internal Report (NISTIR) - 7561
Report Number


STEP, standards, semantics, ontology, OWL-DL, EXPRESS


Krima, S. , Barbau, R. , Fiorentini, X. , Rachuri, S. and Sriram, R. (2009), OntoSTEP: OWL-DL Ontology for STEP, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed February 25, 2024)
Created May 3, 2009, Updated October 12, 2021