Towards an Ontology-Based Generic Interface for Field Device Capabilities in Automation Systems

Field devices play an important role in the automation industry, providing the means to sense and control industrial processes. With the emergence of the Industry 4.0 strategy within the last decade, field devices now require an intelligent description that enables interoperability regardless of communication protocols and standards. Organizations such as the OPC UA Foundation and the Industrie 4.0 Platform are leading the way with standardized metadata models for describing intelligent systems. These standards enable the definition of interoperable semantic models that provide static and dynamic information for sensors and actuators. However, an open issue is the definition of a generic interface that abstracts the specific domain concepts from the different standards and field device organizations. In this paper, we propose an ontology-based interface to obtain generic field device capabilities and their relation to a field device-specific implementation. This approach allows industrial systems to automatically retrieve information from field devices without having to understand the specific semantics of a protocol and provides a bridge between the raw process data and a generalized definition that can be reused across devices. A proof of concept is presented with the integration of the generic interface for field devices and its implementation on a Programmable Logic Controller with a CODESYS runtime.