OPC-UA and DPWS interoperability for factory floor monitoring using complex event processing

Future manufacturing systems will require to process large amounts of complex data due to a rising demand on visibility and vertical integration of factory floor devices with higher level systems. Systems contained in higher layers of the business model are rapidly moving towards a Service Oriented Architecture, inducing a tendency to push Web Technologies down to the factory floor level. Evidence of this trend is the addition of Web Services at the device level with Device Profile for Web Services and the transition of OPC based on COM/DCOM communication to OPC-UA based on Web Services. DPWS and OPC-UA are becoming nowadays the preferred options to provide on a device level, service-oriented solutions capable to extended with an Event Driven Architecture into manufacturing systems. Furthermore, it has been shown that interoperability between these two can enhance the implementation of a Service Oriented Architecture for industrial purposes. This paper proposes an implementation solution for supervision and monitoring of manufacturing systems on the factory floor level. The proposal involves management of heterogeneous events incoming from OPC-UA and DPWS using a complex event processor. The approach presented is applicable in distributed systems that may require an advance interpretation of data incoming from these two communication protocols.