Developing open source cyber-physical systems for service-oriented architectures using OPC UA

Cyber-physical systems (CPS) are key enabling technologies for the fourth industrial revolution, referred to as Industrie 4.0 or Industry 4.0. The Reference Architecture Model Industrie 4.0 (RAMI4.0) has recently been standardized and OPC Unified Architecture (OPC UA) is listed as the sole recommendation for implementation of a communication layer. Many automation and control systems offer already implementations of OPC UA but no satisfying implementation of OPC UA was found for Arduino, a popular platform for engineering physical computing systems. This paper presents open source integration and application of a customizable OPC UA server on an Arduino Yun board using open62541, an open source and free implementation of OPC UA. The Arduino board discussed in this paper offers hot-end closed-loop temperature control for a 3D printer but the temperature set value and control parameters can be manipulated and requested via OPC UA using OPC UA clients. The application is verified using Prosys OPC UA Client and UaExpert. The results of our research can be used for developing open source cyber-physical systems without specialized knowledge in microcontroller programming, bringing Industry 4.0 applications into classrooms without effort.