Interoperability levels and challenges of digital twins in cyber–physical systems

Industry 4.0/5.0 has brought together technologies like Internet of Things (IoTs), Industrial IoT (IIoT), Cyber–Physical Systems (CPS), Edge Computing, big data analytics, communication technologies (4G/5G/6G) and Digital Twins (DTs), aiming for more intelligent, interconnected systems. However, their real-time efficiency hinges on how well these components integrate and interact. This paper examines the interoperability levels and challenges of integrating Digital Twins within edge-enabled Cyber–Physical Systems. Our research explores the existing methods and frameworks for integrating multiple digital twins into a CPS setup. This study focuses on two key research objectives. The first is delineating interoperability levels within DT deployments in CPS setups. The second examines various interoperability challenges in integrating DTs in the context of CPS. A literature survey is conducted on the existing scholarly literature, industrial use cases, and reports. We identified 77 interoperability challenges and proposed an interoperability framework for DTs, involving six levels i.e. technical, syntactic, semantic, pragmatic, dynamic and organizational . We further categorized all the 77 challenges into 33 subthemes and mapped them across the 6 levels. The findings synthesize these challenges into a framework, offering a structured lens through which practitioners can view the adoption and effective use of interconnected DTs in CPS. This contribution is paving the way for future research and development endeavors, aiming to explore fully integrated, efficient, and intelligent CPS within the realm of Industry 4.0/5.0.