Clarifying concepts of Metaverse, Digital Twin, Digital Thread and AAS for CPS-based production systems

With the quick advent and spreading of Industry 4.0, the paradigm of Cyber Physical Systems (CPS) is becoming a reality in production systems. As the term CPS suggests, the advanced production systems are made of a digital element and a physical one that work together to reach the desired functionality. The virtual element is made of various entities that are typically generically described as “a digital representation of a physical system”. However, this general definition often is referred to terms that are actually belonging to different concepts. These terms are Metaverse, Digital Twin, Digital Thread, and Asset Administration Shell. These terms often are independently used in literature and industrial initiatives without any clear understanding of how they relate to one another or what they signify. This paper wants to contribute to the scientific discussion on these concepts and aims at analyzing their meanings and key features through a literature study, by proposing a hierarchical view on the relationships between them, their roles and functions for CPS-based production systems.