AAS will become synonymous with the digital twin in its future, fully enhanced version. As soon as the meaning of the digital twin finally morphs into the third interpretation, the differences between it and the AAS will disappear. And what is an Industry 4.0 component? It is the physical asset together with its Asset Administration Shell/digital twin. It is an Industry 4.0 enabled device, that can register itself in the I4.0 network and be identified, explored and processed via Industry 4.0 interfaces. Finally, the evolution of the term “digital twin” offers a powerful illustration of the upcoming revolution. The future digital Fig. 2: Three-level concept of a cyber-physical system [4]. The evolution is ongoing. The term “digital with their individual digital twin whenever twin, in combination with cloud technology, twin” is slowly changing its meaning yet necessary at a later date. apps and algorithms, has the potential again. In a digital future, we will need to revolutionize every aspect of industry digital twins as comprehensive physical and Hence, the digital twin will become a power- because it touches every aspect. The functional models for every physical asset ful electronic data object with interfaces: possibilities are endless, the digital twin is [3], e.g. a component, product or system. it will hold or reference all useful data (see only the beginning. Step-by-step, the digital twin will cover all Fig. 1), some data will be semantically stan- the useful information which is relevant dardized (e.g. properties, geometry, topo- across the lifetime of the related asset, from logy), other data will be of a proprietary the idea to the engineering, logistics, ope- nature (e.g. ABB function blocks). Internally, ration, maintenance, reuse and destruction. the digital twin will communicate with its A future digital twin may contain a simula- physical asset, e.g. via proprietary interfaces. tion model, but also a 3D model, hundreds However, externally, it will communicate via of properties, historical data, handbooks, well-defined Industry 4.0 interfaces. installation guidelines, proprietary function blocks, interlockings, state models, alarm The future digital twin will incorporate both and event definitions etc. Friends of the first data and interfaces and be similar to a soft- or second interpretation may be surprised to ware driver – but far more. It will be a multi- hear that it might even have no simulation facetted digital counterpart of the real asset, model at all, e.g. for static assets. It will be embedded in the Industry 4.0 ecosystem, stored in a future Industry 4.0 infrastructure, access point for a new generation of apps be searchable, explorable, associated with and algorithms, mediator between future and sometimes connected to its real coun- Industry 4.0 services and the real world. terpart. It will not be hidden in proprietary Fig. 2 shows the digital twin in the middle simulation tools. Sales tools, simulation of the tree layer concept of a cyber-physical tools, engineering tools, certification tools, system [4] in an Industry 4.0 environment. maintenance tools etc. may connect to digital twins for sales, engineering, certifi- And what is the Asset Administration Shell cation, maintenance, simulation or optimi- (AAS) [5]? According to [6], it contains the zation purposes, sometimes long before the information and I4.0 interfaces for an asset. related real assets are ordered. It will be Sounds similar to the digital twin, doesn’t possible to associate delivered real devices it? This is exactly what [6] proposes: the Reference: [1] Kagermann, Henning; W. D. Lukas and W. Wahlster: Industrie 4.0: Mit dem Internet der Dinge auf dem Weg zur 4. industriellen Revolu- tion. VDI Nachrichten (2011). [2] M. Shafto; M. Conroy; R. Doyle; E. Glaessgen; C. Kemp; J. LeMoigne and L. Wang: Draft model- ing, simulation, information technology & pro- cessing roadmap. Technology Area, vol. 11, 2010. [3] S. Boschert and R. Rosen: Digital twin the simulation aspect. In Mechatronic Futures. Springer, 2016, pp. 59–74. [4] R. Drath and A. Horch: Industrie 4.0: Hit or hype?. IEEE industrial electronics magazine, vol. 8, no. 2, pp. 56–58, 2014. [5] Struktur der Verwaltungsschale: Fortentwick- lung des Referenzmodells für die Industrie 4.0- Komponente, April 2016. [Online]. Available: [4] https://www.plattform-i40.de/I40/Redaktion/DE/ Downloads/Publikation/struktur-der-verwaltungs- schale.html. [6] C. Wagner; C. J Grothoff; U. Epple; R. Drath; S. Malakuti; Grüner S.; Hoffmeister M.; Zimmermann P.: The role of the Industry 4.0 Asset Administration Shell and the Digital Twin during the life cycle of a plant. In: Proceedings of the 2017 IEEE Conference on Emerging Technologies Factory Automation (ETFA 2017), Limassol, Cyprus, 2017. 7 vis IT Industrial IoT