Concept of the asset administration shell as a software-defined system

Due to the ongoing competition on the global markets, the functionality and adaptability of future production systems has to be highly improved. This can be achieved by applying advanced information and communication technologies, which leads to cyber-physical systems (CPS). CPS provide a bidirectional information flow between products, machines and top-floor systems, thereby enabling the instant adaptation of each process to external and internal conditions. This requires interoperability between the different components, thus leading to a highly flexible network. The huge variation of components in production systems and the tight coupling of software and hardware makes it difficult to develop such a unified communication standard. By transforming current CPS into software-defined systems (SDS) the standardization of the interfaces can be simplified and their functionality can be hugely increased. A first step was taken by the German high-tech strategy Industrie 4.0, which aims at developing binding standards for the interface of CPS in the production process. A so called asset administration shell (AAS) has been developed, which is a framework for the middleware between the existing machines and external networks. This contribution presents an approach for the application of the AAS as a software-defined system. Based on the analogies between SDN and AAS, the necessary alterations of the AAS are examined. With consideration of the requirements for industrial CPS, a concept for the implementation of an SDS-based AAS is introduced. The proposed architecture is applied in a use-case for two interconnected CPS.