Service composition solutions based on an Industry 4.0-compliant asset administration shell service collector

Within the context of the Industry 4.0 and Smart Manufacturing, digitalized Assets of digital Ecosystems should be discovered by others Assets and communicate with each other through message passing. This will allow to create systems that enable distributed decision-making processes. Such systems are empowered by Low-Cost devices as processing and communication units, saving resources by atomizing functionalities and improving distributed systems to make them efficient and flexible. According to the Industry 4.0, Assets are represented in the digital world and its networks by the Asset Administration Shell (AAS). The AAS is utilized as the standardized form to expose Assets functionalities in form of services to be discovered and consumed by other Assets. When services are discovered, the orchestration of services with its service composition, comes into the picture enabling the decision-making processes within industrial environments. In this work, the authors are presenting a novel innovative service collector solution for supporting dynamic orchestration of services in an Industry 4.0 and Asset Administration Shell compliant digitalization infrastructure. On the basis of previous related works, an improved service discovery algorithm based on the Simple Service Discovery Protocol (SSDP) and Web-services that retrieves functionalities of Assets through embedded AAS deployed in a passive manner, two solutions to interact with discovered services are proposed in this paper. In the first solution, an Open-source Messenger Bot for user interaction is deployed on a Single-Board Computer allowing the execution of the following tasks: (i) service discovery algorithm, (ii) Hardware I/O interaction, (iii) calculations and graphs considering cloud datasets, (iv) interaction with cloud-based AAS, (v) email messages based on the results of the service discovery algorithm and, (vi) triggering of events to initiate the execution of message-based interactions between different deployed AAS. The second solution is performed by a multi-method simulation modeling tool. It composes the collected services by the service collector and organises them, in a sequential process where each collected service is called, according to the required functionalities of that process.