Software Architecture for Industry 4.0

The Industry 4.0 (I4.0) revolution is a transformation of current practices towards more connected production, impacting production, improvements, and distribution of products. Companies will integratemore advanced and versatile robotic and automated solutions, sensors,and technologies such as the Internet of Things (IoT), Cyber-physicalsystem (CPS), big data analytics, cloud, Artificial Intelligence (AI),and simulation in their production system. Connecting all these heterogenous systems provides flexibility and opportunities to react andchange production, accommodating more fluctuating customer needs.A danish survey predicts a 20-50% reduction in time to market, 30-50% reduction of total machine downtime, 20-50% reduced cost forinventory holding, and the quality cost is reduced by 10-20% by adopting I4.0. The World Economic Forum (WEF) reports that a companyreduced its cost by 10.000 EURO per year per machine by adoptingI4.0, e.g. by having software that connects to the machines and cananalyze the machines’ data. It is estimated that I4.0 will lead to 20-30%productivity improvement. Therefore it makes it compelling to consider software to connect advanced production equipment, sensors,and various technologies to form an intelligent production network.A solution to connect heterogeneous systems seamlessly is throughmiddleware software which will be the glue between systems and facilitate information flows. This Ph. D. thesis seeks to design, develop andevaluate middleware Software architecture (SA) for flexible productionsystems with a focus on Quality Attribute (QA) requirements. To doso, the University of Southern Denmark (SDU) Industry 4.0 Laboratory(I4.0 Lab) will be used as the frame to analyze production equipmentand technologies and to design, develop, and evaluate middlewareSA for a production system. In this Ph. D. thesis, interoperability andreconfigurability have been found to be important for a middleware SAto support flexible production. Middleware interoperability is a fundamental QA to understanding how systems can exchange meaningful communication and a driver to exploit the potential of other technology solutions. Reconfigurability is an essential quality to a flexibleproduction system to handle effective readjustment of the productionflow and to accommodate changes in the physical environment. First,multiple levels of interoperability have been analyzed from an assetand middleware SA perspective. Next, a reconfigurability definitionhas been proposed, which is based on capability and configurationconcepts that also have been defined. A reconfigurability Quality Attribute Scenario (QAS) template has been analyzed, developed, andevaluated to specify QA requirements for middleware SAs. Lastly, areconfigurability QA requirement has been stated from the templatefrom which a reconfigurable middleware SA is designed, developed,and evaluated on production equipment in the SDU I4.0 Lab. ThePh. D. thesis contributes to developing knowledge on interoperabilitylevels for middleware SAs and a promising QAS template to specifyreconfigurability QA requirements for middleware SAs, as well as ademonstration of a developed reconfigurable middleware SA to support further development of flexible production systems in the contextof I4.0.