Migration of Legacy Industrial Automation Systems in the Context of Industry 4.0- A Comparative Study

Automation systems are driven by industrial requirements such as sustainability, flexibility, efficiency and competitiveness. Those in turn are driven by a societal threats such as impacts on environment, sustainability of energy & natural resources, globalization, and rapidly changing market trends. A specific case of automation system engineering, concerns with the reengineering of old systems, in order to upgrade to a newer technology version; is referred as “Migration”. The engineering process of automation systems is a challenging job; in which, it’s required to realize and formulate the desired functionality and turn it into a physical system that fulfills the required process objectives, consequently selection of the most suitable engineering tools and methodologies to achieve that objectives. Although, most engineering specializations and application domains have developed a standardized engineering tools and methods. However, these standards vary greatly because the interaction between different specializations and domains are limited. Therefore, there are a continued efforts for having a common and unified ones. The other challenge in the engineering process is due to the increased complexity of automation systems, and accordingly, increased functionalities and amount data processing. These challenges makes the use of new technologies, engineering tools and methodologies to become a task that must be faced. In the context of the fourth industrial revolution (industry 4.0), the development and adaptation of more smart, more inter-connected automation systems, is a coherent approach to the engineering and management of the System of Systems (SOS). That system, which connects a massive numbers of devices, expected to be operating across multiple automation domains and serving different specializations. The SOS will utilize the industry 4.0 technologies such as internet of things (IoT), cyber physical systems (CPS) and cloud computing. In the same context; the engineering of SOS has to consider critical challenges faced by the legacy automation systems such as: 1) integration with the aforementioned technologies. 2) Interoperability between varies IoT devices and existing system. 3) Guarantee of stable performance of the system in regards to latency, availability and real-time information transfer. 4) Scalability and safety of process know-how and automation system related information. 5) Ease of application. 6) Feasibility of multi-vendor and multi-stakeholders integration. In this paper we present a comparative study for different migration strategies of old automation systems; with emphasis on migration of the two most widely systems, DCS and SCADA.