Basic Concepts on Systems of Systems

A System of System (SoS) stems from the integration of existing systems (legacy systems), normally operated by different organizations, and new systems that have been designed to take advantage of this integration. Many of the established assumptions in classical system design, such as e.g., the scope of the system is known, that the design phase of a system is terminated by an acceptance test or that faults are exceptional events, are not justified in an SoS environment. This is well represented by Table 1. In this chapter we present the fundamental concepts for Systems of Systems engineering established within the AMADEOS project, with the objective of proposing a shared System of Systems vocabulary and define an implicit theory about the SoS domain. The overarching concern of our work is to target the reduction of the cognitive complexity needed to comprehend the behaviour of a SoS by the application of appropriate simplification strategies [29]. In fact, the considerable cognitive effort needed to understand the operation of a large SoS is the main cause for the substantial engineering (and monetary) effort required to design and maintain many of today’s Systems of Systems. Our position is that the first important step of achieving simplicity is the development of an understandable set of concepts that describes the SoS domain. In fact, if the language used to talk about a domain contains terms with clearly defined meanings that are shared by a wide part of the domain community, then the communication of ideas among experts is simplified. Consequently, starting from a detailed analysis of the existing concepts for the SoS domain (e.g., from the projects DANSE [35], DSoS [7],