A model-based engineering process to explore resilience attributes in systems-of-systems

Systems-of-systems (SoS) are an ongoing focus of many organisations interested in the development of products and services in environments with great uncertainty. SoS are heavily interconnected entities which comprise of a vast number of constituent parts, both technical and socio,that are inherently complex and must demonstrate levels of resilience. Designing for resilience in SoS has been a great challenge due to the nature of such systems. With no overarching management to steer the SoS in a directed manner, there is a need to investigate novel processes and methods to better understand resilience within a SoS context. This thesis aims to develop new processes to aid systems engineers, and industry practitioners to understand and design for resilience from a SoS perspective. Resilience in this instance is regarded at the SoS-level where the underpinning connected systems demonstrate resilience in the form of a range of supporting properties which lead to improved/ sustained performance. These properties (which are commonly referred to as non-functional properties or “ilities”) will be referred to throughout this thesis as resilience attributes and are seen as designable features which can be architected at the early phases of SoS development. Such attributes include reliability, redundancy, flexibility, availability, and safety. The research methodology applied was participatory research to explore the requirements for a model-based engineering process to understand resilience and to explore SoS resilience attributes. The methodology was applied to capture requirements for a set of processes that are reflective of real-world problems within real industrial organisations. An extensive application of case study investigations covered SoS from multiple domains with the inclusion of industry and subject matter experts (SMEs) to elicit requirements for a SoS-focused resilience process and a novel architecture viewpoint. The four case studies were of the classification directed and acknowledged for they have higher levels of control within them and that can be directly evolved by leading stakeholders to implement changes such as increased capabilities and increase resilience. The case studies were conducted in the domains of emergency response, water supply systems and the air transportation system. [Continued ...]