A System of Systems View in Early Product Development : An Ontology-Based Approach

Sammanfattning: The concept of system-of-systems is becoming increasingly common and relevant in many engineering applications. Today’s highly interconnected world entails that more and more systems have dependencies on other systems. This increasing number of interdependencies results in new levels of complexity that must be managed in the early development of new products. Different view-points must also be handled to understand the many layers of a system-of-systems and its surrounding context. An ever-changing future results in un-certainty about the operational environment but also other aspects, such as available technologies, which complicates the matter even further. Traditional approaches for early product development can be used to some extent, but the complexity, scale and sheer number of interconnections in system-of-systems require a holistic perspective to obtain an early understanding of the problem, design spaces, and multiple aspects involved. This dissertation aims to present a method that has been developed to address the demand for a more holistic system-of-systems view in early product development. Overall, the method consists of four parts that together show how design spaces for system-of-systems can be generated and later processed to find suitable solutions. Search and rescue operations have been used as examples of system-of-systems throughout this work and in the development of the presented method. The first two parts of the method are based on architecture frameworks and ontologies with description logic reasoning capabilities. An architecture framework is here used to break down system-of-system needs into functions to be fulfilled by constituent systems. Ontologies are thereafter used to represent the outcome and the resulting system-of-system design spaces with involved entities and their relationships. Description logic reasoning can subsequently be used to process the available design spaces and suggest suitable system-of-system solutions. The last two parts of the method build upon a concept exploration and estimation approach, together with visual analytics. The approach illustrates how individual system concepts can be estimated from an ontology-represented design space, and how visual analytics can be used to explore different system-of-system viewpoints at an early stage. Based on the outcomes of the presented method, this dissertation contributes a holistic take on early product development from a system-of-systems perspective.