Methodologies for the analysis of space systems supporting the decision making in the early design phases

Dealing with complex systems and SoS is not trivial, for several reasons. One of the most critical aspects of working with SoS is that traditional systems engineering and technical activities must be integrated with enterprise activities of strategic planning and investment analysis. The purpose of this thesis is to propose and describe methods capable of supporting the stakeholders involved in the design of complex systems and SoS. In particular, the focus is on the pre-conceptual design of a new system and the challenge is to allow the stakeholders choosing the right system to be built before the system engineers have done their job to a certain detail. To accomplish this ambitious goal, the research takes into account several disciplines usually far from the technical background of a space engineer and integrates them into the process of designing a space system. Most of the work done to solve the problems at the basis of making choices has been done in the economics and social sciences. Disciplines such as decision-making, systems dynamics, and multi- attribute utility theory have been considered and adapted for some use cases. In the first case study, the goal is to bring to light the gaps extant between what System Architects prioritize, and the preferences of potential System Users. To this purpose the proposed method aims at incorporating lifecycle properties (-ilities) in the concept design phase, by submitting attributes of these properties for the evaluation of two stakeholder representative groups. The case study refers to the integration of environmental measurements, coming from a GNSS-based remote sensing satellite constellation, as complementary data to the traditional weather-forecasting service, resulting in a new System of Systems. The method runs through an interview-based Quality Function Deployment process and collaborative sessions of teams of stakeholders. The strength of the formulation relies on the ability to treat a quantitative measure of the gaps extant between system’s desired capabilities as perceived by architects, and real end-users’ needs. The method can be potentially tested in a concurrent design environment as a complementary tool for eliciting requirements and suggesting the areas where investments and resources should be preferably allocated. Results can be used by researchers as pieces of knowledge to be further investigated, and by practitioners in development projects. The second case study is aimed at studying the pre-conceptual design phase of a mission of nanosatellites and ground-penetrators for Mars exploration. The goal was to use information on MEPAG prioritization to build a tradespace of design options. Tradespace then would have been offered to Decision Makers involved in the Mars Exploration Program steering committees as a mean to evaluate and explore ground-breaking alternative solutions and achieve the highest-priority science objectives. The results from the present case study show how many of the science goals identified by credible scientific groups in a wide variety of fields can be achieved leveraging heterogeneous and expendable assets. This concept shows promise for a future mission proposal that would most likely never even be considered by traditional mission managers who do not possess the tools to understand how value is being delivered, how risk can be acceptable, and opportunity can be pursued; the method and the modifications proposed in this work give mission managers the ability to weigh these options and how higher levels of satisfaction can be achieved in uncertain futures. The research presented in this thesis can be framed as work done in the field of decision analysis. This is a field of research that encompasses approaches for facilitating the decision making process. We propose methods and techniques to support the decision makers and system designers during the pre- conceptual design of complex systems. The methods have the potential to capture those interactions between the constituents of a System of Systems that decision makers could not recognize or underestimate. The analysis of the case studies results provided useful insights about how the stakeholders perceived the capabilities with respect to the needs drawn by the end-users, and led to the identification of major gaps, suggesting decision makers where and how better investing or saving resources.