Optimized model-based design space exploration of distributed multi-orbit multi-platform Earth observation spacecraft architectures

Satellite architectures where networked, heterogeneous observation nodes capture data in a distributed manner are seen as feasible solutions to address the needs of next-generation Earth observation services (i.e. higher spatial, spectral and temporal resolutions at viable costs). Nevertheless, the problems that designers face when approaching these systems-of-systems are still eclipsed by the heterogeneity, dimensionality and multi-level complexity of those. In spite of the many underlying technological challenges, how to optimally architect distributed satellite systems, remains an open source of debate. In this context, this paper presents a design-oriented methodology that is aimed at providing high-level design solutions for this type of architectures in generic EO use-cases. In order to find optimal solutions, the methodology detailed in this paper is grounded on an aggregated architectural figure-of-merit that compresses: (a) system-level performance metrics; (b) use-case requirements; (c) development and launch costs; and (d) a set of architectural quality attributes. The latter contributing term models, assesses and weights several of the so-called 'ilities' of an architecture and allows to select designs that exhibit some desired qualities. With a dimensionality of more than five thousand architectural alternatives, the study has been illustrated with a marine weather forecast use-case. Both the exploration of design alternatives and the analysis of the results have shown the benefits of medium and small satellite platforms and have stressed their potential in the design of distributed satellite systems. Finally, this paper concludes by suggesting that this very optimization framework and methodology could also be used for a quantitative gap analysis aiming at deriving the technological road map for future engineering teams.