A Fractionated Spacecraft Architecture For Earth Observation Missions

Abstract: A fractionated spacecraft is a satellite architecture for which the functional capabilities of a conventional spacecraft are distributed across multiple modules (spacecrafts) which fly separately and interact through wireless links. Removing the physical dependencies between the resources, or subsystems, of a spacecraft, brings several attributes, such as flexibility and robustness, which can be exploited for the benefit of the earth observation payloads. In this manner, an infrastructure network which is composed of resource modules can be put into a sun-synchronous orbit for the benefit of such payloads. However, fractionating a spacecraft and letting the different subsystems fly separately leads to several technological concerns which are related to the shared resources within the fractionated spacecraft network. Regarding these technology implications, collision free close proximity cluster flying configurations were evaluated initially. Then a realization approaches were also discussed via system analysis for shared resources, namely guidance, navigation and control, communications, data handling and power. Notional spacecraft architecture was determined in the light of these discussions and the sizing of the modules within this architecture was made based on an incremental launch, or one module per launch, approach. Finally it was concluded that the resource capability increase is more efficient in terms of data storage and processing when compared to wireless power transfer.