System Architecture Study of On-Orbit Servicing Infrastructure Deployment Scenarios

This paper presents a systems architecture study to analyze and identify optimal systems architectures for on-orbit servicing (OOS) infrastructure. In this work, we consider on-orbit servicing in its functionalities of spacecraft refueling, refurbishing, upgrading, and orbit transfer services, as potential means for lifetime extension of existing satellites in orbit and last-mile orbit delivery for new launches. The main goal of this paper is to identify optimal OOS systems architectures for proxy figures of merit evaluating system-level performance for the functionalities mentioned above. In the assessment, we consider two servicing strategies, including on-orbit satellite refurbishing and refueling. We consider scenarios with a fixed number of servicing modules (1 servicer + 1 fuel depot) and a fixed number of client satellites (two co-orbital customers) to investigate the impact of servicing strategy (hub-and-spoke/point-to-point) and the choice of servicing elements’ parking orbit (LEO/GEO) on their masses, fuel demand, and the overall mission duration. Initial orbital location options of the OOS infrastructural elements are then determined based on the optimal accessibility to the customer satellites. A set of parametric models, including the OOS infrastructure mass budget, is developed for the analysis. We consider and evaluate alternatives of on-orbit servicing using single-stage and multiple-stage OOS modules and derive conclusions related to technology selection as well as delta-V allocation. Our results set the basis for further exploration of this topic in the future and define a parametric methodology for deriving traceable, quantitative estimates of OOS performance that decision-makers could use to inform the development and evolution of future on-orbit services.