Electric Sail Phasing Maneuvers for Constellation Deployment

The aim of this work is to investigate heliocentric phasing maneuvers performed by a spacecraft propelled by an Electric Solar Wind Sail, an innovative propellantless propulsion system. It is assumed that the sail may be controlled by varying its attitude, and by switching the tether grid off to obtain Keplerian arcs in the trajectory. The analysis is conducted within an optimal framework, whose aim is to find the minimum-time phasing trajectory for a given angular drift, and the corresponding time variation of the control variables. A typical phasing scenario is analyzed, by considering either a drift ahead or a drift behind maneuver option. We also investigate the possibility of using an Electric Solar Wind Sail-based deployer to place a constellation of satellites on the same heliocentric circular orbit. The corresponding flight times are obtained as a function of the sail performance and the number of satellites.