Locally-Optimal Electric Sail Transfer

This paper investigates the potentialities of the Electric Solar Wind Sail (E-Sail) for designing different mission scenarios based on locally-optimal control laws. The latter are obtained by maximising (or minimising) the instantaneous variation of a suitable combination of the spacecraft non-singular orbital elements related to the characteristics of both the parking and target orbit. The results associated to near-optimal trajectories can be used as a starting guess for a succeeding analysis of optimal transfers, involving the spacecraft transfer trajectory that minimizes the total flight time. In particular, the paper uses the most recent E-sail mathematical model that relates the propulsive thrust with the spacecraft attitude.