Optimal solar sail interplanetary heteroclinic transfers for novel space applications

This paper investigates the design and optimization of solar sail interplanetary trajectories connecting both Libration Point Orbits (LPOs) and Distant Periodic Orbits (DPOs) belonging to different restricted three-body problems: namely the Sun-Earth model and the Sun-Venus one. Assuming the Sun always as first primary, the Earth and Venus are the second primary, and their relative models are coupled together with the view of defining heteroclinic connections. On suitable Poincare sections, solar sail sets are constructed to obtain transit conditions from LPOs of the departure dynamical system to either LPOs or DPOs of the arrival one. Starting from initial guesses that assume a constant attitude of the solar sail, an optimal control problem is formulated, encompassing a trade-off between minimum transfer time and minimum solar sail steering effort, and it is solved with a direct pseudospectral method. At the optimization stage, variable attitude solar sails are investigated, assuming spacecraft with different control capabilities.