Robust Aero-Gravity Assisted Maneuvers for a Multi-Objective Interplanetary Trajectory Design Optimization

The paper proposes an approach to deal with the preliminary space mission analysis design of particularly complex interplanetary trajectories. According to an optimization approach, a multi-objective strategy is selected on a mixed continuous and discrete state variables domain to deal with possible multi-gravity aero-assisted maneuvers (AGA) as further degrees of freedom of the problem, in terms of both number and planets sequence selection to minimize both the Delta v demand and the time trip time span. The planet sequence and the planets to be used for the possible AGAs to optimize the criteria vector, together with the departure date and each Lambert arc time span constitute the control set of the optimization problem. Whenever an atmospheric maneuver is selected the consequent optimal control problem - related to the aerodynamic angles history - is solved by taking into account uncertainties on the environment and the initial conditions thanks to the differential inclusions method to project the hyper-box of the parameters/variables into the criteria space. In particular, as soon as an atmospheric maneuver occurs to be selected, the thermal flux is inserted into the cost function vector, to be minimized, and a robust control is obtained for the whole Pareto front set. The perturbed 2BP is applied to deal with the planetary approaching dynamics modeling. Some simulations results are discussed and the benefits of the AGA maneuver exploitation highlighted.