Solar sail heliocentric transfers with a Q-law

The propellantless working principle of a solar sail requires the total flight time to be minimized when looking for the optimal trajectory to reach a given target state. In this work the solar sail steering law is found by applying a Q-law algorithm, which aims at driving the spacecraft toward the final (target) orbit by decreasing the distance between actual and desired states or by increasing the rate of change of the state variables. A formulation of the Q-law algorithm for a solar sail-based mission is given, which accounts for the constraints along the transfer trajectory imposed by the sail thrust model. The performance of the proposed procedure, which represents the novelty of this work, is checked in some potential solar sail mission scenarios, including coplanar interplanetary transfers and the exploration of outer Solar System regions.