Optimal low-thrust trajectories using nonsingular equinoctial orbit elements
Low-thrust propulsion was proven to allow substantial propellant savings with respect to high-thrust systems, at the price of increasing the time of flight. This work addresses low-thrust orbit transfer optimization, which consists in finding the thrust direction time history that minimizes the time of flight. The indirect heuristic method is outlined and employed. It is based on the joint use of a heuristic technique and the necessary conditions associated with the optimization problem.