COMBINING LOW-THRUST AND GRAVITY ASSIST MANOEUVRES TO REACH PLANET MERCURY

摘要

In this paper a direct method based on a transcription by Finite Elements in Time has been used to design optimal trajectories toward Mercury exploiting a combination of gravity assist manoeuvres and low-thrust propulsion. A multiphase parametric approach has been used to introduce swing-bys among thrust and coast arcs. Gravity manoeuvres are at first modelled with a link-conic approximation and then introduced through a full three-dimensional propagation including perturbations by the Sun. Different options corresponding to different sequence of gravity manoeuvres or launch opportunities are presented.