Global trajectory optimisation of a space-based very-long-baseline interferometry mission

GTOC is an event in which the best aerospace engineers and mathematicians worldwide challenge themselves to solve a complex problem that cannot be solved with standard optimisation tools. The 8th edition of GTOC is based on orbital mechanics with an important weight on optimisation. The description of the problem presents a three spacecraft con guration capable of taking measurements on the celestial sphere with VLBI instruments on board. The nal objective stands for the maximisation of a performance in- dex which depends in the course of action to measure di erent sources during a maximum mission time given. In this thesis, is suggested a method to obtain an optimal result. Besides, the complexity of the mission demands a simpli ed and optimal approach to the problem as there are not methods available tu fully solve it. The approach presented support itself on a fuel-e cient concept, using the propulsion systems on board only when is strictly necessary. The importance of gravity assists during the mission subjects the problem to reach the Moon with the available spacecraft as many times as possible. The obtention of resonant orbits after a yby gives the opportunity to multiple fuel-free orbital transfers while measurements are taken between ybys. The nal optimal trajectory is determined using a MOEA which optimise the solution for each resonant orbit obtaining the maximum value of the performance index minimising time for each yby in order to explore the maximum amount of possible resonant orbits.Ingeniería Mecánic