Formation flying of multiple spacecraft collaborating toward the same goal is fastbecoming a reality for space mission designers. Often the missions require the spacecraft toperform translational manoeuvres relative to each other to achieve some mission objective.These manoeuvres need to be planned to ensure the safety of the spacecraft in the formationand to optimise fuel management throughout the fleet. In addition to these requirements is itdesirable for this manoeuvre planning to occur autonomously within the fleet to reduceoperations cost and provide greater planning flexibility for the mission. One such mission thatwould benefit from this type of manoeuvre planning is the European Space Agency’sDARWIN mission, designed to search for extra-solar Earth-like planets using separatedspacecraft interferometry.This thesis presents a Manoeuvre Planning Architecture for the DARWIN mission. Thedesign of the Architecture involves identifying and conceptualising all factors affecting theexecution of formation flying manoeuvres at the Sun/Earth libration point L2. A systematictrade-off analysis of these factors is performed and results in a modularised ManoeuvrePlanning Architecture for the optimisation of formation flying reconfiguration manoeuvres.The Architecture provides a means for DARWIN to autonomously plan manoeuvres duringthe reconfiguration mode of the mission. The Architecture consists of a Science OperationsModule, a Position Assignment Module, a Trajectory Design Module and a Station-keepingModule that represents a multiple multi-variable optimisation approach to the formationflying manoeuvre planning problem. The manoeuvres are planned to incorporate targetselection for maximum science returns, collision avoidance, thruster plume avoidance,manoeuvre duration minimisation and manoeuvre fuel management (including fuelconsumption minimisation and formation fuel balancing). With many customisable variablesthe Architecture can be tuned to give the best performance throughout the mission duration.The implementation of the Architecture highlights the importance of planning formationflying reconfiguration manoeuvres. When compared with a benchmark manoeuvre planningstrategy the Architecture demonstrates a performance increase of 27% for manoeuvrescheduling and fuel savings of 40% over a fifty target observation tour.The Architecture designed in this thesis contributes to the field of spacecraft formationflying analysis on various levels. First, the manoeuvre planning is designed at the missionlevel with considerations for mission operations and station-keeping included in the design.Secondly, the requirements analysis and implementation of Science Operation Modulerepresent a unique insight into the complexity of observation scheduling for exo-planetanalysis missions and presents a robust method for autonomously optimising that scheduling.Thirdly, in-depth analyses are performed on DARWIN-based modifications of existingmanoeuvre optimisation strategies identifying their strengths and weaknesses and ways toimprove them. Finally, though not implemented in this thesis, the design of a Station-keepingModule is provided to add station-keeping optimisation functionality to the Architecture.
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