Control dispatch optimization in space missions

The present thesis work aims at providing analysis and design tools to tackle complex thruster placement and orientation problems for a spacecraft with electric propulsion systems. The methods developed have been tested and applied within the first design phases of the Next Generation Gravity Mission, carried on by Thales Alenia Space, as an instrument to identify feasible layout configurations capable of providing proper redundancy in case of a random single thruster failure and comply with the input control laws. In order to tackle effectively the relevant thruster layout optimization problem, an ad hoc optimization methodology has been introduced. The idea consists in partitioning the thruster layout task into two much easier subproblems and in solving the first one by following a global approach to find a sub-optimal solution. It is taken as initial solution of the second subproblem, solved by a local approach, through the Sequential Linear Programming (SLP) method.