A spacecraft needs to simultaneously provide orbital and attitude control but these are in general treated as separate systems. Normally the attitude control is conducted via reaction wheels but can in scenarios with high manoeuvrability demands be handed over to pure thruster control. In specific cases the reaction wheels are removed from the spacecraft to save mass. If both the orbital and attitude control is regulated with thrusters, there is a potential to save fuel in a combined control strategy. Model predictive control has been shown to be a viable method for orbital control with a fuel minimising objective. This thesis investigates a combined orbital and attitude model predictive control strategy. Three test cases are simulated with a specific thruster configuration; maintaining a passive orbit relative to a target, large-angle reorientation and repositioning, and rendezvous. Preliminary results show that including the coupled dynamics lowers the overall fuel consumption while satisfying requirements on position and attitude in scenarios where the timescale of the orbital and attitude control is similar.
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