Multi-Objective Manoeuvring Optimization for Multi-Satellite Responsive Earth Observation

Abstract

Many space missions require that an area of interest on the ground is observed in a timely manner. Several approaches have been proposed in literature for this purpose, which involve modifying the ground track of an in-orbit satellite to overfly one or more Earth sites. Multi-satellite systems can clearly provide advantages for addressing this task in terms of responsiveness. In this context, this paper proposes a decision-making architecture to select the optimal manoeuvring or non-manoeuvring solution that enables a set of multiple sensor-equipped satellites in low Earth orbit to observe an area of interest in a timely fashion. For satellites that do not overfly the Earth site within the specified time period, dual coplanar impulsive manoeuvres are designed by applying a sensor-aware ground-track adjustment method. In particular, sensor footprints and percentage coverage of the assumed areas of interest are explicitly taken into account. A multi-objective optimization problem is then solved to determine which satellite provides the best solution to cover the area of interest in terms of fuel consumption (if ground-track adjustment is required) and time to overflight. Both simulated and real-world scenarios are considered to numerically validate the proposed methodology.