Constellation Reconfiguration Strategy for Emergency Multitarget Continuous Coverage Using Low Thrust

In recent years, constellations have received widespread attention due to their potential to provide services including telecommunication, Earth observation, and so on. One promising method to increase the operational responsiveness of the constellation is orbital maneuvering. To this end, this paper establishes a general framework for low-thrust maneuvering and constellation reconfiguration strategy achieving emergency multitarget continuous coverage. By integrating analytical methods with the Broyden–Fletcher–Goldfarb–Shanno algorithm, a low-thrust four-stage maneuvering strategy is proposed, achieving coordinated sequential convergence of all orbital elements for circular orbits. Furthermore, a multitarget coverage orbit determination method based on sequential quadratic programming is proposed to facilitate constellation reconfiguration for continuous coverage. The proposed methods are validated through extensive Monte Carlo simulations involving a large number of randomly generated test scenarios, demonstrating significantly improved range of application and precision. A 360-satellite Walker–Delta constellation case demonstrates that, when combined with low-thrust maneuvers, the proposed methods enable continuous access to 10 emergency targets while reducing the maximum revisit interval up to 87.0%, significantly improving operational flexibility and system performance. In conclusion, the proposed framework not only exhibits computational efficiency but also demonstrates significantly application range improvement compared to previous studies, laying a foundation for the operational management of future large-scale space systems, including megaconstellations.