A Robust Low-Frequency Control Strategy for Formation Keeping in Low Earth Orbit

This paper addresses the challenge of minimizing the control frequency in satellite formation-keeping missions under the constraints of real-world orbital perturbations and actuator uncertainties. The focus is on a four-satellite formation flying in near-circular, frozen Sun-synchronous orbits at approximately 500 km altitude. A robust control framework is proposed that integrates a modified relative orbital element (ROE) model, Monte Carlo-based reachability forecasting, and event-triggered thrust scheduling. The system accounts for thrust magnitude fluctuations, occasional interruptions, and angular misalignments. A multi-fidelity simulation platform validates the strategy's effectiveness in reducing actuation frequency while maintaining tight formation geometry. The method is shown to be fault-tolerant and resource-efficient, making it ideal for long-duration missions using electric propulsion systems.