Encircling Hostile Spacecraft Through Constellation Collaboration: A Differential Game Approach to Orbital Pursuit-Evasion

Recent advancements in large-scale constellation architectures provide a foundation for spacecraft clusters to effectively achieve the threat interception in the congested orbit. To address this issue, a containment-oriented collaborative interception framework for the multispacecraft system is designed. First, a relative dynamics model capturing pursuer-evader interactions is established, anchored to the orbit threat as a reference point. An objective function incorporating a relative distance penalty term is formulated for the individual spacecraft. Subsequently, an integrated objective function is constructed and applied to all spacecraft. Second, the optimal interception strategies for the multispacecraft system are derived and simplified by identifying the sufficient conditions guaranteeing strategy uniqueness. Furthermore, the equivalence between the integrated model and the multiagent model in terms of optimal interception strategies is rigorously proven, along with a computationally efficient solution. Finally, the effectiveness of the proposed interception strategy is validated through high-fidelity numerical simulations.