Space Debris Active Interception Using Spacecraft Swarm Based on Differential Game Theory

This paper studies the space debris active interception using spacecraft swarm based on differential game theory. Our model situates a high-value target spacecraft at the origin, with multiple debris approaching the target, and a group of protective spacecrafts (protectors) attempting to intercept the debris. The protectors are capable of executing orbital maneuvers utilizing thrusts of limited magnitude, while the debris has an initial acceleration in random direction. The distance between spacecrafts and debris is relatively small so that linear Clohessy-Wiltshire equations can be applied. A saddle solution is derived for the debris interception case and maximum time limit is calculated. Subsequently, a control strategy is proposed to guarantee that one single interception will be finished within the time limit. In addition, the lower bound of distance between debris and the target is estimated. Task assignment of multiple protector interception is then given. The efficacy of the proposed method is substantiated through numerical simulations.