Real-Time Satellite Constellation Scheduling for Event-Triggered Cooperative Tracking of Space Objects

This article investigates the satellite constellation scheduling problem for noncooperative space-object tracking. Different from the traditional Earth observation tasks, space-object tracking tasks require observation of fast moving targets that may have unpredictable trajectories, and estimation of the position of the targets through cooperative observation of multiple satellites. An agent-based scheduling framework is proposed to enable real-time, distributed scheduling of low Earth orbits constellation satellites for tracking noncooperative space targets. In the proposed framework, a nonlinear filtering of the targets’ trajectories is incorporated, and the observation satellites are dynamically allocated according to the status of the satellites and the states of the noncooperative targets. Specifically, event triggers of tracking space targets for activating task handover among satellites are defined and classified into five categories. The event-trigger processing and task response mechanism are embedded in the proposed scheduling framework. Thereafter, autonomously adjusting the observation-satellite sets can be achieved through distributed negotiation within only a few satellites. The effectiveness of the proposed method is validated by simulating scenarios of tracking targets without or with maneuvers.