Abstract:

Agile earth observation satellite (AEOS) is a new type of satellite with high application potential, for its added observation opportunities and flexible time window from enhanced maneuverability. However, start time of observations is a continuous variable, so combination optimization modeling methods for non-agile satellites are not usable for it. This paper introduces characteristics of temporal dependence, hybrid of controllable and uncontrollable events, and resource’s over-subscribed. Temporal constraint network concept and temporal reasoning problem of AEOS has been presented. Equivalence of temporal constraint network and distance graph and Johnson algorithm for sparse networks has been analyzed. Then, an improved cycle checking algorithm for AEOS scheduling based on re-evaluating has been proposed, and a branch-prune algorithm based on constraint programming way was applied to get a consist solution. Finally some experiments were presented to prove the validity of the method. The results showed the efficiency and validity of the method in consist checking and searching of temporal constraints in AEOS scheduling.