Article Title

Optimization of observing sequence based on nominal trajectories of symmetric observing configuration


branch and bound, optimization, symmetric observing, configuration, GTOC, low thrust


This paper presents the crucial method for obtaining our team’s results in the 8th GlobalTrajectory Optimization Competition (GTOC8). Because the positions and velocities ofspacecraft cannot be completely determined by one observation on one radio source, thebranch and bound method for sequence optimization of multi-asteroid exploration cannotbe directly applied here. To overcome this difficulty, an optimization method for searchingthe observing sequence based on nominal low-thrust trajectories of the symmetric observingconfiguration is proposed. With the symmetric observing configuration, the normal vector ofthe triangle plane formed by the three spacecraft rotates in the ecliptic plane periodically andapproximately points to the radio sources which are close to the ecliptic plane. All possibleobserving opportunities are selected and ranked according to the nominal trajectoriesdesigned by the symmetric observing configuration. First, the branch and bound method isemployed to find the optimal sequence of the radio source with thrice observations. Second,this method is also used to find the optimal sequence of the left radio sources. The nominaltrajectories are then corrected for accurate observations. The performance index of ourresult is 128,286,317.0 km which ranks the second place in GTOC8.


Tsinghua University Press