Global Analysis of Eclipse Avoidance for Long-term Quasi-DRO Orbit

This investigation examined a practical strategy for global analysis of eclipse avoidance for long-term quasi-DRO. Firstly, the 2:1 resonance quasi-DRO family in CRTBP is numerically constructed, and the long-term quasi-DRO for 4-years is obtained and then transformed into a convergence trajectory in the ephemeris model. Secondly, the shadow geometry and path constraint are proposed, the latitude of invariant curve and insertion epoch are selected as key flight parameters, and the maximum duration of a single eclipse and minimum eclipse interval are proposed to describe the duration and frequency of eclipse event respectively. A two-level strategy to optimize eclipse avoidance is proposed, while level-1 utilizes grid search and level-2 uses a multi-objective genetic algorithm. The optimization results demonstrate that long-term quasi-DRO is not eclipse-free available from 2024/01/01 to 2028/01/01, but it has a shorter single eclipse duration than long-term DRO. An umbra-free trajectory is searched when only considering the path constraint of the umbra, which is not possible for long-term DRO.