Trajectory design and orbit maintenance strategies in multi-body dynamical regimes.

摘要

Regions of space in which multiple, simultaneous gravitational influences are present often give rise to dynamically complex behavior. Thus, design and maintenance of trajectories in these complicated environments is generally nontrivial. To address these challenges, the focus of this research effort is the development and application of innovative strategies to enhance trajectory design and orbit maintenance capabilities in multi-body dynamical regimes.;A simplified approach for generating unstable quasi-periodic orbits identified on Poincaré maps is introduced, one that leverages existing differential corrections procedures and well-understood unstable periodic solutions in the restricted three-body problem. This approach enables the comparison of numerous unstable quasi-periodic solutions since they are viewed and analyzed simultaneously. Such a capability offers valuable insight during the post-mission analysis of the ARTEMIS Earth-Moon libration point orbits; the strategy is also useful as a means of quickly exploring the design space and completing a trade analysis as demonstrated on quasi-periodic Sun-Earth L1 trajectories applicable to future missions such as DSCOVR. Multi-burn Earth-L1/L 2 transfer trajectories relevant to potential human operations in the vicinity of Earth-Moon libration points are also explored. These transfers incorporate a close lunar passage in an effort to decrease the time-of-flight and Δ-V cost for transfers associated with delivering spacecraft to various members of the Earth-Moon L1 and L2 halo orbit families.;Orbit maintenance in multi-body dynamical environments is addressed through the development of a flexible and robust long-term stationkeeping strategy designed to both maintain sensitive orbits for an arbitrary duration and to meet a set of precise end-of-mission constraints. The strategy is very general and is applied to approximate operational stationkeeping costs for a variety of Earth-Moon libration point orbits of interest for future scientific and/or human exploration activities. A related deterministic maneuver planning approach is introduced to mitigate an undesirable out-of-plane amplitude evolution in quasi-periodic libration point orbits as part of a robust global search procedure.