Spacecraft Trajectory Design Strategies Based on Close Encounters with a Smaller Primary in a 4-Body Model

Abstract

In spacecraft trajectory design, ΔV is limited and it becomes necessary to alter the characteristics of an orbit through other means. For example, close encounters of one or several moons in a planetary system can be employed to alter the shape of the orbit. Also, if the spacecraft is oriented favorably with respect to the sun, the solar gravity can be employed to alter the shape of the planetary orbit. When combined, the results can be dramatic. In this investigation, an efficient strategy to incorporate multiple gravity fields in the initial trajectory design process is explored.  , relative to the planet-moon rotating x-axis. Various investigations of orbits in multi-body regimes, including comets and other solar system particles, as well as spacecraft, employ the kick function to lend insight to the problem. Malyshkin and Tremaine 10 represent the kick function as a continuous interpolation function determined from a numerically integrated set of trajectories and apply it to the problem of the orbital evolution of comet trajectories, considering the probabilities of cometary survival. Zhou, Sun, Zheng, and Valtonen 11 derive the kick function from an expansion of the equations of motion in the Circular Restricted 3-body Problem (CR3BP) and employ it to study the transfer of comets from the Oort cloud to the inner solar system due to the gravitational effects of Jupiter. Pan and Sari 12 integrate the torque exerted