Abstract
Recently, various kinds of planetary explorations have become more
feasible, taking the advantage of low thrust propulsion means such as
ion engines that have come into practical use. The field of space
activity has now been expanded even to the rim of the outer solar system.
In this context, the Japan Aerospace Exploration Agency (JAXA) has
started investigating a Deep Space Port built at the L2 Lagrange point
in the Sun-Earth system. For the purpose of making the deep space port
practically useful, there is a need to establish a method to making
spaceship depart and return from/to the port.
This paper first discusses the escape maneuvers originating from the L2
point under the restricted three-body problem.
Impulsive maneuvers from the L2 point are extensively studied here, and
using the results, optimal low-thrust escape strategies are synthesized.
The paper presents, as the major results, the optimal escape and
acceleration maneuvers schemes using Electric Delta-V Earth Gravity
Assist (EDVEGA) technique, in which the comprehensive delta-V
evaluation method is presented. The results obtained are highly useful,
ushering the future solar system exploration era.
