Three-dimensional time optimal multi-reversal orbit by using high performance solar sails

In this paper a new family of three dimensional (3D) non-Keplerian orbits is produced by using a high performance solar sail. A sailcraft departs from Earth orbit in the ecliptic plane to accomplish a periodic trajectory with orbital angular momentum varying four times over one period. Such a new kind of orbit is referred to as a "multi-reversal orbit". It is symmetrical with respect to the plane which contains the Sun-perihelion line. Such a good property benefits the calculations and reduces the simulation effort. As a preliminary design, an ideal solar sail is adopted as well as a 3D dynamic model in the heliocentric inertial frame. In order to find the minimum periodic orbits, the problem is addressed in an optimal control framework solved by an indirect method. Two typical 3D multi-reversal orbits are obtained with different orbital constraints. The quasi-heliostationary condition near its two aphelion points, which are suitable for in-situ observations, is discussed. Its capability to obtain rectilinear trajectories not in the ecliptic plane is also demonstrated using numerical simulations. A comparison between these two typical orbits is conducted to show more details about this new orbit. Differences between the 3D multi-reversal orbit and double angular momentum reversal orbit are given to fully present the advantages of the multi-reversal concept. As a result of its attractive mission scenarios this new kind of orbit could enhance the development of sail technologies although the sail performance is beyond the current capabilities.