Asteroid Flyby Cycler Trajectory Design Using Deep Neural Networks

Abstract

Asteroid exploration has been attracting more attention in recent years. Nevertheless, we have just visited tens of asteroids while we have discovered more than one million bodies. As

Mission Design of DESTINY+: Toward Active Asteroid (3200) Phaethon and Multiple Small Bodies

“…In the interplanetary transfer phase (IPT), we first design the Earth-Phaethon-Earth trajectory, which is necessary to accomplish the nominal mission, and then extend the trajectory for flybys of multiple small bodies. We assume a zero- radius SOI patched-conics model and employ asteroid flyby cyclers [37,18], a special case of free-return cyclers [38], to solve the IPT trajectory design problem. Free-return cyclers are periodic trajectories that shuttle a spacecraft between two or more celestial bodies, in our case, the Earth and asteroids.…”

“…We store the results as the initial guess if the total ∆V is less than a threshold, which is set to 10km/s in our study. Using the initial guess, we solve the three-phase trajectory optimization problem under the MGA-1DSM model [41,18] and then under the low-thrust model [42]. The objective functions are the total ∆V and the propellant consumption, respectively.…”

“…Also, DESTINY + involves a new challenge to connect the IPT trajectory and the SOR trajectory by the moon flybys. In the IPT, the spacecraft will fly by multiple asteroids utilizing low-thrust maneuvers and Earth gravity assist maneuvers [16,17,18]. NASA's CONTOUR mission [19] has employed multiple Earth gravity assists to visit multiple small bodies.…”

Mission design of DESTINY+: Toward active asteroid (3200) Phaethon and multiple small bodies

“…Also, DESTINY + involves a new challenge to connect the IPT trajectory and the SOR trajectory by the moon flybys. In the IPT, the spacecraft will fly by multiple asteroids utilizing low-thrust maneuvers and Earth gravity assist maneuvers [16,17,18]. NASA's CON-TOUR mission [19] would have employed multiple Earth gravity assists to visit multiple small bodies.…”

“…In the MFB, we generate a Moon flyby trajectory database under a high-fidelity dynamical system, where these are obtained via backward propagation from the escape conditions until crossing the SOI of the Moon. In the IPT, we introduce the trajectory design method of asteroid flyby cyclers [18] to generate initial guess trajectories and then perform low-thrust optimization to translate them to full ephemeris. After discussing of each phase of the mission, the results of the optimized end-to-end low-thrust trajectory under a multi-body dynamical system are shown.…”