A Shape-Based Approach For Low-Thrust Earth-Moon Trajectories Initial Design.

Area of Science:

• Aerospace Engineering
• Astrodynamics
• Applied Mathematics

Background:

• Generating efficient Earth-Moon trajectories is crucial for space missions.
• Continuous low-thrust propulsion presents unique trajectory design challenges.
• Leveraging three-body dynamics can reduce propellant requirements.

Purpose of the Study:

• To develop a fast and robust method for generating 3D Earth-Moon trajectories using continuous low thrust.
• To design trajectories that satisfy equations of motion and boundary conditions efficiently.
• To enable significant plane changes without primary propulsion.

Main Methods:

• Approximation of position vector components using finite Fourier series.
• Optimization of a thrust-free phase near the L1 Lagrange point for plane change.
• Development of an analytic approximation for initial guess generation in escape and capture phases.
• Leveraging three-body problem characteristics for propulsion-free plane change.

Main Results:

• The Robust Finite Fourier Series (R-FFS) method successfully generates 3D trajectories for various lunar missions.
• The approach meets constraints on maximum engine thrust levels.
• Demonstrated ability to achieve required plane changes in thrust-free phases.
• Efficient generation of trajectories to high lunar orbits, low lunar orbits, and Halo orbits.

Conclusions:

• The R-FFS approach provides a computationally efficient and robust solution for low-thrust Earth-Moon trajectory design.
• The method's ability to perform plane changes without propulsion significantly enhances mission efficiency.
• This technique is suitable for generating complex 3D transfers to diverse lunar orbits.