Optimal Libration Point Orbital Maneuvers
- Paper number
IAC-05-C1.1.09
- Author
Dr. Paul Williams, Australia
- Coauthor
Ms. Olga Trivailo, Monash University, Australia
- Year
2005
- Abstract
This paper studies the control of a spacecraft in the vicinity of the Sun-Earth libration points. In particular, we study optimal orbit transfers from Earth orbit into halo orbit at the L1 point, and also consider the design of a controlled halo orbit itself. Furthermore, the design of three-dimensional periodic orbits at the triangular libration points is also undertaken. These types of orbits have many important and useful applications, as has been demonstrated recently by the Genesis mission, which employed a halo orbit at the L1 point in the Sun-Earth system. Minimum fuel trajectories are determined by solving a nonlinear programming problem which parameterizes the continuous problem into a discrete parameter optimization problem. This process is automated in a MATLAB-based package called DIRECT. Periodic orbits are determined within the same framework by constraining the initial position and velocity of the spacecraft to be equal to the final position and velocity (both of which are free), and allowing the period to be free. Controlled periodic orbits are determined for the Sun-Earth libration points, such as L1/L2 and L4/L5, as well as some other points in the same system. For certain initial guesses and constraints, globally optimal solutions (i.e., zero thrust/fuel) periodic orbits have been determined. The effect of lunar perturbations on the optimal controlled periodic orbits is also determined within the context of a restricted four-body problem. We are able to effectively demonstrate the unification of the design of spacecraft orbits and optimal control using a fully nonlinear model of the spacecraft dynamics.
- Abstract document
- Manuscript document
IAC-05-C1.1.09.pdf (🔒 authorized access only).
To get the manuscript, please contact IAF Secretariat.