meetings - Space Flight Mechanics Committee

coordinates are advantageous because the solution to the unperturbed differential equations
is that of a linear harmonic oscillator, so the analytical solution is explicitly characterized.
The control scheme progresses through thrust-coast regimes covering two phases: first, a
matching of the target's semi-major axis, and second, a matching of position and velocity of
the target. The control algorithm is robust, computationally fast, and can be used for both
low- and high- thrust problems.
16:15 AAS Formation Flying near the Libration Points by Impulse Control
13-397 Mai Bando, Kyushu University; Akira Ichikawa, Nanzan University
In this paper halo orbits near a collinear libration point are considered, and the maintenance
problem by impulsive feedback is considered. For this purpose the equations of motion are
expressed by the rotating framework whose origin is the libration point. This makes the
dynamics semilinear, and the linear control theory can be employed. For the follower's orbit
periodic perturbations of the halo orbit are used. To maintain such an orbit, the output
regulation thoery for linear systems is used. Stabilizing feedback controls are designed via
the algebraic Riccati equations of the linear quadratic regulator (LQR) for discrete-time
system.
16:35 AAS Study of Elliptical Relative Motion Control Based on Relative Orbit Elements
13-474 Jianfeng Yin, Beihang University; Chao Han, Beihang University
A new impulsive feedback control law is developed for the elliptical relative motion based
on relative orbit elements (ROE). The control of the in-plane and out-of-plane relative
motions can be completely decoupled using the new method, which are suitable for both
elliptical and circular reference orbits. The ROE-based control method needs four thrusts to
achieve the elliptical relative motion control. Two different impulsive in-plane control
methods are proposed. Different typical orbit maneuvers, including formation
establishment, reconfiguration, long-distance maneuver and formation keeping are
simulated to demonstrate the performance of the proposed ROE-based control laws.
23 rd AAS / AIAA Space Flight Mechanics Meeting Page 81