Abstract AAS 97-723

AAS 97-723

FLEXIBLE SPACECRAFT REORIENTATIONS USING GIMBALED MOMENTUM WHEELS

K.A. Ford and C.D. Hall - A.F. Institute of Technology/ENY

Abstract

We study the reorientations of flexible spacecraft using momentum wheels and control moment gyros. A new concise form of the equations of motion for a spacecraft with CMGs is presented using gimbal torques as control inputs. Feedback control laws which result in smooth reorientations are sought with the goal of minimizing structural excitations. We pay special attention to a class of maneuvers wherein the magnitude of the momentum in the wheel cluster is held constant, resulting in a so-called 'stationary platform maneuver.' The advantage of this maneuver is that the platform angular velocity remains small throughout.