摘要 |
<p>An apparatus and method for orbit control and maintenance techniques for both individual satellites and for multiple satellites in a constellation utilizing Modern Feedback Control for providing precise autonomous on-board navigation and control. This control system can place any satellite in any orbit position in a constellation, including the acquisition of the initial distribution for the constellation after satellite separation from launched vehicles. This system can also maintain distribution within a constellation, including station relocation and station keeping. Utilizing GPS position information, the orbit state vector is determined and modern advanced multivariable feedback control techniques, for example, linear quadratic Gaussian/loop transfer recovery controllers or optimal H-Infinity Robust Controllers are used to design a navigation and control system. The present invention uses a feedback control system designed to attenuate the external perturbations and provide robustness against unstructured uncertainty. The control problem is converted into first a tracking problem and a regulator design problem where the control problem is to minimize both position error and velocity error between the satellite (pursuer) and a nonexistent target satellite in an ideal orbit. The elimination of position error and velocity error result in an optimal orbital control system.</p> |