Near Real-Time Closed-Loop Optimal Control Feedback for Spacecraft Attitude Maneuvers

<p>Optimization of spacecraft attitude maneuvers can significantly reduce attitude control system size and mass and extend satellite end-of-life. Optimal control theory has been applied to solve a variety of open-loop optimal control problems for terrestrial air and space applications. However general application of real-time optimal controllers on spacecraft for large slew maneuvers has been limited because open-loop control systems are inherently vulnerable to error and the computation necessary to solve for an optimized control solution is resource intensive. This research effort is focused on developing a near real-time optimal control (RTOC) system for spacecraft attitude maneuvers on the Air Force Institute of Technology's 2nd generation simulated satellite SimSat II. To meet the end goal of developing a RTOC controller necessary preliminary steps were completed to accurately characterize SimSAT II's mass properties and attitude control system. Using DIDO a pseudospectralbased optimal control solver package to continuously solve and execute a sequence of optimized open-loop control solutions in near real-time the RTOC controller can optimally control the state of the satellite over the course of a large angle slew maneuver. In this research simulation and experimental results clearly demonstrate the benefit of RTOC versus other non-optimal control methods for the same maneuver.</p><p>This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact and remains as true to the original work as possible. Therefore you will see the original copyright references library stamps (as most of these works have been housed in our most important libraries around the world) and other notations in the work.</p><p>This work is in the public domain in the United States of America and possibly other nations. Within the United States you may freely copy and distribute this work as no entity (individual or corporate) has a copyright on the body of the work.</p><p>As a reproduction of a historical artifact this work may contain missing or blurred pages poor pictures errant marks etc. Scholars believe and we concur that this work is important enough to be preserved reproduced and made generally available to the public. We appreciate your support of the preservation process and thank you for being an important part of keeping this knowledge alive and relevant.</p><br>