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First Results from a Hardware-in-the-Loop Demonstration of Closed-Loop Autonomous Formation Flying

Gill, E. and Naasz, B. and Ebinuma, T. (2003) First Results from a Hardware-in-the-Loop Demonstration of Closed-Loop Autonomous Formation Flying. American Astronautical Society. 26th Annual AAS Guidance and Control Conference, Breckenridge, Co., Feb. 5-9 2003.

Full text not available from this repository.

Abstract

A closed-loop system for the demonstration of autonomous satellite formation flying technologies using hardware-in-the-loop has been developed. Making use of a GPS signal simulator with a dual radio frequency outlet, the system includes two GPS space receivers as well as a powerful onboard navigation processor dedicated to the GPS-based guidance, navigation, and control of a satellite formation in real-time. The closed-loop system allows realistic simulations of autonomous formation flying scenarios, enabling research in the fields of tracking and orbit control strategies for a wide range of applications. The autonomous closed-loop formation acquisition and keeping strategy is based on Lyapunov’s direct control method as applied to the standard set of Keplerian elements. This approach not only assures global and asymptotic stability of the control but also maintains valuable physical insight into the applied control vectors. Furthermore, the approach can account for system uncertainties and effectively avoids a computationally expensive solution of the two point boundary problem, which renders the concept particularly attractive for implementation in onboard processors. A guidance law has been developed which strictly separates the relative from the absolute motion, thus avoiding the numerical integration of a target trajectory in the onboard processor. Moreover, upon using precise kinematic relative GPS solutions, a dynamical modeling or filtering is avoided which provides for an efficient implementation of the process on an onboard processor. A sample formation flying scenario has been created aiming at the autonomous transition of a Low Earth Orbit satellite formation from an initial along-track separation of 800 m to a target distance of 100 m. Assuming a low-thrust actuator which may be accommodated on a small satellite, a typical control accuracy of less than 5 m has been achieved which proves the applicability of autonomous formation flying techniques to formations of satellites as close as 50 m.

Document Type:Conference or Workshop Item (Paper)
Additional Information: LIDO-Berichtsjahr=2003, monograph_id=AAS 03-040,
Title:First Results from a Hardware-in-the-Loop Demonstration of Closed-Loop Autonomous Formation Flying
Authors:
AuthorsInstitution or Email of Authors
Gill, E.UNSPECIFIED
Naasz, B.UNSPECIFIED
Ebinuma, T.UNSPECIFIED
Date:2003
Page Range:pp. 1-16
Publisher:American Astronautical Society
Status:Published
Keywords:Formation Flying; GPS
Event Title:26th Annual AAS Guidance and Control Conference, Breckenridge, Co., Feb. 5-9 2003
Organizer:AAS
HGF - Research field:Aeronautics, Space and Transport (old)
HGF - Program:Space (old)
HGF - Program Themes:W EO - Erdbeobachtung
DLR - Research area:Space
DLR - Program:W EO - Erdbeobachtung
DLR - Research theme (Project):UNSPECIFIED
Location: Oberpfaffenhofen
Institutes and Institutions:Space Operations and Astronaut Training > Hauptabteilung Raumflugbetrieb und Astronautenausbildung
Deposited By: Karin Klier
Deposited On:16 Sep 2005
Last Modified:14 Jan 2010 17:25

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