System characterization and online mass property identification of the SPHERES formation flight testbed

The National Aeronautics and Space Administration (NASA) and other entities in the aerospace industry have recently been considering distributed architectures for many space applications, such as space-based interferometry. Whether the craft in such a system are structurally connected or flown in tight formation, distribution allows for higher redundancy in case of failures as well as reducing the minimum payload footprint for launch. Designed to fly in precise formation, the SPHERES satellites rely on accurate system characteristics such as thruster strength and vehicle mass and inertia. The SPHERES testbed is described and the applications for formation flight are presented. Mass properties of the SPHERES satellites are examined because of their impact on control determination, with comparison between CAD model estimates and empirically determined values. The sensor and actuator suite, essential for closed-loop control, are also identified and characterized. A recursive least squares algorithm for determining mass properties in real time is explained and implemented both offline and online with results from test flights aboard NASA's KC-135 micro-gravity aircraft (Reduced Gravity Airplane, RGA).

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Aeronautics and Astronautics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2008

Author dc:creator

• Berkovitz, Dustin S. (Dustin Scott)

Advisor dc:contributor.advisor

• David W. Miller.

• Aeronautics and Astronautics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/43083

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/43083