Closed-loop control of spacecraft formations with applications on SPHERES

Formation flying satellites offer potentially greater science returns and operational capabilities than attainable with a monolithic spacecraft. Successful control of a formation of spacecraft can be divided into two separate stages. The first stage creates a plan that meets a set of mission objectives, and the second stage implements the plan. Plans are specified as a sequence of [delta]V commands executed at specific times during an orbit. This thesis presents an online method for generating fleet-wide plans, using convex optimization techniques, that satisfy multiple objectives. The approach allows for minimum and balanced fuel usage, can position spacecraft in arbitrary configurations, and favors low-maintenance orbits that do not drift apart. Additionally, the architecture is applicable not only to formation-keeping maneuvers, but also to formation reconfigurations. Various simulations demonstrate the importance of accurately implementing plans for formation flying as well as autonomous rendezvous and docking missions. Specifically, the relationships between process error, overall fuel use, and position error are studied. Theory is put into practice with the development of a new low-level, closed-loop thrust controller for the Synchronized Position Hold Engage and Reorient Experimental Satellites (SPHERES). The controller processes measurements from accelerometers and gyroscopes to monitor thruster performance in real-time. Experiments conducted on the International Space Station (ISS) validate the controller and establish a foundation for future enhancements to the underlying algorithm. Finally, data from a series of high-fidelity formation flying simulations is presented that confirms the analysis done elsewhere in the thesis.

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

• Jeffrey, Matthew M

Advisor dc:contributor.advisor

• Jonathan P. How.

• 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/1721.1/45219

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/45219