Relative Orbits and Control
AdvisorButcher, Eric A.
MetadataShow full item record
PublisherThe University of Arizona.
RightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction, presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
AbstractCooperative control protocols can be formulated for systems comprising multiple independent agents which can share information. In this work I will consider the cooperative control problem for multi-agent systems whose agents obey second-order Newtonian dynamics. Specifically, I will explore consensus and cooperative control laws for arrangements of both free point-mass bodies and point-mass spacecraft in orbit about a celestial body. In the latter case, the linearized equations of motion for two or more bodies in orbit will be used, allowing us to frame cooperative control laws in the standard formalism of algebraic graph theory. One of the primary novelties explored in this work is the usage of non-integer order integral and derivative operators in the feedback controllers for cooperative multiagent systems. These fractional operators provide additional degrees of freedom in controller design, and therefore afford more freedom in shaping the controlled system’s trajectories. Among the main results presented in this work, we prove the stability of certain fractional consensus controllers and show that these controllers can outperform standard integer-order controllers in terms of some important performance measures.
Degree ProgramGraduate College
Degree GrantorUniversity of Arizona
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