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Occasion: Master’s Thesis Defense
Student: John Matthew Brewer
Advisor: Panagiotis Tsiotras
Title: Partial Attitude Synchronization of Underactuated Satellite Systems
Time: 12pm on December 5th
Location: Montgomery-Knight Bldg, Room 317
Abstract:
Numerous works have investigated problems concerning the complete attitude consensus of multi-spacecraft systems as well as the attitude control of an underactuated spacecraft, where only two or fewer control torques are available. There have been, however, no works which have focused on the attitude consensus problem among multiple underactuated spacecraft successfully, to the author's knowledge.
In this thesis, three control laws are presented to solve three problems concerning this rather underdeveloped area. In the first problem, the aim is to achieve partial attitude consensus amongst a network of underactuated spacecraft in which the uncontrolled axis of each satellite points in the same fixed inertial direction. In the second problem, the aim is to solve a similar system, where the pointing direction of the uncontrolled axes is no longer constrained to point along a fixed direction and instead may rotate in inertial space. The third problem is an extension of the first problem where the leaderless system is expanded to that of a leader-follower type so that the intended final pointing direction of the uncontrolled axes of the spacecraft may be specified. Utilizing a novel attitude parameterization, the control laws are able to take the form of a linear controller for the first problem, its extension, and for the second problem if the satellites are axisymmetric. As a result of the three control laws, the desired partial attitude consensus state becomes almost globally asymptotically stable.
Committee Members:
