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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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Committee Members :
Prof. Panagiotis Tsiotras (Advisor)
Prof. Mark Costello
Prof. Marcus J Holzinger
Automatic Mass Balancing System of the 5-DOF Spacecraft Simulator
Spacecraft simulators are widely used to validate spacecraft attitude determination and control techniques. A 5-dof experimental facility at the School of Aerospace Engineering at the Georgia Institute of Technology has been developed to create spacelike environment for academic research and education. This facility is composed of two stages: The upper stage has a hemi-spherical air-bearing that allows frictionless rotational motion of the upper stage and the lower stage has three linear air-bearing pads that make it possible to achieve almost friction-free translational motion of the entire system. In this system, the balancing procedure is a crucial issue that will permit gravitational torques to be diminished into the spacecraft simulator. The aim of this study is to introduce an automatic mass balancing method and eliminate the center of gravity oset from the center of rotation by actuating the three sliding masses, without need of further actuators. Adaptive nonlinear feedback control is proposed in this thesis and the stability and the convergence of the parameters are analyzed through Lyapunov stability theory. The proposed controller will be implemented on the experimental platform to verify the balancing technique.
