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Attitude motion reconstruction of the Technological NanoSatellite TNS-0 #2 during the last month of its mission is presented in the paper. The satellite was designed to test the performance of the data transmission via the Globalstar communication system. This system successfully provided telemetry (even during its atmosphere re-entry) up to an altitude of 156 km. Satellite attitude data for this phase is analyzed in the paper. The nominal satellite attitude represents its passive stabilization along a geomagnetic field induction vector. The satellite was equipped with a permanent magnet and hysteresis dampers. The permanent magnet axis tracked the local geomagnetic field direction with an accuracy of about 15 degrees for almost two years of the mission. Rapid altitude decay during the last month of operation resulted in the transition from the magnetic stabilization to the aerodynamic stabilization of the satellite. The details of the initial tumbling motion after the launch, magnetic stabilization, transition phase prior to the aerodynamic stabilization, and subsequent satellite motion in the aerodynamic stabilization mode are presented. [ABSTRACT FROM AUTHOR]

In this paper, the study of stabilization accuracy of a satellite equipped with a set of reaction wheels (RW) is presented. The model of motion takes into account possible static and dynamic reaction wheel imbalances. Due to the complexity of the model, which leads to the numerical issues, the effects of dynamic and static imbalances on inertial stabilization are studied analytically. As a result, estimations of the attitude and stabilization accuracy are presented in closed form. [ABSTRACT FROM AUTHOR]

The problem of large angle slew maneuvers under the attitude restrictions is considered. The modification of the single axis Lyapunov feedback attitude control is proposed. It "locally" changes the standard attitude controller to accommodate the attitude restrictions avoidance. The problem of the unwanted equilibria appearance is thoroughly investigated. Different keep-out zones intersection cases are considered. • Single axis attitude controller that ensures the necessary motion of one satellite axis is presented. • Its modification that allows taking into account the presence of the keep-out zones is suggested. • The problem of additional equilibria appearance is studied in details. [ABSTRACT FROM AUTHOR]