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The escalating proliferation of space debris poses an increasing risk to spinning satellites, elevating the probability of hazardous collisions that can result in severe damage or total loss of functionality. To address this concern, a pioneering inflatable protective structure is employed to ensure the optimal functionality of spinning satellites. Additionally, a multi-body dynamic modeling method based on spring hinge unfolding/spring expansion is proposed to tackle the complex dynamics of spinning satellites with inflatable protective structures during flight. This method enables analysis of the motion parameters of spinning satellites. First, the structural composition of a spinning satellite with inflatable protective structures is introduced and its flight process is analyzed. Then, an articulated spring hinge unfolding model or a spring expansion model using the Newton–Euler method is established to describe the unfolding or expansion of the spinning satellite with inflatable protective structures during flight. Finally, the effects on the motion parameters of a spinning satellite are analyzed through simulation under various working conditions. [ABSTRACT FROM AUTHOR]

A spin stabilized satellite reorientation maneuver in the inertial space is investigated. Spin axis pointing and nutation damping magnetic attitude control algorithms are utilized. Evolutionary equations for the oscillations of a symmetrical satellite near the required position are derived. The exact solution for the wobble amplitude is obtained for the averaged equations of motion. Spin axis attitude angles relative to the required direction are analyzed. Optimal control gain is found for the reorientation maneuver. Theoretical results are verified with numerical simulation. [ABSTRACT FROM AUTHOR]

The escalating proliferation of space debris poses an increasing risk to spinning satellites, elevating the probability of hazardous collisions that can result in severe damage or total loss of functionality. To address this concern, a pioneering inflatable protective structure is employed to ensure the optimal functionality of spinning satellites. Additionally, a multi-body dynamic modeling method based on spring hinge unfolding/spring expansion is proposed to tackle the complex dynamics of spinning satellites with inflatable protective structures during flight. This method enables analysis of the motion parameters of spinning satellites. First, the structural composition of a spinning satellite with inflatable protective structures is introduced and its flight process is analyzed. Then, an articulated spring hinge unfolding model or a spring expansion model using the Newton–Euler method is established to describe the unfolding or expansion of the spinning satellite with inflatable protective structures during flight. Finally, the effects on the motion parameters of a spinning satellite are analyzed through simulation under various working conditions.

Satellite angular motion under the action of the Sdot one-axis magnetic control algorithm is analyzed. Sdot control stabilizes the maximum moment of inertia axis towards the Sun. Evolutionary equations that avoid singularity in the required position are derived. Linearization of equations is performed and new variables that describe the maximum moment of inertia axis oscillations amplitudes are introduced. The resulting equations are suitable for the averaging method application. Evolutionary equations for slow variables are solved. Simplified evolutionary expressions are verified with numerical simulation. [ABSTRACT FROM AUTHOR]

A spin stabilized satellite reorientation maneuver in the inertial space is investigated. Spin axis pointing and nutation damping magnetic attitude control algorithms are utilized. Evolutionary equations for the oscillations of a symmetrical satellite near the required position are derived. The exact solution for the wobble amplitude is obtained for the averaged equations of motion. Spin axis attitude angles relative to the required direction are analyzed. Optimal control gain is found for the reorientation maneuver. Theoretical results are verified with numerical simulation.

Satellite angular motion under the action of the Sdot one-axis magnetic control algorithm is analyzed. Sdot control stabilizes the maximum moment of inertia axis towards the Sun. Evolutionary equations that avoid singularity in the required position are derived. Linearization of equations is performed and new variables that describe the maximum moment of inertia axis oscillations amplitudes are introduced. The resulting equations are suitable for the averaging method application. Evolutionary equations for slow variables are solved. Simplified evolutionary expressions are verified with numerical simulation.

Fast rotating satellite with a rotor is considered. Overall angular momentum of the satellite-rotor system is small. Satellite rotation rate is determined by the rotor angular momentum. This momentum is constant in the nominal attitude mode. Magnetic control system is used to ensure the total angular momentum convergence to zero and spin axis stabilization along the satellite velocity on a circular orbit. Control dipole moment is proposed to provide the necessary equilibrium position. Control torque that resembles the damping law is developed to provide the asymptotic stability. Issues of the control implementation by the magnetic system are considered. • Fast rotating satellite with a rotor is considered. • Spin axis is directed along the satellite orbital velocity. • Satellite-rotor system angular momentum is small. • Magnetorquers provide the rotation and attitude maintenance. [ABSTRACT FROM AUTHOR]

This work is an investigation on the roots of chaotic attitudinal motion in a class of asymmetrical gyrostat satellites. The result shows that for a class of Kelvin type gyrostat satellite, there is an equivalent rigid spinning satellite with the same attitude dynamics. Finding some constants of motion and eliminating the cyclic coordinates, the rotational kinetic energy is changed to a quadratic form and using Jordan canonical form of the associated inertia tensor and transforming the coordinate system, the Hamiltonian has been changed to those of a rigid satellite. The Hamiltonian has been split into integrable and non-integrable parts. Using Deprit canonical transformation and Andoyer variables the integrable part has been reduced to a one-dimensional form. The reduced Hamiltonian shows that the regular dynamics of the satellite can be chaotic, under the influence of gravitational effects. To demonstrate various attitudinal dynamics of the satellite, a second-order Poincare´ map is employed. This research shows firstly, that the attitudinal dynamics of Kelvin type gyrostat satellites and rigid satellites follow the same dynamical patterns, secondly, for non-linear analysis of dynamics of gyrostat satellite based on the perturbation methods, there is a preferable form for Hamiltonian of the system in the near-integrable fashion and thirdly the chaotic motion is originated from the gravitational field effects that can be suppressed by increasing the attitudinal energy of the satellite in comparison with the translational energy. [Copyright &y& Elsevier]