Magnetic attitude control and periodic motion for the in-orbit rotation of a dual-spin satellite (original) (raw)

Motion of a satellite equipped with a pitch flywheel and magnetic coils in gravitational field

Cosmic Research, 2017

A satellite equipped with a magnetic attitude control system and a pitch flywheel has been considered. The system performance in the transient mode has been investigated. The characteristic exponent of the system have been approximated for a satellite on a circumpolar orbit. In the steady-state mode of gravitational attitude, small motions are considered in the vicinity of equilibrium. The attitude accuracy has been analyzed. The algorithm of an arbitrary but given attitude of the satellite in the orbital plane has been investigated. A numerical simulation has been performed.

Comparison of two magnetic damping laws for the attitude acquisition of a dual spin satellite

International Journal of Space Science and Engineering, 2019

Dual spin satellite motion in the attitude acquisition phase is considered. Starting from the arbitrary rotation state, the satellite should end up with its angular momentum aligned with the orbit normal. The satellite is equipped with magnetorquers that provide the angular velocity damping. Two control strategies are compared, that is the simple exponential damping and "weighted" damping arising from the classical sliding control implementation. The time response of the control system depending on the satellite inertia moments is analyzed. Simple damping is proven to provide better results for the low control authority even for the significantly elongated satellite. This result is proved with the analytical solution for the characteristic exponents approximations. Weighted damping is shown to provide better results for significant control authority through numerical simulation.

Terminal One Axis Stabilization Properties of a Spinning Satellite Employing Simple Magnetic Attitude Control

Mathematics, 2023

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.

Single axis stabilization of a fast rotating satellite in the orbital frame using magnetorquers and a rotor

Acta Astronautica, 2020

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.

Passive magnetic stabilization of the rotational motion of the satellite in its inclined orbit

Applied Mathematical Sciences, 2015

The problem of perturbed rotational motion of the satellite is one of the most interesting, important and, at the same time, mathematically complex problems of celestial mechanics and space flight dynamics. Among existing stabilization systems, a passive magnetic stabilization systems have a special place, since they have an exceptional reliability and are easy to manufacture. In this paper the problem of passive magnetic stabilization of the rotational motion of the satellite is studied. It is assumed that passive magnetic system provides its orientation along the vector of the geomagnetic field strength H. The geomagnetic field is simulated by the direct dipole model, considering different orbits of inclination. In the considered model an effect of the gravitational torque is taken into account. Results of computational experiments are presented.

Spin-Stabilized Spacecrafts: Analytical Attitude Propagation Using Magnetic Torques

Mathematical Problems in Engineering, 2009

An analytical approach for spin-stabilized satellites attitude propagation is presented, considering the influence of the residual magnetic torque and eddy currents torque. It is assumed two approaches to examine the influence of external torques acting during the motion of the satellite, with the Earth's magnetic field described by the quadripole model. In the first approach is included only the residual magnetic torque in the motion equations, with the satellites in circular or elliptical orbit. In the second approach only the eddy currents torque is analyzed, with the satellite in circular orbit. The inclusion of these torques on the dynamic equations of spin stabilized satellites yields the conditions to derive an analytical solution. The solutions show that residual torque does not affect the spin velocity magnitude, contributing only for the precession and the drift of the spacecraft's spin axis and the eddy currents torque causes an exponential decay of the angular velocity magnitude. Numerical simulations performed with data of the Brazilian Satellites SCD1 and SCD2 show the period that analytical solution can be used to the attitude propagation, within the dispersion range of the attitude determination system performance

Analytical Prediction of the Spin Stabilized Satellite's Attitude Using The Solar Radiation Torque

Journal of Physics: Conference Series

The aim of this paper is to present an analytical solution for the spin motion equations of spin-stabilized satellite considering only the influence of solar radiation torque. The theory uses a cylindrical satellite on a circular orbit and considers that the satellite is always illuminated. The average components of this torque were determined over an orbital period. These components are substituted in the spin motion equations in order to get an analytical solution for the right ascension and declination of the satellite spin axis. The time evolution for the pointing deviation of the spin axis was also analyzed. These solutions were numerically implemented and compared with real data of the Brazilian Satellite of Data Collection-SCD1 an SCD2. The results show that the theory has consistency and can be applied to predict the spin motion of spin-stabilized artificial satellites.

Spin-stabilized satellite magnetic attitude control scheme without initial detumbling

Acta Astronautica, 2014

The angular motion of an axisymmetrical satellite equipped with an active magnetic attitude control system is considered. The dynamics of the satellite are analytically studied on the whole control loop. The control loop is as follows: preliminary reorientation along with nutation damping, spinning about the axis of symmetry, then precise reorientation of the axis of symmetry in inertial space. Reorientation starts right after separation from the launch vehicle. Active magnetic attitude control system time-response with respect to its parameters is analyzed. It is proven that low-inclined orbit forces low control system time-response. Comparison with the common control scheme shows the time-response gain. Numerical analysis of the disturbances effect is carried out and good pointing accuracy is proved.

Numerical and analytical approach for the spin-stabilized satellite attitude propagation

Computational and Applied Mathematics

This paper presents the comparison between the numerical and analytical results of a spacecraft attitude propagation for a spin-stabilized satellite. Some external torques are introduced in the equations of the motion and the comparisons are done considering that these torques are acting together, which are: gravity gradient, aerodynamic, solar radiation, magnetic residual and eddy current. In the numerical approach it is used the quaternion to represent the attitude. This numerical approach can be applied for any kind of satellite. The analytical approach is applied directly for a spin-stabilized satellite and the equations of motion are described in terms of the spin velocity, spin axis right ascension and declination angles. An analytical solution of these equations is presented and valid for one orbit period. Applications are developed considering the Brazilian spin-stabilized satellites SCD1 and SCD2. The comparisons are important to validate some simplifications that are required in