Hysteresis dampers are commonly used in Passive magnetic Attitude Control System (PACS). In PACS these rods produce a damping torque and reduce the satellite angular momentum and angular velocity. In this paper, a spin satellite was investigated which utilizes a passive magnetic damper consisting of magnetic hysteresis rods aligned with principal axis or spin axis of satellite and de-tumbling o...

We provide stabilizing feedback control laws for the kinematic system of an underactuated axisymmetric spacecraft subject to input constraints. The proposed control law forces all closed-loop trajectories in a region of the state space where the control inputs are small and bounded. The control law is subsequently extended to solve the case of attitude tracking for an underactuated spacecraft u...

The orientation of a satellite in space described relative to some other object or system is known as the attitude of the satellite. The attitude may be changing with time. To be able to control the attitude of the satellite, it must be equipped with actuators that can produce the required torque. Control Moment Gyroscope is a space craft control actuator which acts as torque amplifier. It is s...

For many years, the importance of active feedback control of large space structure (LSS) have been widely recognized. This paper presents results on studying the attitude control problem for an LSS typified by the ETSVI (Engineering Test Satellite-VI) spececraft. The attitude control system based on the statefeedback control is proposed. The control law is designed by using the turn over design...

It is well known that complete attitude control of a spacecraft is not possible with only one single-gimbal Variable-Speed Control Moment Gyro (VSCMG) due to the conservation of the angular momentum. However, partial attitude control without violating the angular momentum conservation principle is still possible. In this paper, feedback controllers that stabilize the angular velocity vector of ...

The research presented in this report focuses on the Whorl II spacecraft simulator in Virginia Tech’s Space Systems Simulation Laboratory (SSSL). The goal of this research is to improve the reliability and accuracy of the magnetometer aboard Whorl II that is used for attitude determination. Magnetic interference surrounding the simulator causes unacceptable margins of error its perceived attitu...

The theoretical challenge involved in the operation of VTOL UAVs is often divided into two main problems. The first problem involves the development of an estimation scheme which can accurately recover the orientation, or angular position, of the aircraft. The second problem involves the development of algorithms which can be used to reliably control the orientation and/or the position of the v...

In the dual-axis rotation inertial navigation system (INS), besides the gyro error, accelerometer error, rolling misalignment angle error, and the gimbal angle error, the shaft swing angle and the axis non-orthogonal angle also affect the attitude accuracy. Through the analysis of the structure, we can see that the shaft swing angle and axis non-orthogonal angle will produce coning errors which...