Publication: Roll and yaw actuation for momentum biased satellite by magnetic torquers
Date
2009-04-01
Authors
Chong, Chia Ye
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The control of the satellite attitude is very important because for certain satellite, they need to fix to a point throughout their operation. The tolerance on the attitude errors are small, so we need to choose a control technique to be used on the satellite. Several control methods have been developed since the first satellite was launched, and the control techniques can be classified as active or passive. Active techniques are needed for missions where high pointing accuracy is crucial but very expensive. Magnetic technique is attractive for controlling small satellites in Low Earth Orbits (LEO). Magnetic control systems are relatively lightweight, require low power consumption and inexpensive compared to the other control methods. In this thesis, the magnetic torque rods have been selected as the actuator to control the satellite attitude. This is due its characteristic which can generate magnetic dipole moment thus creating torque when interact with the earth magnetic field. The simulation work has been carried out by Matlab 7.0. Performances from simulations show that the attitude steady-state error is achieved within two orbital periods with values of 0.3 and comply with the mission requirement. Controllers are structured using ordinary PD (Proportional Derivative) controller to control roll and yaw axis of a small momentum biased satellite in nominal attitude operation.