Dynamic Modeling for Earth – Pointing Satellites to Control the Three – axis Attitude without the Attitude Information of One Axis

Various methods are presented to control the attitude of satellite due to lack of information of yaw axis attitude so far. In this paper, a new method is used which is more general and is applicable to all types of satellites, with at least one controller. This method is not limited to YAW axis and can control the two other axes as well. One feature of this approach is the ability to be modified for large angle maneuvers for special applications. A new observer is also proposed for the controller, which causes the angles attitude to be kept in desirable values, with minimum control effort and more accuracy. Simulation results show that compare with methods using the complete all axis information, this approach is satisfactory. Keywords: Attitude control, PID controlley, BIBO stability, pseudo observer