Method for controlling the attitude of an satellites in elliptic orbits using solar radiation pressure

摘要

The present invention provides a method for the attitude control of satellites in elliptic orbits or satellites initially placed in circular orbits perturbed to elliptic orbits due to environmental disturbances. The method relies on the application of solar radiation pressure to provide the desired torque for the satellite attitude control. The satellite is equipped with two-oppositely placed light-weight solar panels extending away from the satellite along a predetermined direction (satellite body fixed Y-axis). By rotating one of these solar panels or both of them through desired angles about their axis using the respective driver motors as per the simple open-loop control law, the torque about the satellite axis is developed to achieve the desired attitude performance. The open-loop control law is derived using an analytical approach to neutralize the excitation caused by eccentricity and it is implemented via analog logic based on the information of sun angle and satellite position provided by the sensors. The present invention significantly improves the performance of the satellite by a factor of more than 20 times approximately in general and it only requires the rotation of the solar panels by fraction of a degree for particular system parameters. Thus, the semi-passive nature of the present invention makes it attractive for future space applications.