Aerodynamic Attitude Control of Ultra-low Earth Orbit Satellite

This paper describes a method for active attitude control using only aerodynamic torque in ultra-low orbit. A satellite with four panels is studied and the simplified method for calculating aerodynamic torque of each panel is proposed based on rarefied gas dynamics. The approximate linear relationship between aerodynamic torque and panel rotation angle is obtained by integrating four panels. According to the desired control torque, an algorithm for calculation of expected panel rotation angle is proposed based on the linear equations. Then the actual aerodynamic torque is obtained in the accurate aerodynamic model, which provide aerodynamic control torque instead of the traditional actuator. The case of adjusting from an initial attitude angle to zero attitude angle is simulated, in which only the panels are used as the actuator. Considering the interference of environmental torque and measurement error, the satellite is controlled to the desired attitude, which shows that this method is feasible and has good anti-interference ability.