Abstract:

Magnetorquers and reaction wheels are important control actuators for modern small satellite. The mathematical model for attitude control using magnetorquer and reaction wheel is developed. The necessity to combine magnetorquers and reaction wheels for satellite attitude control in the control algorithm design is analyzed. Using control allocator, a combined control scheme is proposed based on the reaction wheels and magnetorquers to be used. Two control allocation techniques are developed to automatically redistribute the required control torque among reaction wheels and magnetorquers. Numerical simulation demonstrates that the proposed control technique can reduce the opportunity of saturation and the system power consumption without reducing the attitude control accuracy. It can also prolong the life of space task. Other advantages include simple algorithm design, less computation cost and realtime calculation on board.

Key words: control and navigation technology of aerocraft, small satellite, attitude control, reaction wheel, magnetorquer, combined control