Small-Satellite Magnetorquer Attitude Control System Modelling and Simulation

The field of Ocean Robotics Engineering is expanding rapidly and there is demand for low cost, compact and light-weight small-satellites to communicate with remote ocean bound devices. This paper discusses the work carried out with the school's microsatellite group and focusses on the attitude control system which is vital for accurate satellite operation. Establishing a mathematical model for micro-satellite attitude control system contains positioning sensors system, kinematic and dynamic concept of the attitude and statistic processing methods and so on. In this dissertation, based on the Euler angle and Quaternion principles, we built the attitude kinematic model. By considering the magnetometers data and Fuzzy Control method the attitude estimation, was studied and investigated. The paper would also provide a brief investigation towards the modes of attitude control process and analysis. The result of unloading of a momentum wheel by magnetic rotation and precession damping is studied using Simulink. The control system model is included with relationship of three-axis motion simulation, to determine the pitch-channel and roll-yaw channel respectively. This process would define the stability controller problem of wheel unloading and protected mode for small-satellite stabilization.