Research on attitude determination of micro-satellite with impact of remanence

The performance of attitude determination and control system using sun-sensor/magnetometer/gyro as attitude sensors would be impacted by the remanence of micro-satellite. To reduce the influences of remanence, a two-step Extended Kalman Filter (EKF) method is developed to estimate the steady magnetometer bias and residual magnetic moment. Firstly, the magnetometer bias is estimated. Then the magnetometer is calibrated with the estimation of magnetometer bias, and the corrected measurement is employed to estimate the attitude as well as the residual magnetic moment. Simulation results indicate that the accuracy of attitude determination is about 1° and the accuracy of magnetometer bias and magnetic moment estimation is about 10nT and 0.03A•m2. The impact of remanence can be observably eliminated via the two-step EKF method.