Combination of fault tolerant controller and gyro bias observer in satellite attitude determination system

In this study, we designed a fault tolerant controller for satellite attitude determination control system (ADCS) by combination an adaptive-sliding mode controller and gyro bias estimator. The observer estimates quaternion and bias error and then by using satellite kinematics equation, produces real velocity of satellite. The proposed method could tolerate disturbances in space and also dynamic uncertainty up to 30% and omit gyro bias error completely. Stability of combined controller and observer proved by Lyapunov stability.