Fault diagnosis for attitude sensors via a bank of extended Kalman filters

This paper proposes a new fault detection and isolation method for the spacecraft attitude sensors by integrating the dedicated observer scheme (DOS) and extended Kalman filter (EKF). In this paper, the attitude sensors are arranged into several groups and then a bank of EKFs are designed to estimate the attitude. Using the attitude estimates provided by the EKFs, a fault detection and isolation strategy is constructed based on the methodology of DOS. The main contribution of this paper lies in that the proposed method not only considers the faults in the gyroscopes but also can deal with those in the star sensor. Moreover, the biases in the gyroscopes are considered in the design of EKF so as to ensure the accuracy of the proposed method. Finally, simulation results are given to demonstrate the performance of the proposed method.