Innovation Approach Based Sensor FDI in LEO Satellite Attitude Determination and Control System

Abstract

In this study Fault Detection and Isolation (FDI) in the attitude determination and control system of Low Earth Orbit (LEO) satellite is investigated. Attitude determination system uses algebraic method. This method is based on computing any two analytical vectors in the reference frame and measuring these vectors in the body coordinate system (Barishev & Krilov, 1968; Wertz, 1988). As measuring devices, magnetometers and sun sensors are used. The satellite attitude is estimated via Extended Kalman Filter (EKF). The Kalman filter approach to attitude determination and control is quite sensitive to the any measurement malfunctions (abnormal measurements, sudden shifts in the measurement channel, and other difficulties such as decrease of instrument accuracy, an increase of background noise, etc.). If the condition of operation of the measurement system does not correspond to the models, used in the synthesis of filter, then these changes resulting from some possible failures at the measurement channels significantly decrease the