A Method Research on Robust Fault Diagnosis of Integrated Navigation Systems

Optimal parity-vector test (OPT) approach was applied to the fault diagnosis of the integrated navigation systems. According to robust design principle, the optimal parity vectors, be most sensitive to designated sensor´s fault and least sensitive to other sensor´s fault and unknown in-puts such as noises, were designed and the optimal parity residuals were obtained. According to matrix theory, the fault detection and fault isolation functions were constructed, respectively. Many Monte-Carlo simulations were performed in three navigation systems by using the presented method and the general fault diagnosis method , respectively, and the results show the proposed method, compared with the general diagnosis method, can increase the fault isolation rate obviously for navigation systems who have greater measurement noise. This proposed method depends only on the measurement data of every navigation sensor not on their dynamic models and can be applied to the fault of other redundant sensor systems.