An approach for fault detection and identification in PL/INS navigation system

A method for multiple faults identification of PL (pseudo-satellite)/INS (inertial navigation system) tightly coupled navigation system based on fuzzy logic was presented. The failure associated with PL was analyzed, and fuzzy parity equations were used to detect, isolate and identify PL failure modes. First of all, the PL/INS tightly coupled navigation system was described by the Takagi-Sugeno (T-S) fuzzy model, and then full decoupled parity equations were applied to the local linearised models. The faults can be detected and isolated by the sum of the local residuals and Kalman filter algorithm was used for identifying the fault parameters. Besides, the necessary conditions for parameter identification was bring forward. The simulation results show that, in case of multiple signal faults in PL simultaneously, this method can effectively detect them and precisely identify the parameters of failure modes.