Research and Simulation of a Fault Diagnosis and Tolerant Algorithm in Gravity Aided Inertial Navigation System

Considering the structure and characteristics of gravity aided navigation system and federal filter, the paper presents a new algorithm of the fault detection isolation and system reset. The new fault-tolerant algorithm changes the traditional fault judgment to the filtering convergence judgment. Based on this algorithm a new fault diagnosis and tolerant method is established, and the method is verified by the simulation of gravity aided inertial integrated navigation system with the new fault toleration algorithm. Simulation results show that the new fault diagnosis and tolerant algorithm can efficiently restrain the fault of the gravity measurement unit, play the gravity aided navigation subsystem for best results and enhance the system accuracy and fault-tolerant performance.