Fault-Tolerant Filtering Algorithm for SINS/BDS Tightly-coupled Integrated Navigation System

The effective fault diagnosis is the basis of system reliability and accuracy in SINS/BDS tightly-coupled integrated navigation system. The state equation and measurement equation in the launch inertial frame are modeled. A fault-tolerant Kalman filtering algorithm is proposed, the improved chi-square test method is designed to realize the detection and screening of BDS measurement fault. The simulation results illustrate that the fault-tolerant Kalman filter can effectively detect faults, the velocity error and the position error are controlled within 0.3m/s and 20m repectively.