Research on Fault-Tolerant Full Attitude Measuring for Sins with Skewed Redundant Instruments

摘要

The reliability of the strapdown inertial navigation system (SINS) in the federated filtering configuration should be guaranteed because SINS is used as a common reference system. The paper investigates the FDI scheme suitable for the case in which at most two inertial instruments are infected with soft faults. The chi-square soft fault detection algorithm is presented, which is determined by parity vectors and suitable to soft faults detection. The maximum Likely-hood judgement rules to isolate soft faults are deduced in detailed, which is suitable to two instruments are infected with soft faults. The search scheme to get rid of the confusion in the fault isolation is induced. The fault detecting and isolating simulation of the inertial measurement unit with skewed redundant Ring Laser Gyros is done. The simulation results show that, even the soft faults are as tiny as the gyro drift, the faults still can be detected, and the faulty gyros still can be identified correctly.