Reducing the computation time in the state chi-square test for IMU fault detection

This paper introduces a hierarchical structure of filters and proposes the state chi-square test (SCST) with newly modified propagator for detecting an accelerometer and gyro fault. All filters in the hierarchical structure of filters include the inertial navigation system (INS) as a common reference system. That is why it is essential to detect the INS fault in the hierarchical structure of filters. The newly modified propagator based on two propagators and N-step propagator is proposed to make up for each weakness. The modified propagator can reduce a fault alarm ratio (FAR) and a computation time. In this paper, it is shown that the SCST with the modified propagator has better performance than the SCST with conventional one in the computer simulations.