Redundant INS/ADS System's Fault Detection and Isolation Based on Dempster-Shafer Evidence Reasoning

In allusion to residual chi-square test method has low sensitivity for soft fault detection and cannot isolate the faulty system in integrated navigation system, a redundant INS/ADS fault detection and isolation method based on Dempster-Shafer (D-S) evidence reasoning is proposed in this paper. In this method, three INS/ADS and three INS/GPS sub-filters are constructed respectively by introducing intact GPS in the three redundancy INS/ADS system, and the difference between the residuals of each two sub-filters is used as evidence, then the fault detection of sub-filters is completed by using D-S evidence reasoning. On this basis, the fault isolation and system reconstruction methods are given, and the fault isolation of the INS/ADS integrated navigation system is realized. The simulation results show that the proposed method can not only improve the sensitivity of soft fault detection, but also isolate the fault system in integrated navigation system.