多源组合导航系统故障检测技术研究

Research on Multi-source Integrated Navigation System Fault Detection Technology

为提高基于MEMS-SINS/GNSS/ODO/高度计的车载多源组合导航系统的可靠性,设计了带故障检测模块的联邦卡尔曼滤波器。针对残差χ^2检测法对缓变故障的检测灵敏度低,而改进序贯概率比(Sequential Probabitity Ratio Test,SPRT)检测法在故障结束后检测值需要长时间才能恢复到检测阈值以下以至于无法判断故障结束时间的问题,提出了一种残差χ^2-改进SPRT联合故障检测方法。该方法结合了两者的优点,根据系统故障综合决策规则进行故障判定,有效提高了故障检测的灵敏度和可信度。跑车实验结果表明,使用残差χ^2-改进SPRT联合故障检测方法进行故障诊断,能够快速检测出缓变故障和突变故障,通过及时的故障隔离,使导航系统更加适应当前的工作环境,增强了鲁棒性和可靠性,并保证了多源导航系统的导航精度。

In order to improve the reliability of the vehicle multi-source integrated navigation system based on MEMS-SINS/GNSS/ODO/altimeter,a federal Kalman filter with a fault detection module is designed.The residual χ^2 detection method has low sensitivity for slowly changing faults,and the improved sequential probability ratio(SPRT)detection method takes a long time to recover the detection value below the detection threshold after the fault ends,so that the end time of the fault cannot be determined.A residualχ^2-improved SPRT joint fault detection method is proposed.This method combines the advantages of both and makes fault determination according to the comprehensive decision rules of system faults,which effectively improves the sensitivity and credibility of fault detection.The sports car experiment results show that the use of residualχ^2-improved SPRT combined fault detection method for fault diagnosis can quickly detect slow and sudden faults.Through timely fault isolation,the navigation system is more suitable for the current working environment and enhanced robustness and reliability,and guarantee the navigation accuracy of multi-source navigation system.