Error Overboundings of KF-Based IMU/GNSS Integrated System Against IMU Faults
Error Overboundings of KF-Based IMU/GNSS Integrated System Against IMU Faults
复制标题
基于 KF 的 IMU/GNSS 集成系统针对 IMU 故障的误差越界
DOI：
10.3390/s19224912
复制
发表时间：
2019-11-01
期刊：
影响因子：
3.9
通讯作者：
Fang, Kun
中科院分区：
文献类型：
--
作者：
Liu, Wei;Song, Dan;Fang, Kun
针对无人机惯性测量单元（IMU）故障风险，研究了IMU/GNSS紧耦合组合结构中扩展卡尔曼滤波（EKF）状态估计在IMU故障条件下的误差超界问题，以保证无人机导航系统的完整性。根据IMU故障传播的推导，得到了基于误差状态惯性导航方程的EKF（error-state inertial navigation equations based EKF）的误差上界，该误差上界可以表示为EKF新息、估计偏差和剩余位置误差的和。给出了与基于全状态惯性导航方程的EKF（full-state EKF）误差超界相同的表达式。仿真结果表明，误差状态EKF和全状态EKF的误差上界都能很好地拟合IMU故障时的状态误差，但误差状态EKF由于计算效率较高，更适合于无人机导航系统的完整性保证。这项研究将扩展到多传感器系统的完整性监测。
Considering the inertial measurement unit (IMU) faults risk of an unmanned aerial vehicle (UAV), this paper studies the error overboundings of the state estimation of the extended Kalman filter (EKF) in a tightly coupled IMU/global navigation satellite system (GNSS) integrated architecture under the IMU fault condition, which can be used to assure the integrity of the UAV navigation system. The error overboundings of the error-state inertial navigation equations based EKF (error-state EKF) are obtained according to the IMU faults propagation derivation, which can be expressed as a sum of the terms related to the EKF innovation, the estimated bias, and the remaining position error. It presents the same expression with the error overbounding of the full-state inertial navigation equations based EKF (full-state EKF). Simulation results show that both the error overboundings of the error-state and full-state EKFs can fit the state error against the IMU faults, but the error-state EKF is more suitable for UAV navigation system integrity assurance due to its higher calculation efficiency. This study will be extended to the integrity monitoring of multisensor systems.