里程计辅助车载GNSS/INS组合导航性能分析

摘要

When GNSS outage occurs in a land vehicle GNSS/INS integrated navigation system,INS navigation error will be cumulated quickly.In order to improve positioning precision and integrity,odometer speed information and non-holonomic data are utilized to aid the integrated navigation system.We derive the output model of the odometer in consideration of the scale factor error of the odometer and the misalignment angle of IMU.The model,based on Kalman filter for the GNSS/INS integrated navigation aided by odometer,is deduced.A vehicle experiment is performed to verify the proposed method.The results show that the odometer can effectively restrain the error divergence of the navigation system.In case of GNSS outage of 60 s or 10 minutes,the positional accuracy is increased by more than 90％.%车载GNSS/INS组合导航中,GNSS信号易受外界干扰而失锁,导致INS独立导航误差迅速累积.为提高车载松组合导航系统的精度和完整性,使用里程计观测信息结合非完整性约束辅助车载组合导航.考虑里程计刻度系数误差和IMU安装角影响,推导出里程计的输出模型,给出基于卡尔曼滤波的里程计辅助GNSS/INS松组合的数学模型.设计GNSS信号中断的数据实验,结果表明,里程计能有效抑制组合导航系统误差发散,在GNSS中断60 s或10 min的情况下,位置精度提高超过90％.