基于低通滤波的GPS/INS组合导航模型研究

Study on Low-pass Filter Based GPS/INS Integrated Navigation Model

惯导系统中惯性元件误差是影响惯性导航及组合导航精度的重要因素。本文首先分析了INS加速度计及陀螺仪在不同方向上的原始观测数据误差源及其相关作用,并给出低通滤波及GPS/INS(Global Positioning System/Inertial Navi-gation System)组合导航模型。在此基础上,提出采用低通滤波器消除INS原始数据中的高频随机误差,提高GPS/INS组合导航精度的技术路线。模拟INS的线速度及角加速度原始观测数据,对本文模型进行INS自主导航测试,导航精度得到明显提高。进一步采用实测数据进行组合导航分析,滤波前后计算的位置误差比较可以看出滤波后的导航解要优于滤波前,X、Y、Z三个方向上导航精度分别提高了15.1%、28.3%、28.1%。在残差最大值的比较上,三个方向上都有所减小,说明本文模型可有效提高导航精度。

After analyzing the raw observation data error sources of accelerometer and gyroscope in different directions and introducing the principle of low pass filter and the model of GPS/INS integrated navigation,a technical route aiming at improving the precision of integrated navigation which apply the low pass filter to eliminating the random high frequency noise of IMU raw observation data.The test of autonomous navigation shows that above model is able to improve the navigation precision to some degree.The future analysis is discussed to compare the position error calculated before filtering with after filtering by using the measured data.The results show the navigation resolution is better after filtering.The navigation precision increases by 15.1%,28.3%,28.1% and the maximum of residual decrease to some degree in X,Y,Z direction.All of test indicates that the model proposed in the paper can improve the navigation precision effectively.