基于自适应卡尔曼滤波的NGMIMU/GPS组合导航设计

Design of NGMIMU/GPS integrated navigation system based on self-adaptive Kalman-filtering

由于加速度计输出动态噪声的存在,无陀螺微惯性测量单元(NGM IMU)导航误差随时间迅速累积.基于NGM IMU九加速度计配置方案,利用自适应卡尔曼滤波方法进行NGM IMU/GPS组合导航系统设计.滤波算法对滤波预测残差的大小进行判断,利用极大后验估计器推算出动态噪声和观测噪声的统计特性,克服了系统噪声统计特性不易确定的实际问题,使滤波器成为最优.同时进行了系统位移和角速度仿真,结果验证了自适应卡尔曼滤波方法的可行性.

In a Non gyro micro inertial measurement unit （ NGMIMU）, an inevitable accumulation error of navigation parameters is produced due to the existence of the dynamic noise of the accelerometer output. An integrated navigation system, which is based on a nine-accelerometer configuration of NGMIMU and a single antenna Global Positioning System （GPS）, is designed using a self-adaptive Kalman filter （SAKF）. For optimizing the filter, this approach solves the uncertainty of the statistical characteristics of the system noise by judging the prediction residuals of the filtering and calculating the statistical characteristics of the dynamic noise and the observed noise using the maximum a posterior estimator. A simulation case for estimating the position and the angular rate is investigated by this approach. The results verify the feasibility of the SAKF.