基于CKF和R-T-S平滑的车载SINS/OD动基座对准方案

Moving Base Alignment Scheme for On-board SINS/OD Combination Based on CKF and R-T-S Smoothing

为提高车载捷联惯导/里程计组合系统的动基座对准精度、速度和位置导航精度,提出了"容积卡尔曼滤波(CKF)非线性对准+非线性R-T-S平滑+再次Kalman滤波线性对准"的方案,即首先应用CKF进行非线性对准,对准结果方位对准精度一般、位置误差较大;接着利用R-T-S平滑获得初始时刻高精度对准结果,此时非线性误差模型退化为线性模型;最后再进行Kalman滤波线性对准而获得高精度方位对准精度和位置导航。该方案无需长时间的粗对准,最终能获得高精度的结果。实车试验验证了该方案的有效性。

In order to improve the alignment accuracy and speed and the accuracy of position navigation of moving base in a strapdown inertial navigation system/odometer （SINS/OD） combination,a scheme of ＂ nonlinear alignment by cubature Kalman filter （CKF） ＋ nonlinear Rauch- Tung-Striebel （R- T- S ） smoothing ＋ linear realignment by Kalman filter＂ is proposed. Specifically,a nonlinear alignment is conducted by CKF first with a result of ordinary azimuth alignment accuracy and a relatively significant position error,then a nonlinear R- T-S smoothing is performed to obtain a high accuracy alignment result at initial moment with the nonlinear error model degenerated to linear model,and finally a linear realignment is carried out by Kalmann filter to obtain high accuracy azimuth align-ment and position navigation. The scheme can obtain a high accuracy result without time-consuming coarse alignment,and the real vehicle test verifies the effectiveness of the scheme proposed.