Odometer aided in-motion alignment based on strong tracking filter for land vehicles

In-motion alignment of strap-down inertial navigation system (SINS) for land use is researched in this paper. Alignment process is accomplished in 10 minutes by using the information from a combined odometer whose installation angles from vehicle body frame (VBF) to INS body frame is not calibrated. The difference of the SINS velocity result and the odometer measured velocity projected to navigation coordinate is taken as the measurement for the filter. Focusing on the problem that the statistic property of measurement noise is vague causing by the installation angles and the inconstant scale factor error of odometer, a strong tracking kalman filter (STKF) is employed and designed in the in-motion alignment of the SINS/OD integration navigation system. The experiment result shows that compared with traditional kalman filter (KF), STKF has faster convergence speed and higher accuracy, particularly in azimuth error improved greatly.