In-Motion Initial Alignment for Odometer-Aided Strapdown Inertial Navigation System Based on Attitude Estimation

This paper investigates the in-motion initial alignment for odometer-aided strapdown inertial navigation system with main focus on handling the severe disturbance inherent in the odometer. An attitude estimation-based alignment method is proposed through ingeniously attitude matrix decomposition and velocity rate equation reconstruction. The attitude estimation-based method can attenuate the disturbance in the odometer to a certain extent and can avoid some additional approximations. However, the severe disturbance in the odometer cannot be handled adequately by the attitude estimation structure. In this respect, a low- pass finite impulse response digital filter is used to attenuate the disturbance in the odometer preliminarily. Experimental results are reported to validate the effectiveness of the proposed alignment methods and the superiority of attitude estimation-based method over attitude determination-based method.