Research on AUV Cooperative Positioning Technology Based on Improved-EKF With Error Estimation

Aiming at the data fusion problem in the Leader-fellow cooperative positioning system of multiple autonomous underwater vehicles (AUV), the mathematical model of the Leader-fellow cooperative positioning system is established, and then the speed error and heading error are analyzed to position the fellow AUV At the same time, an improved- EKF filtering algorithm with the ability to estimate the measurement error of navigation equipment is designed. The distance information between the leader and fellow AUVs obtained by acoustic ranging is used as the measurement information to estimate the position, speed error and heading error of the fellow AUV. In order to verify the effectiveness of the algorithm, the cooperative positioning algorithm with error estimation capability is verified by simulation experiments and offline data from ship navigation experiments on the lake. The results show that the proposed improved-EKF algorithm can effectively reduce the positioning error of the fellow AUV. It is especially obvious when the AUV is autonomously positioned, which greatly improves the navigation and positioning capabilities of the fellow AUV.