EKF SLAM using acoustic sources for autonomous underwater vehicle equipped with two hydrophones

Development of localization method is crucial for underwater vehicles to navigate in underwater environments. This paper presents a method of localization for underwater vehicles using acoustic signal. Artificial underwater acoustic sources are used as landmarks in underwater environment and underwater vehicle performs localization by acquiring acoustic signals transmitted from the sources. TDOA based method is used to acquire directional angle of acoustic sources with bayesian process. Then, EKF-SLAM is performed to estimate vehicle pose and locations of acoustic sources by fusing inertial sensors and directional angles of acoustic sources. Experimental results of a sea-trial verify the performance of the proposed method. The proposed method can provide a reliable estimation of the direction and location of the acoustic source, even under for a noisy acoustic signal. Experimental results verify the performance of the proposed method in a real sea environment.