Development of passive acoustic landmark using imaging sonar for AUV´s localization

We proposed and tested a passive acoustic landmark that can provide accurate navigation information for an autonomous underwater vehicle (AUV). The AUV used imaging sonar mounted on the vehicle to recognize shadows of the columntype landmark, and can measure vehicle´s own pose and relative position from the landmark which was set in a known position. The results of the proposed method had acceptable error (<;1 %) in the calculated position of the AUV. The proposed localization method will be useful to correct drift errors of inertial navigation systems for the AUV or to find the same position repeatedly.