Improving visual odometry for AUV navigation in marine environments

Visual odometry is usually integrated in the localization and control modules of underwater robots, combined with other data coming from diverse instruments and sensors, such as, Doppler Velocity Logs (DVL), pressure sensors or inertial units, to compute the vehicle motion and pose by means of death reckoning. Dead reckoning is subject to cumulative drift, and, in underwater scenarios is specially afected by the challenging structures, color textures and environmental conditions (currents, haze, water density, salinity, wind, etc...), increasing the need of specifc improvement or adjustment to this media. This article presents preliminary results of an evolution of the well known VISO2 stereo odometer, modifed in order to improve its performance when run online in marine scenarios, and from a moving Autonomous Underwater Vehicle (AUV) equipped with cameras pointing downwards to the sea bottom.Peer Reviewe