Using a priori current knowledge on AUV navigation

This paper addresses the problem of incorporating, in the navigation system of AUVs, existing a priori information concerning the current fields in the site of underwater robotic missions. In our approach, deterministic information, in the form of expected current field in the mission area, are used to spatially control the gain of the Kalman filter that estimates the sea current. The robustness of this approach and its extension, taking into account the uncertainty affecting the a priori information, is also discussed. Several mission simulations using the predicted current field near the Rhone river estuary are presented, demonstrating the adequacy of the methodology proposed.