The restoration of 3-D vision information about underwater targets is the key problem for an Autonomous Under water Vehical (AUV) to sense envirronmental information and perform autonomous tasks. This paper presents a model-based restoration method. This method makes the curve fitting based on the detected edge points of targets and restores the .3D information of targets using the model knowledge. The method has been employed

successfully

for the guidance of an AUV in its autonomous underwater operations.