Experiments in laser-assisted visual sensing for AUV navigation

Abstract The Cranfield University torpedo-shaped underwater vehicle has been modified to accommodate a laser stripe illumination system. As well as providing enhanced viewing capabilities, this system derives real-time navigational data during the mission and gathers images to produce a post mission enhanced optical waterfall image of a surveyed area. This paper describes a preliminary set of constrained motion trials at the IFREMER wave basin in Brest, where the system was towed through the 50 m test tank at different altitudes and orientations whilst the true trajectory was measured. A comparison is made between ground truth trajectory generated from these external measurements and that derived from the video camera and rotation sensors internal to the vehicle.