First sea trial of underwater observation system using autonomous towed vehicle

This paper discusses an autonomous towed vehicle for underwater inspection in a port area, in which a sea current is so fast and complex. The autonomous towed vehicle has three different navigation modes; towed mode, autonomous mode and kite mode, to assure safe and reliable inspection in such a port area. In this paper, we describe the results of a tank experiment and a real sea trial using this prototype model to verify the effectiveness about our proposed system. The towing test was executed and the suitable values of the control parameter in the proposed system were decided. Next, the stability of the vehicle in the towed mode was con finned and a depth constant, a heave and pitch control was performed successfully in the real sea area experiments. And it was confirmed that the way point control was possible in an untethered mode.