Fish Caught in a Net
An AUV inspecting a pipeline could be snared in an abandoned fish net. DIDSON can image the fish net and serve as an obstacle avoidance sonar as well as an inspection tool. The strands of the net can be seen out to at least 7 m. The strands are a bundle of 8 monofilaments each 0.2 mm in diameter, bundle diameter is 0.6 mm, mesh size is 73 mm square. During this exercise, a 50-cm salmon was accidentally caught, then released.