On the use of robots and vision technologies for the inspection of vessels: A survey on recent advances

Vessels are widely used for transporting goods around the world. All cargo vessels are affected by two main defective situations, namely cracks and corrosion. To prevent major damage/accidents, intensive inspection schemes must be carried out periodically, identifying the affected plates for a subsequent repair/replacement. These inspections are performed at a great cost due to the arrangements that allow human inspectors to reach any point of the vessel structure while guaranteeing their physical integrity and respecting all the stipulated safety measures. Technological advances can provide alternatives to facilitate the vessel inspection and reduce the associated cost. This paper surveys approaches which can contribute to the reengineering process of vessel visual inspection focusing on two main aspects: robotic platforms which can be used for the visual inspection of vessels, and computer vision algorithms for the detection of cracks and/or corrosion in images. The different approaches found in the literature are reviewed and classified regarding their key features, what allows identifying the main trends which are being applied so far and those which could mean an improvement in the current visual inspection.