Ship hull inspection: A survey

To ensure the safety of ship navigation, a regular hull inspection is essential, which can identify affected structures and guide the appropriate maintenance. Traditional hull inspections severely rely on inspectors who tour the entire hull and perform close inspections, which are tedious, subjective, dangerous and expensive. The applications of computer algorithms and robots to data processing and data collection respectively have been receiving increasing attention, to facilitate hull inspections and reduce costs. In this paper, we first review the background knowledge of hull inspection. Then we categorize different inspection approaches into three classes: in-dock, underwater and health monitoring based inspections and conduct an extensive, deep survey. In addition to manual inspection approaches, we survey both the automatic data processing methods and automated platforms used to improve the efficiency and effectiveness of hull inspection. Different approaches are reviewed based on the type of Non-destructive Testing (NDT) techniques, data processing methods and automated platforms. Discussions are further made regarding the existing work. To our knowledge, this study is the first survey performed in such an extensive manner, which can help both the research and industry colleagues build up an overall understanding of hull inspection and identify potential directions for future development.