Localization of AUVs for Ship Hull Inspection: A Review

Ship hull inspection is crucial for assessment of hull damage, biological fouling, and for detection of foreign objects (mines, illegal drug packages, etc.). These inspections require advanced planning, long periods of time, resources (people, facilities, equipment), and cost (time and money) to conduct. With this in mind, the purpose of this review is to provide an assessment of the state of the art technologies and techniques for ship hull inspection; identifying the key challenges and the directions for further research and development. This review first discusses platform types for inspection and imaging types, this discussion proposes that ship hull inspection could be completed quicker by using multiple imaging nodes, it also proposes that inspection complexity and resource could be reduced through use of autonomous vehicles. These proposals are the basis for the next sections of review where localization techniques and methods for node organization to achieve full coverage of the vessel being imaged become the focus. The review identifies that current techniques could be utilized, however require adaption and combination together for this specific use case. The conclusions from this review lead into what future research directions are required, focusing around the localization and organization issues.