Harbor Shield: A new technique for inspection of vessels below the waterline

In 2007, the Naval Undersea Warfare Center, Newport RI, Battelle, and EdgeTech Marine demonstrated acoustic imaging of ships´ underhulls from a fixed sensor while the ship was underway. This served as proof of concept for a maritime security development called ldquoHarbor Shield.rdquo At present, inspection by divers is the only way to detect and classify objects attached to ships´ hulls. Harbor Shield, which inspects moving ships from a stationary portal instead of using mobile ROVs or divers to inspect stationary targets, may dramatically increase shipping inspection rates while reducing the commercial impact of inspections. The 2007 data was used to develop techniques to optimize image extraction from the single sensor then used. A developmental single transmitter/ multiple-receiver sonar system should allow three-dimensional imaging of the underhulls of ships while underway. Current efforts focus on development of a prototype portal to generate data needed to optimize design and operation.