A low-cost, autonomous surface vehicle-based system for unexploded ordnance bistatic acoustic localization and classification

A growing application for unmanned vehicle technology is the localization, classification and mitigation of underwater hazards such as munitions in shallow harbor environments. Because visual inspection of targets can be difficult or impossible in murky harbors and requires precise target localization, acoustic sensors such as sidescan sonar and synthetic aperture sonar (SAS) are used more extensively for munition detection missions. While these techniques can provide rich images of targets and the environment, postprocessing is often required and the sensors themselves are too expensive to be practical in multi-vehicle operations. A new system for low-cost, autonomous-surface-vehicle-based unexploded ordnance detection and localization is under development to provide a practical alternative to provide greater coverage via distributed, multi-vehicle missions. A mobile receiver array, fixed source geometry makes it possible to cover large areas while detecting man-made, aspect-dependent targets based on directional scattering from seabed targets. The system built on a Woods Hole Oceanographic Institution JetYak autonomous surface vehicle and results from experiments in summer 2019 in Ashumet Pond in Falmouth, Massachusetts are presented. [Sponsored by SERDP.]