AUV-Based Sonar Registration of Seafloor Features and Objects

In support of future U.S. Navy mine-hunting and surveillance systems, Imaging Microsensors Inc. (IMI) developed an innovative, lightweight, high-resolution, acoustic imaging method for identifying and locating natural seafloor features and objects that had been previously detected. The ability to re-acquire an object in sonar images, at arbitrary times and aspect angles, is critical to many applications involving underwater operations, including the reacquisition of a target, station keeping, maneuvering relative to stationary objects, mapping, and navigation by landmarks. Phase I showed the feasibility of the proposed method. Phase I modeled the acoustic response of seafloor features and objects, determined important system requirements, developed the basic registration algorithm, and identified sonar systems capable of supporting the algorithm. Also, Phase I developed a baseline design of an experimental system to be demonstrated in Phase II. Phase II will experimentally demonstrate an AUV-compatible system for acoustic registration of seafloor features and objects. Specifically, in Phase II, we will process existing real SAS data, complete the design of the experimental system based on lessons learned from processing such data, build the experimental sensor, refine processing algorithms, and perform an experimental demonstration of the acoustic registration system at Lake Travis Test Station of ARL, UT-Austin.