Multi-sensor data fusion for seafloor mapping and ordnance location

Results of ongoing work in developing methods for performing multi-sensor fusion for the purpose of locating unexploded ordnance in shallow water and creating models of the sea-floor for visualization are presented. The sensor suite includes a forward-looking sonar, a low LF side-looking sonar, a HF side-looking sonar, a magnetic field gradiometer, and an electro-optic laser-scanning sensor. Data fusion techniques discussed include an iterative method of performing automatic target recognition processing (ATRP) on individual sensor channels, correlating the individual sensor channels for a single pass using the target locations to assist the process, performing correlations on multiple passes over the same target area, and returning the correlated data to the ATRP algorithms. The second pass of the ATRP algorithms on the correlated data provides an additional method for locating and identifying targets while rejecting clutter. Correlated sensor data, along with GPS information, is used to create 3D models of the sea floor. The sea-floor models are used for visualization of the area around an item of unexploded ordnance.