“Updating the Marine Towed Array for Advanced Geophysical Classification" by Dr. Dan Steinhurst
Although unexploded ordnance (UXO) exists at many underwater sites and presents a significant human health risk, the combination of unfriendly survey conditions and technology gaps currently prevent routine, systematic detection and classification of UXO in the underwater environment. The Marine Towed Array (MTA) is an underwater dual-mode sensor array that was successfully demonstrated at multiple marine venues in support of SERDP and ESTCP projects beginning in 2004. It provides both marine electromagnetic and marine magnetic sensors to detect and map underwater UXO. The electromagnetic imaging (EMI) sensor array is based on older technology. Several ESTCP demonstrations have shown that older technology is not able to support advanced geophysical classification (AGC). Under ESTCP project MR-201610, the Marine Towed Array was upgraded with with modern, advanced EMI electronics and the sensor array was replaced with a modern, multistatic array design. The ability to classify the detected anomalies from survey data can dramatically improve the state of the art for underwater UXO remediation by reducing costs and improving efficiency. This presentation focused on the results of these efforts to return the MTA to service and validate the new EMI array’s design for UXO detection and classification in the underwater environment.
“Near-Shore Deployment of Geophysical Sensor Arrays from Remotely and Autonomously Operated Platforms" by Dr. Gregory Schultz
Important near-shore applications, including UXO surveys, salvage and underwater infrastructure characterization, require man-made targets on or below the seafloor to be detected and geo-registered. Investigations in these littoral environments are time-consuming and expensive due to the challenges of tracking underwater assets, quick and effective site reconnaissance activities, high levels of clutter in nearshore areas, and lack of situational awareness and real-time feedback to operators. Consequently, there is a high payoff for new integrated platforms that combine mobility, navigation and high-resolution geophysical surveying. Recent research efforts have demonstrated deployment and sensing technologies at multiple continental United States near-shore sites, with a focus on improving surveying and mapping of underwater munitions. These efforts strives to overcome challenges in integrating magnetic and controlled-source electromagnetic (EM) sensor arrays on a variety of remotely and autonomously operated sensing platforms (remotely operated vehicles [ROVs], autonomous underwater vehicles [AUVs] and bottom crawling systems). Results from tests conducted on shallow reefs in the lower Florida Keys and surf and sound near the Outer Banks of North Carolina show the value of integrated systems for a variety of applications. Pilot studies were conducted of both bottom crawling and hydraulically propelled/swimming AUVs with integrated EM sensing systems to search and map UXO.
Dr. Dan Steinhurst is a Senior Staff Scientist working for Nova Research in Alexandria, Virginia. His current research focuses on the development of advanced EMI sensors for use in underwater environments and characterizing the impact of conducting media and sediment variation on UXO/clutter classification. He has served as co-Principal Investigator and Principal Investigator on several SERDP and ESTCP projects over the last decade to develop, demonstrate and advance EMI sensor platforms for Advanced Geophysical Classification. Dr. Steinhurst helped lead a team effort that resulted in the development of the Naval Research Laboratory (NRL) time-domain electromagnetic modernized target acquisition designation sight (TEMTADS) 2x2 man-portable system. He received a Ph.D. in Physical Chemistry from the University of Arizona in 1999, followed by a National Research Council post-doctoral fellowship in the Chemistry Division at the U.S. Naval Research Laboratory ending in 2002.
Dr. Gregory Schultz is currently a Senior Research Scientist and the Chief Technology Officer at White River Technologies. He has been conducting research and development on near-surface geophysical site characterization, and leading efforts to develop and transition magnetic and electromagnetic sensor systems for military and environmental applications. His current research interests include coastal and marine geophysics, electromagnetic phenomenology, autonomous and robotic sensing systems, and hydrogeology. Dr. Schultz received his Ph.D. in Geophysics from the Georgia Institute of Technology.