An Army research physicist has invented a “high-frequency electromagnetic induction instrument,” which detects low and non-metallic improvised explosive devices.
Dr. Benjamin Barrowes, from the U.S. Army’s Engineer Research and Development Center’s Cold Regions Research and Engineering Laboratory, invented the novel detector for finding non-metallic, unexploded shells made of carbon fiber that had been fired on U.S. military ranges. The invention was patented in 2018. (Download the patent PDF below.)
“Carbon fiber is more conducting than the ground but less conducting than metal. Thinking about what actually happens when we bring these frequencies close to metal, I realized that the electrons in less conducting targets needed to be pushed harder in order to respond like they do in metals because it is difficult for electrons to move in less conducting targets, kind of like moving your hand through water as opposed to moving your hand through the air.
“The way to push electrons harder at these frequencies is to use a higher frequency, so that is the direction we went in while maintaining the set of physical assumptions that we used in our models and our understanding,” Barrowes said in a recent Army report.