Jurmain, currently a graduate student at the Thayer School, is working on a new invention to help military convoys in Iraq and elsewhere avoid roadside bombs known as EFPs, or explosively formed penetrators. Jurmain created the technology to counter the most common EFP design, which resembles a coffee can-sized cylinder containing explosives with concave copper disks that are approximately a quarter-inch thick attached to their ends.
"When it detonates, the force of the explosion liquefies the copper disk to a bolt of glowing metal that shoots out at hypersonic velocity," Jurmain said. "The force of it and its heat will drill right through armor, and spreads throughout the passenger cabin and can kill people."
EFPs, which detonate in response to motion, contain sensors similar to those used in home security lighting. Jurmain found vulnerabilities in the passive infrared sensors that detonate the explosives, he said. While normally EFPs explode under a vehicle, Jurmain discovered that a device mounted to stick out ahead of a vehicle can trigger the explosives earlier, he said.
"The idea is that you have a telescoping pole with an infrared emitter on the end," he said. "When [military personnel are] driving on the highway, they can extend the pole to one additional vehicle length that effectively doubles the length of the vehicle. The emitter on the end sets off any roadside bombs set off by a particular motion sensor."
Jurmain said he discovered a possible emitter that was inexpensive and commercially available for this technology: reptile heat lamps from pet stores.
"It's cheap enough that you can build it with parts from PetCo and Home Depot," he said.
The new technology could reduce casualties from roadside bombs by up to 50 percent, Jurmain said, and would help prevent EFP denotations from severely damaging military convoys. Although the technique is only a partial solution, it will decrease insurgents' ability to execute surprise explosive attacks successfully, Jurmain said.
"It forces them to guess where [the vehicle] will be, and they will only get it 50 percent of the time," Jurmain said. "Then there will only be a fraction of that percentage where the bombs will then actually hit a critical zone of the Humvee like the engine or the passenger cabin."
Jurmain's current prototype is the second project he has worked on for military use. Three years ago he helped a team engineer "Hazbot," a robot prototype that allows emergency responders to dispose of hazardous material easily and quickly, Jurmain said. He began developing the prototype while working as an intern at iRobot Corporation, and later collaborated with Dartmouth Medical School professor Joseph Rosen, an adjunct professor at the Thayer School and a plastic surgeon at Dartmouth-Hitchcock Medical Center.
"Jake arrived at the right time with the right interests and skills to fill the internship," Rosen said.
Jurmain, Rosen and their team received a $60,000 grant for the project from the College's Institute for Security Technology Studies, which is funded by the Department of Justice, Jurmain said.
The Department of Defense and defense companies expressed interest in the robot after the prototype was completed, Jurmain said.
Jurmain's counter-EFP technology has not yet received the same level of interest from defense companies, mainly because the project proposal has not yet been finalized, Jurmain said.
The device is currently being marketed to several groups, including Force Protection Inc., a company that has invented other technologies currently used to protect military vehicles.
