Following a terrorist's recipe for blowing up a plane is a good way for human bomb-makers who study these recipes to risk death themselves. But a fearless new robot named "LEXI" can help the U.S. Department of Homeland Security cook up potentially unstable explosive mixtures for the sake of studying terrorist tactics.
LEXI works inside the "firing tanks" used for testing the power of homemade explosives at the High Explosives Applications Facility of Lawrence Livermore National Laboratory in California. The robot's job is to take explosive cocktails from a vibrating mixer and place them on a firing table to prepare for detonation — a task too dangerous for humans to handle.
"We need to see what a terrorist might use and how effective certain types of explosives might be in bringing down planes and other targets of interest," said Lee Glascoe, an engineer at the Lawrence Livermore National Laboratory.
The robot hides behind a blast shield as an acoustic mixer vibrates to mix bomb ingredients into an explosive mixture. LEXI only comes out into the open to move the bomb mixture to the firing table before rolling out the firing tank's door to escape the blast zone prior to detonation.
Such robotic precautions have enabled the National Explosives Engineering Sciences Security (NEXESS) Center — a program is funded by the Department of Homeland Security — to test the explosive power of possible bomb mixtures used by terrorists.
"There are a lot of materials that we look at, and many are safe to work with in contact, such as with your hands, if you know what you are doing," Glascoe explained. "But there are many that are not; particularly if they have certain additives like sulfur or aluminum."
LEXI represents a modified iRobot Packbot 510 — a battle-tested robot made by the company that also produces Roomba vacuum cleaners. But LEXI's unique job of assisting bomb-making stands out compared with its fellow iRobots that usually help U.S. soldiers disable roadside bombs in Iraq and Afghanistan.
"Before LEXI, we weren't able to look at some of these explosives because of safety concerns," Glascoe said.