Student-built Projectile Could Help Soldiers Detect Bombs, Chemicals

The crayon-sized sensor, which users fire from a standard paintball gun, was invented by a team of University of Florida undergraduate engineering students as part of a government- and corporate-supported engineering research and education program at UF. Lockheed Martin's Orlando-based Missiles and Fire Control, which sponsored the project, plans to refine the projectile and put it into production, and there is a chance it could be used in Iraq, Lockheed officials say.

"That (use in Iraq) was the original genesis," said Leslie Kramer, director and engineering fellow for Missiles and Fire Control, explaining the sensor would be an ideal tool for identifying improvised explosive devices, or IEDs – disguised homemade bombs that have injured and killed scores in Iraq.

"These IEDs – a lot of these things are being buried in piles of trash," he said. "If you had a good chemical sensor on this projectile, you could fire it into the trash and stand back and determine whether it could detect TNT leaking out of an artillery shell."

Guided by mechanical and aerospace engineering Professor Loc Vu-Quoc, a team of six engineering seniors designed and built the projectile over the course of the yearlong Integrated Product and Process Design, or IPPD, program. It was a challenge: Lockheed officials outlined what they wanted in broad terms and told the students to be creative. The team, which included students from several different engineering fields, considered numerous approaches, including a gun made of plastic tubing, before deciding to try an off-the-shelf paintball gun shooting a modified projectile.

The team built a tiny circuit board containing a transmitter, sensor and wire antenna, all powered by a watch battery. They inserted the circuit board in a cylindrical case tipped with the sticky industrial polymer. The weight of the polymer, together with the arrangement of the components, causes the projectile to be heaviest at the front, which helps it fly straight and strike the target with its sticky end.

"What we did was we made its tip heavy so it's like a dart – it doesn't tumble over," said electrical engineering student Felipe Sutantri.

Chemical and explosive detectors are expensive and difficult to work with, so the team tested their prototype using a tiny accelerometer, a sensor that registers movement. Accelerometers are commonly used in airbags to sense collisions. In a variety of tests, the team showed the accelerometers and other electronics could survive being shot out of the gun and striking a target. They were able to measure the accelerometer's data remotely at impact using oscilloscopes and laptop computers, much the way laptop-equipped soldiers might glean information from a deployed version of the projectile on the battlefield.

"I think the most important thing for the proof of concept was to see if the electronics could survive the impact," Sutantri said.

The students' tests proved the transmitter could report data from up to 240 feet from the laptop, while the paintball gun could shoot the projectile at least 65 feet. Both distances could be extended in the production version, and engineers also likely will shrink the projectile's size and weight.

"The next step is the integration of other detectors into this projectile and also modifying what the students did to make it more tactical," Kramer said.

Tara Plew, a research engineer at Missiles and Fire Control and the employee who worked most closely with the students, said the projectile "has created all kinds of excitement in the company," with two U.S. military bases asking for written descriptions of the device.

"The students went well beyond what we expected," she said.

Gregory Ivey said working on the sensor gave him a unique opportunity to put his skills to the test. "Instead of just learning something from a book, we actually got to apply it," he said.

Other IPPD program projects this year included a fully automated sandwich steamer for Jacksonville-based Firehouse Subs. The steamer allows workers to steam the meat and cheese ingredients for sandwiches far more rapidly than current versions. This may allow the chain to open more drive-throughs, said Chris Sorensen, who co-owns the company with his brother, Robin Sorensen. The chain now counts only two drive-throughs among its 139 restaurants.

"It's going to be phenomenal," he said. "There's a little tweaking here and there, but it will double the capacity of what we had before in terms of output in sandwiches."

Agricultural and biological engineering senior Jason Myhre, who worked on the steamer project, said it taught him a lot about how to team up with others with different backgrounds and expertise. The most beneficial part was overcoming "the challenge of working with each other's schedules and trying to get everyone to put forth their best efforts using their best talents" he said.