Researchers Give Machine a Nose to Find Land Mines

Researchers at Tufts University Medical School are teaching a machine to do what humans cannot--sniff out land mines.

In controlled testing conditions, the machine can detect odors at two parts per billion, which equals the performance of trained dogs. The inventors hope it will successfully detect land mines in open-field conditions in two years.

“It’s an extremely difficult task” to smell explosives used in most land mines, said John Kauer, who is working on the project with fellow neuroscience professor Joel White. “These are odors you or I cannot smell.”

The machine Kauer and White have built differs from existing artificial noses in two ways. It is specifically designed to search out land mines, and it is built to simulate the way animals detect odors.

The machine has an air intake, which brings odors into a box that contains 32 sensors. The machine is programmed to recognize the signature patterns of certain odors. It also has a simulated voice to tell operators what it has found.

Artificial noses are not new. The technology was first developed in 1982, but they are often used to tell the difference between kinds of coffees or cheeses.

But White and Kauer, who are researching the way animals detect smells, decided to take their research a step further and see if a machine could replicate the sense.

The machine has been tested at an inactive minefield at Ft. Leonard Wood in Missouri with limited success. “The movement of air disturbs the plume or odor,” Kauer said.

The project is funded by the Defense Advanced Research Projects Agency, the central research and development agency of the Defense Department.

The agency is also funding studies of honeybees, which can detect vapors given off by land mine explosives. Researchers have successfully placed sensors in bee hives that can tell if a bee has detected an explosive and brought back traces to the hive.

In February, Regina Dugan of DARPA said systems that detect vapors from land mines are “the holy grail of mine detection.”

The United States, China and Russia have yet to sign the 1997 treaty outlawing land mines. It has been signed by 138 nations and ratified by 101.

According to Physicians Against Land Mines, there are more than 60 million unexploded land mines in 70 countries, killing or maiming a civilian every 22 minutes. The present technology for finding them includes infrared and ground radar systems, heavy rakes and rollers, and searching by hand.