While landmines in general are pretty awful, the PFM-1 "butterfly" mine is particularly nasty. Because of its small size and mainly plastic construction, the butterfly-shaped device is notoriously difficult to find using metal detectors or other common methods. Now, however, it turns out that drones can be used to locate the things.
Led by professors Alex Nikulin and Timothy de Smet, a team from New York's Binghamton University mounted infrared cameras on inexpensive consumer drones, and then used the aircraft to conduct early-morning flights over an area in which PFM-1's had been surface-deployed (the mines are frequently dropped from the air, as opposed to being buried).
It was found that because the mines conducted heat from the rising sun much more quickly than the surrounding rocks did, they produced distinct thermal signatures that were easily picked up by the drones' cameras. This allowed the mines to be detected with a high degree of accuracy.
"We believe our method holds great potential for eventual wide-spread use in post-conflict countries, as it increases detection accuracy and allows for rapid wide-area assessment without the need for an operator to come into contact, or even proximity of the minefield," says Nikulin. "Critically, once further developed, this methodology can greatly reduce both costs and labor required for mine clearing operations across post-conflict regions."