US landmine detector made from off-the-shelf components

In a project sponsored by the US Army Research Laboratory’s Army Research Office, Prof John Scales, his collaborator Martin Smith and students at the Colorado School of Mines have built a new system using microwave-based sensors to detect vibrations in the ground (or other structures) remotely.

Made from off-the-shelf components the system costs about $10,000. This compares to laser-based Doppler remote detection systems that sells for upwards of $1m. Microwaves have many other advantages including that they can see through foliage.

‘Land mines are an enormous problem around the world for both military personnel and civilians,’ said Scales. ‘We’ve developed an ultrasound technique to first shake the ground and then a microwave component to detect ground motion that indicates location of the land mine. We hope that the two components together enable us to detect the land mines in a safe fashion, from a distance.’

Many other applications are said to exist for remote vibration sensing, including monitoring the structural integrity of buildings, bridges, and dams.

Multiple approaches exist for land mine detection, from trained dogs and rats that detect chemicals used in explosives to biosensor plants that change colors in response to soil conditions altered by mines.

“The reason so many people are working on this problem from so many angles is there is no one scheme that works well all the time,’ said Scales. ‘You need an arsenal of tools.’

The work is described in the Journal of Applied Physics.