New Drone to Search for Landmines by Reading the Leaves

A U.K. university hoping to sell Cambodia what would be the first aerial drones of their kind in use anywhere around the world says the kit could help clear the country’s minefields by taking high-resolution images of contaminated areas and picking up evidence of leaked chemicals from buried ordnance.

Researchers from the University of Central Lancashire were in Pursat province last month for field tests with the military’s National Center for Peacekeeping, Mines and Explosive Remnants of War Clearance (NPMEC), which is considering the purchase.

“The capabilities of the drones to produce high-quality maps of the minefields is second-to-none and a valuable addition to help demining efforts,” Darren Ansell, lead space and aerospace engineer at the university’s school of computing, engineering and physical sciences, said in an email.

“Simply by flying over a site, we can produce a large geo-referenced map, a 3D model and a digital terrain map which is far better than the hand-drawn maps that currently exist,” he said. “Ultimately, we would like to combine the sensor measurements from multiple airborne and ground drones to improve the probability of detecting buried mines.”

In addition to mapping the terrain, the drones would use infrared cameras to find evidence of buried mines and unexploded ordnance by looking at the surface vegetation, which absorbs and reflects light in different ways depending on how healthy it is.

“Buried landmines can leak chemicals which affect the health of the plants that grow above them, so by using this technique unhealthy plants can be an indication of a buried object,” Mr. Ansell said.

While others have been studying the use of drones to find landmines, and infrared images are already being used to gauge plant and crop health, he said, “To the best of our knowledge, our combination of equipment has not been used elsewhere.”

The researchers hope the drones will help make the slow and expensive work of mine clearance faster and cheaper, but it’s no panacea.

Many of the millions of mines and cluster bomblets still scattered across the country are no bigger than a tennis ball. Others, like anti-tank mines, are buried more than one meter deep.

Mr. Ansell said those cases could be a challenge for the drones. “Not all techniques work with all types of ordnance, so a combination of techniques is needed, including ground penetrating radar to maximise chances of detecting ordnance that is not leaking underground.”

Heng Ratana, director-general of the government’s Cambodian Mine Action Center (CMAC), said the drones would best be used for mapping terrain.

“It will give better information for mapping,” he said, and with better mapping, “you will deploy your resources in better areas and more precisely. You can have better planning.”

But CMAC, by far the largest demining operator in Cambodia, is not interested in buying any of the drones for itself. Mr. Ratana said he was happy buying precision maps of target areas from Google, saying there was “not very much difference.”

The Mines Advisory Group (MAG), an international demining operator that works in Cambodia, has been using drones to map local terrain more than a year, but without the multispectral cameras.

MAG regional director Greg Crowther said combining the two has been talked about for years, though he was skeptical that it would be much of a game-changer in Cambodia.

“My feeling would be that the tools we have available…offer us the resources we need to get the mine clearing done in the next eight to 10 years with the appropriate funding,” he said.

Cambodia is aiming to have its minefields cleared by 2025.

The designers of the new gear hope their combination of drones and cameras will help Cambodia clear more land for less money. Mr. Crowther said that will depend on how much it will have cost to bring all the technology to market—and, eventually, to buy—and whether the money would have been better spent on what deminers are doing already.

The NPMEC said the various drones being tested could cost from $20,000 to $160,000, but Mr. Ansell said that was far off. He said the university tested a commercial drone that cost approximately $20,000, but added that they could build one fit for purpose for “much less.”

The NPMEC hopes to have the results of last month’s field tests some time next week.

[email protected]

Related Stories

Latest News