Several countries suffer from the existence of millions of buried landmines in their territories. These landmines have indefinite life, and may still cause horrific personal injuries and economic dislocation for decades after a war has finished.
Landmines, improvised explosive devices (IEDs), and other homemade bombs struck 6,461 people worldwide in 2015, killing at least 1,672, according to a report by the International Campaign to Ban Land Mines and Cluster Munition Coalition. Survivors are often left with devastating injuries. In a study published in BMJ Open, 70 percent of people hit by IEDS in Afghanistan required multiple amputations. According to the UN Mine Action Service, landmines kill 15,000–20,000 people every year (mostly children) and maim countless more across 78 countries.
IEDs were responsible for approximately two-thirds of U.S. and Coalition casualties suffered in Iraq and Afghanistan. Civilian casualties from IEDs number in the tens of thousands. A Navy explosive ordnance disposal expert with multiple tours in Iraq and Afghanistan characterized the influence of IEDs on the conduct of operations in those countries this way: “No other weapon shaped the battlefields in Iraq and Afghanistan like the IED. It required that troops charged with enhancing population security confine themselves to massive, armored vehicles and travel at high rates of speed or plow through farmers’ fields to avoid roads entirely. It slowed dismounted troops forced to sweep with metal detectors and divert around empty intersections. It partitioned Baghdad with 12-foot high concrete walls and caused a fertilizer shortage for farmers in Afghanistan. It was the only insurgent weapon that could cause mass civilian casualties, undermining local governance, the credibility of counter-insurgent efforts, and ensuring a steady stream of atrocities — of the horrors of intervention — could be broadcast globally.”
Many technologies have been employed in detection of landmines from metal detectors to ground penetrating radar, acoustic and Electric Impedance Tomography (EIT) to Infrared Imaging Systems. Each technique is suitable for detection under some conditions depending on the type of the landmine case, the explosive material, and the soil.
Robotic vehicles and drones are also being increasingly employed for mind detection and clearing, to reduce the risk to the personnel. Several groups have built and tested aerial platforms that can scan potential minefields, either using hyperspectral imaging, metal detection or even laser beams, with a view to pinpointing mine locations, and even remotely detonating them.
Harshwardhan Zala, a 15-year-old boy from the city of Ahmedabad in India, has a passion for saving lives across the globe. Zala has built drones that detect landmines and already has a handful of patents at his young age. The South Korean army has shown interest in his company, Areobotics7 Tech Solutions, and the technology he has invented. Zala claims that his drones landmine detection accuracy is 93% opposed to currently used technology that has an accuracy of 51%.
Improvements in UAV technology have made possible the development of UAV-assisted landmine detection systems, as they exhibit disruptive advantages such as:
i) higher scanning speed compared to existing solutions in the market based on autonomous robots;
ii) possibility of inspection of remote areas, unaccessible with other systems; and
iii) higher safety throughout the scanning process, especially when looking for explosives, since contact with soil is avoided.
Researchers have built a prototype consisting of a metal detector onboard a UAV that also includes a robotic arm capable of placing a remotely controlled detonator to blow out the landmine. This system provides contactless (and thus safe) and fast scanning capabilities. However, metal detectors cannot distinguish between different kinds of metallic targets. Furthermore, non-metallic buried explosives cannot be detected.
Latest advances for landmine detection are based on placing a GPR on board a UAV. The implemented prototypes are mostly based on a compact GPR unit that forwards geo-referred measurements to a ground station for post-processing and results displaying. Again, cross-range (horizontal) resolution is limited by positioning and geo-referring accuracy, mostly relying on GNSS receivers integrated within the UAV controller. In consequence, these state-of-the-art systems have been proved to be effective for detecting buried targets larger than 25-30 cm, and/or exhibiting significant contrast with the medium (e.g. metallic targets buried in clay or sand).
However, existing UAV-based GPR systems do not provide high resolution subsurface images as they do not support SAR imaging capabilities, that is, GPR measurements collected at each position of the flying path cannot be coherently combined. This is because positioning and geo-referring accuracy using GNSS-based techniques is in the order of 50-60 cm n the best case. Thus, enabling SAR imaging techniques (i.e. coherent combination of measurements) requires the use of cm- or mm- level accuracy geo-referring and positioning
US Navy tests aerial drones for real-time mine detection
In 2017, US Navy tested an aerial drone platform that can locate and identify land mines in real time. The idea is to use such a system for real-time threat identification during combat operations.
The Mine Warfare Rapid Assessment Capability system (MIWRAC) comprises a portable one-pound (0.45-kg) quadcopter, equipped with a proprietary magnetometer suite and processing algorithms to detect buried and submerged mines. This information is sent back to an Android tablet, where a green map of the area is marked with red clusters highlighting potential danger. The idea is to give sailors and marines an information edge as they go in for amphibious beach landings. This technology will help Sailors and Marines who are approaching a beachfront to rapidly clear, or at least determine the location of, mines or other hazards that are in their way,” says ONR Command Master Chief Matt Matteson. “It could potentially save a lot of lives.”
DTU to Work on New Mine Detection Drone
Researchers at Technical University of Denmark – DTU have received DKK 11 million from Innovation Fund Denmark to develop a drone with magnetometers capable of mapping mines in former war zones. The new demining system consist of developing a ‘magnetometer bird’, a frame with embedded magnetometer, which is attached to the drone and hangs approx. 5-10 metres below it.
“The plan is for our drone and its unique magnetometer module to make demining more precise than the current method of using off-road vehicles on land and special divers in coastal areas. It will also minimize the risk of injuries for the people involved, as the drone can be operated from a safe position outside the mined areas,” explains Arne Døssing, senior research, DTU Space, who heads the project of developing the new technology.
“It will be the first drone in the world to fly with a ‘bird’ underneath it. This construction is absolutely necessary to ensure the ultra-sensitive magnetometers are as close to the surface as possible, at the same time as minimizing exposure to magnetic disturbances from other instruments and from the flying drone,” says Døssing..
The drone has been developed by Sky-Watch, and in addition to the ability to fly like a regular aircraft, it allows for vertical take-off and landing in the same way as a helicopter.
Initially, the researchers will be focusing on the need to clear mines from World War II. The magnetometer drone will furthermore be tested in the mountains of Greenland, where it may have an impact on the search for mineral deposits or military waste, and it will also be tested from a vessel in relation to its ability to detect large mines in deeper waters. In both cases, the drone’s ability to take off and land vertically is significant.
Disruptor and drone combine to take on IED threats from the air
SteelRock Technologies and Chemring Technology Solutions have integrated Chemring’s RE70 M3 recoilless disruptor, which was originally designed to be deployed near the target by a bomb technician or mounted on a robot vehicle, with SteelRock’s W03 Protector UAV platform to create a revolutionary solution to neutralise improvised explosive devices (IEDs) in difficult-to-access environments. The companies have been trialling the hybrid platform for the past 18 months.
They selected the RE70 M3 disruptor, a commercial off-the-shelf item for Chemring. “It is excellent, there’s no other way to put it. They’ve done lots of really good homework making things very useable, robust – ‘soldier-proof’, dare I say it. It’s all about being intuitive and reducing training burden and something that actually works.”
There were some engineering challenges with the Chemring disruptor, which uses a counter mass systems; it fires a projectile out of the sharp end and dumps a load of water out the back at the same time. The timing’s clever because the recoil is effectively sum zero.
But there’s a big mass shift which is the real trick from the drone’s perspective because it’s carrying a payload that’s balanced with nearly a kilo of water at one end of it and a projectile at the other. So there’s that very quick mass shift and essentially gravity changes, and that’s what the drone is reacting to, not necessarily the recoil.
The developers found Aiming and getting the thing to tilt as the biggest challenge in getting the prototype working.
“It’s easy to make the projectile fly away from the drone, you just point it in the right direction, but the countermass comes directly out of the back. Depending on where you put that on the drone, that’s firing straight through the props, which is sub-optimal.”
“Aiming is quite interesting because you think flippantly we’ll stick the drone on hover and have an actuator arm that will do the up and down, and then just pan the drone left and right. But then you start to look into the control system software. It’s got an accuracy of between one and three degrees which, as you can shoot things up to 30m away with some of the Chemring projectiles, is quite a margin of error. We’re slowly honing that down to nice high levels of accuracy. It’s all about safety assurance.”
The system is espetially targetted to Military EOD/C-IED . “However, I see this platform or a variation on it being well-suited to humanitarian situations. Think of it this way: it’s a C-IED tool but has high-res cameras on board and so it can do reconnaissance and decent imagery, with potential for real-time 3D orthomosaic mapping. All of which are of varying importance in post-conflict zones and disaster areas.”