Finding Land Mines Faster

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TR: Many of the things you and your students have worked on -- the probe, a magnetic rake, protective gear -- are low-tech. Wouldn't devices that use autonomous or remote-sensing elements in some cases be more effective and safer?

AH: There are places for mechanized demining, but the best results are often making small changes to existing equipment that can then be built and used by anyone. Let's say you're in Angola and your robot's 9-volt battery dies: Where are you going to get a new one? Or Windows crashes -- who's going to know how to reboot it? I saw a demonstration once with a sensor that used a keyboard. It got sand in it -- and that was the end of the trial.

Also, there's variation from area to area -- rocks, trees, river banks. It's not like the image of a golf course that's been mined.

Secondly, you employ a lot of people [with handheld tools]. A deminer in Afghanistan earns $120 a month, so you can have 1,000 people working for the cost of a piece of expensive machinery.

As far as safety, a deminer will have an accident about every 30 years -- it's safer than driving a taxi in many of these places. If someone is properly trained and wears a $40 face visor and Kevlar blast vest, he'll walk away from an accident with minor hearing damage for a couple of weeks.

One of the most important things [in demining] is the hand-over ceremony. A local community has to believe their land is clean -- or it's a waste of time. After the deminers are done, they will link arms and walk across the field -- and then they start playing soccer on it. The community joins in, and it becomes a big party. Would you play soccer behind a robot?

TR: Another tool you've worked on is a "mag" rake? What is it?

AH: A big problem in demining is false positives: for every land mine there can be 1,000 metal fragments [in a field]....This is the most tedious, boring work you can imagine. Our goal is to use the deminer in the best possible way: not digging at fragments, but at a dangerous mine. A rake with magnets on it could pick up surface fragments, saving a lot of time. You would kneel behind it and "tickle" the ground.

We did studies that showed there are situations when a rake makes sense. Now the big question is: How do you build one that will not blow apart if there's an accident? The last thing you want is to add more shrapnel to a mine field.

TR: Another of your current projects also addresses false positives. And it's also a lot more complex: redesigning a military mine detector so it's affordable for individual deminers. Can you describe that effort?

AH: Well, we're still negotiating, but a nonprofit group, Benetech, contacted us on a project where they've licensed U.S. military technology for detecting nitrogen bonds in explosives. It uses what's called Quadrupole Resonance (QR) technology that identifies explosive material using radio frequency. The device can also detect low-metal mines. They want to make a stripped-down, low-cost version of it, for around $2,000, instead of $60,000. If such a device can be made, deminers wouldn't have to dig up all the false positives. It might speed up [humanitarian] demining by a factor of 10.

We plan to work with Benetech on incorporating their design for a lower-cost sensor, which looks feasible, into a machine that can be carried by an individual.

TR: What do you see yourself doing 10 years from now?

I really like product design -- inventing things and designing products. But I don't really want to design a better toaster....Demining is still early in its product curve; things we do can actually make a difference.