Roughly 20,000 people are maimed or killed each year due to land mines; the vast majority being civilians in parts of the world subject to ongoing conflict. Could a tag team of autonomous robots help solve the problem? That’s certainly what a team of roboticists from Worcester Polytechnic Institute in Massachusetts are hoping. They have spent the past half-decade developing an autonomous robot and sandbag-dropping drone which work together to seek and destroy potentially deadly land mines. And they’re almost ready for prime time.
As I’ve written before, collaborative robots are the future. Getting two (or potentially even more) different types of robot to work together means being able to combine the unique abilities of each and transform them into a cohesive solution that’s more than the sum of its parts. Have a slow, but steady rover which could methodologically sweep an area for mines using a metal detector, but has no way of getting rid of them? Have a drone with limited battery life and flight time which could be used to destroy mines by dropping something from above, while staying out of harm’s way? Get them talking to each other and suddenly you have a compelling partnership.
Robots working together
“It was always envisioned that [this project would feature] two different elements working together to solve the problem,” Craig Putnam, Senior Instructor in Robotics Engineering at Worcester Polytechnic Institute, told Digital Trends.
Well, kind of. In fact, the first iteration of the project — which dates back to 2014 — focused exclusively on the drone hardware. That year, WPI researchers set out to see if they could get a heavy lift DJI drone to autonomously navigate to a certain location, identify a makeshift marker on the ground using computer vision, and then release a payload. Aware of how much force it took to trigger a land mine and the ensuing shrapnel cone caused by the explosion, the researchers carried out experiments to work out the best height from which to drop these sandbags.
The rover was, at this point, “notional,” Putnam admitted. It was imagined as a provider of coordinates for the drone to visit — but it existed only in the minds of the people working on the project. “We pretended that the rover was out there finding the mines and marking them,” Putnam said.
With the drone component working, however, the researchers began to wonder what would happen if they actually built the rover robot they had been picturing. That was two years ago. The time ever since then has been dedicated to doing exactly that.
The rover the team has created isn’t entirely a homebrew creation. It builds on the body of a Clearpath Husky A100 rover, but makes several important additions. These include a special arm that holds a metal detector and a paint marking system which indicates to the drone where it should be targeting. Should the robot detect a mine, it paints a square around the deadly object, and then send its GPS coordinates to the drone, via a base station.
Most importantly, the researchers developed custom software that allow the two robots to talk to one another and carry out localization. This system boasts navigation algorithms which the rover uses to establish its search area by breaking it into a series of small grids and autonomously navigating to each one in turn.
“Ideally, the end goal of this project would be that someone sets up the base station and then does not need to enter the field again; the drone and rover can both run autonomously,” said Matthew Schmitt, one of the students working on the project. (Others include Joseph Niski and Karl Ehlers.)
A human operator would be required only when it came time to reload the drone with the non-reusable sandbags it carries as payload. Currently, the prototype is capable of carrying five, although that number could potentially be expanded in the future.
An affordable solution
This isn’t the only technology Digital Trends has covered when it comes to destroying land mines. For instance, in the past I’ve written about a “mine-munching tank” which weighs 30 tons and can chew through 50 tons of soil every hour. Any land mines it uncovers are ground harmlessly to bits between twins sets of rotating steel teeth called sizers. Military forces around the world have their own answers to the problem; typically in the form of large, reinforced tanks or bulldozers which can effectively clear areas of mines.
These technologies frequently work exceptionally well. But as Craig Putnam pointed out, they’re frequently inaccessible to small communities. The goal, he said, was “to come up with a system that was as low cost as reasonably possible, so that it could be afforded by some remote village that has a problem with land mines in the area. Military solutions tend to be extremely expensive. [For that reason] we were looking for something that mostly used off-the-shelf components … Ziplock bags [full of sand] and that kind of thing are very inexpensive.”
Right now, the project is still in the research and development stages. “We’re not testing with real land mines,” he explained.
The project will continue through spring, at which point he hopes that they will be “able to demonstrate that the whole thing is working as a system.” After that, Putnam hopes to get the Army “interested in further development and further testing.”
Should all go to plan, some time soon this innovative tag team of robots may well find its way to those who need it the most. Will it solve the land mine problem on its own? Of course not. But it could certainly help out. And when it comes to technology being used as a force for good in the world, that’s more than enough.
