More than 100 million land mines are deployed throughout 70 countries around the world, some dating back to World War II. According to the United Nations, these devices kill or maim more than 2000 people each month.
In reaction to those alarming numbers, Carl V. Nelson, a principal staff physicist at the Johns Hopkins University Applied Physics Laboratory, devised a series of new sensors for landmine detection. But he needed a device that could safely carry these sensors into rugged terrain.
Four of the students in his Engineering Design Project course responded by developing a remote-control vehicle that finds landmines and marks their location. The front half of the vehicle contains two cordless power-drill motors that drive the robot. The drive segment also features a color video camera, so its operator can see whatever is encountered. The rear half houses a simple detection coil that the students took from a commercial off-the-shelf metal detector. Of course, production models would use more sophisticated sensors. And, the rear half contains a storage tank and a spray paint nozzle that marks the location of any mines it finds.
Operators maneuver the vehicle via a joystick on a battery-powered control, which features a color video screen that broadcasts images from the robot's camera. When the vehicle detects metal, the controller beeps. Operators then flip a switch on the control to activate the paint. The camera has a 100-foot broadcast range. The remote control has a range of about 500 feet.
Use of plastic and other non-metal parts in the vehicle's construction reduced costs and weight as well as improved upon the number of false positive readings. They spent about $5000 to design and build the prototype, though they estimate that the vehicle could be mass-produced for $1000 or less, based on the sophistication of the sensors. Nelson plans to show the prototype to his U.S. Army funding sponsors.
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