17-year-old girl inspired by piano invents land-mine detector

Seventeen-year-old Marian Bechtel has invented a prototype for a new land-mine-detection device that uses sound waves to identify where deadly mines are buried.

The invention earned her a spot as a finalist in the 2012 Intel Science Talent Search.

Land mines have been on Bechtel's mind since the eighth grade.

"My parents are both geologists," Bechtel tells Co.Exist. "Years ago they got connected with an international group of scientists working on a project called RASCAN, developing a holographic radar device for detecting land mines. During the summer before eighth grade, I met all of these scientists and talked with them about their work and the land mine issue. I was really touched and inspired by what they had to say, and wanted to get involved in science and possibly land mine detection."

The inspiration for her detection device came from an unlikely source: piano lessons.

"I noticed that when I played certain chords or notes on the piano, the strings on a nearby banjo would resonate," says Bechtel. "I heard this, and it was almost like the story of the apple falling on Newton's head — I thought that maybe I could use the same principle to find land mines. So, I began doing research and talking with scientists in humanitarian de-mining and acoustics; three years later I had built a prototype."

Bechtel was rewarded with a $25,000 fellowship from the Davidson Institute for Talent Development for her innovative creation:

"With Marian's method, two high-sensitivity, non-contact microphones are swept above buried land mines that resonate in response to a remote seismic source. The recorded sound is noise-cancelled in real-time, creating a characteristic, audible null in the noise-cancelled waveform that isolates the mine's location. This efficient and inexpensive method could make important contributions to humanitarian de-mining," the institute describes.

Watch the smart teen talk about war and peace below.