Young Innovators: Detecting Land Mines All Things Considered host Robert Siegel speaks with Marian Bechtel, the 17-year-old inventor of a device that can detect land mines using sound waves. Earlier this year, Bechtel was awarded a fellowship from the Davidson Institute for Talent Development.

Young Innovators: Detecting Land Mines

Young Innovators: Detecting Land Mines

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All Things Considered host Robert Siegel speaks with Marian Bechtel, the 17-year-old inventor of a device that can detect land mines using sound waves. Earlier this year, Bechtel was awarded a fellowship from the Davidson Institute for Talent Development.


To another big idea now, this one from a remarkably young mind. All this week, we're profiling young innovators who've already made advances in the fields of science and technology before they're even old enough to vote.

Today, Marian Bechtel. She's a 17 year old from Lancaster, Pennsylvania, and she has invented a new and inexpensive minesweeper. The twist on this device? It detects mines using sound.


SIEGEL: That's a recording of the prototype minesweeper as it detects an object on Bechtel's porch and Marian Bechtel joins us now on the line. Welcome to the program.


SIEGEL: And tell us how you came up with this idea.

BECHTEL: I actually came up with this idea when I was in eighth grade. I was playing the piano - I'm a musician - and I was in my music room playing the piano and there's a banjo that hangs on the wall nearby. And I'd play certain chords or notes and I noticed that the banjo strings would resonate and so I thought, hey, maybe I can use this principle to detect buried mines.

So I started doing the research and, three years later, I ended up with a prototype.

SIEGEL: Obviously, it would be impractical to take a grand piano and wheel it through the mine field to detect with.

BECHTEL: Yes, obviously.

SIEGEL: What did you actually do?

BECHTEL: I actually used - in my test, I used a concrete vibrator. It's something that's usually used to get bubbles out of drying concrete, so you just stick it in the ground and it just sends seismic waves through the ground and that makes any buried land mines in the area resonate.

SIEGEL: A minesweeper is a tricky instrument to test. Do we know that it would actually find a mine? I wouldn't want to be the test subject.

BECHTEL: Yeah. Well, actually, I do have real land mine casings without the explosives to test with. I also used - I made mock land mines out of candy tins and filled them with RTV silicone rubber and tested those.

SIEGEL: I hope your success rate was 100 percent.


BECHTEL: Yes. For the most part. Yeah.

SIEGEL: For the most part?


BECHTEL: Well, I mean, I did get some false alarms with, like, tuna cans.

SIEGEL: I see. False positives?

BECHTEL: Yeah, yeah.

SIEGEL: Now, many people your age are not especially interested and let alone aware of land mines. What sparked your interest here?

BECHTEL: Well, actually, I'm kind of lucky because both of my parents are scientists and they have actually become really good friends with a group of international scientists that developed a holographic radar device for detecting land mines. And so all of these scientists came to our house one year and we were basically sitting on our floor playing cards and I was really inspired by what they had to say. So as all of this was running through my head, then the whole piano/banjo thing happened and I made the connection.

SIEGEL: Have your scientific interests and your interests in making the minesweeper, have they clashed with your school activities at all or have they enhanced your school activities?

BECHTEL: Well, I'd say actually the science that I've done and the science fairs that I go to with my project, I've learned as much, if not more, from those than I have in school. Except actually one instance where it did clash recently was I was recently named a finalist for the Siemens science competition and the date for the competition was actually the same day as my marching band championships and I was really stressed because I couldn't choose which love to go with, science or music.

But I eventually ended up going with music because I was a section leader and a really devoted member to the marching band.

SIEGEL: Please tell me you don't play piano in the marching band.

BECHTEL: No, no, no. I play trumpet in the marching band.

SIEGEL: That's much more practical.


SIEGEL: What are your ambitions, Marian?

BECHTEL: I'm not exactly sure what I want to do with my life, but I've told people before that my dream is to do particle physics and work at CERN in Switzerland, but definitely, I want to do something in science.

SIEGEL: Well, we wish you the best and congratulations.

BECHTEL: Thank you.

SIEGEL: That's Marian Bechtel speaking to us from Lancaster, Pennsylvania. She was recently awarded a fellowship from the Davidson Institute for Talent Development for her invention of a minesweeper.

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