When you or I go shopping for noise-cancelling headphones, we imagine ourselves listening to music in blissful quiet stripped of traffic noise and seatmate chatter. But Christopher Nguyen has something much bigger in mind. He wanted to use the technology to silence a 1-ton church bell.
Nguyen studies biomedical engineering at the University of Wisconsin-Madison. What set him on his way was the phrase “You can’t un-ring a bell,” meaning that it’s impossible to undo something once it has been done. It was the perfect fit for the second edition of GE’s open innovation challenge Unimpossible Missions called The University Edition. Earlier this year, the company invited students from around the world to prove idioms of improbability wrong with GE technology. Nguyen is the first student winner of this competition.
GE launched the first installment of “Unimpossible Missions” last fall. It challenged GE scientists to improve a snowball’s chance in hell, capture a lightning in a bottle and talk meaningfully to a wall. Nguyen’s journey begun when he was trying to choose the right pair of noise-cancelling headphones. “I started to wonder, ‘How do these actually work?’” he says. He wanted to know if he could silence a loud brass bell that rings in the key of G in a stone church tower.He figured that entering the challenge would be a good way to start. In his winning submission, he proposed applying special foam to isolate the bell’s ring and eliminate unwanted echoes. Then, microphones and GE’s subsea acoustics systems would help him analyze the exact frequency and amplitude of the bell. Finally, he would deploy an approach called destructive interference to play the bell’s exact same soundwave, but with an inverse phase. He would broadcast that sound from 256-watt, 114-decibel loudspeakers positioned around the bell, let the two opposite soundwaves collide and cancel each other out. The end result would be absolute silence.
GE scientists saw the potential in his idea and decided to build on it. For the past month they’ve been conducting tests in the GE Global Research labs in Niskayuna, New York. Next, the Unimpossible Missions team will take the experiment to the site of an ancient bell—the plan includes locations in Greece, Myanmar or Nepal—and test the technology in the field. To prove their point, engineers plan to place a sleeping baby in a crib while ringing the bell. Assuming all goes as planned, the baby will remain blissfully unaware of the experiment.
Sounds like fun, but such noise-calling technology has a range of practical applications. It could make MRI machines quieter or help jet engines burn fuel more efficiently.
As the grand prizewinner, Nguyen will receive a scholarship worth up to $100,000 to continue his Science, Technology, Engineering and Mathematics (STEM) courses, as well as 10-week paid internship next summer working next to GE scientists and researchers at GE Global Research. Two other students will also be awarded 10-week paid internships for their entries.
Tanusha Goswami, a student at India’s Manipal Institute of Technology, Manipal University, focused on the Spanish saying “Cuando llueva pa’ arriba” (When rain falls upwards). Her experiment used magnetic fields to make water drops fall in the opposite direction. Virginia Tech student Kevin Dennis tackled the idiom “Hanging by a thread.” His experiment hangs a car from a thread made of GE’s polymer matrix composites, showing the tremendous strength of the new material.
The original challenge began among GE scientists in honor of Thomas Edison’s birthday. It was aimed at proving that — scientifically speaking — the “impossible” was possible. Those experiments became a three-part video series called “Unimpossible Missions.”
Earlier this year, GE extended the same challenge to students, in partnership with GENIUSLINK and the open innovation platform NineSigma. GE received more than 575 entries from 375 schools around the world. “Our scientists and engineers want to pass their knowledge on to the next generation,” says Vic Abate, GE’s chief technology officer. “This contest was aimed at inspiring students to think big, push the boundaries of what is possible and ultimately pursue a career in science and technology.”
Nguyen is now considering going to graduate school to study engineering instead of applying to medical school. At a recent visit to GE, he met an engineer working on tiny robots that go inside jet engines to make repairs without having to take the engine apart. “That really spurred my curiosity,” Nguyen says.