Noise – it’s everywhere, especially in cities. Traffic, trains, and neighbors often create an unwanted soundtrack to our lives.
Now, researchers from the Massachusetts Institute of Technology and other institutions may have developed a simple solution to noise pollution – silk.
In a new study, the research team details how it has created a new noise-canceling silk fabric, barely thicker than a single human hair, that suppresses sound using vibrations, according to SciTech Daily.
It cancels noise because of a special fiber that vibrates when voltage is applied and cancels sound in two ways, according to the study. In the first, the fabric generates sound waves that interfere with, and cancel out, unwanted noise, similar to noise-canceling headphones. The second method, and the one that makes the product viable for larger spaces, involves blocking the vibrations that transmit sound.
The team built upon their previous work using piezoelectric fiber to create fabric microphones. For the silk fabric, the group applied an electrical signal to the piezoelectric fiber, causing it to vibrate and generate sound. The researchers use a silk fabric loudspeaker to emit sound waves that interfere with the unwanted sound waves, canceling out noise.
The researchers chose to use silk, a common material that is very tightly woven, so the product would be easy to use, for example as dividers in rooms or on walls. This is a different approach to the usual methods of suppressing sound, said Yoel Fink, a senior author of the paper.
“Noise is a lot easier to create than quiet,” he noted. “In fact, to keep noise out we dedicate a lot of space to thick walls,” adding that this new fabric “provides a new mechanism for creating quiet spaces.”
To cancel our noise in larger spaces, the researchers also said they could control the vibrations in the fiber to force the fabric to remain still. “If we can control those vibrations and stop them from happening, we can stop the noise that is generated, as well,” said the study’s lead author, Grace Yang.
“There are a lot of knobs we can turn to make this sound-suppressing fabric really effective,” she added. “We want to get people thinking about controlling structural vibrations to suppress sound. This is just the beginning.”
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