- Researchers at the Lawrence Berkeley National Laboratory in California developed the ‘acoustic bottle’ to make objects invisible to sonar detection
- Bottle is made up of high acoustic pressure around zero pressure region
- Sound from speakers is directed in a specific way to create bottle shape
- The force of the outer shell can also be used to levitate objects such as particles and drops of water
Sound waves may not appear to hold much power, but scientists believe directing them in the right way could allow them to hide objects and even levitate them in the air.
Researchers in the US have developed technology to manipulate sound waves on fixed paths around an acoustic ‘bottle’.
The technique could be used to re-route sound waves around an object making them invisible to sonar detection.
This animation shows the self-bending and obstacle-circumventing capabilities of the acoustic bottle compared to a conventional beam (top). Sound energy can be seen flowing through the shell of the bottle
The acoustic bottle could also help in levitation, where sound waves are used to lift and manipulate objects like particles, micro-organisms and drops of water.
Researchers at the Lawrence Berkeley National Laboratory in California developed the acoustic bottle, which is a three dimensional structure made up of high pressure acoustic waves.
These acoustic bottles in open air can bend the paths of sound waves along preplanned paths.
PLASTIC PYRAMID ACTS AS AN INVISIBILITY CLOAK FOR SOUND
It might look like a quirky plastic model of an ancient Egyptian pyramid, but this model is in fact a 3D ‘acoustic cloak’, created using just a few perforated sheets of plastic.
The device reroutes sound waves to create the impression that both the cloak and anything beneath it are not there.
Like the ‘acoustic bottle’, a refined version of the technology could one day be used for sonar avoidance and to refine noise in concert halls.
Engineers from Duke University in North Carolina, claim that unlike other efforts, the acoustic cloaking device works in all three dimensions, no matter which direction the sound is coming from.
‘The particular trick we’re performing is hiding an object from sound waves,’ said Steven Cummer, professor of electrical and computer engineering.
The pyramid is constructed using plastic plates with a repeating pattern of holes that are stacked on top of one another. Its design means that sound waves can be manipulated by plastic and air.
The cloak alters the sound waves’ trajectory to match what they would look like had they had reflected off a flat surface.