Month: September 2022

FRENCH SCIENTISTS "carried out the largest-scale test to date of seismic metamaterials. The reported experimental results are encouraging: an artificial structure built around a target can be used to deflect incoming acoustic waves at a frequency relevant to earthquake protection. This preliminary success in the laboratory could one day translate into a way of mitigating the destructive effects of earthquakes." https://lnkd.in/edaQCe9 View in LinkedIn

IT'S ALL ABOUT WAVES. "Sound waves move much like light waves. They travel on a straight path but this path – through reflection, diffraction or refraction – can be bent. This is the basis for ultrasound medical imaging and non-destructive testing of materials." https://lnkd.in/eN74kab View in LinkedIn

SOUND CLOAKING. "The acoustic cloaking device works in all three dimensions, no matter which direction the sound is coming from or where the observer is located, and holds potential for future applications such as sonar avoidance and architectural acoustics." https://lnkd.in/bPE7nGe View in LinkedIn

FIRST ACOUSTICAL CLOAK (2014). "Using little more than a few perforated sheets of plastic and a staggering amount of number crunching, Duke engineers have demonstrated the world’s first three-dimensional acoustic cloak. The new device reroutes sound waves to create the impression that both the cloak and anything beneath it are not there." https://lnkd.in/bPE7nGe View in LinkedIn

SECOND ACOUSTICAL CLOAK (2014). Berkeley's acoustic bottle. "“We can also use an acoustic bottle as a cloaking device, re-routing sound waves around an object and then recovering them in their original form, making the object invisible to sonar detection." https://lnkd.in/eN74kab View in LinkedIn

DARPA, of course, is interesting in acoustic cloaking for military applications. "This effort will use directed ultrasound technology to enable the capability to significantly reduce sound emissions from large scale tactical military hardware." https://lnkd.in/bZG9Gkr View in LinkedIn

ACOUSTIC LEVITATION "is a method for suspending matter in a medium by using acoustic radiation pressure from intense sound waves in the medium. Sometimes ultrasonic frequencies can be used to levitate objects, thus creating no sound heard by the human ear, such as was demonstrated at Otsuka Lab, while others use audible frequencies." https://lnkd.in/e2nki6q View in LinkedIn

"ACOUSTIC BOTTLE BEAMS might also serve another application that ranks among the hottest in the high-tech community these days – acoustic levitation, in which sound waves are used to lift and manipulate millimeter-sized objects, including particles, microorganisms and droplets of water." https://lnkd.in/eN74kab View in LinkedIn

BREAKTHROUGH. "A recent study reporting the use of standing sound waves for 3D graphic printing was hailed as a major breakthrough." https://lnkd.in/eN74kab View in LinkedIn

VIDEO of acoustic levitation. https://lnkd.in/eDebiSY View in LinkedIn