Phys.org July 28, 2022 Aided by a reflecting surface, the acoustic carpet cloak has become one of the most practically feasible invisibility devices. However, due to the difficulty in the realization of ideal material parameters, the underwater carpet cloaks could only work for a small incident angle. Researchers in China designed an underwater carpet cloak using a three-component metafluid composed of syntactic foam, steel, and water. The syntactic foam, which is synthesized from epoxy resin and hollow glass microspheres, exhibits lower mass density and higher sound velocity relative to water. By periodically embedding the syntactic foam and steel rods in […]
Tag Archives: Acoustic cloaking
Scientists Built a New Kind of Invisibility Cloak, But It’s Not For Your Eyes
Science Alert September 4, 2021 An international team of researchers (Switzerland, UK) has achieved active acoustic cloaking and holography without prior knowledge of the wavefield so that objects remain invisible and illusions remain intact even for broadband moving sources. In the new approach, there’s a lot more versatility in making objects disappear – and it can even work the other way around to make it sound as if a non-existent object is taking up space in the room. FPGAs can respond to the audio speaker outputs with virtually no delay at all. So far, the researchers have managed to get […]