Acoustic wave cloaking method and device considering generalized time dependency

Patent metadata

Field	Value
Publication number	US-10460713-B2
Application number	US-201615383824-A
Country	US
Kind code	B2
Filing date	Dec 19, 2016
Priority date	Aug 29, 2014
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

Disclosed herein are a method and device for cloaking an acoustic wave. A method for cloaking an acoustic wave according to an embodiment of the present invention includes: transforming an acoustic propagation mathematical model, predetermined for the propagation of an acoustic wave, into an acoustic wave cloaking mathematical model corresponding to an electromagnetic wave mathematical model predetermined for an electromagnetic wave and including a time variable for time dependency, based on a correlation between the acoustic propagation mathematical model and the electromagnetic wave mathematical model; obtaining a target characteristic of a meta-material by using the acoustic wave cloaking mathematical model; and blocking a region including a target object, from an acoustic wave by disposing the meta-material having the obtained target characteristic to surround the region.

First claim

What is claimed is:

1. A method of cloaking an acoustic wave, comprising:
transforming an acoustic propagation mathematical model, predetermined for propagation of an acoustic wave, into an acoustic wave cloaking mathematical model corresponding to an electromagnetic wave mathematical model predetermined for an electromagnetic wave and including a time variable for time dependency in a 4D coordinate system, based on a correlation between the acoustic propagation mathematical model and the electromagnetic wave mathematical model;
obtaining a target characteristic of a meta-material by using the acoustic wave cloaking mathematical model; and
blocking a region including a target object, from an acoustic wave by disposing the meta-material having the obtained target characteristic to surround the region,
wherein a target characteristic of the meta-material is calculated based on a space-time meta-material analysis based on the General Theory of the Relativity,
wherein an empty space of a physical space corresponding to the target region to be hidden with the target object is transformed into a virtual space that has a point the empty space of the physical space is transformed thereto, so that the empty space of the physical space is hidden from external acoustic waves, and
where the transformation of the physical space into the virtual space is obtained using covariant Maxwell's equations based on the General Theory of the Relativity, and using a coordinate transformation equation according to a spatial topology of the target region and the meta-material.

2. The method of claim 1 , wherein the transforming comprises obtaining a one-to-one correspondence between acoustic propagation parameters of the acoustic propagation mathematical model and electromagnetic wave parameters of the electromagnetic wave mathematical model, and transforming the acoustic propagation mathematical model into the acoustic wave cloaking mathematical model by using the one-to-one correspondence between the acoustic propagation parameters and the electromagnetic wave parameters.

3. The method of claim 1 , wherein:
the electromagnetic wave mathematical model comprises a Maxwell's equations-based mathematical model; and
the transforming comprises transforming the acoustic propagation mathematical model into the acoustic wave cloaking mathematical model by applying the acoustic propagation mathematical model into a Maxwell's equations-based relativistic coordinate-space transformation method.

4. The method of claim 1 , wherein the acoustic wave cloaking mathematical model is a mathematical model that is applicable to all coordinate systems including an elliptic coordinate system, a bipolar coordinate system, a Cartesian coordinate system, a cylindrical coordinate system, and a spherical coordinate system.

5. A device for cloaking acoustic wave by using a meta-material, wherein:
the meta-material has a target characteristic obtained using a predetermined acoustic wave cloaking mathematical model, and is disposed to surround a target region including a target object to be blocked from an acoustic wave; and
the acoustic wave cloaking mathematical model is determined through transformation of an acoustic propagation mathematical model predetermined for propagation of an acoustic wave in accordance with an electromagnetic wave mathematical model predetermined for an electromagnetic wave based on a correlation between the acoustic propagation mathematical model and the electromagnetic wave mathematical model, and includes a time variable for time dependency in a 4D coordinate system,
wherein a target characteristic of the meta-material is calculated based on a space-time meta-material analysis based on the General Theory of the Relativity,
wherein an empty space of a physical space corresponding to the target region to be hidden with the target object is transformed into a virtual space that has a point the empty space of the physical space is transformed thereto, so that the empty space of the physical space is hidden from external acoustic waves, and
where the transformation of the physical space into the virtual space is obtained using covariant Maxwell's equations based on the General Theory of the Relativity, and using a coordinate transformation equation according to a spatial topology of the target region and the meta-material.

6. The device of claim 5 , wherein the acoustic wave cloaking mathematical model is transformed from the acoustic propagation mathematical model by using a one-to-one correspondence between acoustic propagation parameters of the acoustic propagation mathematical model and electromagnetic wave parameters of the electromagnetic wave mathematical model obtained based on the correlation between the acoustic propagation mathematical model and the electromagnetic wave mathematical model.

7. The device of claim 5 , wherein:
the electromagnetic wave mathematical model comprises a Maxwell's equations-based mathematical model; and
the acoustic wave cloaking mathematical model is determined through the transformation of the acoustic propagation mathematical model by applying the acoustic propagation mathematical model into a Maxwell's equations-based relativistic coordinate-space transformation method.

8. The device of claim 5 , wherein the acoustic wave cloaking mathematical model is a mathematical model that is applicable to all coordinate systems including an elliptic coordinate system, a bipolar coordinate system, a Cartesian coordinate system, a cylindrical coordinate system, and a spherical coordinate system.

Assignees

• Univ Seoul Ind Coop Found

Inventors

• Ahn Do Yeol

Classifications

• G06F17/16

  Matrix or vector computation {, e.g. matrix-matrix or matrix-vector multiplication, matrix factorization (matrix transposition G06F7/78)} · CPC title

• G10K11/162 Primary

  Selection of materials · CPC title

• G06F17/11

  for solving equations {, e.g. nonlinear equations, general mathematical optimization problems (optimization specially adapted for a specific administrative, business or logistic context G06Q10/04)} · CPC title

• G10K11/16

  Methods or devices for protecting against, or for damping, noise or other acoustic waves in general (G10K11/36 takes precedence) · CPC title

• G10K15/00

  Acoustics not otherwise provided for · CPC title