Local resonance coding sensing metamaterial system for broadband weak vibration sensing

Abstract

A local resonance coding sensing metamaterial system for broadband weak vibration sensing consists of at least one metamaterial supercell module with adjustable coding. Each metamaterial supercell module includes a plurality of metamaterial unit cells arranged in an array. Each metamaterial unit cell comprises a substrate, an elastic element disposed at the center of the substrate, and a transducer block disposed perpendicular to the center of the elastic element. Multiple periodically arranged metamaterial unit cells form a planar metamaterial supercell module. This invention utilizes a broadband enhanced coding method using local oscillator frequency division multiplexing, combining local resonance coding technology with computational sensing strategies. This system achieves enhanced perception of broadband vibration information within a bandwidth of 0-12.5kHz while offering advantages such as modular structure, compact size, low cost, wide operating frequency band, high sensitivity, and flexible control.

Description

Technical Field

[0001] The present invention relates to a technology in the field of broadband weak vibration sensing, specifically a local resonance coding sensing metamaterial system for broadband weak vibration sensing. Background Art

[0002] Broadband weak vibration sensing has a wide range of applications in precision mechanical engineering, aerospace engineering, and deep-sea exploration engineering. In many complex situations, achieving enhanced perception of weak vibrations within a wide frequency range is a technical challenge. Currently, local resonant metamaterials have been developed and applied to enhanced perception of elastic waves due to their subwavelength-scale elastic wave manipulation properties, to achieve the design of elastic wave sensing structures with small size and light weight. Among the methods for elastic wave sensing, traditional local resonant metamaterial technology mainly designs the dynamic equivalent parameters of the structure, that is, by changing the negative equivalent mass or negative equivalent modulus of the structure to achieve flexible manipulation of the elastic wave transmission characteristics. These methods are currently mainly limited to enhanced perception in the field of acoustic waves, and are still in their infancy in the field of vibration sensing. In particular, there is still a large technical gap in how to achieve enhanced perception of broadband vibrations in the range of several Hz to tens of kHz. In piezoelectric accelerometers commonly used for vibration signal measurement, traditional vibration sensing strategies are mainly based on non-resonant designs. In these traditional structural designs, weak vibration signals are not enhanced, so it is difficult for the sensor device to achieve both high sensitivity and broadband sensing characteristics. This greatly limits its application in weak vibration sensing in extreme environments, such as early fault diagnosis of mechanical equipment and remote abnormal vibration monitoring. Summary of the Invention

[0003] In response to the problem that existing non-resonant vibration sensors cannot achieve both high sensitivity and broadband perception characteristics, the present invention proposes a local resonance coding perception metamaterial system for broadband weak vibration sensing. It adopts a broadband enhanced coding method of local oscillator frequency division multiplexing, combines local resonance coding technology with computational perception strategy, and realizes enhanced perception of broadband vibration information in the bandwidth range of 0-12.5kHz. At the same time, it has the advantages of modular structure, small size, low cost, wide operating frequency band, high sensitivity, and flexible regulation.

[0004] The present invention is achieved through the following technical solutions:

[0005] The present invention relates to a local resonance coding sensing metamaterial system for broadband weak vibration sensing, which is composed of at least one metamaterial supercell module with adjustable coding. Each metamaterial supercell module includes: a plurality of metamaterial unit cells arranged in an array manner. Each metamaterial unit cell includes: a substrate, an elastic element arranged at the center of the substrate, and a transducer block arranged perpendicular to the center of the elastic element. Multiple metamaterial unit cells arranged in an orderly manner in a periodic manner constitute a metamaterial supercell module with a planar structure.

[0006] The adjustable coding refers to: the elastic parameters of the elastic element and the mass parameters of the transducer block are preset in each metamaterial unit cell, and multiple metamaterial units form a customized spring-mass-damper mechanism.

[0007] The preset is preferably based on the resonance frequency of each metamaterial unit cell being evenly distributed in a decade within the range of 0-12.5 kHz and being different from each other.

[0008] The period refers to that each metamaterial unit cell is periodically arranged in a metamaterial supercell in a layer arrangement, a column arrangement, a ring arrangement or a spatial mosaic combination, and there is no limit on the number of periodic arrangements of the metamaterial units.

[0009] The order mentioned above means that, based on the periodic arrangement, the metamaterial unit cells at each position in the supercell are distributed in order in the supercell according to the decimal coding method of code 1 to code 9.

[0010] The elastic element is realized by, but not limited to, an elastic beam, rubber and a spring.

[0011] The vibration output position of each metamaterial unit cell in the local resonance coding sensing metamaterial system, that is, the top of the elastic element at the center of the unit cell matrix is ​​provided with a transducer that converts the vibration signal into an electrical signal.

[0012] The local resonance coding perception metamaterial system is further provided with a signal processor, which collects the vibration signals output by all metamaterial cells and realizes broadband enhanced coding of local oscillator frequency division multiplexing through perception reconstruction calculation.

[0013] The metamaterial supercell module is made of, but not limited to, metal, plastic, rubber, etc. using manufacturing methods such as 3D printing, laser cutting, CNC machining, and gluing.

[0014] The present invention relates to a broadband enhanced encoding method for the vibration information of a metamaterial system based on the above-mentioned local resonance coding perception. A transducer is used to convert the resonance signals of different preset metamaterial units into electrical signals, thereby synchronously collecting multi-channel vibration signals and realizing enhanced perception and reconstruction of broadband vibration information through multi-channel demodulation.

[0015] The multi-channel demodulation mentioned above refers to: filtering and noise reduction processing of the electrical signal of each resonance signal, and demodulating the vibration signal modulated by the local resonance coding sensing metamaterial through adaptive minimum mean square value; the working frequency bands of each unit cell channel do not overlap with each other, and the working frequency bands of multiple unit cells are fused through a multi-channel fusion strategy, thereby realizing the demodulation and reconstruction of the broadband vibration signal.

[0016] Technical Effects

[0017] The present invention achieves highly sensitive sensing of broadband vibration signals through a resonant local resonance coding metamaterial design, which comprehensively solves the problem that existing non-resonant vibration sensors cannot take into account both high sensitivity and broadband perception characteristics. It realizes enhanced perception of broadband vibration information in the bandwidth range of 0-12.5kHz, and improves the sensitivity by two orders of magnitude compared with non-resonant sensing designs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of a metamaterial unit cell of the present invention;

[0019] Figure 2 This is a schematic diagram of a metamaterial supercell module of the present invention;

[0020] Figure 3 Schematic diagram of the overall system of the present invention;

[0021] In the figure: metamaterial unit cell 1, matrix 101, elastic element 102, transducer block 103, supercell module 2, local resonance coding sensing metamaterial system 3. DETAILED DESCRIPTION

[0022] like Figure 1 As shown, this embodiment relates to a local resonance coding sensing metamaterial system for broadband weak vibration sensing, which is composed of at least one metamaterial supercell module with adjustable coding. Each metamaterial supercell module includes: a plurality of metamaterial cells 1 arranged in an array manner, each metamaterial cell 1 includes: a substrate 101, an elastic element 102 arranged at the center of the substrate 101, and a transducer block 103 vertically arranged at the center of the elastic element 102. A cylindrical counterweight block is provided on the top of the transducer block 103. Multiple periodically arranged metamaterial cells constitute a metamaterial supercell module with a planar structure.

[0023] The supercell module 2 can be manufactured by 3D printing, laser cutting, CNC machining, gluing, etc., and can be made of metal, plastic, rubber, etc. The metamaterial system 3 can also be manufactured by a structural integration manufacturing method.

[0024] The output end of the transducer block of the local resonance coding sensing metamaterial system converts the vibration signal into an electrical signal and is connected to a data acquisition system for collecting voltage signals.

[0025] The metamaterial unit cell 1 can customize the dynamic parameters according to the coding strategy, and the composed supercell module 2 can produce customized zero equivalent mass within a wide frequency range. The local resonance coding perception metamaterial system 3 horizontally connected through the supercell module 2 realizes multiple resonance enhanced perception of out-of-plane vibrations.

[0026] In this embodiment, the metamaterial unit cell 1 is designed as a "spring-mass-damper" resonant system. The metamaterial unit cells 1 are arranged in a coded order within the supercell module 2. Horizontally adjacent supercell modules 2 are connected to form a localized resonant coded sensing metamaterial system 3. This coded sensing metamaterial system 3 can be combined into various linear, surface, and volume configurations as needed. The metamaterial unit cells 1 within the supercell module 2 are arranged periodically according to the coded sequence, and the coding scheme of the metamaterial unit cells 1 between different supercell modules 2 is customized based on the vibration sensing frequency band.

[0027] This embodiment does not impose any specific limitations on the shape structure of the metamaterial unit cell 1 , the coding arrangement of the metamaterial unit cell 1 , the shape structure of the supercell module 2 , the arrangement and placement of the supercell module 2 , and the configuration of the metamaterial system 3 .

[0028] Through specific practical experiments, the vibration sensing performance of the metamaterial system was verified in the specific environment of an engineering laboratory, with a supercell thickness of 2.5 mm and an area of ​​9 square centimeters. Vibration signals were triggered within the 0-12.5 kHz range, and multi-frequency vibration signals were measured within a -20 dB signal-to-noise ratio range. The average reconstruction error of a single harmonic was less than 3%. The data verification shows that the present invention as a whole achieves enhanced coded perception of broadband weak vibration information.

[0029] Compared with the existing non-resonant vibration sensing technology that cannot achieve both high sensitivity and broadband sensing characteristics within the wide frequency range below 12.5kHz, this system can achieve broadband weak vibration sensing with a sensitivity increased by 2 orders of magnitude within the wide frequency working range below 12.5kHz, and realize the enhanced perception function of micro-motion under the strong noise background in extreme environments. It has high sensing sensitivity, wide working range, good adaptability to strong noise background, and has the advantages of small size, low cost, easy modularization, and easy improvement.

[0030] The above-mentioned specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principles and purpose of the present invention. The scope of protection of the present invention shall be based on the claims and shall not be limited by the above-mentioned specific implementation. All implementation schemes within its scope shall be subject to the constraints of the present invention.

Claims

1. A local resonance coding sensing metamaterial system for broadband weak vibration sensing, characterized in that: It is composed of at least one metamaterial supercell module with adjustable coding, each metamaterial supercell module includes: a plurality of metamaterial unit cells arranged in an array, each metamaterial unit cell includes: a substrate, an elastic element arranged at the center of the substrate, and a transducer block arranged perpendicular to the center of the elastic element. Multiple metamaterial unit cells arranged in an orderly manner in a periodic manner constitute a metamaterial supercell module with a planar structure; The coding adjustment mentioned above refers to: the elastic parameters of the elastic element and the mass parameters of the transducer block preset in each metamaterial unit cell, and multiple metamaterial units form a customized spring-mass-damper mechanism; The preset is based on the resonant frequency of each metamaterial unit cell being evenly distributed in a decade within the range of 0-12.5 kHz and being different from each other; The order mentioned above means that: on the basis of periodic arrangement, the metamaterial unit cells at each position in the supercell are orderly distributed in the supercell in the manner of code 1 to code 9; The local resonance coding perception metamaterial system collects the output vibration signals of all metamaterial cells through a signal processor, and realizes broadband enhanced coding of local oscillator frequency division multiplexing through perception reconstruction calculation.

2. The local resonance coding sensing metamaterial system according to claim 1, characterized in that: The period refers to that each metamaterial unit cell is periodically arranged in a metamaterial supercell in a layer arrangement, a column arrangement, a ring arrangement or a spatial mosaic combination, and there is no limit on the number of periodic arrangements of the metamaterial units.

3. The local resonance coding sensing metamaterial system according to claim 1, characterized in that: The elastic element is realized by using elastic beams, rubber and springs.

4. The local resonance coding sensing metamaterial system according to claim 1 or 2, characterized in that: The vibration output position of each metamaterial unit cell, that is, the top of the elastic element at the center of the unit cell matrix, is equipped with a transducer that converts the vibration signal into an electrical signal.

5. A broadband enhanced coding method based on the local resonance coding sensing metamaterial system according to any one of claims 1 to 4, characterized in that: A transducer is used to convert the resonance signals of different preset metamaterial cells into electrical signals, so as to synchronously collect multi-channel vibration signals and realize enhanced perception and reconstruction of broadband vibration information through multi-channel demodulation.

6. The broadband enhanced coding method according to claim 5, wherein: The multi-channel demodulation mentioned above refers to: filtering and noise reduction processing of the electrical signal of each resonance signal, and demodulating the vibration signal modulated by the local resonance coding sensing metamaterial through adaptive minimum mean square value; the working frequency bands of each unit cell channel do not overlap with each other, and the working frequency bands of multiple unit cells are fused through a multi-channel fusion strategy, thereby realizing the demodulation and reconstruction of the broadband vibration signal.

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