A bionic binary array sound direction-finding acquisition unit and sensor based on the hearing of Omnia caesar

Abstract

A bionic binary array sound direction acquisition unit based on the hearing of Ormia ochracea and a sensor using the acquisition unit, which relates to the technical field of bionic sound direction array sensors. It solves the defect that the existing sound direction sensors are too large in volume under the premise of ensuring accuracy. The bionic sound direction binary array sensor of the present application is based on the principle of keratin coupling between the two eardrums of Ormia ochracea. The acquisition unit in the sensor is composed of two rectangular diaphragms fixed at one end and a coupling diaphragm located in the middle of the two rectangular diaphragms. According to the coupling amplification mechanism of the hearing of Ormia ochracea, an F-P resonant cavity is formed by using optical fibers and the two element diaphragms, so as to realize the large amplification of the tiny time delay of the vibration between the two element diaphragms by using optical signals. The binary array sound direction acquisition unit and the sensor realize the miniaturization of traditional instruments. It can be widely applied to miniaturized intelligent information platforms such as unmanned aerial vehicles, unmanned boats and intelligent robots.

Description

Technical Field

[0001] The present invention relates to the technical field of bionic sound direction array sensors. Background Art

[0002] Sound direction sensor technology is a new technology that has gradually emerged and developed rapidly with the development of sound pressure sensor arrays and array signal processing technology, combined with MEMS technology and sensor detection technology. It has broad application and development prospects in small intelligent information platforms such as unmanned aerial vehicles, unmanned boats, and intelligent robots.

[0003] The current sound direction technology deploys multiple sound pressure sensors at different positions in space to form an array. By using the phase difference or time delay of the signals received by different array element sensors, combined with the relative position relationship of the array elements in space and the signal frequency, the incident angle of the sound signal is calculated through array signal processing and direction-of-arrival estimation methods to orient the sound source direction. The orientation accuracy mainly depends on two factors: the estimation accuracy of the phase difference or time delay between the signals received by the array elements and the sensitivity of the phase difference or time delay to the direction-of-arrival angle. The sensitivity of the phase difference or time delay to the direction-of-arrival angle is restricted by the ratio of the array aperture to the signal wavelength. The smaller the ratio of the array aperture to the signal wavelength, the lower the sensitivity. Since sound waves have a very long wavelength, a large array aperture is required to ensure accuracy, so it is difficult to miniaturize the orientation device. Summary of the Invention

[0004] The technical problem solved by this application is that in the current sound direction technology field, to obtain higher orientation accuracy, a large array aperture is required, resulting in a large volume of the orientation device and unable to achieve miniaturization. The technical solution adopted by the present invention is:

[0005] A bionic binary array sound direction acquisition unit based on the hearing of Ormia ochracea, the acquisition unit includes: a sound wave acquisition unit 13 and a base 10, the sound wave acquisition unit 13 includes a support structure 4 and a sound wave acquisition structure; the sound wave acquisition structure is an "H"-shaped flat structure composed of two element diaphragms 1 and a coupling diaphragm 2; in the flat structure, the parts of the two element diaphragms 1 on the same side of the coupling diaphragm 2 are the signal acquisition ends, and the parts of the two element diaphragms 1 on the other side of the coupling diaphragm 2 are the fixed ends. The support structure 4 is a flat plate with a rectangular through hole in the middle. The sound wave acquisition structure is embedded in the rectangular through hole and is in the same plane as the support structure 4. The fixed end of the sound wave acquisition unit 13 is fixedly connected to the inner side wall of the rectangular through hole; the base 10 is a barrel-shaped structure with two through holes 9 at the bottom. The support structure 4 is fixed on the opening side of the barrel-shaped structure. The space enclosed by the base 10 and the support structure 4 is the signal acquisition cavity.

[0006] Furthermore, the support structure 4, the element diaphragm 1, and the coupling diaphragm 2 in the acoustic wave acquisition unit 13 are all made of 304 stainless steel material.

[0007] Furthermore, the acoustic wave acquisition unit 13 has a thickness of 5 to 30 micrometers; the acoustic wave acquisition unit 13 has a thickness of 5 to 30 micrometers; the two element diaphragms 1 are rectangular flat plates with the same shape. The length of the long side of the rectangular flat plate is 3 to 4 millimeters, and the length of the short side is 0.5 to 1.5 millimeters. The center distance between the two element diaphragms 1 is 1 to 1.5 millimeters; the side length A of the side of the coupling diaphragm 2 in contact with the long side of the element diaphragm is 1 to 1.5 millimeters, and the distance B from the center point of the coupling diaphragm 2 to the inner side wall of the rectangular through hole inside the support structure 4 is 0.6 to 2 millimeters. The inner side wall is the inner side wall for fixing the acoustic wave acquisition unit 13.

[0008] Furthermore, the integrated structure composed of the support structure 4, the element diaphragm 1, and the coupling diaphragm 2 is made by cutting a sheet with a laser marking machine.

[0009] A bionic binary array acoustic orientation sensor based on the hearing of the housefly Omnia caesar has the following characteristics: the sensor includes a bionic binary array acoustic orientation acquisition unit and an optical fiber F-P measurement system; the optical fiber F-P measurement system includes two single-mode optical fibers 7. The two single-mode optical fibers 7 respectively pass through two through holes at the bottom of the base 10 and extend into the signal acquisition cavity. The optical fiber end faces of the two single-mode optical fibers 7 located in the signal acquisition cavity respectively correspond to the two element diaphragms 1 at the signal acquisition end in the acoustic wave acquisition structure to form an F-P resonant cavity.

[0010] Furthermore, the sensor further includes: multiple glass capillary tubes 8; multiple glass capillary tubes 8 are embedded in the gap between each single-mode optical fiber 7 and the embedded through hole 9 to fix the single-mode optical fiber 7 and prevent it from shaking or moving in the through hole 9. Each glass capillary tube 8 is adhesively fixed to the embedded through hole 9.

[0011] Furthermore, the two element diaphragms 1 respectively face one single-mode optical fiber 7. The distance between the end face of the single-mode optical fiber 7 and the element diaphragm 1 is 0.1 to 1.0 millimeter, and the laser beam in the single-mode optical fiber 7 is a single-wavelength beam.

[0012] Further, the fiber optic F-P measurement system further includes two single-mode optical fibers 7. The two single-mode optical fibers 7 respectively pass through two through holes at the bottom of the base 10 and extend into the signal acquisition cavity. The two single-mode optical fibers 7 in each through hole are opposite to an element diaphragm 1. The laser beam wavelengths of the two single-mode optical fibers 7 opposite to each element diaphragm 1 are the same. The distance from the end faces of the two single-mode optical fibers 7 to the element diaphragm 1 is between 0.1 mm and 1.0 mm, and the distances from the end faces of the two single-mode optical fibers 7 to the element diaphragm 1 are different.

[0013] Further, the end face of the single-mode optical fiber 7 and the element diaphragm have a laser beam wavelength of 1525 nm to 1575 nm.

[0014] A parasitic organism called Ormia ochracea in North America, although its body size is very small, can accurately orient to the calls of its host crickets. Through experiments and dissections, it is found that thanks to the keratin coupling between its two eardrum membranes, it can amplify the time delay of the sound waves received by the two ears, equivalent to obtaining a virtual array with a larger aperture under the original physical size of the array. Thanks to this, Ormia ochracea can achieve precise orientation of the sound source azimuth with an extremely small ear spacing far less than the sound wave wavelength. The present invention is based on the ear structure of this organism and designs a sensor based on the coupled vibration of two degrees of freedom.

[0015] The beneficial effects of the present invention are as follows:

[0016] For the acquisition unit of the present invention: 1. Using a rectangular diaphragm fixed at one end as an element can effectively and sensitively convert the sound waves in space into the vibration of the free end of the diaphragm, thereby sensitively sensing the acoustic mechanical wave signals at different positions in space; 2. The acquisition unit can be processed by laser marking machine using a whole piece of 304 stainless steel to produce the above structure. Its processing is simple, the cost is low, the structure is firm, the performance is reliable, it is not sensitive to temperature changes, and it has good corrosion resistance.

[0017] For the sensor of the present invention: 1. The acquisition unit is a structure in which two element diaphragms are connected by a coupling film. The sensor introduces the auditory coupling amplification mechanism of Ormia ochracea to amplify the tiny time delay between the two element signals, thereby improving the azimuth sensitivity of the directional transmitter and realizing high-resolution measurement of the azimuth angle of the sound signal source under extremely small size conditions; 2. Using the fiber optic F-P interferometer measurement method to detect vibration signals has the excellent characteristics of simple equipment, firm and reliable, anti-electromagnetic interference, corrosion resistance, and low cost; 3. Adopting the direction finding mechanism of spatial array time delay can use a large number of existing array signal processing methods.

[0018] The present invention is applicable to the fields of acoustic orientation function and bionic acoustic orientation array sensor technology in miniaturized intelligent information platforms such as unmanned aerial vehicles, unmanned boats, and intelligent robots. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the three-dimensional structure of a bionic binary array sound direction-finding and acquisition unit based on the hearing of Ormia ochracea as described in Embodiment 1.

[0020] Figure 2 For Figure 1 Schematic diagram of the bottom structure of the bionic binary array sound direction-finding and acquisition unit shown.

[0021] Figure 3 Schematic diagram of the structure of the sound wave acquisition unit in the sound wave acquisition unit.

[0022] Figure 4 Cross-sectional view of a bionic binary array sound direction-finding sensor based on the hearing of Ormia ochracea as described in Embodiment 2.

[0023] Figure 5 For Figure 1 Schematic diagram of the separation of the sound wave acquisition unit from the base in.

[0024] Wherein, 1 is an array element diaphragm, 2 is a coupling diaphragm, 4 is a support structure, 7 is a single-mode optical fiber, 8 is a glass capillary, 9 is a through hole, 10 is a base, 12 is an air interference cavity between the optical fiber end face and the mirror, and 13 is a sound wave acquisition unit. SPECIFIC EMBODIMENTS

[0025] Embodiment 1. This embodiment will be described in conjunction with FIGS. Figure 1 、 2 、3 and 5. This embodiment provides a bionic binary array sound direction-finding and acquisition unit based on the hearing of Ormia ochracea. The acquisition unit includes: a sound wave acquisition unit 13 and a base 10. The sound wave acquisition unit 13 includes a support structure 4 and a sound wave acquisition structure. The sound wave acquisition structure is an "H"-shaped flat structure composed of two array element diaphragms 1 and a coupling diaphragm 2. In the flat structure, the parts of the two array element diaphragms 1 on the same side of the coupling diaphragm 2 are signal acquisition ends, and the parts of the two array element diaphragms 1 on the other side of the coupling diaphragm 2 are fixed ends. The support structure 4 is a flat plate with a rectangular through hole in the middle. The sound wave acquisition structure is embedded in the rectangular through hole and is in the same plane as the support structure 4. The fixed end of the sound wave acquisition unit 13 is fixedly connected to the inner side wall of the rectangular through hole. The base 10 is a barrel-shaped structure with two through holes 9 at the bottom. The support structure 4 is fixed on the open side of the barrel-shaped structure. The space enclosed by the base 10 and the support structure 4 is a signal acquisition cavity.

[0026] In this embodiment, the acoustic wave acquisition structure in the acoustic wave acquisition unit 13 is implemented by two rectangular diaphragms fixed at one end, so as to effectively and sensitively convert the acoustic waves in space into the vibration of the free end of the diaphragm, thereby sensitively sensing the acoustic-mechanical wave signals at different positions in space. The base 10 is used to support the acoustic wave acquisition unit 13. At the same time, the space enclosed by the base 10 and the support structure 4 can be used to place the signal source directional processing system for detecting the vibration of the acoustic wave acquisition structure, realizing the function of converting the vibration signal into an optical signal.

[0027] Embodiment 2. With reference to the attached Figure 3 This embodiment will be described. This embodiment is a further limitation on a bionic binary array acoustic orientation acquisition unit based on the hearing of Omnia caesar. The support structure 4, the array element diaphragm 1, and the coupling diaphragm 2 in the acoustic wave acquisition unit 13 are all made of 304 stainless steel.

[0028] In this embodiment, the acoustic wave acquisition unit made of stainless steel has the advantages of low cost, insensitivity to temperature changes, and good corrosion resistance.

[0029] Embodiment 3. With reference to the attached Figure 3 This embodiment will be described. This embodiment is a further limitation on a bionic binary array acoustic orientation acquisition unit based on the hearing of Omnia caesar. The acoustic wave acquisition unit 13 has a thickness of 5 to 30 micrometers; the acoustic wave acquisition unit 13 has a thickness of 5 to 30 micrometers; the two array element diaphragms 1 are rectangular flat plates with the same shape. The length of the long side of the rectangular flat plate is 3 to 4 millimeters, and the length of the short side is 0.5 to 1.5 millimeters. The center distance between the two array element diaphragms 1 is 1 to 1.5 millimeters; the side length A of the side of the coupling diaphragm 2 in contact with the long side of the array element diaphragm is 1 to 1.5 millimeters, and the distance B from the center point of the coupling diaphragm 2 to the inner side wall of the rectangular through hole inside the support structure 4 is 0.6 to 2 millimeters. The inner side wall is the inner side wall for fixing the acoustic wave acquisition unit 13.

[0030] In this embodiment, the modal frequencies of the two array element diaphragms can be set between 100 Hz and 5000 Hz, so as to obtain good acoustic wave response sensitivity, a large phase difference amplification factor between array elements, and a small phase difference amplification non-linearity. Its vibration deflection can reach several nanometers to dozens of nanometers, which is convenient for the optoelectronic detection system to detect it.

[0031] Embodiment 4. With reference to the attached Figure 3To describe this embodiment, this embodiment further defines a bionic binary array sound direction acquisition unit based on the hearing of Omia ochracea provided in Embodiment 1. The integrated structure composed of the support structure 4, the array element diaphragm 1, and the coupling diaphragm 2 is made by cutting a plate with a laser marking machine.

[0032] In this embodiment, the above structure is cut and processed from a whole piece of 304 stainless steel by a laser marking machine, which adds the advantages of simple processing, strong structure, and reliable performance.

[0033] Embodiment Five, in combination with the attached Figure 4 To describe this embodiment, this embodiment is a bionic binary array sound direction sensor of a bionic binary array sound direction acquisition unit based on the hearing of Omia ochracea provided in any one of Embodiments 1 to 4. The sensor includes a bionic binary array sound direction acquisition unit and an optical fiber F-P measurement system; the optical fiber F-P measurement system includes two single-mode optical fibers 7. The two single-mode optical fibers 7 respectively pass through two through holes at the bottom of the base 10 and extend into the signal acquisition cavity. The optical fiber end faces of the two single-mode optical fibers 7 located in the signal acquisition cavity respectively correspond to two array element diaphragms 1 at the signal acquisition end in the acoustic wave acquisition structure to form an F-P resonant cavity.

[0034] In this embodiment, the optical fiber F-P measurement system uses the measurement method of an optical fiber F-P interferometer to realize the function of detecting the vibration signals of the two array element diaphragms 1 at the signal acquisition end, and has excellent characteristics of simple structure, firmness and reliability, anti-electromagnetic interference, corrosion resistance, and low cost. Among them, the F-P cavity is the simplest optical cavity, and its advantage is to make full use of the working substance, so that the light beam oscillates within the entire working substance, and can be used for high-power output pulsed lasers.

[0035] Embodiment Six, in combination with the attached Figure 2 To describe this embodiment, this embodiment further defines a bionic binary array sound direction sensor of a bionic binary array sound direction acquisition unit based on the hearing of Omia ochracea provided in Embodiment Five. The sensor further includes: multiple glass capillary tubes 8; multiple glass capillary tubes 8 are embedded in the gap between each single-mode optical fiber 7 and the embedded through hole 9 to fix the single-mode optical fiber 7 and prevent it from shaking or moving in the through hole 9. Each glass capillary tube 8 is adhesively fixed to the embedded through hole 9.

[0036] In this embodiment, placing the optical fiber in the glass capillary tube plays a better fixing role, and is also convenient for the production of the sensor and the replacement of the optical fiber.

[0037] Embodiment Seven, in combination with the attached Figure 1This embodiment further defines a bionic binary array sound direction sensor based on the hearing of Omnia caesar, provided in Embodiment 5. The two array element diaphragms 1 are respectively facing a single-mode optical fiber 7. The distance between the end face of the single-mode optical fiber 7 and the array element diaphragm 1 is 0.1 mm to 1.0 mm, and the laser beam in the single-mode optical fiber 7 is a single-wavelength beam.

[0038] In this embodiment, the single-wavelength and single-cavity-length intensity demodulation method is used to demodulate the optical signal, which has the advantages of high sensitivity, simple equipment, and mature scheme; a better interference fringe contrast can be obtained when the distance between the end face and the mirror is between 0.1 mm and 1 mm, which can improve the detection sensitivity and obtain a larger signal-to-noise ratio.

[0039] Embodiment 8, in combination with the attached Figure 1 This embodiment further defines a bionic binary array sound direction sensor based on the hearing of Omnia caesar, provided in Embodiment 5. The fiber optic F-P measurement system further includes two single-mode optical fibers 7. The two single-mode optical fibers 7 respectively pass through two through holes at the bottom of the base 10 and extend into the signal acquisition cavity. The two single-mode optical fibers 7 in each through hole are facing an array element diaphragm 1. The laser beam wavelengths in the two single-mode optical fibers 7 facing each array element diaphragm 1 are the same. The distances from the end faces of the two single-mode optical fibers 7 to the array element diaphragm 1 are between 0.1 mm and 1.0 mm, and the distances from the end faces of the two single-mode optical fibers 7 to the array element diaphragm 1 are different.

[0040] In this embodiment, there are two single-mode optical fibers in each through hole on the base. The double-cavity-length DC compensation, quadrature phase shift and other methods are used to demodulate the optical signal, which has the advantages of high sensitivity and the sensitivity and range are not restricted by the quadrature operating point.

[0041] Embodiment 9, in combination with the attached Figure 1 This embodiment further defines a bionic binary array sound direction sensor based on the hearing of Omnia caesar, provided in Embodiment 5. The laser wavelength is 1525 nm to 1575 nm.

[0042] In this embodiment, when the laser wavelength is set at about 1500 nm, its loss during fiber transmission is the lowest and the propagation distance is the farthest.

[0043] The above-mentioned multiple embodiments only give the specific structures for implementing a bionic binary array sound direction and sensor based on the hearing of Omnia caesar of the present invention, and do not limit the protection scope of this application.

Claims

1. A bionic binary array sound direction and acquisition unit based on the hearing of Ormia ochracea, characterized in that: The acquisition unit includes: a sound wave acquisition unit (13) and a base (10). The sound wave acquisition unit (13) includes a support structure (4) and a sound wave acquisition structure. The sound wave acquisition structure is an "H"-shaped flat structure composed of two element diaphragms (1) and a coupling diaphragm (2). In the flat structure, the part of the two element diaphragms (1) on the same side of the coupling diaphragm (2) is the signal acquisition end, and the part of the two element diaphragms (1) on the other side of the coupling diaphragm (2) is the fixed end. The support structure (4) is a flat plate with a rectangular through hole in the middle. The sound wave acquisition structure is embedded in the rectangular through hole and is in the same plane as the support structure (4). The fixed end of the sound wave acquisition unit (13) is fixedly connected to the inner side wall of the rectangular through hole. The base (10) is a barrel-shaped structure with two through holes (9) at the bottom. The support structure (4) is fixed on the opening side of the barrel-shaped structure. The space enclosed by the base (10) and the support structure (4) is the signal acquisition cavity.

2. A bionic binary array sound direction and acquisition unit based on the hearing of Ormia ochracea according to claim 1, characterized in that: The support structure (4), the element diaphragm (1) and the coupling diaphragm (2) in the sound wave acquisition unit (13) are all made of 304 stainless steel material.

3. A bionic binary array sound direction and acquisition unit based on the hearing of Ormia ochracea according to claim 1, characterized in that: The thickness of the sound wave acquisition unit (13) is 5 to 30 microns. The two element diaphragms (1) are rectangular flat plates with the same shape. The length of the long side of the rectangular flat plate is 3 to 4 millimeters, and the length of the short side is 0.5 to 1.5 millimeters. The center distance between the two element diaphragms (1) is 1 to 1.5 millimeters. The side length A of the side of the coupling diaphragm (2) in contact with the long side of the element diaphragm is 1 to 1.5 millimeters. The distance B from the center point of the coupling diaphragm (2) to the inner side wall of the rectangular through hole inside the support structure (4) is 0.6 to 2 millimeters. The inner side wall is the inner side wall for fixing the sound wave acquisition unit (13).

4. A bionic binary array sound direction and acquisition unit based on the hearing of Ormia ochracea according to claim 1, characterized in that: The integrated structure composed of the support structure (4), the element diaphragm (1) and the coupling diaphragm (2) is made by cutting a plate with a laser marking machine.

5. A bionic binary array sound direction sensor based on the hearing of Ormia ochracea using the acquisition unit according to any one of claims 1-4, characterized in that: The sensor described above includes a bionic binary array acoustic direction-finding and acquisition unit and an optical fiber F-P measurement system; the optical fiber F-P measurement system includes two single-mode optical fibers (7), and the two single-mode optical fibers (7) respectively pass through two through holes at the bottom of the base (10) and extend into the signal acquisition cavity. The optical fiber end faces of the two single-mode optical fibers (7) located in the signal acquisition cavity respectively correspond to two element diaphragms (1) at the signal acquisition end in the acoustic wave acquisition structure to form an F-P resonant cavity.

6. A bionic binary array acoustic direction-finding sensor based on the hearing of Ormia ochracea according to claim 5, wherein: The sensor further includes: multiple glass capillary tubes (8); multiple glass capillary tubes (8) are embedded in the gap between each single-mode optical fiber (7) and the embedded through hole (9) for fixing the single-mode optical fiber (7) to prevent it from shaking or moving in the through hole (9), and each glass capillary tube (8) is adhesively fixed to the embedded through hole (9).

7. A bionic binary array acoustic direction-finding sensor based on the hearing of Ormia ochracea according to claim 5, wherein: The two element diaphragms (1) respectively face one single-mode optical fiber (7). The distance between the end face of the single-mode optical fiber (7) and the element diaphragm (1) is 0.1 mm to 1.0 mm, and the laser beam in the single-mode optical fiber (7) is a single-wavelength beam.

8. A bionic binary array acoustic direction-finding sensor based on the hearing of Ormia ochracea according to claim 5, wherein: The optical fiber F-P measurement system further includes two single-mode optical fibers (7), and the two single-mode optical fibers (7) respectively pass through two through holes at the bottom of the base (10) and extend into the signal acquisition cavity. The two single-mode optical fibers (7) in each through hole face one element diaphragm (1). The laser beam wavelengths of the two single-mode optical fibers (7) facing each element diaphragm (1) are the same. The distance from the end faces of the two single-mode optical fibers (7) to the element diaphragm (1) is between 0.1 mm and 1.0 mm, and the distances from the end faces of the two single-mode optical fibers (7) to the element diaphragm (1) are different.

9. A bionic binary array acoustic direction-finding sensor based on the hearing of Ormia ochracea according to claim 7 or 8, wherein: The wavelength of the laser beam of the end face of the single-mode optical fiber (7) and the element diaphragm is 1525 nm to 1575 nm.

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