Piezoelectric ceramic transducer array element, underwater acoustic transducer array structure and method

Abstract

The invention relates to a piezoelectric ceramic transducer array element, an underwater acoustic transducer array structure and an underwater vehicle positioning method. The underwater acoustic transducer array structure comprises a plurality of annular arrays formed by arranging a plurality of piezoelectric ceramic transducer array elements with annular surface radiation heads, and further comprises a plurality of fan-shaped arrays formed by arranging a plurality of piezoelectric ceramic transducer array elements with fan-shaped surface radiation heads. The circular array has the advantages that the array element radiation heads of the circular array form a circular structure and have the best appearance matching degree with the circular section of the guidance head of the underwater vehicle, the receiving and transmitting radiation area of the array is large, the sound wave transmitting intensity is high, and the receiving sensitivity is high. Compared with a rectangular array or array, the circular array is concentrated in acoustic energy density and high in emission directivity. Array elements or an array forming the array are in central symmetry about the central axis of the array, and the orientation of a target can be more easily distinguished by detecting the intensity difference of reflection echoes of the symmetrical array or the time difference between the reflection echoes of the symmetrical array and the transmitted sound waves.

Description

Technical Field

[0001] The present invention belongs to the technical field of underwater acoustic transducers, and in particular relates to an underwater acoustic transducer array structure and method for underwater vehicles. Background Art

[0002] Underwater acoustic transducers are devices that realize the conversion of acoustic and electrical energy. As transducers develop towards high power, controlled directivity, high bandwidth and precise target perception, a single transducer can no longer meet the comprehensive requirements, and a transducer array must be used to achieve the purpose of accurately locating and detecting targets. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a piezoelectric ceramic transducer array element, an underwater acoustic transducer array structure of the piezoelectric ceramic transducer array element, and an underwater vehicle positioning method based on the underwater acoustic transducer array structure;

[0004] A piezoelectric ceramic transducer array element, wherein the center frequency and the frequency band width of the transducer array element are consistent; the transducer array element comprises: a screw, a bolt, a piezoelectric ceramic and a radiation head, and the radiation head is provided with a fixing groove; the radiation head comprises a sector-shaped radiation head and an annular radiation head, and the radiation head area and the external structure of each transducer array element are different, and the transducer length and structure can be adjusted to ensure that the sector-shaped radiation head as a whole is a part of a truncated cone body, and the annular radiation head as a whole is a part of a torus body;

[0005] The screw rod passes through the bolt to fix the piezoelectric ceramic in the fixing groove of the radiation head; the screw rod is used to provide stress and press the annular piezoelectric ceramic 3 onto the radiation head through the bolt; the bolt is used to provide pre-tightening force.

[0006] An underwater acoustic transducer array structure using piezoelectric ceramic transducer array elements:

[0007] It includes a plurality of annular arrays composed of a plurality of piezoelectric ceramic transducer array elements with annular surface radiation heads, and also includes a plurality of fan-shaped arrays composed of a plurality of piezoelectric ceramic transducer array elements with fan-shaped surface radiation heads; the circular surface of the hydroacoustic transducer array structure is well matched with the circular cross-section of the head of the underwater vehicle, which can increase the transmitting and receiving area of ​​the transducer array and improve the transmitting response and receiving sensitivity of the transducer array;

[0008] A plurality of fan-shaped arrays are located at the center of the underwater acoustic transducer array structure, and the radiation heads of the plurality of fan-shaped arrays form a circular structure; outside the circular structure are a plurality of annular arrays nested in the direction of the extension line of the radius of the circular structure, and from inside to outside, the inner annular array can be nested in the outer annular array;

[0009] Taking the central axis of the hydroacoustic transducer array structure as a reference, multiple annular arrays are arranged in a centrally symmetrical manner, and multiple fan-shaped arrays are also arranged in a centrally symmetrical manner; taking the central axis of the hydroacoustic transducer array structure as a reference, an array of the same type that is symmetrical to each annular array or each fan-shaped array can be found.

[0010] Preferably, the center of the underwater acoustic transducer array structure includes four fan-shaped arrays (four piezoelectric ceramic transducer element arrays A1, A2, A3 and A4 with fan-shaped surface radiation heads), and the underwater acoustic transducer array structure includes three annular arrays from the inside to the outside (from the inside to the outside, eight piezoelectric ceramic transducer element arrays B1 to B8 with annular surface radiation heads, twelve piezoelectric ceramic transducer element arrays C1 to C12 with annular surface radiation heads, and sixteen piezoelectric ceramic transducer element arrays D1 to D16 with annular surface radiation heads).

[0011] A method for positioning an underwater vehicle based on an underwater acoustic transducer array structure, the method comprising the following steps:

[0012] According to the requirements of the strength of the acoustic wave signal, all or part of the fan-shaped array, all or part of the annular array, or a combination of all or part of the fan-shaped array and all or part of the annular array are used as the acoustic wave transmitting array (which can be composed of an underwater acoustic transducer array with an annular, fan-shaped or circular transmitting and receiving surface); the acoustic wave transmitting array transmits acoustic waves;

[0013] The sound waves are reflected by the target;

[0014] All of the fan-shaped array and all of the annular array jointly receive the acoustic wave echo signal reflected by the target; when receiving the acoustic wave echo signal: the direction of the target is determined according to the intensity difference or time difference of the echo signal received by one pair of annular arrays or fan-shaped arrays in symmetrical positions; the running speed of the target is detected according to the frequency difference between the emitted acoustic wave signal and the received acoustic wave signal;

[0015] When the intensities of the echo signals received by the two centrally symmetrical arrays are the same, or the time difference of the echo signals is zero, it is determined that the target is directly in front of the underwater acoustic transducer array structure;

[0016] When there is a certain difference in the intensity of the echo signals received by the two centrally symmetrical arrays, or a certain difference in the time difference between the echo signals and the transmitted sound wave signals, the direction of the target is calculated according to the difference; the running speed of the target is calculated according to the difference between the frequency of the transmitted sound wave and the frequency of the echo signal;

[0017] Repeat the above steps many times to obtain the accurate position and specific running speed of the target.

[0018] The beneficial effects of the present invention are:

[0019] The present invention adopts piezoelectric ceramic transducer array elements, which have high transduction efficiency, high sensitivity and good consistency; the underwater acoustic transducer array structure designed by the present invention concentrates the sound waves in a certain specified direction as much as possible when transmitting sound waves, and minimizes the transmitted sound waves in other directions, which can improve the energy density in the specified direction and the directivity of the array; the underwater acoustic transducer array structure designed by the present invention can ensure a certain frequency bandwidth when receiving target reflected sound waves, and can also ensure a flat receiving response within the frequency bandwidth, and has a high receiving sensitivity to reflected echoes, and can accurately detect the sound wave frequency difference caused by the target movement, and then detect the target's direction and movement direction.

[0020] The annular or circular transducer array elements composed of the piezoelectric ceramic transducer array elements of the present invention are all symmetrically arranged along the central axis of the array. Compared with the rectangular array or array, the transmitted sound wave intensity is large, the sound wave energy density is concentrated, and the transmission directivity is high. The hydroacoustic transducer array structure designed by the present invention is circular as a whole, and this shape has a high degree of matching with the circular cross-section of the underwater vehicle, which can increase the area of ​​the array receiving transmission / receiving surface of the hydroacoustic transducer and improve the overall array result transmission response sensitivity and receiving sensitivity of the hydroacoustic transducer.

[0021] The method of the present invention adopts a polar coordinate system to determine the target orientation. Compared with a rectangular coordinate system, the target orientation detection and control method of the present invention is simpler. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic diagram of a transducer array element with a radiation head being a fan-shaped surface;

[0023] Figure 2 It is a schematic diagram of a transducer array element whose radiation head is a ring surface;

[0024] Figure 3 It is a schematic diagram of the structure of the transducer array composed of fan-shaped and ring-shaped radiation head array elements;

[0025] Figure 4 An example diagram of a transducer array structure composed of fan-shaped and ring-shaped radiating head array elements;

[0026] Figure 5 This is a schematic diagram of acoustic wave transmission and reception when the target is located directly in front of the array structure;

[0027] Figure 6 Schematic diagram of acoustic wave transmission and reception when the target deviates from the front of the array structure.

[0028] Explanation of the reference numerals: screw rod 1 , bolt 2 , annular piezoelectric ceramic 3 , sector-shaped radiation head 4 , annular radiation head 5 , annular array 6 , sector-shaped array 7 . DETAILED DESCRIPTION

[0029] The present invention is further described below in conjunction with embodiments. The description of the following embodiments is only used to help understand the present invention. It should be noted that for ordinary persons in the art, without departing from the principle of the present invention, the present invention can also be modified in some ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0030] Example 1

[0031] A piezoelectric ceramic transducer array element, such as Figure 1 As shown, the central frequency and bandwidth of the transducer array element are consistent; the transducer array element comprises: a screw 1, a bolt 2, an annular piezoelectric ceramic 3 and a sector-shaped surface radiation head 4, and a fixing groove is provided on the sector-shaped surface radiation head 4. The radiation head area and the external structure of each transducer array element are different. By adjusting the length and structure of the transducer, it can be ensured that the sector-shaped surface radiation head 4 is a part of the truncated cone as a whole;

[0032] The screw rod 1 is used to provide stress, and the annular piezoelectric ceramic 3 is pressed onto the sector-shaped radiation head 4 through the bolt 2; the bolt is used to provide a pre-tightening force.

[0033] Example 2

[0034] A piezoelectric ceramic transducer array element, such as Figure 2 As shown, the center frequency and bandwidth of the transducer array element are consistent; the transducer array element comprises: a screw 1, a bolt 2, an annular piezoelectric ceramic 3 and an annular surface radiation head 5, and a fixing groove is provided on the annular surface radiation head 5; the radiation head area and the external structure of each transducer array element are different, and the length and structure of the transducer can be adjusted to ensure that the annular surface radiation head 5 is a part of the circular ring body as a whole;

[0035] The screw rod 1 passes through the bolt 2 to fix the annular piezoelectric ceramic 3 in the fixing groove of the annular surface radiation head 5; the screw rod 1 is used to provide stress, and the annular piezoelectric ceramic 3 is pressed onto the annular surface radiation head 5 through the bolt 2, and a thread is provided on the inner wall of the annular piezoelectric ceramic 3; the bolt is used to provide pre-tightening force.

[0036] Example 3

[0037] On the basis of Example 1 and Example 2, Figure 3 and Figure 4 As shown, this embodiment includes an underwater acoustic transducer array structure using piezoelectric ceramic transducer array elements, including a plurality of annular arrays 6 composed of a plurality of piezoelectric ceramic transducer array elements with annular surface radiation heads 5, and also includes a plurality of fan-shaped arrays 7 composed of a plurality of piezoelectric ceramic transducer array elements with fan-shaped surface radiation heads 4; the circular surface of the underwater acoustic transducer array structure is well matched with the circular cross-section of the head of the underwater vehicle, which can increase the transmitting and receiving area of ​​the transducer array and improve the transmitting response and receiving sensitivity of the transducer array;

[0038] Four fan-shaped arrays 7 (four piezoelectric ceramic transducer array element arrays A1, A2, A3 and A4 with fan-shaped radiation heads 4) are located at the center of the underwater acoustic transducer array structure, forming a circular structure in the center; outside the circular structure are three annular arrays 6 nested in the direction of the extension line of the circular structure radius (from the inside to the outside, they are eight piezoelectric ceramic transducer array element arrays B1 to B8 with annular radiation heads 5, twelve piezoelectric ceramic transducer array element arrays C1 to C12 with annular radiation heads 5, and sixteen piezoelectric ceramic transducer array element arrays D1 to D16 with annular radiation heads 5), from the inside to the outside, the inner annular array 6 can be nested in the outer annular array 6;

[0039] Taking the central axis of the hydroacoustic transducer array structure as a reference, multiple annular arrays 6 are arranged in a centrally symmetrical manner, and multiple fan-shaped arrays 7 are also arranged in a centrally symmetrical manner; taking the central axis of the hydroacoustic transducer array structure as a reference, an array of the same type that is symmetrical to each annular array 6 or each fan-shaped array 7 can be found.

[0040] Example 4

[0041] On the basis of Embodiments 1 to 3, this embodiment includes a method for positioning an underwater vehicle based on an underwater acoustic transducer array structure, based on a polar coordinate system (compared with a rectangular coordinate system, the polar coordinate system makes the positioning method simpler), and the method includes the following steps:

[0042] According to the requirements of the strength of the acoustic wave signal, an array A composed of four fan-shaped arrays 7 (four piezoelectric ceramic transducer array element arrays A1, A2, A3 and A4 with fan-shaped radiation heads 4) is used as an acoustic wave transmitting array (which can be composed of an underwater acoustic transducer base array with a transmitting and receiving surface of a ring, fan or circle); the acoustic wave transmitting array transmits acoustic waves;

[0043] The sound waves are reflected by the target;

[0044] The whole of the fan array 7 (four piezoelectric ceramic transducer array element arrays A1, A2, A3 and A4 with fan-shaped radiation heads 4) and the whole of the annular array 6 (from the inside to the outside, eight piezoelectric ceramic transducer array element arrays B1 to B8 with annular radiation heads 5, twelve piezoelectric ceramic transducer array element arrays C1 to C12 with annular radiation heads 5, and sixteen piezoelectric ceramic transducer array element arrays D1 to D16 with annular radiation heads 5) are used to jointly receive the acoustic wave echo signal reflected by the target. When receiving the acoustic wave echo signal: according to a pair of centrally symmetrical annular arrays in the outermost ring 6 (i.e., the annular array pair composed of D1 to D4 and D9 to D12) to determine the direction of the target; according to the frequency difference between the emitted sound wave signal and the echo signal received by a pair of centrally symmetrical annular arrays 6 (i.e., the annular array pair composed of D1 to D4 and D9 to D12) in the outermost ring, the running speed of the target is detected; because the distance of the centrally symmetrical annular array in the outermost ring is the largest on the base array surface, the intensity difference, time difference and frequency difference of the detected reflected echo are the largest, and the sensitivity of perceiving the direction and movement speed of the target is higher;

[0045] like Figure 5 As shown, when the intensities of the echo signals received by the two centrally symmetrical arrays are the same, or the time difference of the echo signals is zero, it is determined that the target is located directly in front of the underwater acoustic transducer array structure;

[0046] like Figure 6 As shown, when there is a certain difference in the intensity of the echo signals received by the two centrally symmetrical arrays, or a certain difference in the time difference between the echo signals and the transmitted sound wave signals, the direction of the target is calculated according to the difference; the running speed of the target is calculated according to the difference between the frequency of the transmitted sound wave and the frequency of the echo signal;

[0047] Repeat the above steps many times to obtain the accurate position and specific running speed of the target.

Claims

1. A piezoelectric ceramic transducer array element, the transducer array element comprising: A screw rod (1), a bolt (2), an annular piezoelectric ceramic (3) and a radiation head, wherein the radiation head is provided with a fixing groove; the screw rod (1) passes through the bolt (2) to fix the annular piezoelectric ceramic (3) in the fixing groove of the radiation head; the annular piezoelectric ceramic (3) is pressed against the radiation head by the screw rod (1); the characteristic is that the radiation head comprises a sector-shaped radiation head (4) and an annular radiation head (5), the sector-shaped radiation head (4) as a whole is a part of a cut piece of a truncated cone body, and the annular radiation head (5) as a whole is a part of a cut piece of a torus body.

2. An underwater acoustic transducer array structure using the piezoelectric ceramic transducer array element of claim 1, characterized in that: It comprises a plurality of annular arrays (6) composed of a plurality of piezoelectric ceramic transducer array elements with annular surface radiation heads (5), and also comprises a plurality of fan-shaped arrays (7) composed of a plurality of piezoelectric ceramic transducer array elements with fan-shaped surface radiation heads (4); A plurality of fan-shaped arrays (7) are located at the center of the underwater acoustic transducer array structure, and the radiation heads of the plurality of fan-shaped arrays (7) form a circular structure; outside the circular structure are a plurality of annular arrays (6) that are mutually nested in the direction of the extension line of the radius of the circular structure, and from the inside to the outside, the annular array (6) on the inner side can be nested in the annular array (6) on the outer side; Taking the central axis of the hydroacoustic transducer array structure as a reference, the plurality of annular arrays (6) are arranged in a centrally symmetrical manner, and the plurality of fan-shaped arrays (7) are also arranged in a centrally symmetrical manner; taking the central axis of the hydroacoustic transducer array structure as a reference, an array of the same type that is symmetrical to each annular array (6) or each fan-shaped array (7) can be found.

3. The underwater acoustic transducer array structure according to claim 2, characterized in that: The underwater acoustic transducer array structure includes four fan-shaped arrays (7) at its center, and the underwater acoustic transducer array structure includes three annular arrays (6) from the inside to the outside.

4. A method for positioning an underwater vehicle based on the underwater acoustic transducer array structure as claimed in claim 3, characterized in that: The method comprises the following steps: According to the requirements of the strength of the acoustic wave signal, all or part of the fan-shaped array (7), all or part of the annular array (6), or a combination of all or part of the fan-shaped array (7) and all or part of the annular array (6) are used as the acoustic wave emission array; the acoustic wave emission array emits acoustic waves; The sound waves are reflected by the target; All of the fan-shaped arrays (7) and all of the annular arrays (6) jointly receive the acoustic wave echo signal reflected by the target; when receiving the acoustic wave echo signal: the direction of the target is determined based on the intensity difference or time difference of the echo signals received by one pair of annular arrays (6) or fan-shaped arrays (7) in symmetrical positions; and the running speed of the target is detected based on the frequency difference between the emitted acoustic wave signal and the received acoustic wave signal; When the intensities of the echo signals received by the two centrally symmetrical arrays are the same, or the time difference of the echo signals is zero, it is determined that the target is directly in front of the underwater acoustic transducer array structure; When there is a certain difference in the intensity of the echo signals received by the two centrally symmetrical arrays, or a certain difference in the time difference between the echo signals and the transmitted sound wave signals, the direction of the target is calculated according to the difference; the running speed of the target is calculated according to the difference between the frequency of the transmitted sound wave and the frequency of the echo signal; Repeat the above steps many times to obtain the accurate position and specific running speed of the target.

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