Underwater acoustic sensor

Abstract

The present invention provides an underwater acoustic sensor. The underwater acoustic sensor comprises at least one transducer. When the underwater acoustic sensor operates, a piezoelectric material layer in the transducer generates acoustic waves, the generated acoustic waves are emitted from a first surface of the transducer, and some of the acoustic waves leak from one side of a first side wall. A first sound absorption structure is at least arranged in one transducer to surround the first side wall of the transducer, and the first sound absorption structure absorbs the acoustic waves leaked from the one side of the first side wall of the transducer, thereby eliminating the interference of lateral acoustic wave leakage. When two or more transducers are used, the first sound absorption structure may also eliminate the interference of acoustic waves leaked from the transducer emitting the acoustic waves and residual vibration on the transducer receiving the acoustic waves, thereby reducing the blind area of the sensor, and further improving the sensitivity of the sensor.

Description

An underwater acoustic sensor

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on November 22, 2023, with application number 2023115681508 and invention name “A Water Acoustic Sensor”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of acoustic wave sensors, and more particularly to an underwater acoustic sensor. Background Art

[0003] During operation, underwater robots need to use underwater acoustic ranging sensors to detect the surrounding environment, determine whether there are obstacles and the depth of the water, and decide the next operation route.

[0004] Sensors commonly used in robot obstacle avoidance include laser sensors, infrared sensors, and ultrasonic sensors. However, due to the unique working environment of underwater robots, light attenuates very quickly in water. Therefore, laser and infrared sensors have a short range in water and are ineffective. Sound waves, on the other hand, attenuate slowly in water and travel long distances, so underwater distance measurement and obstacle avoidance are generally performed using sound waves.

[0005] Underwater acoustic sensors utilize the propagation and reflection characteristics of sound waves in water. They can measure distance through electroacoustic conversion and information processing, thereby measuring the distance to underwater targets. During the measurement process, the underwater acoustic sensor first transmits a sound wave signal for a period of time. When encountering a target object, the sound wave signal will be reflected back and received by the sensor. By measuring the time difference between transmission and reception, the distance to the target object can be calculated. This distance is the product of the time difference between the underwater acoustic sensor receiving and transmitting the sound wave and 1 / 2 of the sound speed of the sound wave in water.

[0006] When using an underwater acoustic sensor to measure the distance to a target object, there are two problems: the first problem is that when a transducer with an integrated transmitter and receiver is used in the underwater acoustic sensor, the underwater acoustic sensor will have a large measurement blind area due to the influence of residual vibration, and the sound waves from the side of the underwater acoustic sensor will leak, causing lateral sound wave interference, which will also increase the blind area and reduce the measurement sensitivity; the second problem is that when a transducer with a separate transmitter and receiver is used in the underwater acoustic sensor, the sound wave leakage from the side of the transmitting transducer will directly interfere with the receiving transducer, thereby increasing the measurement blind area and further reducing the sensitivity of the underwater acoustic sensor.

[0007] Therefore, reducing the measurement blind area of ​​the underwater acoustic sensor and increasing the sensitivity of the underwater acoustic sensor has become an urgent problem to be solved. Summary of the Invention

[0008] In view of this, in order to solve the above problems, the present invention provides an underwater acoustic sensor, the technical solution is as follows:

[0009] An underwater acoustic sensor, comprising:

[0010] at least one transducer;

[0011] The transducer includes a first surface, a second surface disposed opposite to the first surface in a first direction; and a first sidewall located between the first surface and the second surface; a piezoelectric material layer is disposed on a side of the first surface facing the second surface; the first direction is perpendicular to the first surface;

[0012] A first sound absorbing structure; in at least one of the transducers, the first sound absorbing structure surrounds the first side wall.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] The present invention provides an underwater acoustic sensor, which includes at least one transducer, the transducer including a first surface, a second surface arranged opposite to the first surface in a first direction; and a first side wall located between the first surface and the second surface; a piezoelectric material layer is provided on the side of the first surface facing the second surface; the first direction is perpendicular to the first surface; when the underwater acoustic sensor is working, the piezoelectric material layer in the transducer generates sound waves, the generated sound waves are emitted from the first surface of the transducer, and part of the sound waves leak from one side of the first side wall; in at least one transducer, a first sound absorbing structure is provided surrounding the first side wall of the transducer, the first sound absorbing structure absorbs the sound waves leaked from the transducer from one side of the first side wall, thereby reducing the blind area of ​​the sensor and further improving the sensitivity of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0016] FIG1 is a schematic structural diagram of an existing sensor;

[0017] FIG2 is a schematic diagram of the structure of the sensor measuring the target object in FIG1;

[0018] FIG3 is a schematic diagram of the residual vibration and echo signal of an existing sensor;

[0019] FIG4 is a schematic diagram of the structure of another existing sensor for measuring a target object;

[0020] FIG5 is a schematic diagram of the structure of another existing sensor;

[0021] FIG6 is a schematic cross-sectional view of a partial structure of an underwater acoustic sensor provided by an embodiment of the present invention.

[0022] FIG7 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0023] FIG8 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0024] FIG9 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0025] FIG10 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0026] FIG11 is a cross-sectional schematic diagram of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0027] FIG12 is a schematic diagram of the front structure of an underwater acoustic sensor provided by an embodiment of the present invention;

[0028] FIG13 is a schematic diagram of the front structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0029] FIG14 is a cross-sectional schematic diagram of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0030] FIG15 is a schematic diagram of the front structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0031] FIG16 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0032] FIG17 is a cross-sectional schematic diagram of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0033] FIG18 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0034] FIG19 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0035] FIG20 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0036] FIG21 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention;

[0037] FIG22 is a cross-sectional schematic diagram of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] Based on the content in the background technology, refer to Figure 1, which is a structural diagram of an existing sensor; it includes a measuring circuit Q and a first transducer 01, wherein the first transducer 01 is a transducer that transmits and receives in one; refer to Figure 2, which is a structural diagram of the sensor in Figure 1 measuring a target object; the first transducer 01 in the sensor is provided with a piezoelectric ceramic 02 on one side, which is the direction of emission of the main lobe of the sensor, that is, the measurement direction of the sensor. There is a target B1 in this measurement direction. After the first measurement sound wave signal A1 is emitted, the first transducer 01 will receive The sensor calculates the distance between the target object B1 and the sensor through the time difference between the first echo signal A2 and the first measurement sound wave signal A1. However, at the same time, a first lateral sound wave signal A3 leaks from the side of the first transducer 01. When there is an obstacle B2 in the direction of propagation of the first lateral sound wave signal A3, the first transducer 01 will also receive the second echo signal A4 reflected from the obstacle B2. When the echo signal reflected from the obstacle B2 is strong enough, an erroneous measurement result will occur.

[0040] After the first transducer 01 transmits the first measuring sound wave signal A1, the sound wave does not stop immediately, but goes through a decay process, during which residual vibrations will be generated; refer to Figure 3, which is a schematic diagram of the residual vibrations and echo signals of an existing sensor; segment T1 is the measuring sound wave signal, segment T2 is the residual vibration signal, and segment T3 is the echo signal. Measurement can only be performed when the echo signal is significantly stronger than the residual vibration signal. Measurement cannot be performed during the period of waiting for the residual vibration to decay. The distance corresponding to this period is called a blind spot. In the transceiver-in-one transducer shown in Figure 1, there will be a blind spot due to the influence of the residual vibration; in order to reduce the blind spot, the usual way is to increase the frequency of the transducer. Generally, the higher the frequency, the smaller the blind spot; but the higher the frequency, the faster the sound wave signal will decay during transmission, which will cause the measuring range to become smaller.

[0041] In addition, refer to Figure 4, which is a structural diagram of another existing sensor for measuring a target object; the sensor is provided with a second transducer 03 and a third transducer 04, the second transducer 03 is used to transmit sound wave signals, and the third transducer 04 is used to receive sound wave signals, that is, the transducer in the sensor can be a transducer with a separate transmitter and receiver, and the side of the second transducer 03 provided with a piezoelectric ceramic 05 is the direction of emission of the sensor's main lobe, that is, the measurement direction of the sensor, and there is a target object B3 in this measurement direction. After the second transducer 03 transmits the second measurement sound wave signal A5, the third transducer 04 will receive the third echo signal A6 reflected back by the target object B3, and the sensor receives the third echo signal A6 through the third echo signal The distance between the target object B3 and the sensor is calculated by the time difference between the second lateral acoustic wave signal A6 and the second measurement acoustic wave signal A5; however, there will also be a leaked second lateral acoustic wave signal A7 on the side of the second transducer 03, and this leaked second lateral acoustic wave signal A7 can be received by the third transducer 04. In order to make the measurement result accurate, the second transducer 03 generally waits for a period of time after the transmission is completed, and the echo signal is not detected until the leaked second lateral acoustic wave signal A7 is relatively weak or basically disappears. The distance value corresponding to this waiting time is the blind spot. In order to avoid the influence of the blind spot caused by the second lateral acoustic wave signal A7, the threshold for detecting the third echo signal A6 can be increased, but this will lead to a decrease in the sensitivity of the measurement.

[0042] In addition, since each transducer has a certain detection angle, when the sensor is required to cover a larger angle, a multi-beam (multi-transducer) solution will be used. Refer to Figure 5, which is a structural diagram of another existing sensor; the sensor includes a measurement circuit 06 and multiple fourth transducers 07. When the multi-beam solution is adopted, it is similar to the transceiver split solution. When the transmitting transducer transmits a signal, the main sound wave is emitted in the direction of the main lobe of the sensor, but a small number of sound waves are emitted from the side. These sound wave signals will be received by other surrounding receiving transducers. Although the measurement angle of this solution becomes larger, the blind spot and sensitivity performance are still poor.

[0043] Based on this, the present invention provides an underwater acoustic sensor, which includes at least one transducer, the transducer including a first surface, a second surface arranged opposite to the first surface in a first direction; and a first sidewall located between the first surface and the second surface; a piezoelectric material layer is arranged on the side of the first surface facing the second surface; the first direction is perpendicular to the first surface; when the underwater acoustic sensor is working, the piezoelectric material layer in the transducer generates sound waves, which are emitted from the first surface of the transducer, and some of the sound waves leak from one side of the first sidewall. In at least one transducer, a first sound absorbing structure is arranged around the first sidewall of the transducer, and the first sound absorbing structure absorbs the sound waves leaked from one side of the first sidewall of the transducer, thereby reducing the blind area of ​​the sensor and further improving the sensitivity of the sensor. In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] 6 , which is a schematic cross-sectional view of a partial structure of an underwater acoustic sensor provided by an embodiment of the present invention, the underwater acoustic sensor includes:

[0045] At least one transducer 11 .

[0046] The transducer 11 includes a first surface 12, a second surface 13 arranged opposite to the first surface 12 in a first direction D; and a first side wall 14 located between the first surface 12 and the second surface 13; a piezoelectric material layer 15 is arranged on the side of the first surface 12 facing the second surface 13; the first direction D is perpendicular to the first surface 12.

[0047] A first sound absorbing structure 16 ; at least in one of the transducers 11 , the first sound absorbing structure 16 surrounds the first side wall 14 .

[0048] Specifically, the transducer 11 can be a transceiver that is used to both transmit and receive sound waves; the transducer 11 can also be a transmitting transducer that is only used to transmit sound waves; the transducer 11 can also be a receiving transducer that is only used to receive sound waves; no specific limitation is made here, and it can be set as needed.

[0049] As shown in Figure 6, taking the cross-sectional structure of a transducer 11 as an example, a piezoelectric material layer 15 is provided on the side of the first surface 12 of the transducer 11 facing the second surface 13, that is, the piezoelectric material layer 15 is located inside the transducer 11 and is close to the first surface 12. The piezoelectric material layer 15 can be a piezoelectric ceramic, etc. The side of the first surface 12 facing away from the second surface 13 is the forward direction of sound wave emission, the side of the first surface 12 facing the second surface 13 is the rear direction of sound wave emission, and one side of the first side wall 14 is the lateral direction of sound wave emission.

[0050] When the transducer 11 generates sound waves, the sound waves will be emitted from the side of the first surface 12 of the transducer 11 away from the second surface 13, that is, from the side where the piezoelectric material layer 15 is provided. When the sound waves encounter a target object, an echo will be generated. The transducer 11 receives the echo to further detect the distance of the target object. In this process, part of the sound waves will leak from the side of the underwater acoustic sensor.

[0051] As shown in FIG6 , the transducer 11 may be cylindrical or in other shapes, and is not specifically limited thereto. In this embodiment, the cylindrical transducer 11 is taken as an example for illustration. The first surface 12 of the transducer 11 is the upper bottom surface of the cylinder, the second surface 13 is the lower bottom surface of the cylinder, the first side wall 14 is the side surface of the cylinder, and the first sound absorbing structure 16 surrounds the first side wall 14 and may be the outer side of the first side wall 14 as shown in FIG6 , that is, the outer wall surrounding the side surface of the cylinder.

[0052] Referring to Figure 7, Figure 7 is a cross-sectional schematic diagram of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention; wherein, the piezoelectric material layer 15 is in close contact with the side of the first surface 12 facing the second surface 13, and the positive and negative electrodes of the piezoelectric material layer 15 are connected to the cable; a damping sound-absorbing layer 151 is further provided on one side of the first surface 12, and a shielding material layer 152 is further provided on the side of the damping sound-absorbing layer 151 facing away from the first surface 12. The damping sound-absorbing layer 151 can reduce part of the residual vibration and absorb part of the sound wave signal emitted by the piezoelectric material layer 15 toward the second surface 13. The shielding material layer 152 is generally a layer of metal foil, such as copper foil, for shielding electromagnetic interference; the first sound-absorbing structure 16 can also be a layer surrounding the first side as shown in Figure 7 The inner side of the wall 14, that is, the inner wall surrounding the side of the cylinder; refer to Figure 8, Figure 8 is a cross-sectional schematic diagram of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention; the first sound absorbing structure 16 can also be surrounded by a certain distance from the first side wall 14 as shown in Figure 8, and the other positions are filled with potting glue. When the sound wave leaks, the first sound absorbing structure 16 will absorb the sound wave leaked from the underwater acoustic sensor to the first side wall 14. In at least one transducer 11, a first sound absorbing structure 16 is arranged to surround the first side wall 14 of the transducer 11. The first sound absorbing structure 16 will absorb the sound wave leaked from the transducer 11 to the first side wall 14, thereby reducing the blind area of ​​the sensor and further improving the sensitivity of the sensor.

[0053] Optionally, in another embodiment of the present invention, the underwater acoustic sensor further includes:

[0054] The second sound absorbing structure 17 is located on a side of the second surface 13 away from the first surface 12 ; or the second sound absorbing structure 17 is located on a side of the second surface 13 facing the first surface 12 .

[0055] The orthographic projection of the second sound absorbing structure 17 in the first direction D at least covers a portion of the second surface 13 .

[0056] Specifically, in the transducer 11 provided with the first sound absorbing structure 16, the second sound absorbing structure 17 is provided on the side of the second surface 13 away from the first surface 12, and the orthographic projection of the second sound absorbing structure 17 in the first direction D covers at least a portion of the second surface 13. As shown in FIG6, the second sound absorbing structure 17 is located on the outside of the second surface 13, covering the edge area of ​​the second surface 13, that is, covering the edge area of ​​the outer wall of the lower bottom surface of the cylinder; or the second sound absorbing structure 17 is provided on the side of the second surface 13 facing the first surface 12. As shown in FIG7, although the side of the piezoelectric material layer 15 facing the second surface 13 has a damping sound absorbing layer 151, there will still be weak sound wave leakage. In order to better absorb the leaked sound waves, the second sound absorbing structure 17 is provided on the inside of the second surface 13, covering at least a portion of the second surface 13. In FIG7, the second sound absorbing structure 17 completely covers the second surface 13, that is, completely covers the inner wall of the lower bottom surface of the cylinder; refer to FIG9, FIG9 is provided in an embodiment of the present invention. A schematic cross-sectional view of a partial structure of another underwater acoustic sensor; the second sound absorbing structure 17 can also be designed at any position between the piezoelectric material layer 15 of the transducer 11 and the second surface 13. The orthographic projection of the second sound absorbing structure 17 in the first direction D covers at least a portion of the second surface 13. As shown in FIG9 , the orthographic projection of the second sound absorbing structure 17 in the first direction D can be slightly smaller than the orthographic projection of the piezoelectric material layer 15 in the first direction D. Alternatively, the second sound absorbing structure 17 can be designed with a mesh structure or a strip structure. This allows the potting compound, the piezoelectric material layer 15, and the first sidewall 14 to be integrated into a single unit, thereby strengthening the structure. It should be noted that the potting compound has a slight internal depression after curing, so there may be a partial depression on one side of the second surface 13. Of course, it is also possible that the first surface 12 is parallel to the second surface 13, but this does not affect the function of the second sound absorbing structure 17. When sound waves leak from the side of the first surface 12 facing the second surface 13, that is, leaking backward, the second sound absorbing structure 17 absorbs the backward leaking sound waves.

[0057] The first sound absorbing structure 16 absorbs sound waves leaked from the transducer 11 on one side of the first side wall 14, and the second sound absorbing structure 17 absorbs sound waves leaked from the side of the first surface 12 of the transducer 11 facing the second surface 13, thereby suppressing lateral and rearward interference of the transducer 11, thereby significantly reducing the blind area of ​​the sensor and improving the sensitivity of the sensor.

[0058] Optionally, referring to Figure 10, Figure 10 is a cross-sectional schematic diagram of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention; in another embodiment of the present invention, the first sound absorbing structure 16 includes a first side X and a second side Y opposite to each other in the first direction D.

[0059] The second side Y is adjacent to the first surface 12 , and a distance d is provided between the second side Y and the first surface 12 , wherein 0 mm≦d<2 mm.

[0060] Specifically, the first side X of the first sound absorbing structure 16 is close to the second surface 13, and the second side Y is close to the first surface 12. There may be an error distance between the second side Y and the first surface 12. The error distance can be d, where 0mm≤d<2mm, including endpoint values, for example, it can be 0mm or 1mm or 1.5mm. It should be noted that d is an absolute value, so the second side Y can be in the direction from the first surface 12 to the second surface 13, as shown in Figure 10, with a distance d from the first surface 12; it can also be in the direction from the second surface 13 to the first surface 13. In the direction of the first surface 12, the distance d from the first surface 12 is slightly beyond the first surface 12, for example, by 0.5 mm or 1 mm. To achieve the best effect, the second side Y is preferably flush with the first surface 12. In other words, the smaller d is, the better the effect of the first sound absorbing structure 16 is. For example, when multiple transducers 11 are provided with the first sound absorbing structure 16 and the second sound absorbing structure 17, at least one of the transducers 11 can achieve a better effect by having the second side Y of the first sound absorbing structure 16 flush or nearly flush with the first surface 12 of the transducer 11.

[0061] Optionally, in another embodiment of the present invention, the first side X is disposed adjacent to the second surface 13 , and the first side X exceeds the second surface 13 in the first direction D.

[0062] Specifically, since the transducers 11 include at least two, when the two transducers 11 are adjacent and relatively close, the first side X of the first sound absorbing structure 16 can be arranged to exceed the second surface 13 in the first direction D. In this case, the two adjacent transducers 11 are better protected by the first side wall 14 and will not affect each other, thereby improving the sound absorption effect.

[0063] Optionally, in another embodiment of the present invention, the material of the first sound absorbing structure 16 is a foam material.

[0064] Optionally, in another embodiment of the present invention, the material of the second sound absorbing structure 17 is a foam material.

[0065] Specifically, the material of the first sound absorbing structure 16 and the second sound absorbing structure 17 is a foam material, including but not limited to foam, foam glue, or sponge. For example, in actual use, considering the underwater working environment and weather resistance requirements, the material of the first sound absorbing structure 16 and the second sound absorbing structure 17 can use ethylene propylene diene monomer foam (EPDM foam). It should be noted that the material of the first sound absorbing structure 16 and the second sound absorbing structure 17 only needs to have strong sound absorption ability. For example, it can also be a foam material with bubbles or pores inside.

[0066] Optionally, in another embodiment of the present invention, referring to FIG11 , FIG11 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention; referring to FIG12 , FIG12 is a schematic front view of the structure of an underwater acoustic sensor provided by an embodiment of the present invention; the underwater acoustic sensor further includes:

[0067] The housing 18 has the transducer 11 installed inside.

[0068] The housing 18 includes: a bottom surface 19 and a top surface 20 arranged opposite to each other in the first direction D; a second side wall 21 located between the bottom surface 19 and the top surface 20; the top surface 20 has a first opening area L, and / or the second side wall has a second opening area; wherein the opening area exposes the first surface 12 of the transducer 11.

[0069] Specifically, there is no specific limitation on the shape of the shell 18, and it can be a cylinder or a rectangular parallelepiped, etc. The shell 18 has a bottom surface 19 and a top surface 20 that are relatively arranged in the first direction D. For example, when the shell 18 is a cylinder, the bottom surface 19 is the lower bottom surface of the cylinder, the top surface 20 is the upper bottom surface of the cylinder, and the second side wall 21 is the side surface of the cylinder; when the shell 18 is a rectangular parallelepiped, the two relatively arranged surfaces of the rectangular parallelepiped are the bottom surface 19 and the top surface 20, and the other surfaces are the second side wall 21.

[0070] Among them, the top surface 20 of the shell 18 has a first opening area L, or the second side wall 21 has a second opening area, or, the top surface 20 has the first opening area L and the second side wall 21 also has a second opening area. Figures 11 and 12 only show the first opening area L designed on the top surface 20. Both the first opening area L and the second opening area are for exposing the first surface 12 of the transducer 11. If there is no opening area, the sound waves generated by the first surface 12 of the transducer 11 will be blocked by the shell 18, reducing the accuracy of the measurement. The shell 18 is used to install the transducer 11 and can fix the transducer 11 well. Optionally, in another embodiment of the present invention, the shell 18 is one, and a transducer 11 is installed inside the shell 18; the transducer 11 is a transceiver-transmitter.

[0071] Specifically, when a shell 18 is provided and a transducer 11 is provided in the shell 18, a first opening area L can be designed on the top surface 20, or a second opening area can be designed on the second side wall. It is only necessary to expose the first surface 12. As shown in Figures 11 and 12, the first opening area L completely exposes the first surface 12 of the transducer 11. At this time, the second side wall 21 can completely wrap the transducer 11, thereby increasing the stability of the transducer.

[0072] When there is only one housing 18 and one transducer 11, the transducer 11 is a transceiver integrated with a transmitter. In the transceiver integrated with a transmitter, the first sound absorbing structure 16 surrounds the second side wall 21, and the orthographic projection of the second sound absorbing structure 17 in the first direction D covers at least a portion of the second surface 13, for example, covering the edge of the second surface 13. Of course, it can also completely cover the second surface 13, and the design can be based on actual needs.

[0073] After the transceiver transmits sound waves, the first sound-absorbing structure 16 absorbs the sound waves leaked from the first side wall 14 of the transceiver, and the second sound-absorbing structure 17 absorbs the sound waves leaked from the side of the first surface 12 of the transceiver facing the second surface 13, thereby suppressing lateral and rearward interference of the transceiver and improving the sensitivity of the sensor.

[0074] Optionally, in another embodiment of the present invention, referring to Figure 13, Figure 13 is a schematic diagram of the front structure of another underwater acoustic sensor provided in an embodiment of the present invention; the number of the shell 18 is one, the top surface 20 has the first opening area L, and when the second side wall 21 does not have the second opening area, the number of the first opening areas L is M, M≥2, and M is a positive integer, and each first opening area L corresponds to the installation of one transducer 11.

[0075] Specifically, when the first opening area L is set on the top surface 20, the number of the first opening areas L can be M, for example, M can be 2, 3, 4, etc., each first opening area L is arranged at intervals, and each first opening area L is correspondingly installed with a transducer 11. For the stability of the installation, an isolation component can be set between adjacent first opening areas L to form each first opening area L into an independent accommodating area, and the transducer 11 installed in the accommodating area is more stable.

[0076] Refer to Figure 14, which is a cross-sectional schematic diagram of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention; refer to Figure 15, which is a front structural schematic diagram of another underwater acoustic sensor provided by an embodiment of the present invention; for explanation, when M is 2, when there are two first opening areas L, an isolation component K is provided between the two first opening areas L. At this time, although the shape of the outer shell 18 is a rectangular parallelepiped, due to the existence of the isolation component K, the stability is still good.

[0077] Optionally, in another embodiment of the present invention, some of the transducers 11 are transmitting transducers, and some of the transducers 11 are receiving transducers.

[0078] Two transducers 11 are installed correspondingly in the two first opening areas L, where one transducer 11 may be a transmitting transducer and the other transducer 11 may be a receiving transducer.

[0079] In this case, a first sound absorbing structure 16 and a second sound absorbing structure 17 can be provided on both the transmitting transducer and the receiving transducer. As shown in FIG14 , the first sound absorbing structure 16 of the transmitting transducer surrounds the first side wall 14 of the transmitting transducer, and the second sound absorbing structure 17 covers at least a portion of the second surface 13. In the receiving transducer, the first sound absorbing structure 16 surrounds the first side wall 14 of the receiving transducer, and the second sound absorbing structure 17 covers at least a portion of the second surface 13. In this case, the sound absorbing structure has a better effect and serves as redundancy. Even if the sound absorbing structure on one transducer 11 is damaged, the overall effect is not affected.

[0080] It should be noted that two transducers 11 are installed corresponding to the two first opening areas L, and both can be integrated transceiver transducers, in which one transducer 11 is used to transmit sound waves and the other transducer 11 is used to receive sound waves; some can also be integrated transceiver transducers, and the others can include transmitting transducers or receiving transducers, and there is no specific limitation.

[0081] Alternatively, referring to FIG16, FIG16 is a cross-sectional schematic diagram of a partial structure of another underwater acoustic sensor provided by an embodiment of the present invention; the first sound absorbing structure 16 and the second sound absorbing structure 17 may also be provided on only one of the transducers 11. Since there are only two transducers 11, and the transmission and reception are provided separately, the first sound absorbing structure 16 and the second sound absorbing structure 17 are provided only in one transducer 11, that is, the other transducer 11 can be ensured not to be interfered with by the lateral sound waves and the residual vibration. For example, when one transducer 11 When the first transducer 11 is a transmitting transducer and the other transducer 11 is a receiving transducer, a first sound absorbing structure 16 and a second sound absorbing structure 17 are provided on the transmitting transducer. The lateral and rearward leakage signals generated by the residual vibration of the transmitting transducer are absorbed by the first sound absorbing structure 16 and the second sound absorbing structure 17. The signal received by the receiving transducer is mainly the forward echo, thereby reducing the impact on the receiving transducer, thereby greatly reducing or even eliminating the blind spot. Of course, the first sound absorbing structure 16 and the second sound absorbing structure 17 can also be provided on the receiving transducer.

[0082] The first sound-absorbing structure 16 absorbs sound waves leaked from the transmitting transducer on one side of the first side wall 14, and the second sound-absorbing structure 17 absorbs sound waves leaked from the side of the first surface 12 of the transmitting transducer facing the second surface 13, thereby suppressing lateral and rearward interference of the transmitting transducer. At the same time, the residual vibration generated by the transmitting transducer will not interfere with the receiving transducer, thereby greatly reducing the blind spot of the sensor and improving the sensitivity of the sensor.

[0083] Optionally, refer to Figure 17, which is a cross-sectional schematic diagram of a partial structure of another underwater acoustic sensor provided in an embodiment of the present invention; in another embodiment of the present invention, the number of the shell 18 is one, the top surface does not have the first opening area, and the second side wall 21 has the second opening area O, the number of the second opening areas O is M, M≥2, and M is a positive integer, and each second opening area O corresponds to the installation of one transducer 11.

[0084] Specifically, when the second side wall 21 is provided with a second opening area O, the second side wall 21 can be an entire side surface. For example, when the housing 18 is a cylinder, the second side wall 21 is the side surface of the cylinder. The second opening areas O can be M, for example, M can be 2, 3, 4, etc., and each second opening area O is correspondingly installed with a transducer 11, and each second opening area O is arranged at intervals.

[0085] When one of the transducers 11 is used to transmit sound waves, the other one or more transducers are used to receive sound waves; generally, the transducer 11 adjacent to the transducer 11 that transmits sound waves is used as the transducer that receives sound waves, wherein the transducer 11 that transmits sound waves can be a transmitting transducer, and the transducer 11 that receives sound waves can be a receiving transducer; or, the transducer 11 that transmits sound waves and the transducer 11 that receives sound waves can both be integrated transceivers, one of which is used to transmit sound waves, and the other one or more are used to receive sound waves.

[0086] Since each transducer 11 has a limited detection angle, to increase the detection angle, the transmitting and receiving transducers 11 are alternately replaced, enabling the measurement to cover a wider angle, up to 360 degrees. A first sound-absorbing structure 16 surrounds the first sidewall 14 of each transducer 11, and a second sound-absorbing structure 17 is provided to cover at least a portion of the second surface 13. The first and second sound-absorbing structures 16, 17 absorb acoustic signals leaking laterally and backward, eliminating lateral interference. Since the transmitting and receiving transducers are separately provided, blind spots can be significantly reduced or even eliminated, significantly improving the signal-to-noise ratio and thus sensitivity. Alternatively, at least one of the transmitting and receiving transducers 11 used in each measurement is provided with the first and second sound-absorbing structures 16, 17. That is, either the transmitting or receiving transducer 11 is provided with a sound-absorbing structure.

[0087] It should be noted that when the top surface 20 has a first opening area and the second side wall 21 also has a second opening area, the measuring range of the underwater acoustic sensor will be larger.

[0088] Optionally, refer to Figure 18, which is a cross-sectional schematic diagram of the partial structure of another underwater acoustic sensor provided in an embodiment of the present invention; in another embodiment of the present invention, the number of the shells 18 is N, N≥2, and N is a positive integer; each of the shells 18 is respectively installed with a transducer 11.

[0089] Specifically, in this embodiment, each transducer 11 is provided with a housing 18, and the number of housings 18 may be N, for example, N may be 2, 3, 4, etc., correspondingly there are N transducers 11. In this case, the transmitting and receiving functions of the N transducers 11 are separately provided. When one of the transducers 11 serves as a transmitting transducer, the other one or more transducers serve as receiving transducers. A first sound absorbing structure 16 surrounds the first side wall 14 of each transducer 11, and a second sound absorbing structure 17 is provided to cover at least a portion of the second surface 13. The first sound absorbing structure 16 and the second sound absorbing structure 17 absorb the sound wave signals leaked laterally and backwards, eliminating lateral and backward interference. Since the transmitting transducer and the receiving transducer are provided separately, the blind spot can be greatly reduced or even eliminated, and the signal-to-noise ratio is greatly improved, thereby improving the sensitivity.

[0090] Optionally, referring to FIG19 , FIG19 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided in an embodiment of the present invention; referring to FIG20 , FIG20 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided in an embodiment of the present invention; referring to FIG21 , FIG21 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided in an embodiment of the present invention; referring to FIG22 , FIG22 is a schematic cross-sectional view of a partial structure of another underwater acoustic sensor provided in an embodiment of the present invention; in another embodiment of the present invention, the underwater acoustic sensor further includes:

[0091] A circuit board 23 is electrically connected to the transducer 11 and is used to control the working state of the transducer 11 .

[0092] The circuit board 23 is located inside the housing 18 , or the circuit board 23 is located outside the housing 18 .

[0093] Specifically, the circuit board 23 has an acoustic wave transmitting circuit and an echo detection circuit, which can process communication protocols and calculate measurement results, and is used to control the working state of the transducer 11. The circuit board 23 and the transducer 11 are connected by a wire. Generally, a flexible wire is best, which can weaken the conduction of the acoustic wave signal through the wire and the circuit board 23.

[0094] When the circuit board 23 is located inside the shell 18, the circuit board 23 can be located on the side of the second surface 13 away from the first surface 12, as shown in Figures 19 and 20, and there is no specific limitation on the position of the circuit board 23; when the circuit board 23 is located outside the shell 18, there is no specific limitation on the position of the circuit board 23, as shown in Figures 21 and 22, Figure 19 is Figure 14 with the circuit board 23 added, Figure 20 is Figure 17 with the circuit board 23 added, Figure 21 is Figure 16 with the circuit board 23 added, and Figure 22 is Figure 18 with the circuit board 23 added.

[0095] Optionally, as shown in FIG19 , FIG20 , and FIG21 , in another embodiment of the present invention, the underwater acoustic sensor further includes:

[0096] A cable 24 is connected to the circuit board 23 ; the cable 24 is used to establish a communication connection between an external device and the circuit board 23 , and to transmit the electrical energy output by the external device to the circuit board 23 .

[0097] Specifically, the external device can provide power and collect data, and the cable 24 connects the external device and the circuit board 23, can transmit the power output by the external device to the circuit board 23, and can transmit the echo signal detected by the circuit board 23 to the external device.

[0098] Optionally, in another embodiment of the present invention, the underwater acoustic sensor further includes:

[0099] The third sound absorbing structure 25 is located on a side of the second surface 13 away from the first surface 12 .

[0100] The orthographic projection of the third sound absorbing structure 25 in the first direction D at least covers a portion of the second surface 13 .

[0101] Specifically, when the second surface 13 is not completely covered, a third sound absorbing structure 25 may be provided, and the orthographic projection of the third sound absorbing structure 25 in the first direction D at least partially covers the second surface 13 , thereby further reducing interference caused by sound wave leakage on one side of the second surface 13 .

[0102] As shown in FIG19 , when the circuit board 23 is disposed inside the housing 18, the circuit board 23 can be parallel to the second surface 13. In this case, the third sound absorbing structure 25 is disposed between the circuit board 23 and the second surface 13. For example, the third sound absorbing structure 25 is disposed on the side of the circuit board 23 facing the second surface 13. The orthographic projection of the third sound absorbing structure 25 in the first direction D at least partially covers the second surface 13, thereby absorbing sound waves leaking from the second surface 13. As shown in FIG21 , when the circuit board 23 is disposed outside the housing 18, the third sound absorbing structure 25 can be disposed on the side of the bottom surface 19 facing the second surface 13. The orthographic projection of the third sound absorbing structure 25 in the first direction D at least partially covers the second surface 13, thereby absorbing sound waves leaking from the second surface 13.

[0103] Optionally, in another embodiment of the present invention, the third sound absorbing structure 25 is made of foam material.

[0104] Specifically, the material of the third sound absorbing structure 25 can be a foam material, including but not limited to foam, foam glue, or sponge. For example, in actual use, considering the underwater working environment and weather resistance requirements, the material of the third sound absorbing structure 25 can use ethylene propylene diene monomer foam (EPDM foam). It should be noted that the material of the third sound absorbing structure 25 only needs to have strong sound absorption ability. For example, it can also be a foam material with bubbles or pores inside.

[0105] Optionally, as shown in FIG19 , FIG20 , FIG21 , and FIG22 , in another embodiment of the present invention, the underwater acoustic sensor further includes:

[0106] The potting compound 26 is used to fill the cavity inside the housing 18 .

[0107] Specifically, after the transducer 11 is installed in the housing 18, the housing 18 may have a cavity position. The cavity position inside the housing 18 is filled with potting glue 26, and the potting glue 26 fixes the transducer 11. Or when the circuit board 23 is located inside the housing 18, the circuit board 23 and the transducer 11 are fixed together, so that the overall structure of the underwater acoustic sensor can be stable and reliable. In order to make the transducer 11 fixed more firmly, the second sound absorbing structure 17 can only cover part of the second surface 13. For example, the second sound absorbing structure 17 is made into a circular ring, a circular ring with small mesh holes, or a plurality of strips; in this way, the potting glue 26 can contact the second surface 13 of the transducer 22, and firmly bond the transducer 11, the circuit board 23 and the housing 18 together to ensure long-term reliability in an underwater environment.

[0108] The above is a detailed introduction to an underwater acoustic transducer provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

[0109] It should be noted that each embodiment in this specification focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referenced to each other.

[0110] It should also be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that the process, method, article, or apparatus comprising a series of elements inherent to the elements, or also including elements inherent to these processes, methods, articles, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.

[0111] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A hydroacoustic sensor, characterized in that: The hydroacoustic sensor comprises: at least one transducer; The transducer comprises a first surface, a second surface arranged opposite to the first surface in a first direction; and a first side wall located between the first surface and the second surface; a piezoelectric material layer is arranged on a side of the first surface facing the second surface; the first direction is perpendicular to the first surface; A first sound absorbing structure; at least in one of the transducers, the first sound absorbing structure surrounds the first side wall.

2. The hydroacoustic sensor according to claim 1, characterized in that: The first sound absorbing structure comprises a first side and a second side opposite to each other in the first direction; The second side is disposed adjacent to the first surface, and a distance d is provided between the second side and the first surface, wherein 0 mm ≤ d < 2 mm.

3. The hydroacoustic sensor according to claim 2, characterized in that: The first side is disposed adjacent to the second surface, and the first side exceeds the second surface in the first direction.

4. The hydroacoustic sensor according to claim 1, characterized in that: The hydroacoustic sensor also includes: a second sound absorbing structure, wherein the second sound absorbing structure is located on a side of the second surface away from the first surface; or the second sound absorbing structure is located on a side of the second surface facing the first surface; An orthographic projection of the second sound absorbing structure in the first direction at least covers a portion of the second surface.

5. The hydroacoustic sensor according to claim 1, characterized in that: The hydroacoustic sensor also includes: a third sound absorbing structure located on a side of the second surface away from the first surface; The orthographic projection of the third sound absorbing structure in the first direction at least covers a portion of the second surface.

6. The hydroacoustic sensor according to claim 1, characterized in that: The hydroacoustic sensor also includes: A housing, wherein the transducer is installed inside the housing; The housing comprises: a bottom surface and a top surface arranged opposite to each other in the first direction; a second side wall located between the bottom surface and the top surface; the top surface has a first opening area, and / or the second side wall has a second opening area; wherein the opening area exposes the first surface of the transducer.

7. The hydroacoustic sensor according to claim 6, characterized in that: The number of the shells is N, N≥2, and N is a positive integer; one transducer is installed inside each of the shells.

8. The hydroacoustic sensor according to claim 6, characterized in that: When the number of the shells is one, the top surface has the first opening area, and the second side wall does not have the second opening area, the number of the first opening areas is M, M≥2, and M is a positive integer, and one transducer is installed corresponding to each first opening area.

9. The hydroacoustic sensor according to claim 6, characterized in that: The number of the shells is one, the top surface does not have the first opening area, and when the second side wall has the second opening area, the number of the second opening areas is M, M≥2, and M is a positive integer, and one transducer is installed corresponding to each second opening area.

10. The hydroacoustic sensor according to claim 7, 8 or 9, characterized in that: Some of the transducers are transmitting transducers, and some of the transducers are receiving transducers.

11. The hydroacoustic sensor according to claim 6, characterized in that: There is one shell, and one transducer is installed inside the shell; the transducer is a transceiver integrated transducer.

12. The hydroacoustic sensor according to claim 6, characterized in that: The hydroacoustic sensor also includes: A circuit board, the circuit board is electrically connected to the transducer, and the circuit board is used to control the working state of the transducer; The circuit board is located inside the housing, or the circuit board is located outside the housing.

13. The hydroacoustic sensor according to claim 12, characterized in that: The hydroacoustic sensor also includes: A cable is connected to the circuit board; the cable is used to establish a communication connection between an external device and the circuit board, and to transmit the electrical energy output by the external device to the circuit board.

14. The hydroacoustic sensor according to claim 1, characterized in that: The material of the first sound absorbing structure is a foaming material.

15. The hydroacoustic sensor according to claim 4, characterized in that: The material of the second sound absorbing structure is foamed material.

16. The hydroacoustic sensor according to claim 5, characterized in that: The material of the third sound absorbing structure is foamed material.

17. The hydroacoustic sensor according to claim 6, characterized in that: The hydroacoustic sensor also includes: A potting compound is used to fill the cavity inside the shell.

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