Weak scatterer acoustic target strength measurement apparatus and method

Abstract

The application discloses a weak scattering body acoustic target intensity measuring device and method. The acoustic target intensity measuring device comprises a mounting base, a rotating ring (3) and a transducer (8). The rotating ring is rotatably mounted on the mounting base and is driven to rotate by a driving device. A wire suspension rotating mechanism is arranged on the rotating ring. The wire suspension rotating mechanism is provided with a fine wire and a mechanism for driving the fine wire to rotate. The fine wire of the wire suspension rotating mechanism passes through the center of the rotating ring. The transducer is arranged based on a displacement mechanism. The detection direction of the transducer is towards the center of the rotating ring. Under the driving action of the displacement mechanism, the transducer can be close to or away from the center of the rotating ring. The acoustic target intensity measuring method of the application is based on the acoustic target intensity measuring device. The acoustic target intensity of a weak scattering body in horizontal and vertical directions is measured. The acoustic target intensity measuring device and method can realize acoustic target intensity measurement of a weak scattering body in various postures.

Description

Technical Field

[0001] This invention relates to a technique for measuring the acoustic intensity of aquatic organisms, and more particularly to a device and method for measuring the acoustic intensity of weak scattering bodies. Background Technology

[0002] A sudden increase in marine life can clog the intake of nuclear power plants, hindering the operation of filtration systems and potentially causing emergency shutdowns of multiple units, thus disrupting the normal operation of the nuclear power plant. Plankton such as shrimp, jellyfish, and algae are the main factors causing intake blockages in my country's nuclear power plants. Detection of plankton in water can be achieved by measuring the intensity of their acoustic targets; however, this method requires prior measurement of the acoustic intensity of the target organisms.

[0003] The current problem is that existing testing methods and devices are mainly aimed at measuring the acoustic intensity of fish targets. The tools for fixing the target are mostly steel needles and thick ropes, and the main method used is the suspension control method to measure the target. This method is not suitable for weak scattering objects such as plankton, and there is currently no device specifically designed for measuring the acoustic intensity of weak scattering objects such as plankton. Summary of the Invention

[0004] The purpose of this invention is to provide a device for measuring the acoustic intensity of a weak scattering object, which can measure the acoustic intensity of a weak scattering object under various attitudes.

[0005] The present invention also aims to provide a method for measuring the acoustic intensity of a weak scattering object, which is based on the acoustic intensity measuring device to measure the acoustic intensity of the weak scattering object.

[0006] To achieve the above technical objectives, the present invention adopts the following technical solution:

[0007] A device for measuring the intensity of a weakly scattering acoustic target includes a mounting base, a rotating ring, and a transducer;

[0008] The rotating ring is rotatably mounted on the mounting base, and the rotating ring is driven to rotate by a driving device;

[0009] The rotating ring is provided with a suspension wire rotation mechanism, which includes a thin wire and a mechanism for driving the thin wire to rotate. The thin wire of the suspension wire rotation mechanism passes through the center of the rotating ring.

[0010] The transducer is installed based on a displacement mechanism. The transducer's detection direction is towards the center of the rotating ring. Under the driving action of the displacement mechanism, the transducer can move closer to or further away from the center of the rotating ring.

[0011] Furthermore, the mounting base is the first gantry crane.

[0012] Furthermore, the transducer is installed based on a displacement mechanism, and its specific structural form is as follows: the displacement mechanism is a second trolley, the transducer is installed on the second trolley, and the reciprocating movement of the second trolley can drive the transducer to move closer to or away from the center of the rotating ring.

[0013] Furthermore, the transducer is installed based on a displacement mechanism, specifically implemented as follows: the displacement mechanism is a telescopic device, and the transducer is installed on the mounting base through the telescopic device. The telescopic movement of the telescopic device can drive the transducer to move closer to or away from the center of the rotating ring.

[0014] Furthermore, the suspension rotation mechanism includes two rotatable wire clamps mounted on a swivel and a thin wire;

[0015] Two wire clamps are symmetrically arranged on the rotating ring. The two wire clamps clamp and fix the two ends of the thin wire, and make the thin wire taut. The taut thin wire passes through the center of the rotating ring. A second drive motor is configured for each wire clamp. The second drive motor is mounted on the rotating ring. The wire clamp is driven to rotate by the second drive motor. The two wire clamps rotate simultaneously, in the same direction and at the same speed, so that the thin wire between the two wire clamps can rotate around its own central axis.

[0016] Furthermore, the thin line used in the suspension rotation mechanism is a fishing line.

[0017] Furthermore, an inclinometer is provided at the transducer.

[0018] Furthermore, the rotating ring is driven to rotate by a stepper motor.

[0019] Furthermore, the suspension rotation mechanism is driven by a stepper motor.

[0020] A method for measuring the intensity of a weakly scattering acoustic target, the method being based on the aforementioned acoustic target intensity measuring device, the method comprising:

[0021] According to the formula

[0022]

[0023] The minimum far-field distance of the transducer is calculated, where l is the minimum far-field distance of the transducer, D is the diameter of the transducer, λ is the wavelength of the incident sound wave, and λ=c / f, f is the center frequency of the transducer, and c is the speed of sound.

[0024] Based on the minimum far-field distance l of the transducer, adjust the distance between the transducer and the center of the rotating ring so that the distance between the transducer and the center of the rotating ring is greater than L;

[0025] The target weak scatterer is fixed on a thin line, and the thin line is fixed in a suspension rotation mechanism. The target weak scatterer is placed in water at a distance of 3 meters from the water surface.

[0026] Select the acoustic target intensity of the weak scattering object in the horizontal or vertical direction according to the test requirements, and send instructions from the host computer to control the system synchronously.

[0027] Once the rotating ring stabilizes, the suspension rotation mechanism controls the rotation to one revolution, simultaneously activating the transducer to emit sound waves toward the weakly scattering target. The transducer operation software then saves the real-time measured acoustic target intensity and the corresponding degree of the rotation mechanism to a table.

[0028] In the acoustic target intensity measuring device of the present invention, a rotating ring and a transducer are provided. A suspension line rotation mechanism is also provided on the rotating ring, wherein the fishing line is used to fix the weak scattering object as the measurement target. By controlling the operation of the rotating ring and the suspension line rotation mechanism, the attitude of the weak scattering object can be controlled. The detection direction of the transducer is towards the weak scattering object. In this way, the acoustic target intensity of the weak scattering object under various attitudes can be measured. The acoustic target intensity data of the weak scattering object under various attitudes are used to construct the acoustic model of the weak scattering object, thereby estimating the target intensity of weak scattering objects of different sizes, and further assessing the resource quantity, density and distribution of weak scattering objects in the target sea area.

[0029] Compared with the prior art, the acoustic target intensity measurement device and method of the present invention have the following advantages: they can realize the measurement of acoustic target intensity of weak scattering objects such as planktonic organisms under various postures. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the weak scatterer acoustic target intensity measuring device of the present invention. Detailed Implementation

[0031] The present invention will be further illustrated below with specific embodiments:

[0032] This embodiment provides a device for measuring the acoustic intensity of a weak scattering object, which is used to measure the acoustic intensity of a weak scattering object.

[0033] See Figure 1 The acoustic target intensity measuring device in this embodiment mainly includes a trolley 1, a rotating ring 3, and a transducer 8.

[0034] Those skilled in the art will understand that the crane 1 itself is a piece of existing technology equipment. Generally speaking, a track is set on the ground of the work area or on the cross beam. The crane 1 is placed based on the track and can make reciprocating linear displacement movement based on the track.

[0035] In this embodiment, two traveling cars 1 are provided. These two traveling cars 1 are arranged side by side, or in other words, the two traveling cars 1 are placed on the same track. The two traveling cars 1 can move towards each other or move away from each other.

[0036] These two traveling cranes 1 are used to install the rotating ring 3 and the transducer 8, respectively. For ease of description, the traveling crane used to install the rotating ring 3 is referred to as the first traveling crane, and the traveling crane used to install the transducer 8 is referred to as the second traveling crane.

[0037] The rotating ring 3 is circular in shape. It is rotatably mounted on the first trolley via two brackets and is driven to rotate by the first drive motor 2 mounted on the first trolley.

[0038] More specifically,

[0039] Transmission teeth are provided on the outer circumference of the rotating ring 3, making the entire rotating ring 3 resemble a large hollow gear. The previously mentioned "the rotating ring 3 is rotatably mounted on the first gantry crane via two brackets" specifically refers to this: the two brackets are fixedly mounted on the first gantry crane, each bracket is equipped with pulleys, and the rotating ring 3 is provided with an annular slide rail. The slide rail on the rotating ring 3 is assembled with the pulleys on the two brackets, thus achieving the mounting of the rotating ring 3 on the first gantry crane. Furthermore, based on the pulleys of the two brackets, the rotating ring 3 can rotate.

[0040] A gear transmission mechanism is also provided on the first tractor. This gear transmission mechanism meshes with the transmission teeth of the rotating ring 3. The gear transmission mechanism is connected to the first drive motor 2, which can drive the rotating ring 3 to rotate through the gear transmission mechanism.

[0041] The first drive motor 2 is a stepper motor. In other embodiments, other drive devices may also be used to drive the rotating ring 3 to rotate.

[0042] The swivel 3 is also equipped with a mechanism specifically for "installing the fishing line, tautning the fishing line, and rotating the fishing line around its own central axis". In this embodiment, this mechanism is referred to as the "suspension line rotation mechanism".

[0043] The suspension line rotating mechanism is equipped with a taut fishing line 5, which passes through the center (center) of the swivel 3. The suspension line rotating mechanism is also equipped with a rotating drive mechanism that drives the fishing line 5 to rotate around its own central axis.

[0044] Specifically

[0045] The suspension line rotation mechanism includes two rotatable line clamps 6 mounted on a rotating ring 3 and a fishing line 5. The line clamps 6 clamp and fix the fishing line 5. The two line clamps 6 are symmetrically arranged on the rotating ring 3, clamping and fixing both ends of the fishing line 5 and keeping the fishing line 5 taut. The taut fishing line 5 passes through the center (center) of the rotating ring 3. A second drive motor 4 is also configured for each line clamp 6, i.e., two second drive motors 4, which are also mounted on the rotating ring 3. The second drive motors 4 drive the corresponding line clamp 6 to rotate. The line clamps 6 rotate under the drive of the second drive motors 4. When the two line clamps 6 rotate simultaneously, in the same direction, and at the same speed, the fishing line 5 between them rotates around its own central axis.

[0046] The second drive motor 4 is a stepper motor.

[0047] It should be noted that in this embodiment, both the rotating ring 3 and the suspension rotation mechanism mounted on it are controlled by stepper motors, which is beneficial for accurately controlling the posture of the target measurement object.

[0048] The transducer 8 is a prior art device whose function is to "detect the acoustic target intensity of the target object by emitting continuous acoustic signals to the target object".

[0049] In this embodiment, the transducer 8 is also mounted on the second trolley via a bracket, and the transducer 8 faces the center (center) of the swivel 3 on the first trolley, or in other words, the midpoint of the taut fishing line 5.

[0050] The acoustic target intensity measuring device of this embodiment is used to measure the acoustic target intensity of a weak scattering body, and in particular, to measure the acoustic target intensity of a weak scattering body in various postures.

[0051] It should be noted that the acoustic target intensity is a technical term in this field, which refers to "the intensity of the echo reflected by an object".

[0052] The weak scatterer refers to an object with a weak acoustic target intensity. In this embodiment, it refers to some "plankton". Plankton generally has a weak echo intensity and is a weak scatterer.

[0053] The following uses a shrimp as an example to illustrate the specific functions of the acoustic target intensity measuring device in this embodiment:

[0054] See Figure 1The shrimp 10, which serves as the measurement target, is fixed to the fishing line 5 (in this embodiment, the fishing line is wrapped around the shrimp several times and tied to the fishing line), and the shrimp 10 is positioned at the center of the rotating ring 3. Then, by controlling the rotation of the rotating ring 3 and the rotation of the fishing line 5, the shrimp 10 is controlled to face the transducer 8 in a suitable posture. Then, the first and second carriages are controlled to move to control the distance between the transducer 8 and the shrimp 10 to reach the required suitable distance. Finally, the transducer 8 is controlled to detect the shrimp 10, thereby detecting the acoustic target intensity of the shrimp 10 in a certain posture.

[0055] After measuring the acoustic target intensity in one posture, the shrimp 10 can be controlled to face the transducer 8 in another posture, and the acoustic target intensity in that other posture can be measured again, until all target postures are measured (usually six directions: up, down, left, right, front, and back). This allows for the measurement of the acoustic target intensity of the shrimp 10 in various postures. The measured acoustic target intensity data of the shrimp 10 in various postures are used to construct an acoustic model of the shrimp, thereby estimating the target intensity of shrimp of different sizes, and further assessing the resource quantity, density, and distribution of shrimp in the target sea area.

[0056] Preferably, an inclinometer 7 is also provided at the transducer 8. The inclinometer 7 is used to measure the tilt angle of the transducer 8. Furthermore, an angle adjustment mechanism is provided on the bracket on which the transducer 8 is mounted, which can adjust the tilt angle of the transducer 8. When the operator observes that the inclinometer 7 shows that the transducer 8 has a tilt angle, the tilt angle of the transducer 8 can be adjusted by adjusting the angle adjustment mechanism to prevent the tilt angle of the transducer 8 from being too large, which would lead to inaccurate measurement data.

[0057] In other embodiments, the rotating ring 3 and the transducer 8 can be mounted on the same trolley 1. The bracket for mounting the transducer 8 can be mounted on the trolley 1 by a telescopic device (such as a hydraulic cylinder, pneumatic cylinder, electric cylinder, etc.). Driven by the telescopic device, the transducer 8 can move closer to or further away from the center of the rotating ring 3, thereby achieving the effect of adjusting the distance between the transducer 8 and the measurement target.

[0058] In general, the specific installation structure of transducer 8 can be achieved as long as it can achieve the following: "transducer 8 is installed based on displacement mechanism, transducer 8 is located on the side of the center of rotating ring 3, and the detection direction of transducer 8 is towards the center of rotating ring 3, and under the driving action of displacement mechanism, transducer 8 can move closer to or away from the center of rotating ring 3".

[0059] The displacement mechanism described here is a summary of the previously mentioned "second trolley" and "telescopic device".

[0060] It should be noted that the purpose of achieving the effect of "transducer 8 being able to approach or move away from the center of the rotating ring 3" is to adjust the distance between transducer 8 and the target shrimp 10 so that it is always in the far field.

[0061] It should be noted that the size of the rotating ring 3 can be determined based on the beam opening angle of the transducer 8 and the size of the water tank used for testing. Specifically, it can be determined according to the formula...

[0062]

[0063] The minimum diameter d of the rotating ring 3 is calculated using the formula, where θ is the opening angle of the transducer 8, and S is the distance from the transducer 8 to the weak scattering target. To prevent the rotating ring 3 from affecting the experimental results, its diameter must be greater than d.

[0064] It should be noted that in other embodiments, the rotating ring 3 and the transducer 8 do not necessarily have to be mounted on the trolley 1 as the mounting base. Other types of mounting bases can also be used, such as a trolley with rollers.

[0065] It should be noted that in other embodiments, other types of thin thread can be used instead of fishing line.

[0066] This embodiment also provides a method for measuring the intensity of a weakly scattering acoustic target. This method is implemented based on the aforementioned acoustic target intensity measuring device, and specifically includes:

[0067] According to the formula

[0068]

[0069] The minimum far-field distance of the transducer is calculated, where L is the minimum far-field distance of the transducer, D is the diameter of the transducer, λ is the wavelength of the incident sound wave, and λ=C / f, F is the center frequency of the transducer, and c is the speed of sound.

[0070] Based on the calculated minimum far-field distance L of the transducer, the distance between the transducer 8 and the center of the rotating ring 3 is adjusted to adjust the distance between the transducer 8 and the weak scatterer of the measurement target. The distance between the two must be greater than l so that the weak scatterer of the measurement target is located in the far field.

[0071] The target weak scatterer is fixed on the fishing line 5, and the fishing line 5 is fixed in the suspension rotation mechanism. The target weak scatterer is placed in the water, about 3 meters above the water surface, in order to reduce the influence of water surface reflection on the test results.

[0072] At the start of the test, the transducer 8 is calibrated using the inclinometer 7 to ensure that the center of the transducer 8 is not on the same plane as the center of the weak scatterer of the target object. After the transducer 8 is calibrated, the rotating ring 3 is calibrated, and the position shown in the figure is defined as 0° of the system.

[0073] Testers select the acoustic target intensity of the weak scattering object in the horizontal or vertical direction according to the test requirements, and the host computer issues instructions to the synchronous control system.

[0074] Once the rotating ring 3 is stable, the suspension rotating mechanism controls the rotation to one revolution, and at the same time, the transducer 8 is turned on, causing the transducer 8 to emit sound waves toward the weak scattering target. The real-time measured acoustic target intensity and the corresponding degree of the rotating mechanism are saved to a table through the transducer operation software.

[0075] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A device for measuring the intensity of a weakly scattering acoustic target, characterized in that: Includes mounting base, rotating ring (3) and transducer (8); The rotating ring (3) is rotatably mounted on the mounting base, and the rotating ring (3) is driven to rotate by a driving device; The rotating ring (3) is provided with a suspension wire rotation mechanism. The suspension wire rotation mechanism is provided with a thin wire and a mechanism for driving the thin wire to rotate. The thin wire of the suspension wire rotation mechanism passes through the center of the rotating ring (3). The transducer (8) is installed based on a displacement mechanism. The detection direction of the transducer (8) is towards the center of the rotating ring (3). Under the driving action of the displacement mechanism, the transducer (8) can move closer to or further away from the center of the rotating ring (3).

2. The acoustic target intensity measuring device for weak scatterers according to claim 1, characterized in that: The mounting base is the first traveling crane.

3. The acoustic target intensity measuring device for weak scatterers according to claim 1, characterized in that: The transducer (8) is installed based on a displacement mechanism. The specific structure is as follows: the displacement mechanism is a second trolley, and the transducer (8) is installed on the second trolley. The reciprocating movement of the second trolley can drive the transducer (8) to move closer to or away from the center of the rotating ring (3).

4. The acoustic target intensity measuring device for weak scatterers according to claim 1, characterized in that: The transducer (8) is installed based on a displacement mechanism. The specific structure is as follows: the displacement mechanism is a telescopic device. The transducer (8) is installed on the mounting base through the telescopic device. The telescopic action of the telescopic device can drive the transducer (8) to move closer to or away from the center of the rotating ring (3).

5. The acoustic target intensity measuring device for weak scatterers according to claim 1, characterized in that: The suspension wire rotation mechanism includes two rotatable wire clamps (6) mounted on a swivel (3) and a thin wire; Two wire clamps (6) are arranged symmetrically on the rotating ring (3). The two wire clamps (6) clamp and fix the two ends of the thin wire, and make the thin wire taut. The taut thin wire passes through the center of the rotating ring (3). A second drive motor (4) is configured for each wire clamp (6). The second drive motor (4) is mounted on the rotating ring (3). The wire clamps (6) are driven to rotate by the second drive motor (4). The two wire clamps (6) rotate simultaneously, in the same direction and at the same speed, so that the thin wire between the two wire clamps (6) can rotate around its own central axis.

6. The acoustic target intensity measuring device for weak scatterers according to claim 1, characterized in that: The thin line used in the suspension rotation mechanism is a fishing line (5).

7. The acoustic target intensity measuring device for weak scatterers according to claim 1, characterized in that: An inclinometer (7) is installed at the transducer (8).

8. The acoustic target intensity measuring device for weak scatterers according to claim 1, characterized in that: The rotating ring (3) is driven to rotate by a stepper motor.

9. The acoustic target intensity measuring device for weak scatterers according to claim 1, characterized in that: The suspension rotation mechanism is driven by a stepper motor.

10. A method for measuring the intensity of a weakly scattering acoustic target, the method being based on the acoustic target intensity measuring device as described in claim 1, characterized in that: The acoustic target intensity measurement method includes: According to the formula The minimum far-field distance of the transducer (8) is calculated. In the formula, l is the minimum far-field distance of the transducer, D is the diameter of the transducer, λ is the wavelength of the incident sound wave, and λ=c / f, f is the center frequency of the transducer, and c is the speed of sound. Based on the minimum far-field distance l of the transducer, adjust the distance between the center of the transducer (8) and the center of the rotating ring (3) so that the distance between the center of the transducer (8) and the center of the rotating ring (3) is greater than l; The target weak scatterer is fixed on a thin line, and the thin line is fixed in a suspension rotation mechanism. The target weak scatterer is placed in water at a distance of 3 meters from the water surface. Select the acoustic target intensity of the weak scattering object in the horizontal or vertical direction according to the test requirements, and send instructions from the host computer to control the system synchronously. Once the rotating ring (3) is stable, the suspension rotating mechanism controls the rotation to one revolution, and at the same time, the transducer (8) is turned on, so that the transducer (8) emits sound waves to the weak scattering target of the measurement, and the real-time measured acoustic target intensity and the corresponding degree of the rotating mechanism are saved to the table through the transducer operation software.

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