Pulse sound field acquisition method and system

Abstract

The application provides a pulse sound field acquisition method and system, the method comprises the following steps: obtaining the positional relationship between a transducer and a hydrophone; determining the first distance of the axial offset of the hydrophone, the second distance and the third distance corresponding to the nearest sound source point and the farthest sound source point in the radial direction based on the positional relationship between the transducer and the hydrophone; if the positional offset of the hydrophone is monitored, determining the first delay of the axial offset of the hydrophone according to the first distance, and determining the second delay according to the time of the second distance and the third distance of the hydrophone; performing delay compensation on the hydrophone according to the first delay in the axial direction and the second delay in the radial direction, scanning the line surface body of the transducer to acquire the pulse sound field, and making real-time delay compensation on the axial direction and the radial direction of the hydrophone, so that the sound field information collected at any position is at the same pulse moment and the same pulse number, which not only ensures the accuracy of the pulse sound field acquisition, but also improves the acquisition efficiency.

Description

Technical Field

[0001] This invention relates to the field of sound field measurement technology, particularly to sound field measurement of focused ultrasound, and specifically to a pulse sound field acquisition method and system. Background Technology

[0002] High-intensity focused ultrasound (HIFU) is widely used in ultrasound therapy, primarily utilizing a focused focal point for high-temperature ablation treatment. The acoustic field of HIFU is crucial to the safety and effectiveness of the treatment and is closely related to related acoustic research. The acoustic field characteristics of HIFU are mainly measured using hydrophones to determine its sound pressure distribution and acoustic field. Currently, during HIFU scanning, a continuous drive signal is typically used to drive the transducer to generate a continuous wave acoustic field. However, when scanning acoustic field data along the acoustic axis, the sound field information reflected from obstacles can disturb the accuracy of the data at the acquisition point. Furthermore, prolonged continuous high-power drive of the transducer can also affect its performance. Therefore, a new pulsed acoustic field acquisition scheme is urgently needed to improve the accuracy of pulsed information acquisition. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the present invention provides a pulse sound field acquisition method and system to solve the technical problem of low accuracy in pulse sound field acquisition.

[0004] In a first aspect, the present invention provides a pulse sound field acquisition method, the method comprising: acquiring the positional relationship between a transducer and a hydrophone; determining in real time, based on the positional relationship between the transducer and the hydrophone, a first axial offset distance of the hydrophone, and a second and third radial distances corresponding to the nearest and farthest sound source points, respectively; if a positional offset of the hydrophone is detected, determining a first axial delay of the hydrophone based on the first distance, and determining a second delay based on the time of the hydrophone relative to the second and third distances, respectively; performing delay compensation on the hydrophone in real time based on the first axial delay and the second radial delay, and scanning the transducer's line, surface, and volume to acquire a pulse sound field.

[0005] In one embodiment of the present invention, before obtaining the positional relationship between the transducer and the hydrophone, the method further includes: configuring the transducer drive pulse to a preset number of cycles, so that the hydrophone collects pulses within the preset number of cycles.

[0006] In one embodiment of the present invention, determining the first axial offset distance of the hydrophone in real time based on the positional relationship between the transducer and the hydrophone includes: determining the vertical distance from the central acoustic axis of the hydrophone to the lowest concave point of the transducer, and the axial height from the surface of the transducer to the lowest concave point of the transducer; determining the vertical height of the hydrophone to the surface of the transducer based on the vertical distance and the axial height; determining the axial offset distance of the hydrophone based on the vertical height; and determining the first axial offset distance of the hydrophone based on the axial offset distance.

[0007] In one embodiment of the present invention, the determination of a second distance and a third distance in the radial direction corresponding to the nearest sound source point and the farthest sound source point, respectively, based on the positional relationship between the transducer and the hydrophone, includes: determining a first moving distance of the hydrophone in the X-axis direction and a second moving distance in the Y-axis direction in the radial dimension; performing a root operation on the sum of the squares of the first moving distance and the second moving distance to determine the radial offset distance of the hydrophone; performing a root operation on the sum of the squares of the difference between the radius of the transducer and the radial offset distance and the vertical height to determine the second distance of the hydrophone in the radial direction to the nearest sound source point; and performing a root operation on the sum of the squares of the radius of the transducer and the radial offset distance and the vertical height to determine the third distance of the hydrophone in the radial direction to the farthest sound source point.

[0008] In one embodiment of the present invention, determining a first axial delay of the hydrophone based on the first distance, and determining a second delay based on the time of the hydrophone relative to the second distance and the third distance respectively, includes: determining the first axial delay of the hydrophone based on a first ratio of the first distance to the speed of sound; determining the pulse duration based on a preset number of cycles of the transducer driving pulse and the current pulse frequency; determining a second ratio of the second distance to the speed of sound and a third ratio of the third distance to the speed of sound; forming a delay compensation interval by summing the second ratio, the third ratio, and the pulse duration, and determining the second delay based on the delay compensation interval.

[0009] In one embodiment of the present invention, the hydrophone is subjected to real-time delay compensation according to a first delay in the axial direction and a second delay in the radial direction, and the transducer is scanned to collect a pulse sound field. This includes: performing real-time delay compensation on the hydrophone in the axial direction and the radial direction according to the first delay and the second delay, respectively, and triggering the hydrophone by delay so that the pulse sound field collected by pulses at different positions carries the same pulse time and the same number of pulses.

[0010] In one embodiment of the present invention, configuring the transducer drive pulse to a preset number of cycles so that the hydrophone collects pulses within the preset number of cycles includes: configuring the transducer drive pulse to a preset number of cycles of 20-50 so that the hydrophone collects pulses in the latter half of the preset number of cycles.

[0011] In one embodiment of the present invention, after acquiring the pulsed sound field, the method further includes: calculating sound field parameters based on the radial and axial sound pressure distribution of the pulsed sound field, measuring the performance parameters of the transducer's sound field characteristics, and generating an evaluation result; wherein the transducer is a focusing transducer, and the performance parameters of the focusing transducer's sound field include the major axis dimension of the focal region, the axial sub-maximum sound pressure and attenuation of the focal region, the width of the focal plane, the highest sidelobe sound pressure and attenuation, the focal region area, the focal region sound intensity distribution and corresponding sound power under the current excitation, and the symmetry of the sound field's focal plane.

[0012] In a second aspect, the present invention provides a pulse sound field acquisition system, the system comprising: a position determination module for acquiring the positional relationship between a transducer and a hydrophone; a distance determination module for determining, in real time, a first axial offset distance of the hydrophone, and second and third radial distances corresponding to the nearest and farthest sound source points, respectively, based on the positional relationship between the transducer and the hydrophone; a delay determination module for determining, if the positional offset of the hydrophone is detected, a first axial delay of the hydrophone based on the first distance, and a second delay based on the time of the hydrophone relative to the second and third distances respectively; and a sound field acquisition module for performing delay compensation on the hydrophone in real time based on the first axial delay and the second radial delay, and scanning the transducer's lines, surfaces, and volumes to acquire a pulse sound field.

[0013] In one embodiment of the present invention, the system further includes: a hydrophone that receives the ultrasonic signal from the transducer, the hydrophone being suspended in the liquid perpendicular to the fluid-solid interface and located on the central axis of the transducer; a three-dimensional motion control module controls a dual-axis lead screw slide to move the hydrophone; the three-dimensional motion control module consists of three sets of identical devices, which respectively control the precise movement of the hydrophone in the X-axis, Y-axis and Z-axis directions; each set of devices is driven by a stepper motor to move the slide via a lead screw transmission.

[0014] The beneficial effects of this invention are as follows: The first axial offset distance of the hydrophone is determined in real time by the positional relationship between the transducer and the hydrophone; the second and third radial distances correspond to the nearest and farthest sound source points, respectively; a first axial delay of the hydrophone is determined based on the first distance; and a second delay is determined based on the time taken between the hydrophone and the second and third distances, respectively; delay compensation is performed on the hydrophone in real time based on the first axial delay and the second radial delay, and the transducer's line and surface volume is scanned to acquire a pulse sound field. Through this pulse sound field acquisition system, on the one hand, manual intervention is avoided, improving the efficiency of pulse sound field acquisition; on the other hand, the real-time measurement of the hydrophone's position relative to the transducer and the calculation of the pulse arrival time at different positions allow for adjustment of the hydrophone's acquisition pulse delay, which is then compensated in real time for the acquisition trigger delay. This ensures that the sound field information acquired at any position has the same pulse time and the same number of pulses, and that the acquired sound field information includes all sound source information, thus ensuring the accuracy of pulse sound field acquisition.

[0015] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0017] Figure 1 This is a schematic flowchart illustrating a pulse sound field acquisition method according to an exemplary embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram illustrating the complete process of a pulse sound field acquisition method according to an exemplary embodiment of the present invention;

[0019] Figure 3 This is an exemplary embodiment of the present invention illustrating the correlation between a pulse excitation signal and hydrophone acquisition;

[0020] Figure 4 This is an exemplary embodiment of the present invention, illustrating the positional relationship between a transducer and a hydrophone.

[0021] Figure 5 This is a schematic diagram of a pulse sound field acquisition system structure, illustrating an exemplary embodiment of the present invention.

[0022] Figure 6This is a schematic diagram of a pulse sound field acquisition system, illustrating an exemplary embodiment of the present invention. Detailed Implementation

[0023] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0024] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the shape, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0025] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0026] In this invention, the term "and / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The character " / " generally indicates that the preceding and following associated objects have an "or" relationship.

[0027] The present invention will now be described in detail through specific embodiments. Please refer to [link / reference]. Figure 1 As shown, Figure 1 A schematic flowchart of a pulse sound field acquisition method provided in an embodiment of the present invention includes the following steps:

[0028] Step S101: Obtain the positional relationship between the transducer and the hydrophone;

[0029] For example, the positions of the transducer and hydrophone can be accurately measured and recorded using high-precision measuring tools to determine their positional relationship; or, markers can be placed on the transducer and / or hydrophone, and then the position and trajectory of the markers can be tracked using a laser tracker or motion capture system to accurately measure their positional relationship; or, the propagation characteristics of sound waves can be utilized to determine their distance and direction by measuring the time required for sound waves to travel from the transducer to the hydrophone, thus determining their positional relationship.

[0030] A hydrophone is a device used to receive and detect underwater acoustic signals; it is also called an underwater sonar or underwater acoustic transducer. Transducers include focusing transducers, which are devices that convert electrical energy into acoustic energy or vice versa. They are commonly used in acoustic or ultrasonic applications. Focusing transducers are typically made of piezoelectric materials and generate sound waves by applying electrical signals, or receive sound waves and convert them into electrical signals.

[0031] Step S102: Based on the positional relationship between the transducer and the hydrophone, determine in real time the first distance of the hydrophone offset in the axial direction, and the second and third distances in the radial direction corresponding to the nearest and farthest sound source points, respectively.

[0032] Specifically, based on the acquired positional relationship data between the transducer and the hydrophone, the axial offset distance of the hydrophone relative to the transducer, i.e., the first distance, is calculated. Simultaneously, based on the sound wave propagation path emitted by the transducer and the positional relationship of the hydrophone, the distances from the hydrophone to the nearest and farthest sound source points, i.e., the second and third distances, are calculated. During real-time monitoring, the positional relationship data between the transducer and the hydrophone is continuously acquired, and the axial offset distance of the hydrophone, as well as the distances to the nearest and farthest sound source points, are calculated in real time. If any abnormalities or deviations are detected, adjustments and handling can be made promptly to ensure the normal operation of the system and accurate measurements.

[0033] Step S103: If a positional shift of the hydrophone is detected, the first axial delay of the hydrophone is determined based on the first distance, and the second delay is determined based on the time of the hydrophone relative to the second distance and the third distance, respectively.

[0034] Specifically, by monitoring the positional relationship between the transducer and the hydrophone in real time, it is determined whether the position of the hydrophone has shifted. If a positional shift is detected, the first axial delay of the hydrophone can be calculated based on the first distance (i.e., the axial offset distance). The first delay is calculated based on the speed of sound propagation in water and the first distance. A second delay can also be calculated based on the distances between the hydrophone and the nearest and farthest sound source points (i.e., the second and third distances), which are also calculated based on the speed of sound propagation in water and the distance.

[0035] Step S104: The hydrophone is compensated for delay in real time according to the first delay in the axial direction and the second delay in the radial direction, and the transducer is scanned to collect the pulse sound field.

[0036] Specifically, based on the calculated first delay and second delay, it is determined whether adjustments or corresponding processing measures are needed. For example, the hydrophone is compensated for delay in real time in the axial and radial directions according to the first delay and the second delay, respectively. The hydrophone is triggered by the delay so that the pulse sound field collected from pulses at different positions carries the same pulse time and the same number of pulses.

[0037] In this embodiment, the first axial offset distance of the hydrophone is determined in real time based on the positional relationship between the transducer and the hydrophone. The second and third radial distances to the nearest and farthest sound source points are also determined. A first axial delay of the hydrophone is determined based on the first distance, and a second delay is determined based on the time taken between the hydrophone and the second and third distances. The hydrophone is then compensated for the delay in real time based on the first axial delay and the second radial delay, and the transducer's lines and surfaces are scanned to acquire a pulse sound field. This pulse sound field acquisition system avoids manual intervention, improving acquisition efficiency. Furthermore, by measuring the hydrophone's position relative to the transducer in real time and calculating the pulse arrival time at different positions, the system adjusts the acquisition pulse delay according to this time, compensating for it in real time in the acquisition trigger delay. This ensures that the sound field information acquired at any position has the same pulse time and the same number of pulses, and that the acquired sound field information includes all sound source information, thus ensuring the accuracy of pulse sound field acquisition.

[0038] Based on the above embodiments, before obtaining the positional relationship between the transducer and the hydrophone, the method further includes:

[0039] Configure the transducer drive pulse to a preset number of cycles so that the hydrophone can collect pulses within the preset number of cycles.

[0040] Specifically, configuring the transducer drive pulse to a preset number of cycles so that the hydrophone collects pulses within the preset number of cycles includes: configuring the transducer drive pulse to a preset number of cycles of 20-50 so that the hydrophone collects pulses in the latter half of the preset number of cycles.

[0041] For example, based on actual needs, select a suitable preset number of cycles, such as 20-50. Determine that pulses are collected in the latter half of the preset number of cycles, for example, through programming or configuration software. Once the transducer drive pulses are configured to the preset number of cycles and an appropriate time window is set, start the hydrophone to collect pulses.

[0042] In this embodiment, setting an appropriate number of driving pulse cycles is to ensure the integrity of the acquired sound field information. It is necessary to ensure that the sound wave information from each sound source point of the transducer reaches the measurement point, and also to ensure that the measured pulse data contains only sound field information and no electromagnetic interference information from the transducer. Therefore, a better method for setting the number of pulse cycles is: 20-50 cycles of transducer driving pulses, and the last 10 cycles of pulse information collected by the hydrophone.

[0043] In some embodiments, determining a first axial offset distance of the hydrophone in real time based on the positional relationship between the transducer and the hydrophone includes:

[0044] Determine the vertical distance from the center acoustic axis of the hydrophone to the lowest point of the transducer, and the axial height from the surface of the transducer to the lowest point of the transducer;

[0045] The vertical height of the hydrophone to the transducer surface is determined based on the vertical distance and axial height.

[0046] The axial offset distance of the hydrophone is determined based on the vertical height.

[0047] The first distance of the hydrophone in axial offset is determined based on the axial offset distance.

[0048] Specifically, the vertical distance is obtained through direct measurement or by using measuring tools. The axial height from the transducer surface to the lowest point of the transducer is also determined through direct measurement or by using measuring tools. Based on the vertical distance and axial height, the vertical height from the hydrophone to the transducer surface is determined; that is, vertical height = vertical distance + axial height. Thus, the vertical height from the hydrophone to the transducer surface is obtained.

[0049] If the ideal vertical height between the hydrophone and the transducer is known, and the actual vertical height deviates from the ideal value, then this deviation can be used to calculate the axial offset distance. Specifically, the axial offset distance = ideal vertical height - actual vertical height. If the axial offset distance is known, then this distance can be used as the first distance of the hydrophone's axial offset.

[0050] Through the above steps, the first axial offset distance of the hydrophone is calculated based on the positional relationship between the hydrophone and the transducer. It should be noted that the specific values ​​in these steps need to be determined based on the actual situation and measurement accuracy. Furthermore, to ensure the accuracy and reliability of the results, it is recommended to use high-precision tools and equipment during the measurement and calculation process, and to perform necessary calibration and verification.

[0051] Please see Figure 2 This is a schematic diagram illustrating the complete process of a pulse sound field acquisition method according to an exemplary embodiment of the present invention, including:

[0052] Step 1: Set an appropriate number of drive pulse cycles;

[0053] Step 2: The hydrophone is positioned at the center acoustic axis to measure the distance to the surface of the Huaneng heating radiator;

[0054] Step 3: ΔT, i.e., the first delay, is calculated by the z-axis motion ΔS of the hydrophone during acoustic axis scanning; delays t1 and t2, i.e., the second delay, are calculated by the three-dimensional motion system Δx and Δy of the hydrophone during radial scanning; the acquisition delay range is adjusted in real time according to the positional relationship to acquire the sound field.

[0055] Specifically, by combining the displacement information (Δx, Δy) of the three-dimensional motion system during radial scanning, the second delays t1 and t2 can be calculated. At the same time, the range of the acquired delays is adjusted in real time to ensure the accuracy and integrity of the data.

[0056] Step 4: Move to the next measurement point using a high-precision three-dimensional motion system;

[0057] Specifically, in order to achieve automated and efficient sound field data acquisition, a high-precision three-dimensional motion system can be used to accurately move to the preset measurement point, avoiding errors caused by human operation and improving the consistency and repeatability of the data.

[0058] Step 5: Repeat steps 2-4 to perform line, surface, and volume scans of the transducer sound field.

[0059] Specifically, by scanning lines, surfaces, and volumes, the distribution and characteristics of the sound field can be analyzed from multiple dimensions.

[0060] See details Figure 3This is an exemplary embodiment of the present invention illustrating a correlation diagram between a pulse excitation signal and a hydrophone acquisition. The distance from the transducer to the hydrophone is determined based on the time difference between the pulse excitation signal and the signal acquired by the hydrophone. This method allows for the initial setting of the acquisition delay. Specifically, the hydrophone is first positioned at the center of the transducer, with the time difference between the pulse excitation signal and the signal acquired by the hydrophone being Δt. Figure 3 The formula for calculating the distance from the transducer to the hydrophone is:

[0061] D=Δt*c

[0062] D is the vertical distance from the hydrophone to the lowest concave point of the transducer, and c is the speed of sound in water. This method can also be applied to acoustic holography to obtain the distance from the scanning holographic surface to the transducer surface.

[0063] In some embodiments, determining in real time, based on the positional relationship between the transducer and the hydrophone, the second and third distances corresponding to the nearest and farthest sound source points in the radial direction, respectively, includes:

[0064] Determine the first movement distance of the hydrophone in the X-axis direction and the second movement distance in the Y-axis direction in the radial dimension;

[0065] The radial offset distance of the hydrophone is determined by performing a root operation on the sum of the squares of the first moving distance and the second moving distance;

[0066] The second distance of the hydrophone to the nearest sound source is determined by taking the root of the sum of the squares of the vertical height based on the difference between the radius of the transducer and the radial offset distance.

[0067] The third distance of the hydrophone from the farthest sound source point in the radial direction is determined by performing a root operation on the sum of the transducer's radius and the radial offset distance, and the sum of the squares of the vertical height.

[0068] Specifically, if the hydrophone moves in the X-axis direction, whether the distance is positive or negative, the absolute value of the movement is the first movement distance. Similarly, the second movement distance can be obtained by measuring or using a tracking device if the hydrophone moves in the Y-axis direction.

[0069] The radial offset distance of the hydrophone can be obtained by taking the square root of the movement distance in the X and Y directions.

[0070] The radial distance from the hydrophone to the nearest sound source can be obtained by taking the root of the difference between the transducer radius and the radial offset distance and the sum of the squares of the vertical height; the radial distance from the hydrophone to the farthest sound source can be obtained by taking the root of the sum of the transducer radius and the radial offset distance and the sum of the squares of the vertical height.

[0071] By following the steps above, the radial distances from the hydrophone to the nearest and farthest sound sources can be calculated based on the hydrophone's movement distance and transducer parameters. This information is crucial for acoustic measurement and positioning systems, helping to determine the location of the hydrophone and the sound sources. It is important to note that the specific values ​​in these steps need to be determined based on the actual situation and measurement accuracy.

[0072] In addition, to ensure the accuracy and reliability of the results, it is recommended to use high-precision tools and equipment and perform necessary calibration and verification during the measurement and calculation process.

[0073] In another embodiment, determining a first axial delay of the hydrophone based on the first distance, and determining a second delay based on the time taken by the hydrophone at the second distance and the third distance, respectively, includes:

[0074] The first axial delay of the hydrophone is determined based on the first ratio of the first distance to the speed of sound.

[0075] The pulse duration is determined based on the preset number of cycles of the transducer drive pulse and the current pulse frequency;

[0076] Determine a second ratio of the second distance to the speed of sound and a third ratio of the third distance to the speed of sound;

[0077] The second ratio, the third ratio, and the pulse duration are combined to form a delay compensation interval, and the second delay is determined based on the delay compensation interval.

[0078] In the first implementation, please refer to Figure 4 This is an exemplary embodiment of the present invention illustrating a distribution diagram of the positional relationship between a transducer and a hydrophone, comprising:

[0079] When the hydrophone only changes position along the central acoustic axis, the time delay of the pulse acquisition is automatically adjusted. Compared to previous pulse-driven sound field scanning systems where the driver source simply sets a fixed pulse trigger delay, this method is independent of the driver source and adds an automatic delay compensation module. Figure 4, according to the movement distance ΔS of the three-dimensional motion system controlled by the PC (i.e., the axial offset distance), the time difference of delayed trigger for pulse acquisition at different positions is calculated, and the time difference of delayed trigger is compensated into the set trigger delay. Therefore, the time for the delayed triggering of the acquisition card to collect data at different positions is different, which can compensate for the problem that the pulse signal arrival time varies with distance, and ensure that the sound field information collected by the acquisition card is at the same pulse moment and has the same number of pulses.

[0080] ΔT=ΔS / c

[0081] ΔS is the real-time movement distance of the hydrophone, c is the sound velocity in water, and ΔT is the time difference that needs to be compensated obtained by calculation, that is, the first delay in the axial direction.

[0082] For example, in the second embodiment, when the hydrophone changes position in the radial direction perpendicular to the acoustic axis, since the distances from different sound source points to the measurement point are different at this time, the arrival time of the pulse sound field information at the hydrophone is also different. At this time, in order to ensure that all sound source information can be collected, it is necessary to ensure that the pulse moment for starting collection is after the sound source information from the farthest sound source point reaches the hydrophone and before the pulse information from the nearest sound source point is completely over. The time for the nearest sound source point information to reach the hydrophone is t1, and the time for the farthest sound source point information to reach the hydrophone is t2.

[0083] t1=S1 / C

[0084] t2=S2 / C

[0085] The pulse duration T = n / f is calculated according to the set number of pulses n, where f is the pulse frequency. The time range of the acquisition delay t (i.e., the second delay) adjusted by automatic delay compensation is t2 < t < T + t1, which ensures that the collected sound field information includes all sound source information.

[0086] In some embodiments, after collecting the pulsed sound field, the method further comprises:

[0087] Calculating sound field parameters based on the radial and axial sound pressure distribution of the pulsed sound field, measuring the performance parameters of the sound field characteristics of the transducer, and generating an evaluation result; wherein the transducer is a focusing transducer, and the performance parameters of the sound field of the focusing transducer include the long axis size of the focal region, the secondary maximum sound pressure and attenuation in the axial direction of the focal region, the width of the focal plane, the maximum side lobe sound pressure and attenuation, the area of the focal region, the focal region sound intensity distribution under current excitation and the corresponding sound power, and the symmetry of the focal plane of the sound field.

[0088] In this embodiment, radial and axial sound pressure distribution data of the pulsed sound field emitted by the focusing transducer are obtained through sensors or measuring instruments. Based on the collected sound pressure distribution data, the characteristics of the sound field in the radial and axial directions are analyzed, including, but not limited to, calculating parameters such as the average, maximum, minimum, and standard deviation of the sound pressure, as well as analyzing the shape and symmetry of the sound pressure distribution.

[0089] Based on the analysis results, the acoustic field parameters of the focusing transducer are calculated, such as the major axis dimension of the focal region, the axial sub-maximum sound pressure level and attenuation of the focal region, the width of the focal plane, the highest sidelobe sound pressure level and attenuation, etc. These parameters are used to describe the characteristics and performance of the acoustic field. By measuring the performance parameters of the focusing transducer, such as the focal region area, the focal region sound intensity distribution under the current excitation, and the corresponding sound power, the performance of the focusing transducer can be further evaluated. These parameters can help to understand the energy conversion efficiency and focusing effect of the transducer.

[0090] Based on the calculated sound field parameters and measured performance parameters, the sound field characteristics of the focusing transducer are evaluated. This includes assessing the symmetry of the sound field, focusing effect, energy distribution, etc., as well as comparing the performance differences between different transducers. The evaluation results are presented in the form of reports or charts, providing a comprehensive understanding and analysis of the sound field characteristics of the focusing transducer. The evaluation results can be used to guide the optimization design and performance improvement of the transducer.

[0091] It should be noted that the specific implementation methods in the above steps may vary depending on the actual application scenario and requirements. Therefore, detailed planning and preparation should be carried out before actual operation to ensure the accuracy and reliability of the experimental results.

[0092] Please see Figure 5 The present invention provides a schematic diagram of a pulse sound field acquisition system 500, the system comprising:

[0093] The position determination module 501 is used to obtain the positional relationship between the transducer and the hydrophone.

[0094] For example, before the position determination module 501, the pulse sound field acquisition system 500 also includes a period configuration module, which is used to configure the transducer drive pulse to a preset number of periods so that the hydrophone can acquire pulses within the preset number of periods.

[0095] The distance determination module 502 determines in real time the first distance of the hydrophone offset in the axial direction, and the second and third distances in the radial direction to the nearest sound source point and the farthest sound source point, respectively, based on the positional relationship between the transducer and the hydrophone.

[0096] The delay determination module 503 is used to determine a first delay of the hydrophone in the axial direction based on the first distance if the positional shift of the hydrophone is detected, and to determine a second delay based on the time of the hydrophone relative to the second distance and the third distance respectively;

[0097] The sound field acquisition module 504 is used to perform delay compensation on the hydrophone in real time according to the first delay in the axial direction and the second delay in the radial direction, and to scan the transducer's line and surface volume to acquire the pulse sound field.

[0098] See details Figure 6 This is a schematic diagram of a pulse sound field acquisition system, illustrated in an exemplary embodiment of the present invention, and is described in detail below:

[0099] The hydrophone acts as a data acquisition card, sending the acquired pulsed sound field to the control terminal (including but not limited to a PC). The PC controls the driver source, and the electrical signal generated by the driver source is transmitted through an impedance network and converted into sound waves by a transducer. The impedance network adjusts the system impedance to ensure efficient sound wave transmission; the transducer converts the electrical signal into sound waves and ensures that the sound wave parameters match the system requirements. Therefore, the driver source, impedance network, and transducer cooperate to realize the function of the acoustic system.

[0100] On the PC, the offset distance of the hydrophone in three dimensions (X-axis, Y-axis, Z-axis) is determined in the three-dimensional system to calculate the corresponding delay. The three-dimensional motion control acquisition card performs real-time compensation according to the delay. That is, the acquisition card is triggered by the delay to obtain the pulse sound field, so as to ensure that the sound field information acquired at any position is at the same pulse time and has the same number of pulses, and to ensure that the acquired sound field information includes all sound source information, thus ensuring the accuracy of pulse sound field acquisition.

[0101] Based on the above embodiments, the pulse sound field acquisition system further includes:

[0102] A hydrophone that receives the ultrasonic signal from the transducer is suspended in the liquid perpendicular to the fluid-solid interface and located on the central axis of the transducer. This ensures that the hydrophone accurately receives the ultrasonic signal from the transducer.

[0103] The hydrophone is moved by a dual-axis lead screw slide controlled by a three-dimensional motion control module. The three-dimensional motion control module consists of three sets of identical devices, which respectively control the precise movement of the hydrophone in the X, Y and Z axes. Each set of devices is driven by a stepper motor to move the slide by a lead screw transmission.

[0104] Specifically, the three-dimensional motion control module consists of three sets of identical devices, which control the precise movement of the hydrophone in the X, Y, and Z axes respectively. This ensures that the hydrophone can accurately receive signals at different positions and angles. At the same time, the position can also be adjusted by controlling the dual-axis lead screw slide to reach the preset position.

[0105] It should be noted that the pulse sound field acquisition system and the pulse sound field acquisition method provided in the above embodiments belong to the same concept. The specific operation methods of each module and unit have been described in detail in the method embodiments and will not be repeated here. In practical applications, the pulse sound field acquisition system provided in the above embodiments can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. This is not a limitation here.

[0106] The above method determines, in real time, the first axial offset distance of the hydrophone based on the positional relationship between the transducer and the hydrophone, and the second and third radial distances corresponding to the nearest and farthest sound source points, respectively. A first axial delay of the hydrophone is determined based on the first distance, and a second delay is determined based on the time taken between the hydrophone and the second and third distances, respectively. Delay compensation is applied to the hydrophone in real time based on the first axial delay and the second radial delay, and the transducer's lines and surfaces are scanned to acquire pulse sound fields. This pulse sound field acquisition system avoids manual intervention, improving acquisition efficiency. Furthermore, by measuring the hydrophone's position relative to the transducer in real time, calculating the pulse arrival time at different positions, and adjusting the acquisition pulse delay accordingly, the system compensates for the acquisition trigger delay in real time. This ensures that sound field information acquired at any position has the same pulse time and the same number of pulses, and that the acquired sound field information includes all sound source information, thus ensuring high accuracy in pulse sound field acquisition.

[0107] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for acquiring pulsed sound fields, characterized in that, The method includes: Obtain the positional relationship between the transducer and the hydrophone; Based on the positional relationship between the transducer and the hydrophone, the first distance of the hydrophone offset in the axial direction is determined in real time, and the second and third distances in the radial direction are respectively to the nearest sound source point and the farthest sound source point. If a positional shift of the hydrophone is detected, the first axial delay of the hydrophone is determined based on the first distance, and the second delay is determined based on the time taken by the hydrophone at the second distance and the third distance, respectively. The hydrophone is compensated for delays in real time based on the first delay in the axial direction and the second delay in the radial direction, and the transducer is scanned to collect the pulse sound field.

2. The pulse sound field acquisition method according to claim 1, characterized in that, Before determining the positional relationship between the transducer and the hydrophone, it also includes Configure the transducer drive pulse to a preset number of cycles so that the hydrophone can collect pulses within the preset number of cycles.

3. The pulse sound field acquisition method according to claim 2, characterized in that, Based on the positional relationship between the transducer and the hydrophone, the first distance of axial offset of the hydrophone is determined in real time, including: Determine the vertical distance from the center acoustic axis of the hydrophone to the lowest point of the transducer, and the axial height from the surface of the transducer to the lowest point of the transducer; The vertical height of the hydrophone to the transducer surface is determined based on the vertical distance and axial height. The axial offset distance of the hydrophone is determined based on the vertical height. The first distance of the hydrophone in axial offset is determined based on the axial offset distance.

4. The pulse sound field acquisition method according to claim 3, characterized in that, Based on the positional relationship between the transducer and the hydrophone, the second and third distances corresponding to the nearest and farthest sound source points in the radial direction are determined in real time, including: Determine the first movement distance of the hydrophone in the X-axis direction and the second movement distance in the Y-axis direction in the radial dimension; The radial offset distance of the hydrophone is determined by performing a root operation on the sum of the squares of the first moving distance and the second moving distance; The second distance of the hydrophone to the nearest sound source is determined by taking the root of the sum of the squares of the vertical height based on the difference between the radius of the transducer and the radial offset distance. The third distance of the hydrophone from the farthest sound source point in the radial direction is determined by performing a root operation on the sum of the transducer's radius and the radial offset distance, and the sum of the squares of the vertical height.

5. The pulse sound field acquisition method according to claim 1, characterized in that, Determining a first axial delay of the hydrophone based on the first distance, and determining a second delay based on the time taken by the hydrophone at the second and third distances respectively, including: The first axial delay of the hydrophone is determined based on the first ratio of the first distance to the speed of sound. The pulse duration is determined based on the preset number of cycles of the transducer drive pulse and the current pulse frequency; Determine a second ratio of the second distance to the speed of sound and a third ratio of the third distance to the speed of sound; The second ratio, the third ratio, and the pulse duration are combined to form a delay compensation interval, and the second delay is determined based on the delay compensation interval.

6. The pulse sound field acquisition method according to claim 1, characterized in that, The hydrophone is compensated for delays in real time based on a first axial delay and a second radial delay, and the transducer's surface volume is scanned to acquire a pulse sound field, including: The hydrophone is compensated for delay in real time in the axial and radial directions according to the first delay and the second delay, respectively. The hydrophone is triggered by the delay so that the pulse sound field collected from pulses at different positions carries the same pulse time and the same number of pulses.

7. The pulse sound field acquisition method according to claim 2, characterized in that, Configure the transducer drive pulse to a preset number of cycles so that the hydrophone can acquire pulses within the preset number of cycles, including: Configure the transducer drive pulse to a preset cycle number of 20-50, so that the hydrophone can collect pulses in the second half of the preset cycle number.

8. The pulse sound field acquisition method according to any one of claims 1 to 7, characterized in that, After acquiring the pulse sound field, the process also includes: Based on the radial and axial sound pressure distribution of the pulsed sound field, sound field parameters are calculated, the performance parameters of the transducer's sound field characteristics are measured, and evaluation results are generated. The transducer is a focusing transducer, and the performance parameters of the focusing transducer's sound field include the major axis dimension of the focal region, the axial sub-maximum sound pressure and attenuation of the focal region, the width of the focal plane, the highest sidelobe sound pressure and attenuation, the focal region area, the focal region sound intensity distribution and corresponding sound power under the current excitation, and the symmetry of the sound field's focal plane.

9. A pulse sound field acquisition system, characterized in that, The system includes: The position determination module is used to obtain the positional relationship between the transducer and the hydrophone; The distance determination module determines, in real time, the first distance of the hydrophone offset in the axial direction, and the second and third distances in the radial direction to the nearest and farthest sound source points, respectively, based on the positional relationship between the transducer and the hydrophone. The delay determination module is used to determine a first delay of the hydrophone in the axial direction based on the first distance if the positional shift of the hydrophone is detected, and to determine a second delay based on the time of the hydrophone relative to the second distance and the third distance respectively; The sound field acquisition module is used to perform delay compensation on the hydrophone in real time according to the first delay in the axial direction and the second delay in the radial direction, and to scan the transducer's line and surface volume to acquire the pulse sound field.

10. The pulse sound field acquisition system according to claim 9, characterized in that, Also includes: A hydrophone that receives the ultrasonic signal from the transducer, the hydrophone being suspended in the liquid perpendicular to the fluid-solid interface and located on the central axis of the transducer; The hydrophone is moved by a dual-axis lead screw slide controlled by a three-dimensional motion control module. The three-dimensional motion control module consists of three sets of identical devices, which respectively control the precise movement of the hydrophone in the X, Y and Z axes. Each set of devices is driven by a stepper motor to move the slide by a lead screw transmission.

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