Method and device for automatically measuring sound field of air-coupled annular array ultrasonic transducer
The automated sound field measurement method using an air-coupled ring array ultrasonic transducer solves the problems of limited detection capability and low efficiency of air-coupled array ultrasonic testing technology in the inspection of aerospace composite materials, and realizes efficient and accurate sound field measurement and defect identification.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-30
- Publication Date
- 2026-03-31
AI Technical Summary
Existing air-coupled array ultrasonic testing technology suffers from limitations in detection capability and efficiency in the testing of aerospace composite materials, and lacks effective parameter optimization design and ultrasonic beam focusing control theory.
An automated sound field measurement method using an air-coupled ring array ultrasonic transducer is adopted. By fixing the transducer and photoacoustic sensor, controlling the excitation signal and scanning along the bow-shaped trajectory, the sound pressure distribution map is obtained, achieving efficient and accurate sound field measurement.
This improved the detection resolution and defect identification accuracy of the air-coupled ring array ultrasonic transducer, thereby enhancing detection efficiency and imaging intuitiveness.
Smart Images
Figure CN121762016A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of ultrasonic testing technology, and in particular to an automated method and apparatus for measuring the sound field of an air-coupled ring array ultrasonic transducer. Background Technology
[0002] With the continuous development of ultrasonic technology, the application of ultrasonic transducers in fields such as medical diagnosis, industrial non-destructive testing, and structural health monitoring is becoming increasingly widespread. Among them, air-coupled ultrasonic transducers, with their unique advantage of non-contact measurement, demonstrate significant value in special working conditions.
[0003] In the field of aerospace composite material testing, traditional water immersion / spray ultrasonic testing is widely used, but its limitations stem from factors such as component material properties, complex structures, and service environments, necessitating the use of air-coupled ultrasonic testing methods. However, existing single-channel air-coupled ultrasonic testing only supports the penetration method, resulting in limited testing capabilities and low efficiency. In contrast, air-coupled array ultrasonic testing technology combines the advantages of non-contact testing with the strong testing capabilities, high efficiency, and intuitive imaging of array ultrasonic technology, making it an important direction for overcoming the technological limitations in this field.
[0004] In air-coupled array ultrasonic testing technology, the complexity of the focused acoustic beam control mechanism and the diversity of defect response patterns still present some challenges when applied to the quality inspection of aerospace composite materials. These challenges include insufficient parameter optimization design methods for air-coupled array ultrasonic transducers and a relative lack of research on ultrasonic beam focusing control theory. It is important to emphasize that the transducer's spatial acoustic field performance (such as sound pressure distribution and focusing characteristics) directly determines the detection resolution and defect identification accuracy, and is a core indicator for evaluating its overall performance. Summary of the Invention
[0005] The purpose of this invention is to provide an automated method and apparatus for measuring the acoustic field of an air-coupled ring array ultrasonic transducer, which can conveniently realize the automatic measurement of the acoustic field characteristics of the air-coupled ring array ultrasonic transducer.
[0006] To achieve the above objectives, the present invention provides an automated method for measuring the sound field of an air-coupled ring array ultrasonic transducer, comprising the following steps: Step A1: Fix the air-coupled ring array ultrasonic transducer to the end of the transmitter clamping mechanism; Step A2: Fix the photoacoustic sensor to the end of the receiver clamping mechanism; Step A3: Control the air-coupled array ultrasonic detector to excite the air-coupled ring array ultrasonic transducer to emit pulse signals; Step A4: Control the receiving end clamping mechanism to carry the photoacoustic sensor and scan in a bow-shaped trajectory in the plane where the axis of the air-coupled ring array ultrasonic transducer is located to obtain pulse sound field signals at different positions in space; Step A5: Process the pulse sound field signal to obtain the sound pressure amplitude distribution; Step A6: Generate a sound pressure distribution map of the sound field based on the sound pressure amplitude distribution.
[0007] Preferably, the axis of the air-coupled ring array ultrasonic transducer coincides with the axis of the transmitter clamping mechanism.
[0008] Preferably, the axial direction of the photoacoustic sensor is perpendicular to the movement direction of the receiving end clamping mechanism.
[0009] Preferably, when controlling the air-coupled array ultrasonic detector, the delay rule is determined by calculating the difference between the propagation time of each array element to the focal point and the maximum propagation time.
[0010] Preferably, step A4 includes the following steps: Step A41: Set the starting point, ending point, scanning interval, step distance, and scanning length of the bow-shaped trajectory; Step A42: Control the receiving end clamping mechanism to carry the photoacoustic sensor and scan along the Y direction; Step A43: After reaching the preset scanning length, move along the Z direction to the preset scanning interval position, and at the new Z position, scan again along the Y direction; Step A44: Determine whether the scanning of the entire sound field plane is complete. If yes, proceed to step A45; otherwise, jump to step A42. Step A45: Obtain overall sound field signal data.
[0011] The present invention also provides an automated measurement device for the sound field of an air-coupled ring array ultrasonic transducer, comprising: The transmitter clamping mechanism secures the air-coupled ring array ultrasonic transducer and keeps its axis stable. The receiving end clamping mechanism has a photoacoustic sensor installed at its end, which drives the sensor to perform sound field measurement. An air-coupled ring array ultrasonic transducer, with a ring array structure and each array element having an equal area, is used to transmit ultrasonic signals and excite the formation of an air-coupled sound field. The photoacoustic sensor system includes: a photoacoustic sensor and a signal demodulator; The control mechanism, connected to the clamping mechanism, the air-coupled ring array ultrasonic transducer, and the photoacoustic sensor, performs the following operations: The control receiver clamping mechanism scans along a bow-shaped trajectory; Control the air-coupled ring array ultrasonic transducer to emit ultrasonic waves; Acquire and process the photoacoustic sensor signals to generate a sound pressure distribution map.
[0012] Preferably, the photoacoustic sensor system includes: a photoacoustic sensor and a signal demodulator; Photoacoustic sensors utilize the phase change of light caused by sound waves to achieve high-precision sound pressure detection, and convert nanoscale displacement into light intensity signals through optical interference; A signal demodulator is used to demodulate optical interference signals and convert them into electrical signals.
[0013] Therefore, the present invention employs the above-mentioned automated measurement method and apparatus for the acoustic field of an air-coupled ring array ultrasonic transducer, which has the following advantages: the automated measurement method and apparatus of the present invention can efficiently and accurately measure the acoustic field of the air-coupled ring array ultrasonic transducer, effectively improving the accuracy of the spatial acoustic field characteristic analysis of the air-coupled ring array ultrasonic transducer, and is of great significance for the performance characterization of the air-coupled ring array ultrasonic transducer. Attached Figure Description
[0014] Figure 1 This is a flowchart of the automated sound field measurement method for an air-coupled ring array ultrasonic transducer according to the present invention; Figure 2 This is a flowchart of step A4 in the automated measurement method of the acoustic field of an air-coupled ring array ultrasonic transducer of the present invention; Figure 3 This is a schematic diagram of a bow-shaped trajectory scan. Figure 4 The sound field measurement results of an air-coupled ring array ultrasonic transducer; Figure 5 The results are axial sound pressure measurements of an air-coupled ring array ultrasonic transducer. Figure 6 The radial sound pressure measurement results are for an air-coupled ring array ultrasonic transducer. Figure 7 This is a schematic diagram of the layout of the automated sound field measurement device for the air-coupled ring array ultrasonic transducer of the present invention. Figure 8 This is a schematic diagram of the transmitter clamping mechanism; Figure 9 This is a schematic diagram of the receiving end clamping mechanism.
[0015] Figure Labels 1. Control mechanism; 2. Air-coupled ring array ultrasonic transducer; 3. Photoacoustic sensor; 4. Air-coupled array ultrasonic detector; 5. Signal demodulator; 6. Motion control card; 7. Industrial control computer; 8. XY plane rotary slide one; 9. XZ plane rotary slide one; 10. Air-coupled ring array ultrasonic transducer fixture; 11. Photoacoustic sensor fixture; 12. XY plane rotary slide two; 13. XZ plane rotary slide two. Detailed Implementation
[0016] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.
[0017] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.
[0018] Example 1 like Figure 1 As shown, the automated measurement method for the acoustic field of an air-coupled ring array ultrasonic transducer includes the following steps: Step A1: Fix the air-coupled ring array ultrasonic transducer to the end of the transmitter clamping mechanism, with the axis of the air-coupled ring array ultrasonic transducer coinciding with the axis of the transmitter clamping mechanism; Step A2: Fix the photoacoustic sensor to the end of the receiving end clamping mechanism, with the axial direction of the photoacoustic sensor perpendicular to the movement direction of the receiving end clamping mechanism; Step A3: Control the air-coupled array ultrasonic detector to excite the air-coupled ring array ultrasonic transducer to emit pulse signals; When controlling an air-coupled array ultrasonic detector, a delay rule is determined by calculating the difference between the propagation time of each array element to the focal point and the maximum propagation time. This delay rule is then used to control the excitation delay of the array elements, ensuring that the sound beam emitted by each element is focused along the transducer axis. The expression for the delay focusing rule of each array element is as follows: ; in, This indicates the delay excitation time of each array element. Indicates the maximum propagation time. This indicates the propagation time of the array element-excited sound beam.
[0019] The expression is as follows: ; in, Indicates depth of focus. Indicates the outer diameter of the array element. Indicates the inner diameter of the array element. Indicates the speed of sound in air; Step A4: Control the receiving end clamping mechanism to carry the photoacoustic sensor in a bow-shaped configuration within the plane containing the axis of the air-coupled ring array ultrasonic transducer. Figure 3 Trajectory scanning acquires pulse sound field signals at different locations in space, such as... Figure 2 As shown, the specific steps include: Step A41: Set the starting point, ending point, scanning interval, step distance, and scanning length of the bow-shaped trajectory; Step A42: Control the receiving end clamping mechanism to carry the photoacoustic sensor and scan along the Y direction; Step A43: After reaching the preset scanning length, move along the Z direction to the preset scanning interval position, and at the new Z position, scan again along the Y direction; Step A44: Determine whether the scanning of the entire sound field plane is complete. If yes, proceed to step A45; otherwise, jump to step A42. Step A45: Obtain overall sound field signal data.
[0020] Step A5: Process the pulse sound field signal to obtain the sound pressure amplitude distribution; Step A6: Generate a sound pressure distribution map of the sound field based on the sound pressure amplitude distribution.
[0021] Based on the above-mentioned sound field measurement method for air-coupled ring array ultrasonic transducers, a sound field measurement experiment was conducted on an air-coupled ring array ultrasonic transducer with a frequency of 400kHz and a number of array elements of 3.
[0022] The parameters used in the sound field measurement experiment were as follows: the scanning interval and step distance were both 0.2 mm, the scanning speed was 10 mm / s, the focusing depth was 30 mm, and the excitation delays of each array element were 0 ns, 900 ns, and 1800 ns, respectively.
[0023] The experimental results of sound field measurement are as follows Figures 4-6 As shown.
[0024] Figure 4 This is the acoustic field diagram of an air-coupled ring array ultrasonic transducer, reflecting the distribution of sound pressure levels in space.
[0025] Figure 5 The curve represents the normalized axial sound pressure measurement result of the air-coupled ring array ultrasonic transducer. This curve intuitively reflects the focusing characteristics and energy distribution features of the air-coupled ring array ultrasonic transducer in the axial direction. The peak value of the curve can be used to characterize the penetration capability of the ultrasonic waves excited by the air-coupled ring array ultrasonic transducer through the test sample.
[0026] Figure 6This is the normalized radial sound pressure measurement result of the air-coupled ring array ultrasonic transducer. The curve intuitively reflects the width of the focused sound beam in the radial direction of the air-coupled ring array ultrasonic transducer. This index can be used to evaluate the lateral resolution capability of the air-coupled ring array ultrasonic transducer for defect detection.
[0027] Example 2 like Figure 7 As shown, the present invention also provides an automated measurement device for the sound field of an air-coupled ring array ultrasonic transducer, comprising: transmitter clamping mechanism such as Figure 8 As shown, a clamping mechanism is used to fix the air-coupled ring array ultrasonic transducer to ensure its stability during measurement. The transmitter clamping mechanism mainly includes: an XY plane rotary slide 8, which allows for horizontal (XY plane) rotation adjustment to adjust the angle of the air-coupled ring array ultrasonic transducer on the horizontal plane, ensuring the accuracy of its axial direction; an XZ plane rotary slide 9, which allows for rotation within the XZ plane, enabling fine-tuning of the transducer's angle in the vertical plane, further ensuring the coincidence of the transducer's axis with the transmitter clamping mechanism's axis; and an air-coupled ring array ultrasonic transducer clamp 10, used to fix the air-coupled ring array ultrasonic transducer. The stable clamping of the clamp ensures the transducer remains stable during measurement, preventing factors such as shaking from affecting the accuracy of the measurement results.
[0028] Receiver clamping mechanism such as Figure 9 As shown, a photoacoustic sensor is installed at the end, driving it to perform sound field measurements. The receiving end clamping mechanism mainly includes: a photoacoustic sensor clamp 11, used to fix the photoacoustic sensor and ensure its stable position during measurement, enabling it to accurately receive pulse sound field signals from different positions; an XY plane rotary slide 12, which can rotate in the XY plane to adjust the angle of the photoacoustic sensor on the horizontal plane, ensuring that the axis of the photoacoustic sensor is perpendicular to the movement direction of the receiving end clamping mechanism to meet measurement requirements; and an XZ plane rotary slide 13, which can rotate and adjust the angle of the photoacoustic sensor in the vertical plane, further ensuring that the installation position and orientation of the photoacoustic sensor meet measurement requirements, enabling it to accurately acquire pulse sound field signals from different spatial positions.
[0029] Air-coupled ring array ultrasonic transducer 2, with a ring array structure and each array element having an equal area, is used to transmit ultrasonic signals and excite the formation of an air-coupled sound field; The photoacoustic sensor system includes: a photoacoustic sensor 3 and a signal demodulator 5; The photoacoustic sensor 3 utilizes the phase change of light caused by sound waves to achieve high-precision sound pressure detection, and converts nanoscale displacement into light intensity signals through optical interference.
[0030] Signal demodulator 5 is used to demodulate optical interference signals and convert them into electrical signals.
[0031] Control mechanism 1 is connected to clamping mechanisms (transmitter clamping mechanism and receiver clamping mechanism), air-coupled ring array ultrasonic transducer 2 and photoacoustic sensor 3 respectively, and performs the following operations: The control receiver clamping mechanism scans along a bow-shaped trajectory; The motion control card 6 is connected to the control mechanism 1 and drives the receiving end clamping mechanism to perform scanning motion. The air-coupled array ultrasonic detector 4 excites the air-coupled ring array ultrasonic transducer 2 to emit pulse signals and collect sound field data; The industrial control computer 7 processes the sound field data and displays the sound pressure distribution results of the air-coupled ring array ultrasonic transducer 2.
[0032] It is worth noting that all contents not described in detail in this invention are existing technologies and are well known to those skilled in the art.
[0033] Therefore, the present invention employs the above-mentioned automated measurement method and apparatus for the acoustic field of an air-coupled ring array ultrasonic transducer, which can conveniently realize the automatic measurement of the acoustic field characteristics of the air-coupled ring array ultrasonic transducer.
[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.
Claims
1. A method for automated measurement of the acoustic field of an air-coupled annular array ultrasonic transducer, characterized by, The method comprises the following steps: Step A1, fixing the air-coupled annular array ultrasonic transducer to the end of the transmitting end clamping mechanism; Step A2, fixing the photoacoustic sensor to the end of the receiving end clamping mechanism; Step A3, controlling the air-coupled array ultrasonic detector to excite the air-coupled annular array ultrasonic transducer to emit a pulse signal; Step A4, controlling the receiving end clamping mechanism to carry the photoacoustic sensor to scan along an arch-shaped track in the plane where the axis of the air-coupled annular array ultrasonic transducer is located, and obtaining pulse sound field signals at different positions in space; Step A5, processing the pulse sound field signals to obtain the sound pressure amplitude distribution; Step A6, generating a sound pressure distribution map of the sound field based on the sound pressure amplitude distribution.
2. The air-coupled annular array ultrasonic transducer sound field automated measurement method of claim 1, wherein, The axis of the air-coupled annular array ultrasonic transducer coincides with the axis of the transmitting end clamping mechanism.
3. The air-coupled annular array ultrasonic transducer sound field automated measurement method of claim 1, wherein, The axis direction of the photoacoustic sensor is perpendicular to the movement direction of the receiving end clamping mechanism.
4. The air-coupled annular array ultrasonic transducer sound field automated measurement method of claim 1, wherein, When controlling the air-coupled array ultrasonic detector, the difference between the propagation time of each array element to the focal point and the maximum propagation time is calculated to determine the delay rule.
5. The air-coupled annular array ultrasonic transducer sound field automated measurement method of claim 1, wherein, Step A4 comprises the following steps: Step A41, setting the starting point, ending point, scanning interval, step distance and scanning length of the arch-shaped track; Step A42, controlling the receiving end clamping mechanism to carry the photoacoustic sensor to scan along the Y direction; Step A43, after reaching the preset scanning length, moving to the preset scanning interval position along the Z direction, and then scanning along the Y direction again at the new Z position; Step A44, judging whether the scanning of the entire sound field plane is completed, if yes, executing step A45, if not, jumping to step A42; Step A45, obtaining the overall sound field signal data.
6. An apparatus for automated measurement of the acoustic field of an air-coupled annular array ultrasonic transducer, characterized in that, It comprises: a transmitting end clamping mechanism for fixing the air-coupled annular array ultrasonic transducer and keeping its axis stable; a receiving end clamping mechanism for installing a photoacoustic sensor at the end and driving it to measure the sound field; an air-coupled annular array ultrasonic transducer in a ring array structure, each array element having an equal area, for emitting ultrasonic wave signals to excite the formation of an air-coupled sound field; a photoacoustic sensor system comprising a photoacoustic sensor and a signal demodulator; a control mechanism connected to the clamping mechanisms, the air-coupled annular array ultrasonic transducer and the photoacoustic sensor, for performing the following operations: controlling the receiving end clamping mechanism to scan along an arch-shaped track; controlling the air-coupled annular array ultrasonic transducer to emit ultrasonic waves; collecting and processing the photoacoustic sensor signals to generate a sound pressure distribution map.
7. The air-coupled annular array ultrasonic transducer sound field automated measurement apparatus of claim 6, wherein, The photoacoustic sensor system comprises a photoacoustic sensor and a signal demodulator. The photoacoustic sensor utilizes the phase change of light caused by sound waves to achieve high-precision sound pressure detection, and converts nanoscale displacement into light intensity signals through optical interference; The signal demodulator is used for demodulating the optical interference signals and converting them into electrical signals.