Flexible ultrasonic array detection system for non-open interior cavities of composite structures

Abstract

The present application relates to the technical field of nondestructive testing, in particular to a flexible ultrasonic array detection system for non-open inner cavity of composite material structure. The flexible ultrasonic scanner is used to pull the flexible ultrasonic array transducer, so that the flexible ultrasonic array transducer moves in a linear direction for scanning, and then the signal of the array wafer of the flexible ultrasonic array transducer is transmitted to the ultrasonic array unit for processing. The ultrasonic automatic scanning detection of the non-open inner cavity of the composite material with different lengths is realized. The ultrasonic rapid automatic scanning detection of the inner reinforcing rib of the non-open inner cavity of the composite material structure can be completed at one time. The detection automation degree is high, the detection efficiency is high, the detection result can be recorded and visualized, the defect positioning is easy, the detection result is less affected by the technical state and subjective factors of the detector, and the detectability, detection efficiency and reliability of the inner reinforcing rib of the non-open inner cavity of the composite material structure are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of nondestructive testing technology, and in particular to a flexible ultrasonic array testing system for non-open cavities of composite material structures. Background Technology

[0002] Non-open cavities in composite material structures are a crucial structural form, demanding extremely high quality. To ensure the quality of these cavities, 100% non-destructive testing is required. Due to the confined space and elongated geometric characteristics of these cavities, current testing primarily employs ultrasonic reflection methods. To achieve comprehensive testing of the non-open cavities, ultrasonic scanning of inaccessible areas within the cavity is necessary.

[0003] Please refer to Figure 1 The current ultrasonic testing method is as follows: a manual scanning method is adopted. The ultrasonic transducer 2 is inserted through the scanning rod from the opening end of the non-open inner cavity 1 of the composite material structure. The ultrasonic transducer 2 is inserted through the scanning rod to realize the manual ultrasonic scanning test of the reinforcing ribs. The main shortcomings are: (1) the ultrasonic transducer 2 usually adopts a single crystal probe, which has low detection efficiency and high labor intensity; (2) it is difficult to accurately realize the coverage scan of the reinforcing ribs of the non-open inner cavity 1 of the composite material structure, which easily leads to missed detection; (3) the degree of automation of ultrasonic testing is low, and the test results are greatly affected by the technical status and subjective factors of the tester, which easily leads to missed detection; (4) the test results cannot be recorded and visualized, which affects the reliability of the test results; (5) it is difficult to detect and locate defects.

[0004] As an improvement, automated ultrasonic scanning inspection is employed. Currently, the commonly used ultrasonic inspection method involves a specialized scanning mechanism that allows the ultrasonic transducer 2 to extend into the non-open cavity 1 of the composite material structure to scan the reinforcing ribs. Its main drawback is:

[0005] (1) When the non-open inner cavity 1 of the composite material structure exceeds 1m or even reaches 20m, due to the geometric size limitation of the non-open inner cavity 1 of the composite material structure, the mechanical stiffness and strength of the scanning mechanism are difficult to guarantee the accurate ultrasonic automatic scanning detection and defect location requirements of the transducer for the internal reinforcing ribs of the non-open inner cavity 1 of the composite material structure, thus affecting the detection effect and the reliability of the detection results, and making it difficult to achieve reliable detection of the non-open inner cavity 1 of the composite material structure; (2) Low detection efficiency. Summary of the Invention

[0006] (1) Technical problems to be solved

[0007] This invention provides a flexible ultrasonic array detection system for non-open cavities of composite material structures, which solves the technical problems of low detectability, low detection efficiency, and low detection reliability of internal reinforcing ribs in non-open cavities of composite material structures.

[0008] (2) Technical solution

[0009] This invention provides a flexible ultrasonic array inspection system for non-open cavities of composite material structures, comprising: a flexible ultrasonic array transducer, a flexible ultrasonic scanner, and an ultrasonic array unit; the bottom of the flexible ultrasonic array transducer is provided with an array crystal for scanning the reinforcing ribs to be inspected within the non-open cavity of the composite material structure; the flexible ultrasonic scanner includes two sets respectively disposed at both ends of the non-open cavity of the composite material structure, and is connected to the front and rear flexible connection ends of the flexible ultrasonic array transducer respectively by flexible connecting lines, thereby traction of the flexible ultrasonic array transducer to move and scan in a straight line; the ultrasonic array unit is disposed outside the non-open cavity of the composite material structure and is connected to the array crystal through an ultrasonic signal connection end disposed on the flexible ultrasonic array transducer for processing the signals of the array crystal.

[0010] Furthermore, the flexible ultrasonic array transducer also includes a flexible rod and a guide wheel, one end of the flexible rod being connected to the top of the flexible ultrasonic array transducer, and the other end of the flexible rod being connected to the guide wheel.

[0011] Furthermore, the flexible rod includes a left flexible rod and a right flexible rod, which are symmetrically arranged on the top of the flexible ultrasonic array transducer and are respectively connected to the left guide wheel and the right guide wheel.

[0012] Furthermore, the external dimensions of the flexible ultrasonic array transducer satisfy the design formula: M = H ± K1; N = W ± K2; where M is the height of the flexible ultrasonic array transducer, N is the width of the flexible ultrasonic array transducer, H is the height of the reinforcing rib of the non-open inner cavity of the composite material structure under test, W is the width of the reinforcing rib of the non-open inner cavity of the composite material structure under test, K1 is the vertical mechanical coefficient, and K2 is the horizontal mechanical coefficient.

[0013] Furthermore, the flexible ultrasonic scanner includes a motor, a flexible base, and supports. The motor is mounted on the top of the flexible base, and a take-up shaft is connected to the motor shaft facing downwards. Supports are respectively provided at the four corners of the lower end of the flexible base. The height of the supports is adjustable. A cable outlet is provided on one side of the flexible base. One end of the flexible connecting cable is fixed to the take-up shaft, and the other end is connected to the front flexible connection end of the flexible ultrasonic array transducer through the cable outlet. The length of the flexible connecting cable matches the length of the non-open inner cavity of the composite material structure.

[0014] Furthermore, the motor includes an encoder and a rotation controller, the encoder being used to detect the rotation angle of the motor, and the rotation controller being used to control the rotation angle of the motor.

[0015] Furthermore, the ultrasonic array unit includes an ultrasonic array instrument host, a motor control connector, an encoder connector, and an ultrasonic array signal connector. The ultrasonic array instrument host is respectively provided with the motor control connector, the encoder connector, and the ultrasonic array signal connector. The motor control connector is electrically connected to the rotation controller, the encoder connector is electrically connected to the encoder, and the ultrasonic array signal connector is electrically connected to the ultrasonic signal connection terminal.

[0016] Furthermore, instrument supports are provided at the four corners of the lower end of the ultrasonic array instrument main unit, and the height of the instrument supports is adjustable.

[0017] Furthermore, it also includes a power supply, which consists of a rechargeable battery pack and provides operating power to the flexible ultrasonic array transducer, the flexible ultrasonic scanner, and the ultrasonic array unit.

[0018] Furthermore, it also includes support bases, with the non-open inner cavity of the composite material structure placed on two or more of the support bases to facilitate automatic ultrasonic scanning and detection.

[0019] (3) Beneficial effects

[0020] In summary, this invention uses a flexible ultrasonic scanner to pull a flexible ultrasonic array transducer, causing the transducer to move and scan along a straight line. The signals from the array wafers of the flexible ultrasonic array transducer are then transmitted to the ultrasonic array unit for processing. This enables automated ultrasonic scanning and inspection of non-open cavities of composite materials of varying lengths. A single scan can complete the rapid and automated ultrasonic scanning and inspection of the reinforcing ribs inside the non-open cavities of composite material structures. The inspection is highly automated, efficient, and less prone to missed detections. It is labor-intensive and environmentally friendly. The inspection results can be recorded and visualized, making defect location easy. The results are less affected by the operator's technical skill and subjective factors, thus significantly improving the inspectability, efficiency, and reliability of the reinforcing ribs inside the non-open cavities of composite material structures. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a composite material structure with a non-open internal cavity.

[0023] Figure 2 This is a schematic diagram of the connection relationship of a flexible ultrasonic array detection system for non-open cavities of composite material structures.

[0024] Figure 3 This is a schematic diagram of the structure of a flexible ultrasonic array transducer used in a flexible ultrasonic array detection system for non-open cavities of composite material structures.

[0025] Figure 4 This is a schematic diagram showing the connection between a flexible ultrasonic array transducer and a flexible ultrasonic scanner in a flexible ultrasonic array testing system for non-open cavities of composite material structures.

[0026] In the diagram: 1. Non-open internal cavity of composite material structure; 2. Ultrasonic transducer; 3. Flexible ultrasonic array transducer; 4. Flexible ultrasonic scanner; 5. Ultrasonic array unit; 30. Left flexible rod; 31. Right flexible rod; 32. Left guide wheel; 33. Right guide wheel; 40. Motor; 41. Flexible seat; 42. Support; 43. Rewinding shaft; 44. Flexible connecting line; 45. Encoder; 46. Rotation controller; 50. Instrument support; 6. Power supply; 7. Support base. Detailed Implementation

[0027] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present invention by way of example, but should not be used to limit the scope of the present invention. That is, the present invention is not limited to the described embodiments, and any modifications, substitutions and improvements to the parts, components and connection methods are covered without departing from the spirit of the present invention.

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] Please refer to Figures 2-4 The present invention provides a flexible ultrasonic array detection system for non-open cavities of composite material structures, comprising: a flexible ultrasonic array transducer 3, a flexible ultrasonic scanner 4, and an ultrasonic array unit 5.

[0030] The bottom of the flexible ultrasonic array transducer 3 is provided with an array of crystals for scanning the reinforcing ribs to be inspected within the non-open cavity 1 of the composite material structure. The array of crystals comprises n piezoelectric crystals, where n is calculated using the following formula:

[0031]

[0032] Where w is the width of the piezoelectric crystal, L is the side length of the reinforcing rib of the non-open inner cavity 1 of the composite material structure, and Δw is the spacing between two adjacent piezoelectric crystals. Since the array crystal consists of n piezoelectric crystals and covers the entire cross-section of the reinforcing rib of the non-open inner cavity 1 of the composite material structure being inspected, the probe does not need to scan along the cross-section of the reinforcing rib to achieve ultrasonic scanning of the entire reinforcing rib cross-section. Compared with a single-crystal probe, which requires scanning along the cross-section of the reinforcing rib, this significantly improves detection efficiency. The length of the piezoelectric crystal is 8–20 mm, and the width of the piezoelectric crystal is 0.8–3 mm. The thickness of the piezoelectric crystal is determined according to the required frequency, which is determined based on the thickness and material properties of the non-open inner cavity 1 of the composite material structure being inspected, as well as the defect detection requirements; generally, the frequency is selected between 5 and 10 MHz.

[0033] The flexible ultrasonic scanner 4 includes two sets respectively disposed at both ends of the non-open inner cavity 1 of the composite material structure, and is connected to the front flexible connection end and the rear flexible connection end of the flexible ultrasonic array transducer 3 respectively by a flexible connecting line 44. The flexible ultrasonic array transducer 3 is pulled, and the flexible ultrasonic scanner 4 can select to scan and detect the flexible ultrasonic array transducer 3 along one end of the non-open inner cavity 1 of the composite material structure, or it can select to scan and detect the flexible ultrasonic array transducer 3 along the other end of the non-open inner cavity 1 of the composite material structure, so that the flexible ultrasonic array transducer 3 moves and scans in a straight line.

[0034] The ultrasonic array unit 5 is disposed outside the non-open cavity 1 of the composite material structure and is connected to the array wafer via the ultrasonic signal connection terminal of the flexible ultrasonic array transducer 3 for processing the signal of the array wafer. The flexible ultrasonic array transducer 3 is pulled by the flexible ultrasonic scanner 4, causing it to move and scan in a straight line. The signal from the array wafer of the flexible ultrasonic array transducer 3 is then transmitted to the ultrasonic array unit 5 for processing. This enables automatic ultrasonic scanning and inspection of non-open cavities of composite materials of different lengths. A single scan can complete the rapid automatic ultrasonic scanning and inspection of the internal reinforcing ribs of the non-open cavity 1 of the composite material structure. The inspection is highly automated, efficient, and less prone to missed detections, requiring less labor and is environmentally friendly. The inspection results can be recorded and visualized, making defect location easy. The results are less affected by the inspector's technical condition and subjective factors, thus significantly improving the inspectability, efficiency, and reliability of the internal reinforcing ribs of the non-open cavity 1 of the composite material structure.

[0035] In some embodiments, the flexible ultrasonic array transducer 3 further includes a flexible rod and a guide wheel. One end of the flexible rod is connected to the top of the flexible ultrasonic array transducer 3, and the other end of the flexible rod is connected to the guide wheel. To achieve better contact between the array wafer and the surface of the reinforcing rib being tested, the flexible rod enables adaptive adjustment in the vertical direction. That is, the array wafer contacts the bottom of the non-open inner cavity 1 of the composite material structure, and the guide wheel at the other end of the flexible rod contacts the top of the non-open inner cavity 1 of the composite material structure, achieving a certain degree of tension. This ensures that during the scanning process, the array wafer remains in contact with the surface of the reinforcing rib being tested, forming a stable ultrasonic wave transmission and reception state.

[0036] Furthermore, the flexible rod includes a left flexible rod 30 and a right flexible rod 31. The flexible rod can be a telescopic rod with a spring installed. The left flexible rod 30 and the right flexible rod 31 are symmetrically arranged on the top of the flexible ultrasonic array transducer 3 and are respectively connected to the left guide wheel 32 and the right guide wheel 33, so that the force on both sides is more balanced during movement. At the same time, the guide wheels can reduce the dynamic friction force generated by contact, thereby facilitating the movement of the flexible ultrasonic array transducer 3.

[0037] In some embodiments, the external dimensions of the flexible ultrasonic array transducer 3 satisfy the design formulas: M = H ± K1; N = W ± K2; where M is the height of the flexible ultrasonic array transducer 3, N is the width of the flexible ultrasonic array transducer 3, H is the height of the reinforcing rib of the non-open inner cavity 1 of the composite material structure under test, W is the width of the reinforcing rib of the non-open inner cavity of the composite material structure under test, K1 is the vertical mechanical coefficient, and K2 is the horizontal mechanical coefficient. This ensures a suitable size, facilitating the placement of the flexible ultrasonic array transducer 3 into the non-open inner cavity 1 of the composite material structure, while also ensuring good stability.

[0038] In some embodiments, the flexible ultrasonic scanner 4 includes a motor 40, a flexible base 41, and supports 42. The motor 40 is mounted on the top of the flexible base 41, and a winding shaft 43 is connected downwards to the shaft of the motor 40. Supports 42 are respectively located at the four corners of the lower end of the flexible base 41. The height of the supports 42 is adjustable. A cable outlet is provided on one side of the flexible base 41. One end of the flexible connecting cable 44 is fixed to the winding shaft 43, and the other end is connected to the front flexible connection end of the flexible ultrasonic array transducer 3 through the cable outlet. The length of the flexible connecting cable 44 matches the length of the non-open inner cavity 1 of the composite material structure. The rotation of the motor 40 drives the winding shaft 43 to wind the flexible connecting cable 44, thereby pulling the flexible ultrasonic array transducer 3 closer to the flexible ultrasonic scanner 4, thus realizing the moving scanning of the flexible ultrasonic array transducer 3.

[0039] In some embodiments, the motor 40 includes an encoder 45 and a rotation controller 46. The encoder 45 is used to detect the rotation angle of the motor 40, and the rotation controller 46 is used to control the rotation angle of the motor 40. The combined use of the encoder 45 and the rotation controller 46 achieves closed-loop control of the motor 40, thereby accurately controlling the movement distance of the flexible ultrasonic array transducer 3.

[0040] In some embodiments, the ultrasonic array unit 5 includes an ultrasonic array instrument host, a motor 40 control connector, an encoder 45 connector, and an ultrasonic array signal connector. The ultrasonic array instrument host is equipped with the motor 40 control connector, the encoder 45 connector, and the ultrasonic array signal connector. The motor 40 control connector is electrically connected to the rotation controller 46, the encoder 45 connector is electrically connected to the encoder 45, and the ultrasonic array signal connector is electrically connected to the ultrasonic signal connection terminal. The ultrasonic array instrument host controls the movement of the flexible ultrasonic array transducer 3 and performs ultrasonic array signal transmission / reception, detection, and image display on the flexible ultrasonic array transducer 3.

[0041] In some embodiments, instrument supports 50 are respectively provided at the four corners of the lower end of the ultrasonic array instrument host. The height of the instrument supports 50 is adjustable, so that the ultrasonic array instrument host can adapt to the needs of various sites and obtain a stable operating environment.

[0042] In some embodiments, a power supply 6 is also included, which is composed of a rechargeable battery pack and provides working power 6 for the flexible ultrasonic array transducer 3, the flexible ultrasonic scanner 4 and the ultrasonic array unit 5, adapting to the needs of various sites and having good flexibility.

[0043] In some embodiments, a support base 7 is also included, on which the non-open inner cavity 1 of the composite material structure is placed. The support base 7 can conveniently fix the non-open inner cavity 1 of the composite material structure and level it to facilitate ultrasonic automatic scanning and detection.

[0044] Example:

[0045] Flexible ultrasonic array transducers 3 with n=32, 64, and 128 were selected. The length of each crystal was 8, 10, and 20 mm, and the width Δw of each crystal was 0.8, 1, and 2 mm, respectively. The frequencies were 5 MHz and 7.5 MHz. A series of flexible ultrasonic array scanning tests were carried out on the internal reinforcing ribs of non-open inner cavities 1 of composite material structures with lengths of 1 m, 3 m, 5 m, and 15 m. The test results show that the present invention can effectively perform ultrasonic coverage scanning tests on the non-open inner cavities 1 of the composite material structures under test, achieving the expected rapid ultrasonic scanning effect.

[0046] It should be noted that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. The present invention is not limited to the specific steps and structures described above and shown in the figures. Furthermore, for the sake of brevity, detailed descriptions of known methods and techniques are omitted here.

[0047] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art without departing from the scope of the invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this application should be included within the scope of the claims of this application.

Claims

1. A flexible ultrasonic array inspection system for non-opened interior cavities of composite structures, characterized by, The application relates to a flexible ultrasonic array transducer, a flexible ultrasonic scanner and an ultrasonic array unit. The bottom of the flexible ultrasonic array transducer is provided with an array wafer for scanning a detected reinforcing rib in a non-open inner cavity of a composite structure; The flexible ultrasonic scanner comprises two groups arranged at two ends of the non-open inner cavity of the composite structure respectively, and the front flexible connecting end and the rear flexible connecting end of the flexible ultrasonic array transducer are connected by flexible connecting lines respectively, so that the flexible ultrasonic array transducer is pulled to move and scan in a straight line direction; The ultrasonic array unit is arranged outside the non-open inner cavity of the composite structure, and the array wafer is connected with the ultrasonic signal connecting end of the flexible ultrasonic array transducer to process signals of the array wafer; The flexible ultrasonic array transducer further comprises a flexible rod and a guide wheel, one end of the flexible rod is connected with the top of the flexible ultrasonic array transducer, and the other end of the flexible rod is connected with the guide wheel; the flexible rod comprises a left flexible rod and a right flexible rod which are symmetrically arranged at the top of the flexible ultrasonic array transducer and connected with left and right guide wheels respectively. The size of the flexible ultrasonic array transducer satisfies a design formula:

2. A flexible ultrasonic array inspection system for non-opened cavities of composite structures according to claim 1, characterized in that, M=H+K1 N=W+K2 Wherein, M is the height of the flexible ultrasonic array transducer, N is the width of the flexible ultrasonic array transducer, H is the height of a reinforcing rib in a non-open inner cavity of a detected composite structure, W is the width of the reinforcing rib in the non-open inner cavity of the detected composite structure, K1 is a vertical mechanical coefficient, and K2 is a horizontal mechanical coefficient. The flexible ultrasonic scanner comprises a motor, a flexible seat and a support, the motor is arranged at the top end of the flexible seat, the rotating shaft of the motor is connected with a winding shaft downward, four corners of the lower end of the flexible seat are respectively provided with the supports, the height of the support is adjustable, one side of the flexible seat is provided with a wire outlet, one end of the flexible connecting line is fixed on the winding shaft, the other end is connected with the front flexible connecting end of the flexible ultrasonic array transducer through the wire outlet, and the length of the flexible connecting line matches the length of the non-open inner cavity of the composite structure.

3. A flexible ultrasonic array detection system for non-open interior cavities of composite structures according to claim 1, characterized in that, The motor comprises an encoder and a rotation controller, the encoder is used to detect the rotation angle of the motor, and the rotation controller is used to control the rotation angle of the motor.

4. A flexible ultrasonic array inspection system for non-opened cavities of composite structures according to claim 3, wherein, The ultrasonic array unit comprises an ultrasonic array instrument host, a motor control connecting seat, an encoder connecting seat and an ultrasonic array signal connecting seat, the motor control connecting seat, the encoder connecting seat and the ultrasonic array signal connecting seat are arranged on the ultrasonic array instrument host respectively, the motor control connecting seat is electrically connected with the rotation controller, the encoder connecting seat is electrically connected with the encoder, and the ultrasonic array signal connecting seat is electrically connected with the ultrasonic signal connecting end.

5. A flexible ultrasonic array inspection system for non-opened cavities of composite structures according to claim 4, wherein, Four corners of the lower end of the ultrasonic array instrument host are respectively provided with instrument supports, and the height of the instrument support is adjustable.

6. A flexible ultrasonic array inspection system for non-opened cavities of composite structures according to claim 5, wherein, ​ 7. The flexible ultrasonic array detection system for non-open interior cavities of composite structures of claim 1, wherein, The power supply is composed of rechargeable batteries and provides working power for the flexible ultrasonic array transducer, the flexible ultrasonic scanner and the ultrasonic array unit.

8. A flexible ultrasonic array detection system for non-opened cavities of composite structures according to any one of claims 1 to 7, characterized in that, The support seats are used to place the non-open inner cavity of the composite material structure on two or more support seats to facilitate the automatic ultrasonic scanning detection.

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