A non-contact detection system based on impact elastic waves

Abstract

The application provides a kind of non-contact detection system based on impact elastic wave, belong to civil engineering, building, road and bridge, hydraulic engineering quality safety detection technical field, including: laser vibration meter, excitation transmitter, high-pressure gas tank, steering base, excitation ball and detection host computer;The application uses laser vibration meter to remotely measure vibration signal, without contact, compared with the traditional acceleration sensor must be detected with the measured surface, avoid the acceleration sensor when pressing on the measured surface to the original vibration caused by inhibition or interference.The application compared with the acceleration sensor vibration measurement mode, without contact, especially for high altitude, climbing dead angle, high temperature surface, underwater and other acceleration sensor inconvenient contact test object, while effectively improving the test efficiency and range, also better guarantee the personal safety of operator.

Description

Technical Field

[0001] This invention relates to the field of quality and safety testing technology for civil engineering, architecture, roads and bridges, and water conservancy projects, and in particular to a non-contact testing system based on impact elastic waves. Background Technology

[0002] Non-destructive testing (NDT) is a rapidly developing emerging engineering science in recent years. It is defined as an inspection method that utilizes the phenomenon that changes in the physical properties of a substance due to defects or differences in its microstructure, without damaging its original state or chemical properties. This method aims to test, display, and evaluate these changes without compromising the performance or form of the inspected object, thereby understanding and evaluating the properties, state, or internal structure of materials, products, equipment components, etc. Impact elastic wave testing is an important NDT method.

[0003] Among the non-destructive testing techniques for various civil engineering projects, the impact elastic wave testing method is widely used. Whether it's the subgrade filling and pavement paving of highways and railways, or the construction and maintenance of bridges, tunnels, and other important structures, the impact elastic wave testing method can be seen everywhere.

[0004] Based on the principle of impact elastic waves, a metal hammer is typically used to strike the surface being tested, generating impact and vibration that induces impact elastic waves. An accelerometer attached to the surface then collects the vibration signal. By processing and analyzing the vibration signal, physical parameters such as the volume, thickness, strength, and defects of the test object can be obtained. Patent CN 109001300 A discloses a soundproofing device suitable for impact echo audio frequency detection. This patent discloses a non-contact detection method that indirectly collects vibrations from the tested surface using a microphone, adding a significant contribution to the field of non-destructive testing based on elastic waves. However, this method still requires personnel to press a soundproofing pad to adhere the microphone to the tested surface, thus isolating it from external noise interference.

[0005] Therefore, whether using traditional accelerometers or shock echo acoustic testing, the sensor and the surface being tested must always be in direct or indirect contact or contact. In other words, the area being tested must be accessible to the testing personnel or equipment. This significantly limits the testing efficiency and application range of the shock elastic wave testing method, and how to effectively improve testing efficiency and range is a problem that needs to be solved.

[0006] Therefore, there is an urgent need in this field for a technical solution that can effectively improve detection efficiency and detection range.

[0007] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0008] The purpose of this invention is to provide a technical solution that can effectively improve detection efficiency and detection range.

[0009] To achieve the above objectives, the present invention provides the following solution:

[0010] A non-contact detection system based on shock elastic waves, characterized in that it comprises: a laser vibrometer, a vibration transmitter, a high-pressure gas tank, a steering base, a vibration ball, and a detection host;

[0011] The detection laser transmission and reception path of the laser vibrometer is mounted on the rotating base parallel to the emission direction of the excitation transmitter, or the relative angle between the detection laser transmission and reception path of the laser vibrometer and the emission direction of the excitation transmitter can be changed, as long as the excitation ball emitted by the excitation transmitter can collide with the test object detected by the laser vibrometer; a high-pressure gas tank that provides emission power to the excitation transmitter is installed on the rotating base;

[0012] The excitation transmitter has a valve and a launching tube. The front end of the valve is connected to a high-pressure gas tank. The high-pressure gas in the high-pressure gas tank is released and closed by opening and closing the valve. The excitation ball is placed inside the launching tube of the excitation transmitter.

[0013] The laser vibration meter remotely detects vibration signals on the surface of the test object using a laser. The laser vibration meter is connected to the testing host.

[0014] Optionally, an object is launched remotely by an excitation transmitter to collide with the surface of the test object, generating vibration and forming an impact elastic wave. The vibration signal of the test object is collected remotely by a laser vibrometer, and the vibration signal is analyzed and processed by the detection host to achieve non-contact non-destructive testing of impact elastic waves.

[0015] Optionally, the excitation launcher uses compressed air to launch the excitation ball, or uses the energy generated by releasing the stored energy of the elastic material, electromagnetic conversion, and the explosive combustion of gunpowder as the launch power.

[0016] Optionally, the excitation ball may be a metal sphere, an ice ball or icicle made of water-absorbing material after freezing, or a projectile made of plastic, rubber, or clay; the excitation ball is only used as a kinetic energy carrier to collide with the test object and generate vibration signals, and its specific material and shape are not limited.

[0017] Optionally, the excitation emitter and the laser vibrometer can be used in pairs, or different numbers of excitation emitters or laser vibrometers can be used together to improve testing efficiency and accuracy.

[0018] Optionally, the detection host includes signal processing and analysis functions. The detection host can be independent of other components and connected via signal cables or wireless technology, or it can be integrated with other components to form a whole.

[0019] Optionally, during testing, an appropriate number of excitation balls need to be placed inside the excitation emitter beforehand. The steering base is adjusted so that the laser vibrometer and the emission port of the excitation emitter are aligned with the test object. By quickly opening and closing the valve located inside the excitation emitter, a portion of the high-pressure gas stored in the high-pressure gas tank can be released rapidly. The released high-pressure gas pushes an excitation ball pre-placed inside the excitation emitter along the emission tube. Under the action of inertia, the emitted excitation ball flies in the air along the direction of the emission tube and finally collides with the surface of the test object, thereby triggering an impact elastic wave. After the laser vibrometer remotely detects the test signal on the surface of the test object, it transmits the vibration signal to the detection host for analysis and processing.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. This invention uses a laser vibration meter to remotely measure vibration signals without contact. Compared with the traditional method of accelerometers that must be in contact with the surface being measured, this invention avoids the suppression or interference caused by the accelerometer pressing on the surface being measured.

[0022] 2. Compared with vibration measurement using accelerometers, this invention does not require contact, which is especially beneficial for test objects where accelerometers are inconvenient to access, such as those at high altitudes, in climbing blind spots, on high-temperature surfaces, or underwater. It effectively improves testing efficiency and range while also better protecting the personal safety of operators.

[0023] 3. The excitation transmitter used in this invention launches an excitation object for remote, airborne excitation. Compared with traditional contact excitation methods such as hand hammers and electromagnetic excitation to generate impact elastic waves, it has advantages such as high excitation efficiency, small excitation distance limitation, no secondary excitation, and low requirements for the operating skills of the excitation personnel. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments 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.

[0025] Figure 1 This is a schematic diagram of the system structure provided in an embodiment of the present invention.

[0026] 1-Laser vibration meter, 2-Vibration emitter, 3-High-pressure gas tank, 4-Swivel base, 5-Laser beam, 6-Vibration ball, 7-Test object, 8-Detection host. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The purpose of this invention is to provide a technical solution that can effectively improve detection efficiency and detection range.

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Example 1:

[0031] This embodiment provides a non-contact detection system based on shock elastic waves, such as... Figure 1 As shown, it includes: a laser vibrometer 1, a vibration transmitter 2, a high-pressure gas tank 3, a steering base 4, a vibration ball 6, and a detection host 8;

[0032] The detection laser transmission and reception path of the laser vibrometer 1 is parallel to the emission direction of the excitation transmitter 2 and mounted on the steering base 4. Alternatively, the relative angle between the detection laser transmission and reception path of the laser vibrometer 1 and the emission direction of the excitation transmitter 2 can be changed, as long as the excitation ball 6 emitted by the excitation transmitter 2 can collide with the test object 7 detected by the laser vibrometer 1. A high-pressure gas tank 3 is installed on the steering base 4 to provide emission power for the excitation transmitter 2.

[0033] The excitation emitter 2 has a valve and an emission tube. The front end of the valve is connected to the high-pressure gas tank 3. The high-pressure gas in the high-pressure gas tank 3 is released and closed by opening and closing the valve. The excitation ball 6 is placed inside the emission tube of the excitation emitter 2.

[0034] The laser vibration meter 1 remotely detects the vibration signal on the surface of the test object 7 via laser. The laser vibration meter 1 is connected to the detection host 8. The laser vibration meter 1 can remotely detect the vibration signal on the surface of the test object 7 via laser. The laser beam 5 is a schematic effect of the laser trajectory of the laser vibration meter 1 (not a real object). The test object 7 is an example model, but it can actually be any object surface.

[0035] In one embodiment, an object is launched remotely by the excitation emitter 2 and collided with the surface of the test object 7 to generate vibration and form an impact elastic wave. The vibration signal of the test object 7 is collected remotely by the laser vibration meter 1, and the vibration signal is analyzed and processed by the detection host 8 to achieve non-contact non-destructive testing of impact elastic waves.

[0036] In one embodiment, the excitation launcher 2 uses compressed air to launch the excitation ball 6, or uses the energy generated by releasing the stored energy of the elastic material, electromagnetic conversion, and the explosive combustion of gunpowder as the launch power. The ultimate goal of all these launch power methods is to launch the excitation ball 6 into the test object 7 from a distance, causing a collision; all can be considered embodiments of the present invention.

[0037] In one embodiment, the excitation ball 6 may be a metal sphere, an ice ball or icicle made of water-absorbing material after freezing, or a projectile made of plastic, rubber, or clay; the excitation ball 6 serves only as a kinetic energy carrier that collides with the test object 7 and generates vibration signals, and is not limited to specific materials and shapes.

[0038] In one embodiment, the excitation emitter 2 is used in pairs with the laser vibrometer 1, or different numbers of excitation emitters 2 or laser vibrometers 1 are used together to improve testing efficiency and accuracy.

[0039] In one embodiment, the detection host 8 includes signal processing and analysis functions. The detection host 8 can be independent of other components and connected via signal cables or wireless technology, or it can be integrated with other components to form a whole.

[0040] In one embodiment, during testing, an appropriate number of excitation balls 6 need to be placed inside the excitation emitter 2 beforehand, and the steering base 4 is adjusted so that the laser vibration meter 1 and the emission port of the excitation emitter 2 are aligned with the test object 7. By quickly opening and closing the valve located inside the excitation emitter 2, a portion of the high-pressure gas stored in the high-pressure gas tank 3 can be quickly released. The released high-pressure gas pushes an excitation ball 6, which is placed inside the excitation emitter 2, to be ejected along the emission tube. The ejected excitation ball 6 flies in the air along the direction of the emission tube under the action of inertia, and finally collides with the surface of the test object 7, thereby triggering an impact elastic wave. After the laser vibration meter 1 remotely detects the test signal on the surface of the test object 7, it transmits the vibration signal to the detection host 8 for analysis and processing.

[0041] In one embodiment, during actual testing, the system also requires a corresponding power supply and transport equipment. When the testing system is moved to the area to be tested, the excitation emitter and laser vibrometer are aligned with the test object by adjusting the steering base. The laser vibrometer has a built-in indicator laser beam, which can be used to confirm the orientation of the excitation emitter and laser vibrometer. The optimal effect is achieved when the distance between the excitation ball emitted by the excitation emitter and the detection focus of the laser vibrometer on the surface of the test object is about 10 centimeters.

[0042] The point of impact of the emitted excitation ball on the test object should be approximately 10 centimeters away from the spot of the laser beam indicating the test object's surface. The excitation ball can be emitted when the laser beam of the excitation tester is aligned with the test object's surface. Upon impact, the emitted excitation ball triggers vibration. The laser vibrometer then sends the detected vibration signal to the main testing unit for processing to obtain the required test parameters.

[0043] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0044] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A non-contact detection system based on impact elastic waves, characterized in that, include: Laser vibration meter (1), excitation transmitter (2), high-pressure gas tank (3), steering base (4), excitation ball (6) and detection host (8); The transmission and reception path of the detection laser of the laser vibrometer (1) is parallel to the emission direction of the excitation transmitter (2) and mounted on the steering base (4). Alternatively, the relative angle between the transmission and reception path of the detection laser of the laser vibrometer (1) and the emission direction of the excitation transmitter (2) can be changed, as long as the excitation ball (6) emitted by the excitation transmitter (2) can collide with the test object (7) detected by the laser vibrometer (1). A high-pressure gas tank (3) is installed on the steering base (4) to provide emission power for the excitation transmitter (2). The excitation emitter (2) has a valve and an emission tube. The front end of the valve is connected to the high-pressure gas tank (3). The high-pressure gas in the high-pressure gas tank (3) is released and closed by opening and closing the valve. The excitation ball (6) is placed inside the emission tube of the excitation emitter (2). The laser vibration meter (1) remotely detects the vibration signal on the surface of the test object (7) using laser. The laser vibration meter (1) is connected to the detection host (8). The object is launched remotely by the excitation emitter (2) and collided with the surface of the test object (7) to generate vibration and form an impact elastic wave. The vibration signal of the test object (7) is collected remotely by the laser vibration meter (1). The vibration signal is analyzed and processed by the detection host (8) to realize non-contact non-destructive testing of impact elastic waves.

2. The non-contact detection system based on impact elastic waves according to claim 1, characterized in that, The excitation launcher (2) uses compressed air to launch the excitation ball (6), or uses the energy generated by releasing the stored energy of the elastic material, electromagnetic conversion, and the explosive combustion of gunpowder as the launching power.

3. The non-contact detection system based on impact elastic waves according to claim 1, characterized in that, The excitation ball (6) is only used as a kinetic energy carrier to collide with the test object (7) and generate vibration signals, and its specific material and shape are not limited.

4. The non-contact detection system based on impact elastic waves according to claim 1, characterized in that, The excitation emitter (2) and the laser vibration meter (1) are used in pairs, or different numbers of excitation emitters (2) or laser vibration meters (1) are used together to improve testing efficiency and accuracy.

5. The non-contact detection system based on impact elastic waves according to claim 1, characterized in that, The detection host (8) includes signal processing and analysis functions. The detection host (8) can be independent of other components and can be connected through signal cables or wireless technology. It can also be integrated with other components to form a whole.

6. The non-contact detection system based on impact elastic waves according to claim 1, characterized in that, During testing, an appropriate number of excitation balls (6) need to be placed inside the excitation emitter (2) beforehand. Adjust the steering base (4) so ​​that the laser vibration meter (1) and the emission port of the excitation emitter (2) are aligned with the test object (7). By quickly opening and closing the valve located inside the excitation emitter (2), a portion of the high-pressure gas stored in the high-pressure gas tank (3) can be quickly released. The released high-pressure gas pushes an excitation ball (6) placed inside the excitation emitter (2) to be ejected along the emission tube. The ejected excitation ball (6) flies in the air along the direction of the emission tube under the action of inertia. Finally, it collides with the surface of the test object (7) to generate an impact elastic wave. After the laser vibration meter (1) detects the test signal on the surface of the test object (7) remotely, it transmits the vibration signal to the detection host (8) for analysis and processing.

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