An automated rapid detection system for acoustic impedance tubes

Abstract

The present invention relates to an automated acoustic impedance tube rapid detection system, which comprises five parts: a sample picking and installation module, an integrated sound source and automated sound absorption test module, an automated sound insulation test module, a data acquisition and analysis module, and a bottom plate and control drive module. Compared with the prior art, the present invention takes the sound absorption and insulation standard samples as the detection objects, clamps the samples through the sample picking and installation module and installs them on the sample positioning section, realizes the sound absorption and sound insulation test requirements by adopting different impedance tube combination methods and data post-processing methods, and meets the automated rapid detection of a large number of sound absorption and insulation standard samples through the process-based coordinated operation among various modules, accurately obtaining the acoustic properties of the materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of testing the sound absorption and insulation performance of acoustic materials, and relates to an automated rapid detection system for acoustic impedance tubes. Background Art

[0002] With the rapid development of modern technology, the problem of noise pollution has become increasingly serious. Compared with air pollution and water pollution, etc., the harm of noise pollution to the human body is more easily ignored. Noise pollution can cause chronic and persistent damage to the human psychology and physiology. The main ways of noise control include source control, sound propagation path control, and receiver control. Using acoustic materials to absorb or isolate noise in the propagation path can effectively reduce noise pollution and achieve the purpose of noise reduction. The specific acoustic impedance rate, sound absorption coefficient, etc. of acoustic materials are important parameters for evaluating the sound absorption performance of materials, and the transmission coefficient and sound transmission loss, etc. are important parameters for evaluating the sound insulation performance of materials. Obtaining these parameters through testing to understand the sound absorption and insulation performance of materials is of great significance for the research on material noise reduction.

[0003] The methods for measuring the sound absorption and insulation performance of acoustic materials in the laboratory mainly include the reverberation room method and the impedance tube method. The reverberation room method is mostly used for testing the sound absorption and insulation performance of large structural components. Since the sound field in the reverberation room is a diffuse sound field, using the reverberation room method to measure the sound absorption coefficient and sound transmission loss of materials is closer to the sound absorption and insulation performance of materials in the actual use process; however, the reverberation room method has high requirements for test conditions and high test costs, and is not suitable for mass material-level performance testing in the product development stage. The impedance tube method generally calculates the sound absorption coefficient of materials through the standing wave ratio method or the transfer function method, and calculates the sound transmission loss of materials through the transfer function method. The test operation is simple and the cost is low; however, it is difficult to improve the test efficiency and test accuracy. Summary of the Invention

[0004] The purpose of the present invention is to provide an automated rapid detection system for acoustic impedance tubes.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] An automated rapid detection system for acoustic impedance tubes, comprising:

[0007] An integrated sound source, which is used to provide a stable and adjustable sound pressure signal;

[0008] A sound absorption test module, which includes a vibration isolation support for the sound absorption section, an impedance tube sound absorption section installed on the vibration isolation support for the sound absorption section, and a sample installation section installed at one end of the impedance tube sound absorption section. The integrated sound source is installed at the other end of the impedance tube sound absorption section, and a first microphone slot is provided in the impedance tube sound absorption section;

[0009] The sound insulation test module includes a vibration isolation support for the sound insulation section, an impedance tube sound insulation section installed on the vibration isolation support for the sound insulation section, and a sample positioning section installed at the front end of the impedance tube sound insulation section. The position of the sample positioning section is adjustable, and a second microphone slot is provided in the impedance tube sound insulation section;

[0010] The data acquisition and analysis module includes a number of microphones respectively inserted into the first microphone slot and the second microphone slot, and a data acquisition instrument connected to the microphones through a data transmission line;

[0011] And a sample picking and installation module arranged beside the sound absorption test module and the sound insulation test module and used for picking, installing, and replacing samples;

[0012] When the sample positioning section moves to engage and seal with the sample installation section, a test cavity for forming and installing a test sample and communicating with the impedance tube sound absorption section is formed between them.

[0013] Further, the impedance tube sound insulation section is slidably arranged on the vibration isolation support for the sound insulation section, and a push-pull module for connecting and driving the impedance tube sound insulation section is further provided at the bottom of the vibration isolation support for the sound insulation section.

[0014] Furthermore, the push-pull module includes a push-pull stepper motor and a push-pull screw table connected to the push-pull stepper motor. The impedance tube sound insulation section is installed on the push-pull screw table. In this embodiment, the moving direction of the push-pull screw table is exactly parallel to the impedance tube sound absorption section. That is to say, during the process of the sample positioning section moving back and forth with the impedance tube sound insulation section, the sample positioning section realizes the engagement or disengagement with the sample installation section, so as to cooperate to complete the picking and placing of the sample.

[0015] Further, the sample positioning section is fixedly connected to the impedance tube sound insulation section by screws, and there are two forms between the sample positioning section and the impedance tube sound insulation section: front-end closed and front-end open.

[0016] Further, a terminal opening and closing module for controlling its opening and closing state is further provided at the end of the impedance tube sound insulation section.

[0017] Furthermore, the terminal opening and closing module includes an opening and closing screw table arranged perpendicular to the axial direction of the impedance tube sound insulation section, a terminal cover installed on the opening and closing screw table, and an opening and closing stepper motor connected to the opening and closing screw table. Similarly, during the process of the terminal cover moving with the opening and closing screw table, the impedance tube sound insulation section is closed or opened.

[0018] Further, the sample picking and installation module is a robotic arm with four degrees of freedom.

[0019] Further, the sample picking and installing module includes a base, a large arm, a tray part, a slide bar and an end clamp. The base is connected to the large arm through a first joint. The large arm supports and connects the tray part through a second joint. The slide bar can rotate by itself and is slidably arranged on the tray part in the vertical direction. The end clamp is installed at the bottom end of the slide bar.

[0020] Further, the system also includes a bottom plate control and drive module, which includes a bottom plate, an integrated power supply, a robot controller, a stepper motor controller and a stepper motor driver.

[0021] Further, there are two first microphone slots and two second microphone slots respectively.

[0022] Further, there is at least one set corresponding to the integrated sound source, sound absorption test module and sound insulation test module respectively.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] First, the test efficiency is improved: Since the limitation of traditional single-tube detection is broken through, multi-tube linkage acoustic testing is adopted. With a single sample picking and installing module cooperating with multiple impedance tubes for testing at the same time, and when testing the sound absorption coefficient, the phase error of the microphone is determined in advance in the form of a calibration factor, omitting the step of exchanging microphones during the test to eliminate the phase error, greatly improving the test efficiency and meeting the needs of large-scale engineering application tests.

[0025] Second, the test accuracy is improved: Since a sample picking and installing module is used in cooperation with a stepper motor screw slide device to replace the traditional manual installation of samples and impedance tubes, reducing the sound field distortion caused by the front and rear tube offset, misalignment and gap left due to manual installation operations, thus causing test errors; through mechanical automation installation, the installation accuracy and sealing performance can be improved, greatly improving the test accuracy.

[0026] Third, it has strong universality: The present invention can replace impedance tubes of different forms to adapt to test samples of different shapes and sizes, such as circular tubes, 50mm and 200mm square tubes and other forms of impedance tubes; for samples of different materials, different forms of end clamps of the sample picking and installing module can be replaced to meet the test requirements of various samples such as porous materials, acoustic metamaterials, rubber, film, plastic, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of the overall structure of the system of the present invention;

[0028] Figure 2 is a schematic diagram of the sample picking and installing module of the present invention;

[0029] Figure 3 Schematic diagram of an integrated sound source and an automated sound absorption test module;

[0030] Figure 4 Schematic diagram of an automated sound insulation test module;

[0031] Figure 5 Schematic diagrams of two forms of the sample positioning section, where (a) is the sample positioning section with a closed front end, and (b) is the sample positioning section with an open front end;

[0032] Figure 6 Schematic diagram of the push - pull module structure;

[0033] Figure 7 Schematic diagram of the end opening - closing module;

[0034] Figure 8 Schematic diagram of the data acquisition and analysis module;

[0035] Figure 9 Schematic diagram of the bottom plate control and drive system;

[0036] Figure 10 Schematic diagram when the system conducts the normal incidence sound absorption coefficient test;

[0037] Figure 11 Schematic diagram when the system conducts the normal incidence sound transmission loss test;

[0038] Explanation of the markings in the figure:

[0039] 1 is the sample picking and installing module, 2 is the sound absorption test module, 3 is the sound insulation test module, 4 is the data acquisition and analysis module, 5 is the bottom plate control and drive module; 1 - 1 is the base, 1 - 2 is the large arm, 1 - 3 is the tray part, 1 - 4 is the slide bar, 1 - 5 is the end fixture, 1 - 6 is the cable; 2 - 1 is the integrated sound source module, 2 - 2 is the impedance tube sound absorption section, 2 - 3 is the sample installation section, 2 - 4 is the sound absorption section vibration isolation support; 3 - 1 is the impedance tube sound insulation section, 3 - 2 is the sample positioning section, 3 - 3 is the push - pull module, 3 - 4 is the end opening - closing module, 3 - 5 is the sound insulation section vibration isolation support; 4 - 1 is the data acquisition instrument, 4 - 2 is the data transmission line, 4 - 3 is the microphone; 5 - 1 is the bottom plate, 5 - 2 is the integrated power supply, 5 - 3 is the robot controller, 5 - 4 is the stepper motor controller, 5 - 5 is the stepper motor driver; 3 - 3 - 1 is the push - pull stepper motor, 3 - 3 - 2 is the push - pull screw rod slide table; 3 - 4 - 1 is the end cover, 3 - 4 - 2 is the opening - closing stepper motor, 3 - 4 - 3 is the opening - closing screw rod slide table. Specific implementation method

[0040] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and gives the detailed implementation manner and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0041] In the following embodiments or examples, if there is no special description of the functional components or functional structures, it means that they are all conventional components or conventional structures adopted in the art to achieve the corresponding functions.

[0042] To meet the requirements of acoustic absorption and sound insulation testing and accurately obtain the acoustic properties of materials, etc., the present invention provides an automated rapid detection system for acoustic impedance tubes, and its structure can be seen Figures 1 to 9 as shown, including:

[0043] An integrated sound source, which is used to provide a stable and adjustable sound pressure signal;

[0044] The acoustic absorption test module 2, which includes a vibration isolation support 2-4 for the acoustic absorption section, an acoustic impedance tube acoustic absorption section 2-2 installed on the vibration isolation support 2-4 for the acoustic absorption section, and a sample installation section 2-3 installed at one end of the acoustic impedance tube acoustic absorption section 2-2. The other end of the acoustic impedance tube acoustic absorption section 2-2 is installed with the integrated sound source, and a first microphone slot is provided in the acoustic impedance tube acoustic absorption section 2-2;

[0045] The sound insulation test module 3, which includes a vibration isolation support 3-5 for the sound insulation section, an acoustic impedance tube sound insulation section 3-1 installed on the vibration isolation support 3-5 for the sound insulation section, and a sample positioning section 3-2 installed at the front end of the acoustic impedance tube sound insulation section 3-1. The position of the sample positioning section 3-2 is adjustable, and a second microphone slot is provided in the acoustic impedance tube sound insulation section 3-1;

[0046] The data acquisition and analysis module 4, which includes a plurality of microphones 4-3 respectively inserted into the first microphone slot and the second microphone slot, and a data acquisition instrument 4-1 connected to the microphones 4-3 through a data transmission line 4-2;

[0047] And a sample picking and installation module 1 arranged beside the acoustic absorption test module 2 and the sound insulation test module 3 and used for picking, installing, and replacing samples;

[0048] When the sample positioning section 3-2 moves to be joined and sealed with the sample installation section 2-3, a test cavity is formed therebetween for installing a test sample and communicating with the acoustic impedance tube acoustic absorption section 2-2.

[0049] The microphone slot leads directly from the outer wall of the impedance tube to the inner wall of the impedance tube. There is a thin sealing and positioning ring near the inner wall of the impedance tube. The microphone 4-3 is inserted along the slot from the outer wall of the impedance tube and leads directly to the sealing and positioning ring, so that the microphone can effectively collect the sound pressure signal inside the impedance tube.

[0050] In some specific embodiments, the impedance tube sound insulation section 3-1 is slidably arranged on the sound insulation section vibration isolation support 3-5, and a push-pull module 3-3 for connecting and driving the impedance tube sound insulation section 3-1 is further provided at the bottom of the sound insulation section vibration isolation support 3-5.

[0051] In a more specific embodiment, the push-pull module 3-3 includes a push-pull stepper motor 3-3-1 and a push-pull screw rod slide table 3-3-2 connected to the push-pull stepper motor 3-3-1, and the impedance tube sound insulation section 3-1 is installed on the push-pull screw rod slide table 3-3-2. In this embodiment, the moving direction of the push-pull screw rod slide table 3-3-2 is exactly parallel to the impedance tube sound absorption section 2-2. That is to say, during the process of the sample positioning section 3-2 moving back and forth with the impedance tube sound insulation section 3-1, the sample positioning section 3-2 realizes the engagement or disengagement with the sample installation section 2-3, so as to complete the picking and placing of the sample.

[0052] In some specific embodiments, the sample positioning section 3-2 is fixedly connected to the impedance tube sound insulation section 3-1 by screws, and there are two forms between the sample positioning section 3-2 and the impedance tube sound insulation section 3-1: front-end closed type and front-end open type.

[0053] In some specific embodiments, a terminal opening and closing module 3-4 for controlling its opening and closing state is further provided at the end of the impedance tube sound insulation section 3-1.

[0054] In a more specific embodiment, the terminal opening and closing module 3-4 includes an opening and closing screw rod slide table 3-4-3 arranged along the axial direction perpendicular to the impedance tube sound insulation section 3-1, a terminal cover 3-4-1 installed on the opening and closing screw rod slide table 3-4-3, and an opening and closing stepper motor 3-4-2 connected to the opening and closing screw rod slide table 3-4-3. Similarly, during the process of the terminal cover 3-4-1 moving with the opening and closing screw rod slide table 3-4-3, the impedance tube sound insulation section 3-1 is closed or opened.

[0055] In some specific embodiments, the sample picking and installing module 1 is a robotic arm with four degrees of freedom.

[0056] In some specific embodiments, the sample picking and installing module 1 includes a base 1-1, a large arm 1-2, a tray part 1-3, a slide rod 1-4 and a terminal clamp 1-5. The base 1-1 and the large arm 1-2 are connected by a first joint. The large arm 1-2 and a second joint support and connect the tray part 1-3. The slide rod 1-4 can rotate by itself and is slidably arranged on the tray part 1-3 in the vertical direction. The terminal clamp 1-5 is installed at the bottom end of the slide rod 1-4.

[0057] In some specific embodiments, the system further includes a base plate control and drive module 5, which includes a base plate 5-1, an integrated power supply 5-2, a robot controller 5-3, a stepper motor controller 5-4, and a stepper motor driver 5-5.

[0058] In some specific embodiments, there are two first microphone slots and two second microphone slots respectively.

[0059] In some specific embodiments, there is at least one set of the integrated sound source, the sound absorption test module 2, and the sound insulation test module 3 respectively.

[0060] The system of the present invention performs sound absorption and insulation performance tests, including the following steps:

[0061] For the test methods of parameters such as the normal incidence sound absorption coefficient and the specific acoustic impedance, please refer to Figure. Microphones A1 and A2 belonging to impedance tube A, microphones B1 and B2 belonging to impedance tube B... ( Figure 1 Only two-tube tests are shown here, and multi-tube linkage tests of more impedance tubes C, D, E... can be carried out), and the sound absorption performance test methods of all impedance tubes are exactly the same)

[0062] The test steps are as follows:

[0063] First step, preparation work: Turn on the built-in speaker of the integrated sound source, and the built-in speaker is in a continuous working state during the whole test process; the sample positioning section 3-2 adopts an end-closed layout form, that is, the port between the sample positioning section 3-2 and the impedance tube sound insulation section 3-1 is closed and separated; insert the microphones A1 and A2 into the microphone slots of the impedance tube A correspondingly, such as Figure 10 ;

[0064] Second step, the sample picking and installation module 1 precisely controls and completes the sample installation work; the push-pull screw slide 3-3-2 precisely controls the sample positioning section 3-2 of the impedance tube sound insulation section 3-1 to be joined with the sample installation section 2-3 and has good sealing;

[0065] Third step, the data acquisition instrument 4-1 collects the time-domain sound pressure signals of the microphones A1 and A2 and calculates the complex transfer function The calculation method is as follows:

[0066]

[0067] In the formula: is the real part of; H i I is the imaginary part of; S 12 is the cross-spectrum of the signal of microphone A1 and the signal of microphone A2; S 11 is the auto-spectrum of the signal of microphone A1.

[0068] Step 4: Swap the positions of microphones A1 and A2, and insert them into microphone slots A2 and A1 correspondingly. Then collect the time-domain sound pressure signals of the microphones again and calculate the complex transfer function. The calculation method is as follows:

[0069]

[0070] In the formula: is the real part of ; H i II is the imaginary part of ; S 21 is the cross-spectrum of the signal of microphone A2 and the signal of microphone A1; S 22 is the auto-spectrum of the signal of microphone A2.

[0071] Step 5: For subsequent batch testing, insert microphones A1 and A2 back into the microphone slots of impedance tube A correspondingly; calculate the calibration factor, and the calculation method is as follows:

[0072]

[0073] Step 6: Calculate the transfer functions H I and H R , and the calculation method is as follows:

[0074]

[0075] In the formula: the wave number k0 = k′0 - jk″0, k′0 = 2π / λ0, where λ0 is the sound wave wavelength, f is the frequency, c0 is the speed of sound in air, d is the ratio of the diameter (for a circular tube) or 4 times the cross-sectional area (for a rectangular tube) to the perimeter; s is the distance between microphones A1 and A2.

[0076] Step 7: Formal test: Collect the time-domain sound pressure signals of the microphones and calculate the complex transfer function H′ 12 , and the calculation method is as follows:

[0077]

[0078] Step 8: Calculate the transfer function H 12 and the acoustic normal incidence reflection factor r, and finally obtain the normal incidence sound absorption coefficient α and the acoustic impedance rate Z s , and the calculation method is as follows:

[0079]

[0080]

[0081]

[0082] Z s = R s + jX s = [(1 + r) / (1 - r)]ρc0

[0083] Where: r r is the real part of the reflection factor; r i is the imaginary part of the reflection factor; x1 is the distance from the sample to the farther microphone; is the phase angle of the reflection factor.

[0084] Step 9: The sample picking and installing module 1 precisely controls and completes the work of taking out the sample; the push-pull screw slide 3-3-2 precisely controls the separation of the sample positioning section 3-2 and the sample installation section 2-3 of the sound insulation section 3-1 of the impedance tube;

[0085] Step 10: After the sample of impedance tube A is installed and before the test starts, install the sample of impedance tube B, and repeat the second, seventh to ninth steps to complete the installation and test of the samples of impedance tubes B, C, D, E...;

[0086] Step 11: Repeat the second, seventh to tenth steps to achieve batch and rapid testing of parameters such as the normal incidence sound absorption coefficient and acoustic impedance rate of the sample.

[0087] Testing methods for parameters such as normal incidence sound transmission loss and transmission coefficient (it is necessary to use microphones A1, A2, A3, A4 belonging to impedance tube A, microphones B1, B2, B3, B4 belonging to impedance tube B...( Figure 1 only two-tube testing is shown here, and multi-tube linkage testing of more impedance tubes C, D, E... can be carried out), and the sound insulation performance testing methods of all impedance tubes are exactly the same):

[0088] Step 1: Turn on the built-in speaker of the integrated sound source, and the built-in speaker is in a continuous working state during the whole test process; the sample positioning section 3-2 adopts an end-open layout form, that is, the port between the sample positioning section 3-2 and the sound insulation section 3-1 of the impedance tube is open and connected; insert the microphones A1, A2, A3, A4 into the microphone slots of impedance tube A correspondingly;

[0089] Step 2: The sample picking and installing module 1 precisely controls and completes the sample installation work; the push-pull screw slide 3-3-2 precisely controls the engagement and good sealing of the sample positioning section 3-2 and the sample installation section 2-3 of the sound insulation section 3-1 of the impedance tube;

[0090] Step 3: The data acquisition instrument 4-1 collects the time-domain sound pressure signals of the microphones and calculates the complex transfer function H 1，i from microphone A1 to microphone Ai, and the calculation method is:

[0091]

[0092] Where: S 1i is the cross-spectrum of the signals of microphone A1 and microphone Ai; S11 is the auto-spectrum of the signal of microphone A1.

[0093] In the fourth step, the opening and closing screw rod slide 3-4-3 controls the opening and closing of the end cap 3-4-1, and the time-domain sound pressure signals of microphones A1, A2, A3, and A4 are collected respectively for the two working conditions of opening and closing the end of the impedance tube. Measured within the cut-off frequency range of the impedance tube, the sound field before and after the sample is decomposed into plane waves propagating left and right. A and B are the incident wave and the reflected wave near the sound source end respectively, and C and D are the incident wave and the reflected wave far from the sound source end respectively, as Figure 11 ;

[0094]

[0095]

[0096] Where: the wave number k = k′ - jk″, k′ = 2π / λ0,

[0097] In the fifth step, calculate the sound pressure p and the particle velocity u on both sides of the sample. The calculation method is (suffix 0 is for the left side, suffix d is for the right side; ρ is the air density):

[0098]

[0099] In the sixth step, perform the transfer matrix calculation according to the measurement results of the two working conditions of opening and closing the end of the impedance tube (suffix a is for the open end, suffix b is for the closed end). The calculation method is:

[0100]

[0101] In the seventh step, calculate the normal transmission coefficient τ p , and finally obtain the normal incident sound transmission loss TL. The calculation method is:

[0102]

[0103] In the eighth step, the sample picking and installation module 1 precisely controls and completes the work of taking out the sample; the push-pull screw rod slide 3-3-2 precisely controls the separation of the sample positioning section 3-2 of the sound insulation section 3-1 of the impedance tube from the sample installation section 2-3;

[0104] In the ninth step, after the sample of impedance tube A is installed and before the test starts, install the sample of impedance tube B, and repeat the second to eighth steps to complete the installation and test of the samples of impedance tubes B, C, D, E...

[0105] Step 10: Repeat Steps 2 to 9 to achieve batch and rapid testing of parameters such as the normal incidence sound transmission loss and transmission coefficient of the sample.

[0106] Each of the above embodiments can be implemented independently, or can be combined in any pair or in more combinations.

[0107] The above embodiments will be described in more detail below with reference to specific examples.

[0108] Example 1:

[0109] This example provides an automated rapid acoustic impedance tube detection system, and its structure is shown in Figures 1 to 9 and includes:

[0110] An integrated sound source, which is used to provide a stable and adjustable sound pressure signal;

[0111] An absorption test module 2, which includes an absorption section vibration isolation support 2-4, an impedance tube absorption section 2-2 installed on the absorption section vibration isolation support 2-4, and a sample installation section 2-3 installed at one end of the impedance tube absorption section 2-2. The integrated sound source is installed at the other end of the impedance tube absorption section 2-2, and a first microphone slot is provided in the impedance tube absorption section 2-2;

[0112] A sound insulation test module 3, which includes a sound insulation section vibration isolation support 3-5, an impedance tube sound insulation section 3-1 installed on the sound insulation section vibration isolation support 3-5, and a sample positioning section 3-2 installed at the front end of the impedance tube sound insulation section 3-1. The position of the sample positioning section 3-2 is adjustable, and a second microphone slot is provided in the impedance tube sound insulation section 3-1;

[0113] A data acquisition and analysis module 4, which includes a number of microphones 4-3 respectively inserted into the first microphone slot and the second microphone slot, and a data acquisition instrument 4-1 connected to the microphones 4-3 through a data transmission line 4-2;

[0114] And a sample picking and installation module 1 arranged beside the absorption test module 2 and the sound insulation test module 3 and used for picking, installing, and replacing samples;

[0115] When the sample positioning section 3-2 moves to be joined and sealed with the sample installation section 2-3, a test cavity is formed therebetween for installing a test sample and communicating with the impedance tube absorption section 2-2.

[0116] Please refer to Figure 2As shown in the figure, the sample picking and installation module 1 includes a base 1-1, a large arm 1-2, a tray part 1-3, a slide bar 1-4, an end fixture 1-5, and a cable 1-6. Among them, the base 1-1 and the large arm 1-2 are connected by a first joint; the large arm 1-2 supports and connects the tray part 1-3 through a second joint; the first joint and the second joint work together to drive the slide bar 1-4 to move in the horizontal plane along a planned path; the slide bar 1-4 itself is a third joint that drives the end fixture 1-5 to move up and down and rotate around a fixed axis in the vertical direction; the end fixture 1-5 is a fourth joint for picking up the sample. In this embodiment, the sample picking and installation module 1 uses an HSR-SR6600 four-degree-of-freedom robotic arm produced by Huashu Robotics Co., Ltd. The maximum working radius is 600 mm, which can meet the sample placement and removal actions during the operation of the dual impedance tube. The maximum working range of its first joint is ±132°, and the repeat positioning accuracy is ±0.02 mm; the maximum working range of the second joint is ±150°, and the repeat positioning accuracy is ±0.02 mm; the maximum working range of the third joint is 200 mm, and the repeat positioning accuracy is ±0.01 mm; the maximum working range of the fourth joint is ±360°, and the repeat positioning accuracy is ±0.01°, which meets the actions such as sample grasping, moving, and placing; the high-speed cycle time of the robotic arm is as low as 0.4 s, and the rated load is 2 kg. Other models of robotic arms can be selected to change the maximum working radius to meet the test requirements of multi-tube (dual tubes and above) linkage tests.

[0117] Please refer to again Figure 3 As shown in the figure, the integrated sound source is installed at one end of the sound absorption test module 2. The sound absorption test module 2 includes an impedance tube sound absorption section 2-2, a sample installation section 2-3, and a sound absorption section vibration isolation support 2-4; the impedance tube sound absorption section 2-2 and the sample installation section 2-3 are connected by bolts; the sample installation section 2-3 is used to combine with the sample positioning section 3-2 to install and seal the sample well, and the sound absorption section vibration isolation support 2-4 is used to fix the sound absorption test module 2 on the bottom plate 5-1. The plane wave generated by the integrated sound source module 2-1 in this embodiment is a full-frequency pseudo-random sequence white noise. The impedance tube sound absorption section 2-2 can be selected as a circular tube (the inner size is generally or ), a square tube (the inner size is generally 50 mm * 50 mm, 100 mm * 100 mm, or 200 mm * 200 mm), or a rectangular tube, and the material can be selected from metal or transparent acrylic plate material.

[0118] Please refer to again Figure 4As shown in etc., the sound insulation test module 3 includes an impedance tube sound insulation section 3-1, a specimen positioning section 3-2, a push-pull module 3-3, an end opening and closing module 3-4, and a sound insulation section vibration isolation support 3-5; the specimen positioning section 3-2 has two forms: front-end closed and front-end open, and is connected to the impedance tube sound insulation section 3-1 by bolts; the push-pull module 3-3 includes a push-pull stepper motor 3-3-1 and a push-pull lead screw slide 3-3-2, and is connected to the sound insulation section vibration isolation support 3-5 by bolts, carrying the impedance tube sound insulation section 3-1 and meeting the combined actions of the specimen installation section 2-3 and the specimen positioning section 3-2; the end opening and closing module 3-4 controls the opening and closing of the end cover 3-4-1, meeting the two conditions of the open end and the closed end of the sound insulation test, so as to complete the test of the normal incidence sound transmission loss. In this embodiment, the cross-sectional configuration and material of the impedance tube sound insulation section 3-1 and the impedance tube sound absorption section 2-2 are exactly the same; the push-pull stepper motor 3-3-1 and the opening and closing stepper motor 3-4-2 in the push-pull module 3-3 and the end opening and closing module 3-4 are 5718HB3401 type stepper motors with a torque of 2.3 N·m, meeting the movement of the push-pull lead screw slide 3-3-2 and the opening and closing lead screw slide 3-4-3.

[0119] Please refer to again Figure 8 As shown in, the data acquisition and analysis module 4 includes a data acquisition instrument 4-1, a data transmission line 4-2, and a microphone 4-3; the microphone 4-3 is connected to the data acquisition instrument 4-1 through the data transmission line 4-2 and is inserted into the microphone slots of the impedance tube sound absorption section 2-2 and the impedance tube sound insulation section 3-1; the microphone 4-3 collects the time-domain sound pressure signal and transmits it to the data acquisition instrument 4-1 through the data transmission line 4-2, and finally transmits the processing result to the computer for calculating the normal incidence sound absorption coefficient and the sound transmission loss. In this embodiment, two 4-channel data acquisition instruments 4-1 produced by National Instruments Corporation are selected for the data acquisition instrument 4-1, and eight 1 / 2 microphones 4-3 produced by Beijing Shengyang Acoustic-Electric Technology Co., Ltd. are selected for the microphone 4-3.

[0120] Please refer to again Figure 9As shown in the figure, the bottom plate control drive module 5 includes a bottom plate 5-1, an integrated power supply 5-2, a robot controller 5-3, a stepper motor controller 5-4, and a stepper motor driver 5-5; the integrated power supply 5-2, the robot controller 5-3, the stepper motor controller 5-4, and the stepper motor driver 5-5 are all installed on the bottom plate 5-1; the sample picking and installing module 1, the integrated sound source, the sound absorption test module 2, the sound insulation test module 3, and the data acquisition and analysis module 4 are also installed on the bottom plate 5-1. In this embodiment, the integrated power supply 5-2 uses a 220V AC power supply and a 24V DC power supply, and the robot controller 5-3 selects a controller produced by Huashu Robotics Co., Ltd. and supporting the HSR-SR6600 four-degree-of-freedom robotic arm. The stepper motor controller 5-4 selects an SM2P two-axis programmable stepper servo motor controller, and the stepper motor driver 5-5 selects a Pufide 57 stepper motor set, with the driver model DM542 and the stepper motor torque of 2.3N. m 。

[0121] The test steps for parameters such as the normal incidence sound absorption coefficient and the specific acoustic impedance rate are as follows: First step, turn on the built-in speaker of the integrated sound source; insert the microphone into the microphone slot of the impedance tube A correspondingly. Second step, the sample picking and installing module 1 precisely controls and completes the sample installation work; the push-pull screw slide 3-3-2 precisely controls the engagement of the sample positioning section 3-2 and the sample installation section 2-3 and ensures good sealing. Third step, the data acquisition instrument 4-1 collects the time-domain sound pressure signal of the microphone and calculates the complex transfer function Fourth step, switch the position of the microphone, insert it into the microphone slot correspondingly, collect the time-domain sound pressure signal of the microphone again, and calculate the complex transfer function Fifth step, insert the microphone into the microphone slot of the impedance tube correspondingly and calculate the calibration factor. Sixth step, calculate the transfer functions H I and H R of the incident wave and the reflected wave. Seventh step, official test: collect the time-domain sound pressure signal of the microphone and calculate the complex transfer function H′ 12 . Eighth step, calculate the transfer function H 12 and the sound normal incidence reflection factor r, and finally obtain the normal incidence sound absorption coefficient α. Ninth step, the sample picking and installing module 1 precisely controls and completes the sample removal work; the push-pull screw slide 3-3-2 precisely controls the separation of the sample positioning section 3-2 and the sample installation section 2-3. Tenth step, after the sample is installed in the impedance tube A and before the test starts, install the sample in the impedance tube B, repeat the second, seventh to ninth steps, and complete the installation and test of the samples in the impedance tubes B, C, D, E... Eleventh step, repeat the second, seventh to tenth steps to achieve batch and rapid testing of parameters such as the normal incidence sound absorption coefficient and the specific acoustic impedance rate.

[0122] The test steps for parameters such as normal incidence sound transmission loss and transmission coefficient are as follows: First step, turn on the built-in speaker of the integrated sound source; insert the microphone into the microphone slot of impedance tube A correspondingly. Second step, the sample picking and installation module 1 precisely controls and completes the sample installation work; the push-pull screw slide 3-3-2 precisely controls the engagement of the sample positioning section 3-2 and the sample installation section 2-3 and ensures good sealing. Third step, the data acquisition instrument 4-1 collects the time-domain sound pressure signal of the microphone and calculates the complex transfer function H from microphone A1 to microphone Ai. 1，i . Fourth step, the opening and closing screw slide 3-4-3 controls the opening and closing of the end cap 3-4-1. Respectively collect the time-domain sound pressure signals of the microphone for the two working conditions of opening and closing the end of the impedance tube, measure within the cut-off frequency range of the impedance tube, decompose the sound fields before and after the sample into plane waves propagating left and right, where A and B are the incident wave and the reflected wave near the sound source end respectively, and C and D are the incident wave and the reflected wave far from the sound source end respectively. Fifth step, calculate the sound pressure p and particle velocity u on both sides of the sample. Sixth step, perform transfer matrix calculation according to the measurement results of the two working conditions of opening and closing the end of the impedance tube. Seventh step, calculate the normal transmission coefficient τ p , and finally obtain the normal incidence sound transmission loss TL. Eighth step, the sample picking and installation module 1-1 precisely controls and completes the sample removal work; the push-pull screw slide 3-3-2 precisely controls the separation of the open sample positioning section 3-2 and the sample installation section 2-3. Ninth step, after the sample installation in impedance tube A is completed and before the test starts, perform the sample installation in impedance tube B, repeat the second to eighth steps, and complete the installation and test of the samples in impedance tubes B, C, D, E... Tenth step, repeat the second to ninth steps to achieve batch and rapid testing of parameters such as normal incidence sound transmission loss and transmission coefficient.

[0123] The above description of the embodiments is for the convenience of those of ordinary skill in the art to understand and use the invention. Obviously, those who are familiar with the technology in this field can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative labor. Therefore, the present invention is not limited to the above embodiments, and the improvements and modifications made by those skilled in the art without departing from the scope of the present invention according to the disclosure of the present invention should be within the protection scope of the present invention.

Claims

1. An automated acoustic impedance tube rapid detection system, characterized in that, Comprising: An integrated sound source for providing a stable and adjustable sound pressure signal; An acoustic absorption test module, which includes an acoustic absorption section vibration isolation support, an impedance tube acoustic absorption section mounted on the acoustic absorption section vibration isolation support, and a specimen mounting section mounted at one end of the impedance tube acoustic absorption section. The other end of the impedance tube acoustic absorption section is mounted with the integrated sound source, and a first microphone slot is provided in the impedance tube acoustic absorption section; A sound insulation test module, which includes a sound insulation section vibration isolation support, an impedance tube sound insulation section mounted on the sound insulation section vibration isolation support, and a specimen positioning section mounted at the front end of the impedance tube sound insulation section. The position of the specimen positioning section is adjustable, and a second microphone slot is provided in the impedance tube sound insulation section; A data acquisition and analysis module, which includes a plurality of microphones respectively inserted into the first microphone slot and the second microphone slot, and a data acquisition instrument connected to the microphones through a data transmission line; And a specimen picking and mounting module arranged beside the acoustic absorption test module and the sound insulation test module for picking, mounting, and replacing specimens; When the specimen positioning section moves to engage and seal with the specimen mounting section, a test cavity is formed therebetween for mounting a test specimen and communicating with the impedance tube acoustic absorption section; A terminal opening and closing module for controlling the opening and closing state is further provided at the end of the impedance tube sound insulation section; The specimen picking and mounting module is a robotic arm with four degrees of freedom; The specimen picking and mounting module includes a base, a large arm, a tray part, a sliding rod, and a terminal fixture. The base is connected to the large arm through a first joint. The large arm supports and connects the tray part through a second joint. The sliding rod can rotate by itself and is slidably arranged vertically on the tray part. The terminal fixture is mounted at the bottom of the sliding rod.

2. The automated acoustic impedance tube rapid detection system according to claim 1, wherein The impedance tube sound insulation section is slidably arranged on the sound insulation section vibration isolation support, and a pushing and pulling module for connecting and driving the impedance tube sound insulation section is further provided at the bottom of the sound insulation section vibration isolation support.

3. The automated acoustic impedance tube rapid detection system according to claim 2, characterized in that, The pushing and pulling module includes a pushing and pulling stepper motor and a pushing and pulling screw rod slide table connected to the pushing and pulling stepper motor. The impedance tube sound insulation section is mounted on the pushing and pulling screw rod slide table.

4. An automated acoustic impedance tube rapid detection system according to claim 1, characterized in that, The specimen positioning section is fixedly connected to the impedance tube sound insulation section by screws, and there are two forms between the specimen positioning section and the impedance tube sound insulation section: front-end closed and front-end open.

5. An automated acoustic impedance tube rapid detection system according to claim 1, characterized in that, The terminal opening and closing module includes an opening and closing screw rod slide table arranged perpendicular to the axial direction of the impedance tube sound insulation section, a terminal cover mounted on the opening and closing screw rod slide table, and an opening and closing stepper motor connected to the opening and closing screw rod slide table.

6. An automated acoustic impedance tube rapid detection system according to claim 1, characterized in that, The system further includes a baseboard control and drive module, which includes a baseboard, an integrated power supply, a robot controller, a stepper motor controller, and a stepper motor driver. The integrated power supply, the robot controller, the stepper motor controller, and the stepper motor driver are all mounted on the baseboard.

7. An automated acoustic impedance tube rapid detection system according to claim 1, characterized in that, There are two first microphone slots and two second microphone slots respectively.

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