Rigid ball array sound field testing device and noise source positioning method

Abstract

The invention relates to the technical field of acoustics, and particularly discloses a rigid ball array sound field testing device and a noise source positioning method, and the method comprises the following steps: collecting noise data in a target environment through employing a spherical microphone array, reading and processing the collected noise data, and obtaining frequency domain sound pressure data; taking the frequency domain sound pressure data as input data of a sound field reconstruction algorithm; calculating an approximate undetermined coefficient according to the input data in combination with a spherical near-field acoustical holography technology; reconstructing an original incident sound field according to the approximate undetermined coefficient; according to an original incident sound field, sound pressure distribution at any position of a space sound field around the spherical microphone array is reconstructed, so that the direction of a noise source is identified, and the system has the advantages of stable structure, high resolution, real-time processing and good anti-interference capability.

Description

Technical Field

[0001] The present invention relates to the field of acoustic technology, and more specifically, to a rigid ball array sound field testing device and a noise source positioning method. Background Art

[0002] As the speed of elevators continues to increase, they bring great noise interference to people during actual operation. The noise generated by complex vibrations and high-speed airflow greatly reduces the comfort and safety of passengers riding in elevators. Therefore, how to reduce drag and noise has become a difficult problem that the elevator industry needs to solve urgently. In order to control the noise of elevator operation, it is necessary to measure and analyze the noise source, understand the mechanism and characteristics of noise generation, reconstruct the sound field in the elevator car, and determine the location of the noise source. To effectively control the noise source, it is necessary to have a deep understanding of the location distribution, phase, amplitude, and frequency characteristics of the noise source in order to effectively deal with the noise source.

[0003] Traditional measurement methods include: near-field measurement, surface velocity measurement, spectrum analysis, sound intensity, etc. The disadvantages of traditional measurement technology include large workload, unguaranteed measurement accuracy, and great limitations. In the positioning of noise sources in three-dimensional closed spaces in ultra-high-speed elevator cars, microphone arrays are used as the measurement front end for sound field reconstruction. A relatively simple method is the planar microphone array, but the limitation of the planar array is that it cannot distinguish the sound in front of or behind the array. The complex sound field environment inside the closed car increases the difficulty of sound source positioning. The spherical array has three-dimensional symmetry and omnidirectionality. Its special structure makes it very flexible and has a fast measurement speed, which greatly improves the efficiency of information collection in the three-dimensional sound field. After the spherical array obtains the collected sound field pressure data, it performs signal transformation and processing, and then uses a suitable sound field reconstruction algorithm to reconstruct the three-dimensional sound field to realize the positioning of the noise source in the closed space. In the study of acoustic holography, one of the key issues is how to obtain accurate holographic data containing amplitude and phase. As the spherical array is used as the measurement front end, the accuracy of the measured sound pressure data has a great influence on the accuracy of the sound field reconstruction results.

[0004] In view of this, the present invention provides a rigid ball array sound field testing device and a noise source positioning method to solve the above problems. Summary of the invention

[0005] In order to overcome the problems in the prior art, the present invention proposes a rigid spherical array sound field testing device and a noise source localization method, which can cope with complex target environments in real time through the application of adaptive image preprocessing and hybrid ranging algorithms.

[0006] The present invention provides a noise source locating method, comprising the following steps:

[0007] S1. Place the rigid ball array sound field test device in the target environment and collect noise data;

[0008] S2, reading the noise data collected in step S1, performing FFT processing on the noise data to obtain frequency domain sound pressure data, and using the frequency domain sound pressure data as input data of the sound field reconstruction algorithm;

[0009] S3, calculating the approximate unknown coefficients according to the input data obtained in step S2 in combination with the spherical near-field acoustic holography method;

[0010] S4. Reconstruct the original incident sound field according to the approximate unknown coefficients; reconstruct the sound pressure distribution at any position of the spatial sound field around the spherical microphone array according to the original incident sound field, so as to identify the direction of the noise source.

[0011] As a preferred technical solution of the present invention, the configuration information corresponding to the rigid spherical array sphere includes the array radius, the number of microphones and the position distribution of each microphone. The position distribution of each microphone can also be described as a distribution of discrete points, which means that each microphone is used as a point for data collection;

[0012] The logic for obtaining the configuration information corresponding to the rigid sphere array sphere is as follows:

[0013] The center position of the environment is obtained based on the target environment, and the center position of the rigid sphere array is determined. Then, the rigid sphere array is in the near field of the sound source, and the array radius is determined based on the spatial size of the target environment;

[0014] Determine the number of microphones and the distribution of each discrete point based on a spherical numerical integration method, wherein each microphone is symmetrically distributed on a sphere;

[0015] As a preferred technical solution of the present invention, the analysis logic of the geometric distribution and corresponding weights of the microphones on the rigid spherical array sphere includes:

[0016] Configure a regular polyhedron whose center is the same as the center of the sphere, and adjust the size of the regular polyhedron so that its vertices are on the sphere. Then the positions of the vertices of this regular polyhedron are the distribution positions of the required discrete points on the sphere.

[0017] Using different regular polyhedrons to perform symmetrical twisting about the rotation axis can also generate spherical optimization with a certain number of discrete points with different array radii;

[0018] The spherical integral form is converted into the superposition of the values ​​at each discrete point to obtain the corresponding weight. Since each discrete point is spherically symmetric, it can be seen that the integral weights of these discrete integral points are equal.

[0019] As a preferred technical solution of the present invention, a spherical near-field acoustic holography algorithm is used to reconstruct the sound field. The established model takes into account the sound wave scattering on the surface of a rigid sphere. The sound field reconstruction is corrected by the Neumann boundary condition, and the original incident sound pressure distribution at any position in the spatial sound field around the spherical microphone array is reconstructed to identify the direction of the noise source.

[0020] As a preferred technical solution of the present invention, supporting software is designed and developed for data acquisition, signal processing and analysis, sound field reconstruction and noise source visualization positioning, and the noise source visualization positioning results are displayed on the human-computer interaction interface.

[0021] In a second aspect, the present invention provides a rigid ball array sound field testing device, based on the implementation of a noise source positioning method described in the first aspect, comprising a rigid ball array sphere, the rigid ball array sphere being fixed to a base through a retractable connecting tube;

[0022] The rigid ball array sphere is provided with microphone channels adapted to the microphones evenly arranged on the spherical surface according to the spherical numerical integration method; one end of the microphone with the microphone is exposed on the outer surface of the rigid ball array sphere and is flush with the outer surface of the rigid ball array sphere; the other end of the microphone is inside the rigid ball array sphere and is connected to a wire; a large hole is provided at the bottom of the rigid ball array sphere for inserting one end of a telescopic connecting tube; the other end of the telescopic connecting tube is inserted into the mounting hole on the base; the wire is connected to a signal collector in the inner cavity of the base based on the mounting hole; the signal collector is connected to an electronic device at a vacant position on the outer surface of the base.

[0023] As a preferred technical solution of the present invention, the rigid ball array sphere includes a rigid ball array upper hemisphere and a rigid ball array lower hemisphere; the rigid ball array upper hemisphere and the rigid ball array lower hemisphere are fixedly connected, and microphone channels are arranged on the rigid ball array upper hemisphere and the rigid ball array lower hemisphere.

[0024] As a preferred technical solution of the present invention, the telescopic connecting tube is fixed by a clamp, and the clamp includes a clamp hole for fixing the telescopic connecting tube, and the clamp hole is loosened or tightened by a threaded knob.

[0025] In a third aspect, the present invention provides an electronic device, comprising: a processor and a memory, wherein the memory stores a computer program that can be called by the processor;

[0026] The processor executes the noise source localization method described in the first aspect by calling the computer program stored in the memory.

[0027] In a fourth aspect, the present invention provides a computer-readable storage medium storing instructions, which, when executed on a computer, enable the computer to execute the noise source localization method described in the first aspect.

[0028] The specific advantages of the present invention are as follows:

[0029] The sound field reconstruction device of the present invention realizes high-precision measurement and reconstruction of sound pressure distribution in three-dimensional space through a spherical microphone array and advanced acoustic holography technology. It has stable structure, high resolution, real-time processing and good anti-interference ability, and is suitable for a wide range of acoustic measurement and noise control scenarios. It is highly integrated, easy to use and scalable, providing users with a one-stop sound field analysis solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a flow chart of the three-dimensional closed space sound field reconstruction method of the present invention;

[0031] Figure 2 This is a structural diagram of the rigid ball array device of the present invention;

[0032] Figure 3 This is a structural diagram of the upper hemisphere of the rigid ball array of the present invention;

[0033] Figure 4 This is a structural diagram of the lower hemisphere of the rigid ball array of the present invention;

[0034] Figure 5 This is a structural diagram of the telescopic connecting pipe of the present invention;

[0035] Figure 6 This is a structural diagram of the clamp of the present invention;

[0036] Figure 7 This is a structural diagram of the base of the present invention;

[0037] Figure 8 This is a diagram showing the effect of the rigid ball array device of the present invention being used in conjunction with the sound source device. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] The rigid ball array device is a spherical microphone array with a rigid surface. The specific reason is that there are currently two types of spherical microphone arrays, one is a hollow ball array and the other is a rigid ball array. For the hollow ball array, the measurement accuracy is reduced due to the introduction of factors such as microphone brackets and wires into the sound field during application. For the rigid ball array, the microphone is embedded in a rigid spherical shell, which is easier to manufacture and more stable in structure. More importantly, the rigid ball array has more stable boundary conditions in all frequency ranges, so it is relatively more promising. Compared with the traditional two-dimensional microphone array, the spherical microphone array has three-dimensional rotational symmetry and can measure the three-dimensional spatial distribution of sound pressure. Therefore, it has unique advantages in applications such as sound field reconstruction in closed spaces and sound source identification and positioning.

[0040] During the implementation process, the array radius and the number of microphones can be set according to the actual needs of the elevator car while ensuring the reconstruction accuracy. Several microphones are evenly and equally distributed on the upper and lower hemispheres of the rigid sphere array. The geometric layout of the microphones on the surface of the rigid sphere array and the corresponding integral weights are set to improve the accuracy of sound field reconstruction.

[0041] Example 1: Please refer to Figure 2-7 , This embodiment provides a rigid ball array sound field testing device, including a rigid ball array sphere, and the rigid ball array sphere is fixed to a base 5 through a retractable connecting tube 3;

[0042] The rigid ball array sphere includes a rigid ball array upper hemisphere 1 and a rigid ball array lower hemisphere 2; the rigid ball array upper hemisphere 1 and the rigid ball array lower hemisphere 2 are fixedly connected, and the fixed connection method is not limited to threaded connection or bolt fixing.

[0043] Specifically, the microphone is fixed on the rigid ball array sphere according to the processing standard to realize the effective collection of noise data at the optimized spherical discrete points. It is not limited whether the rigid ball array sphere must be set separately. However, the reason for using a split rigid ball array sphere in this embodiment is: 1. The microphone is better installed on the rigid ball array sphere. The wire used by the microphone to transmit the signal is led out through the pipe inside the rigid ball array sphere. In addition, the split type can also make it more convenient for users to inspect and maintain.

[0044] like Figure 3 As shown, the upper hemisphere 1 of the rigid spherical array has four microphone channels 1-1, 1-2, 1-3, and 1-4 arranged on the surface of the upper hemisphere 1 of the rigid spherical array according to the spherical numerical integration method. The aperture of the microphone channel is adapted to the size of the microphone. One end of the microphone with the microphone is exposed on the outer surface of the spherical array and is flush with the outer surface. The other end of the microphone is inside the rigid spherical array and is connected to a wire.

[0045] like Figure 4 As shown, the lower hemisphere 2 of the rigid spherical array has four microphone channels 2-1, 2-2, 2-3, and 2-4 arranged on the surface of the lower hemisphere 2 of the rigid spherical array according to the spherical numerical integration method. The aperture of the microphone channel is adapted to the size of the microphone. One end of the microphone with the microphone is exposed on the outer surface of the spherical array and is flush with the outer surface. The other end of the microphone is inside the rigid spherical array and connected to a wire. A large hole 2-5 is provided at the bottom of the lower hemisphere of the rigid spherical array for inserting a retractable connecting tube 3.

[0046] Specifically: the aperture of the microphone channel is determined according to the size of the microphone, so that the microphone is just stably embedded in the channel. In this embodiment, an 8-channel microphone array is designed with a regular hexahedron, and the upper hemisphere 1 of the rigid spherical array and the lower hemisphere 2 of the rigid spherical array each have four microphone channels and are symmetrically distributed on the spherical surface; in practical applications, it is not limited to an 8-channel microphone array, as long as different regular polyhedrons are used to perform symmetrical twisting about the rotation axis, a certain number of discrete points with different array radii can be generated for spherical optimization, that is, the rigid spherical array sphere as a whole can be a 16-channel microphone array, a 24-channel microphone array, a 32-channel microphone array, or a 64-channel microphone array.

[0047] like Figure 5 As shown, the telescopic connecting tube 3 is used to connect the rigid ball array (the lower hemisphere 2 of the rigid ball array) with the base 5, and the telescopic connecting tube 3 includes a spiral connector 3-1 and a fixed connector 3-2;

[0048] Based on the spiral connector 3-1 being rotated and inserted into the large hole 2-5 at the bottom of the lower hemisphere 2 of the rigid ball array, the function of the spiral structure is to make the connection between the telescopic connecting tube 3 and the rigid ball array more secure. The telescopic connecting tube 3 can adjust the height of the rigid ball array as needed. The telescopic connecting tube 3 is hollow and stores the wire connected to the microphone.

[0049] like Figure 6 As shown, the clamp 4 is used to fix the telescopic connecting tube 3. The clamp 4 includes a clamp hole 4-1 for fixing the telescopic connecting tube 3, and a threaded knob 4-2 is provided on one side of the clamp hole 4-1. The threaded knob 4-2 is used to loosen or tighten the clamp hole 4-1, so as to facilitate the adjustment and fixation of the telescopic connecting tube 3.

[0050] Specifically, the size of the clamp hole 4 - 1 is set according to the telescopic connecting tube 3 .

[0051] like Figure 7As shown, the base 5 is in a rectangular shape and is hollow inside, and is used to place the array signal collector and the wires of each channel, so that the wires are standardized and neat; the outer surface of the base is closed, and the upper surface of the base is provided with a mounting hole 5-1, which is used to insert and fix the other end 3-2 of the telescopic connecting tube 3, and a mobile computer can be placed in the vacant position on the upper surface of the base 5 to process and store the collected noise data; the front surface 5-2 of the base is openable, and the signal collector is placed into the base from the open position, and the signal collector is connected to the microphone through a wire to collect noise data, and one end of the signal collector is connected to the power supply, and the other end is connected to the mobile computer.

[0052] In summary, the present embodiment adopts a rigid surface spherical microphone array, including a specific design of the upper hemisphere and the lower hemisphere, a retractable connecting tube, and the inlay and wire arrangement of the microphone, to provide stable boundary conditions and the ability to measure sound pressure at any position in three-dimensional space. The device structure is stable and reliable, with a high degree of integration. The measurement height can be adjusted according to the target environment. The surface of the spherical array is made of hard material to ensure rigidity and stability. The wires are stored in the hollow core of the device to avoid the influence of the wires exposed to the outside on data acquisition, thereby improving the accuracy of sound field reconstruction.

[0053] Example 2: Please refer to Figure 1 For the parts not described in detail in this embodiment, please refer to Embodiment 1. This embodiment provides a noise source positioning method, including the following steps:

[0054] S1. Place the rigid ball array sound field test device in the target environment and collect noise data;

[0055] Specifically, the target environment is not limited to a certain situation. In the research process, the elevator car is used as the specific application scenario of the target environment; the corresponding configuration information of the rigid spherical array sphere includes the array radius, the number of microphones and the position distribution of each microphone. The position distribution of each microphone can also be described as a discrete point distribution, which means that each microphone is used as a point for data collection;

[0056] The logic for obtaining the configuration information corresponding to the rigid sphere array sphere is as follows:

[0057] The center position of the environment is obtained based on the target environment, and the center position of the rigid sphere array is determined. Then the rigid sphere array is in the near field of the sound source, and the array radius is determined based on the spatial size of the target environment;

[0058] The number of microphones and the distribution of discrete points are determined based on a spherical numerical integration method, wherein the microphones are symmetrically distributed on a sphere.

[0059] It should be noted that the spherical numerical integration method includes the Spherical t-designs integration method; based on the Spherical t-designs integration method, the corresponding configuration information of the microphone on the rigid spherical array sphere is designed, the geometric distribution of the microphone on the sphere is optimized and the corresponding integration weights are determined, which simplifies the algorithm complexity, reduces the calculation time, and improves the accuracy of sound field reconstruction.

[0060] More specifically, the analysis logic of the geometric distribution of the microphones on the rigid spherical array sphere and the corresponding weights includes;

[0061] Configure a regular polyhedron whose center is the same as the center of the sphere, and adjust the size of the regular polyhedron so that its vertices are on the sphere. Then the positions of the vertices of this regular polyhedron are the distribution positions of the required discrete points on the sphere.

[0062] The method of twisting a regular polyhedron is adopted, that is, rotating the regular polyhedron along certain axes, which pass through the center of the sphere and are three-dimensionally symmetrical. The resulting twisted regular polyhedron can generate a spherical optimized distribution of a certain number of discrete points.

[0063] Using different regular polyhedrons to perform symmetrical twisting about the rotation axis can also generate spherical optimization with a certain number of discrete points with different array radii;

[0064] The spherical integral form is transformed into the superposition of the values ​​at each discrete point to obtain the corresponding weight. The superposition formula is:

[0065]

[0066] where x i =x1,...,x M are points on the sphere, w i represents the corresponding weight of each point, and f(x) is the function value on the sphere;

[0067] Since each discrete point is spherically symmetric, it can be seen that the integral weights of these discrete integral points are equal. The integral weight is marked as w. If the corresponding values ​​of all discrete integral points on the sphere are 1, then:

[0068] w=4π / M

[0069] That is, the integral weight in physical terms is one-Mth of the spherical area. Therefore, under a certain number of discrete points, the corresponding integral weights of each discrete point are equal, which is of great significance for reducing the complexity of programming algorithms and reducing calculation time.

[0070] Therefore, the Spherical t-designs integration method is used to design a spherical microphone array with a radius of a and a number of microphones M, and to obtain equal integral weight values ​​w for each point.

[0071] S2, reading the noise data collected in step S1, performing FFT processing on the noise data to obtain frequency domain sound pressure data, and using the frequency domain sound pressure data as input data of the sound field reconstruction algorithm;

[0072] S3, according to the input data obtained in step S2 combined with the spherical near-field acoustic holography method, calculate the approximate unknown coefficients

[0073] It should be noted that the sound field reconstruction is performed using the spherical near-field acoustic holography algorithm. The established model takes into account the sound wave scattering on the surface of the rigid sphere. The sound field reconstruction is corrected through the Neumann boundary condition, thereby improving the accuracy of the sound field reconstruction.

[0074] Specifically, the approximate unknown coefficients The acquisition logic is:

[0075] The three-dimensional closed space sound field reconstruction is realized based on the spherical near-field acoustic holography method. The sound field reconstruction theoretical formula is:

[0076]

[0077] Among them, P rec (r,θ,φ) represents the original incident wave acoustic field, represents the approximate unknown coefficient, j n (kr) represents the spherical Bessel function, represents spherical harmonics,;

[0078] When using a rigid sphere for sound field reconstruction, the scattered waves reflected by the sphere should be considered. The total sound pressure P on the rigid sphere is t It can be divided into the sound pressure P of the incident sound wave i and the sound pressure P of the scattered sound wave s as follows:

[0079] Total sound pressure: P t =P i +P s (1.2)

[0080] Incident wave sound pressure:

[0081] Scattered wave sound pressure:

[0082] where k is the wave number, j is n (kr) is the spherical Bessel function, h n (kr) is the spherical Hankel function, is a spherical harmonic function, A mn , C mn are the basis function coefficients;

[0083] When the normal particle velocity at the spherical surface of a rigid sphere array with a radius of a, that is, the gradient of the total sound pressure, is zero, the Neumann boundary condition for scattering on the rigid sphere can be expressed as follows:

[0084]

[0085] Among them, w t (a) represents the normal particle velocity on the rigid spherical surface,

[0086] Combining formula (1.5) with formula (1.3) and formula (1.4) yields:

[0087]

[0088] Formula (1.6) combined with formula (1.4), the scattered wave sound pressure can be expressed as:

[0089]

[0090] According to formula (1.7) combined with formula (1.2) and formula (1.3), the total sound pressure of the sound field can be obtained:

[0091]

[0092] The above formula (1.8) is the total sound field model established after scattering by the rigid surface sphere. According to formula (1.3) and formula (1.8), the incident wave sound pressure can be calculated;

[0093] Multiply formula (1.8) by the complex conjugate spherical harmonic function And integrate the entire sphere to obtain the unknown coefficient A mn , due to the sound pressure at the positions of a finite number of microphones on the spherical array, where the finite number is the number of microphones, the spherical numerical integration method is used to approximate the continuous integral on the entire sphere to calculate the approximate unknown coefficients

[0094]

[0095] S4, based on the approximate unknown coefficients Reconstruct the original incident sound field, and reconstruct the sound pressure distribution at any position in the spatial sound field around the spherical microphone array based on the original incident sound field, so as to identify the direction of the noise source;

[0096] Specifically, the original incident wave acoustic field is reconstructed according to formula (1.1) and formula (1.9):

[0097]

[0098] In the above formula, M represents the number of microphones, w iRepresents the corresponding weight of each microphone, N is the number of basis function cutoff terms, and the number of cutoff terms N and the number of microphones M need to satisfy (N+1) 2 ≤M, the optimal number of cutoff items corresponding to the number of M microphones is N opt .

[0099] The sound field reconstruction process includes steps such as noise data collection, FFT processing, calculation of undetermined coefficients, incident sound field reconstruction, and noise source location, ensuring the rigor and integrity of the entire reconstruction process. The supporting software has been designed and developed for data collection, signal processing and analysis, sound field reconstruction, and noise source visualization. It has a friendly human-computer interaction interface and improves the ease of use and operation of the system. The interface design between the software and the data acquisition hardware ensures accurate reading and effective processing of data, and can be applied to the calculation of sound pressure distribution in different target environment spaces, with high integration and compatibility.

[0100] Embodiment 3: For the parts not described in detail in this embodiment, please refer to Embodiments 1 and 2. This embodiment is described by taking an elevator car as an example. Figure 8 As shown, the sound pressure signal data is first collected through a rigid spherical array, and the spherical near-field acoustic holography method is combined to realize the reconstruction of the three-dimensional closed space sound field in the ultra-high-speed elevator car, and the noise source is visualized. In the process of reconstructing the sound field by combining the spherical microphone array with the spherical near-field acoustic holography, the designed rigid surface spherical microphone array is used as the measurement front end, and the sound pressure distribution at any position in the three-dimensional closed space is reconstructed by combining the spherical near-field acoustic holography method. The entire sound field reconstruction system consists of two parts: hardware and software. The rigid spherical array sphere is connected to the multi-channel signal acquisition instrument as the designed hardware to measure the sound field noise data. The mobile computer has a designed and developed software program. By designing the data interface between the multi-channel signal acquisition instrument and the software program, the software program controls the data acquisition process, which has the functions of synchronous acquisition and real-time display, and stores the data collected from each channel.

[0101] During the test, a rigid ball array device is placed at the geometric center of the ultra-high-speed elevator car. The height of the rigid ball array is adjusted so that the array is located at a measurement position at a certain height from the bottom of the car. The power supply and test leads are connected, the mobile computer is turned on, the sound field reconstruction software program is started, and the elevator start button is pressed to begin the sound field test.

[0102] At the same time, based on the current situation, we study theories and technologies such as rigid spherical scattering correction, microphone spherical distribution, spherical numerical integration, and spherical near-field acoustic holography. Considering the influence of factors such as array size, internal structure, and material on the accuracy of sound field reconstruction in the internal space of a three-dimensional closed structure, we study the sound field response measured by microphones arranged on the sphere, and use the spherical near-field acoustic holography method to reconstruct the sound field distribution in the three-dimensional closed space in the car, so as to achieve the purpose of accurately identifying and locating the noise source.

[0103] Embodiment 4: For the parts not described in detail in this embodiment, please refer to the description of Embodiment 2. This embodiment provides an electronic device, including: a processor and a memory, wherein the memory stores a computer program that can be called by the processor;

[0104] The processor executes the above-mentioned noise source location method by calling the computer program stored in the memory.

[0105] Embodiment 5: This embodiment provides a computer-readable storage medium storing instructions. When the instructions are executed on a computer, the computer executes the above-mentioned noise source location method.

[0106] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0107] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A noise source location method, characterized in that: The following steps are involved: S1. Place the rigid ball array sound field test device in the target environment and collect noise data; S2, reading the noise data collected in step S1, performing FFT processing on the noise data to obtain frequency domain sound pressure data, and using the frequency domain sound pressure data as input data of the sound field reconstruction algorithm; S3, calculating the approximate unknown coefficients according to the input data obtained in step S2 in combination with the spherical near-field acoustic holography method; S4. Reconstruct the original incident sound field according to the approximate unknown coefficients; reconstruct the sound pressure distribution at any position of the spatial sound field around the spherical microphone array according to the original incident sound field, so as to identify the direction of the noise source.

2. A noise source location method according to claim 1, characterized in that: The configuration information corresponding to the rigid spherical array sphere includes the array radius, the number of microphones, and the position distribution of each microphone. The position distribution of each microphone can also be described as a distribution of discrete points, which means that each microphone is used as a point for data collection; The logic for obtaining the configuration information corresponding to the rigid sphere array sphere is as follows: Based on the target environment, the center position of the environment is obtained, and the center position of the rigid sphere array is determined. Then the rigid sphere array is in the near field of the sound source, and the array radius is designed according to the spatial size of the target environment; The number of microphones and the distribution of discrete points are determined based on a spherical numerical integration method, wherein the microphones are symmetrically distributed on a sphere.

3. A noise source location method according to claim 2, characterized in that: The analysis logic of the geometric distribution and corresponding weights of the microphones on the rigid spherical array sphere includes: Configure a regular polyhedron whose center is the same as the center of the sphere, and adjust the size of the regular polyhedron so that its vertices are on the sphere. Then the positions of the vertices of this regular polyhedron are the distribution positions of the required discrete points on the sphere. Using different regular polyhedrons to perform symmetrical twisting about the rotation axis can also generate spherical optimization with a certain number of discrete points with different array radii; The spherical integral form is converted into the superposition of the values ​​at each discrete point to obtain the corresponding weight. Since each discrete point is spherically symmetric, it can be seen that the integral weights of these discrete integral points are equal.

4. A noise source location method according to claim 1, characterized in that: The sound field is reconstructed using the spherical near-field acoustic holography algorithm. The established model takes into account the sound wave scattering on the surface of the rigid sphere. The sound field reconstruction is corrected by the Neumann boundary condition, and the original incident sound pressure distribution at any position in the spatial sound field around the spherical microphone array is reconstructed to identify the direction of the noise source.

5. A noise source location method according to claim 4, characterized in that: Supporting software was designed and developed for data acquisition, signal processing and analysis, sound field reconstruction and noise source visualization positioning, and the noise source visualization positioning results were displayed on the human-computer interaction interface.

6. A rigid ball array sound field testing device, based on the implementation of a noise source localization method according to any one of claims 1 to 6, characterized in that: It comprises a rigid ball array sphere, which is fixed on a base (5) via a telescopic connecting tube (3); The rigid spherical array sphere is provided with microphone channels adapted to the microphones uniformly arranged on the spherical surface according to the spherical numerical integration method; one end of the microphone with the microphone is exposed on the outer surface of the rigid spherical array sphere and is flush with the outer surface of the rigid spherical array sphere; the other end of the microphone is inside the rigid spherical array sphere and is connected to a wire; a large hole (2-5) is provided at the bottom of the rigid spherical array sphere for inserting one end of a telescopic connecting tube (3); the other end of the telescopic connecting tube (3) is inserted into a mounting hole (5-1) on a base (5); the wire is connected to a signal acquisition instrument in the inner cavity of the base (5) based on the mounting hole (5-1); and the signal acquisition instrument is connected to an electronic device at a free position on the outer surface of the base (5).

7. The rigid ball array sound field testing device according to claim 6, characterized in that: The rigid ball array sphere comprises a rigid ball array upper hemisphere (1) and a rigid ball array lower hemisphere (2); the rigid ball array upper hemisphere (1) and the rigid ball array lower hemisphere (2) are fixedly connected, and microphone channels are arranged on the rigid ball array upper hemisphere (1) and the rigid ball array lower hemisphere (2).

8. The rigid ball array sound field testing device according to claim 7, characterized in that: The telescopic connecting tube (3) is fixed by a clamp (4), and the clamp (4) comprises a clamp hole (4-1) for fixing the telescopic connecting tube (3), and the clamp hole (4-1) is tightened or loosened by a threaded knob (4-2).

9. An electronic device, comprising: A processor and a memory, wherein the memory stores a computer program that can be called by the processor; The processor executes the noise source localization method according to any one of claims 1 to 5 by calling the computer program stored in the memory.

10. A computer-readable storage medium storing instructions, which, when executed on a computer, enables the computer to execute the noise source localization method according to any one of claims 1 to 5.

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