Acoustic emission positioning method and device for structural damage of composite material

Abstract

The invention provides an acoustic emission positioning method and device for structural damage of a composite material. The method comprises the following steps: acquiring an acoustic emission signal to be positioned; performing preliminary positioning on the acoustic emission signal to obtain an initial positioning coordinate and an initial moment of the acoustic emission signal; taking the initial positioning coordinate and the initial moment as initial quantities of an optimization model, taking an acoustic emission source as an unknown quantity, taking the variable quantity of group velocity along with the angle as a known quantity, substituting the quantities into the optimization model for iterative calculation, and correcting the position of the acoustic emission source to obtain a global optimal solution of the optimization model; and taking the global optimal solution as a positioning result of the acoustic emission source. According to the method, acoustic emission signals are collected and analyzed through acoustic emission, so that the damage position of the composite material is identified and positioned, the positioning accuracy of the damage position of the composite material is improved, and the positioning difficulty is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of nondestructive material testing, and in particular to an acoustic emission positioning method and device for composite material structure damage. Background Art

[0002] Composite materials, as a new type of material composed of two or more special materials, play an important role in various fields such as aerospace, civil engineering and automobile manufacturing with their excellent properties such as high strength, high stiffness, light weight and corrosion resistance. Because of the unique advantages of composite materials, they are usually used in harsh and complex working environments, which makes composite structures face huge challenges during long-term service. Therefore, the non-destructive testing technology of detecting defects in composite materials using the acoustic emission source positioning method is one of the important technical means to achieve long-term reliable operation of composite structures.

[0003] In the existing technology, the composite material source positioning method based on acoustic emission mainly solves the equation group to obtain the position of the sound source based on the constant wave velocity assumption, but the error is large and there are certain limitations. In order to overcome the shortcomings of the triangulation positioning method, the position estimate of the damage source can be obtained by minimizing the error function. Using more sensors can obtain more accurate positioning results, but it will also increase the complexity of the error function and the calculation time.

[0004] However, the constant wave velocity assumption is not applicable to the detection of composite material structures. At the same time, the starting time of the acoustic emission source is also unknown during the actual monitoring process. Since the method for obtaining the starting time is mainly to solve the equation, the different propagation speeds of composite materials often lead to an unsolvable set of equations. This leads to the problem of difficulty in locating the acoustic emission source in the composite material and poor positioning accuracy.

[0005] In view of this, the present invention provides an acoustic emission positioning method and device for composite material structure damage, so as to solve the technical problems in the prior art that the positioning of composite material damage is difficult and the positioning accuracy is poor. Summary of the invention

[0006] The present invention provides an acoustic emission positioning method and device for composite material structure damage, which collects and analyzes acoustic emission signals through acoustic emission, thereby realizing identification and positioning of composite material damage positions, thereby improving the positioning accuracy of composite material damage positions and reducing the positioning difficulty.

[0007] The present invention provides an acoustic emission positioning method for composite material structure damage, the method comprising:

[0008] Acquiring an acoustic emission signal to be located;

[0009] Preliminarily positioning the acoustic emission signal to obtain initial positioning coordinates and an initial time of the acoustic emission signal;

[0010] The initial positioning coordinates and the initial time are used as the initial quantities of the optimization model, the acoustic emission source is used as the unknown quantity, and the relationship between the group velocity of the optimization model and the angle is used as the known quantity for iterative calculation to obtain the global optimal solution of the optimization model, and the global optimal solution is used as the positioning result of the acoustic emission source.

[0011] In some embodiments, performing preliminary positioning on the acoustic emission signal to obtain initial positioning coordinates specifically includes:

[0012] extracting a single modal component from the acoustic emission signal;

[0013] Performing time reversal processing on the single modal component to obtain a time reversal signal;

[0014] Delaying the time-reversed signal based on the theoretical arrival time, and superimposing the signals obtained after the delay processing to obtain a superimposed signal curve at each grid pre-divided on the target composite material;

[0015] Generating a pixel matrix based on the superimposed signal curve, and generating a pixel distribution map of the target composite material using the pixel matrix;

[0016] The coordinate position of the maximum pixel value in the pixel distribution map is extracted, and the coordinate position is used as the initial positioning coordinate.

[0017] In some embodiments, the optimization model is one of a Geiger algorithm model, a genetic algorithm model, and a particle swarm optimization algorithm model.

[0018] In some embodiments, the optimization model is an improved Geiger algorithm model, and calculating the global optimal solution of the swarm optimization model specifically includes:

[0019] Obtain the relationship between the group velocity of the acoustic emission signal in the target composite material and the angle;

[0020] The improved Geiger algorithm model is used to iteratively update the acoustic emission source location coordinates until the global optimal solution is obtained and the iteration is stopped.

[0021] In some embodiments, obtaining the relationship between the group velocity of the acoustic emission signal in the target composite material and the angle thereof specifically includes:

[0022] Setting a target excitation point on a target composite material;

[0023] Within a preset angle range, the acoustic wave signals at two concentric circles of the acoustic emission source are respectively acquired with a fixed step length as an increment to obtain the variation of the group velocity of the target composite material within the preset angle range with the angle.

[0024] In some embodiments, the improved Geiger algorithm model is used to iteratively update the acoustic emission source location coordinates, specifically including:

[0025] Taking the acoustic emission source information as the unknown quantity, for an array composed of several acoustic emission receiving sensors, the relationship between the group velocity and the angle is obtained;

[0026] The relationship between the group velocity and the angle is used as a known quantity to iteratively update the emission source information until the global optimal solution is obtained and the iteration is stopped.

[0027] The present invention also provides an acoustic emission positioning device for composite material structure damage, the device comprising:

[0028] A signal acquisition unit, used to acquire the acoustic emission signal to be located;

[0029] An initial positioning unit, used to perform preliminary positioning of the acoustic emission signal to obtain initial positioning coordinates and an initial time of the acoustic emission signal;

[0030] The result optimization unit is used to use the initial positioning coordinates and the initial time as the initial quantities of the optimization model, the acoustic emission source as the unknown quantity, and the relationship between the group velocity of the optimization model and the angle as the known quantity for iterative calculation to obtain the global optimal solution of the optimization model, and use the global optimal solution as the positioning result of the acoustic emission source.

[0031] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method described above when executing the program.

[0032] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the method described above when executed by a processor.

[0033] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the method described above is implemented.

[0034] The acoustic emission positioning method and device for composite material structure damage provided by the present invention obtains the acoustic emission signal to be positioned; performs preliminary positioning on the acoustic emission signal to obtain the initial positioning coordinates and the initial time of the acoustic emission signal; uses the initial positioning coordinates and the initial time as the initial quantity of the optimization model, uses the acoustic emission source as the unknown quantity, and uses the relationship between the group velocity and the angle of the group optimization model as the known quantity for iterative calculation to obtain the global optimal solution of the optimization model, and uses the global optimal solution as the positioning result of the acoustic emission source. In this way, the method and device can effectively solve the problem that the constant wave velocity assumption is not applicable in the positioning of the acoustic emission source of the composite material structure, realizes the effective positioning of the acoustic emission source in the composite material, collects and analyzes the acoustic emission signal through acoustic emission, solves the technical problems of the high difficulty in positioning the damage position of the composite material and the poor positioning accuracy in the prior art, improves the positioning accuracy of the damage position in the composite material, and reduces its positioning difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 One of the flow charts of the acoustic emission positioning method for composite material structure damage provided by the present invention;

[0037] Figure 2 A hardware schematic diagram of the positioning system provided by the present invention;

[0038] Figure 3 The second flowchart of the acoustic emission positioning method for composite material structure damage provided by the present invention;

[0039] Figure 4 Flow chart 3 of the acoustic emission positioning method for composite material structure damage provided by the present invention;

[0040] Figure 5 A schematic diagram of the receiving sensor position for obtaining the acoustic emission signal wave velocity angle function in a specific usage scenario;

[0041] Figure 6 It is the superimposed signal curve of four acoustic emission receiving sensors at the initial positioning coordinates in a specific usage scenario;

[0042] Figure 7 This is the preliminary positioning result of four excitation points in a specific usage scenario;

[0043] Figure 8It is an overall flow chart in a specific usage scenario;

[0044] Fig. 9 A schematic diagram of the structure of an acoustic emission positioning device for composite material structural damage provided by the present invention;

[0045] Fig.10 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are 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.

[0047] In order to solve the problems existing in the prior art, the present invention provides an acoustic emission positioning method for composite material structure damage, which is a composite material acoustic emission source positioning method that takes into account the change in wave velocity. First, the time reversal focusing method is used for preliminary positioning to obtain preliminary positioning coordinates, and the start time of the acoustic emission signal is obtained by obtaining the superimposed signal curve of the preliminary positioning position; then the obtained preliminary positioning coordinates and the start time of the acoustic emission signal are input into the improved Geiger iteration process, the acoustic emission source information is updated, and the accurate positioning of the acoustic emission source is achieved. The method and device provided by the present invention can effectively solve the problem that the constant wave velocity assumption is not applicable in the positioning of the acoustic emission source of the composite material structure, and has important practical application value.

[0048] The acoustic emission positioning method for composite material structure damage provided by the present invention needs to rely on the positioning system as hardware support, such as Figure 2 As shown, the positioning system includes a waveform generator 1, a composite material plate 2 (i.e., a composite material to be detected), an acoustic emission sensor 3 (including an acoustic emission excitation sensor and an acoustic emission receiving sensor), a preamplifier 4 and an acoustic emission monitoring system (including an analyzer 5 and a computer 6), wherein the waveform generator is connected to the acoustic emission excitation sensor and is arranged on the composite material plate, and the acoustic emission receiving sensors are evenly arranged on the composite material plate, and the acoustic emission receiving sensors are all connected to preamplifiers in turn, and the preamplifiers are connected to the acoustic emission detection system.

[0049] Please refer to Figure 1 , Figure 1 This is one of the flow charts of the acoustic emission positioning method for composite material structure damage provided by the present invention.

[0050] In a specific embodiment, the acoustic emission localization method for composite material structure damage provided by the present invention comprises the following steps:

[0051] S110: Acquire an acoustic emission signal to be located;

[0052] S120: Preliminarily positioning the acoustic emission signal to obtain initial positioning coordinates and an initial time of the acoustic emission signal;

[0053] S130: The initial positioning coordinates and the initial time are used as the initial quantities of the optimization model, the acoustic emission source is used as the unknown quantity, and the relationship between the group velocity of the optimization model and the angle is used as the known quantity for iterative calculation to obtain the global optimal solution of the optimization model, and the global optimal solution is used as the positioning result of the acoustic emission source. It should be understood that the position of the acoustic emission source is also the position of the defect in the composite material.

[0054] In S120, the acoustic emission signal is initially positioned to obtain initial positioning coordinates, such as Figure 3 As shown, the specific steps include:

[0055] S310: extracting a single modal component from the acoustic emission signal; in a specific usage scenario, extracting the S0 mode from the acoustic emission signal, using wavelet transform on the acoustic emission signal acquired by the acoustic emission receiving sensor, extracting and reconstructing the S0 modal component from the acoustic emission signal;

[0056] S320: performing time reversal processing on the single modal component to obtain a time reversal signal; in the above scenario, the S0 modal component of the acoustic emission signal is time reversed, a sufficiently long time window is taken, the S0 modal component signal within the time window is time reversed and normalized to obtain a time reverse signal;

[0057] S330: delaying the time-reversed signal based on the theoretical arrival time, and superimposing the signals obtained after the delay processing to obtain a superimposed signal curve at each grid pre-divided on the target composite material; specifically, when delaying and superimposing the signal, the composite material plate is divided into a plurality of grids M×N, the theoretical arrival time is calculated according to the Euclidean distance from each grid to the acoustic emission receiving sensor, the time-reversed signal is delayed according to the theoretical arrival time, and the delayed signals are superimposed to obtain a superimposed signal curve at each grid;

[0058] S340: Generate a pixel matrix based on the superimposed signal curve, and use the pixel matrix to generate a pixel distribution map of the target composite material; in the process of generating the pixel distribution map of the composite material plate, first obtain the maximum value of the superimposed signal curve at each grid in S330, generate a pixel matrix Obtaining a pixel distribution map within the composite material plate;

[0059] S350: extracting the coordinate position of the maximum pixel value in the pixel distribution map, and using the coordinate position as the initial positioning coordinate; that is, the point with the maximum pixel value in the pixel distribution map is the initial positioning coordinate obtained by preliminary positioning.

[0060] Theoretically, the optimization model can be one of the Geiger algorithm model, genetic algorithm model, and particle swarm optimization algorithm model. The optimization model is a mathematical theory and method that seeks to reasonably allocate limited resources to maximize (or minimize) one or more indicators of interest under a series of objective or subjective constraints. It is a very important branch of operations research. In this embodiment, the optimization model can be a Geiger algorithm model. The method used in the present invention uses the improved Geiger algorithm model to calculate the global optimal solution of the optimization model, such as Figure 4 As shown, the specific steps include:

[0061] S410: Obtain the relationship between the group velocity of the acoustic emission signal in the target composite material and the angle; specifically, set a target excitation point on the target composite material, and obtain the acoustic wave signals at two concentric circles of the acoustic emission source within a preset angle range with a fixed step size as an increment, so as to obtain the amount of change of the group velocity of the target composite material within the preset angle range with the angle. For example, when measuring the group velocity of the acoustic emission signal in a composite material plate, set an excitation point on the composite material plate, and place an acoustic emission receiving sensor at two concentric circles of the acoustic emission source within a range of 0° to 90° with a fixed step size as an increment, and then obtain the change of the group velocity within the range of 0° to 90° in the composite material plate with the angle, and the expression is:

[0062] v g (θ)=f(θ) (1)

[0063] Among them, v g (θ) represents the change of group velocity in the composite plate with angle, g represents the group velocity, θ represents the angle between the line connecting the two sensors and the horizontal positive direction, and f(θ) represents the relationship between the group velocity in the composite plate and the angle.

[0064] S420: using the improved Geiger algorithm model to iteratively update the acoustic emission source positioning coordinates until the global optimal solution is obtained and the iteration is stopped; specifically, taking the acoustic emission source information as an unknown quantity, for an array composed of a number of acoustic emission receiving sensors, the relationship between the group velocity and the angle is obtained; taking the relationship between the group velocity and the angle as a known quantity, iteratively update the emission source information until the global optimal solution is obtained and the iteration is stopped.

[0065] Furthermore, for an array composed of a plurality of acoustic emission receiving sensors, the following conditions are satisfied:

[0066]

[0067] Among them, v g represents the group velocity from the sound source to the i-th sensor, t i represents the time when the ith sensor receives the acoustic emission signal, t0 represents the starting time of the acoustic emission event, x represents the horizontal coordinate of the acoustic emission source position, and x i represents the horizontal coordinate of the i-th sensor, y represents the vertical coordinate of the acoustic emission source position, and y i Represents the vertical coordinate of the i-th sensor.

[0068] The acoustic emission source information α(x, y, t0) is taken as the unknown quantity, and the t i Taylor expansion is performed and simplifies to:

[0069]

[0070] Among them, α represents a row vector containing the information of the acoustic emission source, Indicates t i The partial derivative of x, that is, the partial derivative of the abscissa of the sound source position at the moment when the i-th sensor receives the acoustic emission signal; Indicates t i The partial derivative of y, that is, the partial derivative of the ordinate of the sound source position at the moment when the i-th sensor receives the acoustic emission signal; Indicates t i The partial derivative with respect to t, that is, the partial derivative of the moment when the i-th sensor receives the acoustic emission signal with respect to the arrival time of the sensor receiving the signal, Δx represents the correction amount of the horizontal coordinate of the sound source position, Δy represents the correction amount of the vertical coordinate of the sound source position, and Δt represents the correction amount when the sensor receives the acoustic signal.

[0071] Where:

[0072]

[0073] In formula (3), Ri is the Peano remainder, which is a high-order infinitesimal term of order 2 or above.

[0074] Ignore Ri and transform equation (3) into matrix form:

[0075] QΔβ=T (4)

[0076] Among them, Q represents the Taylor expansion matrix, Δβ represents the sound source position correction matrix, and T represents the time matrix. The specific expression is:

[0077]

[0078] The solution is:

[0079] Δβ=(Q T Q) -1 Q T T (5)

[0080] The Geiger iteration process uses Δβ as the correction value to continuously update the acoustic emission source information:

[0081] α i =α i-1 +Δβ (6)

[0082] Among them, α i is the acoustic emission source information obtained in the i-th iteration, α i-1 is the acoustic emission source information obtained in the i-1th iteration.

[0083] In the improved Geiger iteration process, the obtained group velocity variation with angle is brought into the above Geiger iteration process, and the Q matrix in the rth iteration process is:

[0084] Q r =Q r-1 ⊙V r (7)

[0085] Where V represents the group velocity iteration matrix, represents the element in the i-th row and j-th column of the Q matrix, and * represents the multiplication of the corresponding elements of the matrix. represents the element in the i-th row and j-th column of the V matrix, ⊙ is the Hadamard product operation; the rest of the steps are the same as the traditional Geiger iterative process.

[0086] Through updating and iteration, the final global optimal solution can be considered as the location of the acoustic emission source. The change of velocity with angle is taken into account in the improved Geiger iteration process. The acoustic emission source information is updated through the improved iterative correction process, which effectively solves the problem of the inapplicability of the constant wave velocity assumption in the localization of acoustic emission sources of composite materials, and the positioning performance is significantly improved.

[0087] For ease of understanding, the implementation process and technical effects of the method provided by the present invention are briefly described below using a specific usage scenario as an example.

[0088] like Figure 5-8As shown in the figure, a carbon fiber reinforced epoxy resin-based composite material plate is selected, 700mm×700mm×3mm, the number of layers is 16, the single layer thickness is 0.1875mm, and the ply direction is [-45 / 0 / 45 / 90]. Four acoustic emission receiving sensors are evenly set on the carbon fiber reinforced epoxy resin-based composite material plate, and the array coordinates of the acoustic emission receiving sensors are (550mm, 350mm), (350mm, 550mm), (150mm, 350mm) and (350mm, 150mm) respectively. The experiment uses a signal generator to use a Sinker pulse with a center frequency of 150kHz as the excitation source, and the sampling frequency is 3MHz.

[0089] Step 1: Use wavelet transform to extract and reconstruct the S0 modal component of the acoustic emission signal obtained by the four acoustic emission receiving sensors;

[0090] Step 2: Take a sufficiently long time window, and simultaneously perform time-reversal processing on the S0 modal component signals of the four acoustic emission receiving sensors within the time window and normalize them to obtain a time-reversed signal;

[0091] Step 3: Divide the carbon fiber reinforced epoxy resin-based composite material plate into a number of grids of 700×700, calculate the theoretical arrival time according to the Euclidean distance from each grid to the four acoustic emission receiving sensors, reverse the signal delay according to the theoretical arrival time, and superimpose the delayed signals to obtain the superimposed signal curve at each grid;

[0092] Step 4: Obtain the maximum value of the superimposed signal curve at each grid in step 3, generate a pixel matrix, and obtain a pixel distribution map of the carbon fiber reinforced epoxy resin-based composite material plate. The location with the maximum pixel value is the preliminary positioning coordinate. At the preliminary positioning coordinate, the S0 modes on the superimposed signal curves of the four acoustic emission sensors almost overlap, the maximum value on the superimposed signal curve is close to 4, and the distance between the maximum value and the right time window is the acoustic emission start time t0;

[0093] Step 5: Take (150mm, 150mm) as the excitation point, draw concentric circles with radii of 100mm and 400mm, place acoustic emission receiving sensors at two concentric circles of the acoustic emission source in the range of 0° to 90° with an increment of 15°, and obtain the change of group velocity with angle in the range of 0° to 90° in the composite plate;

[0094] Step 6: Use the preliminary positioning coordinates obtained in step 4 as the initial iteration point, and use the change of group velocity with angle obtained in step 5 as prior knowledge, and bring them into the improved Geiger iteration process to obtain the global optimal solution by updating the A matrix and correcting the α vector in the iteration.

[0095] The deviation between the calculated position and the theoretical position is defined as:

[0096]

[0097] Wherein, △R is the absolute error, S is the maximum sensor spacing in the sensor array, and 10 excitation points are located using the triangulation positioning method and the positioning method provided by the present invention (the triangulation positioning method is used as a comparative example), respectively. The positioning result comparison table is shown in Table 1.

[0098] Table 1 Comparison of positioning results

[0099]

[0100] In the above specific implementation, the acoustic emission positioning method for composite material structure damage provided by the present invention obtains the acoustic emission signal to be positioned; performs preliminary positioning on the acoustic emission signal to obtain the initial positioning coordinates and the initial time of the acoustic emission signal; uses the initial positioning coordinates and the initial time as the initial quantity of the optimization model, uses the acoustic emission source as an unknown quantity, and uses the relationship between the group velocity of the optimization model and the angle as a known quantity for iterative calculation to obtain the global optimal solution of the optimization model, and uses the global optimal solution as the positioning result of the acoustic emission source. In this way, the method can effectively solve the problem that the constant wave velocity assumption is not applicable in the positioning of the acoustic emission source of the composite material structure, realizes the effective positioning of the acoustic emission source in the composite material, collects and analyzes the acoustic emission signal through acoustic emission, solves the technical problems of the difficulty of positioning the damage position of the composite material in the prior art and the poor positioning accuracy, improves the positioning accuracy of the damage position in the composite material, and reduces its positioning difficulty.

[0101] In addition to the above method, the present invention also provides an acoustic emission positioning device for composite material structure damage, such as Fig. 9 As shown, the device comprises:

[0102] A signal acquisition unit 910 is used to acquire an acoustic emission signal to be located;

[0103] An initial positioning unit 920, used to perform preliminary positioning of the acoustic emission signal to obtain initial positioning coordinates and an initial time of the acoustic emission signal;

[0104] The result optimization unit 930 is used to iteratively calculate the initial positioning coordinates and the initial time as the initial quantities of the optimization model, the acoustic emission source as the unknown quantity, and the relationship between the group velocity of the optimization model and the angle as the known quantity to obtain the global optimal solution of the optimization model, and use the global optimal solution as the positioning result of the acoustic emission source.

[0105] In some embodiments, performing preliminary positioning on the acoustic emission signal to obtain initial positioning coordinates specifically includes:

[0106] extracting a single modal component from the acoustic emission signal;

[0107] Performing time reversal processing on the single modal component to obtain a time reversal signal;

[0108] Delaying the time-reversed signal based on the theoretical arrival time, and superimposing the signals obtained after the delay processing to obtain a superimposed signal curve at each grid pre-divided on the target composite material;

[0109] Generating a pixel matrix based on the superimposed signal curve, and generating a pixel distribution map of the target composite material using the pixel matrix;

[0110] The coordinate position of the maximum pixel value in the pixel distribution map is extracted, and the coordinate position is used as the initial positioning coordinate.

[0111] In some embodiments, the optimization model is one of a Geiger algorithm model, a genetic algorithm model, and a particle swarm optimization algorithm model.

[0112] In some embodiments, the volume optimization model is an improved Geiger algorithm model, and calculating the global optimal solution of the optimization model specifically includes:

[0113] Obtain the relationship between the group velocity of the acoustic emission signal in the target composite material and the angle;

[0114] The improved Geiger algorithm model is used to iteratively update the acoustic emission source location coordinates until the global optimal solution is obtained and the iteration is stopped.

[0115] In some embodiments, obtaining the relationship between the group velocity of the acoustic emission signal in the target composite material and the angle thereof specifically includes:

[0116] Setting a target excitation point on a target composite material;

[0117] Within a preset angle range, the acoustic wave signals at two concentric circles of the acoustic emission source are respectively acquired with a fixed step length as an increment to obtain the variation of the group velocity of the target composite material within the preset angle range with the angle.

[0118] In some embodiments, the improved Geiger algorithm model is used to iteratively update the acoustic emission source location coordinates, specifically including:

[0119] Taking the acoustic emission source information as the unknown quantity, for an array composed of several acoustic emission receiving sensors, the relationship between the group velocity and the angle is obtained;

[0120] The relationship between the group velocity and the angle is used as a known quantity to iteratively update the emission source information until the global optimal solution is obtained and the iteration is stopped.

[0121] In the above specific embodiments, the composite source positioning device based on acoustic emission provided by the present invention obtains the acoustic emission signal to be positioned; performs preliminary positioning on the acoustic emission signal to obtain the initial positioning coordinates and the initial time of the acoustic emission signal; uses the initial positioning coordinates and the initial time as the initial quantity of the optimization model, uses the acoustic emission source as an unknown quantity, and uses the relationship between the group velocity of the optimization model and the angle as a known quantity for iterative calculation to obtain the global optimal solution of the optimization model, and uses the global optimal solution as the positioning result of the acoustic emission source. In this way, the method and device can effectively solve the problem that the constant wave velocity assumption is not applicable in the positioning of the acoustic emission source of the composite structure, realizes the effective positioning of the acoustic emission source in the composite material, realizes the effective positioning of the acoustic emission source in the composite material, collects and analyzes the acoustic emission signal through acoustic emission, solves the technical problems of the difficulty of locating the damaged position of the composite material and the poor positioning accuracy in the prior art, improves the positioning accuracy of the damaged position in the composite material, and reduces its positioning difficulty.

[0122] Fig.10 An example of a physical structure diagram of an electronic device is shown in FIG. Fig.10 As shown, the electronic device may include: a processor 1010, a communication interface 1020, a memory 1030 and a communication bus 1040, wherein the processor 1010, the communication interface 1020 and the memory 1030 communicate with each other through the communication bus 1040. The processor 1010 may call the logic instructions in the memory 1030 to execute the above method.

[0123] In addition, the logic instructions in the above-mentioned memory 1030 can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on such an understanding, the part of the technical solution of the present invention that essentially contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instruction sets that enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0124] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can perform the above method.

[0125] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0126] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0127] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An acoustic emission location method for composite material structure damage, It is characterized in that The method comprises: Acquiring an acoustic emission signal to be located; Preliminarily positioning the acoustic emission signal to obtain initial positioning coordinates and an initial time of the acoustic emission signal; The initial positioning coordinates and the initial time are used as the initial quantities of the optimization model, the acoustic emission source is used as the unknown quantity, and the change of the group velocity with the angle is used as the known quantity to be brought into the optimization model for iterative calculation to obtain the global optimal solution of the optimization model, and the global optimal solution is used as the positioning result of the acoustic emission source.

2. The acoustic emission positioning method for composite material structure damage according to claim 1, It is characterized in that Preliminary positioning of the acoustic emission signal to obtain initial positioning coordinates specifically includes: extracting a single modal component from the acoustic emission signal; Performing time reversal processing on the single modal component to obtain a time reversal signal; Delaying the time-reversed signal based on the theoretical arrival time, and superimposing the signals obtained after the delay processing to obtain a superimposed signal curve at each grid pre-divided on the target composite material; Generating a pixel matrix based on the superimposed signal curve, and generating a pixel distribution map of the target composite material using the pixel matrix; The coordinate position of the maximum pixel value in the pixel distribution map is extracted, and the coordinate position is used as the initial positioning coordinate.

3. The acoustic emission positioning method for composite material structure damage according to claim 1 or 2, It is characterized in that The optimization model is one of a Geiger algorithm model, a genetic model, a particle swarm optimization algorithm model and an ant colony optimization algorithm model.

4. The acoustic emission positioning method for composite material structure damage according to claim 3, It is characterized in that The optimization model is an improved Geiger algorithm model, and calculating the global optimal solution of the optimization model specifically includes: Obtain the relationship between the group velocity of the acoustic emission signal in the target composite material and the angle; The improved Geiger algorithm model is used to iteratively update the acoustic emission source location coordinates until the global optimal solution is obtained and the iteration is stopped.

5. The acoustic emission positioning method for composite material structure damage according to claim 1, It is characterized in that Obtain the relationship between the group velocity of the acoustic emission signal in the target composite material and the angle, including: Setting a target excitation point on a target composite material; Within a preset angle range, the acoustic wave signals at two concentric circles of the acoustic emission source are respectively acquired with a fixed step length as an increment to obtain the relationship between the group velocity and the angle of the target composite material within the preset angle range.

6. The acoustic emission positioning method for composite material structure damage according to claim 1, It is characterized in that The improved Geiger algorithm model is used to iteratively update the acoustic emission source location coordinates, including: Taking the acoustic emission source information as the unknown quantity, for an array composed of several acoustic emission receiving sensors, the relationship between the group velocity and the angle is obtained; The relationship between the group velocity and the angle is used as a known quantity and introduced into the model. The emission source information is updated iteratively until the global optimal solution is obtained and the iteration is stopped.

7. An acoustic emission positioning device for composite material structure damage, It is characterized in that The device comprises: A signal acquisition unit, used to acquire the acoustic emission signal to be located; An initial positioning unit, used to perform preliminary positioning of the acoustic emission signal to obtain initial positioning coordinates and an initial time of the acoustic emission signal; The result optimization unit is used to use the initial positioning coordinates and the initial time as the initial quantities of the optimization model, the acoustic emission source as the unknown quantity, and the relationship between the group velocity of the optimization model and the angle as the known quantity for iterative calculation to obtain the global optimal solution of the optimization model, and use the global optimal solution as the positioning result of the acoustic emission source.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, It is characterized in that When the processor executes the program, the method according to any one of claims 1 to 6 is implemented.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, It is characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

10. A computer program product comprising a computer program, It is characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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