An aircraft structure damage identification method, system, device and computer medium

Abstract

The application discloses an aircraft structure damage identification method, system, device and computer medium, and relates to the technical field of aircrafts. A target model of a structure to be identified in an aircraft is acquired. A target stiffness distribution information field of the target model is generated based on radial basis function interpolation. Coefficients of radial basis function nodes in the target stiffness distribution information field are changed to simulate damage, and a strain change amount before and after the radial basis function nodes are changed is generated as a reference strain change amount. An actual measured strain change amount of the structure to be identified is acquired. A target radial basis function node is determined according to the similarity between the actual measured strain change amount and the reference strain change amount. A damage position of the structure to be identified is determined based on a position corresponding to the target radial basis function node. A damage degree of the structure to be identified is determined based on the identified damage position. Damage identification is realized through radial basis function interpolation and strain change amount, damage identification accuracy is improved, and the method is low in cost and easy to popularize.

Description

Technical Field

[0001] This application relates to the field of aircraft technology, and more specifically, to a method, system, device, and computer medium for identifying structural damage to aircraft. Background Technology

[0002] The structural strength of an aircraft is a factor affecting flight safety and flight quality. Currently, the demands for lightweight structural design, the promotion of new materials and structures, mechatronics design, and the diversification of mission types and service scenarios will inevitably place higher requirements on the design level of structural safety.

[0003] Online structural damage identification utilizes sensor networks and signal processing methods for real-time assessment of structural conditions, ensuring the safety of aircraft structures. For example, the location of damage within the structure can be obtained by processing ultrasonic guided wave signals, and the degree of structural damage can be identified based on model correction methods using strain or modal information.

[0004] However, guided waves are ultrasonic signals transmitted inside the structure. They are sensitive to external forces and thermal loads and are easily interfered with by external forces and thermal loads, resulting in inaccurate damage identification results based on guided waves. In addition, they have high requirements for hardware and are difficult to promote in engineering.

[0005] In conclusion, how to accurately identify structural damage to aircraft while reducing hardware requirements is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] The purpose of this application is to provide a method for identifying structural damage in aircraft, which can, to some extent, solve the technical problem of accurately identifying structural damage in aircraft while reducing hardware requirements. This application also provides an aircraft structural damage identification system, electronic equipment, and a computer-readable storage medium.

[0007] To achieve the above objectives, this application provides the following technical solution:

[0008] A method for identifying structural damage to aircraft includes:

[0009] Obtain the target model of the structure to be identified in the aircraft;

[0010] Based on radial basis function interpolation, the target stiffness distribution information field of the target model is generated;

[0011] The coefficients of the radial basis function nodes in the target stiffness distribution information field are changed to simulate damage, and the strain change before and after changing the radial basis function nodes is generated as a reference strain change.

[0012] Obtain the measured strain change of the structure to be identified;

[0013] The target radial basis function nodes are determined based on the similarity between the measured strain change and the reference strain change.

[0014] The damage location of the structure to be identified is determined based on the position corresponding to the target radial basis function node;

[0015] Based on the location of the damage, the degree of damage to the structure to be identified is determined.

[0016] Preferably, generating the target stiffness distribution information field of the target model based on radial basis function interpolation includes:

[0017] Stiffness reduction information is generated based on radial basis function interpolation;

[0018] Based on the stiffness reduction information, an initial stiffness distribution information field is generated;

[0019] The initial stiffness distribution information field is mapped to the target model using the Gaussian integral method to generate the target stiffness distribution information field of the target model.

[0020] Preferably, the step of changing the coefficients of the radial basis function nodes in the target stiffness distribution information and generating the strain change before and after changing the radial basis function nodes as a reference strain change includes:

[0021] The coefficients of each radial basis function node in the target stiffness distribution information are changed sequentially, and the simulated strain change before and after changing the radial basis function nodes is generated through parametric simulation.

[0022] The simulated strain change is used as the reference strain change for the radial basis function node.

[0023] Preferably, determining the target radial basis function node based on the similarity between the measured strain change and the reference strain change includes:

[0024] Generate the cosine similarity value between the measured strain change and each of the reference strain changes;

[0025] The reference strain change corresponding to the highest cosine similarity value is used as the candidate strain change.

[0026] The radial basis function nodes corresponding to the candidate strain changes are used as the target radial basis function nodes.

[0027] Preferably, generating the cosine similarity value between the measured strain change and each of the reference strain changes includes:

[0028] The measured strain change is normalized to obtain the first normalized value;

[0029] The reference strain change is normalized to obtain a second normalized value;

[0030] Generate cosine similarity values ​​between the first normalized value and each of the second normalized values.

[0031] Preferably, determining the degree of damage to the structure to be identified based on the damage location includes:

[0032] Obtain the strain value after changing the radial basis function nodes as the reference strain value;

[0033] Obtain the measured strain value of the structure to be identified;

[0034] Based on the reference strain value and the measured strain value, a damage degree quantification model is generated at the damage location;

[0035] Based on radial basis function interpolation, the stiffness reduction factor at the damage location is generated;

[0036] Based on the stiffness reduction factor, the damage degree quantification model is processed to generate the radial basis function nodal coefficients at the damage location;

[0037] The degree of damage at the damage location is determined based on the radial basis function node coefficients at the damage location.

[0038] Preferably, the step of processing the damage quantification model to generate the radial basis function nodal coefficients at the damage location includes:

[0039] The damage quantification model is processed by a pattern search method to generate the radial basis function node coefficients at the damage location.

[0040] An aircraft structural damage identification system, comprising:

[0041] The model acquisition module is used to acquire the target model of the structure to be identified in the aircraft;

[0042] The stiffness distribution generation module is used to generate the target stiffness distribution information field of the target model based on radial basis function interpolation.

[0043] The damage simulation module is used to change the coefficients of the radial basis function nodes in the target stiffness distribution information field to simulate damage, and to generate the strain change before and after changing the radial basis function nodes as a reference strain change.

[0044] The measured strain change acquisition module is used to acquire the measured strain change of the structure to be identified;

[0045] The target radial basis function node determination module is used to determine the target radial basis function nodes based on the similarity between the measured strain change and the reference strain change.

[0046] The damage localization module is used to determine the damage location of the structure to be identified based on the position corresponding to the target radial basis function node.

[0047] The damage quantification module is used to determine the degree of damage to the structure to be identified based on the damage location.

[0048] An electronic device, comprising:

[0049] Memory, used to store computer programs;

[0050] A processor is used to implement the steps of any of the above-described aircraft structural damage identification methods when executing the computer program.

[0051] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of any of the above-described aircraft structural damage identification methods.

[0052] This application provides a method for identifying structural damage in an aircraft. The method involves: acquiring a target model of the structure to be identified within the aircraft; generating a target stiffness distribution information field based on radial basis function interpolation; modifying the coefficients of the radial basis function nodes in the target stiffness distribution information field to simulate damage, and generating strain changes before and after the modification as reference strain changes; acquiring the measured strain changes of the structure to be identified; determining the target radial basis function nodes based on the similarity between the measured strain changes and the reference strain changes; determining the damage location of the structure to be identified based on the corresponding positions of the target radial basis function nodes; and determining the degree of damage to the structure based on the damage location. After obtaining the target model of the structure to be identified in the aircraft, this application generates the target stiffness distribution information field of the target model based on radial basis function interpolation. This simplifies the damage characterization method through radial basis function interpolation, compresses the dimensionality of the inverse problem output, effectively addresses the sensor quantity requirements of structural health monitoring, reduces hardware demands, and better meets engineering needs. Furthermore, damage can be simulated simply by changing the coefficients of the radial basis function nodes, and reference strain changes can be generated to characterize the correlation between changes in the radial basis function node coefficients and damage. Therefore, after obtaining the measured strain changes of the structure to be identified, the target radial basis function nodes corresponding to the actual damage can be determined based on the similarity between the two values. Ultimately, the damage location and extent of the damage in the structure to be identified are determined. This achieves damage identification using strain changes, avoids the limitations of guided waves, improves the accuracy of damage identification, and the strain values ​​can be detected by strain gauges, making it low-cost and easy to promote. The aircraft structural damage identification system, electronic equipment, and computer-readable storage medium provided in this application also solve the corresponding technical problems. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0054] Figure 1 A flowchart illustrating a method for identifying structural damage in an aircraft, as provided in this application embodiment;

[0055] Figure 2 This is a schematic diagram illustrating the generation of the reference strain change.

[0056] Figure 3 A flowchart for damage identification using radial basis functions;

[0057] Figure 4 This is a schematic diagram showing the location of the strain gauges on the wing.

[0058] Figure 5 This is a schematic diagram of the finite element model of the wing;

[0059] Figure 6 A schematic diagram of the radial basis function node matrix arranged within a region enclosed by 16 strain monofilaments;

[0060] Figure 7 A schematic diagram for calculating the cosine similarity value between the measured strain change and the reference strain change of each model in the model library;

[0061] Figure 8 This is a schematic diagram showing the location of the wing damage.

[0062] Figure 9 This diagram illustrates the process of calculating radial basis function coefficients using the pattern search method.

[0063] Figure 10 This is a schematic diagram of the actual damaged unit of the wing;

[0064] Figure 11 A schematic diagram of the structure of an aircraft structural damage identification system provided in this application embodiment;

[0065] Figure 12 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application;

[0066] Figure 13 This is another structural schematic diagram of an electronic device provided in an embodiment of this application. Detailed Implementation

[0067] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0068] The structural strength of an aircraft is a factor affecting flight safety and flight quality. Currently, the demands for lightweight structural design, the promotion of new materials and structures, mechatronics design, and the diversification of mission types and service scenarios will inevitably place higher requirements on the design level of structural safety.

[0069] Online structural damage identification utilizes sensor networks and signal processing methods for real-time assessment of structural conditions, ensuring the safety of aircraft structures. For example, it can assess the location of structural damage based on changes in modal information (such as mode shapes and frequencies) after damage, and then use model correction methods to calculate the extent of damage. Alternatively, it can obtain the location of damage within the structure by processing ultrasonic guided wave signals, and then identify the extent of structural damage based on strain or modal information using model correction methods. Or, it can establish a database of typical structural damage modes and use data-driven methods such as neural networks to identify damage information through modal information or fiber optic grating information.

[0070] However, the mesh size of finite element models in actual engineering is quite large, and the amount of input sensor information is often very limited. Directly optimizing the damage reduction coefficient of all elements using the model correction method will lead to non-uniqueness of the solution to the inverse problem and ill-conditioned nature of the problem itself. The information used for damage identification includes modal information, guided waves, or fiber optic gratings, which generally have high hardware requirements, thus making them difficult to promote in engineering. Guided waves are ultrasonic signals transmitted inside the structure, which are sensitive to external forces and thermal loads and are easily interfered with by external forces and thermal loads, resulting in inaccurate damage identification results based on guided waves. Modal information often depends on all measurement points in the entire field, and it is difficult to reconstruct the entire field mode by relying solely on local measurement points. The aircraft structure damage identification method provided in this application can accurately identify aircraft structure damage while reducing hardware requirements.

[0071] Please see Figure 1 , Figure 1 A flowchart illustrating a method for identifying structural damage to an aircraft, as provided in this application embodiment.

[0072] This application provides a method for identifying structural damage to an aircraft, which may include the following steps:

[0073] Step S101: Obtain the target model of the structure to be identified in the aircraft.

[0074] In practical applications, a target model of the structure to be identified in the aircraft can be obtained first. The target model can be a finite element model, etc. The finite element model refers to the transformation of a continuous physical system into a mathematical calculation model through discretization methods.

[0075] It should be noted that the aircraft can be a drone, an airplane, etc., and the structure to be identified can be flexibly determined according to the application scenario, such as the left wing, the right wing, the tail, etc.

[0076] Step S102: Generate the target stiffness distribution information field of the target model based on radial basis function interpolation.

[0077] In practical applications, considering that radial basis function interpolation is a data interpolation method with the characteristics of simple calculation, flexible node configuration, and strong global approximation capability, and damage identification requires screening damage locations, if radial basis function interpolation is performed on the location nodes in the structure to be identified, the location nodes can be flexibly screened. Therefore, radial basis function interpolation can be applied to damage identification, that is, the target stiffness distribution information field of the target model can be generated based on radial basis function interpolation, so that the target stiffness distribution information field can be used for subsequent damage identification.

[0078] In an exemplary embodiment, during the process of generating the target stiffness distribution information field of the target model based on radial basis function interpolation, stiffness reduction information can be generated based on radial basis function interpolation; an initial stiffness distribution information field can be generated based on the stiffness reduction information; and the initial stiffness distribution information field can be mapped to the target model using the Gaussian integral method to generate the target stiffness distribution information field of the target model.

[0079] For ease of understanding, let's assume that isotropic damage can be defined as:

[0080] ;

[0081] in, Indicates the area of ​​the defect. For apparent area, This is the material degradation factor; therefore, according to the description of damage mechanics, for isotropic damage, the reduction factor can be used to define the decrease in the load-bearing capacity within the element caused by the damage, defined as:

[0082] ;

[0083] in, Represents the material degradation factor caused by damage, when A value of 0 indicates that the unit is complete. A value of 1 indicates that the unit is completely destroyed; Indicates the elastic capacity of the material; This represents the stiffness reduction factor;

[0084] Assuming that the stiffness reduction of surrounding elements caused by isotropic damage is expressed using compactly supported Gaussian radial basis functions, the stiffness reduction information is represented as follows: hour, , hour, ;

[0085] in, For shape parameters, The distance from the origin. , Coordinates representing the location, To support the radius;

[0086] Based on the stiffness reduction information, an initial stiffness distribution information field is generated, which is also the damage characterization method based on radial basis functions. By determining the coefficients of each node in the radial basis function field, the stiffness distribution of the entire field is determined. The initial stiffness distribution information field is then expressed as:

[0087] ;

[0088] in, , Let represent the radial basis functions, where i and j represent position numbers. The node numbers of the radial basis functions are the same as their position numbers. This represents the coefficient corresponding to the radial basis function node at position j. The representative position is The values ​​of the radial basis function field at time t, and the initial stiffness distribution information field can be simplified as: ;

[0089] The stiffness obtained using radial basis functions is continuous and needs to be mapped onto the finite element model to correct the element stiffness. This can be achieved by using the Gaussian integral method to map the initial stiffness distribution information field onto the target model, generating the target stiffness distribution information field. The expression for the target stiffness distribution information field is:

[0090] ;

[0091] Where Y represents the functional expression of the stiffness field.

[0092] Step S103: Change the coefficients of the radial basis function nodes in the target stiffness distribution information field to simulate damage, and generate the strain change before and after changing the radial basis function nodes as the reference strain change.

[0093] In practical applications, since each radial basis function node in the target stiffness distribution information field represents a location, changing the coefficient value of this radial basis function node allows for the simulation of damage at that location. This reveals the strain change after damage occurs at that location. In other words, the coefficients of the radial basis function nodes in the target stiffness distribution information field can be modified to simulate damage, generating strain changes before and after the modification as reference strain changes. Thus, the reference strain change corresponding to each radial basis function node represents the damage information at that node's location. Furthermore, based on the modified radial basis function nodes and their corresponding reference strain changes, a damage-strain model library based on radial basis functions can be established for the structure to be identified. This allows for flexible and convenient management and application of the radial basis function nodes and their corresponding reference strain changes.

[0094] In specific application scenarios, when modifying the coefficients of the radial basis function nodes in the target stiffness distribution information and generating the strain changes before and after the modification as reference strain changes, the coefficients of each radial basis function node in the target stiffness distribution information can be changed sequentially. Parametric simulation is then used to generate simulated strain changes before and after the modification of the radial basis function nodes. These simulated strain changes are then used as reference strain changes for the corresponding radial basis function nodes. For ease of understanding, assume the number of radial basis function field nodes is n, where n is selected based on the analysis accuracy. Damage occurs at each node; that is, modifying the coefficient of this radial basis function node to 1, while the coefficients of other nodes remain 0. , ,like Figure 2 As shown, the static response of the damaged structure at the strain measurement point is calculated through parametric simulation, that is, the strain signal vector before and after damage is obtained. The difference between the strain signal vectors before and after damage is used as the reference strain change, resulting in n patterns, thus establishing a damage-strain pattern library. The strain change SS is represented as... , This represents the strain signal vector after damage. This represents the strain signal vector before damage.

[0095] Step S104: Obtain the measured strain change of the structure to be identified.

[0096] In practical applications, if the structure to be identified is damaged, the stress of the structure will change before and after the damage. Therefore, the measured strain change of the structure to be identified can be obtained, and the damage can be identified by using the measured strain change.

[0097] Step S105: Determine the target radial basis function node based on the similarity between the measured strain change and the reference strain change. In practical applications, the more similar the measured strain change and the reference strain change of the structure to be identified, the more consistent the radial basis function node corresponding to the measured strain change will be with the radial basis function node corresponding to the reference strain change. Therefore, the target radial basis function node can be determined based on the similarity between the measured strain change and the reference strain change. That is, the radial basis function node corresponding to the reference strain change that is most similar to the measured strain change is determined as the target radial basis function node. This target radial basis function node is also the corresponding node in the structure to be identified where actual damage has occurred.

[0098] In an exemplary embodiment, during the process of determining the target radial basis function node based on the similarity between the measured strain change and the reference strain change, a cosine similarity value between the measured strain change and each reference strain change can be generated; the reference strain change corresponding to the maximum cosine similarity value can be used as a candidate strain change; and the radial basis function node corresponding to the candidate strain change can be used as the target radial basis function node.

[0099] In specific application scenarios, during the generation of cosine similarity values ​​between the measured strain change and each reference strain change, the measured strain change can be normalized to obtain a first normalized value; the reference strain changes can be normalized to obtain a second normalized value. During the normalization process, the strain response before damage can be used, for example, the normalization formula is: i=1,……,n Let represent the normalized value of the i-th radial basis function node. This represents the stress response value corresponding to damage at the i-th radial basis function node. This represents the stress response value before damage; it generates cosine similarity values ​​between the first normalized value and each of the second normalized values. The formula for generating the cosine similarity value can then be:

[0100] ;

[0101] Represents the cosine similarity value. This represents the first normalized value. This represents the second normalized value; This represents the dot product of vectors.

[0102] Step S106: Determine the damage location of the structure to be identified based on the location of the target radial basis function node.

[0103] Step S107: Determine the degree of damage to the structure to be identified based on the location of the damage.

[0104] In practical applications, since each radial basis function node corresponds to a position in the structure to be identified, after determining the target radial basis function node, the damage location of the structure to be identified can be determined based on the position corresponding to the target radial basis function node. For example, the position corresponding to the target radial basis function node can be determined as the damage location of the structure to be identified, or the position corresponding to the target radial basis function node and the position within a set length of the edge can be determined as the damage location of the structure to be identified. Then, based on the damage location, the degree of damage to the structure to be identified can be determined.

[0105] In practical applications, after determining the damage location, it is necessary to construct an objective function for the damage variable. The true damage state is obtained by minimizing the objective function through a modified finite element model. In this process, considering that existing methods directly correct the stiffness of the suspected element, there is ill-posedness in the solution of the inverse problem. To avoid this situation, this application proposes a damage degree quantification method based on radial basis function interpolation. This simplifies the variable of this inverse problem to a single variable: the radial basis node coefficient of the damage location. That is, in the process of determining the damage degree of the structure to be identified based on the damage location, the reduction of stiffness after damage can be determined by modifying the node coefficient of the radial basis node at the damage location, thereby achieving damage degree quantification.

[0106] In specific applications, the damage quantification process can be optimized by making the strain change at the damage location as close as possible to the measured value. In other words, the strain value after changing the radial basis function nodes can be used as a reference strain value. ; Obtain the measured strain values ​​of the structure to be identified Based on the reference strain value and the measured strain value, a damage quantification model is generated at the damage location. For example, the quantification model is used to find the condition that satisfies the reference strain value and the measured strain value. of , m represents the number of damaged elements; the stiffness reduction factor at the damage location is generated based on radial basis function interpolation. , , Here, m represents the number of damaged elements. Based on the stiffness reduction factor, the damage degree quantification model is processed, i.e., solved, to generate the radial basis function nodal coefficients at the damage location. Based on these radial basis function nodal coefficients, the damage degree at the damage location is determined. For example, the radial basis function field corresponding to the actual damage degree is determined based on the radial basis function nodal coefficients. This radial basis function field is then mapped onto the damaged elements to determine the damage degree. The entire process can be described as follows: Figure 3 As shown.

[0107] In an exemplary embodiment, during the process of processing the damage quantification model to generate the radial basis function nodal coefficients at the damage location, a pattern search method can be used to process the damage quantification model and generate the radial basis function nodal coefficients at the damage location. This allows for the rapid generation of radial basis function nodal coefficients using the pattern search method.

[0108] This application provides a method for identifying structural damage in an aircraft. The method involves: acquiring a target model of the structure to be identified within the aircraft; generating a target stiffness distribution information field based on radial basis function interpolation; modifying the coefficients of the radial basis function nodes in the target stiffness distribution information field to simulate damage, and generating strain changes before and after the modification as reference strain changes; acquiring the measured strain changes of the structure to be identified; determining the target radial basis function nodes based on the similarity between the measured strain changes and the reference strain changes; determining the damage location of the structure to be identified based on the corresponding positions of the target radial basis function nodes; and determining the degree of damage to the structure based on the damage location. After obtaining the target model of the structure to be identified in the aircraft, this application generates the target stiffness distribution information of the target model based on radial basis function interpolation. This simplifies the damage characterization method by using radial basis function interpolation, compresses the dimension of the inverse problem output, effectively solves the requirement for the number of sensors in structural health monitoring, reduces hardware requirements, and better meets engineering needs. Moreover, damage can be simulated by simply changing the coefficients of the radial basis function nodes, and reference strain changes can be generated to characterize the correlation between the changes in the radial basis function node coefficients and the damage. Thus, after obtaining the measured strain changes of the structure to be identified, the target radial basis function nodes corresponding to the actual damage can be determined based on the similarity between the two, and finally the damage location and damage degree of the structure to be identified can be determined. This achieves damage identification by using strain changes, avoids the limitations of guided waves, improves damage identification efficiency, and the strain value can be detected by strain gauges, making it low-cost and easy to promote.

[0109] To verify the accuracy and effectiveness of the aircraft structural damage identification scheme provided in this application, an experimental verification was conducted on a perforation damage in the upper panel of the left wing of an aircraft. It was assumed that a circular perforation damage with a diameter of approximately 20 mm was pre-placed in the middle of the upper panel at a certain location on the wing, and 4×4 x-axis strain gauges, numbered JZ17-JZ32, were arranged around it. The structural health monitoring area enclosed by the strain gauges was as follows: Figure 4 As shown.

[0110] A finite element model for detailed analysis of the upper wing panel was created using ANSYS APDL. ANSYS APDL allows for rapid modeling and modification of element properties via command flow, followed by static analysis using batch files. The finite element model is shown below. Figure 5 As shown in the figure, different element depths represent different composite material section properties. Displacement boundaries in the x, y, and z directions are extracted from the overall static strength analysis model of the aircraft and interpolated into the panel detail analysis model in ANSYS. The static response before structural damage is then calculated.

[0111] like Figure 6As shown, within a region enclosed by 16 strain monolayers, a 45x50 radial basis function node matrix is ​​uniformly arranged. Following the scheme of this application, the radial basis function node coefficients are modified, and the damage characterized by the radial basis function field is mapped onto the damage element. The reference strain change corresponding to damage at each radial basis node is calculated. A 45x50 damage mode library is generated based on these radial basis nodes.

[0112] Calculate the cosine similarity value between the measured strain change and the reference strain change of each model in the model library, such as... Figure 7 As shown, the damage mode that most closely matches the measured signal is determined based on the degree of proximity, such as... Figure 8 As shown, the calculated highest proximity is 0.9608, corresponding to damage locations of [4297mm, 4926mm]. The actual damage locations are [4300mm, 4924mm]. The location identification error is 3.6mm. Considering strain gauge placement errors and experimental loading fluctuations, this identification accuracy is considered satisfactory.

[0113] After determining the mode corresponding to the damage location, the radial basis function coefficients are inverted using the mode search method. The calculation process is as follows: Figure 9 As shown; the actual damaged unit is as follows Figure 10 As shown in Table 1, the degree of damage to the unit is as follows.

[0114] Table 1 Unit Damage Level Table

[0115]

[0116] The calculated damage area is 292 mm². 2 The actual damaged area is mm 2 With a relative error of 7%, the damage location and extent identified by the proposed solution meet the requirements of accuracy and effectiveness.

[0117] Please see Figure 11 , Figure 11 This is a schematic diagram of the structure of an aircraft structural damage identification system provided in an embodiment of this application.

[0118] This application provides an embodiment of an aircraft structural damage identification system, which may include:

[0119] Model acquisition module 101 is used to acquire the target model of the structure to be identified in the aircraft.

[0120] The stiffness distribution generation module 102 is used to generate the target stiffness distribution information field of the target model based on radial basis function interpolation.

[0121] Damage simulation module 103 is used to change the coefficients of the radial basis function nodes in the target stiffness distribution information field to simulate damage, and to generate the strain change before and after changing the radial basis function nodes as a reference strain change.

[0122] The measured strain change acquisition module 104 is used to acquire the measured strain change of the structure to be identified.

[0123] The target radial basis function node determination module 105 is used to determine the target radial basis function nodes based on the similarity between the measured strain change and the reference strain change.

[0124] The damage localization module 106 is used to determine the damage location of the structure to be identified based on the position of the target radial basis function node.

[0125] The damage quantification module 107 is used to determine the degree of damage to the structure to be identified based on the location of the damage.

[0126] This application provides an embodiment of an aircraft structural damage identification system, wherein the stiffness distribution generation module may include:

[0127] The stiffness reduction information generation unit is used to generate stiffness reduction information based on radial basis function interpolation.

[0128] The initial stiffness distribution generation unit is used to generate an initial stiffness distribution information field based on stiffness reduction information.

[0129] The target stiffness distribution generation unit is used to map the initial stiffness distribution information field to the target model using the Gaussian integral method, thereby generating the target stiffness distribution information field of the target model.

[0130] This application provides an embodiment of an aircraft structural damage identification system, wherein the damage simulation module may include:

[0131] The damage simulation unit is used to sequentially change the coefficients of each radial basis function node in the target stiffness distribution information to simulate damage, and generates the simulated strain changes before and after changing the radial basis function nodes through parametric simulation.

[0132] The reference strain change determination element is used to take the simulated strain change as the reference strain change corresponding to the radial basis function node.

[0133] This application provides an embodiment of an aircraft structural damage identification system, wherein the target radial basis function node determination module may include:

[0134] The similarity generation unit is used to generate cosine similarity values ​​between the measured strain change and each reference strain change.

[0135] The filtering unit is used to select the reference strain change corresponding to the maximum cosine similarity value as the candidate strain change.

[0136] The target radial basis function node determination element is used to determine the radial basis function nodes corresponding to the candidate strain changes as the target radial basis function nodes.

[0137] This application provides an aircraft structural damage identification system, in which a similarity generation unit is used to: normalize the measured strain change to obtain a first normalized value; normalize the reference strain change to obtain a second normalized value; and generate cosine similarity values ​​between the first normalized value and each of the second normalized values.

[0138] This application provides an embodiment of an aircraft structural damage identification system, wherein the damage quantification module may include:

[0139] The reference strain value acquisition unit is used by the damage location module to obtain the strain value after changing the radial basis function node as the reference strain value after determining the damage location of the structure to be identified based on the location corresponding to the target radial basis function node.

[0140] The measured strain value acquisition unit is used to acquire the measured strain value of the structure to be identified;

[0141] The quantification model generation unit is used to generate a quantification model of the damage degree at the damage location based on the reference strain value and the measured strain value.

[0142] The stiffness reduction factor generation unit is used to generate the stiffness reduction factor at the damage location based on radial basis function interpolation.

[0143] The coefficient generation unit is used to process the damage degree quantification model based on the stiffness reduction factor and generate the radial basis function nodal coefficients at the damage location.

[0144] The damage degree determination unit is used to determine the damage degree at the damage location based on the radial basis function node coefficients at the damage location.

[0145] This application provides an aircraft structural damage identification system. The coefficient generation unit can be used to: process the damage degree quantification model through a pattern search method to generate radial basis function node coefficients at the damage location.

[0146] This application also provides an electronic device and a computer-readable storage medium, both of which have the corresponding effects of the aircraft structural damage identification method provided in the embodiments of this application. Please refer to... Figure 12 , Figure 12 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0147] An electronic device provided in this application includes a memory 201 and a processor 202. The memory 201 stores a computer program, and when the processor 202 executes the computer program, it implements the steps of the aircraft structural damage identification method described in any of the above embodiments.

[0148] Please see Figure 13 Another electronic device provided in this application embodiment may further include: an input port 203 connected to the processor 202 for transmitting commands input from the outside to the processor 202; a display unit 204 connected to the processor 202 for displaying the processing results of the processor 202 to the outside; and a communication module 205 connected to the processor 202 for enabling communication between the electronic device and the outside. The display unit 204 may be a display panel, a laser scanner, or the like; the communication method used by the communication module 205 includes, but is not limited to, Mobile High-Definition Link (MHL), Universal Serial Bus (USB), High-Definition Multimedia Interface (HDMI), wireless connectivity: Wireless Fidelity (WiFi), Bluetooth communication technology, Bluetooth Low Energy communication technology, and communication technology based on IEEE 802.11s.

[0149] This application provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the steps of the aircraft structural damage identification method described in any of the above embodiments.

[0150] The computer-readable storage media involved in this application include random access memory (RAM), memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disks, removable disks, CD-ROMs (compact disc read-only memory), or any other form of storage media known in the art.

[0151] This application provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the steps of the aircraft structural damage identification method described in any of the above embodiments.

[0152] For descriptions of relevant parts of the aircraft structural damage identification system, electronic device, and computer-readable storage medium provided in this application's embodiments, please refer to the detailed description of the corresponding parts in the aircraft structural damage identification method provided in this application's embodiments; they will not be repeated here. Furthermore, parts of the technical solutions provided in this application that are consistent with the implementation principles of corresponding technical solutions in the prior art have not been described in detail to avoid excessive elaboration.

[0153] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0154] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for identifying structural damage in aircraft, characterized in that, include: Obtain the target model of the structure to be identified in the aircraft; Based on radial basis function interpolation, the target stiffness distribution information field of the target model is generated; The coefficients of the radial basis function nodes in the target stiffness distribution information field are changed to simulate damage, and the strain change before and after changing the radial basis function nodes is generated as a reference strain change. Obtain the measured strain change of the structure to be identified; The target radial basis function nodes are determined based on the similarity between the measured strain change and the reference strain change. The damage location of the structure to be identified is determined based on the position corresponding to the target radial basis function node; Based on the location of the damage, the degree of damage to the structure to be identified is determined; The step of generating the target stiffness distribution information field of the target model based on radial basis function interpolation includes: Stiffness reduction information is generated based on radial basis function interpolation; Based on the stiffness reduction information, an initial stiffness distribution information field is generated; The initial stiffness distribution information field is mapped to the target model using the Gaussian integral method to generate the target stiffness distribution information field of the target model. The step of determining the target radial basis function node based on the similarity between the measured strain change and the reference strain change includes: Generate the cosine similarity value between the measured strain change and each of the reference strain changes; The reference strain change corresponding to the highest cosine similarity value is used as the candidate strain change. The radial basis function nodes corresponding to the candidate strain changes are used as the target radial basis function nodes.

2. The method according to claim 1, characterized in that, The step of modifying the coefficients of the radial basis function nodes in the target stiffness distribution information field and generating the strain change before and after modifying the radial basis function nodes as a reference strain change includes: The coefficients of each radial basis function node in the target stiffness distribution information field are changed sequentially, and the simulated strain change before and after changing the radial basis function nodes is generated through parametric simulation. The simulated strain change is used as the reference strain change for the radial basis function node.

3. The method according to claim 1, characterized in that, The generation of cosine similarity values ​​between the measured strain change and each of the reference strain changes includes: The measured strain change is normalized to obtain the first normalized value; The reference strain change is normalized to obtain a second normalized value; Generate cosine similarity values ​​between the first normalized value and each of the second normalized values.

4. The method according to any one of claims 1 to 3, characterized in that, Determining the degree of damage to the structure to be identified based on the damage location includes: Obtain the strain value after changing the radial basis function nodes as the reference strain value; Obtain the measured strain value of the structure to be identified; Based on the reference strain value and the measured strain value, a damage degree quantification model is generated at the damage location; Based on radial basis function interpolation, the stiffness reduction factor at the damage location is generated; Based on the stiffness reduction factor, the damage degree quantification model is processed to generate the radial basis function nodal coefficients at the damage location; The degree of damage at the damage location is determined based on the radial basis function node coefficients at the damage location.

5. The method according to claim 4, characterized in that, The process of processing the damage quantification model to generate the radial basis function nodal coefficients at the damage location includes: The damage quantification model is processed by a pattern search method to generate the radial basis function node coefficients at the damage location.

6. A damage identification system for aircraft structures, characterized in that, include: The model acquisition module is used to acquire the target model of the structure to be identified in the aircraft; The stiffness distribution generation module is used to generate the target stiffness distribution information field of the target model based on radial basis function interpolation. The damage simulation module is used to change the coefficients of the radial basis function nodes in the target stiffness distribution information field to simulate damage, and to generate the strain change before and after changing the radial basis function nodes as a reference strain change. The measured strain change acquisition module is used to acquire the measured strain change of the structure to be identified; The target radial basis function node determination module is used to determine the target radial basis function nodes based on the similarity between the measured strain change and the reference strain change. The damage localization module is used to determine the damage location of the structure to be identified based on the position corresponding to the target radial basis function node. The damage quantification module is used to determine the degree of damage to the structure to be identified based on the damage location. The stiffness distribution generation module includes: The stiffness reduction information generation unit is used to generate stiffness reduction information based on radial basis function interpolation. An initial stiffness distribution generation unit is used to generate an initial stiffness distribution information field based on the stiffness reduction information. The target stiffness distribution generation unit is used to map the initial stiffness distribution information field to the target model using the Gaussian integral method, thereby generating the target stiffness distribution information field of the target model. The target radial basis function node determination module includes: A similarity generation unit is used to generate cosine similarity values ​​between the measured strain change and each of the reference strain changes; The filtering unit is used to select the reference strain change corresponding to the highest cosine similarity value as the candidate strain change. The target radial basis function node determination unit is used to determine the radial basis function nodes corresponding to the candidate strain changes as the target radial basis function nodes.

7. An electronic device, characterized in that, include: Memory, used to store computer programs; A processor, configured to implement the steps of the aircraft structural damage identification method as described in any one of claims 1 to 5 when executing the computer program.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the aircraft structural damage identification method as described in any one of claims 1 to 5.

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