Aircraft structure MSG-3 analysis accidental damage assessment method

Abstract

The invention belongs to the technical field of maintenance engineering, and relates to an aircraft structure MSG-3 analysis accidental damage assessment method. The method comprises the following steps: identifying accidental damage influence factors of an aircraft structure according to aircraft operation characteristics, and establishing an accidental damage factor list according to the determined accidental damage influence factors of the aircraft structure; and establishing an evaluation rule of each accidental damage influence factor according to damage forms and occurrence characteristics of different accidental damage factors. Establishing a two-tuple according to aircraft configuration parameter indexes; and establishing an accidental damage factor incidence matrix for evaluating the total accidental damage score of the structure. And determining a structural analysis object, and extracting key parameters according to the mathematical model of the analysis object. And establishing a feature vector of the structure analysis object. And in combination with the scoring rule of each accidental damage influence factor, discriminating and analyzing the score of each accidental damage influence factor of the structure object. And the final accidental damage influence is obtained through the incidence matrix. And the accuracy and effectiveness of analysis data as well as effectiveness and reliability of data use and transmission are ensured.

Description

Technical Field

[0001] This invention belongs to the field of operation support technology / maintenance engineering technology, and relates to a method for assessing accidental damage in aircraft structure MSG-3 analysis. Background Technology

[0002] Aircraft maintenance work can be divided into planned maintenance tasks and unplanned maintenance tasks. Planned maintenance tasks are the foundation for ensuring the inherent design level and continued airworthiness of an aircraft. Therefore, the airworthiness standards of various civil aviation authorities all include planned maintenance requirements as an important part of the continued airworthiness documentation, and it is also the responsibility of the aircraft manufacturer or type certificate holder to prepare the planned maintenance requirements document.

[0003] Currently, when conducting SSI (Safety Indicator) planned maintenance analysis for newly developed aircraft in China, due to a lack of extensive analytical experience and maintenance-related data, domestic analysts primarily refer to the SSI planned maintenance analysis methods of similar aircraft models from Boeing and Airbus. However, in the specific implementation of planned maintenance analysis, different users use different aircraft models and employ varying analytical methods. Regarding the assessment of incidental damage in structural planned maintenance analysis, due to differing subjective perceptions, different individuals may reach different conclusions for the same structural component. This method proposes an automated scoring approach that can automatically assess incidental damage to structural components using a computer. Summary of the Invention

[0004] Purpose of the invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a comprehensive and standardized planned maintenance analysis method and system for aircraft structural planned maintenance tasks, achieving comprehensive analysis of structural planned maintenance methods through a step-by-step analysis process.

[0006] Technical solution

[0007] This invention provides a method for assessing accidental damage in aircraft structures using MSG-3 analysis. MSG-3 is an aviation maintenance standard developed by the Air Transport Association (ATA) and is primarily used to develop initial maintenance programs for aircraft and engines. This method only requires judgment based on established MSG-3 analysis rules to determine the accidental damage level of the analyzed structural component, thereby reducing subjective errors, increasing the efficiency of MSG-3 analysis, and saving labor and time costs.

[0008] The MSG-3 analysis method for assessing accidental damage to aircraft structures includes:

[0009] S1: Based on the characteristics of aircraft operation, identify the factors that cause accidental damage to the aircraft structure, and establish a list of accidental damage factors based on the identified factors.

[0010] S2: Based on the list of accidental damage influencing factors obtained in S1, establish evaluation rules for each accidental damage influencing factor according to the damage form and occurrence characteristics of different accidental damage factors.

[0011] S3: Based on the evaluation rules established in S2, scored binary groups are established according to indicators such as aircraft configuration, region, maintenance cover and design parameters, which can be used for classifier.

[0012] S4: Based on the characteristics of the factors influencing accidental damage to the aircraft structure, establish a correlation matrix of accidental damage factors to evaluate the total accidental damage score of the structure.

[0013] S5: Determine the structural analysis object and extract key parameters based on the mathematical model of the analysis object, such as shape, assembly relationship, material, and protective measures.

[0014] S6: Establish the feature vector of the structural analysis object based on the key parameters extracted in S5.

[0015] S7: Based on the feature vector extracted in S6 and the scoring rules of each accidental damage influencing factor, the scores of each accidental damage influencing factor of the structural object are determined and analyzed.

[0016] S8: Based on the scores of each accidental damage influencing factor calculated in S7, the final accidental damage impact is obtained through the correlation matrix.

[0017] Furthermore, according to S1, the factors influencing accidental damage are divided into four parts: accidental damage source, residual strength, visibility, and damage propagation sensitivity. The evaluation of the accidental damage source describes the likelihood of the accidental damage factor occurring in the aircraft structure, and is divided into four levels: high, medium, low, and impossible. Residual strength characterizes the maximum load-bearing capacity of the cracked structure, and is divided into three levels: high, medium, and low. Visibility is used to describe and analyze the maintainability of structural components, and is divided into three levels: good, medium, and bad. Damage propagation sensitivity should be assessed based on stress level and material properties, reflecting the structural performance when damage and stress are combined, and is divided into three levels: insensitive, moderately sensitive, and sensitive.

[0018] Furthermore, in S2, based on the aircraft's operational characteristics, structural features, and the damage modes of accidental damage influencing factors, a list of influencing factors is compiled. The list includes all factors that may affect the assessment of accidental damage, and specific evaluation rules are given for the influencing factors in the list.

[0019] Furthermore, in S3, based on the evaluation rules for factors influencing accidental damage, and combined with indicators such as aircraft configuration, area, maintenance access panels, and design parameters, the evaluation rules are digitized to form a discriminant vector. The discriminant vector is constructed as follows:

[0020] in: , , The SSI number indicates the subsystem or sub-subsystem to which the SSI belongs, as well as the sequential number of the structural item. , , , These are the location parameters of the structure being analyzed, used to describe the position of the structural component within the frame, stringer, or rib of the aircraft. For example, when the structural component being analyzed is located in the fuselage... , , , This indicates the frame and stringer where the structural components are located; This indicates the internal and external parameters of the structural component. The parameters are set according to whether the structural component is external. For example, the parameter of the outer surface of the skin is 1, the parameter of the inner surface of the skin and the stringer is 2, and so on. These are shape parameters, arranged according to the size of the structural components; , , These are the visibility parameters, strength parameters, crack propagation parameters, and corrosion protection parameters for the structural components, provided in the aircraft design documents. If any parameter is uncertain, it is set to 0.

[0021] Based on the scoring rules, a binary tuple is formed by assigning a score to the discriminant vector. . This indicates the score under the corresponding scoring rules.

[0022] Furthermore, considering the characteristics of the factors influencing accidental damage, a correlation matrix of accidental damage factors is established by integrating various factors influencing accidental damage. This matrix is ​​used to calculate the final total level of accidental structural damage.

[0023] Furthermore, the analysis object is determined, which includes both metallic and non-metallic structures. Key parameters are extracted from the mathematical model of the analysis object, including one or more of the following: shape, assembly relationship, material, and protective measures.

[0024] Furthermore, the key parameters of the analysis object are digitized, transforming text parameters into numerical parameters and forming a feature vector with the same dimension as the discriminant vector formed by the scoring rules.

[0025] Furthermore, for all accidental damage factors, an automatic scoring system is used. The nearest neighbor classifier determines the damage by calculating the weighted distance between the feature vector and the discriminant vector, classifying the input feature vector based on the principle of minimizing the distance, and providing scores for each accidental damage factor affecting the analyzed structure. The discrimination criteria are as follows: , ,

[0026] in, For belonging to the feature vector All discriminant vector samples within the nearest neighbor region, For sample weights, For feature vectors and belonging to The The distance between each feature vector. The weight matrix is ​​a diagonal matrix, representing... The weight of each component in the vector.

[0027] Furthermore, for different accidental damage factors, different weight matrices are set according to the description in their scoring rules and the meaning represented by the components in the feature vector.

[0028] Furthermore, observe the vectors Each vector in the vector has a different meaning. Furthermore, based on the characteristics of the structural components and the corresponding data, the eigenvectors... The components may contain unknowns, so relevant rules need to be established when calculating distances. For example, location parameters... , This refers to the frame in which the structure is located, which can form a range. shape parameters This represents a point. The distance calculation rules are as follows:

[0029] Rule 1: If or ,make or

[0030] Rule 2: If ,make .

[0031] Furthermore, by comprehensively analyzing the scores of all accidental damage factors assessed by the structural analysis object, the final impact of accidental structural damage is evaluated through correlation matrix calculation.

[0032] Technical effect

[0033] This method meets the requirements of MSG-3 structural analysis for accidental damage analysis and assessment, and realizes the automation, informatization, process monitoring, and integration of configuration and data management of analysis and assessment, ensuring the accuracy and validity of analysis data, as well as the effectiveness and reliability of data use and transmission.

[0034] The method provides structural management functions, enabling the storage and management of information on analyzed structural components, and supporting the addition, deletion, and editing of information. It also provides a list management function for accidental damage influencing factors, supporting the addition, deletion, and editing of accidental damage factors and their scoring rules. Furthermore, it offers a correlation matrix unit for accidental damage influencing factors, which, based on a defined correlation matrix, integrates the scores of all factors in the accidental damage influencing factor list to derive a total impact score. Finally, it provides an accidental damage analysis unit, which automatically assesses accidental damage to the structure based on the input parameters of the analyzed structure. This method effectively avoids assessment errors caused by human factors, standardizes structural MSG-3 analysis scoring, increases the efficiency of structural MSG-3 analysis, and reduces R&D costs during aircraft development and maintenance and operation costs after aircraft enter service. This method can be used for environmental impact analysis of structural MSG-3, regional MSG-3 analysis, and other analysis processes with given evaluation rules. In addition, the assessment of accidental damage in structural MSG-3 can provide analytical basis for optimizing planned maintenance requirements and iterative aircraft optimization, meeting the development requirements of digitalization and informatization in aircraft maintenance management and providing technical support. Attached Figure Description

[0035] Figure 1 This is a flowchart of the MSG-3 analysis and accidental damage assessment method for aircraft structures according to the present invention.

[0036] Figure 2 This is a classification diagram of accidental damage factors in the MSG-3 analysis and accidental damage assessment method for aircraft structures according to the present invention.

[0037] Figure 3 This is a schematic diagram of the scoring rules for the MSG-3 analysis and accidental damage assessment method for aircraft structures according to the present invention.

[0038] Figure 4 This invention relates to the accidental damage correlation matrix of the MSG-3 analysis method for assessing accidental damage in aircraft structures.

[0039] Figure 5 This is a schematic diagram of the feature vectors of the MSG-3 analysis method for assessing accidental damage to aircraft structures according to the present invention.

[0040] Figure 6 This is a schematic diagram of the nearest neighbor classifier in the MSG-3 analysis and accidental damage assessment method for aircraft structures of the present invention. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setup and method set forth below, but covers any improvements, substitutions, and modifications to the structures, methods, and devices without departing from the spirit of the invention. In the following description, well-known structures and techniques are not shown to avoid unnecessarily obscuring the invention.

[0043] In the description of this invention, it should be noted that the directions or positional relationships indicated by terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" are based on the stated directions or positional relationships and are only for the convenience of describing and simplifying the invention, and should not be construed as limiting the invention. Furthermore, the use of ordinal numbers (e.g., "first and second," etc.) is for distinguishing objects and is not limited to this order, and should not be construed as indicating or implying relative importance.

[0044] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly, encompassing both direct connection and indirect connection via an intermediate medium. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0045] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited in each other. The present invention will now be described in detail with reference to and in conjunction with the embodiments.

[0046] This invention uses the civil aviation planned maintenance analysis system as a framework and focuses on the assessment of accidental damage in aircraft structure MSG-3 analysis, proposing a process and method for assessing accidental damage in aircraft structure MSG-3 analysis.

[0047] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0048] This invention relates to a method for assessing accidental damage in MSG-3 analysis of aircraft structures. It is applicable to MSG-3 accidental damage assessment methods, and automatically generates accidental damage assessments for structural components by evaluating factors influencing accidental damage. This reduces repetitive manual judgment and human error, increasing the accuracy of MSG-3 analysis. (See appendix) Figure 1 .

[0049] The method for assessing accidental damage to aircraft structures using the MSG-3 analysis method is as follows:

[0050] Step 1: Based on the aircraft's operational characteristics, identify potential accidental damage to the aircraft structure and establish a list of accidental damage factors based on the identified influencing factors. Accidental damage factors mainly consist of four parts: visibility, damage propagation, residual strength, and accidental damage source. Visibility is comprised of access panel size, inspection distance, and equipment density. Accidental damage sources include human factors, foreign objects, weather, lightning strikes, and liquid splashes, etc. (See Appendix). Figure 2 .

[0051] Step 2: Based on the definition and requirements of accidental damage, and according to the damage form and occurrence characteristics of different accidental damage factors, determine the scoring rules for all accidental damages in the accidental damage list.

[0052] Step 3: Based on the evaluation rules for accidental damage influencing factors, and considering the aircraft configuration, as well as indicators such as area, maintenance access panels, and design parameters, transform a certain evaluation rule into one or more discriminant vectors, forming binary pairs. Each discriminant vector corresponds to a score, with scores of 1, 2, and 3. (See Appendix) Figure 3 .

[0053] The discriminant vector is constructed as follows:

[0054]

[0055] in: , , The SSI number indicates the subsystem or sub-subsystem to which the SSI belongs, as well as the sequential number of the structural item. , , , For the positional parameters of the structure being analyzed, is used to describe the location of the structural component within the frame, stringer, or rib of the aircraft. For example, when the structural component being analyzed is located in the fuselage... , , , This indicates the frame and stringer where the structural components are located; This indicates the internal and external parameters of the structural component. The parameters are set according to whether the structural component is external. For example, the parameter of the outer surface of the skin is 1, the parameter of the inner surface of the skin and the stringer is 2, and so on. These are shape parameters, arranged according to the size of the structural components; , , These are the visibility parameters, strength parameters, crack propagation parameters, and corrosion protection parameters for the structural components, provided in the aircraft design documents. If any parameter is uncertain, it is set to 0.

[0056] Based on the scoring rules, a binary tuple is formed by assigning a score to the discriminant vector.

[0057] Step 4: Based on the characteristics of the factors influencing accidental damage, a correlation matrix of accidental damage factors is established by integrating all these factors. This matrix is ​​used to calculate the final overall accidental damage level of the structure. The correlation matrix consists of three matrices: the first is the visibility / damage propagation correlation matrix, which calculates a comprehensive score based on both visibility and damage propagation scores; the second is the damage probability / remaining strength correlation matrix, which calculates a comprehensive score based on both the accidental damage source and remaining strength scores; the third is the overall AD level correlation matrix, which calculates the final overall AD level based on the scores from the first and second matrices. (See Appendix) Figure 4 .

[0058] Step 5: Based on the identified metallic or non-metallic analysis object, extract one or more key parameters such as shape, assembly relationship, material, and protective measures from its digital model.

[0059] Step 6: Perform the same digitization process on the key parameters of the analyzed object as the evaluation rules, converting text parameters into numerical parameters and forming a feature vector with the same dimension as the discriminant vector formed by the scoring rules. The construction of the feature vector is consistent with that of the discriminant vector, derived from the SSI number, region, structure name, material type, coating protection, access cover, and design document information of the analyzed structure. See Appendix. Figure 5 .

[0060] Step 7: Based on the digitized feature vectors, score all accidental damage influencing factors using a nearest neighbor classifier. According to the predefined nearest neighbor classifier principle, compare the distance between the feature vector and the discriminant vector, and take the closest distance as the score for the accidental damage factor corresponding to that feature vector. (See Appendix) Figure 6 .

[0061] The nearest neighbor classifier classifies input feature vectors by calculating the weighted distance between feature vectors and discriminant vectors, using the principle of minimizing distance as the criterion. It then assigns scores to various accidental damage factors affecting the analyzed structure. Its discrimination criteria are as follows:

[0062]

[0063]

[0064]

[0065] in, For belonging to the observation vector All discriminant vector samples within the nearest neighbor region, For sample weights, For feature vectors and belonging to The The distance between training samples, The weight matrix is ​​a diagonal matrix, representing... The weight of each component in the vector.

[0066] Step 8: Based on the different accidental damage factors and their descriptions in the scoring rules, set different weight matrices according to the meanings represented by the components in the feature vector.

[0067] Step 9: Observe the vectors Each vector in the vector has a different meaning. Furthermore, based on the characteristics of the structural components and the corresponding data, the eigenvectors... The components may contain unknowns, so relevant rules need to be established when calculating distances. For example, location parameters... , This refers to the frame in which the structure is located, which can form a range. shape parameters This represents a point. The distance calculation rules are as follows:

[0068] Rule 1: If or ,make or

[0069] Rule 2: If ,make ...

[0070] Step 10: The scores of all accidental damage factors assessed by the basic comprehensive structural analysis object are calculated through the correlation matrix to evaluate the final impact of accidental structural damage.

[0071] The above detailed embodiments are a description of the present invention. It should not be considered that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, several simple deductions and substitutions can be made without departing from the concept of the present invention, and all of these should be considered to fall within the protection scope of the present invention.

Claims

1. A method for assessing accidental damage in aircraft structure MSG-3 analysis, characterized in that, Include: S1: Based on the characteristics of aircraft operation, identify the factors that cause accidental damage to the aircraft structure, and establish a list of accidental damage factors based on the identified factors. S2: Based on the list of accidental damage influencing factors obtained in S1, establish evaluation rules for each accidental damage influencing factor according to the damage form and occurrence characteristics of different accidental damage factors. S3: Based on the evaluation rules established in S2, scored binary groups are established for the classifier according to the aircraft configuration, region, maintenance cover and design parameter indicators; S4: Based on the characteristics of the factors influencing accidental damage to the aircraft structure, establish an association matrix of accidental damage factors to evaluate the total accidental damage score of the structure. S5: Determine the structural analysis object and extract key parameters based on the mathematical model of the analysis object; S6: Establish the feature vector of the structural analysis object based on the key parameters extracted in S5; S7: Based on the feature vector extracted in S6 and the scoring rules of each accidental damage influencing factor, the scores of each accidental damage influencing factor of the structural object are determined and analyzed. S8: Based on the scores of each accidental damage influencing factor calculated in S7, the final accidental damage impact is obtained through the correlation matrix.

2. The method as described in claim 1, characterized in that, According to S1, the factors affecting accidental damage are divided into four parts: accidental damage source, residual strength, visibility, and damage propagation sensitivity. The evaluation of accidental damage source describes the probability of the accidental damage factor occurring in the aircraft structure, and is divided into four levels: high, medium, low, and impossible. Residual strength characterizes the maximum load-bearing capacity of the cracked structure and is divided into three levels: high, medium, and low. Visibility is used to describe and analyze the maintainability of structural components and is divided into three levels: good, medium, and bad. Damage propagation sensitivity should be assessed based on stress level and material properties, reflecting the structure's performance when damage and stress are combined, and is divided into three levels: insensitive, moderately sensitive, and sensitive.

3. The method as described in claim 1, characterized in that, In S2, a list of influencing factors is compiled based on the aircraft's operational characteristics, structural features, and the damage modes of accidental damage influencing factors. The list includes all factors that affect the assessment of accidental damage, and specific evaluation rules are given for the influencing factors in the list.

4. The method as described in claim 1, characterized in that, In S3, based on the evaluation rules of accidental damage influencing factors, combined with the aircraft configuration, area, maintenance access cover and design parameter indicators, the evaluation rules are digitized to form a discrimination vector; The discriminant vector is constructed as follows: in: , , The SSI number indicates the subsystem or sub-subsystem to which the SSI belongs, as well as the sequential number of the structural item. , , , These are the positional parameters of the structure being analyzed, used to describe the location of the structural component within the frame, stringer, or rib of the aircraft. When the structural component being analyzed is located in the fuselage... , , , This indicates the frame and stringer where the structural components are located; The parameters represent the internal and external parameters of the structural components. The parameters are set according to whether the structural component is external. The parameter of the outer surface of the skin is 1, the parameter of the inner surface of the skin and the stringer is 2, and so on. These are shape parameters, arranged according to the size of the structural components; , , These are the visibility parameters, strength parameters, crack propagation parameters, and corrosion protection parameters of the structural components, which are given in the aircraft design documents. If any parameter is uncertain, it is set to 0. Based on the scoring rules, a binary tuple is formed by assigning a score to the discriminant vector. ; This indicates the score under the corresponding scoring rules.

5. The method as described in claim 1, characterized in that, Based on the characteristics of the factors influencing accidental damage, a correlation matrix of accidental damage factors is established, which is used to calculate the final total level of accidental structural damage.

6. The method as described in claim 1, characterized in that, The analysis object is determined, including both metallic and non-metallic structures. Key parameters are extracted from the mathematical model of the analysis object, including one or more of the following: shape, assembly relationship, material, and protective measures.

7. The method as described in claim 1, characterized in that, The key parameters of the analysis object are digitized, transforming text parameters into numerical parameters and forming a feature vector with the same dimension as the discriminant vector formed by the scoring rules.

8. The method as described in claim 1, characterized in that, For all accidental damage factors, the nearest neighbor classifier automatically scores them. The nearest neighbor classifier judges the input feature vector by calculating the weighted distance between the feature vector and the discriminant vector. It classifies the input feature vector according to the principle of minimum distance and gives the score of each accidental damage factor of the analyzed structure. The criteria for judgment are as follows: , , in, For belonging to the feature vector All discriminant vector samples within the nearest neighbor region, For sample weights, For feature vectors and belonging to The The distance between each feature vector. The weight matrix is ​​a diagonal matrix, representing... The weight of each component in the vector; for different accidental damage factors, different weight matrices are set according to the description in their scoring rules, based on the meaning represented by the components in the feature vector.

9. The method as described in claim 1, characterized in that, Observation vector Each vector in the equation has a different meaning. Furthermore, based on the characteristics of the structural components and the corresponding data, relevant rules need to be established when calculating distances; position parameters. , This indicates the frame in which the structure is located, forming a range. shape parameters This represents a point; the distance calculation rules are as follows: Rule 1: If or ,make or Rule 2: If ,make .

10. The method as described in claim 1, characterized in that, The scores of all accidental damage factors assessed by the comprehensive structural analysis object are calculated using a correlation matrix to evaluate the final impact of accidental structural damage.

Images