Aero seat production and processing online detection control system

Abstract

The invention belongs to the technical field of seat production and processing, and particularly relates to an online detection control system for aviation seat production and processing, which acquires real-time strain data of a seat metal frame in an aviation load simulation state through an embedded strain gauge array, performs vibration and noise separation processing on the real-time strain data, and obtains the real-time strain data. Constructing a two-dimensional stress field time series data set, mapping the two-dimensional stress field time series data set into microdefect growth trend characteristics based on a material fatigue damage judgment rule, and determining the microdefect growth trend characteristics according to a comparison result of the microdefect growth trend characteristics and a preset critical damage threshold value. The laser positioning device is triggered to mark the risk structural points of the seat metal frame and carry out graded early warning, real-time monitoring and future trend prediction of fatigue degradation of the aero seat metal frame material in the dynamic load state are achieved, early defect damage signals are effectively and accurately captured, and the production cost and airworthiness risk of the aero seat are greatly reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of seat production and processing, and specifically relates to an online detection and control system for the production and processing of aviation seats. Background Art

[0002] Aircraft seats are critical passenger equipment for both civil and military aircraft. Their performance is directly linked to passenger safety, airworthiness compliance, and the overall flight experience. Under the strict safety standards of the aviation industry, inspection accuracy during the production and processing stages is a key factor in determining product quality.

[0003] The metal frame of an airline seat serves as the core support structure, bearing the weight of passengers and resisting flight turbulence and emergency impacts. Its fatigue damage directly determines the seat's structural lifespan and safety margin. In actual service, the frame must withstand cyclical overloads during takeoff and landing, high-frequency vibrations caused by air turbulence, and impact loads during emergency evacuation. These factors can lead to fatigue damage mechanisms within the metal material, such as microcrack propagation and grain slip.

[0004] However, existing technologies for fatigue damage detection of seat metal frames have significant defects. Specifically, existing detection methods only focus on the static geometric dimensions and welding strength of the frame, such as detecting surface defects through ultrasonic testing. They lack the ability to monitor and predict trends of material fatigue degradation under dynamic loads, and it is difficult to capture early micro-damage signals induced by lattice slip. As a result, when the seat is in service and defects are detectable, the structure often enters a period of accelerated damage expansion, which greatly increases the cost of seat replacement and airworthiness risk. Summary of the Invention

[0005] In order to overcome the shortcomings of the background technology, an embodiment of the present invention provides an online detection and control system for the production and processing of aviation seats, which can effectively solve the problems involved in the above-mentioned background technology.

[0006] The purpose of the present invention can be achieved through the following technical solutions: An online detection and control system for the production and processing of aviation seats, including: a strain array acquisition module, a stress field construction module, a defect evolution mapping module and a risk positioning module.

[0007] The strain array acquisition module is connected to the stress field construction module, the stress field construction module is connected to the defect evolution mapping module, and the defect evolution mapping module is connected to the risk location module.

[0008] The strain array acquisition module collects real-time strain data of the seat metal frame under aviation load simulation conditions through an embedded strain gauge array.

[0009] The stress field construction module performs vibration noise separation on real-time strain data and constructs a two-dimensional stress field time series dataset.

[0010] The defect evolution mapping module maps the two-dimensional stress field time series data set into microscopic defect growth trend characteristics based on material fatigue damage judgment rules.

[0011] The risk positioning module triggers the laser positioning device to mark the risky structural points of the seat metal frame and issue graded warnings based on the comparison results of the growth trend characteristics of microscopic defects with the preset critical damage threshold.

[0012] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: (1) The present invention abandons the limitation of the existing static geometric detection that only focuses on the structural morphology, and uses the embedded strain gauge array to capture the dynamic strain data under the aviation load simulation working condition in real time, which can accurately reflect the mechanical response of the seat metal frame during the actual stress process, filling the technical gap that static detection cannot obtain dynamic stress changes.

[0013] (2) The present invention associates macroscopic stress deformation with microscopic defects, maps the two-dimensional stress field time series data set into microscopic defect growth trend characteristics based on the material fatigue damage judgment rule, continuously predicts defect changes based on the current aviation load simulation state, and transforms defect identification from post-detection to pre-prediction, providing a digital decision-making basis for aviation seat production safety assessment.

[0014] (3) The present invention triggers the laser positioning device to mark the risk structure points of the seat metal frame and conducts graded warnings, thereby helping to improve the rapid fault location specifications in the aviation seat metal frame production certification system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention is further described with reference to the accompanying drawings. However, the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other drawings based on the following drawings without creative effort.

[0016] Figure 1 Schematic diagram of module connection of the present invention.

[0017] Figure 2 The figure is a schematic diagram of the layout logic of the embedded strain gauge array in the strain array acquisition module of the present invention.

[0018] Figure 3 This is a logical diagram of the defect evolution mapping module of the present invention. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] Reference Figure 1 As shown, the present invention provides an online detection and control system for the production and processing of aviation seats, including: a strain array acquisition module, a stress field construction module, a defect evolution mapping module and a risk positioning module.

[0021] The strain array acquisition module is connected to the stress field construction module, the stress field construction module is connected to the defect evolution mapping module, and the defect evolution mapping module is connected to the risk location module.

[0022] The strain array acquisition module collects real-time strain data of the seat metal frame under aviation load simulation state through the embedded strain gauge array.

[0023] Reference Figure 2 As shown, in a preferred embodiment of the present invention, the layout method of the embedded strain gauge array includes: obtaining the topological structure information of the seat metal frame, and defining the stress concentration area based on the geometric discontinuity characteristics of the seat metal frame and the key nodes of the main force transmission path.

[0024] It should be noted that the above-mentioned geometric discontinuity features include hole edges, concave corners, weld toes, and cross-sectional mutation areas, and the key nodes of the main force transmission path include load application points, constraint points, and component intersection points.

[0025] The continuous arc segment where the curvature change gradient of the center line of each load-bearing component in the metal frame of the seat exceeds a preset critical threshold is defined as the curved transition area.

[0026] It should be noted that the method for obtaining the centerline curvature change gradient of each load-bearing component in the above-mentioned metal frame of the seat is: define the line connecting the centroids of the cross-section of the load-bearing component as the centerline, use the existing standard curvature calculation formula to quantify the curvature value of each point on the centerline, construct the curvature function of the centerline and derive the arc length, and use the derivative operation result as the centerline curvature change gradient.

[0027] Micro strain gauge groups are arranged at the weld toe in the stress concentration area and the curvature extreme points in the bending transition area, and each group is arranged in an orthogonal strain variation configuration.

[0028] It should be noted that the above-mentioned orthogonal strain gauge rosette configuration specifically refers to the first strain gauge being axially parallel to the main force direction, the second strain gauge being at an angle of 45° to the first strain gauge, and the third strain gauge being at an angle of 90° to the first strain gauge.

[0029] It should also be noted that the layout position of the above-mentioned embedded strain gauge array is limited to the weld toe in the stress concentration area and the curvature extreme point in the bending transition area based on the failure statistical characteristics of the metal frame of the aviation seat. The weld toe refers to the transition zone between the welding heat-affected zone and the base material. Due to grain coarsening and residual stress concentration, it is easy to become a high-risk area for microcrack initiation. When the curvature extreme point is subjected to alternating bending torque, multi-directional stress superposition is generated, which can easily become an overwork defect area.

[0030] In a preferred embodiment of the present invention, the aviation load simulation process includes: fixing the metal frame of the seat to the load bearing surface of the aviation operation simulation platform.

[0031] Start the simulation process and perform the following test steps in sequence: a) Perform a continuous overload test by applying a constant acceleration load in the seat axial direction for a first preset time to simulate the takeoff climb phase.

[0032] b) Conducting a random vibration test to simulate the turbulent phase of flight by generating multi-directional random vibrations corresponding to the characteristic spectrum of aviation turbulence for a second predetermined duration.

[0033] c) Implement impact load testing, applying transient impacts that meet airworthiness standards along the seat force transmission path to simulate the emergency landing phase.

[0034] It should be noted that the first and second preset durations mentioned above may specifically refer to the typical durations of the take-off and climb phases and the turbulence phases of aviation operations.

[0035] The original strain signals of each strain gauge group are captured in real time during the simulation process.

[0036] The embodiments of the present invention abandon the limitation of existing static geometric detection that only focuses on structural morphology. Through the embedded strain gauge array, dynamic strain data under aviation load simulation conditions is captured in real time, which can accurately reflect the mechanical response of the seat metal frame during the actual stress process, filling the technical gap that static detection cannot obtain dynamic stress changes.

[0037] The stress field construction module performs vibration noise separation processing on the real-time strain data to construct a two-dimensional stress field time series data set.

[0038] In a preferred embodiment of the present invention, the process of constructing the two-dimensional stress field time series data set includes: decomposing the original strain signal of each strain gauge group into a load response component and a vibration noise component based on a preset boundary frequency.

[0039] It should be noted that the core basis for setting the above-mentioned preset demarcation frequency is that the load response component is concentrated in the low-frequency domain, while the vibration noise component is significantly present in the high-frequency domain, which can be obtained through experimental calibration. The specific experimental process is as follows: a preset number of seat metal frame samples to be tested are selected and divided into static group and dynamic group.

[0040] A step-by-step incremental static load is applied to the static group, and the energy cumulative distribution of the load response signal in the low-frequency band is calculated through spectrum analysis. The critical frequency at which the energy proportion exceeds a preset percentage is used as the characteristic low-frequency threshold. The low-frequency band can be exemplified as 0-200 Hz.

[0041] Apply sweep frequency excitation to the dynamic group and record the dynamic strain response spectrum under the excitation at each frequency point. When the noise amplitude increment caused by a certain frequency point exceeds the preset decibel of the base value, the frequency is marked as the starting point of the high-frequency noise.

[0042] The arithmetic median of the characteristic low-frequency threshold and the high-frequency noise starting point is taken as the preset dividing frequency verified by experiments.

[0043] The load response components of each strain gauge group are converted into orthogonal strain data of its arrangement configuration, and the orthogonal strain data are converted into in-plane stress data based on Hooke's law under a plane stress state, including X-direction normal stress, Y-direction normal stress, and shear stress components.

[0044] It should be noted that the conversion of the load response component of each strain gauge group into the orthogonal strain data of its arrangement configuration should be performed according to the following rules: the strain value collected by the first strain gauge is directly assigned as the X-direction normal strain component.

[0045] The strain value collected by the third strain gauge is directly assigned as the positive strain component in the Y direction.

[0046] Calculate twice the strain value collected by the second strain gauge, subtract the sum of the strain values ​​of the first and third strain gauges from it, and the difference is the shear strain component.

[0047] The above-mentioned conversion of the orthogonal strain data into in-plane stress data based on Hooke's law under plane stress state can refer to the following equation: ,in They represent the X-direction normal stress, Y-direction normal stress and shear stress components respectively, They represent the X-direction normal strain, Y-direction normal strain and shear strain components respectively, They respectively represent the preset elastic modulus and Poisson's ratio of the aviation seat metal material.

[0048] According to the layout spatial coordinates of the strain gauge group, the in-plane stress data is mapped to the two-dimensional parameterized plane of the seat metal frame to generate discrete stress points.

[0049] Based on the topological relationship of the force transmission path, surface interpolation is performed on adjacent discrete stress points to generate a continuous stress field.

[0050] The synchronously collected stress field data are stored in time series to form a two-dimensional stress field time series data set.

[0051] The defect evolution mapping module maps the two-dimensional stress field time series data set into microscopic defect growth trend characteristics based on material fatigue damage judgment rules.

[0052] Reference Figure 3 As shown, in a preferred embodiment of the present invention, the two-dimensional stress field time series data set is mapped into micro-defect growth trend characteristics based on the material fatigue damage judgment rule, including: for the in-plane stress component time series data of each discrete stress point in the two-dimensional stress field, the real-time principal stress direction angle is solved by stress tensor transformation and its time domain change interval is recorded to determine the maximum damage action plane of each discrete stress point.

[0053] It should be noted that the specific process of solving the real-time principal stress direction angle through stress tensor transformation includes: taking twice the value of the shear stress component under the current stress state as the numerator, and taking the algebraic difference between the X-direction normal stress component and the Y-direction normal stress component as the denominator.

[0054] When the absolute value of the denominator is greater than 0, the numerator is divided by the denominator to obtain a ratio parameter, an inverse tangent function value is obtained for the ratio parameter, and the obtained angle value is halved to obtain the principal stress direction angle.

[0055] When the denominator is equal to 0 and the numerator is a positive value, the main direction angle is determined to be +45 degrees.

[0056] When the denominator is equal to 0 and the numerator is a negative value, the main direction angle is determined to be -45 degrees.

[0057] When the numerator is equal to 0, it means that there is no shear stress. On this basis, if the normal stress in the X direction is greater than the normal stress in the Y direction, the main direction angle is 0 degrees. If the normal stress in the Y direction is greater than the normal stress in the X direction, the main direction angle is 90 degrees.

[0058] The orthogonal strain data corresponding to each discrete stress point is retrieved, the normal strain component and the shear strain component of the maximum damage action plane are extracted, and the damage value of a single aviation operation cycle of each discrete stress point is calculated.

[0059] It should be noted that the process of obtaining the normal strain component of the maximum damage action plane is as follows: According to the X-direction normal strain component, Y-direction normal strain component and shear strain component in the orthogonal strain data, the formula To obtain, among which is the angle between the normal of the maximum damage action plane and the X-axis.

[0060] The subsequent normal stress components can be obtained by performing the same processing based on the in-plane stress data.

[0061] The number of cycles is counted according to the service conditions of the aircraft model to which the seat metal frame belongs, and linear accumulation is performed in combination with the damage value of the single aviation operation cycle.

[0062] The cumulative damage value is input into a pre-calibrated defect growth rate model, and the micro defect size and expansion direction vector of each discrete stress point are output to form the micro defect growth trend characteristics.

[0063] In a preferred embodiment of the present invention, determining the maximum damage action plane of each discrete stress point includes: obtaining a preset normal vector spatial distribution of a crystal slip system of the aviation seat metal material.

[0064] It should be noted that the above-mentioned crystal slip system is the basic mechanism when crystalline materials undergo plastic deformation. It is composed of slip planes and slip directions on these planes. Its essence is a combination of paths in which the atomic layers slide relative to each other along specific crystal planes and directions under the action of external forces. The crystal slip system of aviation seat metal materials can refer to relevant aviation material standards, or the corresponding content related to aviation seat metal materials in crystallography and materials science journals.

[0065] The principal stress direction angles of the discrete stress points whose angles with the normal vector of the slip system within the time domain variation range are screened to generate a candidate plane set.

[0066] Based on the in-plane stress data of the candidate plane, the normal stress amplitude and the shear stress amplitude are quantified and linearly weighted fused to obtain a composite damage index.

[0067] It should be noted that the specific quantification methods for the above-mentioned normal stress amplitude and shear stress amplitude are consistent. Taking the shear stress amplitude as an example: the shear stress components of all candidate planes are screened, the maximum and minimum values ​​are screened, the difference between the maximum and minimum values ​​is used as the denominator, the difference between the shear stress component of a candidate plane and the minimum value is used as the numerator, and the ratio operation is carried out to obtain the shear stress amplitude of the candidate plane.

[0068] It should also be noted that the distribution weights of the above-mentioned normal stress amplitude and shear stress amplitude can be set according to industry experience, or they can be obtained through a limited number of test data. For example, in the experimental combination of each candidate plane with the maximum damage action plane calibrated, the distribution weights of the normal stress amplitude and the shear stress amplitude are arbitrarily matched, and the contribution of the normal stress amplitude and the shear stress amplitude is determined using regression analysis or logistic regression analysis. Finally, after normalization, the contribution is converted into a weight and its sum is 1.

[0069] The candidate plane corresponding to the maximum composite damage index is selected as the maximum damage action plane.

[0070] In a preferred embodiment of the present invention, calculating the damage value of a single aviation operation cycle for each discrete stress point includes: time-integrating the product of the normal stress component and the normal strain component, and the product of the shear stress component and the shear strain component, respectively, to obtain the normal strain energy density component and the shear strain energy density component.

[0071] The sum of the two is defined as the cyclic integral of the strain energy density, and the pre-calibrated damage transfer function is input to output the single-cycle damage value.

[0072] The damage conversion function is calibrated through material fatigue testing to establish a mapping relationship between the cyclic integral of strain energy density and the dimensionless damage value.

[0073] In a preferred embodiment of the present invention, the process of constructing the pre-calibrated defect growth rate model includes: training the model based on a fatigue-fracture joint test dataset of aviation seat metal materials.

[0074] The mapping relationship between the cumulative damage value and the defect size increment is fitted by a power law function.

[0075] The normal direction of the maximum damage action plane and the direction of the maximum principal stress are fused through the vector synthesis function to output the defect extension direction vector.

[0076] It should be noted that the above power law function can be exemplified by referring to the Paris power law equation.

[0077] The above-mentioned vector synthesis function can calibrate the hybrid weight of the propagation direction based on the observation of crack trajectory under multiaxial loading, so as to perform a linear weighted fusion of the normal direction of the maximum damage action plane and the maximum principal stress direction, where the maximum principal stress direction is defined as the dominant direction based on the maximization of the time-domain integral energy of the principal stress vector.

[0078] The embodiment of the present invention associates macroscopic stress deformation with microscopic defects, maps the two-dimensional stress field time series data set into microscopic defect growth trend characteristics based on material fatigue damage judgment rules, continuously predicts defect changes based on the current aviation load simulation state, and transforms defect identification from post-detection to pre-prediction, providing a digital decision-making basis for aviation seat production safety assessment.

[0079] The risk positioning module triggers the laser positioning device to mark the risk structural points of the seat metal frame and issue a graded warning based on the comparison results of the micro-defect growth trend characteristics with the preset critical damage threshold.

[0080] In a preferred embodiment of the present invention, the comparison process of the micro-defect growth trend characteristics with the preset critical damage threshold includes: mapping the discrete stress point coordinates of the two-dimensional parameterized plane to the three-dimensional physical coordinates of the seat metal frame.

[0081] If the microscopic defect size of a discrete stress point exceeds the permissible threshold of the safety defect size of its physical location, the three-dimensional physical coordinate position of the discrete stress point shall be regarded as a first-level risk structural point.

[0082] If the defect size does not exceed the permissible threshold but the angle between the defect extension direction vector and the normal plane of the adjacent component exceeds the preset standard angle, the three-dimensional entity coordinate position of the discrete stress point is regarded as a secondary risk structural point.

[0083] In a preferred embodiment of the present invention, the graded warning includes the following contents: triggering the laser positioning device to mark the first-level risk structural point of the seat metal frame with a red laser, and synchronously sending a thermal repair processing instruction to the repair execution terminal.

[0084] The secondary risk structural points of the seat metal frame are marked with a yellow laser, and micro-defect suppression instructions are simultaneously sent to the process adjustment terminal.

[0085] The embodiment of the present invention triggers a laser positioning device to mark risky structural points of the seat metal frame and issues graded warnings, thereby helping to improve the rapid fault location specifications in the aviation seat metal frame production certification system.

[0086] The above formulas are all dimensionless and numerical calculations. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0087] The above embodiments may be implemented in whole or in part through software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments may be implemented in whole or in part in the form of a computer program product.

[0088] Those skilled in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0089] In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0090] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

[0091] Finally, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An online detection and control system for the production and processing of aviation seats, characterized in that: include: The strain array acquisition module uses an embedded strain gauge array to collect real-time strain data of the seat metal frame under aviation load simulation conditions; The stress field construction module performs vibration noise separation on real-time strain data to construct a two-dimensional stress field time series data set; A defect evolution mapping module maps the two-dimensional stress field time series data set into microscopic defect growth trend characteristics based on material fatigue damage judgment rules; The risk positioning module triggers the laser positioning device to mark the risky structural points of the seat metal frame and issue graded warnings based on the comparison results of the growth trend characteristics of microscopic defects with the preset critical damage threshold.

2. The on-line detection and control system for manufacturing and processing aircraft seats according to claim 1, characterized in that: The method for arranging the embedded strain gauge array includes: obtaining topological structural information of the metal frame of the seat, and defining stress concentration areas based on geometric discontinuity features and key nodes of a main force transmission path of the metal frame of the seat; Defining a continuous arc segment where the centerline curvature gradient of each load-bearing member in the metal frame of the seat exceeds a preset critical threshold as a curved transition area; Micro strain gauge groups are arranged at the weld toe in the stress concentration area and the curvature extreme points in the bending transition area, and each group is arranged in an orthogonal strain rosette configuration.

3. The on-line detection and control system for manufacturing and processing aircraft seats according to claim 1, characterized in that: The aviation load simulation process includes: Fix the metal frame of the seat to the load-bearing surface of the aviation operation simulation table; Start the simulation process and perform the following test steps in sequence: a) Conduct a continuous overload test by applying a constant acceleration load in the axial direction of the seat for a first predetermined period of time to simulate the takeoff climb phase; b) conducting a random vibration test to simulate the turbulent phase of flight by generating multi-directional random vibrations corresponding to the characteristic spectrum of aviation turbulence for a second predetermined duration; c) Conducting shock load tests, applying transient shocks that meet airworthiness standards along the seat's force transmission path to simulate an emergency landing; The original strain signals of each strain gauge group are captured in real time during the simulation process.

4. The on-line detection and control system for manufacturing and processing aircraft seats according to claim 3 is characterized by: The process of constructing the two-dimensional stress field time series dataset includes: Based on the preset boundary frequency, the original strain signal of each strain gauge group is decomposed into a load response component and a vibration noise component; Converting the load response components of each strain gauge group into orthogonal strain data of its arrangement configuration, and converting the orthogonal strain data into in-plane stress data based on Hooke's law under a plane stress state, including X-direction normal stress, Y-direction normal stress, and shear stress components; Mapping the in-plane stress data to a two-dimensional parameterized plane of the seat metal frame based on the spatial coordinates of the strain gauge group to generate discrete stress points; Based on the topological relationship of the force transmission path, surface interpolation is performed on adjacent discrete stress points to generate a continuous stress field; The synchronously collected stress field data are stored in time series to form a two-dimensional stress field time series data set.

5. The on-line detection and control system for manufacturing and processing aircraft seats according to claim 4, characterized in that: The mapping of the two-dimensional stress field time series data set into microscopic defect growth trend characteristics based on the material fatigue damage judgment rule includes: For the time series data of the in-plane stress component of each discrete stress point in the two-dimensional stress field, the real-time principal stress direction angle is solved by stress tensor transformation and its time domain variation interval is recorded to determine the maximum damage action plane of each discrete stress point; Recalling the orthogonal strain data corresponding to each discrete stress point, extracting the normal strain component and the shear strain component of the maximum damage action plane, and calculating the damage value of a single aviation operation cycle for each discrete stress point; The number of cycles is calculated based on the service conditions of the aircraft model to which the seat metal frame belongs, and linear accumulation is performed in combination with the damage value of the single aviation operation cycle; The cumulative damage value is input into a pre-calibrated defect growth rate model, and the micro defect size and expansion direction vector of each discrete stress point are output to form the micro defect growth trend characteristics.

6. The on-line detection and control system for manufacturing and processing aircraft seats according to claim 5, characterized in that: Determining the maximum damage action plane of each discrete stress point includes: Obtain the spatial distribution of the preset normal vector of the crystal slip system of the aviation seat metal material; Screening the principal stress direction angles of discrete stress points whose angles with the normal vector of the slip system are less than a preset critical angle within the time domain variation range of the principal stress direction angles, and generating a candidate plane set; Based on the in-plane stress data of the candidate plane, the normal stress amplitude and the shear stress amplitude are quantified and linearly weighted fused to obtain a composite damage index; The candidate plane corresponding to the maximum composite damage index is selected as the maximum damage action plane.

7. The on-line detection and control system for manufacturing and processing aircraft seats according to claim 5, characterized in that: The calculation of the damage value of a single aviation operation cycle at each discrete stress point includes: The product of the normal stress component and the normal strain component, and the product of the shear stress component and the shear strain component are respectively integrated over time to obtain the normal strain energy density component and the shear strain energy density component; The sum of the two is defined as the cyclic integral of strain energy density, and the pre-calibrated damage transfer function is input to output the single-cycle damage value; The damage conversion function is calibrated through material fatigue testing to establish a mapping relationship between the cyclic integral of strain energy density and the dimensionless damage value.

8. The on-line detection and control system for manufacturing and processing aircraft seats according to claim 5, characterized in that: The process of constructing the pre-calibrated defect growth rate model includes: The model is trained based on a fatigue-fracture joint test dataset of aviation seat metal materials; The mapping relationship between the cumulative damage value and the defect size increment is fitted by a power law function; The normal direction of the maximum damage action plane and the direction of the maximum principal stress are fused through the vector synthesis function to output the defect extension direction vector.

9. The on-line detection and control system for manufacturing and processing aircraft seats according to claim 5, characterized in that: The comparison process of the micro defect growth trend characteristics with the preset critical damage threshold includes: Mapping the coordinates of discrete stress points on the two-dimensional parameterized plane to the three-dimensional solid coordinates of the seat metal frame; If the microscopic defect size of a discrete stress point exceeds the permissible threshold of the safety defect size of its physical location, the three-dimensional physical coordinate position of the discrete stress point shall be regarded as a first-level risk structural point; If the defect size does not exceed the permissible threshold but the angle between the defect extension direction vector and the normal plane of the adjacent component exceeds the preset standard angle, the three-dimensional entity coordinate position of the discrete stress point is regarded as a secondary risk structural point.

10. The on-line detection and control system for manufacturing and processing aircraft seats according to claim 9, characterized in that: The graded warning includes the following contents: Trigger the laser positioning device to mark the first-level risk structural points of the seat metal frame with a red laser, and simultaneously send a thermal repair processing instruction to the repair execution terminal; The secondary risk structural points of the seat metal frame are marked with a yellow laser, and micro-defect suppression instructions are simultaneously sent to the process adjustment terminal.

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