A full machine static test loading method and device based on force transmission path

Abstract

The application discloses a full-machine static test loading method and device based on a force transmission path, and the method comprises the following steps: applying an aerodynamic load to a finite element model of a test object to perform statics simulation and obtaining a simulation result; extracting a main force transmission path and internal force values of each section on the main force transmission path based on the simulation result; dividing the main force transmission path into a plurality of stress sub-zones based on the distribution characteristics of the internal force values; constructing a position optimization model by taking the positions of loading points in the stress sub-zones as design variables and taking the sub-zone boundaries as constraints, and solving the position optimization model to obtain the optimal positions of the loading points; applying loads at the optimal positions to obtain a distribution factor matrix, constructing a load optimization model in combination with the simulation result of a concerned part, and solving the load optimization model to obtain the optimal loads of the loading points. The method solves the problem that the prior art can only optimize the load size on the basis of fixed loading points and initial load distribution, and the reliability and test precision of the full-machine static test are insufficient, and the reliability and precision of the full-machine static test are improved.

Description

Technical Field

[0001] This application relates to the field of aerospace engineering structural testing technology, and in particular to a method and apparatus for static testing of the entire aircraft based on the force transmission path. Background Technology

[0002] Static testing of an entire aircraft is a crucial ground test used in aircraft development to verify the strength and stiffness of the airframe structure. The results directly impact the safety and reliability of the aircraft. Aircraft experience complex and variable loads during actual flight; therefore, static testing must realistically reproduce these load conditions to accurately assess the structure's load-bearing capacity. However, traditional static testing methods rely heavily on manual experience and simplified calculations, making it difficult to simulate the load distribution under real flight conditions. Furthermore, the layout of loading points in traditional static testing lacks scientific basis, resulting in poor load transfer and an inability to accurately reproduce the true stress state of different structural parts. Ultimately, this leads to significant deviations between test data and actual operating conditions, hindering accurate assessment of aircraft structural performance and failing to meet the high-precision design and testing requirements of modern aircraft.

[0003] Currently, there are relevant technical solutions (such as the patent with publication number CN116167150B) that propose improved approaches to the load distribution problem in the static test of the entire aircraft. This solution pre-sets the spatial location of the loading points and the initial load distribution as fixed input parameters. The overall technical approach revolves around load value optimization, relying on mathematical iterative algorithms to allocate and optimize the load size at each loading point, thereby completing the loading settings for the static test of the entire aircraft.

[0004] This technical solution relies on a crucial assumption: the pre-set loading point locations are already reasonable, effectively simulating the actual stress state of the structure, and the basic form of the load distribution is already determined, requiring only numerical adjustments. However, in practical engineering, whether the loading points are located on the main force transmission path and whether they can accurately transmit the spatial load distribution during actual flight are often fundamental factors affecting test accuracy. This technical solution fails to optimize the loading point locations and does not incorporate the load distribution as a variable into the design process. Therefore, it is still possible for loading points to deviate from the main force transmission path, causing load transmission distortion; or for the load distribution to fail to match the non-uniform, multi-directional characteristics of actual flight conditions; or for the stress state of key structural components to fail to accurately reflect the actual stress situation, leading to unreliable evaluation results of aircraft structural performance. Summary of the Invention

[0005] This application provides a loading method and apparatus for a full-aircraft static test based on the force transmission path, which solves the problem that the existing technology can only optimize the load size based on a fixed loading point and initial load distribution, resulting in insufficient reliability and test accuracy of the full-aircraft static test.

[0006] In a first aspect, embodiments of this application provide a method for loading a static test of an entire aircraft based on a force transmission path, comprising: applying aerodynamic loads to a finite element model of the test object, performing static simulation, and obtaining simulation results; extracting the main force transmission path and the internal force values ​​of each section on the main force transmission path based on the simulation results; dividing the main force transmission path into multiple stress zones based on the distribution characteristics of the internal force values ​​of each section; constructing a position optimization model with the position of the loading point in each stress zone as a design variable and the zone boundary as a constraint to solve for the optimal position of the loading point in each stress zone; applying loads to the optimal positions of each loading point to obtain the allocation factor matrix of the part of interest, and constructing a load optimization model in combination with the simulation results corresponding to the part of interest to solve for the optimal load of each loading point.

[0007] In conjunction with the first aspect, in one possible implementation, the simulation results include stress data, strain data, internal force values, and the total load and total torque of the test object.

[0008] In conjunction with the first aspect, in one possible implementation, the step of extracting the main force transmission path and the internal force values ​​of each section along the main force transmission path based on the simulation results includes: generating a stress cloud map based on the stress data in the simulation results, extracting the main force transmission path from the stress cloud map; cutting multiple sections along the main force transmission path at preset section distances, and extracting the internal force values ​​of each section; wherein the internal force values ​​include bending moment, shear force, and torque.

[0009] In conjunction with the first aspect, in one possible implementation, dividing the main force transmission path into multiple force-bearing zones based on the distribution characteristics of the internal force values ​​of each cross section includes: constructing corresponding internal force vectors based on the internal force values ​​of each cross section; determining the vector angle between the internal force vectors of two adjacent cross sections; determining the zone boundary based on the variation characteristics of the vector angle; and dividing the main force transmission path into multiple continuous force-bearing zones based on the zone boundary.

[0010] In conjunction with the first aspect, in one possible implementation, determining the partition boundary based on the changing characteristics of the vector angle includes: determining the location where the vector angle undergoes a sudden change as the partition boundary.

[0011] In conjunction with the first aspect, in one possible implementation, determining the partition boundary based on the variation characteristics of the vector angle further includes: retaining the partition boundary when the number of partition boundaries meets a preset number range; filtering out multiple partition boundaries based on the vector angle when the number of partition boundaries exceeds the upper limit of the preset number range so that the number of partition boundaries meets the preset number range; and generating new partition boundaries when the number of partition boundaries is less than the lower limit of the preset number range.

[0012] In conjunction with the first aspect, in one possible implementation, the location optimization model takes minimizing the comprehensive internal force index of the cross section as the objective function; wherein the comprehensive internal force index of the cross section is determined by the internal force value of the cross section.

[0013] In conjunction with the first aspect, in one possible implementation, applying loads to the optimal positions of each loading point to obtain the allocation factor matrix of the area of ​​interest, and constructing a load optimization model based on the simulation results corresponding to the area of ​​interest, and solving for the optimal load at each loading point, includes: calibrating the optimal positions of all loading points in the finite element model of the test object; applying unit loads to each loading point sequentially and then extracting the response data of the area of ​​interest to obtain the corresponding allocation factor matrix; extracting strain data of the area of ​​interest, as well as the total load and total torque of the test object from the simulation results; using the loads at each loading point as design variables, determining the objective function based on the allocation factor matrix, the loads at each loading point, and the strain data, and constructing a load optimization model with constraints including the range of the load loading device, the conservation of the total load of the test object, and the conservation of the total torque; and solving the load optimization model to obtain the optimal load corresponding to each loading point.

[0014] Secondly, this application provides a static test loading device for the entire aircraft based on the force transmission path, comprising: a simulation module for applying aerodynamic loads to the finite element model of the test object, performing static simulation, and obtaining simulation results; an identification module for extracting the main force transmission path and the internal force values ​​of each section on the main force transmission path based on the simulation results; a partitioning module for dividing the main force transmission path into multiple force-bearing partitions based on the distribution characteristics of the internal force values ​​of each section; a position solving module for constructing a position optimization model with the position of the loading point in each force-bearing partition as the design variable and the partition boundary as the constraint, to solve for the optimal position of the loading point in each force-bearing partition; and a load solving module for applying loads to the optimal positions of each loading point to obtain the allocation factor matrix of the part of interest, and constructing a load optimization model in combination with the simulation results corresponding to the part of interest, to solve for the optimal load of each loading point.

[0015] Thirdly, embodiments of this application provide an apparatus comprising: a processor; a memory for storing processor-executable instructions; wherein, when the processor executes the executable instructions, it implements the method as described in the first aspect or any possible implementation of the first aspect.

[0016] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: This application's embodiments, by identifying the main force transmission path, can accurately locate the core path of load transfer, ensuring that the loading points are placed in the most critical areas of structural stress, thus preventing load transfer distortion caused by loading points deviating from the main force transmission path from the source. By dividing the stress zone based on the internal force value distribution characteristics, the internal force distribution characteristics within each zone can be made more consistent, providing clear zone boundaries and targeted optimization directions for subsequent loading point location optimization, avoiding cross-regional force interference. The location optimization model, constrained by the zone boundaries, can maximize the matching of the stress requirements of the main force transmission path, further improving the accuracy of load transfer. Based on the optimal location, a load optimization model is constructed, and combined with the allocation factor matrix, simulation results of the parts of interest, and multiple constraints, the optimal load for each loading point can be accurately output, making the experimental loading state highly consistent with the structural stress state under real flight conditions. This effectively solves the problem that existing technologies can only optimize the load size based on fixed loading points and initial load distribution, resulting in insufficient reliability and accuracy of full-aircraft static tests, significantly improving the reliability and accuracy of full-aircraft static tests, and providing scientific and efficient technical support for the accurate assessment of the structural strength and stiffness of modern aircraft. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart of a full-machine static test loading method based on force transmission path provided for embodiments of this application; Figure 2 A schematic diagram of a full-machine static test loading device based on force transmission path provided in this application embodiment; Figure 3 Example diagrams for extracting the main force transmission path from stress cloud diagrams provided in this application embodiment; Figure 4 Example diagram of the included angle of vectors provided in the embodiments of this application; Figure 5An example diagram of the partition boundary provided in an embodiment of this application. Detailed Implementation

[0019] 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, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0020] The following description of some technologies involved in the embodiments of this application is provided to aid understanding and should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this application. Similarly, for clarity and brevity, some descriptions of well-known functions and structures are omitted in the following description.

[0021] Figure 1 This is a flowchart of a full-machine static test loading method based on force transmission path provided in an embodiment of this application, including steps 101 to 105. Wherein, Figure 1 This is merely one execution order shown in the embodiments of this application, and does not represent the only execution order of a full-machine static test loading method based on force transmission path. Where the final result can be achieved, Figure 1 The steps shown can be performed in parallel or in reverse order.

[0022] Step 101: Apply aerodynamic loads to the finite element model of the test object, perform static simulation, and obtain simulation results. In this embodiment, the simulation results include stress data, strain data, internal force values, and the total load and total moment of the test object.

[0023] Specifically, a finite element model of the test object is first constructed. A three-dimensional digital model is established according to the actual geometric parameters of the test object. A uniformly sized computational mesh is divided according to the simulation accuracy requirements. At the same time, the structural material properties, component constraints, and contact relationships are entered to complete the preprocessing of the finite element model. After the finite element model is completed, aerodynamic loads simulating actual working conditions are applied to the finite element model, and static simulation calculations are initiated. After the displacement and stress convergence conditions are met, the simulation results are obtained. The stress data corresponding to each position is extracted from the simulation results for subsequent extraction of the main force transmission path and stress state analysis. Simultaneously, the external loads at all loading points on the finite element model are calculated using global integral superposition. Through the equivalent conversion method of the spatial force system, the total load and total moment of the finite element model structure under the current working conditions are obtained.

[0024] Step 102: Extract the main force transmission path and the internal force values ​​of each section along the main force transmission path based on the simulation results. In this embodiment, a stress cloud map is generated based on the stress data in the simulation results, and the main force transmission path is extracted from the stress cloud map; multiple sections are cut along the main force transmission path at preset section distances, and the internal force values ​​of each section are extracted; wherein, the internal force values ​​include bending moment, shear force, and torque.

[0025] Specifically, the stress data is extracted from the simulation results obtained in step 101, the stress data is imported using the simulation post-processing tool, and a stress contour plot is generated according to standard visualization rules. For example... Figure 3 As shown, by combining the stress concentration distribution pattern and load transfer direction of the stress cloud diagram, the main force transmission path of the test object structure is identified, the spatial coordinates of the main force transmission path are extracted, and the extension trajectory and spatial distribution characteristics of the main force transmission path are fully recorded.

[0026] The cross-sectional distance can be flexibly adjusted according to the size of the test object and the complexity of the stress. In this application, the maximum value of the finite element mesh size is selected as the cross-sectional distance. Along the extension direction of the main force transmission path, several continuous cross-sections are cut at equal intervals according to the cross-sectional distance. The internal force values ​​of each cross-section, including bending moment, shear force and torque, are read by the finite element post-processing tool, and the maximum values ​​of bending moment, shear force and torque are selected.

[0027] Step 103: Divide the main force transmission path into multiple force zones based on the distribution characteristics of the internal force values ​​at each cross-section. In this embodiment, a corresponding internal force vector is constructed based on the internal force values ​​at each cross-section; the vector angle between the internal force vectors of two adjacent cross-sections is determined, and the zone boundary is determined based on the variation characteristics of the vector angle; the main force transmission path is divided into multiple continuous force zones based on the zone boundaries. Specifically, determining the zone boundaries based on the variation characteristics of the vector angle includes: determining the location where the vector angle changes abruptly as the zone boundary.

[0028] Specifically, the internal force values ​​of each section obtained in step 102 are used to construct the corresponding internal force vectors. The vector angle between the internal force vectors of two adjacent sections is calculated. The partition boundary is determined based on the variation law of the vector angle. Then, the main force transmission path is divided into multiple continuous force partitions through the partition boundary. Among them, the internal force vector is a characteristic vector formed by the combination of multiple internal force values ​​of a single section, which is used to characterize the comprehensive stress state of the section; the vector angle is used to reflect the degree of change in the stress state between adjacent sections.

[0029] Furthermore, for each section along the main force transmission path, the bending moment, shear force, and torque corresponding to that section are extracted and constructed into independent internal force vectors according to a fixed combination rule. For any section i along the main force transmission path, its internal force vector is as follows: , In the formula, M represents the internal force vector of section i. i Q represents the bending moment at section i. i T represents the shear force at section i. i M represents the torque at section i. max Q max T max These represent the maximum values ​​of bending moment, shear force, and torque at all sections along the main force transmission path. , , The normalized bending moment, shear force, and torque of section i are represented, with values ​​ranging from [0,1].

[0030] Calculate the vector angle between the internal force vectors of two adjacent sections one by one. The vector angle between the internal force vectors of adjacent sections is as follows: Figure 4 As shown. Calculate the cosine of the angle between the internal force vectors of adjacent sections, as follows: , , In the formula, The vector angle between the internal force vectors of section i and section i+1 is represented by , and n represents the number of sections on the main force transmission path.

[0031] The location of abrupt changes in the stress state of a cross section is determined by the numerical change in the angle between vectors (here, the change in the cosine value of the angle between vectors represents the numerical change in the angle between vectors), and the location where the stress state changes significantly is designated as the partition boundary. In this application, the number of partition boundaries can be flexibly adjusted according to the actual number of experimental loading devices and the complexity of the structural stress. After determining all partition boundaries, each partition boundary is used as a dividing node to segment the entire main force transmission path, ultimately resulting in several independent and relatively stable continuous segments, each segment being a stress partition.

[0032] In this embodiment of the application, the partition boundary is determined based on the variation characteristics of the vector angle. Further steps include: retaining the partition boundary when the number of partition boundaries meets a preset number range; selecting multiple partition boundaries based on the vector angle when the number of partition boundaries exceeds the upper limit of the preset number range, so that the number of partition boundaries meets the preset number range; and generating new partition boundaries when the number of partition boundaries is less than the lower limit of the preset number range.

[0033] Specifically, after initially determining the partition boundaries based on the changing characteristics of the vector angle, the partition boundaries can be further filtered and adjusted using a preset quantity range, as follows: When the number of partition boundaries falls within the preset quantity range, it indicates that the current partition scale is suitable for the test requirements and no additional changes are needed; all current partition boundaries are directly retained. When the number of partition boundaries exceeds the upper limit of the preset quantity range, it indicates that the partition division is too fine and the number of partitions is too large. In this case, all partition boundaries are sorted in descending order according to the cosine value of the vector angle, prioritizing the retention of partition boundaries with larger cosine values ​​of the vector angle and more significant changes in the stress state, and successively eliminating secondary partition boundaries until the number of partition boundaries meets the preset quantity range. When the number of partition boundaries is less than the lower limit of the preset quantity range, it indicates that the original partition division is too general and cannot meet the loading deployment requirements. In this case, the currently defined partition boundaries are no longer used. Based on the values ​​within the preset quantity range, the main force transmission path is evenly divided along its extension direction, dividing the main force transmission path into continuous segments that meet the preset quantity range. The dividing nodes of each segment are the newly generated partition boundaries, thus completing the correction and reconstruction of the partition boundaries. The preset quantity range (exemplarily set to [3,8]) is a reasonable range of the number of partitions pre-set in combination with the number of loading devices used in the full-machine static test and the test conditions.

[0034] For example, when the vector angle between the internal force vectors of section i and section i+1 satisfy ,and When the stress state changes abruptly, section i is retained as the partition boundary, that is, the location where the stress state changes abruptly is taken as the partition boundary.

[0035] When the number of partition boundaries k is within the preset number range [N] min N max Within this range, retain the current partition boundaries and divide the main force transmission path into k+1 consecutive force-bearing partitions; when the number of partition boundaries k is greater than the upper limit N of the preset number range... max When the cosine values ​​of the included angles of the vectors corresponding to the cross-sections are sorted in descending order, the top N values ​​are selected. max Using each cross section as a partition boundary, the main force transmission path is divided into N sections. max +1 consecutive stress zones; when the number of zone boundaries k is less than the lower limit N of the preset quantity range. min At that time, the main force transmission path is divided into N equal parts according to the path length. min +1 consecutive stress zones, such as Figure 5 As shown.

[0036] Those skilled in the art should recognize that the partition boundaries in this application are determined by the inflection points where the internal force values ​​(characterized by the cosine of the angle between the corresponding internal force vectors) change along the main force transmission path. When the load conditions change, the positions of the main force transmission path and the partition boundaries can be adaptively adjusted accordingly, truly reflecting the dynamic changes in force distribution. Furthermore, this application determines the internal force values ​​based on the simulation results of static simulation using a finite element model, without relying on the geometric characteristics of the structural model (such as rib positions, frame positions, etc.). When the structural layout of the test object changes, as long as the distribution characteristics of the main force transmission path and internal force values ​​remain unchanged, the partitioning results will remain unchanged, eliminating the need for repeated iterations. Finally, this application divides the partition boundaries at the force inflection points. When determining the location of the loading point, the location of the partition boundary can be avoided, ensuring that the loading point is located in a stable force-bearing region within the partition, rather than at the inflection point where internal forces change drastically, effectively avoiding the risk of local overload or stress concentration.

[0037] Step 104: Using the location of the loading point within the stress zone as the design variable and the zone boundary as the constraint, construct a location optimization model to solve for the optimal location of the loading point within each stress zone. The location optimization model uses minimizing the comprehensive internal force index of the cross section as the objective function; the comprehensive internal force index of the cross section is determined by the internal force value of the cross section.

[0038] Specifically, independent optimization calculations are performed for each stress zone divided in step 103. First, design variables are defined, using the positions (two-dimensional or three-dimensional spatial coordinates) of the loading points to be deployed within each stress zone as the design variables for this optimization. The positions of the loading points can be freely adjusted within the corresponding stress zone. Second, constraints are set, using the two side boundaries of the current stress zone as position constraints to limit the coordinate range of the loading points, ensuring that the loading points are always placed within the corresponding stress zone and do not exceed the zone boundaries. Based on this, the objective function is determined. In this embodiment, the minimum comprehensive internal force index of the cross section is used as the optimization objective. The comprehensive internal force index of the cross section is calculated by combining the bending moment, shear force, torque, and other internal force values ​​of the cross section, which can objectively characterize the stress state of the cross section corresponding to different loading point positions. After configuring the design variables, constraints, and objective function, a position optimization model is constructed. An appropriate optimization algorithm is selected to iteratively solve the position optimization model. The position of the loading point is continuously adjusted and the corresponding comprehensive internal force index of the cross section is calculated until the index reaches the minimum and the result converges. At this time, the position of the loading point is the optimal position in the stress zone. The solution of all stress zones is completed in sequence to obtain the optimal position of all loading points.

[0039] For example, the objective function of the location optimization model is as follows: , The constraints are: , In the formula, Indicates the comprehensive internal force index of the cross section. This represents the bending moment at the section located at the loading point x. This represents the reference value of the bending moment within the stress zone, that is, the maximum value of the bending moment at all sections within the stress zone. This represents the shear force at the section located at the loading point x. This represents the reference value of the shear force within the stress zone, that is, the maximum value of the shear force across all sections within the stress zone. This represents the torque at the cross section located at the loading point x. This represents a reference value for the torque within a stress zone, that is, the maximum torque across all sections within that stress zone. This indicates the coordinates of the starting boundary of the stress-bearing zone. Indicates the coordinates of the termination boundary of the force-bearing zone. This represents the design variable, i.e., the location of the loading point.

[0040] Step 105: Apply loads to the optimal positions of each loading point to obtain the allocation factor matrix of the area of ​​interest. Combine the simulation results corresponding to the area of ​​interest to construct a load optimization model and solve for the optimal load at each loading point. In this embodiment, the optimal positions of all loading points are calibrated in the finite element model of the test object. After applying unit loads to each loading point in sequence, the response data of the area of ​​interest is extracted to obtain the corresponding allocation factor matrix. The strain data of the area of ​​interest, as well as the total load and total moment of the test object, are extracted from the simulation results. The loads at each loading point are used as design variables. Based on the allocation factor matrix, the loads and strain data at each loading point, the objective function is determined. The range of the load loading device, the conservation of the total load of the test object, and the conservation of the total moment are used as constraints to construct a load optimization model. The load optimization model is solved to obtain the optimal load corresponding to each loading point.

[0041] Specifically, using the optimal positions of each loading point obtained in step 104 as a benchmark, the allocation factor corresponding to each loading point is obtained through unit load response testing. Then, combined with the strain data of the preset areas of interest and simulation results, a load optimization model is built. The optimal load corresponding to all loading points is obtained through iterative solution. Among them, the allocation factor is used to characterize the contribution of the unit load of a single loading point to the strain of the areas of interest in the structure. The strain data is the standard strain response of the test object obtained by simulation under standard working conditions. The load optimization model is a numerical optimization solution model with load as the design variable and multiple constraints.

[0042] Furthermore, the optimal positions of all loading points are first calibrated in the finite element model of the test object. A unit load is applied sequentially to each calibrated loading point. Only a single loading point is applied at a time, while the other loading points are left unloaded. The mechanical response data of all parts of interest on the finite element model of the test object are collected simultaneously. The allocation factors corresponding to each loading point are then summarized and integrated to form an allocation factor matrix.

[0043] Subsequently, based on the experimental requirements and structural stress characteristics, multiple areas of interest were marked on the surface of the finite element model of the test object and at key structural locations. These areas of interest covered the main load-bearing structure, stress concentration areas, and key experimental points. In this application, the areas of interest can be any location other than the main force transmission path, such as stress concentration areas, connection areas, or fatigue-critical locations. The simulation results obtained in step 101 were retrieved, and strain data for each area of ​​interest, along with the total load and total moment of the test object, were extracted. The strain data from multiple areas of interest were then used to construct a strain data matrix.

[0044] Then, the loads at each loading point are set as design variables in the load optimization model, and multiple constraints are configured, including loading device range constraints, total load conservation constraints, and total moment conservation constraints. Among them, the loading device range constraints are used to limit the load at a single loading point from exceeding the safe operating range of the equipment, while the total load conservation and total moment conservation are used to ensure that the overall multi-point loading is equivalent to the force under actual working conditions.

[0045] The objective function of the load optimization model is constructed based on the allocation factor matrix, the load vector formed by the loads at each loading point, and the strain data matrix of the area of ​​interest. The objective function is based on minimizing the norm of the difference between the product of the allocation factor matrix and the load vector and the strain data matrix. After configuring all design variables, constraints, and the objective function, the load optimization model is completed. The load optimization model is iteratively solved using a numerical optimization algorithm, continuously correcting the load values ​​at each loading point. Under the premise of satisfying all constraints, optimal convergence of strain deviation is achieved, and finally, the optimal load corresponding to each loading point is obtained, completing the quantification and optimization configuration of the load for the full-scale static test.

[0046] For example, the objective function of the load optimization model is as follows: , The constraints are: , In the formula, This represents the sum of squared residuals, used to measure the deviation between the experimentally applied strain and the strain data in the simulation results. Represents the allocation factor matrix, This represents the load vector formed by the loads at each loading point. This represents the strain data matrix composed of strain data from various regions of interest in the simulation results. The norm square of a vector, i.e., the sum of the squares of all its elements, is used to quantify the overall deviation between the predicted strain data and the strain data in the simulation results. This indicates the minimum safe load of the loading device, i.e., the lowest load that can be applied to a single loading point, which is determined by the equipment capacity and test safety. This represents the load at the j-th loading point. This indicates the maximum safe load of the loading device, that is, the maximum load that can be applied to a single loading point, which is determined by the rated capacity of the equipment. This represents the total load in the simulation results, where m represents the total number of loading points. This represents the torque generated at the j-th loading point. This represents the total torque in the simulation results.

[0047] This application's embodiments employ a partitioning strategy guided by the main force transmission path to ensure a high degree of matching between the applied force and the actual stress state of the structure. By leveraging the collaborative solution of the position optimization model and the load optimization model, the loading accuracy and efficiency are effectively improved, while simultaneously meeting the actual constraints of the loading device. Compared to traditional empirical loading schemes, this application's method significantly reduces experimental errors and enhances the reliability and accuracy of experimental results, providing strong technical support for the efficient conduct of full-aircraft static tests. Furthermore, the partitioning boundary adjustment mechanism and load optimization constraint design of this method further enhance the flexibility and adaptability of the scheme, making it widely applicable to full-aircraft static test scenarios of different models and structural complexities, and possessing strong engineering practical value.

[0048] While this application provides the method operation steps as described in the embodiments or flowcharts, more or fewer operation steps may be included based on conventional or non-inventive labor. The order of steps listed in this embodiment is merely one possible execution order among many and does not represent the only execution order. In actual device or client product execution, the methods shown in this embodiment or the accompanying drawings can be executed sequentially or in parallel (e.g., in a parallel processor or multi-threaded processing environment).

[0049] like Figure 2 As shown in the figure, this application embodiment also provides a full-machine static test loading device 200 based on force transmission path. The device includes: a simulation module 201, an identification module 202, a partitioning module 203, a position solving module 204, and a load solving module 205, as detailed below.

[0050] The simulation module 201 is used to apply aerodynamic loads to the finite element model of the test object, perform static simulation, and obtain simulation results.

[0051] The identification module 202 is used to extract the main force transmission path and the internal force values ​​of each section on the main force transmission path based on the simulation results.

[0052] The partitioning module 203 is used to divide the main force transmission path into multiple force partitions based on the distribution characteristics of the internal force values ​​of each section.

[0053] The location solution module 204 is used to construct a location optimization model with the location of the loading point within the stress zone as the design variable and the zone boundary as the constraint, in order to solve for the optimal location of the loading point within each stress zone.

[0054] The load solving module 205 is used to apply loads to the optimal positions of each loading point to obtain the allocation factor matrix of the part of interest, and to construct a load optimization model by combining the simulation results corresponding to the part of interest, and to solve for the optimal load of each loading point.

[0055] Some modules in the apparatus described in this application can be described in the general context of computer-executable instructions that are executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, classes, etc., that perform a specific task or implement a specific abstract data type. This application can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside in local and remote computer storage media, including storage devices.

[0056] The apparatus or module described in the above embodiments can be implemented by a computer chip or physical entity, or by a product with a certain function. For ease of description, the above apparatus is described by dividing it into various modules according to their functions. When implementing the embodiments of this application, the functions of each module can be implemented in one or more software and / or hardware. Of course, a module that implements a certain function can also be implemented by combining multiple sub-modules or sub-units.

[0057] The methods, apparatus, or modules described in this application can be implemented in a computer-readable program code manner. The controller can be implemented in any suitable manner, such as a microprocessor or processor and a computer-readable medium storing computer-readable program code (e.g., software or firmware) executable by the (micro)processor, logic gates, switches, application-specific integrated circuits (ASICs), programmable logic controllers, and embedded microcontrollers. Examples of controllers include, but are not limited to, the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20, and Silicon Labs C8051F320. A memory controller can also be implemented as part of the control logic of a memory. Those skilled in the art will also recognize that, in addition to implementing the controller in purely computer-readable program code manner, the same functionality can be achieved by logically programming the method steps to make the controller take the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, such a controller can be considered a hardware component, and the means included within it for implementing various functions can also be considered as structures within the hardware component. Alternatively, the device used to implement various functions can be viewed as either a software module that implements the method or a structure within a hardware component.

[0058] This application also provides an apparatus, the apparatus comprising: a processor; a memory for storing processor-executable instructions; wherein, when the processor executes the executable instructions, it implements the method described in this application.

[0059] This application also provides a non-volatile computer-readable storage medium storing a computer program or instructions thereon, which, when executed, enables the method described in this application embodiment to be implemented.

[0060] Furthermore, in the various embodiments of this application, each functional module can be integrated into one processing module, or each module can exist independently, or two or more modules can be integrated into one module.

[0061] The aforementioned storage media include, but are not limited to, Random Access Memory (RAM), Read-Only Memory (ROM), Cache, Hard Disk Drive (HDD), or Memory Card. The memory can be used to store computer program instructions.

[0062] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary hardware. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product, or it can be embodied in the process of data migration. The computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, mobile terminal, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0063] The various embodiments described in this specification are presented in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on its differences from other embodiments. All or part of this application can be used in numerous general-purpose or special-purpose computer system environments or configurations. Examples include: personal computers, server computers, handheld or portable devices, tablet devices, mobile communication terminals, multiprocessor systems, microprocessor-based systems, programmable electronic devices, network PCs, minicomputers, mainframe computers, and distributed computing environments including any of the above systems or devices, etc.

[0064] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of this application.

Claims

1. A method for static load testing of an entire machine based on force transmission path, characterized in that, include: Aerodynamic loads were applied to the finite element model of the test object, and static simulation was performed to obtain the simulation results. Based on the simulation results, the main force transmission path and the internal force values ​​of each section on the main force transmission path are extracted. Based on the distribution characteristics of the internal force values ​​at each cross section, the main force transmission path is divided into multiple force zones, including: constructing corresponding internal force vectors based on the internal force values ​​at each cross section; determining the vector angle between the internal force vectors of two adjacent cross sections, and determining the zone boundary according to the variation characteristics of the vector angle; dividing the main force transmission path into multiple continuous force zones according to the zone boundary; wherein, the internal force vector is a characteristic vector formed by the combination of bending moment, shear force, and torque values ​​of a single cross section; Using the positions of the loading points within the stress zones as design variables and the zone boundaries as constraints, a position optimization model is constructed to solve for the optimal positions of the loading points within each stress zone. This includes: using the positions of the loading points to be deployed within each stress zone as design variables, using the two side boundaries of the current stress zone as position constraints, using the comprehensive internal force index of the cross section as the objective function, and taking the minimum of the comprehensive internal force index of the cross section as the optimization objective, iteratively solving the position optimization model until the comprehensive internal force index of the cross section reaches its minimum and the results converge, thus obtaining the optimal position within the stress zone, which is the position of the corresponding loading point; wherein, the comprehensive internal force index of the cross section is calculated from the Euclidean norm of the bending moment, shear force, and torque of the cross section. Loads are applied to the optimal positions of each loading point to obtain the allocation factor matrix of the part of interest. The load optimization model is constructed by combining the simulation results corresponding to the part of interest and the optimal load of each loading point is obtained by solving the model.

2. The method according to claim 1, characterized in that, The simulation results include stress data, strain data, internal force values, and the total load and total torque of the test object.

3. The method according to claim 2, characterized in that, The extraction of the main force transmission path and the internal force values ​​of each section along the main force transmission path based on the simulation results includes: A stress cloud map is generated based on the stress data in the simulation results, and the main force transmission path is extracted from the stress cloud map. Multiple sections are cut along the main force transmission path at a preset cross-sectional distance, and the internal force values ​​of each section are extracted; wherein, the internal force values ​​include bending moment, shear force and torque.

4. The method according to claim 1, characterized in that, The step of determining the partition boundary based on the variation characteristics of the vector angle includes: The location where the angle between the vectors changes abruptly is determined as the partition boundary.

5. The method according to claim 1, characterized in that, The step of determining the partition boundary based on the variation characteristics of the vector angle further includes: When the number of partition boundaries meets a preset range, the partition boundaries are retained; When the number of partition boundaries is greater than the upper limit of the preset number range, multiple partition boundaries are selected according to the included angle of the vectors so that the number of partition boundaries meets the preset number range. When the number of partition boundaries is less than the lower limit of the preset number range, the main force transmission path is divided into equal segments, and the number of segments satisfies the preset number range, thus generating new partition boundaries.

6. The method according to claim 2, characterized in that, The process involves applying loads to the optimal positions of each loading point to obtain the allocation factor matrix for the region of interest, constructing a load optimization model based on the simulation results corresponding to the region of interest, and solving for the optimal load at each loading point, including: In the finite element model of the test object, the optimal positions of all loading points are calibrated. After applying unit loads to each loading point in sequence, the response data of the parts of interest are extracted to obtain the corresponding allocation factor matrix. Extract strain data of the area of ​​interest, as well as the total load and total moment of the test object, from the simulation results; Using the load at each loading point as the design variable, the objective function is determined based on the allocation factor matrix, the load at each loading point, and the strain data. The load optimization model is constructed with the range of the load loading device, the total load conservation of the test object, and the total torque conservation as constraints. Solve the load optimization model to obtain the optimal load for each loading point.

7. A static load-bearing device for a whole machine based on a force transmission path for implementing the method described in any one of claims 1-6, characterized in that, include: The simulation module is used to apply aerodynamic loads to the finite element model of the test object, perform static simulation, and obtain simulation results. The identification module is used to extract the main force transmission path and the internal force values ​​of each section on the main force transmission path based on the simulation results. The partitioning module is used to divide the main force transmission path into multiple force partitions based on the distribution characteristics of the internal force values ​​of each cross section. This includes: constructing corresponding internal force vectors based on the internal force values ​​of each cross section; determining the vector angle between the internal force vectors of two adjacent cross sections; determining the partition boundary based on the variation characteristics of the vector angle; and dividing the main force transmission path into multiple continuous force partitions based on the partition boundary. The internal force vector is a characteristic vector formed by the combination of bending moment, shear force, and torque values ​​of a single cross section. The location solving module is used to construct a location optimization model with the location of the loading point within the stress zone as the design variable and the zone boundary as the constraint, in order to solve for the optimal location of the loading point within each stress zone. This includes: using the location of the loading point to be deployed within each stress zone as the design variable, the two side boundaries of the current stress zone as the location constraint, using the cross-sectional comprehensive internal force index as the objective function, and taking the minimum cross-sectional comprehensive internal force index as the optimization objective, iteratively solving the location optimization model until the cross-sectional comprehensive internal force index reaches its minimum and the result converges, thus obtaining the optimal location within the stress zone, which is the location of the corresponding loading point; wherein, the cross-sectional comprehensive internal force index is calculated from the Euclidean norm of the bending moment, shear force, and torque of the cross section; The load solving module is used to apply loads to the optimal positions of each loading point to obtain the allocation factor matrix of the part of interest, and to construct a load optimization model by combining the simulation results corresponding to the part of interest, and to solve for the optimal load of each loading point.

8. An apparatus for performing a full-machine static load test method based on a force transmission path, characterized in that, include: processor; Memory used to store processor-executable instructions; When the processor executes the executable instructions, it implements the method as described in any one of claims 1 to 6.

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