Railway vehicle coupler collision load measuring method and system

Abstract

The invention relates to the technical field of collision measurement, and discloses a railway vehicle coupler collision load measurement method and system, and the method comprises the steps: constructing a coupler collision finite element simulation model, and determining a segmentation step length and an error correction tolerance; acquiring a coupler load characteristic curve of the coupler collision system, and calculating a displacement response of the coupler collision system based on the coupler load characteristic curve and the finite element simulation model; determining the calculated displacement of the feature point in the coupler collision system through the displacement response, determining the observed displacement of the feature point based on the collision test of the coupler collision system, and calculating an error value based on the calculated displacement and the observed displacement; comparing the error value with the error correction error tolerance, and correcting the finite element simulation model based on a comparison result to obtain a corrected finite element simulation model; calculating a load characteristic curve in the car coupler collision process by utilizing the corrected finite element simulation model; the problem that an existing hook collision load measuring method is low in precision is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of collision measurement, and in particular to a method and system for measuring collision load of a rail vehicle coupler. Background Art

[0002] When a train collides, it is easy to cause various instability forms such as derailment and climbing. As the core force transmission component connecting the car body, the load transfer characteristics of the coupler during collision play an important role in maintaining the collision posture of the adjacent car body. When conducting coupler collision test research, in the rigid wall collision scenario, only the longitudinal collision load can be measured by the force sensor, while the lateral and vertical loads cannot be directly obtained; for the line collision scenario, the longitudinal collision load of the coupler cannot be directly measured.

[0003] Coupler collision is a typical time-series load action process with a short action time (usually ≤1s), and the existing coupler load inverse measurement technology is difficult to apply directly. For example, "Combined electric bridge type coupler multi-element multi-directional load measurement system and decoupling method" (CN201911053546.2) and "Couplet force measurement method and system considering longitudinal loading additional bending moment" (CN202111671409.2) collect the strain distribution and change law of the coupler when it is stressed, and solve the inverse coupler load. However, for coupler collision scenarios, the short-term high-precision measurement of strain data is very demanding. At the same time, structural damage to the coupler will cause a certain degree of damage to the strain measurement points and lines, thereby affecting the accuracy of the strain data and inverse load.

[0004] Unlike strain testing, which is difficult to implement, it is more reliable and accurate to shoot the video of the coupler action with a high-speed camera, record and measure the posture changes of the coupler and the displacement curve of the key feature points during the collision test. Therefore, it is a feasible solution to inversely calculate the load through the displacement response. The mapping relationship between the coupler load and the characteristic point displacement can be obtained by establishing and solving the corresponding finite element simulation model, that is, by adjusting the load input in the coupler collision simulation model, the calculated characteristic point displacement gradually approaches the measured response. When the approximation error meets the preset accuracy requirements, it can be considered that the model load input at this time is an approximation of the real load of the coupler.

[0005] On the other hand, the inverse of the coupler collision load curve usually causes an error accumulation effect, that is, the inverse curve gradually deviates from the target curve over time. In view of this, the present invention proposes a coupler collision load inverse method based on "segmented progressive, backtracking error correction", which divides the complete coupler collision process into segments, performs load inverse segment by segment, and judges according to the preset deviation error tolerance in the process. If the error is too large, it will be backtracked to the maximum deviation moment for the next round of inverse. Through multiple iterations, the recognition accuracy of the coupler collision load can be better improved. Summary of the invention

[0006] The invention provides a rail vehicle coupler collision load measurement method and system to solve the problem of low precision in the existing hook collision load measurement method.

[0007] In order to achieve the above object, the present invention is implemented by the following technical solutions: In a first aspect, the present invention provides a method for measuring a collision load of a rail vehicle coupler, comprising: According to the coupler collision test, a coupler collision finite element simulation model is constructed, and the segmentation step size and error correction tolerance are determined; Acquire a coupler load characteristic curve of the coupler collision system based on theoretical experience and previous experiments, and calculate a displacement response corresponding to each segmented step of the coupler collision system based on the coupler load characteristic curve and the finite element simulation model; Determine the calculated displacement of the characteristic point in each segmented step by the displacement response, determine the observed displacement of the characteristic point in each segmented step based on a collision test of the coupler collision system, and calculate the error value in each segmented step based on the calculated displacement and the observed displacement in each segmented step; The error value in each segmented step is compared with the error correction tolerance, and when the error value is greater than the error correction tolerance, the error value in the segmented step is iteratively calculated, and the finite element simulation model is corrected based on the iterative result; When the error values ​​in all segmented step sizes are less than or equal to the error correction tolerance, a final corrected finite element simulation model is obtained, and the collision load during the coupler collision process is calculated using the final corrected finite element simulation model.

[0008] Optionally, the segmented step length is a segment of the total duration during the coupler collision test, and the segmentation requirements are: The total duration of the coupler collision test is divided into N equal parts, where N is a positive integer greater than 2, each part after the N equal parts is a segmented step, and the sum of the N segmented step lengths is the total duration of the coupler collision test.

[0009] Optionally, the calculating the displacement response corresponding to each segmented step of the coupler collision system based on the coupler load characteristic curve and the finite element simulation model includes: The coupler load characteristic curve is used as the initial input to calculate the displacement response of the coupler collision system, and the calculation satisfies the following relationship: ; Where M represents the mass characteristic of the coupler collision system, C and K represent the damping and stiffness characteristics respectively, and F represents the external load characteristics. , as well as They represent the acceleration, velocity and displacement responses of the coupler collision system respectively.

[0010] Optionally, the calculating the error value in each segmented step based on the calculated displacement and the observed displacement in each segmented step includes: ; In the formula, Represents the error value, which is the sum of the displacement errors of each feature point. , Respectively i The calculated displacement and observed displacement of each feature point.

[0011] Optionally, when the error value is greater than the error correction error tolerance, iteratively calculating the error value in the segmented step size includes: When the error value in the current segmented step is greater than the error correction tolerance, the damping characteristics and stiffness characteristics in the finite element simulation model are updated, and the displacement response corresponding to the segmented step is recalculated using the updated finite element simulation model, and then the new error value is calculated using the new displacement response until the error value in the segmented step is less than or equal to the error correction tolerance.

[0012] Optionally, the iterative calculation further includes: When the damping characteristics and stiffness characteristics in the finite element simulation model can no longer be updated during iterative calculation of a certain segmented step, it is determined that the current iteration has reached the maximum number of iterations; When the iterative calculation reaches the maximum number of iterations, all error values ​​in the iterative calculation are obtained for comparison to obtain the maximum error value, and the time when the maximum error value appears is used as the starting point for the next round of iterative calculation.

[0013] Optionally, the correcting the finite element simulation model based on the iteration result includes: All segmented step lengths are sorted in chronological order, and the damping characteristics and stiffness characteristics in the finite element simulation model are updated through iterative calculation in the sorted order, and the updated finite element simulation model is a corrected finite element simulation model; After the segmented step size of the current moment has corrected the finite element simulation model in the iterative calculation, the segmented step size of the adjacent next moment adopts the finite element simulation model corrected by the iterative calculation of the previous moment when performing calculation.

[0014] Optionally, when the error values ​​in all segmented step sizes are less than or equal to the error correction error tolerance, the final corrected finite element simulation model is obtained, comprising: When the error values ​​in all segmented steps are less than or equal to the error correction tolerance after iterative calculation, the finite element simulation model corrected by the last segmented step iterative calculation is the final corrected finite element simulation model.

[0015] Optionally, the calculating the collision load during the coupler collision process using the finally corrected finite element simulation model includes: The collision load during the coupler collision process is calculated using the final corrected finite element simulation model to obtain the final collision load, which satisfies the following relationship: ; Where M represents the mass characteristic of the coupler collision system, C d , K t They represent the damping and stiffness characteristics after correction and update, and F represents the external load characteristics. , as well as They represent the acceleration, velocity and displacement responses of the coupler collision system respectively.

[0016] In a second aspect, an embodiment of the present application provides a rail vehicle coupler collision load measurement system, including a processor and a memory; Memory, used to store computer programs; The processor is used to implement any method step described in the first aspect when executing a program stored in the memory.

[0017] Beneficial effects: The rail vehicle coupler collision load measurement method provided by the present invention constructs a coupler collision finite element simulation model according to a coupler collision test, and determines the segmented step size and the error correction tolerance; obtains the coupler load characteristic curve of the coupler collision system based on theoretical experience and previous experiments, and calculates the displacement response of the coupler collision system based on the coupler load characteristic curve and the finite element simulation model; determines the calculated displacement of the characteristic point in the coupler collision system through the displacement response, determines the observed displacement of the characteristic point based on the collision test of the coupler collision system, and calculates the error value based on the calculated displacement and the observed displacement; compares the error value with the error correction tolerance, and corrects the finite element simulation model based on the comparison result to obtain the corrected finite element simulation model; and uses the corrected finite element simulation model to calculate the load characteristic curve during the coupler collision process. The present invention uses load inversion based on displacement response approximation, which is easier to obtain than strain measurement and has higher reliability, and is particularly suitable for coupler collision scenarios.

[0018] It is further worth mentioning that this method adopts a piecewise progressive inverse identification framework, which discretizes the entire collision process into multiple stages. In each stage, the inverse is only for one segment, so as to gradually update the model load input curve, improve the accuracy of load identification, and introduce a backtracking error correction mechanism, which can effectively control the error accumulation in the progressive iteration process and ensure that the errors of the entire load identification process are within the tolerance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A flow chart of a method for measuring a rail vehicle coupler collision load according to a preferred embodiment of the present invention; Figure 2 This is a schematic diagram of a test scenario of a single vehicle coupler impacting a rigid wall according to a preferred embodiment 1 of the present invention; Figure 3 This is a comparison diagram of the results of a single hook hitting a rigid wall scenario in the preferred embodiment 1 of the present invention; Figure 4 This is a schematic diagram of a coupler offset collision test scenario of a preferred embodiment 2 of the present invention; Figure 5 This is a comparison diagram of the longitudinal displacement curves of the offset collision of the coupler of the preferred embodiment 2 of the present invention; Figure 6 This is a comparison diagram of vertical displacement of the offset collision of the coupler of the preferred embodiment 2 of the present invention; Figure 7 This is a comparison diagram of the lateral displacement of the offset collision of the coupler of the preferred embodiment 2 of the present invention; Figure 8 This is a schematic diagram of the load identification of the coupler offset collision according to the preferred embodiment 2 of the present invention; Fig. 9 This is a schematic diagram of a scenario of a simulated track collision test of a coupler according to a preferred embodiment 3 of the present invention; Fig.10 A comparison diagram of displacement curves of simulated line collision of a coupler in preferred embodiment 3 of the present invention; Fig.11 It is a load diagram for identifying a coupler simulation line collision test according to a preferred embodiment 3 of the present invention; Fig.12 A logic block diagram of iterative calculation of a preferred embodiment of the present invention; In the figure, 1.1, the first rigid wall; 1.2, the first force sensor; 1.3, the first high-speed camera; 1.4, the first test trolley; 1.5, the first track; 1.6, the first hook to be impacted; 1.7, the second high-speed camera; 1.8, the first fixed hook head; 2.1, the second rigid wall; 2.2, the second force sensor; 2.3, the third high-speed camera; 2.4, the second test trolley; 2.5, the second track; 2.6, the moving hook; 2.7, the fourth high-speed camera; 2.8, the stationary hook; 3.1, the third rigid wall; 3.2, the front trolley; 3.3, the hook to be tested; 3.4, the rear trolley; 3.5, the third track; 3.6, the fifth high-speed camera. DETAILED DESCRIPTION

[0020] The technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the usual meanings understood by persons with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not indicate quantity restrictions, but indicate the existence of at least one. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship also changes accordingly.

[0022] Example 1 See also Figure 1 The present application provides a method for measuring a collision load of a rail vehicle coupler, comprising: According to the coupler collision test, a coupler collision finite element simulation model is constructed, and the segmentation step size and error correction tolerance are determined; The coupler load characteristic curve of the coupler collision system is obtained based on theoretical experience and previous experiments, and the displacement response corresponding to each segmented step of the coupler collision system is calculated based on the coupler load characteristic curve and the finite element simulation model; Determine the calculated displacement of the characteristic point in each segmented step by the displacement response, determine the observed displacement of the characteristic point in each segmented step based on the collision test of the coupler collision system, and calculate the error value in each segmented step based on the calculated displacement and the observed displacement in each segmented step; The error value in each segmented step is compared with the error correction tolerance, and when the error value is greater than the error correction tolerance, the error value in the segmented step is iteratively calculated, and the finite element simulation model is corrected based on the iterative result; When the error values ​​in all segmented step sizes are less than or equal to the error correction tolerance, a final corrected finite element simulation model is obtained, and the collision load during the coupler collision process is calculated using the final corrected finite element simulation model.

[0023] Optionally, the segmented step length is a segment of the total duration during the coupler collision test, and the segmentation requirements are: The total duration of the coupler collision test is divided into N equal parts, where N is a positive integer greater than 2, each part after the N equal parts is a segmented step, and the sum of the N segmented step lengths is the total duration of the coupler collision test.

[0024] Optionally, the calculating the displacement response corresponding to each segmented step of the coupler collision system based on the coupler load characteristic curve and the finite element simulation model includes: The coupler load characteristic curve is used as the initial input to calculate the displacement response of the coupler collision system, and the calculation satisfies the following relationship: ; Where M represents the mass characteristic of the coupler collision system, C and K represent the damping and stiffness characteristics respectively, and F represents the external load characteristics. , as well as They represent the acceleration, velocity and displacement responses of the coupler collision system respectively.

[0025] Optionally, the calculating the error value in each segmented step based on the calculated displacement and the observed displacement in each segmented step includes: ; In the formula, Represents the error value, which is the sum of the displacement errors of each feature point. , Respectively i The calculated displacement and observed displacement of each feature point.

[0026] Optionally, when the error value is greater than the error correction error tolerance, iteratively calculating the error value in the segmented step size includes: When the error value in the current segmented step is greater than the error correction tolerance, the damping characteristics and stiffness characteristics in the finite element simulation model are updated, and the displacement response corresponding to the segmented step is recalculated using the updated finite element simulation model, and then the new error value is calculated using the new displacement response until the error value in the segmented step is less than or equal to the error correction tolerance.

[0027] Optionally, the iterative calculation further includes: When the damping characteristics and stiffness characteristics in the finite element simulation model can no longer be updated during iterative calculation of a certain segmented step, it is determined that the current iteration has reached the maximum number of iterations; When the iterative calculation reaches the maximum number of iterations, all error values ​​in the iterative calculation are obtained for comparison to obtain the maximum error value, and the time when the maximum error value appears is used as the starting point for the next round of iterative calculation.

[0028] Optionally, the correcting the finite element simulation model based on the iteration result includes: All segmented step lengths are sorted in chronological order, and the damping characteristics and stiffness characteristics in the finite element simulation model are updated through iterative calculation in the sorted order, and the updated finite element simulation model is a corrected finite element simulation model; After the segmented step size of the current moment has corrected the finite element simulation model in the iterative calculation, the segmented step size of the adjacent next moment adopts the finite element simulation model corrected by the iterative calculation of the previous moment when performing calculation.

[0029] Optionally, when the error values ​​in all segmented step sizes are less than or equal to the error correction error tolerance, the final corrected finite element simulation model is obtained, comprising: When the error values ​​in all segmented steps are less than or equal to the error correction tolerance after iterative calculation, the finite element simulation model corrected by the last segmented step iterative calculation is the final corrected finite element simulation model.

[0030] In the above embodiment, the iterative calculation process is as follows: Fig.12 As shown in the figure, the iterative calculation follows the idea of ​​gradual backtracking. Each time, only a small section is simulated, a small section is corrected, and then a small section is simulated again, and then a small section is corrected again, and this process is repeated until the entire time domain is traversed. This is the embodiment of the gradual idea. Here, a small section refers to the step length of each segment. Each segment has an error judgment. If the errors at all moments in this segment meet the error tolerance, the iteration of the next segment starts from the current last moment. If this small segment is iterated many times (reaching the pre-defined maximum number of times) and still cannot ensure that the error requirements are met at every moment, then the next small segment will be calculated from the place with the largest error in this segment, which is equivalent to recalculating the part of this segment that exceeds the error. This is the embodiment of the idea of ​​backtracking.

[0031] Optionally, the calculating the collision load during the coupler collision process using the finally corrected finite element simulation model includes: The collision load during the coupler collision process is calculated using the final corrected finite element simulation model to obtain the final collision load, which satisfies the following relationship: ; Where M represents the mass characteristic of the coupler collision system, C d , K t They represent the damping and stiffness characteristics after correction and update, and F represents the external load characteristics. , as well as They represent the acceleration, velocity and displacement responses of the coupler collision system respectively.

[0032] In this embodiment, a verification example is a scenario where a single hook hits a rigid wall.

[0033] like Figure 2 The figure shows a schematic diagram of a single hook impacting a rigid wall test scenario, wherein a first force sensor 1.2 and a first fixed hook head 1.8 are installed at the front end of the first rigid wall 1.1, the first fixed hook head 1.8 is used to match the first hook 1.6 to be impacted, the first hook 1.6 to be impacted is installed at the front end of the first test trolley 1.4 and maintained at the same height as the first fixed hook head 1.8. During the test, the first test trolley 1.4 moves along the first track 1.5 at a specified speed to impact the first rigid wall 1.1, the first high-speed camera 1.3 arranged above the impact area and the second high-speed camera 1.7 on the side will respectively shoot the top-down and main-perspective videos of the hook impact process, and record the displacement-time curve of the hook during the process; the force sensor at the rigid wall end records the longitudinal collision load during the impact process.

[0034] In this scenario, the installation height of the coupler and the fixed hook head is consistent, so only crushing deformation displacement along the track direction (longitudinal) will occur during the impact, thereby generating a longitudinal load. Therefore, the collision load obtained by the force sensor is the actual load on the coupler, and can be used as a reference to verify the accuracy of the collision load identified by inverse analysis of the solution of the present invention.

[0035] The specific process of coupler collision load identification in this example is as follows: ① Parameter pre-definition: the entire impact process lasts 175ms, the segment step length S is set to 40ms, and the error correction tolerance is It is set to 5%; the simulated annealing algorithm is used in each stage of iterative inversion, and the maximum number of iterations is set to 100.

[0036] ② Phased reverse iteration: A single coupler collision simulation model consistent with the test scenario is established, and reverse iterations are performed one by one according to the set segment step size. Finally, after 12 rounds of iterations, the entire collision process is traversed and the iterative reverse iteration is completed.

[0037] ③ Collision load output: Output the load characteristic curve during the coupler collision process, that is, the coupler collision load obtained by reverse identification, and compare it with the test data of the force sensor to calculate the error; output the calculated coupler displacement-time curve, and compare it with the displacement-time curve recorded by the high-speed camera to calculate the error. The final results are as follows: Figure 3 And as shown in Table 1.

[0038] Table 1 Load identification error of a single coupler hitting a rigid wall

[0039] The results show that the load identification method proposed in this invention can accurately identify the coupler collision load, which illustrates the effectiveness of this scheme.

[0040] Example 2 In this embodiment, an extended example is a coupling offset collision scenario.

[0041] like Figure 4 The figure shows a schematic diagram of a coupler offset collision test scenario, wherein a second force sensor 2.2 and a stationary coupler 2.8 are installed at the front end of the second rigid wall 2.1. The stationary coupler 2.8 is used to match the moving coupler 2.6. The moving coupler 2.6 is installed at the front end of the second test trolley 2.4, and the installation height is 40 mm higher than that of the stationary coupler. During the test, the second test trolley 2.4 moves along the second track 2.5 at a specified speed to collide with the second rigid wall 2.1. The third high-speed camera 2.3 arranged above the collision area and the fourth high-speed camera 2.7 on the side will respectively shoot the bird's-eye view and main perspective video of the coupler collision process, and record the displacement-time curves of the two couplers in the process; the force sensor at the rigid wall end records the longitudinal collision load during the collision.

[0042] In this scenario, the installation heights of the moving and stationary couplers are not consistent. Therefore, during the collision, as the two coupler heads fit together, longitudinal, lateral, and vertical movement displacements will occur, thereby generating collision loads in three directions. Therefore, the collision load obtained by the force sensor is only the longitudinal load generated by the coupler, and can be used as a partial reference to verify the accuracy of the collision load identified by reverse analysis of the present invention.

[0043] The specific process of coupler collision load identification in this example is as follows: ① Parameter pre-definition: the entire impact process lasts 130ms, the segment step length S is set to 30ms, and the error correction tolerance is It is set to 5%; the simulated annealing algorithm is used in each stage of iterative inversion, and the maximum number of iterations is set to 100.

[0044] ② Phased inverse iteration: Establish a coupler collision simulation model consistent with the test scenario, and perform inverse iterations one by one according to the set segment step size. Finally, after 9 rounds of iterations, the entire collision process is traversed and the iterative inverse is completed.

[0045] ③ Collision load output: Output the load characteristic curve during the coupler collision process, that is, the coupler collision load obtained by reverse identification, and compare it with the test data of the force sensor to calculate the error; output the calculated coupler displacement-time curve, and compare it with the displacement-time curve recorded by the high-speed camera to calculate the error. The final results are as follows: Figure 5-Figure 8 And as shown in Table 2.

[0046] Table 2 Load identification error of coupler offset collision scenario

[0047] Example 3 In this embodiment, the application example - the coupler simulates the line collision scenario.

[0048] like Fig. 9 The figure shows a schematic diagram of a simulated track collision test scenario for a coupler, wherein a protective energy-absorbing structure 3.7 is installed at the front end of the third rigid wall 3.1 to avoid a rigid collision between the front trolley 3.2 and the third rigid wall 3.1. The coupler 3.3 to be tested is installed between the front trolley 3.2 and the rear trolley 3.4. During the test, the two trolleys move together along the third track 3.5 at a specified speed and collide with the third rigid wall 3.1. The fifth high-speed camera 3.6 arranged on the side of the collision area will shoot a main-view video of the coupler collision process and record the displacement-time curves of the two trolleys during the process.

[0049] In this scenario, the location where the hook hits is not at the front end of the rigid wall, so the collision load generated during the collision cannot be measured directly and can only be obtained by inverse calculation using the method of the present invention.

[0050] The specific process of coupler collision load identification in this example is as follows: ① Parameter pre-definition: the entire impact process lasts 250ms, the segment step length S is set to 50ms, and the error correction tolerance is It is set to 5%; the simulated annealing algorithm is used in each stage of iterative inversion, and the maximum number of iterations is set to 100.

[0051] ② Phased reverse iteration: Establish a coupler collision simulation model consistent with the test scenario, and perform reverse iterations one by one according to the set segment step size. Finally, after 5 rounds of iterations, the entire collision process is traversed and the iterative reverse iteration is completed.

[0052] ③ Collision load output: Output the load characteristic curve during the coupler collision process, which is the coupler collision load obtained by reverse identification. The final results are as follows: Figure 10-11 And as shown in Table 3.

[0053] Table 3 Coupler simulation line collision scenario error

[0054] The embodiment of the present application also provides a rail vehicle coupler collision load measurement system, including a processor and a memory; Memory, used to store computer programs; The processor is used to implement any method step of the method for measuring the collision load of a coupler of a rail vehicle when executing the program stored in the memory.

[0055] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A method for measuring collision load of a rail vehicle coupler, characterized in that: include: According to the coupler collision test, a coupler collision finite element simulation model is constructed, and the segmentation step size and error correction tolerance are determined; Acquire a coupler load characteristic curve of the coupler collision system based on theoretical experience and previous experiments, and calculate a displacement response corresponding to each segmented step of the coupler collision system based on the coupler load characteristic curve and the finite element simulation model; Determine the calculated displacement of the characteristic point in each segmented step by the displacement response, determine the observed displacement of the characteristic point in each segmented step based on a collision test of the coupler collision system, and calculate the error value in each segmented step based on the calculated displacement and the observed displacement in each segmented step; The error value in each segmented step is compared with the error correction tolerance, and when the error value is greater than the error correction tolerance, the error value in the segmented step is iteratively calculated, and the finite element simulation model is corrected based on the iterative result; When the error values ​​in all segmented step sizes are less than or equal to the error correction tolerance, a final corrected finite element simulation model is obtained, and the collision load during the coupler collision process is calculated using the final corrected finite element simulation model.

2. The method for measuring the collision load of a rail vehicle coupler according to claim 1, characterized in that: The segmented step length is a section of the total duration during the coupler collision test, and its division requirements are: The total duration of the coupler collision test is divided into N equal parts, where N is a positive integer greater than 2, each segment after the N equal parts is a segment step, and the sum of the N segment step lengths is the total duration of the coupler collision test.

3. The method for measuring the collision load of a rail vehicle coupler according to claim 1, characterized in that: The calculating the displacement response corresponding to each segmented step of the coupler collision system based on the coupler load characteristic curve and the finite element simulation model includes: The coupler load characteristic curve is used as the initial input to calculate the displacement response of the coupler collision system, and the calculation satisfies the following relationship: ； Where M represents the mass characteristic of the coupler collision system, C and K represent the damping and stiffness characteristics respectively, and F represents the external load characteristics. , as well as They represent the acceleration, velocity and displacement responses of the coupler collision system respectively.

4. The method for measuring the collision load of a rail vehicle coupler according to claim 1, characterized in that: The step of calculating the error value in each segmented step based on the calculated displacement and the observed displacement in each segmented step comprises: ； In the formula, Represents the error value, which is the sum of the displacement errors of each feature point. , Respectively i The calculated displacement and observed displacement of each feature point.

5. The method for measuring the collision load of a rail vehicle coupler according to claim 1, characterized in that: When the error value is greater than the error correction error tolerance, iteratively calculating the error value in the segmented step length comprises: When the error value in the current segmented step is greater than the error correction tolerance, the damping characteristics and stiffness characteristics in the finite element simulation model are updated, and the displacement response corresponding to the segmented step is recalculated using the updated finite element simulation model, and then the new error value is calculated using the new displacement response until the error value in the segmented step is less than or equal to the error correction tolerance.

6. The method for measuring the collision load of a rail vehicle coupler according to claim 5, characterized in that: The method further comprises: When the damping characteristics and stiffness characteristics in the finite element simulation model can no longer be updated during iterative calculation of a certain segmented step, it is determined that the current iteration has reached the maximum number of iterations; When the iterative calculation reaches the maximum number of iterations, all error values ​​in the iterative calculation are obtained for comparison to obtain the maximum error value, and the time when the maximum error value appears is used as the starting point for the next round of iterative calculation.

7. The method for measuring the collision load of a rail vehicle coupler according to claim 1, characterized in that: The method of correcting the finite element simulation model based on the iteration result includes: All segmented step lengths are sorted in chronological order, and the damping characteristics and stiffness characteristics in the finite element simulation model are updated through iterative calculation in the sorted order, and the updated finite element simulation model is a corrected finite element simulation model; After the segmented step size of the current moment has corrected the finite element simulation model in the iterative calculation, the segmented step size of the adjacent next moment adopts the finite element simulation model corrected by the iterative calculation of the previous moment when performing calculation.

8. The method for measuring the collision load of a rail vehicle coupler according to claim 1, characterized in that: The finite element simulation model after final correction is obtained when the error values ​​in all segmented step sizes are less than or equal to the correction error tolerance, including: When the error values ​​in all segmented steps are less than or equal to the error correction tolerance after iterative calculation, the finite element simulation model corrected by the last segmented step iterative calculation is the final corrected finite element simulation model.

9. The method for measuring the collision load of a rail vehicle coupler according to claim 1, characterized in that: The method of calculating the collision load during the coupler collision process using the final corrected finite element simulation model includes: The collision load during the coupler collision process is calculated using the final corrected finite element simulation model to obtain the final collision load, which satisfies the following relationship: ； Where M represents the mass characteristic of the coupler collision system, C d , K t They represent the damping and stiffness characteristics after correction and update, and F represents the external load characteristics. , as well as They represent the acceleration, velocity and displacement responses of the coupler collision system respectively.

10. A rail vehicle coupler collision load measurement system, characterized in that: Including processor and memory; Memory, used to store computer programs; A processor, for implementing the method steps described in any one of claims 1 to 9 when executing a program stored in a memory.

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