Method, device and equipment for analyzing service life of plate spring system

Abstract

The invention relates to the technical field of vehicle testing, and discloses a plate spring system life analysis method, device and equipment, and the method comprises the steps: obtaining the actual load time sequence data of a target vehicle containing a plate spring system in a test field; wherein the actual load time sequence data comprises load force time sequence data, vibration time sequence data and round trip time sequence data; performing hierarchical statistics on the basis of the load force time sequence data, the vibration time sequence data and the round trip time sequence data to obtain a hierarchical load under a preset working condition; applying the load force, the vibration acceleration and the wheel jump corresponding to any graded load to a pre-established finite element model to obtain simulation stress data of the finite element model; according to the simulation stress data and the graded load, whether the plate spring system meets the service life requirement or not is judged. The method has the beneficial effects that the actual load borne by the plate spring system is reflected by a plurality of load parameters, and the technical effect of improving the accuracy of the grading result of the service life of the plate spring system is achieved by carrying out grading statistics on the load parameters.

Description

Technical Field

[0001] The present application relates to the field of vehicle testing technology, and in particular to a leaf spring system life analysis method, device and equipment. Background Art

[0002] In the process of automobile design and manufacturing, the leaf spring system is a very important part. The leaf spring system is usually installed in the suspension part of the vehicle to absorb the vibration generated by the vehicle during driving and the impact of the road on the vehicle, thereby providing users with vehicle stability and driving comfort. The wear of the leaf spring system has a direct impact on the vehicle's load-bearing capacity, so whether the life of the leaf spring system meets the requirements is crucial. In the relevant technologies for life analysis of leaf spring systems, the degree of consistency between the data used and the actual situation and the accuracy of the analysis results need to be improved. Summary of the invention

[0003] The present application provides a leaf spring system life analysis method, device and equipment, which use multiple load parameters to reflect the actual load on the leaf spring system, and achieve the technical effect of improving the accuracy of the leaf spring system life classification results by classifying and statistically analyzing the load parameters.

[0004] In order to achieve the above objectives, the main technical solutions adopted in this application include:

[0005] In a first aspect, an embodiment of the present application provides a leaf spring system life analysis method, the method comprising:

[0006] Acquire actual load time series data of the target vehicle including the leaf spring system in the test field; wherein the actual load time series data includes load force time series data, vibration time series data and wheel hop time series data of the vehicle tire;

[0007] Based on the load force time series data, the vibration time series data and the wheel hop time series data, hierarchical statistics are performed to obtain a hierarchical load under a preset working condition; wherein the hierarchical load is used to characterize the load force level, vibration level and wheel hop level of the target vehicle under the preset working condition;

[0008] Apply the load force, vibration acceleration and wheel jump corresponding to any graded load to a pre-established finite element model to obtain simulation stress data of the finite element model under the any graded load;

[0009] According to the simulation stress data and the graded load, it is determined whether the leaf spring system meets the life requirement; wherein the life requirement is that the leaf spring system does not break when the target vehicle reaches a target mileage.

[0010] The leaf spring system life analysis method proposed in the embodiment of the present application obtains a graded load representing the leaf spring system by collecting multiple load parameters of the leaf spring system and performing graded statistics on the above load parameters, wherein the graded load represents the mode of the load actually borne by the leaf spring system. By performing statistics and classifying the loads, the complexity of the data is reduced and the accuracy of the life analysis results is improved. In addition, the graded load is a combination of multiple load parameters that reflect the actual load borne by the leaf spring system in the test field, which can be used to calculate the stress data generated by the leaf spring system under the load. Compared with the direct collection of stress data in the related art, the obtained result is more consistent with the actual load borne by the leaf spring system, and the degree of consistency between the analysis result and the actual situation is improved.

[0011] Optionally, judging whether the leaf spring system meets the life requirement according to the simulation stress data and the graded load includes:

[0012] Determine the equivalent life of the leaf spring system through equivalent conversion according to the number of cycles of the graded load in the actual load time series data;

[0013] Calculate the fatigue life of the leaf spring system according to the simulated stress data to obtain the simulated life times of the leaf spring system;

[0014] According to the magnitude relationship between the equivalent life times and the simulation life times, it is determined whether the leaf spring system meets the life requirements.

[0015] Optionally, determining the equivalent life of the leaf spring system by equivalent conversion according to the number of cycles of the graded load in the actual load time series data includes:

[0016] Counting the number of cycles of each of the graded loads by a rain flow counting method; wherein the number of cycles represents the number of times the graded loads appear when the target vehicle drives one circle in the test field;

[0017] According to the number of cycles of all graded loads of the target vehicle under different vehicle weights, a pseudo-damage equivalent calculation is performed on the leaf spring system to obtain a first life number of the leaf spring system; wherein the first life number indicates the number of times the leaf spring system is subjected to all graded loads when the target vehicle travels one circle in the test field;

[0018] According to the ratio of the test field and the actual mileage, the first life times are proportionally converted to obtain the equivalent life times; wherein the equivalent life times are equivalent to the life times of the leaf spring system when the target vehicle reaches the target mileage.

[0019] Optionally, the performing fatigue life calculation on the leaf spring system according to the simulation stress data to obtain the number of simulation lifespans of the leaf spring system comprises:

[0020] According to the simulation stress data, based on a fatigue life formula, obtain the second life number of the leaf spring system under the graded load;

[0021] The second life times under all graded loads under different vehicle weights are added together to obtain the simulation life times of the leaf spring system.

[0022] Optionally, judging whether the leaf spring system meets the life requirement according to the magnitude relationship between the equivalent life times and the simulated life times includes:

[0023] If the equivalent life times are greater than the simulation life times, it means that the leaf spring system has been broken when the target vehicle reaches the target mileage, and it is determined that the leaf spring system does not meet the life requirements.

[0024] Optionally, performing hierarchical statistics based on the load force time series data, the vibration time series data and the wheel jump time series data to obtain a hierarchical load under a preset working condition includes:

[0025] According to the signal amplitude of the load force time series data, the load force time series data is divided into a plurality of levels to obtain a plurality of load force levels;

[0026] According to the signal amplitude of the vibration time series data, the vibration time series data is divided into multiple levels to obtain a plurality of vibration levels;

[0027] According to the signal amplitude of the round hopping timing data, the round hopping timing data is divided into a plurality of levels to obtain a plurality of round hopping levels;

[0028] According to the distribution of the load force level, the vibration level and the wheel hop level in the actual load time series data, the load force level, the vibration level and the wheel hop level that appear in the same time period are combined to obtain the graded load; wherein the time period corresponds to the preset working condition.

[0029] Optionally, a finite element model of the leaf spring system is established in the following manner:

[0030] Performing finite element modeling on the leaf spring system to obtain a leaf spring model;

[0031] Performing finite element modeling on a recirculating ball steering system connected to the leaf spring system to obtain a steering system model;

[0032] Performing finite element modeling on a tire connected to the leaf spring system to obtain a tire model;

[0033] Connection constraints are set between the leaf spring model and the steering system model and between the leaf spring model and the tire model to connect the leaf spring model, the steering system model and the tire model to obtain the finite element model.

[0034] Optionally, the method further comprises:

[0035] Before calculating the simulation stress data, setting the gap in the leaf spring model;

[0036] In the process of calculating the simulation stress data, if a mesh error occurs in the leaf spring model, a parameter to be segmented and an initial parameter are determined from the load force parameter, the vibration acceleration parameter and the wheel jump parameter; wherein the parameter to be segmented is any one of the load force parameter, the vibration acceleration parameter and the wheel jump parameter, and the initial parameter is a parameter of the load force parameter, the vibration acceleration parameter and the wheel jump parameter other than the parameter to be segmented;

[0037] Segmenting the values ​​corresponding to the parameters to be segmented to obtain segmented values ​​corresponding to the parameters to be segmented, and gradually applying the segmented values ​​and the values ​​of the initial parameters to the finite element model to obtain a segmented leaf spring model;

[0038] Regenerate the mesh for a segmented leaf spring model that has mesh errors.

[0039] In a second aspect, an embodiment of the present application provides a leaf spring system life analysis device, the device comprising:

[0040] A data acquisition module, used to acquire actual load time series data of a target vehicle including the leaf spring system in a test field; wherein the actual load time series data includes load force time series data, vibration time series data and wheel hop time series data of the vehicle tire;

[0041] A hierarchical statistics module, used for performing hierarchical statistics based on the load force time series data, the vibration time series data and the wheel hop time series data to obtain a hierarchical load under a preset working condition; wherein the hierarchical load is used to characterize the load force level, vibration level and wheel hop level of the target vehicle under the preset working condition;

[0042] A stress calculation module, used for applying the load force, vibration acceleration and wheel jump corresponding to any graded load to a pre-established finite element model to obtain simulation stress data of the finite element model under any graded load;

[0043] The analysis and diagnosis module is used to determine whether the leaf spring system meets the life requirement based on the simulated stress data and the graded load; wherein the life requirement is that the leaf spring system does not break when the target vehicle reaches a target mileage.

[0044] In a third aspect, an embodiment of the present application provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the method described in any one of the above embodiments by executing the computer instructions.

[0045] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, on which computer instructions are stored, and the computer instructions are used to enable a computer to execute any one of the methods in the above embodiments.

[0046] In a fifth aspect, an embodiment of the present application provides a computer program product, including computer instructions, and the computer instructions are used to enable a computer to execute any one of the methods in the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0048] Figure 1 A step diagram of a leaf spring system life analysis method provided in an embodiment of the present application;

[0049] Figure 2 A diagram showing the steps for determining whether the leaf spring system meets the life requirements in an embodiment of the present application;

[0050] Figure 3 A diagram showing the steps for obtaining the equivalent life times in an embodiment of the present application;

[0051] Figure 4 A diagram showing the steps for obtaining the number of simulated lifespans in an embodiment of the present application;

[0052] Figure 5 A diagram showing the steps of performing hierarchical statistics on actual load time series data in an embodiment of the present application;

[0053] Figure 6 This is a schematic diagram of performing hierarchical statistics on actual load time series data in an embodiment of the present application;

[0054] Figure 7 A diagram showing the steps of establishing a finite element model in an embodiment of the present application;

[0055] Figure 8 A flowchart of establishing a finite element model in an embodiment of the present application;

[0056] Fig. 9 This is a schematic diagram of the assembly of the finite element model in the embodiment of the present application;

[0057] Fig.10 A diagram showing steps for dealing with grid errors during simulation in an embodiment of the present application;

[0058] Fig.11 A module diagram of a leaf spring system life analysis device provided in an embodiment of the present application;

[0059] Fig.12 A schematic diagram of the structure of a computer device provided in an embodiment of the present application.

[0060] Among them, the figure numbers of the drawings in the specification are as follows: 100. Data acquisition module, 200. Hierarchical statistics module, 300. Stress calculation module, 400. Analysis and diagnosis module. DETAILED DESCRIPTION

[0061] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0062] In the process of automobile design and manufacturing, the leaf spring system is a very important part. The leaf spring system is usually installed in the suspension part of the vehicle to support the weight of the vehicle body and absorb the vibration generated by the vehicle during driving and the impact of the road on the vehicle through its own deformation, thereby improving the stability and controllability of the vehicle and enhancing the driving comfort of the user. Affected by the impact of the road surface and the weight of the vehicle body, the leaf spring system will break after a long period of wear, resulting in a direct impact on the vehicle's carrying capacity. Therefore, it is crucial to see whether the life of the leaf spring system meets the requirements. The life of the leaf spring system is generally required to be free of breakage when the target mileage is reached.

[0063] After the leaf spring system is designed, it is necessary to test and analyze whether the leaf spring system meets the life requirements. In the relevant technologies for life analysis of leaf spring systems, usually only the stress data generated by the vehicle containing the leaf spring system to be tested in the test field is detected, and the life times or damage of the leaf spring system is directly calculated based on the stress data. However, in actual situations, the load conditions of the leaf spring system are more complicated. The stress generation in the leaf spring system is related to multiple parameters, and the actual data is very complicated due to the influence of environmental factors and system errors. The results obtained by direct calculation and analysis based only on stress data are also less accurate and cannot fully represent the actual load conditions of the leaf spring system.

[0064] Based on the above problems, the present application provides a leaf spring system life analysis method, device and equipment for performing life analysis on the leaf spring system. The method includes obtaining the actual load time series data of the target vehicle including the leaf spring system in the test field; the actual load time series data includes the load force time series data, vibration time series data and wheel hop time series data of the vehicle tire; the load force time series data, the vibration time series data and the wheel hop time series data are graded and counted to obtain the graded load of the leaf spring system under the preset working conditions; based on the graded load, the equivalent life times of the leaf spring system are obtained by pseudo-damage equivalent calculation, and the simulated life times of the leaf spring system are obtained by stress calculation; the life analysis results of the leaf spring system are obtained by comparing the equivalent life times and the simulated life times. The leaf spring system life analysis method, device and equipment provided in the present application use multiple load parameters to reflect the actual load borne by the leaf spring system, and achieve the technical effect of improving the accuracy of the leaf spring system life classification results by performing graded statistics on the load parameters.

[0065] The leaf spring system life analysis method provided in this specification can be applied to the life analysis of leaf spring systems in various vehicle models. Accordingly, this method can be adaptively modified for different vehicle models. It is understandable that after corresponding modifications, this method can also be used to analyze the life of other systems and parts in the vehicle.

[0066] According to an embodiment of the present application, an embodiment of a leaf spring system life analysis method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0067] In this embodiment, a leaf spring system life analysis method is provided, which can be used to perform life analysis on the leaf spring system based on actual load data. Figure 1 , Figure 1The step diagram of the leaf spring system life analysis method provided in the embodiment of the present application is shown in the figure. The method includes:

[0068] S100. Obtaining actual load time series data borne by a target vehicle including a leaf spring system in a test field; wherein the actual load time series data includes load force time series data, vibration time series data and wheel hop time series data of vehicle tires.

[0069] S200. Perform graded statistics based on the load force time series data, vibration time series data and wheel hop time series data to obtain a graded load under a preset working condition; wherein the graded load is used to characterize the load force level, vibration level and wheel hop level of the target vehicle under the preset working condition.

[0070] S300. Apply the load force, vibration acceleration and wheel jump corresponding to any graded load to the pre-established finite element model to obtain the simulation stress data of the finite element model under any graded load.

[0071] S400. Determine whether the leaf spring system meets the life requirement based on the simulated stress data and the graded load; wherein the life requirement is that the leaf spring system does not break when the target vehicle reaches the target mileage.

[0072] Specifically, the target vehicle includes a leaf spring system, which is the same as the leaf spring system to be tested, and the test is performed to detect the actual load of the leaf spring system under the preset working conditions. The preset working conditions include the vehicle driving mode and the preset road conditions, wherein the vehicle driving mode is the driving mode of the target vehicle when tested in the test field, and the specific forms include driving speed, driving acceleration, turning direction and vehicle load, etc.; the preset road condition is the road state in the test field used to simulate the actual situation, and the load experienced by the target vehicle within a set number of laps in the test field is equivalent to its load in the actual situation.

[0073] Furthermore, when the target vehicle is tested in the test field, sensors corresponding to actual load parameters are also installed in the vehicle body. For example, the target vehicle body may be installed with a wheel center six-component force sensor, an acceleration sensor, and a cable displacement sensor, among which the wheel center six-component force sensor is used to detect the load force on the vehicle tire, the acceleration sensor is used to detect the vibration acceleration of the vehicle tire due to the load, and the cable displacement sensor is used to detect the wheel hop of the vehicle tire. It can be understood that the load force, vibration acceleration, and wheel hop can reflect the specific conditions of the load on the leaf spring system during the test. In other embodiments, other types of sensors can also be used to collect different types of load parameters according to actual needs.

[0074] Specifically, hierarchical statistics is an important method for processing data. Through hierarchical statistics, data can be divided into different levels to reflect the characteristics of the data itself, providing a basis for applied research and thematic mapping. The fundamental purpose of data classification is to distinguish the differences between individuals in the data set, and the process of hierarchical statistics is the process of distinguishing the properties of individuals. Classification is performed according to the signal characteristics in the load force time series data, vibration time series data, and wheel jump time series data, where the signal characteristics are used to describe the actual load time series data, which reflects the characteristics of the actual load parameters, such as the value and the speed of change; illustratively, the signal characteristics can be the amplitude of the signal to represent the value of the actual load parameter; in addition, the signal characteristics can also be the frequency, phase, mean, waveform or periodicity of the signal, etc., which are used to represent the characteristics of different actual load parameters.

[0075] Furthermore, when the preset working condition occurs, the tires of the target vehicle will be subjected to the corresponding actual load, and after the graded statistics, it can be considered that there is a corresponding relationship between the preset working condition and the different actual load levels. Therefore, the graded load corresponding to the preset working condition is obtained through the corresponding relationship between the actual load level and the preset working condition. It can be understood that the graded load represents the load pattern of the target vehicle, and different preset working conditions may correspond to the same graded load. In addition to life analysis, the performance data of the target vehicle and other systems therein can also be obtained by analyzing the frequency, periodicity and change of the graded load.

[0076] Furthermore, the method applies the load force, vibration acceleration and wheel jump corresponding to the graded load to the finite element model of the leaf spring system, and obtains the simulated stress data of the finite element model under any graded load through finite element analysis, so that the life analysis of the leaf spring system can be performed through the simulated stress data. During the finite element analysis process, multiple key points can be set on the finite element model, and different key points can be analyzed separately, wherein the key points can be determined according to actual needs. For example, the key points can be points with the largest stress values ​​under normal circumstances, points that are prone to fracture, and connection points of parts.

[0077] In different embodiments, the leaf spring system may be subjected to different life analysis methods according to actual needs, including but not limited to: calculating the damage of the leaf spring system and calculating the number of times the leaf spring system can withstand the load, etc. It is understandable that if the analysis determines that the damage of the leaf spring system or the number of times the leaf spring system can withstand the load exceeds the upper limit when the target mileage is reached, the leaf spring system has been broken due to the load and cannot meet the purpose of absorbing road impact and reducing vibration, that is, it does not meet the life requirement.

[0078] The leaf spring system life analysis method proposed in this embodiment collects multiple load parameters of the leaf spring system, and after classifying and counting the above load parameters, obtains a graded load representing the leaf spring system, wherein the graded load represents the mode of the load actually borne by the leaf spring system. By counting and classifying the load, the complexity of the data is reduced and the accuracy of the life analysis results is improved. In addition, the graded load is a combination of multiple load parameters that reflect the actual load borne by the leaf spring system in the test field, which can be used to calculate the stress data generated by the leaf spring system under the load. Compared with the direct collection of stress data in the related art, the obtained result is more consistent with the actual load borne by the leaf spring system, and the degree of consistency between the analysis result and the actual situation is improved.

[0079] Reference Figure 2 , Figure 2 The following is a step diagram for judging whether the leaf spring system meets the life requirements in an embodiment of the present application. As an embodiment of the present application, judging whether the leaf spring system meets the life requirements according to the simulated stress data and the graded load includes:

[0080] S410. Determine the equivalent life of the leaf spring system through equivalent conversion according to the number of cycles of the graded load in the actual load time series data.

[0081] S420. Calculate the fatigue life of the leaf spring system according to the simulated stress data to obtain the simulated life times of the leaf spring system.

[0082] S430. Determine whether the leaf spring system meets the life requirements based on the relationship between the equivalent life times and the simulated life times.

[0083] This method determines whether the leaf spring system meets the life requirements by comparing the equivalent life times and the simulated life times. Specifically, the equivalent life times can be obtained based on the data of the target vehicle in the test field, which is equivalent to the life times that the leaf spring system needs to withstand the load when reaching the target mileage, which represents the upper limit of the number of times the leaf spring system withstands the load before breaking; the simulated life times can be obtained by applying the real load data to the finite element model through finite element simulation, which represents the number of times the leaf spring system can withstand the load when reaching the target mileage. It can be understood that when the equivalent life times are greater than the simulated life times, the number of times the leaf spring system withstands the load when reaching the target mileage does not reach the upper limit, that is, no breakage will occur.

[0084] Reference Figure 3 , Figure 3 The figure is a step diagram for obtaining the equivalent life times in the embodiment of the present application. As an embodiment of the present application, the equivalent life times of the leaf spring system are determined by equivalent conversion according to the cycle times of the graded load in the actual load time series data, including:

[0085] S412. Count the number of cycles of each graded load by rain flow counting method; wherein the number of cycles indicates the number of times the graded load appears in one lap of the target vehicle in the test field.

[0086] S414. Perform pseudo-damage equivalent calculation on the leaf spring system according to the number of cycles of all graded loads of the target vehicle under different vehicle weights to obtain the first life number of the leaf spring system; wherein the first life number indicates the number of times the leaf spring system withstands all graded loads when the target vehicle travels one circle in the test field.

[0087] S416. According to the ratio of the test site and the actual mileage, the first life times are proportionally converted to obtain the equivalent life times; wherein the equivalent life times are equivalent to the life times of the leaf spring system when the target vehicle reaches the target mileage.

[0088] The rainflow counting method was proposed by two British engineers, M.Matsuishi and T.Endo, in the 1950s. The main function of the rainflow counting method is to simplify the measured load history into a number of load cycles for fatigue life estimation and fatigue test load spectrum compilation. Specifically, in this embodiment, the rainflow counting method is used to count the number of occurrences of any level of graded load in the signal collected when the target vehicle drives one circle in the test field. The rainflow counting method is used to count the occurrence time and number of graded loads as a periodic load pattern, so as to analyze the impact of actual loads on the leaf spring system and improve the reliability of the analysis results.

[0089] Furthermore, the load force values ​​in the same load force level in the graded load are taken as the same magnitude, and accordingly, the vibration acceleration values ​​in the same vibration level are taken as the same magnitude, and the wheel jump values ​​in the same wheel jump level are taken as the same magnitude; in the above case, different specific values ​​may occur, and loads that are in the same interval during grading are divided into the same level. Therefore, the first life number can be a pseudo-damage equivalent calculation result for the leaf spring system. When the vehicle mileage is the same as the distance of one lap in the test field, the actual life number may be slightly greater than the first life number.

[0090] Furthermore, the distance traveled by the vehicle in the test field can be used to equivalently represent the actual mileage of the vehicle, and there is a certain equivalent conversion ratio between the two. The first life number is multiplied by the above equivalent conversion ratio to obtain the life number of the leaf spring system subjected to the graded load in the actual mileage equivalent to one lap of the test field. The above life number is multiplied by the number of test field laps corresponding to the target mileage to obtain the equivalent life number. It can be understood that the equivalent life number is less than the upper limit of the life number of the leaf spring system when the target vehicle reaches the same actual mileage, thereby ensuring the accuracy of the life analysis results.

[0091] In different embodiments, after obtaining the number of cycles of the graded load by the rain flow counting method, the damage of the leaf spring system that dynamically changes with the graded load can be analyzed by analyzing the cycle pattern of the graded load and the changes between different graded loads, thereby improving the accuracy of the life analysis results.

[0092] Reference Figure 4 , Figure 4 This is a step diagram for obtaining the number of simulated lifespans in an embodiment of the present application. As an embodiment of the present application, fatigue life calculation of a leaf spring system is performed according to simulated stress data to obtain the number of simulated lifespans of the leaf spring system, including:

[0093] S422. According to the simulation stress data, the second life number of the leaf spring system under the graded load is obtained based on the fatigue life formula.

[0094] S424. Add up the second life times under all graded loads under different vehicle weights to obtain the simulation life times of the leaf spring system.

[0095] Specifically, the fatigue life formula is in the following form:

[0096] σ i m ×N i =C

[0097] Among them, σ i is the simulation stress data at the i-th key point; N i is the second life number at the i-th key point; m and C are constants related to the material and loading form of the leaf spring system. Based on the fatigue life formula, the corresponding second life number can be obtained according to the simulated stress data under any graded load.

[0098] Furthermore, a three-dimensional classification statistical model is established with graded loads, vehicle weight and key points in the leaf spring system as variables, wherein the vehicle weight includes any one of empty, half-loaded, fully loaded and overloaded. By changing the weight carried by the target vehicle, the actual load time series data under different vehicle weights can be collected, and then the second life times corresponding to all graded loads under different vehicle weights can be obtained.

[0099] Furthermore, the simulation life times obtained in step S424 are about any key point in the leaf spring system, and are in the following form:

[0100]

[0101] Wherein, N represents the number of simulated lifespans at the i-th key point; the number of simulated lifespans at any key point in the leaf spring system is the sum of the second lifespans of the key point under all combinations of graded loads and vehicle weight, which represents the number of lifespans of the key point in the leaf spring system that has completed the endurance road test at the test site. The distance of the endurance road test can be equivalent to the target mileage.

[0102] It should be noted that the simulation stress data in this embodiment can be obtained by correcting and calculating the average stress and amplitude stress in the leaf spring system, and its form is as follows:

[0103]

[0104] in, is the amplitude stress at the i-th key point; is the average stress at the i-th key point; σ s is the yield strength of the leaf spring system material; mean stress and amplitude stress It is obtained by finite element calculation after applying graded loads to the finite element model.

[0105] As an embodiment of the present application, judging whether the leaf spring system meets the life requirement according to the relationship between the equivalent life times and the simulated life times includes:

[0106] S432. If the equivalent life times are greater than the simulated life times, it means that the leaf spring system has broken when the target vehicle reaches the target mileage, and it is determined that the leaf spring system does not meet the life requirements.

[0107] Specifically, from the above description, it can be known that the equivalent life times represent the number of times the leaf spring system needs to withstand the load when the target mileage is reached, and the simulation life times represent the number of times the leaf spring system can withstand the load when the target mileage is reached.

[0108] It is understandable that if the equivalent life times are less than the simulated life times, it means that the number of times the leaf spring system bears the load when the target mileage is reached has not reached the upper limit of the number of times it can withstand, and the life of the leaf spring system still has a certain safety margin, and it is in an acceptable working state; if the equivalent life times are greater than the simulated life times, it means that the number of times the leaf spring system bears the load when the target mileage is reached exceeds the upper limit of the number of times it can withstand, then when the number of times the leaf spring system bears the load exceeds the upper limit of the number of times it can withstand, the leaf spring system may break, causing it to be in a dangerous state and unable to meet working needs. If the leaf spring system may or has broken when the target vehicle reaches the target mileage, the leaf spring system does not meet the life requirements.

[0109] Reference Figure 5 , Figure 5This is a step diagram for performing hierarchical statistics on actual load time series data in an embodiment of the present application. As an embodiment of the present application, hierarchical statistics are performed based on load force time series data, vibration time series data, and wheel jump time series data to obtain hierarchical loads under preset working conditions, including:

[0110] S210. According to the signal amplitude of the load force time series data, the load force time series data is divided into multiple levels to obtain a plurality of load force levels.

[0111] S220. According to the signal amplitude of the vibration time series data, the vibration time series data is divided into multiple levels to obtain a plurality of vibration levels.

[0112] S230. According to the signal amplitude of the round hop timing data, the round hop timing data is divided into a plurality of levels to obtain a plurality of round hop levels.

[0113] S240. According to the distribution of load force level, vibration level and wheel jump level in the actual load time series data, the load force level, vibration level and wheel jump level appearing in the same time period are combined to obtain a graded load; wherein the time period corresponds to a preset working condition.

[0114] Specifically, in order to equivalently represent the damage suffered by the leaf spring system of the target vehicle when it reaches the target mileage, the preset working conditions experienced by the target vehicle are pre-set. When the target vehicle experiences the preset working conditions, the sensor installed on the target vehicle will collect signals about the actual load parameters. The actual load parameters obtained by the sensor are a series of time series signals, whose amplitudes represent the values ​​of the actual load parameters, and the duration of the signal is short. For different actual load parameters, the amplitude of the time series signal is divided into multiple intervals of the same size with the maximum amplitude in the corresponding time series signal as the upper limit, and the corresponding actual load level is determined according to the interval where the signal is located.

[0115] Furthermore, in the actual load time series data, the time period in which the preset working condition occurs is known, so the actual load time series data can be divided according to the known time period. For the load force signal, vibration signal and wheel hop signal that appear in the same time period, it can be considered that the above signals are collected at the same time and correspond to the same preset working condition. Therefore, the actual load levels corresponding to the above signals can be combined to obtain a graded load including the load force level, vibration level and wheel hop level to represent the actual load caused by the preset working condition on the target vehicle.

[0116] For example, refer to Figure 6 , Figure 6This is a schematic diagram of hierarchical statistics of actual load time series data in an embodiment of the present application. As shown in the figure, the signals in the load force time series data and the vibration time series data can be divided into 7 levels according to the signal amplitude, and the signals in the wheel jump time series data can be divided into 4 levels according to the signal amplitude. The load force level, vibration level and wheel jump level that appear in the same time period are combined to obtain a graded load. According to the actual load parameters, a three-dimensional classification statistical model for equivalent calculation is established. In this three-dimensional classification statistical model, each three-dimensional grid corresponds to a graded load, indicating the corresponding load force level, vibration level and wheel jump level.

[0117] Reference Figure 7 , Figure 7 This is a step diagram for establishing a finite element model in an embodiment of the present application. As an embodiment of the present application, a finite element model of a leaf spring system is established in the following manner:

[0118] S310. Perform finite element modeling on the leaf spring system to obtain a leaf spring model.

[0119] S320. Perform finite element modeling on the recirculating ball steering system connected to the leaf spring system to obtain a steering system model.

[0120] S330. Perform finite element modeling on the tire connected to the leaf spring system to obtain a tire model.

[0121] S340. Setting connection constraints between the leaf spring model and the steering system model and between the leaf spring model and the tire model to connect the leaf spring model, the steering system model and the tire model to obtain a finite element model.

[0122] Specifically, refer to Figure 8 , Figure 8 This is a flow chart for establishing a finite element model in an embodiment of the present application. After obtaining the leaf spring model, the stiffness curves of each elastic element in the leaf spring system are input into the leaf spring model to perform stiffness verification on the leaf spring model. If the leaf spring model does not meet the stiffness requirements, the leaf spring model is returned for correction. If the leaf spring model meets the stiffness requirements, the next step is performed.

[0123] Furthermore, constraints are imposed on the leaf spring model to clamp the leaf spring model in a free state and obtain a clamped leaf spring model. The clamped leaf spring model is aligned with the hard point on the unloaded vehicle body so that the clamped leaf spring model is connected to the tire model to assemble the clamped leaf spring model to the vehicle body, and the wheel center constraint and temporary constraint are turned off to allow the tire model to droop freely. The unsprung mass is loaded on the wheel center of the tire model, and the sprung mass is loaded on the wheel edge of the tire model. The load on the leaf spring model at this time is calculated to obtain the unloaded state result. The unloaded state result is verified. If the unloaded state result is incorrect, it means that there is an error in the leaf spring model and it is necessary to return to correct the leaf spring model. If the unloaded state result is correct, it means that the leaf spring model is correct. At this time, the leaf spring model is connected to the steering system model to obtain a finite element model. For example, refer to Fig. 9 , Fig. 9 This is a schematic diagram of the assembly of the finite element model in the embodiment of the present application, as shown in the figure, Fig. 9 The tire model is represented by the tire hub. Through the above analysis and assembly, a finite element model is obtained. By performing finite element analysis on the finite element model, the life analysis result of the leaf spring system can be obtained.

[0124] Reference Fig.10 , Fig.10 This is a step diagram of dealing with grid errors during simulation in an embodiment of the present application. As an embodiment of the present application, the method further includes:

[0125] S350. Before calculating the simulation stress data, set the gap in the leaf spring model.

[0126] S360. In the process of calculating the simulation stress data, if a mesh error occurs in the leaf spring model, the parameters to be segmented and the initial parameters are determined from the load force parameters, vibration acceleration parameters and wheel jump parameters; wherein the parameters to be segmented are any one of the load force parameters, vibration acceleration parameters and wheel jump parameters, and the initial parameters are the parameters of the load force parameters, vibration acceleration parameters and wheel jump parameters except the parameters to be segmented.

[0127] S370. Segment the values ​​corresponding to the parameters to be segmented to obtain segmented values ​​corresponding to the parameters to be segmented, and gradually apply the segmented values ​​and the values ​​of the initial parameters to the finite element model to obtain a segmented leaf spring model.

[0128] S380. Regenerate the mesh for the segmented leaf spring model with mesh errors.

[0129] Specifically, in the finite element analysis process, in order to avoid the problem of mesh errors caused by large deformation of the leaf spring model after being subjected to graded loads, which leads to the problem of non-convergence of the finite element analysis, the gap in the leaf spring model is first set before calculating the simulation stress data to avoid conflicts between the leaf springs in the leaf spring model. For example, if the leaf spring below is deformed, the leaf spring above is forced to displace according to the deformation amount and gap size of the leaf spring below.

[0130] Furthermore, in the process of calculating the simulation stress data, if the leaf spring model has a large deformation and causes a mesh error, the actual load parameters in the graded load are screened to determine the actual load parameters that cause the leaf spring system to have a mesh error as the parameters to be segmented. It can be understood that directly applying the values ​​of the parameters to be segmented to the leaf spring model will cause mesh errors, so it is necessary to segment the values ​​corresponding to the parameters to be segmented to obtain the corresponding segmented values, and then gradually apply the segmented values ​​and the values ​​of the initial parameters to the finite element model to obtain a segmented leaf spring model.

[0131] Furthermore, it is determined whether a mesh error occurs in the segmented leaf spring model. If a mesh error occurs in the segmented leaf spring model corresponding to any segmented value, the mesh of the segmented leaf spring model in the previous segment is regenerated so that when any segmented value is applied again, the segmented leaf spring model will not have a mesh error, thereby solving the problem of difficulty in convergence of nonlinear analysis when large deformation and strong contact occur in the leaf spring model.

[0132] Accordingly, please refer to Fig.11 , the embodiment of the present application provides a leaf spring system life analysis device, the device comprising:

[0133] The data acquisition module 100 is used to acquire the actual load time series data borne by the target vehicle including the leaf spring system in the test field; wherein the actual load time series data includes the load force time series data, vibration time series data and wheel hop time series data of the vehicle tire.

[0134] The graded statistics module 200 is used to perform graded statistics based on the load force time series data, the vibration time series data and the wheel hop time series data to obtain the graded load under the preset working conditions; wherein the graded load is used to characterize the load force level, vibration level and wheel hop level of the target vehicle under the preset working conditions.

[0135] The stress calculation module 300 is used to apply the load force, vibration acceleration and wheel jump corresponding to any graded load to the pre-established finite element model to obtain the simulation stress data of the finite element model under any graded load.

[0136] The analysis and diagnosis module 400 is used to determine whether the leaf spring system meets the life requirement based on the simulated stress data and the graded load; wherein the life requirement is that the leaf spring system does not break when the target vehicle reaches the target mileage.

[0137] In some optional embodiments, the analysis and diagnosis module 400 includes:

[0138] The equivalent calculation unit is used to determine the equivalent life times of the leaf spring system through equivalent conversion according to the number of cycles of the graded load in the actual load time series data.

[0139] The simulation calculation unit is used to calculate the fatigue life of the leaf spring system according to the simulation stress data to obtain the simulation life times of the leaf spring system.

[0140] The judgment and analysis unit is used to judge whether the leaf spring system meets the life requirement according to the size relationship between the equivalent life times and the simulated life times.

[0141] In some optional implementations, the equivalent computing unit includes:

[0142] The load counting subunit is used to count the number of cycles of each load in a graded manner through a rain flow counting method; wherein the number of cycles represents the number of times the graded load appears in one lap of the target vehicle in the test field.

[0143] The damage equivalent calculation subunit is used to perform pseudo-damage equivalent calculation on the leaf spring system according to the number of cycles of all graded loads of the target vehicle under different vehicle weights, and obtain the first life number of the leaf spring system; wherein the first life number indicates the number of times the leaf spring system is subjected to all graded loads in one circle of the target vehicle in the test field.

[0144] The proportional conversion subunit is used to convert the first life times according to the ratio of the test site and the actual mileage to obtain the equivalent life times; wherein the equivalent life times is equivalent to the life times of the leaf spring system when the target vehicle reaches the target mileage.

[0145] In some optional implementations, the simulation calculation unit includes:

[0146] The fatigue life calculation subunit is used to obtain the second life times of the leaf spring system under graded loads based on the fatigue life formula according to the simulation stress data.

[0147] The life times statistics subunit is used to add up the second life times under all graded loads under different vehicle weights to obtain the simulation life times of the leaf spring system.

[0148] In some optional implementations, the judgment and analysis unit includes:

[0149] The life requirement judgment subunit is used to judge whether the leaf spring system meets the life requirement. If the equivalent life times are greater than the simulation life times, it means that the leaf spring system has broken when the target vehicle reaches the target mileage, and it is judged that the leaf spring system does not meet the life requirement.

[0150] In some optional implementations, the hierarchical statistics module 200 includes:

[0151] The load force grading unit is used to divide the load force time series data into multiple levels according to the signal amplitude of the load force time series data to obtain a plurality of load force levels.

[0152] The vibration classification unit is used to classify the vibration time series data into multiple levels according to the signal amplitude of the vibration time series data to obtain a plurality of vibration levels.

[0153] The round hopping classification unit is used to classify the round hopping timing data into multiple levels according to the signal amplitude of the round hopping timing data to obtain a plurality of round hopping levels.

[0154] The graded combination unit is used to combine the load force level, vibration level and wheel jump level that appear in the same time period according to the distribution of the load force level, vibration level and wheel jump level in the actual load time series data to obtain a graded load; wherein the time period corresponds to the preset working condition.

[0155] In some optional implementations, the stress calculation module 300 includes:

[0156] The leaf spring modeling unit is used to perform finite element modeling on the leaf spring system to obtain a leaf spring model.

[0157] The steering system modeling unit is used to perform finite element modeling on a recirculating ball steering system connected to a leaf spring system to obtain a steering system model.

[0158] The tire modeling unit is used to perform finite element modeling on the tire connected to the leaf spring system to obtain a tire model.

[0159] The model connection unit is used to set connection constraints between the leaf spring model and the steering system model and between the leaf spring model and the tire model, so as to connect the leaf spring model, the steering system model and the tire model to obtain a finite element model.

[0160] In some optional embodiments, the stress calculation module 300 further includes

[0161] The gap setting unit is used to set the gap in the leaf spring model before calculating the simulation stress data.

[0162] The parameter selection unit is used to determine the parameters to be segmented and the initial parameters from the load force parameters, vibration acceleration parameters and wheel jump parameters if a mesh error occurs in the leaf spring model during the calculation of the simulation stress data; wherein the parameters to be segmented are any one of the load force parameters, vibration acceleration parameters and wheel jump parameters, and the initial parameters are parameters other than the parameters to be segmented from the load force parameters, vibration acceleration parameters and wheel jump parameters.

[0163] The segmented applying unit is used to segment the values ​​corresponding to the parameters to be segmented, obtain the segmented values ​​corresponding to the parameters to be segmented, and gradually apply the segmented values ​​and the values ​​of the initial parameters to the finite element model to obtain the segmented leaf spring model.

[0164] The mesh reconstruction unit is used to regenerate the mesh for the segmented leaf spring model with mesh errors.

[0165] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0166] The leaf spring system life analysis device in this embodiment is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0167] See also Fig.12 , Fig.12 It is a structural diagram of a computer device provided by an embodiment of the present application, and the computer device includes: one or more processors 10, a memory 20, and an interface for connecting various components, including a high-speed interface and a low-speed interface. The various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process instructions executed in the computer device, including instructions stored in or on the memory to display graphical information of the GUI on an external input / output device (such as a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Fig.12 A processor 10 is taken as an example.

[0168] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0169] The memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0170] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0171] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0172] The computer device further comprises a communication interface 30 for the computer device to communicate with other devices or a communication network.

[0173] The embodiment of the present application also provides a computer-readable storage medium. The above method according to the embodiment of the present application can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0174] The embodiment of the present application provides a computer program product, which includes computer instructions, which are stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the method of any embodiment of the present application.

[0175] Although the embodiments of the present application are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations are all within the scope defined by the appended claims.

[0176] The systems, devices, modules or units described in the above embodiments may be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, the computer may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0177] For the convenience of description, the above device is described in various units according to their functions. Of course, when implementing the present application, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0178] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0179] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1A device that provides the functions specified in a block or multiple blocks.

[0180] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0181] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0182] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0183] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0184] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

[0185] Although the embodiments of the present application have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A leaf spring system life analysis method, characterized in that: The method comprises: Acquire actual load time series data of the target vehicle including the leaf spring system in the test field; wherein the actual load time series data includes load force time series data, vibration time series data and wheel hop time series data of the vehicle tire; Based on the load force time series data, the vibration time series data and the wheel hop time series data, hierarchical statistics are performed to obtain a hierarchical load under a preset working condition; wherein the hierarchical load is used to characterize the load force level, vibration level and wheel hop level of the target vehicle under the preset working condition; Apply the load force, vibration acceleration and wheel jump corresponding to any graded load to a pre-established finite element model to obtain simulation stress data of the finite element model under the any graded load; According to the simulation stress data and the graded load, it is determined whether the leaf spring system meets the life requirement; wherein the life requirement is that the leaf spring system does not break when the target vehicle reaches a target mileage.

2. The method according to claim 1, characterized in that The step of judging whether the leaf spring system meets the life requirement according to the simulated stress data and the graded load includes: Determine the equivalent life of the leaf spring system through equivalent conversion according to the number of cycles of the graded load in the actual load time series data; Calculate the fatigue life of the leaf spring system according to the simulated stress data to obtain the simulated life times of the leaf spring system; According to the magnitude relationship between the equivalent life times and the simulation life times, it is determined whether the leaf spring system meets the life requirements.

3. The method according to claim 2, characterized in that The determining the equivalent life of the leaf spring system by equivalent conversion according to the number of cycles of the graded load in the actual load time series data comprises: Counting the number of cycles of each of the graded loads by a rain flow counting method; wherein the number of cycles represents the number of times the graded loads appear when the target vehicle drives one circle in the test field; According to the number of cycles of all graded loads of the target vehicle under different vehicle weights, a pseudo-damage equivalent calculation is performed on the leaf spring system to obtain a first life number of the leaf spring system; wherein the first life number indicates the number of times the leaf spring system is subjected to all graded loads when the target vehicle travels one circle in the test field; According to the ratio of the test field and the actual mileage, the first life times are proportionally converted to obtain the equivalent life times; wherein the equivalent life times are equivalent to the life times of the leaf spring system when the target vehicle reaches the target mileage.

4. The method according to claim 2, characterized in that: The step of calculating the fatigue life of the leaf spring system according to the simulated stress data to obtain the number of simulated lifespans of the leaf spring system comprises: According to the simulation stress data, based on a fatigue life formula, obtain the second life number of the leaf spring system under the graded load; The second life times under all graded loads under different vehicle weights are added together to obtain the simulation life times of the leaf spring system.

5. The method according to claim 2, characterized in that: The step of judging whether the leaf spring system meets the life requirement according to the relationship between the equivalent life times and the simulated life times includes: If the equivalent life times are greater than the simulation life times, it means that the leaf spring system has been broken when the target vehicle reaches the target mileage, and it is determined that the leaf spring system does not meet the life requirements.

6. The method according to claim 1, characterized in that The step of performing hierarchical statistics based on the load force time series data, the vibration time series data and the wheel jump time series data to obtain a hierarchical load under a preset working condition includes: According to the signal amplitude of the load force time series data, the load force time series data is divided into a plurality of levels to obtain a plurality of load force levels; According to the signal amplitude of the vibration time series data, the vibration time series data is divided into multiple levels to obtain a plurality of vibration levels; According to the signal amplitude of the round hopping timing data, the round hopping timing data is divided into a plurality of levels to obtain a plurality of round hopping levels; According to the distribution of the load force level, the vibration level and the wheel hop level in the actual load time series data, the load force level, the vibration level and the wheel hop level that appear in the same time period are combined to obtain the graded load; wherein the time period corresponds to the preset working condition.

7. The method according to any one of claims 1 to 6, characterized in that The finite element model of the leaf spring system is established in the following way: Performing finite element modeling on the leaf spring system to obtain a leaf spring model; Performing finite element modeling on a recirculating ball steering system connected to the leaf spring system to obtain a steering system model; Performing finite element modeling on a tire connected to the leaf spring system to obtain a tire model; Connection constraints are set between the leaf spring model and the steering system model and between the leaf spring model and the tire model to connect the leaf spring model, the steering system model and the tire model to obtain the finite element model.

8. The method according to claim 7, characterized in that The method further comprises: Before calculating the simulation stress data, setting the gap in the leaf spring model; In the process of calculating the simulation stress data, if a mesh error occurs in the leaf spring model, a parameter to be segmented and an initial parameter are determined from the load force parameter, the vibration acceleration parameter and the wheel jump parameter; wherein the parameter to be segmented is any one of the load force parameter, the vibration acceleration parameter and the wheel jump parameter, and the initial parameter is a parameter of the load force parameter, the vibration acceleration parameter and the wheel jump parameter other than the parameter to be segmented; Segmenting the values ​​corresponding to the parameters to be segmented to obtain segmented values ​​corresponding to the parameters to be segmented, and gradually applying the segmented values ​​and the values ​​of the initial parameters to the finite element model to obtain a segmented leaf spring model; Regenerate the mesh for a segmented leaf spring model that has mesh errors.

9. A leaf spring system life analysis device, characterized in that: The device comprises: A data acquisition module, used to acquire actual load time series data of a target vehicle including the leaf spring system in a test field; wherein the actual load time series data includes load force time series data, vibration time series data and wheel hop time series data of the vehicle tire; A hierarchical statistics module, used for performing hierarchical statistics based on the load force time series data, the vibration time series data and the wheel hop time series data to obtain a hierarchical load under a preset working condition; wherein the hierarchical load is used to characterize the load force level, vibration level and wheel hop level of the target vehicle under the preset working condition; A stress calculation module, used for applying the load force, vibration acceleration and wheel jump corresponding to any graded load to a pre-established finite element model to obtain simulation stress data of the finite element model under any graded load; The analysis and diagnosis module is used to determine whether the leaf spring system meets the life requirement based on the simulated stress data and the graded load; wherein the life requirement is that the leaf spring system does not break when the target vehicle reaches a target mileage.

10. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the method according to any one of claims 1 to 8 by executing the computer instructions.

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