Automobile bumper parameter determination method and system

Abstract

The invention is suitable for the technical field of vehicles, and provides an automobile bumper parameter determination method and system, and the method comprises the following steps: constructing an automobile bumper with different curvature radiuses and a three-dimensional simulation model of a whole automobile, and dividing the three-dimensional simulation model into a plurality of units through employing a finite element analysis method, so as to simulate the stress distribution and deformation in a collision process; configuring collision parameters, wherein the collision parameters comprise a collision speed, a collision angle and a collision object; simulation software is operated, the conditions of bumpers with different curvature radiuses in the collision process are simulated, a collision simulation result is recorded, and the collision simulation result comprises the deformation condition and energy absorption information of the bumpers; preliminarily determining the curvature radius range of the automobile bumper based on the collision simulation result; and the measurement precision and the measurement stability of the radar in the automobile bumper within the curvature radius range are determined, and the optimal curvature radius range is determined. According to the invention, while the collision performance of the bumper is ensured, the normal work of the radar sensor is also ensured.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a method and system for determining parameters of an automobile bumper. Background Art

[0002] With the rapid development of the automobile industry and the increasing demand of consumers for automobile safety performance, the design and optimization of automobile bumpers, as an important part of the vehicle's passive safety system, have become particularly important. Traditional bumper design mainly relies on experience and physical collision tests, which is not only costly and time-consuming, but also difficult to fully cover various collision conditions, limiting the flexibility and accuracy of bumper design.

[0003] In recent years, with the rapid development of computer technology and simulation software, 3D simulation technology has gradually become an important means of automobile design and safety assessment. By building a high-precision 3D simulation model, key parameters such as stress distribution, deformation, and energy absorption of the car during a collision can be simulated, providing strong support for the design and optimization of the bumper.

[0004] However, in practical applications, the design of automobile bumpers is not limited to the optimization of strength and energy absorption performance, but also needs to consider compatibility with other vehicle systems. In particular, with the popularization of autonomous driving technology, the integration and mutual interference of bumpers and sensors such as radars are becoming increasingly prominent. The curvature radius of the bumper not only affects its own collision performance, but may also have a significant impact on the measurement accuracy and stability of the radar, thereby affecting the reliability and safety of the autonomous driving system. Therefore, it is necessary to provide a method and system for determining automobile bumper parameters to solve the above problems. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a method and system for determining parameters of an automobile bumper to solve the problems existing in the above-mentioned background technology.

[0006] The present invention is achieved by a method for determining parameters of a vehicle bumper, the method comprising the following steps: Constructing three-dimensional simulation models of automobile bumpers and the entire vehicle with different curvature radii, and dividing the three-dimensional simulation models into multiple units using finite element analysis to simulate stress distribution and deformation during a collision; Configure collision parameters, including collision speed, collision angle and collision object; Run the simulation software to simulate the collision of bumpers with different curvature radii and record the collision simulation results, which include the deformation of the bumper and the energy absorption information; Preliminarily determine the curvature radius range of the car bumper based on the collision simulation results; Determine the measurement accuracy and measurement stability of the radar in the car bumper within the curvature radius range and determine the optimal curvature radius range.

[0007] As a further solution of the present invention: the step of recording the collision simulation results specifically includes: Recording the deformation of the bumper during the collision, wherein the deformation includes the maximum deformation amount, deformation speed and deformation mode; The deformation degree is calculated based on the maximum deformation, and the deformation degree is equal to the ratio of the maximum deformation to the total length of the bumper; Recording energy absorption information of the bumper during a collision, wherein the energy absorption information includes total absorbed energy and energy absorption rate; The energy absorption rate is calculated based on the total absorbed energy, and the energy absorption rate is equal to the ratio of the total absorbed energy to the total collision energy.

[0008] As a further solution of the present invention: the step of preliminarily determining the curvature radius range of the automobile bumper based on the collision simulation results specifically includes: The regression model is trained based on historical collision data. The independent variable of the regression model is the radius of curvature, and the dependent variables are deformation speed, deformation degree, energy absorption rate and energy absorption rate. The collision simulation results are grouped according to the curvature radius and variance analysis is performed. The curvature radius range is determined based on the variance analysis results.

[0009] As a further solution of the present invention: the step of determining the measurement accuracy and measurement stability of the radar in the automobile bumper within the curvature radius range specifically includes: Record the radar sensor's measurements at different distances and angles, and record the measurements under different driving scenarios and obstacles; Comparing the measured value with the corresponding standard value to obtain the measurement accuracy of the radar sensor at different curvature radii; Record the measured values ​​of radar sensors under different environmental conditions and analyze the changing trends of the measured values; record the measured values ​​of radar sensors during long-term operation to determine drift and error accumulation; The measurement stability of the radar sensor at different curvature radii is obtained based on the change trend, drift and error accumulation.

[0010] As a further solution of the present invention: the step of determining the optimal range of curvature radius specifically includes: The measurement accuracy and stability of the radar under different curvature radii are displayed through trend graphs; An evaluation standard curve for measurement accuracy and measurement stability is added to the trend chart, and the curvature radius that meets the evaluation standard curve is determined to obtain the optimal curvature radius range.

[0011] Another object of the present invention is to provide a system for determining parameters of an automobile bumper, the system comprising: A simulation model building module is used to build a three-dimensional simulation model of a car bumper with different curvature radii and a whole vehicle, and divide the three-dimensional simulation model into multiple units using a finite element analysis method to simulate stress distribution and deformation during a collision; A collision parameter configuration module, used to configure collision parameters, wherein the collision parameters include collision speed, collision angle and collision object; The collision simulation result module is used to run the simulation software, simulate the bumpers with different curvature radii during the collision process, and record the collision simulation results, which include the deformation of the bumper and the energy absorption information; The curvature radius range module is used to preliminarily determine the curvature radius range of the car bumper based on the collision simulation results; The optimal curvature radius module is used to determine the measurement accuracy and measurement stability of the radar in the car bumper within the curvature radius range and determine the optimal curvature radius range.

[0012] As a further solution of the present invention: the collision simulation result module includes: A deformation recording unit, used to record the deformation of the bumper during a collision, wherein the deformation includes a maximum deformation amount, a deformation speed and a deformation mode; A deformation degree calculation unit, used for calculating the deformation degree according to the maximum deformation, where the deformation degree is equal to the ratio of the maximum deformation to the total length of the bumper; An energy absorption information unit, used to record the energy absorption information of the bumper during the collision, wherein the energy absorption information includes the total absorbed energy and the energy absorption rate; The energy absorption rate calculation unit is used to calculate the energy absorption rate according to the total absorbed energy, and the energy absorption rate is equal to the ratio of the total absorbed energy to the total collision energy.

[0013] As a further solution of the present invention: the curvature radius range module includes: A regression model training unit, used for training a regression model based on historical collision data, wherein the independent variable of the regression model is the radius of curvature, and the dependent variables are the deformation speed, deformation degree, energy absorption rate and energy absorption rate; The variance analysis unit is used to group the collision simulation results according to the curvature radius and perform variance analysis, and determine the curvature radius range through the variance analysis results.

[0014] As a further solution of the present invention: the optimal curvature radius module includes: A first measurement value recording unit, used to record the measurement values ​​of the radar sensor at different distances and angles, and to record the measurement values ​​under different driving scenarios and obstacles; A measurement accuracy determination unit, used to compare the measurement value with a corresponding standard value to obtain the measurement accuracy of the radar sensor at different curvature radii; The second measurement value recording unit is used to record the measurement values ​​of the radar sensor under different environmental conditions and analyze the change trend of the measurement values; record the measurement values ​​of the radar sensor during long-term operation, determine the drift and error accumulation; The measurement stability determination unit is used to obtain the measurement stability of the radar sensor at different curvature radii according to the change trend, drift situation and error accumulation.

[0015] As a further solution of the present invention: the optimal curvature radius module also includes: A trend graph display unit is used to display the measurement accuracy and stability of the radar under different curvature radii through trend graphs; The optimal curvature radius unit is used to add an evaluation standard curve of measurement accuracy and measurement stability to the trend chart, determine the curvature radius that meets the evaluation standard curve, and obtain the optimal curvature radius range.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention constructs a three-dimensional simulation model of a car bumper and a whole vehicle with different curvature radii, and uses the finite element analysis method to simulate the collision process. It can not only accurately evaluate the collision performance of the bumper, but also preliminarily determine the curvature radius range of the bumper based on the collision simulation results. Furthermore, the influence of the bumper curvature radius on the radar measurement accuracy and stability is considered, and the optimal curvature radius range is determined through actual measurement and evaluation, thereby ensuring the collision performance of the bumper while also ensuring the normal operation of sensors such as radar. This method not only improves the scientificity and accuracy of the bumper design, but also provides a strong guarantee for the safety and reliability of self-driving cars. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention is a flow chart of a method for determining parameters of a vehicle bumper.

[0018] Figure 2 The present invention is a flowchart for recording collision simulation results in a method for determining parameters of a vehicle bumper.

[0019] Figure 3 The present invention is a flow chart for determining the curvature radius range of an automobile bumper in a method for determining automobile bumper parameters.

[0020] Figure 4The present invention is a flow chart for determining the measurement accuracy and measurement stability in a method for determining parameters of an automobile bumper.

[0021] Figure 5 The present invention is a flow chart for determining an optimal curvature radius range in a method for determining parameters of an automobile bumper.

[0022] Figure 6 The schematic diagram of the structure of a system for determining parameters of a car bumper is shown in FIG. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0024] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0025] like Figure 1 As shown, an embodiment of the present invention provides a method for determining parameters of a vehicle bumper, the method comprising the following steps: S100, constructing a three-dimensional simulation model of a car bumper with different curvature radii and a whole vehicle, and dividing the three-dimensional simulation model into a plurality of units using a finite element analysis method to simulate stress distribution and deformation during a collision process; S200, configuring collision parameters, where the collision parameters include collision speed, collision angle, and collision object; S300, running simulation software to simulate the conditions of bumpers with different curvature radii during a collision, and recording collision simulation results, which include deformation conditions and energy absorption information of the bumper; S400, preliminarily determining a curvature radius range of the vehicle bumper based on the collision simulation result; S500, determining the measurement accuracy and measurement stability of the radar in the car bumper within the curvature radius range, and determining the optimal curvature radius range.

[0026] It should be noted that with the rapid development of computer technology and simulation software, three-dimensional simulation technology has gradually become an important means of automobile design and safety assessment. By constructing a high-precision three-dimensional simulation model, key parameters such as stress distribution, deformation, and energy absorption of the car during a collision can be simulated, providing strong support for the design and optimization of the bumper. However, in practical applications, the design of automobile bumpers is not limited to the optimization of strength and energy absorption performance, but also needs to consider compatibility with other vehicle systems. In particular, with the popularization of autonomous driving technology, the integration and mutual interference of bumpers and sensors such as radars have become increasingly prominent. The radius of curvature of the bumper not only affects its own collision performance, but may also have a significant impact on the measurement accuracy and stability of the radar, thereby affecting the reliability and safety of the autonomous driving system.

[0027] In the embodiment of the present invention, firstly, high-precision CAD software (such as SolidWorks, CATIA, etc.) is used to construct a three-dimensional simulation model of a car bumper and a whole vehicle with different curvature radii. The whole vehicle model should consider factors such as the body structure, suspension system, tires and chassis to simulate the real collision environment, and then the finite element analysis (FEA) method is used to divide the three-dimensional simulation model into multiple small units to accurately simulate the stress distribution and deformation during the collision process. Then, the collision parameters need to be configured, and the collision parameters include collision speed, collision angle and collision object. According to industry standards or regulatory requirements, multiple speed levels (such as 50km / h, 60km / h, etc.) are set for simulation. The collision angle needs to consider multiple angles such as frontal collision, side collision and oblique collision to comprehensively evaluate the performance of the bumper; collision objects with different masses and stiffness (such as rigid barriers, deformable barriers, etc.) are used to simulate different types of collision scenes.

[0028] Then run the simulation software (such as LS-DYNA, PAM-CRASH, etc.) to simulate the bumpers with different curvature radii during the collision process, and record the collision simulation results. The collision simulation results include the deformation of the bumper and the energy absorption information. Based on the collision simulation results, the curvature radius range of the car bumper is preliminarily determined. Here, statistical analysis methods (such as regression analysis, variance analysis, etc.) are used to analyze the deformation and energy absorption information of the bumper under different curvature radii. According to the analysis results, the curvature radius range that meets the collision performance requirements is preliminarily determined. Then it is necessary to install the radar sensor on the bumper within the curvature radius range, and conduct static and dynamic tests to obtain the measurement accuracy and measurement stability of the radar in the car bumper, and then determine the optimal curvature radius range, so as to ensure that the measurement accuracy and measurement stability of the radar meet the requirements.

[0029] like Figure 2 As shown, as a preferred embodiment of the present invention, the step of recording the collision simulation result specifically includes: S301, recording the deformation of the bumper during the collision, wherein the deformation includes a maximum deformation amount, a deformation speed, and a deformation mode; S302, calculating the deformation degree according to the maximum deformation, where the deformation degree is equal to the ratio of the maximum deformation to the total length of the bumper; S303, recording energy absorption information of the bumper during the collision, wherein the energy absorption information includes total absorbed energy and energy absorption rate; S304, calculating an energy absorption rate according to the total absorbed energy, where the energy absorption rate is equal to the ratio of the total absorbed energy to the total collision energy.

[0030] Specifically, the deformation of the bumper during the collision is recorded, and the deformation includes the maximum deformation amount, deformation speed and deformation mode. The specific steps are as follows: Determine whether the maximum deformation amount input is a negative value, and if the maximum deformation amount is a negative value, stop the calculation; Determine whether the total length of the input bumper is a positive value, and if the total length of the bumper is a non-positive value, stop the calculation; Verify whether the maximum deformation exceeds the total length of the bumper, and stop the calculation if the maximum deformation is greater than the total length of the bumper; After all data verification checks are passed, the maximum deformation is used as the numerator and the total length of the bumper is used as the denominator to perform a division operation to obtain the deformation degree value of the bumper; Setting warning thresholds for deformation levels; According to the warning threshold of the deformation degree, the deformation degree value of the bumper is judged; If the deformation value is greater than the preset warning threshold, the current bumper deformation is recorded and a warning message is generated; If the deformation degree value is less than or equal to the preset warning threshold, the current deformation of the bumper is recorded and information is generated that the deformation degree is within the normal range.

[0031] In the embodiment of the present invention, it is necessary to record the deformation of the bumper during the collision process, and the deformation includes the maximum deformation, deformation speed and deformation mode. The deformation speed refers to the change in the degree of deformation per unit time, and the deformation mode refers to the morphological change of the material or structure when subjected to external force, including axial deformation, tangential deformation, etc., and the degree of deformation needs to be calculated based on the maximum deformation, and the degree of deformation is equal to the ratio of the maximum deformation to the total length of the bumper. At the same time, it is also necessary to record the energy absorption information of the bumper during the collision process, and the energy absorption information includes the total absorbed energy and the energy absorption rate. The total absorbed energy refers to the total energy absorbed by the bumper structure during the entire collision process, and the energy absorption rate refers to the energy absorbed by the bumper structure per unit time. The energy absorption rate needs to be calculated based on the total absorbed energy, and the energy absorption rate is equal to the ratio of the total absorbed energy to the total collision energy.

[0032] like Figure 3 As shown, as a preferred embodiment of the present invention, the step of preliminarily determining the curvature radius range of the automobile bumper based on the collision simulation result specifically includes: S401, training a regression model based on historical collision data, wherein the independent variable of the regression model is the radius of curvature, and the dependent variables are the deformation speed, the deformation degree, the energy absorption rate and the energy absorption rate; S402, grouping the collision simulation results according to the curvature radius, and performing variance analysis, and determining the curvature radius range according to the variance analysis results.

[0033] Specifically, the collision simulation results are grouped according to the curvature radius, and variance analysis is performed. The curvature radius range is determined through the variance analysis results. The specific steps are as follows: Extract deformation degree data from collision simulation results; Group the collision simulation results according to the curvature radius to obtain a curvature radius array; Convert the curvature radius array into a two-dimensional structure to obtain the curvature radius; The radius of curvature is used as the independent variable and the deformation degree data is used as the dependent variable, which are input into the linear regression model for training; The linear regression model uses the least squares method to find the best fitting line to minimize the sum of square errors between the predicted value and the true value of the deformation degree data; The deformation degree data are grouped according to the unique value of the curvature radius, each group corresponds to a specific curvature radius, and each group contains all deformation degree data under the curvature radius; Calculate the mean and variance of the deformation degree data in each group, obtain the inter-group variance and the intra-group variance based on the mean and variance of the deformation degree data in each group, and then calculate the F statistic by the ratio of the inter-group variance to the intra-group variance, and further obtain the P value through the F statistic; Judge the P value according to the significance level; If the P value is less than the significance level, the influence of different curvature radii on the deformation degree data is judged to be significant, and the curvature radius is regarded as an effective factor affecting the deformation degree data; Then, the minimum and maximum values ​​in the current curvature radius data set are taken as the optimal curvature radius range; If the P value is greater than or equal to the significance level, it is determined that the influence of different curvature radii on the deformation data is not significant and a null value is returned.

[0034] Furthermore, the linear regression model uses the least squares method to find the best fitting line to minimize the sum of square errors between the predicted value and the true value of the deformation degree data. The specific steps are as follows: Determine whether the lengths of the curvature radius array and the deformation degree data group are consistent. If the lengths are inconsistent, stop the calculation. Convert the curvature radius and deformation degree data into NumPy arrays; Calculate the mean of the curvature radius array and the mean of the deformation degree data; Based on the curvature radius, the mean of the curvature radius array, the deformation degree data and the mean of the deformation degree data, the covariance between the curvature radius and the deformation degree data is calculated; The variance of the curvature radius is calculated by the curvature radius and the mean of the curvature radius array; Divide the covariance between the radius of curvature and the degree of deformation data by the variance of the radius of curvature to obtain the average change in the degree of deformation; Based on the average change in deformation degree, the mean of the curvature radius array and the mean of the deformation degree data, the theoretical value of the deformation degree is calculated; Based on the average change of deformation degree, the radius of curvature and the theoretical value of deformation degree, the predicted value of deformation degree data is calculated using the fitting straight line equation; The residual value of the deformation degree data is obtained by subtracting the predicted value of the deformation degree data from the actual deformation degree data; The residual value of each deformation degree data is squared and then summed to obtain the error square sum of the deformation degree data; The sum of square errors of deformation degree data is minimized by the least square method; The fitting straight line is drawn based on the sum of square errors of the deformation degree data.

[0035] In the embodiment of the present invention, in order to determine the appropriate curvature radius range, it is necessary to train a regression model in advance based on historical collision data, the independent variable of the regression model is the curvature radius, and the dependent variables are the deformation speed, deformation degree, energy absorption rate and energy absorption rate, so as to automatically analyze the deformation and energy absorption information of the bumper under different curvature radii. Then the collision simulation results are grouped according to the curvature radius, and variance analysis is performed. Through the variance analysis results, it is determined whether there is a significant difference in the collision performance of the bumper under different curvature radii, and it is determined which curvature radii have better deformation and stronger energy absorption capacity of the bumper, as well as the specific relationship between these performances and the curvature radius, and the appropriate curvature radius range is determined.

[0036] like Figure 4 As shown, as a preferred embodiment of the present invention, the step of determining the measurement accuracy and measurement stability of the radar in the automobile bumper within the curvature radius range specifically includes: S501, recording the measurement values ​​of the radar sensor at different distances and angles, and recording the measurement values ​​under different driving scenarios and obstacles; S502, comparing the measured value with a corresponding standard value to obtain a measurement accuracy of the radar sensor at different curvature radii; S503, recording the measured values ​​of the radar sensor under different environmental conditions and analyzing the change trend of the measured values; recording the measured values ​​of the radar sensor during long-term operation to determine the drift and error accumulation; S504, obtaining the measurement stability of the radar sensor at different curvature radii according to the change trend, drift condition and error accumulation.

[0037] Specifically, the measurement value is compared with the corresponding standard value to obtain the measurement accuracy of the radar sensor at different curvature radii. The specific steps are as follows: Verify the measured value and the standard value, each measured value corresponds to a unique standard value; For each pair of measured value and standard value, the absolute value difference is calculated; All absolute value differences are counted in an absolute value difference array. The length of the absolute value difference array is the same as the length of the measured value or the standard value, and each element in the absolute value difference array corresponds to an error value of the measured value. Add all the elements in the absolute difference array and divide by the total number of elements to get the average error; Find the largest value from the standard value array as the maximum standard value; Divide the mean value of the error by the maximum standard value to obtain the error ratio; Based on the error ratio, the measurement accuracy is obtained through normalization calculation; The measurement accuracy needs to be between 0 and 1, and the higher the value, the more accurate the measurement result; If the measurement accuracy is close to 1, it means that the measurement result of the radar sensor is almost consistent with the standard; If the measurement accuracy is close to 0, it means that the measurement result of the radar sensor deviates greatly from the standard.

[0038] In the embodiment of the present invention, static measurement experiments and dynamic measurement experiments are carried out. In the static measurement experiment, the measurement values ​​of the radar sensor at different distances and angles are recorded, and in the dynamic measurement experiment, the measurement values ​​under different driving scenes and obstacles are recorded. Then all the measurement values ​​are compared with the corresponding standard values ​​to obtain the measurement accuracy of the radar sensor at different curvature radii. Here, statistical analysis methods (such as mean, variance, standard deviation, etc.) can be used to process the measurement data to determine the measurement accuracy. When evaluating the measurement stability, the measurement values ​​of the radar sensor under different environmental conditions (such as temperature, humidity, vibration, etc.) are recorded, and the change trend of the measurement values ​​is analyzed; the measurement values ​​of the radar sensor during long-term operation are recorded to determine the drift and error accumulation. Finally, the measurement stability of the radar sensor at different curvature radii is obtained based on the change trend, drift and error accumulation.

[0039] like Figure 5 As shown, as a preferred embodiment of the present invention, the step of determining the optimal curvature radius range specifically includes: S505, the measurement accuracy and stability of the radar under different curvature radii are displayed through trend graphs; S506, adding a standard curve for evaluating measurement accuracy and measurement stability to the trend graph, determining a curvature radius that meets the standard curve, and obtaining an optimal curvature radius range.

[0040] In the embodiment of the present invention, the trend curve of the radar's measurement accuracy and measurement stability under different curvature radii will be finally displayed through a trend chart, and then the evaluation standard curve of the measurement accuracy and measurement stability will be added to the trend chart, and the curvature radius that meets the evaluation standard curve will be determined. The optimal curvature radius range can be obtained, providing strong support for the design and manufacture of automobile bumpers.

[0041] like Figure 6 As shown, an embodiment of the present invention further provides a system for determining parameters of an automobile bumper, the system comprising: The simulation model building module 100 is used to build a three-dimensional simulation model of a car bumper with different curvature radii and a whole vehicle, and divide the three-dimensional simulation model into multiple units using a finite element analysis method to simulate stress distribution and deformation during a collision; A collision parameter configuration module 200, used to configure collision parameters, wherein the collision parameters include collision speed, collision angle and collision object; A collision simulation result module 300 is used to run simulation software, simulate the conditions of bumpers with different curvature radii during collision, and record collision simulation results, which include deformation conditions and energy absorption information of the bumper; The curvature radius range module 400 is used to preliminarily determine the curvature radius range of the vehicle bumper based on the collision simulation results; The optimal curvature radius module 500 is used to determine the measurement accuracy and measurement stability of the radar in the car bumper within the curvature radius range, and determine the optimal curvature radius range.

[0042] As a preferred embodiment of the present invention, the collision simulation result module 300 includes: A deformation recording unit, used to record the deformation of the bumper during a collision, wherein the deformation includes a maximum deformation amount, a deformation speed and a deformation mode; A deformation degree calculation unit, used for calculating the deformation degree according to the maximum deformation, where the deformation degree is equal to the ratio of the maximum deformation to the total length of the bumper; An energy absorption information unit, used to record the energy absorption information of the bumper during the collision, wherein the energy absorption information includes the total absorbed energy and the energy absorption rate; The energy absorption rate calculation unit is used to calculate the energy absorption rate according to the total absorbed energy, and the energy absorption rate is equal to the ratio of the total absorbed energy to the total collision energy.

[0043] As a preferred embodiment of the present invention, the curvature radius range module 400 includes: A regression model training unit, used for training a regression model based on historical collision data, wherein the independent variable of the regression model is the radius of curvature, and the dependent variables are the deformation speed, deformation degree, energy absorption rate and energy absorption rate; The variance analysis unit is used to group the collision simulation results according to the curvature radius and perform variance analysis, and determine the curvature radius range through the variance analysis results.

[0044] As a preferred embodiment of the present invention, the optimal curvature radius module 500 includes: A first measurement value recording unit, used to record the measurement values ​​of the radar sensor at different distances and angles, and to record the measurement values ​​under different driving scenarios and obstacles; A measurement accuracy determination unit, used to compare the measurement value with a corresponding standard value to obtain the measurement accuracy of the radar sensor at different curvature radii; The second measurement value recording unit is used to record the measurement values ​​of the radar sensor under different environmental conditions and analyze the change trend of the measurement values; record the measurement values ​​of the radar sensor during long-term operation, determine the drift and error accumulation; The measurement stability determination unit is used to obtain the measurement stability of the radar sensor at different curvature radii according to the change trend, drift situation and error accumulation.

[0045] As a preferred embodiment of the present invention, the optimal curvature radius module 500 further includes: A trend graph display unit is used to display the measurement accuracy and stability of the radar under different curvature radii through trend graphs; The optimal curvature radius unit is used to add an evaluation standard curve of measurement accuracy and measurement stability to the trend chart, determine the curvature radius that meets the evaluation standard curve, and obtain the optimal curvature radius range.

[0046] The above only describes in detail the preferred embodiments of the present invention, which is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0047] It should be understood that, although each step in the flow chart of each embodiment of the present invention is shown in sequence according to the indication of the arrow, these steps are not necessarily performed in sequence according to the order indicated by the arrow. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be performed in other orders. Moreover, at least a portion of the steps in each embodiment may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a portion of other steps or sub-steps or stages of other steps.

[0048] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0049] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the disclosure in the specification and examples. This application is intended to cover any variations, uses or adaptations of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the claims.

Claims

1. A method for determining parameters of a vehicle bumper, characterized in that: The method comprises the following steps: Constructing three-dimensional simulation models of automobile bumpers and the entire vehicle with different curvature radii, and dividing the three-dimensional simulation models into multiple units using finite element analysis to simulate stress distribution and deformation during a collision; Configure collision parameters, including collision speed, collision angle and collision object; Run the simulation software to simulate the collision of bumpers with different curvature radii and record the collision simulation results, which include the deformation of the bumper and the energy absorption information; Preliminarily determine the curvature radius range of the car bumper based on the collision simulation results; Determine the measurement accuracy and stability of the radar in the car bumper within the curvature radius range, and determine the optimal curvature radius range; The step of recording the collision simulation results specifically includes: Recording the deformation of the bumper during the collision, wherein the deformation includes the maximum deformation amount, deformation speed and deformation mode; The deformation degree is calculated based on the maximum deformation, and the deformation degree is equal to the ratio of the maximum deformation to the total length of the bumper; Recording energy absorption information of the bumper during a collision, wherein the energy absorption information includes total absorbed energy and energy absorption rate; The energy absorption rate is calculated based on the total absorbed energy, and the energy absorption rate is equal to the ratio of the total absorbed energy to the total collision energy.

2. The method for determining automobile bumper parameters according to claim 1, characterized in that: Record the deformation of the bumper during the collision, including the maximum deformation, deformation speed and deformation mode. The specific steps are as follows: Determine whether the maximum deformation amount input is a negative value, and if the maximum deformation amount is a negative value, stop the calculation; Determine whether the total length of the input bumper is a positive value, and if the total length of the bumper is a non-positive value, stop the calculation; Verify whether the maximum deformation exceeds the total length of the bumper, and stop the calculation if the maximum deformation is greater than the total length of the bumper; After all data verification checks are passed, the maximum deformation is used as the numerator and the total length of the bumper is used as the denominator to perform a division operation to obtain the deformation degree value of the bumper; Setting warning thresholds for deformation levels; According to the warning threshold of the deformation degree, the deformation degree value of the bumper is judged; If the deformation value is greater than the preset warning threshold, the current bumper deformation is recorded and a warning message is generated; If the deformation degree value is less than or equal to the preset warning threshold, the current deformation of the bumper is recorded and information is generated that the deformation degree is within the normal range.

3. The method for determining automobile bumper parameters according to claim 2, characterized in that: The step of preliminarily determining the curvature radius range of the automobile bumper based on the collision simulation result specifically includes: The regression model is trained based on historical collision data. The independent variable of the regression model is the radius of curvature, and the dependent variables are deformation speed, deformation degree, energy absorption rate and energy absorption rate. The collision simulation results are grouped according to the curvature radius and variance analysis is performed. The curvature radius range is determined based on the variance analysis results.

4. The method for determining automobile bumper parameters according to claim 3, characterized in that: The collision simulation results are grouped according to the curvature radius and variance analysis is performed. The curvature radius range is determined through the variance analysis results. The specific steps are as follows: Extract deformation degree data from collision simulation results; Group the collision simulation results according to the curvature radius to obtain a curvature radius array; Convert the curvature radius array into a two-dimensional structure to obtain the curvature radius; The radius of curvature is used as the independent variable and the deformation degree data is used as the dependent variable, which are input into the linear regression model for training; The linear regression model uses the least squares method to find the best fitting line to minimize the sum of square errors between the predicted value and the true value of the deformation degree data; The deformation degree data are grouped according to the unique value of the curvature radius, each group corresponds to a specific curvature radius, and each group contains all deformation degree data under the curvature radius; Calculate the mean and variance of the deformation degree data in each group, obtain the inter-group variance and the intra-group variance based on the mean and variance of the deformation degree data in each group, and then calculate the F statistic by the ratio of the inter-group variance to the intra-group variance, and further obtain the P value through the F statistic; Judge the P value according to the significance level; If the P value is less than the significance level, the influence of different curvature radii on the deformation degree data is judged to be significant, and the curvature radius is regarded as an effective factor affecting the deformation degree data; Then, the minimum and maximum values ​​in the current curvature radius data set are taken as the optimal curvature radius range; If the P value is greater than or equal to the significance level, it is determined that the influence of different curvature radii on the deformation data is not significant and a null value is returned.

5. The method for determining parameters of a vehicle bumper according to claim 4, characterized in that: The linear regression model uses the least squares method to find the best fitting line to minimize the sum of square errors between the predicted value and the true value of the deformation degree data. The specific steps are as follows: Determine whether the lengths of the curvature radius array and the deformation degree data group are consistent. If the lengths are inconsistent, stop the calculation. Convert the curvature radius and deformation degree data into NumPy arrays; Calculate the mean of the curvature radius array and the mean of the deformation degree data; Based on the curvature radius, the mean of the curvature radius array, the deformation degree data and the mean of the deformation degree data, the covariance between the curvature radius and the deformation degree data is calculated; The variance of the curvature radius is calculated by the curvature radius and the mean of the curvature radius array; Divide the covariance between the radius of curvature and the degree of deformation data by the variance of the radius of curvature to obtain the average change in the degree of deformation; Based on the average change in deformation degree, the mean of the curvature radius array and the mean of the deformation degree data, the theoretical value of the deformation degree is calculated; Based on the average change of deformation degree, the radius of curvature and the theoretical value of deformation degree, the predicted value of deformation degree data is calculated using the fitting straight line equation; The residual value of the deformation degree data is obtained by subtracting the predicted value of the deformation degree data from the actual deformation degree data; The residual value of each deformation degree data is squared and then summed to obtain the error square sum of the deformation degree data; The sum of square errors of deformation degree data is minimized by the least square method; The fitting straight line is drawn based on the sum of square errors of the deformation degree data.

6. The method for determining parameters of a vehicle bumper according to claim 5, characterized in that: The step of determining the measurement accuracy and measurement stability of the radar in the automobile bumper within the curvature radius range specifically includes: Record the radar sensor's measurements at different distances and angles, and record the measurements under different driving scenarios and obstacles; Comparing the measured value with the corresponding standard value to obtain the measurement accuracy of the radar sensor at different curvature radii; Record the measured values ​​of radar sensors under different environmental conditions and analyze the changing trends of the measured values; record the measured values ​​of radar sensors during long-term operation to determine drift and error accumulation; The measurement stability of the radar sensor at different curvature radii is obtained based on the change trend, drift and error accumulation.

7. The method for determining automobile bumper parameters according to claim 6, characterized in that: The measured value is compared with the corresponding standard value to obtain the measurement accuracy of the radar sensor at different curvature radii. The specific steps are as follows: Verify the measured value and the standard value, each measured value corresponds to a unique standard value; For each pair of measured value and standard value, the absolute value difference is calculated; All absolute value differences are counted in an absolute value difference array. The length of the absolute value difference array is the same as the length of the measured value or the standard value, and each element in the absolute value difference array corresponds to an error value of the measured value. Add all the elements in the absolute difference array and divide by the total number of elements to get the average error; Find the largest value from the standard value array as the maximum standard value; Divide the mean value of the error by the maximum standard value to obtain the error ratio; Based on the error ratio, the measurement accuracy is obtained through normalization calculation.

8. The method for determining automobile bumper parameters according to claim 7, characterized in that: The step of determining the optimal curvature radius range specifically includes: The measurement accuracy and stability of the radar under different curvature radii are displayed through trend graphs; An evaluation standard curve for measurement accuracy and measurement stability is added to the trend chart, and the curvature radius that meets the evaluation standard curve is determined to obtain the optimal curvature radius range.

9. A system for determining parameters of a car bumper, characterized in that: The system applies the method for determining parameters of a vehicle bumper as described in any one of claims 1 to 8, and the system comprises: A simulation model building module is used to build a three-dimensional simulation model of a car bumper with different curvature radii and a whole vehicle, and divide the three-dimensional simulation model into multiple units using a finite element analysis method to simulate stress distribution and deformation during a collision; A collision parameter configuration module, used to configure collision parameters, wherein the collision parameters include collision speed, collision angle and collision object; The collision simulation result module is used to run the simulation software, simulate the bumpers with different curvature radii during the collision process, and record the collision simulation results, which include the deformation of the bumper and the energy absorption information; The curvature radius range module is used to preliminarily determine the curvature radius range of the car bumper based on the collision simulation results; The optimal curvature radius module is used to determine the measurement accuracy and measurement stability of the radar in the car bumper within the curvature radius range and determine the optimal curvature radius range.

10. The automobile bumper parameter determination system according to claim 9, characterized in that: The collision simulation result module includes: A deformation recording unit, used to record the deformation of the bumper during a collision, wherein the deformation includes a maximum deformation amount, a deformation speed and a deformation mode; A deformation degree calculation unit, used for calculating the deformation degree according to the maximum deformation, where the deformation degree is equal to the ratio of the maximum deformation to the total length of the bumper; An energy absorption information unit, used to record the energy absorption information of the bumper during the collision, wherein the energy absorption information includes the total absorbed energy and the energy absorption rate; The energy absorption rate calculation unit is used to calculate the energy absorption rate according to the total absorbed energy, and the energy absorption rate is equal to the ratio of the total absorbed energy to the total collision energy.

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