Deformation safety threshold analysis method for brake calipers

Abstract

The invention relates to the technical field of brake calipers, and discloses a brake caliper deformation safety threshold analysis method comprising the following steps: carrying out 3D scanning reverse modeling on a brake caliper to obtain a reverse modeling model, and obtaining the initial characteristics of the brake caliper; performing finite element analysis on the reverse modeling model to obtain feature points and screen out key nodes; finding initial key nodes corresponding to the key nodes in the initial feature points; the displacement distance between the key node and the initial key node of the brake caliper is obtained through calculation; according to the method, the key nodes are found through Pearson's correlation coefficient calculation, and the deformation distance of the key nodes is used as an evaluation standard of the safety performance of the brake calipers, so that structural points related to the safety performance of the brake calipers can be interpreted, deformation feature points are reduced, and the safety performance of the brake calipers is improved. Safety performance analysis steps of the brake calipers are reduced, and any brake calipers can be conveniently analyzed.

Description

Technical Field

[0001] The present invention relates to the technical field of brake calipers, and specifically to a method for analyzing the deformation safety threshold of a brake caliper. Background Technique

[0002] With the rapid development of the domestic automobile industry, consumers' requirements for the NVH performance of automobiles are also constantly increasing. The vibration and interior noise performance of automobiles have attracted more and more attention from major automobile enterprises. During the continuous braking process of the vehicle, the caliper will deform, resulting in uneven contact between the caliper and the brake disc, which will affect the fluctuation of the braking torque of the brake. At this time, the braking will be abnormal, resulting in severe vibrations of the steering wheel, brake pedal, vehicle floor, and seat, etc., seriously affecting the safety of the vehicle and the comfort of the passengers inside the vehicle.

[0003] At present, there are a wide variety of brake calipers on the market, and it is difficult to give a unified deformation safety threshold for brake calipers. However, considering the safety of vehicle operation, the brake caliper should be replaced before it reaches the deformation safety threshold to prevent safety accidents. Therefore, a method for analyzing the deformation safety threshold of a brake caliper is proposed, which can analyze and give the corresponding deformation safety threshold for different brake calipers. Summary of the Invention

[0004] (I) Technical Problems to be Solved The purpose of the present invention is to solve the problem of finding the deformation safety threshold of a brake caliper, and to replace the brake caliper before it reaches the deformation safety threshold to prevent safety accidents, and to propose a method for analyzing the deformation safety threshold of a brake caliper.

[0005] (II) Technical Solutions The technical solutions of the present invention for solving the above technical problems are as follows: A method for analyzing the deformation safety threshold of a brake caliper includes the following steps: S1: Perform 3D scanning and reverse modeling on the brake caliper B to obtain a reverse modeling model and obtain the initial feature points of the brake caliper B ; S2: Perform finite element analysis on the reverse modeling model to obtain deformation feature points; S3: Screen out the key nodes from the deformation feature points ; S4: Find out the initial key nodes corresponding to the key nodes in the initial feature points ; S5: Calculate and obtain the key nodes and the initial key nodes of the brake caliper B ​ The displacement distance between ; S6: Determine the maximum displacement distance in S5 and use the maximum displacement distance as the safe deformation distance .

[0006] Based on the above technical solution, the present invention can also be improved as follows.

[0007] Preferably, S2 includes the following steps: First, import the reverse modeling model into the finite element analysis software, generate a finite element model, set constraints and loads, and set the solution parameters to obtain the stress and strain of the model, identify and extract deformation feature points.

[0008] Preferably, S3 includes the following steps: Obtain the correlation coefficients between the deformation feature points and the braking safety performance of the brake caliper B, and use the deformation feature points with the correlation coefficients of the braking safety performance greater than the control value of the correlation coefficients of the braking safety performance as the key nodes.

[0009] Preferably, the process of obtaining the correlation coefficients between the deformation feature points and the braking safety performance of the brake caliper B is as follows: Obtain the brake performance index matrix of the brake caliper , for the deformation feature points and the brake performance index matrix of the brake caliper perform preprocessing to remove the outliers therein, and then perform normalization processing to obtain the preprocessed deformation feature points , the brake performance index matrix of the brake caliper , calculate the correlation between the deformation feature points and the brake performance index matrix of the brake caliper based on the Pearson correlation coefficient, and the calculation expression is: In the formula, represents the i-th , represents the mean value of represents the f-th , represents the mean value of is the e-th first correlation parameter, is the f-th second correlation parameter, is the mean value of the first correlation parameter, is the mean value of the second relevant parameter, and r represents the deformation feature point and the braking performance index matrix of the brake caliper The correlation coefficient between .

[0010] Preferably, the control value of the correlation coefficient of the braking safety performance relationship is obtained as follows: The deformation feature point and the braking performance index matrix of the brake caliper The correlation coefficient between is screened out, and the mean value of the screened correlation coefficient r is obtained and the mode , and the control value of the correlation coefficient of the braking safety performance relationship is generated through weighting , and the weighting formula is as follows: In the formula, and respectively represent taking the mean value weight coefficient, mode weight coefficient.

[0011] Preferably, the takes a value of 0.9.

[0012] Preferably, the and are obtained as follows: The entropy value method is used to obtain and : First, the mean value weight index and the mode weight index are obtained. Each index has observation values, and each index is standardized. The standardization formula is: or In the formula, represents the standardized value of the i-th observation value on the j-th index, represents the original data, and represent the maximum and minimum values of the j-th index; Then, the proportion of each observation value on the corresponding index is calculated. The formula is: Subsequently, the entropy value of each index is calculated according to the proportion. The formula is: where k is a constant, usually taking a value of Then calculate the coefficient of variation, and the formula is: Finally, calculate the weight coefficient, and the formula is: where is the number of indicators, that is, the value is 2.

[0013] Preferably, the S4 includes the following steps: During 3D scanning reverse modeling of the brake caliper B, mark the initial feature points of the brake caliper B so that each initial feature point has a unique identifier. After screening out the key nodes according to the position, deformation characteristics and set structure of the key nodes automatically find the corresponding initial key nodes in the initial feature points using feature matching technology. .

[0014] (III) Beneficial effects Compared with the prior art, the technical solution of the present application has the following beneficial technical effects: The present invention finds the key nodes by calculating the Pearson correlation coefficient , and uses the deformation distance of the key nodes as the evaluation criterion for the safety performance of the brake caliper, which can not only interpret the structural points related to the safety performance of the brake caliper, but also reduce the deformation feature points, reduce the analysis steps of the safety performance of the brake caliper, and facilitate the analysis of any brake caliper. Specific embodiments

[0015] The following will combine the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0016] A method for analyzing the deformation safety threshold of a brake caliper includes the following steps: S1: Perform 3D scanning reverse modeling on the brake caliper B to obtain a reverse modeling model and obtain the initial feature points of the brake caliper B ; S2: Perform finite element analysis on the reverse modeling model to obtain deformation feature points; S3: Select key nodes from deformation feature points; ; S4: Find the initial key nodes corresponding to the key nodes in the initial feature points; ; S5: Calculate the displacement distance between the obtained key nodes and the initial key nodes of the brake caliper B ; ; S6: Determine the maximum displacement distance in S5 and use the maximum displacement distance as the safe deformation distance ; It is also possible to obtain m brake calipers after the vehicle has traveled x kilometers, perform 3D scanning reverse modeling on the m brake calipers, obtain the actual displacement distance, then analyze the braking function of the m brake calipers to obtain the actual maximum safe displacement distance, compare it with the safe deformation distance to verify the accuracy of the safe deformation distance .

[0017] The above S2 includes the following steps: First, import the reverse modeling model into the finite element analysis software, generate a finite element model, set constraints and loads, and set the solution parameters to obtain the stress and strain of the model, identify and extract deformation feature points; Specifically, according to the analysis requirements, apply corresponding loads such as force, pressure, temperature, etc. to the finite element model, set the boundary conditions of the model such as fixed constraints, position constraints, etc. to ensure the stability and accuracy of the model during the analysis process, select a suitable solver, and set the solution parameters such as the number of iterations, convergence criteria, etc., then start the solver to solve the finite element model to obtain analysis results such as the stress and strain of the model, and finally view the solution results in the finite element analysis software, and identify and extract the deformation feature points according to the analysis results.

[0018] The above S3 includes the following steps: Obtain the correlation coefficient between the deformation feature points and the braking safety performance of the brake caliper B, and use the deformation feature points with the correlation coefficient of the braking safety performance greater than the control value of the correlation coefficient of the braking safety performance as the key nodes.

[0019] The above-mentioned obtaining The correlation coefficient process between the deformation feature points and the braking safety performance of the brake caliper B is as follows: Obtain the braking performance index matrix of the brake caliper , for the deformation feature points and the braking performance index matrix of the brake caliper perform preprocessing to remove the outliers, and then perform normalization processing to obtain the preprocessed deformation feature points , the braking performance index matrix of the brake caliper , calculate the correlation between the deformation feature points and the braking performance index matrix of the brake caliper using the Pearson correlation coefficient. The calculation formula is: In the formula, represents the i-th , represents the mean value of represents the f-th , represents the mean value of is the e-th first correlation parameter, is the f-th second correlation parameter, is the mean value of the first correlation parameter, is the mean value of the second correlation parameter, r represents the correlation coefficient between the deformation feature points and the braking performance index matrix of the brake caliper . .

[0020] The acquisition process of the correlation coefficient control value of the braking safety performance relationship is as follows: Filter out the correlation coefficient between the deformation feature points and the braking performance index matrix of the brake caliper . Calculate the mean value and the mode of the filtered correlation coefficient r, and generate the correlation coefficient control value of the braking safety performance relationship through weighting. The weighting formula is as follows: In the formula, In the formula, and respectively represent the mean value weight coefficient, and the mode weight coefficient.

[0021] The value is 0.9.

[0022] The and acquisition process is as follows: Use the entropy method to obtain and : First, obtain the mean weight index and the mode weight index , each index has observations, and standardize each index. The standardization formula is: or In the formula, represents the standardized value of the i-th observation on the j-th index, represents the original data, and represent the maximum and minimum values of the j-th index; Then calculate the proportion of each observation on the corresponding index. The formula is: ; Subsequently, calculate the entropy value of each index according to the proportion. The formula is: In the formula, k is a constant, usually taking the value of ; Then calculate the coefficient of variation. The formula is: ; Finally, calculate the weight coefficient. The formula is: In the formula, is the number of indices, that is, the value is 2.

[0023] S4 includes the following steps: During 3D scanning reverse modeling, mark the initial feature points of the brake caliper B, so that each initial feature point has a unique identifier. After screening out the key nodes , according to the position, deformation characteristics and set structure of the key nodes , use feature matching technology to automatically find the corresponding initial key nodes in the initial feature points .

[0024] It should be noted that, in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0025] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for analyzing the deformation safety threshold of a brake caliper, characterized in that: The steps include: S1: Perform 3D scanning and reverse modeling on the brake caliper B to obtain a reverse modeling model and obtain the initial feature points of the brake caliper B ; S2: Perform finite element analysis on the reverse modeling model to obtain deformation feature points; S3: From Select key nodes from the deformation feature points ; S4: Initial feature points Corresponding key nodes The initial key node Find out; S5: Calculate and obtain key nodes Initial key node with brake caliper B The displacement distance between ; S6: Determine the maximum displacement distance in S5 And the maximum displacement distance As a safe deformation distance .

2. The method for analyzing the deformation safety threshold of a brake caliper according to claim 1, characterized in that: The S2 comprises the following steps: First, the reverse modeling model is imported into the finite element analysis software to generate the finite element model, set the constraints and loads, and set the solution parameters to obtain the stress and strain of the model, identify and extract deformation feature points.

3. The method for analyzing the deformation safety threshold of a brake caliper according to claim 1, characterized in that: The S3 comprises the following steps: Get The braking safety performance correlation coefficient of the deformation feature point and the brake caliper B is set to be greater than the braking safety performance correlation coefficient control value The deformation feature points are taken as key nodes.

4. The method for analyzing the deformation safety threshold of a brake caliper according to claim 3, characterized in that: The acquisition The correlation coefficient process between the deformation characteristic points and the braking safety performance of the brake caliper B is as follows: Get the brake caliper brake performance index matrix ,right Deformation feature points and brake caliper brake performance index matrix Preprocessing is performed to remove outliers, and then normalization is performed to obtain preprocessed deformation feature points. , Brake caliper brake performance index matrix , calculate deformation feature points based on Pearson correlation coefficient Braking performance index matrix with brake calipers The correlation between them is calculated as: In the formula, Indicates the i-th , express The mean of Indicates the fth , express The mean of is the e-th first related parameter, is the fth second related parameter, is the mean of the first correlation parameter, is the mean value of the second related parameter, r represents the deformation feature point and brake caliper brake performance index matrix The correlation coefficient between .

5. The method for analyzing the deformation safety threshold of a brake caliper according to claim 3, characterized in that: The braking safety performance relationship correlation coefficient control value The acquisition process is as follows: Deform feature points and brake caliper brake performance index matrix The correlation coefficient between The selected correlation coefficient r is averaged and majority , generate the braking safety performance correlation coefficient control value through weighting , the weighted formula is as follows: In the formula, and Respectively represent the mean Weight coefficient, mode Weight coefficient.

6. The method for analyzing the deformation safety threshold of a brake caliper according to claim 5, characterized in that: Said The value of is 0.

9.

7. The method for analyzing the deformation safety threshold of a brake caliper according to claim 5, characterized in that: Said and The acquisition process is as follows: Using entropy method to obtain and : First get the mean Weight Index and majority Weight Index , each indicator has observations, and each indicator is standardized. The standardization formula is: or In the formula, represents the standardized value of the i-th observation on the j-th index, Represents the original data, and Indicates the maximum and minimum values ​​of the jth indicator; Then calculate the proportion of each observation value in the corresponding indicator, the formula is: ； Then the entropy value of each indicator is calculated according to the proportion, the formula is: In the formula, k is a constant, usually taken as ; Then calculate the coefficient of difference, the formula is: ； Finally, the weight coefficient is calculated as follows: In the formula, is the number of indicators, that is, the value is 2.

8. The method for analyzing the deformation safety threshold of a brake caliper according to claim 1, characterized in that: The S4 comprises the following steps: During 3D scanning reverse modeling, the initial feature points of the brake caliper B are Mark so that each initial feature point Each node has a unique identifier. Then, according to the key nodes The position and deformation features and set structure of the initial feature points are automatically matched using feature matching technology. Find the corresponding initial key node in .

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