Dynamic stiffness simulation verification method, device and equipment of suspension attachment point and medium

Abstract

The invention provides a dynamic stiffness simulation verification method and device for a suspension attachment point, equipment and a medium, and the method comprises the steps: obtaining a target attachment point of a suspension support; respectively simulating and testing the dynamic stiffness of the target attachment point in the preset direction to obtain a simulated dynamic stiffness curve and an actually measured dynamic stiffness curve; calculating according to the simulated dynamic stiffness curve and the actually measured dynamic stiffness curve, and determining an amplitude difference and a phase difference; calculating according to the amplitude and the phase difference, and determining combined measurement; and comparing the combined measurement with preset precision, and determining a simulation verification result of the dynamic stiffness in the preset direction. Therefore, the difference between the dynamic stiffness simulation and the test of the suspension attachment point is balanced through the combination measurement, so that the accuracy of the dynamic stiffness simulation is verified, and the accuracy and the reliability of the simulation are improved.

Description

Technical Field

[0001] The present application relates to the technical field of vehicle dynamic stiffness simulation, and particularly to a method, device, equipment and medium for dynamically simulating and verifying the stiffness of a mounting attachment point. Background Art

[0002] In the field of vehicle engineering, the mounting system is a complex vibration system, which usually consists of components such as mounts, mounting brackets, and mounting bushings. Its main function is to isolate and reduce the vibration generated by key components such as the powertrain from affecting the vehicle body and passengers, and improve the NVH (Noise, Vibration, and Harshness) performance of the whole vehicle. The design and optimization of the mounting system are crucial for ensuring the comfort and stability of the vehicle. The mounting attachment point is a key part of the mounting system. It usually refers to the connection point between the mounting element and the surrounding structure (such as the mounting bracket). These attachment points play an important role in transmitting and bearing various forces and vibrations from the powertrain and the vehicle body, and their design has an important impact on the performance of the mounting system. In the related art, in order to ensure the performance of the mounting system, the dynamic stiffness of the mounting attachment point is simulated during the design stage, so as to improve the reliability of the mounting system design.

[0003] However, the dynamic stiffness of the mounting attachment point is not only affected by the characteristics of the mounting element itself, but also highly dependent on the stiffness and strength distribution of the surrounding structure, including the design of the mounting point, the interaction between adjacent components, and the dynamic response of the overall structure. During the actual R & D process, it is difficult to accurately predict the true value of the attachment point dynamic stiffness solely by simulation means. There will be a certain deviation between the simulated value obtained from the simulation analysis and the true value measured in actual tests, which cannot guarantee the accuracy of the dynamic stiffness simulation, resulting in low accuracy and reliability of the simulation. Summary of the Invention

[0004] To provide a basic understanding of some aspects of the disclosed embodiments, a simple summary is given below. This summary is not a comprehensive review, nor is it intended to identify key / important elements or delineate the scope of protection of these embodiments. Instead, it serves as a preamble to the following detailed description.

[0005] In view of the above-mentioned disadvantages of the prior art, the present application discloses a method, device, equipment and medium for dynamically simulating and verifying the stiffness of a mounting attachment point to solve the above technical problem of how to verify the simulation accuracy of the dynamic stiffness of the mounting attachment point.

[0006] In a first aspect, the present application provides a method for simulating and verifying the dynamic stiffness of a suspension attachment point. The method includes: obtaining a target attachment point of a suspension bracket; respectively simulating and testing the dynamic stiffness of the target attachment point in a preset direction to obtain a simulated dynamic stiffness curve and a measured dynamic stiffness curve; calculating according to the simulated dynamic stiffness curve and the measured dynamic stiffness curve to determine an amplitude difference and a phase difference; calculating according to the amplitude and the phase difference to determine a combined metric; comparing the combined metric with a preset accuracy to determine the simulation verification result of the dynamic stiffness in the preset direction.

[0007] In an embodiment of the present application, the step of respectively simulating and testing the dynamic stiffness of the target attachment point in a preset direction to obtain a simulated dynamic stiffness curve and a measured dynamic stiffness curve includes: constructing a finite element model of the suspension bracket and using the target attachment point as a response point of the finite element model; applying a load in the preset direction to the response point of the finite element model according to a preset mapping relationship to obtain the simulated dynamic stiffness curve corresponding to the preset direction. The preset mapping relationship is a mapping relationship between frequency points and forces, and the load is characterized by a force; performing a dynamic stiffness test on the target attachment point in the preset direction based on the preset mapping relationship to obtain the measured dynamic stiffness curve corresponding to the preset direction.

[0008] In an embodiment of the present application, the step of applying a load in the preset direction to the response point of the finite element model according to a preset mapping relationship includes: determining the force applied at each frequency point based on the preset mapping relationship; determining the force applied at each frequency point based on the preset mapping relationship; using the force applied at each frequency point as the magnitude of the load of the finite element model and applying it to the response point of the finite element model in the preset direction to simulate preset response data of the target attachment point changing with frequency under the action of the force. The preset response data includes any one of acceleration, displacement, and circular frequency.

[0009] In an embodiment of the present application, the step of calculating according to the simulated dynamic stiffness curve and the measured dynamic stiffness curve to determine an amplitude difference and a phase difference includes: respectively converting the simulated dynamic stiffness curve and the measured dynamic stiffness curve into discrete signals to obtain a simulated signal and a measured signal; calculating the means of the simulated signal and the measured signal respectively to obtain a first mean and a second mean; calculating according to the first mean and the second mean to determine the amplitude difference and the phase difference between the simulated signal and the measured signal.

[0010] In an embodiment of the present application, the step of calculating according to the amplitude and the phase difference to determine a combined metric includes: calculating the sum of squares between the amplitude and the phase difference to determine a target sum of squares; calculating according to a preset threshold and the target sum of squares to determine the combined metric.

[0011] In an embodiment of the present application, the comparison between the combined metric and the preset accuracy to determine the simulation verification result of the dynamic stiffness in the preset direction includes: comparing the combined metric with the preset accuracy corresponding to the preset direction, where the preset direction includes the horizontal axis direction, the vertical axis direction, and the vertical axis direction, and the preset direction and the preset accuracy correspond one by one; if the combined metric is greater than or equal to the preset accuracy, it is determined that the simulation verification result of the dynamic stiffness in the preset direction is qualified; if the combined metric is less than the preset accuracy, it is determined that the simulation verification result of the dynamic stiffness in the preset direction is unqualified, and the dynamic stiffness simulation of the target attachment point is corrected.

[0012] In an embodiment of the present application, obtaining the simulated dynamic stiffness curve and the measured dynamic stiffness curve includes: applying the load in the preset direction to the response point of the finite element model, and calculating the simulated response curve formed by the preset response data changing with frequency in the preset direction; applying a force to the target attachment point in the preset direction, and measuring the measured response curve formed by the preset response data changing with frequency in the preset direction; respectively calculating the source point admittance according to the simulated response curve and the measured response curve to obtain the simulated dynamic stiffness curve and the measured dynamic stiffness curve.

[0013] In a second aspect, the present application provides a dynamic stiffness simulation verification device for a suspension attachment point. The device includes: an acquisition module for acquiring a target attachment point of a suspension bracket; a simulation test module for respectively simulating and testing the dynamic stiffness of the target attachment point in a preset direction to obtain a simulated dynamic stiffness curve and a measured dynamic stiffness curve; a first calculation module for calculating according to the simulated dynamic stiffness curve and the measured dynamic stiffness curve to determine the amplitude difference and the phase difference; a second calculation module for calculating according to the amplitude and the phase difference to determine a combined metric; a comparison module for comparing the combined metric with a preset accuracy to determine the simulation verification result of the dynamic stiffness in the preset direction.

[0014] In a third aspect, the present application further provides an electronic device, including: a processor, a memory, and a communication bus; the communication bus is used to connect the processor and the memory; the processor is used to execute a computer program stored in the memory to implement the method as described in the above embodiment.

[0015] In a fourth aspect, the present application provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor of a computer, the computer is enabled to execute the method as described in the above embodiment.

[0016] Advantages of the present application: The present application provides a method, apparatus, device, and medium for simulating and verifying the dynamic stiffness of a suspension attachment point. By obtaining the target attachment point of the suspension bracket, simulating and testing the dynamic stiffness of the target attachment point in a preset direction, obtaining the simulated dynamic stiffness curve and the measured dynamic stiffness curve, then calculating the amplitude difference and phase difference between the simulated dynamic stiffness curve and the measured dynamic stiffness curve, calculating based on the amplitude and phase difference to determine the combined metric; comparing the combined metric with a preset accuracy to determine the simulation verification result of the dynamic stiffness in the preset direction. In this way, based on the simulated dynamic stiffness curve and the measured dynamic stiffness curve in the preset direction, a combined metric for measuring the difference between the dynamic stiffness simulation and the test is calculated to verify the accuracy of the simulation, improving the accuracy and reliability of the dynamic stiffness simulation, and helping to save the R & D time and later rectification cost of the suspension system.

[0017] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and do not limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts. In the drawings:

[0019] Figure 1 is a schematic diagram of a vibration isolation system structure shown in an exemplary embodiment of the present application;

[0020] Figure 2 is a flowchart of a method for simulating and verifying the dynamic stiffness of a suspension attachment point shown in an exemplary embodiment of the present application;

[0021] Figure 3 is a schematic diagram of a finite element model shown in an exemplary embodiment of the present application;

[0022] Figure 4 is a schematic diagram of a test for the dynamic stiffness of an attachment point shown in an exemplary embodiment of the present application;

[0023] Figure 5 is a schematic diagram of the comparison of the dynamic stiffness curve in the horizontal axis direction shown in an exemplary embodiment of the present application;

[0024] Figure 6 is a schematic diagram of the comparison of the dynamic stiffness curve in the vertical axis direction shown in an exemplary embodiment of the present application;

[0025] Figure 7It is a schematic diagram of the comparison of the dynamic stiffness curves in the vertical axis direction shown in an exemplary embodiment of the present application;

[0026] Figure 8 It is a schematic diagram of the overall process of dynamic stiffness simulation verification shown in an exemplary embodiment of the present application;

[0027] Figure 9 It is a schematic diagram of the overall architecture of dynamic stiffness simulation verification shown in an exemplary embodiment of the present application;

[0028] Figure 10 It is a block diagram of a device for dynamic stiffness simulation verification of a mount attachment point shown in an exemplary embodiment of the present application;

[0029] Figure 11 It is a schematic diagram of the structure of a computer system suitable for implementing the electronic device of the present application shown in an exemplary embodiment of the present application. Detailed implementation manners

[0030] The following will describe the implementation manners of the present application with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand the other advantages and effects of the present application from the content disclosed in this specification. The present application can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be understood that the preferred embodiments are only for explaining the present application, rather than for limiting the protection scope of the present application.

[0031] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present application in a schematic manner. Therefore, only the components related to the present application are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0032] In the following description, a large number of details are explored to provide a more thorough explanation of the embodiments of the present application. However, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present application difficult to understand.

[0033] The vehicle's suspension system connects key components such as the powertrain to the body or frame through elastic elements, providing necessary support and fixation. This support and fixation ensure the stability and reliability of components like the powertrain during vehicle operation, avoiding failures and safety hazards caused by component loosening or displacement. The stiffness of the suspension system and the dynamic stiffness at the attachment points are important indicators for evaluating the performance of the suspension system, which have significant impacts on aspects such as the vehicle's NVH performance, handling performance, and ride comfort. Among them, the stiffness of the suspension system refers to the external force required to produce a unit displacement at a certain position on an object in a specific direction, and its commonly used engineering unit is N / mm (Newton per millimeter). Stiffness determines the response characteristics of the system to external excitations. In a vehicle, the stiffness design of the suspension system needs to comprehensively consider factors such as the weight of the powertrain, vibration characteristics, and vehicle driving conditions. A reasonable stiffness design can effectively reduce the vibration and noise transmitted from the powertrain to the body and improve ride comfort. The dynamic stiffness at the attachment points of the suspension system is related to the stiffness. Dynamic stiffness is the manifestation of stiffness under dynamic loads. They jointly determine the performance of the suspension system. The magnitude of dynamic stiffness also affects the response characteristics and transmission characteristics of the suspension system to external excitations. Insufficient dynamic stiffness may cause large deformations and displacements of the suspension system under dynamic loads, thus affecting the vehicle's handling performance and ride comfort. Therefore, in the design and optimization process of the suspension system, the requirements of stiffness and dynamic stiffness need to be comprehensively considered, and the best performance can be achieved through reasonable parameter design and structural layout.

[0034] Please refer to Figure 1 , which shows a schematic diagram of a vibration isolation system illustrated in an exemplary embodiment of the present application. As Figure 1 shown, taking the vibration isolation system in the vehicle suspension system as an example, it at least includes brackets and mounts. The brackets are connection elements between the powertrain and the body. Generally, there is one bracket on each of the powertrain side and the body side. The powertrain side bracket, mount, and body side bracket form a vibration isolation system as the path for vibration transmission. Among them, the brackets have a certain stiffness, just like a hard spring. Therefore, the stiffness of the vibration isolation system is not only the stiffness of the mounts, but also depends on the stiffness of the two brackets. The total stiffness of these three in series is the stiffness of the vibration isolation system. As Figure 1 shown, the expression for calculating the stiffness of the vibration isolation system is as follows:

[0035]

[0036] Among them, in formula (1), K represents the stiffness of the vibration isolation system, K PT represents the stiffness of the active side of the mount, that is, the stiffness at the powertrain side bracket, K M represents the stiffness of the mount, K BIt represents the stiffness of the passive side of the mount, that is, the stiffness at the body side bracket. As can be seen from Equation (1), if the stiffnesses of both brackets are extremely hard, that is, their stiffness values tend to be theoretically infinite, then the stiffness of the vibration isolation system is mainly determined by the stiffness characteristics of the mount itself. However, when the stiffness of the bracket is relatively low, it may cause resonance of the local structure, which will exacerbate the generation of structure-borne noise and then transmit this noise into the vehicle interior space, having an adverse impact on the passenger's riding experience. In summary, in order to achieve good vibration isolation effect and ensure that the transmission of vibration and noise is significantly suppressed, the stiffness of the bracket must be designed to be much higher than that of the mount, meeting certain proportional requirements. This design principle is crucial for improving the vibration isolation effect. Therefore, when designing and optimizing the mount bracket and the mount system, it is particularly important to conduct accurate dynamic stiffness analysis on the mount bracket.

[0037] The dynamic stiffness analysis of the mount bracket targets the dynamic stiffness of the attachment point, that is, the input point inertance (IPI), which refers to the ratio of the excitation force to the displacement in the same position and the same direction, mainly considering the stiffness level of the local area of the attachment point within the frequency range of interest. Taking the Figure 1 vibration isolation system in it as an example, its performance is affected by the dynamic stiffness of the active side attachment point, the stiffness of the mount (mount element), and the dynamic stiffness of the passive side attachment point. Among them, the bushing stiffness is mainly designed according to the system performance requirements and is easy to adjust.

[0038] However, in practical applications, there are often significant differences between the expected values of the performance design of the mount system and the actual values obtained through experimental measurements. After analysis, it is found that the main root cause of the difference lies in the significant inconsistency between the dynamic stiffness values of the attachment points obtained through simulation in the initial design stage and the dynamic stiffness values obtained through actual test verification in the later stage. Moreover, the dynamic stiffness of the attachment point is directly affected by the stiffness and strength characteristics of its surrounding structure. Once the structure design is completed, due to limitations in manufacturing, assembly, and materials, etc., it is often very difficult to modify or adjust the dynamic stiffness of the attachment point. Therefore, if there is a large difference between the simulation value in the initial design stage and the measured value in the later stage, this will directly lead to a decline in the performance of the mount system, and then have a direct negative impact on the performance and development progress of the whole vehicle. In order to ensure that the performance of the mount system meets the expectations and improve the consistency between design simulation and actual test, it is necessary to ensure the accuracy of the simulation in the initial design stage.

[0039] Based on this, the present application proposes a method for dynamically simulating and verifying the stiffness of the mount attachment point to verify the accuracy of the dynamic stiffness simulation of the attachment point, thereby improving the reliability and accuracy of the simulation to ensure that the performance of the mount system meets the expectations.

[0040] Please refer to Figure 2, a flowchart of a method for simulating and verifying the dynamic stiffness of a suspension attachment point shown in an exemplary embodiment of the present application. As Figure 2 shown, in an exemplary embodiment, the method for simulating and verifying the dynamic stiffness of a suspension attachment point at least includes steps S210 to S250, which are introduced in detail as follows:

[0041] Step S210, obtain the target attachment point of the suspension bracket.

[0042] In an embodiment of the present application, the attachment point of the suspension bracket is the connection point between the suspension element (such as a suspension bushing) and the suspension bracket in the vehicle, and a to-be-tested attachment point is selected as the target attachment point.

[0043] Step S220, respectively simulate and test the dynamic stiffness of the target attachment point in a preset direction to obtain a simulated dynamic stiffness curve and a measured dynamic stiffness curve.

[0044] In an embodiment of the present application, the abscissa of the simulated dynamic stiffness curve and the measured dynamic stiffness curve respectively represents the frequency point, and the ordinate represents the dynamic stiffness.

[0045] Specifically, construct a finite element model of the suspension bracket, and use the target attachment point as the response point of the finite element model; apply a load in a preset direction to the response point of the finite element model according to a preset mapping relationship to obtain a simulated dynamic stiffness curve corresponding to the preset direction. The preset mapping relationship is the mapping relationship between the frequency point and the force, and the load is characterized as the force; perform a dynamic stiffness test on the target attachment point in the preset direction based on the preset mapping relationship to obtain a measured dynamic stiffness curve corresponding to the preset direction.

[0046] In an embodiment of the present application, the simulation analysis of the dynamic stiffness requires the following execution steps: first, construct a finite element model, and then perform mesh division, material property assignment, boundary condition setting, creation of applied loads, definition of output requirements, calculation of the finite element model, and processing of the calculation results on the finite element model, which are described in detail as follows:

[0047] First, mesh division of the finite element model is the basis of finite element analysis. Compared with modal analysis, high-quality mesh division can provide more accurate dynamic stiffness simulation results, help accurately evaluate the dynamic stiffness characteristics of the suspension system, improve the simulation calculation efficiency, and reduce the calculation time and resource consumption.

[0048] Second, accurately assign material properties to the finite element model according to the material parameters of the suspension bracket, such as key parameters such as the density, elastic modulus, and Poisson's ratio of the material, to ensure that the finite element model exhibits mechanical properties and responses consistent with the actual situation in the simulation and improve the reliability of the simulation.

[0049] Third, set the boundary conditions of the finite element model, that is, consider the stiffness characteristics of the bolt joints in the mounting bracket, and use spring elements, etc. to simulate it to constrain the finite element model, ensuring that it can truly reflect the dynamic performance of the mounting bracket at the connection part during the simulation and improving the accuracy and reliability of the simulation.

[0050] Fourth, applying a load means creating a load within a preset frequency range. This load is a unit dynamic load in a preset direction and varies with the frequency within the preset frequency range. As the excitation of the finite element model, it is used to simulate the dynamic excitation received by the target attachment point during actual testing. Among them, applying dynamic loads at different frequencies can evaluate the dynamic stiffness characteristics of the target attachment point under different working conditions and provide the reliability of the simulation.

[0051] Fifth, defining the output requirements of the finite element model includes setting the position of the response points and the type of response data, that is, presetting the type of response data. The response points are defined based on the attachment points, and the selection of their positions needs to consider the difficulty of arranging sensors during actual testing and the degree of attention of the response points.

[0052] Sixth, calculate the finite element model after performing the above steps to obtain the dynamic response of the response points in the finite element model, that is, the response curve of the set response data, such as the response curve of acceleration, and then obtain the simulated dynamic stiffness curve of the attachment point in the preset direction, that is, the simulated stiffness curves of the attachment point in the three directions of X, Y, and Z (i.e., the three directions of the horizontal axis, vertical axis, and vertical axis). Among them, the finite element model can be calculated using Optistruct (i.e., the solver), or other finite element solvers to output the response curve.

[0053] In an embodiment of the present application, in order to evaluate the dynamic stiffness characteristics of the target attachment point under different working conditions, determine the force applied at each frequency point based on the preset mapping relationship; determine the force applied at each frequency point based on the preset mapping relationship; use the force applied at each frequency point as the magnitude of the load of the finite element model and apply it to the response points of the finite element model in the preset direction to simulate the preset response data of the target attachment point changing with frequency under the action of force. The preset response data includes any one of acceleration, displacement, and circular frequency to improve the reliability and practicability of the simulation.

[0054] In an embodiment of the present application, the steps of mesh generation and load creation can be implemented by Hypermesh (a finite element model preprocessing software), or by using other software with the same function.

[0055] In an embodiment of the present application, the preset frequency range can be set to 50 - 500 Hz (Hertz), or it can be adjusted according to actual needs.

[0056] In an embodiment of the present application, a unit dynamic load varying with frequency can be generated through a Load Collector to improve the efficiency of applying the load.

[0057] Please refer to Figure 3 and Figure 4 , which are schematic diagrams of the finite element model and the dynamic stiffness test of the attachment point shown in an exemplary embodiment of the present application. Figure 3 is Figure 4 the finite element model of the shown suspension bracket. When performing an actual dynamic stiffness test on the target attachment point, sensors need to be arranged on the suspension bracket according to the positions of the response points, and then an external force is applied to the target attachment point of the suspension bracket from a preset direction to ensure accurate acquisition of the response corresponding to the preset response data of the target attachment point.

[0058] Exemplarily, taking the type of the sensor as an acceleration sensor, first, the suspension bracket is firmly installed on the test fixture using bolts, and the pre-tightening torque of the bolts is greater than the saturated pre-tightening torque to ensure that the suspension bracket will not affect the test results due to loosening or deformation during the test, which helps to provide the accuracy and reliability of the test; second, each component of the acquisition system (such as a force hammer, an acceleration sensor, a computer, and a data acquisition instrument) is connected to ensure that the data generated during the test can be accurately and real-time transmitted to the computer for processing and analysis; then, the acceleration sensor is arranged on the suspension bracket according to the positions of the response points in the finite element model, and the suspension bracket is struck with a force hammer from a preset direction. The striking point should strictly refer to the response points in the finite element model. The acceleration response of the target attachment point is collected through the acceleration sensor. Finally, the acceleration frequency response curve corresponding to the preset direction, that is, the test response curve of the acceleration, is obtained through data processing by the computer, and the acceleration admittance is performed on it to obtain the test dynamic stiffness curve.

[0059] In an embodiment of the present application, since the suspension bracket may deform and vibrate in the X, Y, and Z directions when subjected to dynamic loads, therefore, in order to comprehensively evaluate the dynamic stiffness of the target attachment point structure, it is necessary to respectively perform simulation verification on the dynamic stiffness in the X, Y, and Z directions to improve the reliability and comprehensiveness of the simulation.

[0060] Specifically, a load in a preset direction is applied to the response points of the finite element model, and the simulation response curve formed by the preset response data varying with frequency in the preset direction is calculated; a force is applied to the target attachment point in the preset direction, and the measured response curve formed by the preset response data varying with frequency in the preset direction is measured; the source point admittance calculation is respectively performed according to the simulation response curve and the measured response curve to obtain the simulation dynamic stiffness curve and the measured dynamic stiffness curve.

[0061] In one embodiment of the present application, the horizontal axis of the simulated response curve and the measured response curve represents frequency, and the vertical axis represents the preset response data.

[0062] In one embodiment of the present application, for different types of preset response data, the expression for calculating the source point admittance is as follows:

[0063]

[0064] Among them, IPI in Equation (2) represents the dynamic stiffness, F represents the amplitude of the force, with the unit of N (Newton), X represents the amplitude of the displacement, with the unit of m (meter), A represents the amplitude of the acceleration, with the unit of m / s 2 (meters per second squared), and ω represents the circular frequency, with the unit of Hz (Hertz).

[0065] Step S230: Calculate based on the simulated dynamic stiffness curve and the measured dynamic stiffness curve to determine the amplitude difference and the phase difference.

[0066] Specifically, convert the simulated dynamic stiffness curve and the measured dynamic stiffness curve into discrete signals respectively to obtain the simulated signal and the measured signal; calculate the means of the simulated signal and the measured signal respectively to obtain the first mean and the second mean; calculate based on the first mean and the second mean to determine the amplitude difference and the phase difference between the simulated signal and the measured signal.

[0067] In one embodiment of the present application, the expressions for calculating the means of the simulated signal and the test signal are as follows:

[0068]

[0069]

[0070] Among them, a(x i ) in Equation (3) represents the simulated signal corresponding to the i-th frequency point, that is, the simulated value of the dynamic stiffness corresponding to the i-th frequency point, represents the mean of the simulated signal, b(y i ) in Equation (4) represents the measured signal corresponding to the i-th frequency point, that is, the measured value of the dynamic stiffness corresponding to the i-th frequency point, represents the mean of the measured signal, and i in Equations (3) and (4) represents the i-th frequency point, and N represents the number of frequency points.

[0071] In one embodiment of the present application, calculate the square root of the ratio between the first mean and the second mean, and then calculate the difference between the square root of the ratio between the first mean and the second mean and the preset threshold to obtain the amplitude difference, where the preset threshold is usually set to 1. The expression for calculating the amplitude difference is as follows:

[0072]

[0073] Among them, M in formula (5) represents the amplitude difference, represents the mean value of the simulation signal, represents the mean value of the measured signal.

[0074] In an embodiment of the present application, calculate the mean value of the product (i.e., point-by-point multiplication) between the simulation signal and the measured signal as the third mean value. The third mean value reflects the average effect of the interaction between the simulation signal and the measured signal at discrete frequency points; calculate the ratio of the third mean value and the square root of the product between the first mean value and the second mean value, and use the result of the ratio calculation as the cosine value; calculate the target angle according to the inverse cosine function for the preset value, and finally multiply the target angle by the reciprocal of pi to obtain the phase difference.

[0075] In an embodiment of the present application, the expression for calculating the phase difference is as follows:

[0076]

[0077]

[0078] Among them, in formula (6), represents the third mean value, a(x i ) represents the simulation signal corresponding to the i-th frequency point, b(y i ) represents the measured signal corresponding to the i-th frequency point, N represents the number of frequency points, and P in formula (7) represents the phase difference, represents the mean value of the simulation signal, represents the mean value of the measured signal.

[0079] Step S240, calculate according to the amplitude and the phase difference to determine the combined metric.

[0080] Specifically, calculate the sum of squares between the amplitude and the phase difference to determine the target sum of squares; calculate according to the preset threshold and the target sum of squares to determine the combined metric.

[0081] In an embodiment of the present application, the expression for determining the combined metric is as follows:

[0082]

[0083] Among them, C in formula (8) represents the combined metric, M represents the amplitude difference, P represents the phase difference, and the preset threshold is set to 1. Additionally, the closer the simulated value and the measured value of the dynamic stiffness of the target attachment point are, the closer the absolute values of the amplitude difference and the phase difference between the simulated signal and the measured signal are to 0. Based on this, it can be seen from formula (8) that when the combined metric is closer to the preset threshold, the simulated value and the measured value of the dynamic stiffness of the target attachment point are closer. The method of simulation verification is simple and efficient.

[0084] Step S250: Compare the combined metric with the preset accuracy to determine the simulation verification result of the dynamic stiffness in the preset direction.

[0085] Specifically, compare the combined metric with the preset accuracy corresponding to the preset direction. The preset directions include the horizontal axis direction, the vertical axis direction, and the vertical axis direction, and the preset direction and the preset accuracy are in one-to-one correspondence. If the combined metric is greater than or equal to the preset accuracy, it is determined that the simulation verification result of the dynamic stiffness in the preset direction is qualified. If the combined metric is less than the preset accuracy, it is determined that the simulation verification result of the dynamic stiffness in the preset direction is unqualified, and the dynamic stiffness simulation of the target attachment point is corrected.

[0086] In an embodiment of the present application, the preset accuracy can be adjusted according to actual needs. Taking the preset accuracy of 0.60 as an example, when the combined metric is less than 0.60, the simulation verification result is unqualified, and there is a large difference between the simulated value and the measured value of the dynamic stiffness of the target attachment point. When the combined metric satisfies 0.60 ≤ C ≤ 1 (where C is the combined metric), the simulation verification result is qualified, and the difference between the simulated value and the measured value of the dynamic stiffness of the target attachment point is small, meeting the requirements of engineering practice.

[0087] In an embodiment of the present application, since the requirements for simulation accuracy are different in different directions, the preset accuracies for different preset directions can be set separately to improve the flexibility of simulation verification. Only when the simulation verifications of the dynamic stiffness of the target attachment point in all preset directions are qualified can the simulation of the dynamic stiffness of this target attachment point be verified as qualified, determined to meet the requirements, and ensure that the error between the simulation and the measurement is within an acceptable range.

[0088] In an embodiment of the present application, in order to further improve the flexibility and practicality of simulation verification, the preset accuracy corresponding to the preset direction can also be adjusted according to the vehicle models applicable to the suspension bracket. For example, establish a mapping relationship between different vehicle models, preset directions, and preset accuracies, obtain the vehicle model to which the suspension bracket is to be applied, match this mapping relationship based on the vehicle model to be applied and the preset direction, and determine the preset accuracy. In this way, when the vehicle model is positioned high-end and has high performance requirements, a higher preset accuracy can be set to further reduce the difference between the simulated value and the measured value. When the vehicle model is positioned low-end and has general performance requirements, a lower preset accuracy can be set, thereby meeting multiple requirements such as development efficiency, cost, and vehicle model positioning.

[0089] In an embodiment of the present application, when the accuracy of the dynamic stiffness simulation is unqualified, the finite element model needs to be corrected, and then the simulation analysis is performed again based on the corrected finite element model until the inspection is qualified. Among them, correcting the finite element model includes: First, checking the basic parameters of the finite element model, and the basic parameters include but are not limited to element type, mesh division, material properties, and connection method, and ensuring that the simulation model is consistent with the state of the tested suspension bracket, such as subsystem state, weight, tooling, boundary conditions, etc., which helps to reduce the deviation of the simulation results caused by incorrect finite element model settings. Second, analyzing the reasons for the differences, comparing the differences between the simulation analysis results and the test results, that is, the differences between the simulation dynamic stiffness curve and the measured dynamic stiffness curve. Among them, methods such as modal strain energy analysis, transfer path analysis (TPA), operating deflection shapes (ODS), node contribution, and modal contribution can be used for difference analysis to find out the reasons for the differences for correction. Third, iteratively verifying the simulation model. Based on the results of the difference reason analysis, determine the factors that may cause inaccurate simulation results, and correct the identified factors one by one, such as adjusting the mesh division, updating the material properties, optimizing the connection method, etc. After each correction, perform the simulation again and calculate the new combined metric. If it is determined that the simulation inspection result is still unqualified according to the new combined metric, continue to iterate the above steps. In this way, through iterative verification, the true test results can be gradually approximated, and the accuracy of the simulation can be improved.

[0090] In an embodiment of the present application, after correcting the simulation model, the corrected finite element model is used for simulation analysis in multiple vehicle model projects to ensure the consistency of the simulation. In this way, it helps to improve the reliability and accuracy of the dynamic stiffness simulation in different vehicle model projects. And summarize the problems involved in the correction process to form a standardized document for guiding the development of subsequent vehicle model projects, which helps to standardize the correction process of the finite element model and improve the development efficiency and quality.

[0091] Please refer to Figures 5 to 7 , which are schematic diagrams showing the comparison of the dynamic stiffness curves in the horizontal axis direction, vertical axis direction, and vertical axis direction shown in an exemplary embodiment of the present application. Figures 5 to 7 The abscissa in is frequency, with the unit of Hz, and the ordinate is dynamic stiffness, with the unit of N / mm. The curve test is the measured dynamic stiffness curve obtained by testing, the curve base represents the simulation dynamic stiffness curve obtained by simulation, and the curve case is the simulation dynamic stiffness curve after correcting the dynamic stiffness simulation. It can be clearly seen from Figures 5 to 7 that when the inspection of the dynamic stiffness simulation is unqualified, after correction, the difference between the previous dynamic stiffness simulation and the test is reduced.

[0092] In one embodiment of the present application, the suspension system may include multiple suspensions, and there are multiple attachment points. When verifying whether the accuracy of the dynamic stiffness simulation of the entire suspension system is qualified, the mean value between the combined metrics corresponding to all attachment points in each preset direction can be calculated. If the mean value is greater than or equal to the preset mean value, it is qualified; if the mean value is less than the preset mean value, it is unqualified. In this way, the efficiency of the dynamic stiffness simulation inspection of the entire suspension system is improved.

[0093] In one embodiment of the present application, an example of the combined metrics before and after the dynamic stiffness simulation verification is shown in Table 1:

[0094] Table 1

[0095]

[0096] As can be seen from Table 1, taking the attachment points of the right suspension, left suspension, and rear suspension included in the suspension system at the powertrain as examples, the simulation inspection is unqualified. After the finite element model is corrected, the combined metric C corresponding to each target attachment point has a significant improvement compared to before the correction, that is, the accuracy of the dynamic stiffness simulation is improved, ensuring the reliability and accuracy of the dynamic stiffness simulation.

[0097] Please refer to Figure 8 , which is a schematic diagram of the overall process of the dynamic stiffness simulation verification shown in an exemplary embodiment of the present application. The overall process of the dynamic stiffness simulation verification of the suspension attachment points includes: First, perform finite element modeling on the suspension bracket, simulate the dynamic stiffness of the target attachment point based on the finite element model to obtain the simulation results, and, test the dynamic stiffness of the target attachment point to obtain the test data, that is, execute step S220; Then, calculate the combined metric C according to the simulation results and the test data, and determine whether it meets the requirements, that is, execute steps S230 to S250. If it does not meet the requirements, analyze the error factors between the simulation and the test based on the simulation results and the test data, determine the correction parameters of the simulation model (i.e., the finite element model), correct the finite element model, and simulate the dynamic stiffness of the target attachment point again according to the corrected finite element model, and recalculate the combined metric C to determine whether it meets the requirements. Finally, until the combined metric C meets the requirements, that is, the combined metric C is greater than or equal to the preset accuracy, the finite element model is no longer corrected.

[0098] Please refer to Figure 9 , which is a schematic diagram of the overall architecture of the dynamic stiffness simulation verification shown in an exemplary embodiment of the present application. As Figure 9The architecture shown includes a simulation analysis module, a test model, a parameter correction model, and a comparison and judgment model. Among them, the simulation analysis module is used to construct a finite element model and simulate the dynamic stiffness of the target attachment point. The test model is used to test the dynamic stiffness of the target attachment point. The parameter correction model is used to correct the finite element model when the gap between the simulation and the test of the dynamic stiffness does not meet the requirements. The comparison and judgment module is used to determine whether the gap between the simulation and the test of the dynamic stiffness meets the requirements. Among them, Figure 9 The specific execution methods of each module are described in the above embodiments and will not be elaborated here.

[0099] In an embodiment of the present application, the steps of simulating and verifying the dynamic stiffness of the suspension attachment point described in steps S220 to S250 can also be applied to other connection parts with suspension bushings in the suspension system, such as the connection between the engine and the body or the subframe. Taking it as the target attachment point, it is not limited to the suspension bracket.

[0100] The method for simulating and verifying the dynamic stiffness of the suspension attachment point provided by the present application has the following advantages: Based on the simulated dynamic stiffness curve and the measured dynamic stiffness curve in the preset direction, a combined metric for measuring the difference between the dynamic stiffness simulation and the test is calculated to verify the accuracy of the simulation, improving the accuracy and reliability of the dynamic stiffness simulation, and helping to save the R & D time and the later rectification cost of the suspension system.

[0101] Please refer to Figure 10 , which is a block diagram of a device for simulating and verifying the dynamic stiffness of a suspension attachment point shown in an exemplary embodiment of the present application. As Figure 10 shown, in an exemplary embodiment, the device for simulating and verifying the dynamic stiffness of a suspension attachment point at least includes an acquisition module 1010, a simulation and test module 1020, a first calculation module 1030, a second calculation module 1040, and a comparison module 1050, which are introduced in detail as follows:

[0102] The acquisition module 1010 is used to acquire the target attachment point of the suspension bracket;

[0103] The simulation and test module 1020 is used to simulate and test the dynamic stiffness of the target attachment point in the preset direction respectively to obtain a simulated dynamic stiffness curve and a measured dynamic stiffness curve;

[0104] The first calculation module 1030 is used to calculate according to the simulated dynamic stiffness curve and the measured dynamic stiffness curve to determine the amplitude difference and the phase difference;

[0105] The second calculation module 1040 is used to calculate according to the amplitude and the phase difference to determine the combined metric

[0106] The comparison module 1050 is used to compare the combined metric with the preset accuracy to determine the simulation verification result of the dynamic stiffness in the preset direction.

[0107] In an embodiment of the present application, the functions of the simulation test module can be jointly implemented by the Figure 9 simulation analysis module and the test module therein, and the functions of the first calculation module, the second calculation module, and the comparison module can be implemented by the Figure 9 comparison and judgment module therein.

[0108] It should be noted that the dynamic stiffness simulation verification device for the suspension attachment point provided in the above embodiment and the dynamic stiffness simulation verification method for the suspension attachment point provided in the above embodiment belong to the same concept. The content of the operations performed by each module has been described in detail in the method embodiment, and will not be elaborated here.

[0109] The present application also provides an electronic device, including: a processor, a memory, and a communication bus; the communication bus is used to connect the processor and the memory; the processor is used to execute a computer program stored in the memory to implement the dynamic stiffness simulation verification method for the suspension attachment point in the above embodiment.

[0110] Please refer to Figure 11 , which shows a schematic structural diagram of a computer system of an electronic device suitable for implementing the embodiments of the present application. It should be noted that Figure 11 the shown computer system 1100 of the electronic device is only an example and should not impose any limitation on the functions and usage scope of the embodiments of the present application.

[0111] As Figure 11 shown, the computer system 1100 includes a central processing unit (CPU) 1101, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1102 or a program loaded from a storage section 1108 into a random access memory (RAM) 1103, such as executing the method in the above embodiment. In the RAM 1103, various programs and data required for system operation are also stored. The CPU 1101, the ROM 1102, and the RAM 1103 are connected to each other through a bus 1104. An input / output (I / O) interface 1105 is also connected to the bus 1104.

[0112] The following components are connected to the I / O interface 1105: an input section 1106 including a keyboard, a mouse, etc.; an output section 1107 including such as a Cathode Ray Tube (CRT), a Liquid Crystal Display (LCD), etc. and a speaker, etc.; a storage section 1108 including a hard disk, etc.; and a communication section 1109 including a network interface card such as a LAN (Local Area NetworK) card, a modem, etc. The communication section 1109 performs communication processing via a network such as the Internet. The drive 1110 is also connected to the I / O interface 1105 as required. A removable medium 1111, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 1110 as required so that a computer program read from it can be installed into the storage section 1108 as required.

[0113] Specifically, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product that includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication section 1109, and / or installed from the removable medium 1111. When the computer program is executed by a central processing unit (CPU) 1101, various functions defined in the system of the present application are executed.

[0114] The present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor of a computer, the computer is enabled to execute the vehicle-end data forwarding method as described above. The computer-readable storage medium may be included in the electronic device described in the above embodiment, or may exist separately without being assembled into the electronic device.

[0115] It should be noted that the computer-readable medium shown in the embodiments of the present application can be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of the computer-readable storage medium may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or as a part of a carrier wave, which carries a computer-readable computer program. Such a propagated data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0116] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present application. Among them, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the above module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order from that marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram or flowchart, and the combination of blocks in the block diagram or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions.

[0117] The units involved in the embodiments described in this application can be implemented in software or in hardware, and the described units can also be provided in a processor. Among them, the names of these units do not, in some cases, constitute a limitation on the unit itself.

[0118] The above embodiments are only used to exemplarily illustrate the principles and effects of this application, rather than to limit this application. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed in this application should still be covered by the claims of this application.

Claims

1. A method for simulating and verifying the dynamic stiffness of a suspension attachment point, characterized in that: The method comprises: Obtaining a target attachment point of the suspension bracket; Simulating and testing the dynamic stiffness of the target attachment point in a preset direction to obtain a simulated dynamic stiffness curve and a measured dynamic stiffness curve; Calculating according to the simulated dynamic stiffness curve and the measured dynamic stiffness curve to determine the amplitude difference and the phase difference; Performing calculation based on the amplitude and the phase difference to determine a combined metric; The combined metric is compared with a preset accuracy to determine a simulation verification result of the dynamic stiffness in the preset direction.

2. The method for dynamic stiffness simulation verification of a suspension attachment point according to claim 1, characterized in that: The dynamic stiffness of the target attachment point in a preset direction is simulated and tested respectively to obtain a simulated dynamic stiffness curve and a measured dynamic stiffness curve, including: Constructing a finite element model of the suspension bracket, and using the target attachment point as a response point of the finite element model; Applying a load in the preset direction to the response point of the finite element model according to a preset mapping relationship to obtain the simulated dynamic stiffness curve corresponding to the preset direction, wherein the preset mapping relationship is a mapping relationship between a frequency point and a force, and the load is characterized as a force; Based on the preset mapping relationship, a dynamic stiffness test is performed on the target attachment point in the preset direction to obtain a measured dynamic stiffness curve corresponding to the preset direction.

3. The dynamic stiffness simulation verification method of the suspension attachment point according to claim 2, characterized in that: The step of applying a load in the preset direction to a response point of the finite element model according to a preset mapping relationship comprises: Determine the force applied at each frequency point based on the preset mapping relationship; The force applied at each frequency point is used as the magnitude of the load of the finite element model and is applied to the response point of the finite element model in a preset direction to simulate the preset response data of the target attachment point that changes with frequency under the action of the force, and the preset response data includes any one of acceleration, displacement and circular frequency.

4. The method for simulating and verifying the dynamic stiffness of a suspension attachment point according to claim 1, characterized in that: The calculating according to the simulated dynamic stiffness curve and the measured dynamic stiffness curve to determine the amplitude difference and the phase difference includes: Converting the simulated dynamic stiffness curve and the measured dynamic stiffness curve into discrete signals respectively to obtain a simulated signal and a measured signal; Calculating the means of the simulation signal and the measured signal respectively to obtain a first mean value and a second mean value; Calculation is performed based on the first mean value and the second mean value to determine the amplitude difference and the phase difference between the simulated signal and the measured signal.

5. The method for simulating and verifying the dynamic stiffness of a suspension attachment point according to claim 1, characterized in that: The calculating according to the amplitude and the phase difference to determine the combined metric includes: Calculating the sum of squares between the amplitude and the phase difference to determine a target sum of squares; The combined metric is determined by performing calculation based on a preset threshold and the target sum of squares.

6. The method for dynamic stiffness simulation verification of a suspension attachment point according to any one of claims 1 to 5, characterized in that: The comparing the combined metric with the preset accuracy to determine the simulation verification result of the dynamic stiffness in the preset direction includes: Comparing the combined metric with the preset precision corresponding to the preset direction, the preset direction includes a horizontal axis direction, a longitudinal axis direction and a vertical axis direction, and the preset direction and the preset precision correspond one to one; If the combined metric is greater than or equal to the preset accuracy, determining that the simulation verification result of the dynamic stiffness in the preset direction is qualified; If the combined metric is less than the preset accuracy, it is determined that the simulation verification result of the dynamic stiffness in the preset direction is unqualified, and the dynamic stiffness simulation of the target attachment point is corrected.

7. The method for simulating and verifying the dynamic stiffness of a suspension attachment point according to claim 3, characterized in that: The obtaining of the simulated dynamic stiffness curve and the measured dynamic stiffness curve comprises: Applying the load in the preset direction to the response point of the finite element model, and calculating a simulation response curve formed by the preset response data changing with frequency in the preset direction; Applying a force to the target attachment point in the preset direction, and measuring a measured response curve formed by the preset response data changing with frequency in the preset direction; The source point admittance calculation is performed according to the simulated response curve and the measured response curve respectively to obtain the simulated dynamic stiffness curve and the measured dynamic stiffness curve.

8. A dynamic stiffness simulation verification device for a suspension attachment point, characterized in that: The device comprises: An acquisition module, used for acquiring a target attachment point of the suspension bracket; A simulation test module, used to simulate and test the dynamic stiffness of the target attachment point in a preset direction, respectively, to obtain a simulated dynamic stiffness curve and a measured dynamic stiffness curve; A first calculation module, used for performing calculation according to the simulated dynamic stiffness curve and the measured dynamic stiffness curve to determine the amplitude difference and the phase difference; A second calculation module is used to calculate according to the amplitude and the phase difference to determine the combined metric The comparison module is used to compare the combined metric with a preset accuracy to determine a simulation verification result of the dynamic stiffness in the preset direction.

9. An electronic device, characterized in that: include: processor, memory, and communications bus; The communication bus is used to connect the processor and the memory; The processor is configured to execute the computer program stored in the memory to implement the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and the computer program is used to make a computer execute the method according to any one of claims 1 to 7.

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