Correction methods for high-speed uniformity data and their application in cavity noise analysis

Abstract

This invention relates to a method for correcting high-speed uniformity data and its application in tire cavity noise analysis. The correction method includes the following steps: installing a test object at the axle head of a high-speed uniformity testing device; applying excitation to the surface of the test object; installing a first detection device for measuring the input signal at the excitation position of the test object and a second detection device for measuring the output signal at the output position; establishing a transfer function with the test frequency as the independent variable and the transmissivity as the dependent variable; conducting a high-speed uniformity test using the high-speed uniformity testing device and obtaining high-speed uniformity data; calculating the frequency at each speed and harmonic order in the high-speed uniformity data; obtaining the transmissivity corresponding to each frequency based on the transfer function; and dividing the high-speed uniformity data by the transmissivity at the corresponding frequency to obtain the corrected high-speed uniformity data. This method can correct high-speed uniformity data and expand the testable frequency range of the high-speed uniformity testing device.

Description

Technical Field

[0001] This invention belongs to the field of tire testing technology, and in particular relates to a method for correcting high-speed uniformity data and its application in tire cavity noise analysis. Background Technology

[0002] Tire cavity noise refers to the vibration of air inside the tire caused by road surface roughness and tire unevenness during driving. This vibration generates longitudinal and radial energy differences, which are then transmitted through the tire to the rim and subsequently to the vehicle body structure, resulting in cabin noise. Different tire sizes have different cavity volumes and shapes, leading to variations in tire cavity noise frequencies. Typically, the main frequency of cavity noise in passenger car radial tires is between 180 and 250 Hz.

[0003] Tire cavity noise significantly impacts ride comfort, and assessing its level during tire development and production is a major challenge for tire manufacturers. Traditionally, tire cavity noise is detected through spectrum analysis of real-vehicle tests; however, this method is costly, time-consuming, and the results are easily affected by external factors.

[0004] Chinese invention patent CN112549868A proposes a method for detecting and analyzing tire cavity noise. This method utilizes a high-speed homogeneity testing device to obtain the amplitude and corresponding frequency of each harmonic of the tire, and then analyzes the data to determine the magnitude of the tire cavity noise. Compared with actual vehicle testing, this detection and analysis method is simpler to operate, lower in cost, shorter in cycle time, and provides more objective and reliable results.

[0005] Because the measurement system of high-speed uniformity testing equipment has inherent modal characteristics, the maximum testable frequency is generally below 200Hz. As the test frequency increases and approaches its natural frequency, the test data gradually becomes distorted, making it impossible to characterize the cavity mode of the tire at high frequencies. This results in a narrow observation range for tire cavity modes in high-speed uniformity testing, effective only for tires with cavity frequencies in the range of 180–200Hz, limiting the application scope of high-speed uniformity testing for detecting and analyzing tire cavity noise. To solve these problems, high-speed uniformity testing equipment manufacturers are committed to creating testing equipment with higher natural frequencies. However, this development cost is very high, and tire manufacturers face long equipment upgrade cycles due to laboratory space planning or funding issues. Therefore, they are caught in a dilemma: upgrading equipment is costly, while maintaining the existing equipment results in low utilization. Summary of the Invention

[0006] To address at least one shortcoming in the related technologies, the present invention provides a method for correcting high-speed uniformity data and its application in tire cavity noise analysis, thereby correcting high-speed uniformity data and expanding the frequency range that can be tested by high-speed uniformity equipment.

[0007] The first aspect of this application provides a method for correcting high-speed uniformity data, comprising the following steps:

[0008] The test object is installed at the shaft head of the high-speed uniformity equipment;

[0009] An excitation is applied to the surface of the test object. A first detection device for measuring the input signal is installed at the excitation position of the test object. A position different from the excitation position is selected as the output position. A second detection device for measuring the output signal is installed at the output position.

[0010] Establish a transfer function with the test frequency as the independent variable and the transfer rate as the dependent variable; where the transfer rate is the ratio of the Laplace transform of the output signal to the Laplace transform of the input signal, in dB.

[0011] High-speed uniformity tests were conducted using high-speed uniformity equipment, and high-speed uniformity data were obtained.

[0012] Calculate the frequencies at each harmonic order for each velocity in high-speed uniformity data:

[0013] f=V*n / (3.6*π*D) (1)

[0014] In the formula, f is the frequency corresponding to a certain harmonic order at a certain speed, in Hz; V is the test speed of the high-speed uniformity test, in km / h; n is the harmonic order; and D is the outer diameter of the inflated tire, in meters.

[0015] The transfer rate corresponding to each frequency f is obtained based on the transfer function;

[0016] The corrected high-speed uniformity data are obtained by dividing the high-speed uniformity data by the transmissivity at the corresponding frequency.

[0017] In some embodiments of the first aspect, the test object is a tire-rim assembly or an annular substitute, wherein the mass of the annular substitute is 16 to 25 kg.

[0018] In some embodiments of the first aspect, the output position is located on the surface of the test object opposite the excitation position.

[0019] In some embodiments of the first aspect, the excitation direction is at least one of radial, lateral, and longitudinal.

[0020] In some embodiments of the first aspect, the first detection device can measure the force and acceleration at the excitation position, the second detection device can measure the force and acceleration at the output position, the input signal is the ratio of input acceleration to input force, and the output signal is the ratio of output acceleration to output force.

[0021] In some embodiments of the first aspect, the step of establishing the transfer function specifically includes:

[0022] Establish the frequency response functions of the input signal and the output signal: the frequency response function of the input signal has the test frequency as the independent variable and the input signal as the dependent variable; the frequency response function of the output signal has the test frequency as the independent variable and the output signal as the dependent variable.

[0023] The ratio of the frequency response function of the output signal to the frequency response function of the input signal is the transfer function.

[0024] In some embodiments of the first aspect, the step of establishing the transfer function further includes a step of fitting the data of the transfer function, wherein the fitting step specifically includes:

[0025] The starting point P1 for function fitting is determined to be (n, 1+a), where [0, a] is the acceptable range of distortion rate, and n is the frequency corresponding to the transfer rate 1+a;

[0026] The endpoint P2 of the function fitting is determined to be (250+f) rmax ,F(250+f rmax )), f rmax To cover the maximum rolling frequency for all test speeds and tire rolling circumferences, F(250+f) rmax () is a frequency of 250+f rmax Transmission rate, rolling frequency f r =V / C, where V is the test speed and C is the tire rolling circumference;

[0027] Take at least 10 fitting points every 100Hz starting from P1;

[0028] By fitting the data of each transfer function, a univariate polynomial function equation for the transfer function is obtained.

[0029] In some embodiments of the first aspect, the goodness-of-fit R-Sq value is used as the criterion, and a goodness-of-fit R-Sq > 95% is considered to be effective.

[0030] A second aspect of this application provides an application of a method for correcting high-speed uniformity data according to any embodiment of the first aspect in tire cavity noise analysis, comprising the following steps:

[0031] The tire-rim assembly to be tested was tested using a high-speed homogeneity tester to obtain high-speed homogeneity data.

[0032] The high-speed uniformity data is corrected using a high-speed uniformity data correction method as described in any embodiment of the first aspect;

[0033] Based on the corrected high-speed uniformity data analysis, the amplitude abrupt change points are determined to identify the frequency, harmonic value, and risk of actual vehicle cavity noise.

[0034] In some embodiments of the second aspect, the application further includes the step of establishing a predictive standard for the generation of actual vehicle cavity noise: selecting one or more tire sizes for subjective cavity noise testing, and obtaining the perceptible cavity noise harmonic value as a predictive standard based on the subjective cavity noise test results combined with corrected high-speed uniformity data; when the cavity noise harmonic value of the corrected high-speed uniformity data obtained in subsequent tests is equal to or greater than the established predictive standard, it is predicted that actual vehicle cavity noise will be generated.

[0035] Compared with the prior art, the advantages and positive effects of the present invention are as follows: The high-speed uniformity data correction method provided in at least one embodiment of the present application is based on the black box model theory. According to the transfer function and the test data output by the high-speed uniformity test, the axle non-uniform force caused by tire non-uniformity can be obtained by reverse calculation. This effectively removes the limitation caused by the modal characteristics of the measurement system, and expands the observation range of tire cavity noise through high-speed uniformity data from 180Hz to 200Hz to 180Hz to 300Hz. This improves the utilization rate of existing equipment and avoids the high cost of upgrading equipment. Attached Figure Description

[0036] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0037] Figure 1 This is a schematic diagram of tire testing using a high-speed uniformity testing device.

[0038] Figure 2 This is a schematic diagram showing the test sample mounted on a high-speed uniformity device in the high-speed uniformity data correction method provided in the embodiments of this application.

[0039] Figure 3 A schematic diagram illustrating the application of excitation to the test object in the method for correcting high-speed uniformity data provided in the embodiments of this application;

[0040] Figure 4 A comparison chart of transfer function curves for measurement systems of ideal and general equipment;

[0041] Figure 5 A schematic diagram illustrating the principle of the high-speed uniformity data correction method provided in the embodiments of this application;

[0042] Figure 6 This is a graph of the transfer function established in Embodiment 1 of this application.

[0043] In the picture:

[0044] 1. Axle head; 2. Load wheel; 3. Other main body of the high-speed uniformity equipment; 4. Tire and rim assembly; 5. Test object; 61. First detection device; 62. Second detection device; 7. Protrusion. Detailed Implementation

[0045] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0046] Obviously, the accompanying drawings described below are merely some examples or embodiments of this application. Those skilled in the art can apply this application to other similar scenarios based on these drawings without any inventive effort. Furthermore, it is understood that although the efforts made in this development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this application, any changes to design, manufacturing, or production based on the technical content disclosed in this application are merely conventional technical means and should not be construed as insufficient disclosure of the content of this application.

[0047] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0048] A schematic diagram of a high-speed uniformity test for tires using a high-speed uniformity testing device is shown below. Figure 1As shown. The high-speed uniformity testing equipment includes an axle head 1, a load wheel 2, and other main equipment 3. During the high-speed uniformity test, the inflated tire-rim assembly 4 is installed at the axle head 1 of the high-speed uniformity testing equipment. The axle head 1 has a fixed axial position, and the tire-rim assembly 4 has the freedom to rotate around its axial center. Loading is applied using the load wheel 2, causing the tire-rim assembly 4 to rotate around the axial center of the axle head 1 in the opposite direction to that of the load wheel 2. A built-in force sensor is installed at the axial center of the axle head 1. During rotation, the uneven weight, shape, and stiffness of the tire generate uneven forces on the axle center. These forces are output by the measurement system of the high-speed uniformity testing equipment to obtain the high-speed uniformity data of the tire.

[0049] According to Chinese invention patent CN112549868A, if the circumferential non-uniform force measured at the axle is decomposed using Fourier transform, the harmonic components and corresponding frequency distribution of the non-uniform force of the tire operating at high speed can be obtained. When the frequency of the higher harmonic reaches the cavity frequency of the tire, the two will resonate. The magnitude of the resonance energy can be characterized by the amplitude of the non-uniform force harmonic at the corresponding frequency. The magnitude of its value can be used to predict the magnitude of the cavity noise caused by the tire's own non-uniform excitation during actual operation.

[0050] However, due to the inherent modal characteristics of the measurement system in high-speed uniformity testing equipment, the non-uniform force measured at the axis is affected by the measurement system, resulting in some distortion, especially in the relatively high-frequency region. In engineering, transmissibility is used to represent the relationship between the input and output of a black-box model (system). The lower the transmissibility of the measurement system, the more accurate the output measurement data can be to some extent. Figure 4 As shown, the ideal measurement system can guarantee that the transfer rate is still relatively low within 300Hz, while the transfer rate of the measurement system of general equipment on the market is within an acceptable range within 200Hz. However, when the frequency is above 200Hz, the transfer function increases exponentially, resulting in obvious distortion.

[0051] For the reasons mentioned above, when using high-speed uniformity testing equipment to detect and analyze tire cavity noise, the maximum frequency that can generally be tested is below 200Hz. This results in a narrow observation range for tire cavity frequencies in high-speed uniformity testing, which is only effective for tires with cavity frequencies in the range of 180 to 200Hz. This limits the application scope of high-speed uniformity testing for detecting and analyzing tire cavity noise.

[0052] To address the above problems, this application provides a method for correcting high-speed uniformity data, comprising the following steps:

[0053] Test object 5 is installed at the shaft head of the high-speed uniformity equipment, such as... Figure 1 As shown;

[0054] An excitation is applied to the surface of the test object 5. A first detection device 61 for measuring the input signal is installed at the excitation position of the test object 5. Another position different from the excitation position is selected as the output position. A second detection device 62 for measuring the output signal is installed at the output position.

[0055] Establish a transfer function with the test frequency as the independent variable and the transfer rate as the dependent variable; where the transfer rate is the ratio of the Laplace transform of the output signal to the Laplace transform of the input signal, in dB.

[0056] The high-speed homogenization equipment was used to conduct high-speed homogenization tests and obtain high-speed homogenization data.

[0057] Calculate the frequencies at each harmonic order for each velocity in high-speed uniformity data:

[0058] f=V*n / (3.6*π*D) (1)

[0059] In the formula, f is the frequency corresponding to a certain harmonic order at a certain speed, in Hz; V is the test speed of the high-speed uniformity test, in km / h; n is the harmonic order; and D is the outer diameter of the inflated tire, in meters.

[0060] The transfer rate corresponding to each frequency f is obtained based on the transfer function;

[0061] The corrected high-speed uniformity data are obtained by dividing the high-speed uniformity data by the transmissivity at the corresponding frequency.

[0062] In the principle of the correction method proposed in this application, the tire-rim assembly and the tire cavity it forms are simplified into a black box model I, and the measurement system of the high-speed uniformity device is simplified into a black box model II. The simplified models are as follows: Figure 5 As shown. Due to the non-uniformity of tire weight, shape, and stiffness input into black box model I, the output is the axial non-uniform force caused by the tire's non-uniformity. This axial non-uniform force, input into black box model II, is output as high-speed uniformity data. To predict the magnitude of cavity noise caused by the tire's own non-uniformity during actual operation, either the output data of black box model I or the input data of black box model II is needed. However, the actual measured data is the output data of black box model II. Therefore, the input data of black box model II can be obtained by inverse calculation based on the transfer function and output data of black box model II. This input data is more realistic data that excludes the influence of the inherent modal characteristics of the measurement system.

[0063] Based on the above principles, this application uses an excitation method to input the measurement system, collects the input signal and the generated output signal to establish the transfer function of the measurement system. Based on the transfer function and the test data output from the high-speed uniformity test, the axle non-uniform force caused by tire non-uniformity can be calculated in reverse. This effectively removes the limitations caused by the modal characteristics of the measurement system, corrects the distortion of high-speed uniformity data to a certain extent, and expands the testable frequency range of the high-speed uniformity equipment. It is understood that the transfer function of a measurement system can be considered a constant. Therefore, after obtaining the transfer function of a certain high-speed uniformity equipment measurement system, subsequent corrections of the test data only require using the known transfer function, without needing to establish a new transfer function each time.

[0064] In some embodiments, test object 5 may be a real tire and rim assembly.

[0065] In other embodiments, test object 5 can also be a toroidal substitute to simulate the tire-rim assembly. The mass of the tire-rim assembly varies depending on its size, but is typically in the range of 16–25 kg. Therefore, the mass of the toroidal substitute is also taken within the range of 16–25 kg. Since the transfer function of the entire measurement system is being measured, and the equipment to which the measurement system belongs is fixed to the ground with steel nails and cement, the influence of the mass of the test object on its transfer function is negligible. Using an isotropic material for the toroidal substitute further facilitates the determination of the transfer function.

[0066] In some embodiments, excitation can be applied to the surface of the test object using a force hammer or exciter. The excitation direction is at least one of radial, lateral, and longitudinal, and can be selected according to the transfer function in the desired measurement direction. Radial excitation can be directly applied using a force hammer or exciter; when measuring lateral and longitudinal transfer functions, for ease of operation, a protrusion 7 can be fixed to the surface of the test object, and force input can be applied to the protrusion 7 from the corresponding direction. The radial direction is the most commonly used excitation direction due to its ease of operation and the most representative test data.

[0067] In some embodiments, such as Figure 2 and Figure 3 As shown, the output position is located on the surface of the test object 5 opposite to the excitation position, that is, the output position and the excitation position are set at 180° in the circumferential direction, which facilitates the setting of the second detection device 62.

[0068] In some embodiments, the first detection device 61 can measure the force and acceleration at the excitation position, and the second detection device 62 can measure the force and acceleration at the output position. The input signal is the ratio of input acceleration to input force, and the output signal is the ratio of output acceleration to output force. The first detection device 61 and the second detection device 62 can be devices capable of measuring force and acceleration, such as sensors and / or accelerometers.

[0069] In some embodiments, a frequency response function is used to establish a transfer function. Specifically, the steps for establishing a transfer function include:

[0070] Establish the frequency response functions of the input signal and the output signal: the frequency response function of the input signal has the test frequency as the independent variable and the input signal (the ratio of input acceleration to input force) as the dependent variable; the frequency response function of the output signal has the test frequency as the independent variable and the output signal (the ratio of output acceleration to output force) as the dependent variable.

[0071] The ratio of the frequency response function of the output signal to the frequency response function of the input signal is the transfer function.

[0072] In the above embodiments, the acquired input and output signals can be directly output as the frequency response functions of the input and output signals using a data acquisition device (e.g., a Siemens LMS SCADAS multi-channel data acquisition instrument). It is understood that other existing methods can also be used to establish the transfer function, and this application does not impose any limitations on this.

[0073] The process of establishing the transfer function also includes a step of fitting the transfer function data. The fitting step specifically includes:

[0074] The starting point P1 for function fitting is determined as (n, 1+a), where [0, a] is the acceptable range of distortion rate, and n is the frequency corresponding to the transfer rate 1+a. When the value of the transfer function is 1, it indicates that the measurement system will not affect the authenticity of the test data, the test data is not distorted, and 1+a is the acceptable range of transfer rate. Optionally, if the error of multiple high-speed uniformity tests is δ, then a can take a value between [δ, 2δ]. Usually, the value of a is around 0.1.

[0075] The endpoint P2 of the function fitting is determined to be (250+f) rmax ,F(250+f rmax )), f rmax To cover the maximum rolling frequency for all test speeds and tire rolling circumferences, F(250+f) rmax () is a frequency of 250+f rmax Transmission rate, rolling frequency f r =V / C, where V is the test speed, C is the tire rolling circumference, and the rolling frequency f rThe value range of is generally [0,30]. Optionally, in order to maximize the applicable range of the fitted function and to facilitate the fitting process, the fitting endpoint P2 can be directly set to (300,F(300)).

[0076] At least 10 fitting points are taken every 100Hz starting from P1; optionally, the frequency intervals between each fitting point are equal.

[0077] After fitting the data of each transfer function, a univariate polynomial function equation of the transfer function is obtained. Usually, the transfer function exhibits an inverse parabolic shape within 300Hz. Therefore, the equation of the transfer function is usually a univariate quadratic function equation or a univariate cubic function equation. Data processing software can be used in the fitting process.

[0078] In some embodiments, the goodness-of-fit R-Sq value can be used as the criterion. The higher the goodness-of-fit, the better the fitting effect. Optionally, a goodness-of-fit R-Sq > 95% is considered to be effective. If it is lower than this standard, fitting points can be reselected and fitting can be performed again.

[0079] Another aspect of this application provides an application of the high-speed uniformity data correction method according to any of the above embodiments in tire cavity noise analysis. It can correct the distorted part of the non-uniform data obtained from the high-speed uniformity test, remove the limitation of the measurement system's inherent frequency on the test, and expand the observation range of tire cavity noise through high-speed uniformity data from 180Hz to 200Hz to 180Hz to 300Hz, thereby improving the utilization rate of existing equipment and avoiding the high cost of upgrading equipment.

[0080] The method for correcting high-speed uniformity data to analyze tire cavity noise includes the following steps:

[0081] The tire-rim assembly to be tested was tested using a high-speed homogeneity tester to obtain high-speed homogeneity data.

[0082] The high-speed uniformity data is corrected using the high-speed uniformity data correction method described in any of the above embodiments;

[0083] Based on the corrected high-speed uniformity data analysis, the amplitude abrupt change points are determined to identify the frequency, harmonic value, and risk of actual vehicle cavity noise.

[0084] The order of the above steps can be adjusted or two or more steps can be performed simultaneously, depending on the situation. For example, the transfer function of the existing high-speed uniformity measurement system can be obtained first using a high-speed uniformity data correction method. High-speed uniformity tests can then be conducted to obtain high-speed uniformity data for the tire-rim assembly. The obtained transfer function can then be used to correct the high-speed uniformity data, restoring distorted data to true data. Based on the corrected data, amplitude abrupt change points can be analyzed to determine the frequency of tire cavity noise. It is understandable that once the transfer function of the existing high-speed uniformity measurement system is obtained, subsequent cavity noise analysis does not require re-determining the transfer function; the known transfer function can be directly used for correction.

[0085] In some embodiments, the application further includes the step of establishing a predictive standard for the generation of actual vehicle cavity noise: selecting one or more tire sizes for subjective cavity noise testing, and obtaining the perceptible cavity noise harmonic value as a predictive standard based on the subjective cavity noise test results combined with corrected high-speed uniformity data; when the cavity noise harmonic value of the corrected high-speed uniformity data obtained in subsequent tests is equal to or greater than the established predictive standard, it is predicted that actual vehicle cavity noise will be generated.

[0086] In the above embodiments, a separate predictive standard can be established for each tire specification, or a single predictive standard can be established by summarizing the test results of multiple tire specifications, depending on different requirements and actual needs. The speed at which the cavity noise is perceptible to the driver and passengers is obtained based on subjective cavity noise testing, and the harmonic amplitude at the cavity frequency is used as the predictive standard in conjunction with high-speed uniformity data. When performing subsequent cavity noise analysis using high-speed uniformity data, if the harmonic value of the cavity noise is equal to or greater than the aforementioned predictive standard, it indicates that the actual vehicle is highly likely to also experience cavity noise that affects the driving experience. Therefore, the degree of adverse impact of tire cavity noise can be predicted without conducting subjective cavity noise testing.

[0087] Example 1

[0088] Establish the transfer function of existing high-speed uniformity equipment, such as Figure 6 As shown. During the fitting process, a = 0.1 was taken, and the fitting frequency range was 110–300 Hz. The functional equation for the transmissibility obtained from the fitting was: F(n) = -1.846 + 0.05339n - 0.000324n 2 +0.000001n 3 The goodness of fit R-Sq = 99.7%, indicating a valid fit.

[0089] A high-speed uniformity test was conducted on a tire with a specification of 205 / 55R16, and the high-speed uniformity data are shown in Table 1. The frequencies of each harmonic order at each speed were calculated according to formula (1), and the calculation results are shown in Table 2. The data in Tables 1 and 2 show that the non-uniformity harmonic values ​​are high in the relatively high frequency region (above 200Hz), and obvious distortion occurs.

[0090] Table 1 Original high-speed uniformity data

[0091]

[0092] Table 2. Frequency corresponding to high-speed uniformity data

[0093]

[0094] Divide the distorted data in Table 1 by the transmissivity at the corresponding frequency to correct the data. The corrected high-speed uniformity data is shown in Table 3.

[0095] Table 3. Corrected high-speed uniformity data

[0096]

[0097] Based on the data in Table 3, it can be determined that the corrected data shows a sudden change in harmonic values ​​at around 210Hz, and large values ​​appear at multiple speeds (e.g., 95, 100, and 115 km / h), exceeding the established prediction standard of 30N. It is predicted that the cavity noise in the actual vehicle will be relatively large, mainly occurring at speeds of 95, 100, and 115 km / h. The actual vehicle test feedback shows that the cavity noise is obvious at test speeds of around 95 to 110 km / h, which is consistent with the prediction results.

[0098] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0099] The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of the present invention or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the technical solutions claimed in the present invention.

Claims

1. A method for correcting high-speed uniformity data, characterized in that, Includes the following steps: The test object is installed at the shaft head of the high-speed uniformity equipment; An excitation is applied to the surface of the test object, and a first detection device for measuring the input signal is installed at the excitation position of the test object. A position different from the excitation position is selected as the output position, and a second detection device for measuring the output signal is installed at the output position. Establish a transfer function with the test frequency as the independent variable and the transfer rate as the dependent variable; where the transfer rate is the ratio of the Laplace transform of the output signal to the Laplace transform of the input signal, in dB. High-speed uniformity tests were conducted using the aforementioned high-speed uniformity equipment, and high-speed uniformity data were obtained. Calculate the frequencies at each harmonic order for each velocity in the high-speed uniformity data: f=V*n / (3.6*π*D) (1) In the formula, f is the frequency corresponding to a certain harmonic order at a certain speed, in Hz; V is the test speed of the high-speed uniformity test, in km / h; n is the harmonic order; and D is the outer diameter of the inflated tire, in meters. The transfer rate corresponding to each frequency f is obtained based on the transfer function; The high-speed uniformity data is divided by the transmissivity at the corresponding frequency to obtain the corrected high-speed uniformity data.

2. The method for correcting high-speed uniformity data according to claim 1, characterized in that, The test object is a tire-rim assembly or an annular substitute, wherein the annular substitute has a mass of 16-25 kg.

3. The method for correcting high-speed uniformity data according to claim 1, characterized in that, The output position is located on the surface of the test object opposite the excitation position.

4. The method for correcting high-speed uniformity data according to claim 1, characterized in that, The excitation direction is at least one of radial, lateral, and longitudinal.

5. The method for correcting high-speed uniformity data according to claim 1, characterized in that, The first detection device can measure the force and acceleration at the excitation position, and the second detection device can measure the force and acceleration at the output position. The input signal is the ratio of input acceleration to input force, and the output signal is the ratio of output acceleration to output force.

6. The method for correcting high-speed uniformity data according to claim 5, characterized in that, The steps for establishing the transfer function specifically include: Establish the frequency response function of the input signal and the frequency response function of the output signal: the frequency response function of the input signal has the test frequency as the independent variable and the input signal as the dependent variable; the frequency response function of the output signal has the test frequency as the independent variable and the output signal as the dependent variable. The ratio of the frequency response function of the output signal to the frequency response function of the input signal is the transfer function.

7. The method for correcting high-speed uniformity data according to claim 6, characterized in that, The step of establishing the transfer function also includes a step of fitting the data of the transfer function, the fitting step specifically including: The starting point P1 for function fitting is determined to be (n, 1+a), where [0, a] is the acceptable range of distortion rate, and n is the frequency corresponding to the transfer rate 1+a; The endpoint P2 of the function fitting is determined to be (250+f) rmax ,F(250+f rmax )), f rmax To cover the maximum rolling frequency for all test speeds and tire rolling circumferences, F(250+f) rmax () is a frequency of 250+f rmax Transmission rate, rolling frequency f r =V / C, where V is the test speed and C is the tire rolling circumference; Take at least 10 fitting points every 100Hz starting from P1; By fitting the data of each transfer function, a univariate polynomial function equation for the transfer function is obtained.

8. The method for correcting high-speed uniformity data according to claim 7, characterized in that, The goodness-of-fit R-Sq value is used as the criterion, and a goodness-of-fit R-Sq > 95% is considered to be effective.

9. The application of a method for correcting high-speed uniformity data according to any one of claims 1-8 in tire cavity noise analysis, characterized in that, Includes the following steps: The tire-rim assembly to be tested was tested using a high-speed homogeneity tester to obtain high-speed homogeneity data. The high-speed uniformity data is corrected using the high-speed uniformity data correction method as described in any one of claims 1-8; Based on the corrected high-speed uniformity data analysis, the amplitude abrupt change points are determined to identify the frequency, harmonic value, and risk of actual vehicle cavity noise.

10. The application according to claim 9, characterized in that, It also includes the step of establishing a predictive standard for the generation of actual vehicle cavity noise: selecting one or more tire sizes for subjective cavity noise testing, and based on the subjective cavity noise test results combined with the corrected high-speed uniformity data, obtaining the perceptible cavity noise harmonic value as the predictive standard; when the cavity noise harmonic value of the corrected high-speed uniformity data obtained in subsequent tests is equal to or greater than the established predictive standard, it is predicted that actual vehicle cavity noise will be generated.

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