Method for calculating damping loss factor curve of vehicle window glass

Abstract

The invention relates to a method for calculating a damping loss factor curve of vehicle window glass, which comprises the following steps: presetting a first set, a first element being a 1 / 3 octave frequency set; the peak points of the frequency response curves form a second set, the half-power bandwidth and the frequency bandwidth distance threshold value of each second element in the second set are obtained, and the second elements with the difference value between the half-power bandwidth and the frequency bandwidth distance threshold value not larger than 0 are selected to form a third set; performing deduplication and peak-free processing on the third elements in the third set, and forming a fourth set by the processed third elements; obtaining the corresponding first elements according to the frequencies of the fourth elements in the fourth sets, obtaining the minimum frequency value in the corresponding first elements, and obtaining a weight score; and obtaining fourth elements with the minimum weight fractions in the fourth set, wherein the fourth elements with the minimum weight fractions form a target peak point set. According to the method, standard selection of the peak points is realized through the algorithm, and the acquisition efficiency and accuracy of the peak points corresponding to the target frequency are improved.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle noise and vibration control, and in particular to a method for calculating a window glass damping loss factor curve. Background Art

[0002] The damping loss factor of car window glass is a parameter that measures the material's ability to absorb vibration energy and convert it into heat energy. For car window glass, improving its damping loss factor has the following potential benefits: Reduce noise: High damping materials can more effectively absorb the energy in sound waves, thereby reducing the noise level transmitted through the window to the cabin, which is very important for improving driving comfort and passenger experience; Improve vehicle NVH performance: NVH refers to noise, vibration and harshness. By using car window glass with higher damping characteristics, it can help improve the NVH performance of the entire vehicle, making the driving process smoother and quieter; Enhance safety: In the event of a collision, glass with good damping properties can better disperse the impact force and is not easy to break into sharp fragments, which helps protect the safety of people in the car; Extend service life: Good damping properties mean that the material is more resistant to fatigue damage under repeated stress, so it may help extend the service life of car window glass and other related components.

[0003] At present, when calculating the damping loss factor, the modal fitting method is to calculate the ratio of the half-power point bandwidth of the peak value of the response function (i.e., admittance) of the steady-state frequency of a single subsystem and the modal frequency corresponding to the peak value. The specific working principle is: use a suitable excitation device (such as a force hammer, a vibration table, etc.) to apply an excitation force to the structure to make the structure vibrate, and use a sensor (such as an accelerometer, etc.) to measure the response signal of the structure under excitation, and then determine the modal parameters through signal processing (such as fast Fourier transform, etc.) and modal parameter identification algorithm (such as frequency domain peak method, least square method, etc.). Among them, the frequency domain signal obtained after signal processing will form an obvious peak, and the frequency corresponding to these peaks is the natural frequency of the structure, but it is difficult to identify other modal parameters such as damping ratio and vibration mode, because the width of the frequency domain peak and other factors are related to the damping ratio, but it is difficult to accurately determine the damping ratio only through the frequency domain peak method; and the determination of the vibration mode requires the combination of the measurement results of multiple sensors at different positions and further calculations. The frequency domain peak method itself cannot directly provide complete vibration mode information. Moreover, the peak value selected by the frequency domain peak method is basically the maximum value within the frequency range corresponding to each test point, and more appropriate peak points will be ignored, resulting in the influence of the damping factor loss curve obtained by calculation, thereby affecting the analysis of the vehicle window glass. Summary of the invention

[0004] The invention provides a method for calculating a damping loss factor curve of a vehicle window glass, so as to solve the problem that the damping loss factor curve is affected due to non-standard peak selection, thereby affecting the analysis of the vehicle window glass.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A method for calculating a damping loss factor curve of a vehicle window glass comprises: S1: obtaining time domain response signals corresponding to a plurality of test points of the vehicle window glass respectively by a hammering method, and converting each time domain response signal into a corresponding frequency response curve; S2: determining a frequency interval according to a 1 / 3 octave, dividing each frequency response curve according to each frequency interval, and taking each frequency interval as a first element, and forming a first set by each first element; wherein each frequency interval is a continuous multi-segment frequency interval; defining a peak point of each frequency response curve as a second element, the second elements forming a second set, determining a frequency bandwidth distance threshold and a half-power bandwidth of each second element; selecting each second element whose difference between the half-power bandwidth and the frequency bandwidth distance threshold is not greater than 0, and defining it as a third element, the third element forming a second set; form a third set; S3: preprocess the third element in the third set, the preprocessed third element is defined as the fourth element, and each of the fourth elements constitutes a fourth set; S4: for each fourth element in the fourth set, determine the first element corresponding to the fourth element in the first set, and then determine the center frequency value in the first element, and obtain a weight score according to the half-power bandwidth of each fourth element and the frequency and the corresponding center frequency value; S5: obtain the fourth element with the smallest weight score according to each of the first elements, define each of the fourth elements with the smallest weight score as a target peak point, and each of the target peak points constitutes a target peak point set; S6: determine the damping loss factor according to each target peak point in the target peak point set, and draw a damping loss factor curve according to the damping loss factor.

[0007] According to the above technical means, by screening and processing the peak points layer by layer, it is avoided to waste computing resources on a large amount of irrelevant or inaccurate peak point data, and instead the target peak points that are most likely to represent the real damping characteristics of the car window are processed, thereby improving the calculation efficiency of the damping loss factor and reducing unnecessary computing time and cost waste;

[0008] First, the response signal of the window glass test point is obtained by hammering method and converted into a frequency response curve. This acquisition method is relatively simple and easy, and can quickly collect the original data related to the vibration characteristics of the window glass, laying a data foundation for the entire calculation process.

[0009] Then, the peak points of each frequency response curve are initially screened, and the frequencies corresponding to the frequency response curves are divided into multiple continuous frequency intervals to form the first set. This idea of ​​partitioning is helpful to analyze the relevant characteristics of window damping from the perspective of different frequency bands. Then, the peak points whose difference between the half-power bandwidth and the frequency bandwidth distance threshold is not greater than 0 are selected to form the third set. This screening method based on bandwidth characteristics can exclude some abnormal peak points that may be caused by interference factors such as noise or resolution, so that the peak points closely related to the inherent vibration characteristics of the window can be more accurately located; and the minimum frequency value in the corresponding first element is obtained according to the frequency of the fourth element in the fourth set (that is, the effective peak point after deduplication and peak-free processing) to calculate the weight score. This data processing method fully considers the distribution of peak points in the entire frequency interval. Through scientific weight allocation and comparison, the target peak point set can be determined more reasonably, avoiding the one-sided influence of a single factor or simple judgment on the peak point selection, making the entire data processing process more scientific and rigorous, thereby improving the reliability of the damping loss factor calculation;

[0010] Finally, the damping loss factor is calculated according to the target peak point in the target peak point set, and the damping loss factor curve is drawn and its corresponding frequency and amplitude are obtained, so that the obtained damping loss factor result can truly reflect the damping performance of the vehicle window glass under actual working conditions.

[0011] Furthermore, the frequency bandwidth distance threshold in S2 is obtained by the following steps: obtaining the corresponding first elements according to the frequencies of the second elements in each of the second sets, and obtaining the corresponding minimum frequency value and maximum frequency value of each of the first elements; and obtaining the frequency bandwidth distance threshold by combining the obtained minimum frequency value and maximum frequency value with the frequency bandwidth distance threshold algorithm.

[0012] According to the above technical means, the corresponding first element is determined according to the frequency of each second element in the second set, and then the minimum frequency value and the maximum frequency value of the first element are accurately obtained, and then calculated in combination with a special frequency bandwidth distance threshold algorithm. It provides a key quantitative standard for peak point screening from the dimension defined by the frequency interval.

[0013] Furthermore, the frequency bandwidth distance threshold algorithm is specifically:

[0014]

[0015] Wherein, L is the frequency bandwidth distance threshold, X i+1 is the maximum frequency value of the i-th element in the first set; X i is the minimum frequency value of the ith element in the first set, and γ is the preset peak width weight coefficient.

[0016] Furthermore, the half-power bandwidth in S2 is obtained by the following steps: obtaining the frequencies of the two half-power points corresponding to each of the second elements through a half-power formula, and obtaining the half-power bandwidth of each of the second elements according to the frequencies of the two half-power points.

[0017] According to the above technical means, the half-power bandwidth reflects the frequency range corresponding to the system when the energy is attenuated to half. It is closely related to the damping characteristics of the system and can show the characteristics of the peak point from the perspective of energy distribution. By comparing the half-power bandwidth and the frequency bandwidth distance threshold, the sharper peaks can be filtered out during the initial screening of the peak points in the second set, making the peak point data more representative, stable and reliable.

[0018] Furthermore, the calculation formula of the weight score is:

[0019] W=|(S i -F i )|×T1+(F2-F1)×T2,

[0020] Among them, W is the weight score, F i is the i-th element in the third set, S i is the intermediate frequency value of the i-th element in the first set, F2 and F1 correspond to the first half power point and the second half power point respectively, T1 is a preset first weight coefficient, and T2 is a preset second weight coefficient.

[0021] Furthermore, the preprocessing in S4 includes peak-free processing, and the peak-free processing specifically includes: for the Nth first element in the first set, obtaining the intermediate frequency value of the Nth first element, and determining the third elements corresponding to the Nth first element as the corresponding elements of the intermediate frequency value of the Nth first element; judging whether the Nth first element includes the corresponding elements, if the Nth first element does not include any of the corresponding elements, copying the third element corresponding to the N-1th first element, and defining the third element corresponding to the N-1th first element as the fourth element; wherein the first set is N continuous and successively increasing frequency intervals, and N is a positive integer not less than 1.

[0022] According to the above-mentioned technical means, by performing peak-free processing on each of the third elements, it is ensured that the minimum frequency value of each first element has a corresponding peak point, which effectively solves the problem of possible data gaps, so that the entire data set can remain relatively complete during the processing process, avoiding data gaps caused by the lack of corresponding peak points (third elements) in some intervals (frequency intervals corresponding to the first elements), and ensuring that the subsequent calculations, analysis and other work based on these data will not be hindered due to data missing, thereby improving the accuracy and reliability of the entire analysis work.

[0023] Furthermore, the S1 specifically includes: S11: obtaining the pulse signals of the acceleration and excitation force of each of the test points by a hammering method; S12: judging whether the excitation force can continuously obtain the same origin frequency response function curve at each of the test points. If the continuously generated origin frequency response function curves are consistent, then entering step S13; otherwise, returning to step S11 until the continuously generated origin frequency response function curves are consistent; S13: converting the acceleration signal into a frequency response curve and performing windowing processing. If there is no attenuation, it is necessary to increase the time constant of the exponential window function so that the attenuation degree of the acceleration signal meets the first preset value; if the attenuation of the acceleration signal exceeds the preset value, then reducing the The time constant of the exponential window function is set so that the attenuation degree of the acceleration signal meets the first preset value, then enters step S14; otherwise, returns to step S11 until the attenuation degree of the acceleration signal meets the first preset value; S14: ensure that the coherence function of the frequency response curve is greater than the second preset value, ensure that the coherence function of the frequency response curve is greater than the second preset value, if the coherence function of the frequency response curve is less than the second preset value, it is necessary to re-collect the time domain signal of the test point, and repeat steps S12-S14 until the origin frequency response function curve continuously generated by the excitation force signal is consistent, the attenuation degree of the acceleration signal meets the first preset value and the coherence function is greater than the second preset value.

[0024] According to the above technical means, by judging the frequency response curve converted from the excitation force and acceleration signal and the coherence function of the frequency response curve, the inspection and adjustment operations of multiple links such as signal acquisition, origin frequency response curve verification, and acceleration signal attenuation adjustment to the coherence function guarantee are realized. Each link cooperates with each other and checks at each level to form a rigorous closed-loop process, thereby ensuring to the greatest extent that the collected data and the subsequent signals processed based on these data are reliable, which is conducive to realizing standardized operations in actual vehicle window glass performance testing work, improving work efficiency and comparability of test results.

[0025] Furthermore, the damping loss factor calculated in S6 is obtained by the following steps: S61: according to the target peak point in the target set, obtaining the frequencies of the two half-power points corresponding to the target peak point; S62: obtaining the damping loss factor corresponding to the target peak point by combining the frequencies of the two half-power points and the frequency of the target peak point with the algorithm of the damping loss factor.

[0026] According to the above technical means, the calculation method of the damping loss factor at the half-power point is directly based on the frequency response characteristics of the system, without the need for complex mathematical models or additional testing equipment; and the damping loss factor calculated at the half-power point is calculated using multiple frequency point data in a continuous frequency band, which can reduce the error caused by single frequency point data and improve the accuracy of the test results.

[0027] Furthermore, the calculation formula of the damping loss factor is:

[0028]

[0029] Where η is the damping loss factor, F' i is the i-th target peak point in the target set, F2 and F1 are F' i The corresponding first half power point and second half power point.

[0030] Furthermore, an electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method described in any one of claims 1 to 9 when executing the program.

[0031] Beneficial effects of the present invention:

[0032] 1. By screening and processing all the peak points on each frequency response curve layer by layer, it avoids wasting computing resources on a large amount of irrelevant or inaccurate peak point data, and instead focuses on processing the target peak points that are most likely to represent the true damping characteristics of the window. Then, by improving the calculation efficiency of the damping loss factor of the peak points, unnecessary computing time and cost waste are reduced.

[0033] 2. Divide the frequencies corresponding to several frequency response curves into multiple continuous frequency intervals to form the first set. This partition analysis approach helps to analyze the damping-related characteristics of the window glass from the perspective of different frequency bands, and can more carefully grasp the performance rules under different frequency ranges, making the entire data analysis process more scientific and comprehensive, and meeting the requirements for in-depth exploration of complex physical properties.

[0034] 3. By comparing the difference between the half-power bandwidth and the frequency bandwidth distance threshold for initial screening, sharp peaks that may interfere with subsequent analysis can be effectively eliminated, and then qualified peak points are selected to form the third set. This screening method based on bandwidth characteristics can exclude some abnormal peak points that may be caused by noise or resolution interference factors, so that peak points closely related to the inherent vibration characteristics of the window can be located more accurately.

[0035] 4. By deduplicating and de-peaking the third set, this cleaning method eliminates abnormal or non-compliant peak data that may interfere with the final results, helps focus on the truly valuable key peaks that can accurately reflect the damping characteristics of the window glass, and further ensures the accuracy of the results.

[0036] 5. Determine the weight score based on the frequency of the elements in the fourth set and the corresponding minimum frequency value. This method of assigning weights based on the existing screened data and using reasonable mathematical logic can objectively measure the importance of different elements in the final calculation, providing a scientific basis for accurately locating key target peaks. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of a specific implementation process of the present invention;

[0038] Figure 2 It is a flow chart of the non-peak processing of the present invention;

[0039] Figure 3 This is a data collection flow chart of the present invention;

[0040] Figure 4 It is a schematic diagram of the specific implementation process of the damping loss factor of the present invention.

[0041] The drawings are only used for illustrative purposes and should not be construed as limitations on this patent. In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. The same or similar numbers correspond to the same or similar parts. The terms describing the positional relationship in the drawings are only used for illustrative purposes and should not be construed as limitations on this patent. DETAILED DESCRIPTION

[0042] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0043] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0044] In the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0045] In the embodiments of the present application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0046] In the embodiments of the present application, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0047] The present invention provides a method for calculating the damping loss factor curve of a vehicle window glass, such as Figure 1As shown, it includes: S1: obtaining time domain response signals corresponding to several test points of the vehicle window glass respectively by a hammering method, and converting each time domain response signal into a corresponding frequency response curve; S2: determining the frequency interval according to 1 / 3 octave, dividing each frequency response curve according to each frequency interval, and taking each frequency interval as the first element, and forming a first set by each first element; wherein each frequency interval is a continuous multi-segment frequency interval; defining the peak point of each frequency response curve as the second element, the second elements forming a second set, determining the frequency bandwidth distance threshold and half-power bandwidth of each second element; selecting each second element whose difference between the half-power bandwidth and the frequency bandwidth distance threshold is not greater than 0, and defining it as the third element, and the third elements forming a third set; S3: The third elements in the three sets are preprocessed, and the preprocessed third elements are defined as fourth elements, and the fourth elements constitute a fourth set; S4: For each fourth element in the fourth set, in the first set, determine the first element corresponding to the fourth element, and then determine the center frequency value in the first element, and obtain a weight score according to the half-power bandwidth of each fourth element and the frequency and the corresponding center frequency value; S5: According to each first element, obtain the fourth element with the smallest weight score, define each fourth element with the smallest weight score as a target peak point, and each target peak point constitutes a target peak point set; S6: According to each target peak point in the target peak point set, determine the damping loss factor, and draw a damping loss factor curve according to the damping loss factor.

[0048] Preferably, the frequency interval in step S2 is obtained by the following steps: defining an intermediate frequency value, which is specifically 1000 Hz, and obtaining the intermediate frequency value corresponding to each frequency interval through the intermediate frequency value calculation formula according to the intermediate frequency value; then obtaining the frequency interval corresponding to each intermediate frequency value through the frequency interval calculation formula according to each intermediate frequency value; each frequency interval divides the frequencies corresponding to a number of frequency response curves into a continuous plurality of frequency intervals, and defines each frequency interval as a first element, and each first element constitutes a first set.

[0049] Preferably, the calculation formula of the intermediate frequency value is:

[0050] Intermediate frequency value greater than 1000Hz: f n+1 =2 a ×f n ; Intermediate frequency value less than 1000Hz: Among them, f n is the preset intermediate frequency value, f n-1 and f n+1 f n The corresponding adjacent intermediate frequency value, a is the preset frequency range.

[0051] Specifically, the frequency interval is calculated as follows: The upper limit frequency of the frequency interval: The lower limit frequency of the frequency interval: Among them, f n is the intermediate frequency value, f l is the minimum frequency value of the frequency interval corresponding to the intermediate frequency value, f u is the maximum frequency value of the frequency interval corresponding to the intermediate frequency value, and a is the preset frequency range.

[0052] More preferably, the intermediate frequency value and the upper and lower limit frequencies of the frequency interval are all integer values.

[0053] The present invention avoids wasting computing resources on a large amount of irrelevant or inaccurate peak point data by screening and processing the peak points layer by layer in a targeted manner, and instead focuses on processing the target peak points that are most likely to represent the real damping characteristics of the vehicle window, thereby improving the calculation efficiency of the damping loss factor and reducing unnecessary computing time and cost waste;

[0054] First, the response signal of the window glass test point is obtained by hammering method and converted into a frequency response curve. This acquisition method is relatively simple and easy, and can quickly collect the original data related to the vibration characteristics of the window glass, laying a data foundation for the entire calculation process.

[0055] Then, the peak points of each frequency response curve are initially screened, and the frequencies corresponding to the frequency response curves are divided into multiple continuous frequency intervals to form the first set. This idea of ​​partitioning is helpful to analyze the relevant characteristics of window damping from the perspective of different frequency bands. Then, the peak points whose difference between the half-power bandwidth and the frequency bandwidth distance threshold is not greater than 0 are selected to form the third set. This screening method based on bandwidth characteristics can exclude some abnormal peak points that may be caused by interference factors such as noise or resolution, so that the peak points closely related to the inherent vibration characteristics of the window can be more accurately located; and the minimum frequency value in the corresponding first element is obtained according to the frequency of the fourth element in the fourth set (that is, the effective peak point after deduplication and peak-free processing) to calculate the weight score. This data processing method fully considers the distribution of peak points in the entire frequency interval. Through scientific weight allocation and comparison, the target peak point set can be determined more reasonably, avoiding the one-sided influence of a single factor or simple judgment on the peak point selection, making the entire data processing process more scientific and rigorous, thereby improving the reliability of the damping loss factor calculation;

[0056] Finally, the damping loss factor is calculated according to the target peak point in the target peak point set, and the damping loss factor curve is drawn and its corresponding frequency and amplitude are obtained, so that the obtained damping loss factor result can truly reflect the damping performance of the vehicle window glass under actual working conditions.

[0057] In this embodiment, the frequency bandwidth distance threshold in S2 is obtained by the following steps: obtaining the corresponding first elements according to the frequencies of the second elements in each second set, and obtaining the minimum frequency value and the maximum frequency value of the corresponding first elements; and obtaining the frequency bandwidth distance threshold by combining the obtained minimum frequency value and the maximum frequency value with the frequency bandwidth distance threshold algorithm.

[0058] The corresponding first element is determined according to the frequency of each second element in the second set, and then the minimum frequency value and the maximum frequency value of the first element are accurately obtained, and then calculated in combination with a special frequency bandwidth distance threshold algorithm. It provides a key quantitative standard for peak point screening from the dimension defined by the frequency interval.

[0059] In this embodiment, the frequency bandwidth distance threshold algorithm is specifically:

[0060]

[0061] Where L is the frequency bandwidth distance threshold, X i+1 is the maximum frequency value of the i-th element in the first set; X i is the minimum frequency value of the ith element in the first set, and γ is the preset peak width weight coefficient.

[0062] In this embodiment, the half-power bandwidth in S2 is obtained by the following steps: obtaining the frequencies of the two half-power points corresponding to each second element through the half-power formula, and obtaining the half-power bandwidth of each second element according to the frequencies of the two half-power points.

[0063] The half-power bandwidth reflects the frequency range corresponding to the system when the energy is attenuated to half. It is closely related to the damping characteristics of the system and can show the characteristics of the peak point from the perspective of energy distribution. By comparing the half-power bandwidth and the frequency bandwidth distance threshold, the sharper peaks can be filtered out during the initial screening of the peak points in the second set, making the peak point data more representative, stable and reliable.

[0064] In this embodiment, the calculation formula of the weight score is:

[0065] W=|(S i -F i )|×T1+(F2-F1)×T2;

[0066] Among them, W is the weight score, F i is the i-th element in the third set, S i is the intermediate frequency value of the i-th element in the first set, F2 and F1 correspond to the first half power point and the second half power point respectively, T1 is a preset first weight coefficient, and T2 is a preset second weight coefficient.

[0067] like Figure 2 As shown, in this embodiment, preprocessing 1 in S4 includes peak-free processing, and the peak-free processing specifically includes: for the Nth first element in the first set, obtaining the intermediate frequency value of the Nth first element, and determining the third elements corresponding to the Nth first element as the corresponding elements of the intermediate frequency value of the Nth first element; judging whether the Nth first element includes the corresponding elements, if the Nth first element does not include any of the corresponding elements, copying the third element corresponding to the N-1th first element, and defining the third element corresponding to the N-1th first element as the fourth element; wherein the first set is N continuous and successively increasing frequency intervals, and N is a positive integer not less than 1.

[0068] By performing peak-free processing on each third element and ensuring that the minimum frequency value of each first element has a corresponding peak point, the problem of possible data gaps is effectively solved, so that the entire data set can remain relatively complete during the processing process, avoiding data gaps caused by the lack of corresponding peak points (third elements) in some intervals (frequency intervals corresponding to the first elements), and ensuring that subsequent calculations, analyses, and other work based on these data will not be hindered by missing data, thereby improving the accuracy and reliability of the entire analysis work.

[0069] like Figure 3 As shown, in this embodiment, S1 specifically includes: S11: obtaining the pulse signal of the acceleration and excitation force of each test point by the hammer method; S12: judging whether the excitation force can continuously obtain the same origin frequency response function curve at each test point, if the continuously generated origin frequency response function curves are consistent, then entering step S13; otherwise, returning to step S11 until the continuously generated origin frequency response function curves are consistent; S13: converting the acceleration signal into a frequency response curve and performing windowing processing, if there is no attenuation, it is necessary to increase the time constant of the exponential window function so that the attenuation degree of the acceleration signal meets the first preset value; if the attenuation of the acceleration signal exceeds the preset value, then Reduce the time constant of the exponential window function so that the attenuation degree of the acceleration signal meets the first preset value, and then enter step S14; otherwise, return to step S11 until the attenuation degree of the acceleration signal meets the first preset value; S14: ensure that the coherence function of the frequency response curve is greater than the second preset value, ensure that the coherence function of the frequency response curve is greater than the second preset value. If the coherence function of the frequency response curve is less than the second preset value, it is necessary to re-collect the time domain signal of the test point, and repeat steps S12-S14 until the origin frequency response function curve continuously generated by the excitation force signal is consistent, the attenuation degree of the acceleration signal meets the first preset value and the coherence function is greater than the second preset value.

[0070] In the actual test process, the position of the test point needs to reflect the vibration mode corresponding to all elements in the first set. Therefore, during the test, 2 to 6 acceleration sensors are usually arranged according to the size of the window glass, and the acceleration sensors are installed on the outer surface of the window and fixed with a suitable adhesive; and for consistency, the sensor direction arrangement adopts a unified vehicle coordinate system, such as: taking the driver's seat as the origin, along the length direction of the vehicle body and backward is the positive direction of the X direction, along the width direction of the vehicle body and toward the co-pilot seat is the positive direction of the Y direction, and along the height direction of the vehicle body and upward is the positive direction of the Z direction.

[0071] By judging the frequency response curve converted from the excitation force and acceleration signal and the coherence function of the frequency response curve, the inspection and adjustment operations of multiple links including signal acquisition, origin frequency response curve verification, and acceleration signal attenuation adjustment to coherence function guarantee are realized. Each link cooperates with each other and checks at each level to form a rigorous closed-loop process, thereby ensuring to the greatest extent that the collected data and the subsequent signals processed based on these data are reliable, which is conducive to realizing standardized operations in actual vehicle window glass performance testing work, improving work efficiency and the comparability of test results.

[0072] like Figure 4 As shown, in this embodiment, the damping loss factor calculated in S6 is obtained by the following steps: S61: According to the target peak point in the target set, the frequencies of the two half-power points corresponding to the target peak point are obtained; S62: Through the frequencies of the two half-power points and the frequency of the target peak point, combined with the algorithm of the damping loss factor, the damping loss factor corresponding to the target peak point is obtained.

[0073] The calculation method of the damping loss factor at the half-power point is directly based on the frequency response characteristics of the system, without the need for complex mathematical models or additional test equipment. The damping loss factor at the half-power point is calculated using multiple frequency point data in a continuous frequency band, which can reduce the error caused by single frequency point data and improve the accuracy of the test results.

[0074] In this embodiment, the calculation formula of the damping loss factor is:

[0075] Where η is the damping loss factor, F i ′ is the i-th target peak point in the target set, and F2 and F1 are F i ′ The corresponding first half power point and second half power point.

[0076] This embodiment also relates to an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method described in any one of claims 2 to 6 when executing the program.

[0077] In summary, a method for calculating a damping loss factor curve of a vehicle window glass comprises the following steps:

[0078] S1: Obtain the time domain response signals of several test points of the vehicle window glass by hammering method, and judge whether the origin frequency response function curves continuously generated by the excitation force signal in the time domain signal are consistent, whether the attenuation degree of the acceleration signal meets the first preset value and whether the coherence function is greater than the second preset value. If all the conditions are met, then enter step S2; otherwise, it is necessary to re-acquire the time domain response signal until the excitation force signal, the acceleration signal and the coherence function meet the above conditions;

[0079] S2: Define an intermediate frequency value, which is specifically 1000 Hz. According to the intermediate frequency value, the intermediate frequency value corresponding to each frequency interval is obtained by the intermediate frequency value calculation formula; then according to each intermediate frequency value, the frequency interval corresponding to each intermediate frequency value is obtained by the frequency interval calculation formula; each frequency interval divides the frequencies corresponding to several frequency response curves into multiple continuous frequency intervals, and each frequency interval is defined as the first element, and each first element constitutes a first set.

[0080] The peak point of each frequency response curve is defined as the second element, the second elements constitute a second set, the frequency bandwidth distance threshold and the half-power bandwidth of each second element are determined, and each second element whose difference between the half-power bandwidth and the frequency bandwidth distance threshold is not greater than 0 is defined as the third element, and the third elements constitute a third set;

[0081] S3: Obtain the corresponding first elements according to the frequencies of the third elements in each third set, and obtain the minimum frequency value and the maximum frequency value of the corresponding first elements, respectively select the third element near the minimum frequency value and the third element near the maximum frequency value, perform peakless processing on the third elements corresponding to the minimum frequency value and the maximum frequency value, and define the processed third elements as fourth elements, and the fourth elements constitute a fourth set;

[0082] S4: for each fourth element in the fourth set, determine the first element corresponding to the fourth element in the first set, further determine the intermediate frequency value in the first element, and obtain a weight score according to the frequency of each fourth element and the corresponding intermediate frequency value;

[0083] S5: Obtain the fourth element with the smallest weight score according to each first element, define each fourth element with the smallest weight score as a target peak point, and each target peak point constitutes a target peak point set;

[0084] S6: Determine a damping loss factor according to each target peak point in the target peak point set, and draw a damping loss factor curve according to the damping loss factor.

[0085] The above embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Any equivalent substitution or change made by a person skilled in the art based on the present invention is within the protection scope of the present invention.

Claims

1. A method for calculating a damping loss factor curve of a vehicle window glass, characterized in that: The following steps are involved: S1: Obtain the time domain response signals corresponding to several test points of the vehicle window glass by hammering method, and convert each time domain response signal into a corresponding frequency response curve; S2: determining a frequency interval according to a 1 / 3 octave, dividing each frequency response curve according to each frequency interval, and taking each frequency interval as a first element, and forming a first set by each first element; wherein each frequency interval is a continuous multiple frequency interval; Define the peak point of each frequency response curve as a second element, the second elements constitute a second set, determine the frequency bandwidth distance threshold and the half-power bandwidth of each second element; select each second element whose difference between the half-power bandwidth and the frequency bandwidth distance threshold is not greater than 0, and define it as a third element, the third elements constitute a third set; S3: preprocessing the third elements in the third set, defining the preprocessed third elements as fourth elements, and each of the fourth elements constitutes a fourth set; S4: for each fourth element in the fourth set, determine the first element corresponding to the fourth element in the first set, and then determine the center frequency value in the first element, and obtain a weight score according to the half-power bandwidth of each fourth element and the frequency and the corresponding center frequency value; S5: acquiring a fourth element with the smallest weight score according to each of the first elements, defining each of the fourth elements with the smallest weight score as a target peak point, and each of the target peak points constitutes a target peak point set; S6: Determine a damping loss factor according to each target peak point in the target peak point set, and draw a damping loss factor curve according to the damping loss factor.

2. The method for calculating the damping loss factor curve of vehicle window glass according to claim 1, characterized in that: The frequency bandwidth distance threshold in S2 is obtained by the following steps: Obtaining the corresponding first elements according to the frequencies of the second elements in the second sets, and obtaining the minimum frequency value and the maximum frequency value of the corresponding first elements; The obtained minimum frequency value and maximum frequency value are combined with the frequency bandwidth distance threshold algorithm to obtain the frequency bandwidth distance threshold.

3. The method for calculating the damping loss factor curve of vehicle window glass according to claim 2, characterized in that: The frequency bandwidth distance threshold algorithm is specifically: Wherein, L is the frequency bandwidth distance threshold, X i+1 is the maximum frequency value of the i-th element in the first set; X i is the minimum frequency value of the ith element in the first set, and γ is the preset peak width weight coefficient.

4. The method for calculating the damping loss factor curve of vehicle window glass according to claim 3, characterized in that: The half-power bandwidth in S2 is obtained by the following steps: obtaining the frequencies of the two half-power points corresponding to each of the second elements through the half-power formula, and obtaining the half-power bandwidth of each of the second elements according to the frequencies of the two half-power points.

5. The method for calculating the damping loss factor curve of vehicle window glass according to claim 1, characterized in that: The calculation formula of the weight score is: W=|(S i -F i )|×T1+(F2-F1)×T2; Among them, W is the weight score, F i is the i-th element in the third set, S i is the middle frequency value of the i-th element in the first set, and F2 and F1 are F i Corresponding to the first half power point and the second half power point, T1 is a preset first weight coefficient, and T2 is a preset second weight coefficient.

6. The method for calculating the damping loss factor curve of vehicle window glass according to claim 1, characterized in that: The preprocessing in S3 includes peak-free processing, and the peak-free processing specifically includes: For an Nth first element in the first set, obtain an intermediate frequency value of the Nth first element, and determine the third elements corresponding to the Nth first element as the corresponding elements of the intermediate frequency value of the Nth first element; Determine whether the Nth first element includes the corresponding elements; if the Nth first element does not include any of the corresponding elements, copy the third element corresponding to the N-1th first element, and define the third element corresponding to the N-1th first element as the fourth element; wherein the first set is N continuous and sequentially increasing frequency intervals, and N is a positive integer not less than 1.

7. The method for calculating the damping loss factor curve of vehicle window glass according to claim 1, characterized in that: The S1 specifically includes: S11: Obtaining the pulse signals of acceleration and excitation force of each test point by hammering method; S12: judging whether the excitation force can continuously obtain the same origin frequency response function curve at each test point, if the continuously generated origin frequency response function curves are consistent, proceeding to step S13; otherwise, returning to step S11 until the continuously generated origin frequency response function curves are consistent; S13: converting the acceleration signal into a frequency response curve and performing windowing processing. If there is no attenuation, it is necessary to increase the time constant of the exponential window function so that the attenuation degree of the acceleration signal meets the first preset value; if the attenuation of the acceleration signal exceeds the preset value, the time constant of the exponential window function is reduced so that the attenuation degree of the acceleration signal meets the first preset value, and then enter step S14; otherwise, return to step S11 until the attenuation degree of the acceleration signal meets the first preset value; S14: Ensure that the coherence function of the frequency response curve is greater than a second preset value. If the coherence function of the frequency response curve is less than the second preset value, it is necessary to re-collect the time domain signal of the test point and repeat steps S12-S14 until the origin frequency response function curve continuously generated by the excitation force signal is consistent, the attenuation degree of the acceleration signal satisfies the first preset value and the coherence function is greater than the second preset value.

8. The method for calculating the damping loss factor curve of vehicle window glass according to claim 1, characterized in that: The damping loss factor calculated in S6 is obtained by the following steps: S61: acquiring frequencies of two half-power points corresponding to the target peak point in the target set; S62: Obtain the damping loss factor corresponding to the target peak point by combining the frequencies of the two half-power points and the frequency of the target peak point with an algorithm of the damping loss factor.

9. The method for calculating the damping loss factor curve of vehicle window glass according to claim 8, characterized in that: The calculation formula of the damping loss factor is: Where η is the damping loss factor, F i ′ is the i-th target peak point in the target set, and F2 and F1 are F i ′ The corresponding first half power point and second half power point.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the method according to any one of claims 1 to 9 is implemented.

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