Method and device for identifying a low-frequency dithering excitation source based on a test process

Abstract

The application relates to a low-frequency dithering excitation source identification method and device based on a test process. The method comprises the following steps: performing a road test on a to-be-tested vehicle under a target working condition; acquiring time-domain vibration data of a target test point and external parameter information of the to-be-tested vehicle through a test module arranged at the target test point of the to-be-tested vehicle; analyzing whether a tire excitation source of the to-be-tested vehicle is a vehicle dithering excitation source; if the tire excitation source of the to-be-tested vehicle is the vehicle dithering excitation source, acquiring first dithering vibration mode information of the to-be-tested vehicle; performing a bench test on the to-be-tested vehicle; acquiring second dithering vibration mode information of low-frequency excitation signals input at different tire excitation positions of the to-be-tested vehicle during the bench test; and determining the position of the tire excitation source of the to-be-tested vehicle. The method can effectively identify the specific tire position when the dithering reason of the vehicle comes from the tire excitation exceeding the standard.

Description

Technical Field

[0001] This application relates to the field of vehicle NVH testing technology, and in particular to a method and device for identifying low-frequency vibration excitation sources based on the testing process. Background Technology

[0002] During vehicle operation, driving and steering forces are generated through the interaction between the tires and the ground. As the tires rotate, they inevitably experience periodic vertical excitation due to factors such as radial non-roundness, dynamic imbalance, and differences in radial stiffness. This excitation is further transmitted to the chassis or body via the axle, ultimately being perceived by the customer. When the excitation force exceeds a certain limit, user complaints are inevitable; therefore, it is necessary to identify the causes of vehicle vibration.

[0003] Traditional technologies primarily rely on various testing methods to determine the cause of vehicle vibration. For example, sequentially testing the engine, clutch, transmission, driveshaft, and wheel assembly can help identify the cause of vehicle vibration. However, this method has a drawback: if a problem is detected in the wheel assembly, it only indicates that the vibration originates from the wheel assembly, and excessive tire excitation at different locations will result in different vibration patterns and characteristics.

[0004] The above-mentioned detection methods are not easy to identify specific tire positions in a timely and effective manner. Therefore, it is not easy to obtain accurate results for tires in different positions that exceed the excitation limit. Summary of the Invention

[0005] Therefore, it is necessary to provide a method and device for identifying low-frequency vibration excitation sources based on the test process to address the above-mentioned technical problems. This method and device can identify the specific tire position in a timely and effective manner when the vibration of a vehicle is caused by excessive tire excitation.

[0006] Firstly, this application provides a method for identifying low-frequency jitter excitation sources based on the experimental process.

[0007] The method includes:

[0008] Under target operating conditions, a road test is conducted on the vehicle under test. The test module is arranged at the target test point of the vehicle under test to obtain the time-domain vibration data of the target test point and the external parameter information of the vehicle under test.

[0009] Based on the time-domain vibration data, analyze whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source;

[0010] If the tire excitation source of the vehicle under test is the vehicle vibration excitation source, then the first vibration mode information of the vehicle under test is obtained based on the time-domain vibration data.

[0011] Based on the external parameter information of the vehicle under test, a bench test is conducted on the vehicle under test;

[0012] Acquire the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test during the bench test;

[0013] The location of the tire excitation source of the vehicle under test is determined based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

[0014] In one embodiment, analyzing whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source based on the time-domain vibration data includes:

[0015] Based on the time-domain vibration data, obtain the target test point frequency information and tire rolling excitation frequency information of the vehicle under test;

[0016] By comparing the frequency information of the target test point with the tire rolling excitation frequency information, the frequency difference is obtained;

[0017] If the frequency difference is within a preset frequency threshold range, then the tire excitation source of the vehicle under test is determined to be the vehicle vibration excitation source.

[0018] In one embodiment, the different tire excitation positions include: full-wheel excitation, rear four-wheel excitation, front two-wheel excitation, left and right side reverse phase excitation, rear four-wheel left and right reverse phase excitation, rear four-wheel front and rear reverse phase excitation, and rear four-wheel diagonal same phase excitation.

[0019] The input low-frequency excitation signal includes a sinusoidal signal with an equal time-domain rate of change from 0 to 20 Hz.

[0020] In one embodiment, acquiring the second jitter vibration mode information of the low-frequency excitation signal input to the vehicle under test at different tire excitation positions during the bench test includes:

[0021] Acquire acceleration and displacement information at each tire excitation location of the vehicle under test;

[0022] Based on the acceleration and displacement information of each tire excitation position, the second vibration spectrum at each tire excitation position in the bench test is obtained.

[0023] Based on the second vibration spectrum at each tire excitation position during the bench test, the second jitter vibration mode information of the low-frequency excitation signal input to the vehicle under test at each tire excitation position is obtained by analysis.

[0024] In one embodiment, determining the location of the tire excitation source of the vehicle under test based on the first vibration morphology information and the second vibration morphology information at different tire excitation locations includes:

[0025] Based on the first shaking vibration pattern information, the first vibration spectrum under the target working condition in the road test is obtained;

[0026] The first vibration spectrum is matched with the second vibration spectrum at different tire excitation positions in the bench test to obtain the pre-selected tire excitation positions that meet the preset conditions.

[0027] The location of the tire excitation source of the vehicle under test is determined based on the pre-selected tire excitation location, the first vibration pattern information, and the second vibration pattern information of different tire excitation locations.

[0028] In one embodiment, the external parameter information of the vehicle under test includes the mass load information of the driver and passenger seats, as well as the mass and position information of the test module; correspondingly,

[0029] The step of conducting bench tests on the vehicle under test based on the external parameter information of the vehicle under test includes:

[0030] Each tire of the vehicle under test is equipped with a vibration table with an individual excitation source;

[0031] The same mass load is applied to the driver and passenger seats, and the test modules placed at the target test points are kept to have the same mass and remain in the same position.

[0032] A bench test is conducted by inputting a continuous low-frequency excitation signal at different tire excitation positions of the vehicle under test using a vibration table.

[0033] Secondly, this application also provides a low-frequency jitter excitation source identification device based on the experimental process. The device includes:

[0034] The test module is set up at the target test point of the vehicle under test during the road test to test the time-domain vibration data at the target test point under the target operating conditions.

[0035] The acquisition module is used to acquire time-domain vibration data of the target test point, as well as external parameter information of the vehicle under test;

[0036] The judgment module is used to determine whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source based on the time-domain vibration data.

[0037] The acquisition module is also used to acquire the first vibration mode information of the vehicle under test based on the time-domain vibration data when the tire excitation source of the vehicle under test is the vehicle vibration excitation source.

[0038] The processing module is used to perform bench tests on the vehicle under test when the tire excitation source of the vehicle under test is used as the vehicle vibration excitation source, based on the external parameter information of the vehicle under test and the test module arranged at the target test point of the vehicle under test.

[0039] A vibration table is used to input low-frequency excitation signals at different tire excitation positions of the vehicle under test.

[0040] The acquisition module is also used to acquire the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test;

[0041] The processing module is also used to determine the location of the tire excitation source of the vehicle under test based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

[0042] Thirdly, this application also provides a computer device. The computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to perform the following steps:

[0043] Under target operating conditions, a road test is conducted on the vehicle under test. The test module is arranged at the target test point of the vehicle under test to obtain the time-domain vibration data of the target test point and the external parameter information of the vehicle under test.

[0044] Based on the time-domain vibration data, analyze whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source;

[0045] If the tire excitation source of the vehicle under test is the vehicle vibration excitation source, then the first vibration mode information of the vehicle under test is obtained based on the time-domain vibration data.

[0046] Based on the external parameter information of the vehicle under test, a bench test is conducted on the vehicle under test;

[0047] Acquire the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test during the bench test;

[0048] The location of the tire excitation source of the vehicle under test is determined based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

[0049] Fourthly, this application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, performs the following steps:

[0050] Under target operating conditions, a road test is conducted on the vehicle under test. The test module is arranged at the target test point of the vehicle under test to obtain the time-domain vibration data of the target test point and the external parameter information of the vehicle under test.

[0051] Based on the time-domain vibration data, analyze whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source;

[0052] If the tire excitation source of the vehicle under test is the vehicle vibration excitation source, then the first vibration mode information of the vehicle under test is obtained based on the time-domain vibration data.

[0053] Based on the external parameter information of the vehicle under test, a bench test is conducted on the vehicle under test;

[0054] Acquire the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test during the bench test;

[0055] The location of the tire excitation source of the vehicle under test is determined based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

[0056] Fifthly, this application also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, performs the following steps:

[0057] Under target operating conditions, a road test is conducted on the vehicle under test. The test module is arranged at the target test point of the vehicle under test to obtain the time-domain vibration data of the target test point and the external parameter information of the vehicle under test.

[0058] Based on the time-domain vibration data, analyze whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source;

[0059] If the tire excitation source of the vehicle under test is the vehicle vibration excitation source, then the first vibration mode information of the vehicle under test is obtained based on the time-domain vibration data.

[0060] Based on the external parameter information of the vehicle under test, a bench test is conducted on the vehicle under test;

[0061] Acquire the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test during the bench test;

[0062] The location of the tire excitation source of the vehicle under test is determined based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

[0063] The above-mentioned method and apparatus for identifying low-frequency jitter excitation sources based on the experimental process have the following technical advantages:

[0064] 1. In road tests, the time-domain vibration data obtained through the testing module can determine that excessive tire excitation is the cause of vehicle vibration. Then, bench tests are conducted. During the bench tests, low-frequency excitation is applied to different tire excitation positions of the vehicle under test. By comparing the vibration patterns at different excitation positions in the bench tests with those in the road tests, the specific tire excitation position can be determined. This method can accurately pinpoint the tire location causing vehicle vibration, enabling staff to quickly identify tire faults and take appropriate measures.

[0065] 2. The amplitude of the tire can be controlled at different positions by inputting a sinusoidal signal with a continuously changing rate of change in the time domain.

[0066] 3. By applying the same mass load to the driver and passenger sides of the vehicle under test, and by keeping the mass of the test modules the same and their positions unchanged, the boundary conditions of the bench test and the road test are made consistent. Attached Figure Description

[0067] Figure 1 This is an application environment diagram of a low-frequency jitter excitation source identification method based on the experimental process in one embodiment;

[0068] Figure 2 This is a flowchart illustrating a low-frequency jitter excitation source identification method based on an experimental process in one embodiment;

[0069] Figure 3 This is a vibration spectrum diagram of a vehicle under test during a road test in one embodiment.

[0070] Figure 4 This is a schematic diagram of a bench test performed on the vehicle under test in one embodiment;

[0071] Figure 5 This is a schematic diagram illustrating the unfolding process of step S210 in one embodiment;

[0072] Figure 6 This is an example diagram of a low-frequency excitation signal used in a bench test of a vehicle under test in one embodiment.

[0073] Figure 7 This is a vibration spectrum diagram of the excitation positions of the rear four tires of the vehicle under test during a bench test in one embodiment.

[0074] Figure 8 This is a schematic diagram of the arrangement of the vibration table for bench testing of the vehicle under test in one embodiment.

[0075] Figure 9This is a schematic diagram of a device for identifying low-frequency jitter excitation sources based on an experimental process in one embodiment;

[0076] Figure 10 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0077] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0078] The low-frequency jitter excitation source identification method based on the experimental process provided in this application embodiment can be applied to, for example... Figure 1 In the application environment shown, terminal 102 communicates with server 104 via a network. The data storage system can store time-domain vibration data, external parameter information, etc., that server 104 needs to process. The data storage system can be integrated on server 104 or placed on the cloud or other network servers. Server 104 obtains time-domain vibration data of the target test point and external parameter information of the vehicle under test through the test module, and analyzes whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source. If the tire excitation source of the vehicle under test is a vehicle vibration excitation source, it obtains the first vibration mode information of the vehicle under test based on the time-domain vibration data; then it obtains the second vibration mode information of the low-frequency excitation signals input at different tire excitation positions of the vehicle under test during the bench test; based on the first vibration mode information and the second vibration mode information at different tire excitation positions, it determines the position of the tire excitation source of the vehicle under test. Terminal 102 can be, but is not limited to, various personal computers, laptops, smartphones, tablets, IoT devices, and portable wearable devices. IoT devices can be smart speakers, smart TVs, smart air conditioners, smart vehicle devices, etc. Portable wearable devices can include smartwatches, smart bracelets, and head-mounted devices. Server 104 can be implemented using a standalone server or a server cluster consisting of multiple servers.

[0079] In one embodiment, such as Figure 2 As shown, a method for identifying low-frequency jitter excitation sources based on the experimental process is provided, and this method is applied to... Figure 1 Taking server 104 as an example, the following steps are included:

[0080] Step S202: Under target operating conditions, conduct road tests on the vehicle under test. By using test modules placed at the target test points of the vehicle under test, acquire time-domain vibration data of the target test points and external parameter information of the vehicle under test.

[0081] Optionally, the vehicle under test used in this embodiment is a 6x4 tractor unit with three axles (i.e., six wheels). The target test points are the eight vertices of the cab, distributed on the left and right sides of the chassis, the left and right sides of the chassis, and the axle ends on both sides of the three axles. The test module consists of multiple triaxial acceleration sensors, one at each of the eight vertices of the cab, one on each of the left and right sides of the chassis, and one on each side of the axle ends of the three axles. To correspond to subjective perception, an additional target test point is added at the driver's seat rail. A custom three-axis coordinate system is defined, with the starting point generally set at the front end of the vehicle under test. The geometric coordinates of each target test point are measured and recorded by the test module, and then a whole-vehicle test model is established in the modal testing software.

[0082] The time-domain vibration data acquired by the test module includes acceleration, displacement, vehicle speed, and rotational speed signals measured at all target test points. All time-domain vibration data are connected to a unified data acquisition front-end. External parameter information includes the load weight of the driver and passenger seats of the vehicle under test, as well as the mass and position of the test module. It is important to note that a test operator is also present in the vehicle during testing to collect external parameter information. Prior to road testing, the weights of the driver and test operator need to be recorded, along with the mass of the test module and its position at each target test point.

[0083] After preparation, a road test will be conducted on a level road surface at a target speed of 80 km / h. It should be noted that the target speed can be set based on the speed the driver is concerned about or the speed at which they have complained about.

[0084] Step S204: Based on the time-domain vibration data, analyze whether the tire excitation source of the vehicle under test is the vehicle vibration excitation source.

[0085] Specifically, a Fourier transform is performed on the measured time-domain vibration data to obtain a vibration spectrum with a bandwidth of not less than 50 Hz and a frequency resolution of not less than 0.2 Hz. The frequency 'a' corresponding to the peak value is found in the vibration spectrum. Then, the tire rolling excitation frequency 'b' at the target vehicle speed is calculated using the vehicle speed signal at the target test point and the known tire rolling radius. If the amplitudes of 'a' and 'b' differ by less than 0.5 Hz, the tire excitation source of the vehicle under test can be determined as the vehicle vibration excitation source.

[0086] Optionally, in this embodiment, a vibration spectrum with a bandwidth of 0-20Hz and a frequency resolution of 0.2Hz is selected, such as... Figure 3As shown, the vibration peak occurs in the X direction, while the vibrations in the Y and Z directions are much smaller than those in the X direction. The peak frequency a in the X direction is 6.3Hz. For example, the tire model of this vehicle is 12R22.5. Based on the relationship with the vehicle speed of 80km / h, the tire rolling excitation frequency b at this speed can be calculated to be 6.4Hz. The difference between a and b is 0.1Hz, and the amplitude difference is within 0.5Hz. Therefore, it can be determined that the vehicle vibration is caused by tire excitation.

[0087] Step S206: If the tire excitation source of the vehicle under test is the vehicle vibration excitation source, then the first vibration mode information of the vehicle under test is obtained based on the time-domain vibration data.

[0088] Specifically, the vibration spectrum data is first analyzed. The frequency corresponding to the first peak point of the vibration spectrum from the road test is then identified; this is the first vibration frequency of the vehicle under test. Simultaneously, the vibration pattern corresponding to this frequency is observed; this is the first vibration pattern of the vehicle under test.

[0089] For example, the first vibration frequency of the vehicle under test is the peak frequency in the X direction, such as... Figure 3 The figure shows the vibration spectrum of the road test. The peak frequency a in the X direction is 6.3 Hz. The shaking vibration pattern near the peak frequency a in the X direction is observed.

[0090] Step S208: Based on the external parameter information of the vehicle under test, a bench test is conducted on the vehicle under test.

[0091] Specifically, after determining that the vehicle vibration problem was caused by excessive tire excitation, bench tests were conducted to simulate application scenarios with different tire excitation positions. By comparing the test parameters in the road test, the tire excitation position was further clarified.

[0092] For example, the vehicle under test has six wheels. During bench testing, the entire vehicle should be placed on a vibration table where each tire can be independently excited, such as... Figure 4 As shown in the diagram, there are three independently operable vibration tables on each side, totaling six on both sides of the vehicle. The vibration measurement points for the entire vehicle are consistent with those used in road testing. Each vibration table should be equipped with a laser displacement sensor to obtain the displacement signal of the vibration table during the test.

[0093] Step S210: Obtain the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test during the bench test.

[0094] Specifically, in the embodiments of this application, it should be noted that the combination types of tire excitation positions include at least all-wheel excitation, rear four-wheel excitation, front two-wheel excitation, left and right side phase-opposite excitation, rear four-wheel left and right phase-opposite excitation, rear four-wheel front and rear phase-opposite excitation, and rear four-wheel diagonal phase-in-phase excitation; the input low-frequency excitation signal includes a sine wave signal with an equal time-domain rate of change from 0 to 20Hz.

[0095] For example, to test the vibration response of a vehicle under test at various low-frequency frequencies, a continuous sinusoidal signal with a constant rate of change in the time domain needs to be output by the excitation table, or an excitation method with constant acceleration or constant velocity can be selected. The rate of change in the time domain of the signal frequency should not exceed 0.1 Hz / s. The rate of change in the time domain of the excitation signal should be the same at all frequencies, and the amplitude is recommended not to exceed 2 mm for commercial vehicles.

[0096] There are several combinations of tire excitation positions. It is recommended to first perform full-wheel excitation, then perform front and rear axle (front two wheels, rear two wheels) excitation separately, then perform left and right side anti-phase excitation, and finally perform excitation of other position combinations. For each excitation condition, it is necessary to acquire all acceleration and displacement signals obtained by the test module.

[0097] The vibration spectrum at each target test point is obtained by using the displacement signal of the vibration table, thus obtaining the second jitter vibration mode information. Specifically, the period of each sine wave is calculated using the displacement signal, and the signal frequency f1 at the corresponding time point t1 is obtained. Then, the vibration amplitude s1 at time point t2 is found using the vibration acceleration signal, thus obtaining the vibration amplitude s1 at frequency f1. The vibration amplitudes at other test points at other frequencies are obtained in the same way, ultimately yielding the vibration spectrum at each target test point, and thus the second jitter vibration mode information.

[0098] Step S212: Determine the location of the tire excitation source of the vehicle under test based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

[0099] Specifically, by comparing the vibration patterns at different excitation locations in bench tests with those in road tests, the specific tire excitation location can be determined. This method can accurately pinpoint the tire location causing vehicle vibration, enabling staff to quickly identify tire malfunctions and take appropriate measures.

[0100] In the aforementioned method for identifying low-frequency vibration excitation sources based on the testing process, the time-domain vibration data obtained through the testing module in road tests can determine that excessive tire excitation is the cause of vehicle vibration. Then, bench tests are conducted. During the bench tests, low-frequency excitation is applied to different tire excitation locations on the vehicle under test. By comparing the vibration patterns at different excitation locations in the bench tests with those in the road tests, the specific tire excitation location is determined. This method can accurately pinpoint the tire location causing vehicle vibration, enabling staff to quickly identify tire faults and take appropriate measures.

[0101] In one embodiment, analyzing whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source based on time-domain vibration data includes: obtaining the target test point frequency information and tire rolling excitation frequency information of the vehicle under test based on the time-domain vibration data; comparing the target test point frequency information and tire rolling excitation frequency information to obtain the frequency difference; if the frequency difference is within a preset frequency threshold range, then determining that the tire excitation source of the vehicle under test is a vehicle vibration excitation source.

[0102] In this embodiment, the frequency 'a' corresponding to the peak value is found from the vibration spectrum, and then the tire rolling excitation frequency 'b' at the target vehicle speed is calculated using the vehicle speed signal at the target test point and the known tire rolling radius. If the amplitude difference between 'a' and 'b' is within 0.5 Hz, the tire excitation source of the vehicle under test can be quickly determined to be the vehicle vibration excitation source.

[0103] In one embodiment, such as Figure 5 As shown, the second jitter vibration mode information of the low-frequency excitation signal input to the vehicle under test at different tire excitation positions during the bench test is obtained, including:

[0104] Step S502: Obtain acceleration and displacement information at each tire excitation location of the vehicle under test.

[0105] Step S504: Based on the acceleration and displacement information of each tire excitation position, obtain the second vibration spectrum at each tire excitation position in the bench test.

[0106] Step S506: Based on the second vibration spectrum at each tire excitation position in the bench test, analyze and obtain the second jitter vibration mode information of the low-frequency excitation signal input to the vehicle under test at each tire excitation position.

[0107] In this embodiment, the period of each sine wave is calculated using the displacement signal of the excitation table, and the signal frequency f1 at the corresponding time point t1 is obtained. Then, the vibration amplitude s1 at the time point t2 is found using the vibration acceleration signal. Thus, the vibration amplitude s1 at frequency f1 is obtained. The vibration amplitude at each measuring point at other frequencies is obtained in the same way. Finally, the vibration spectrum at each target test point is obtained, which enables rapid analysis of the second jitter vibration mode information of the low-frequency excitation signal input to each tire excitation position of the vehicle under test.

[0108] In one embodiment, determining the location of the tire excitation source of the vehicle under test based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations includes: obtaining a first vibration spectrum under the target working condition in a road test based on the first vibration pattern information; matching the first vibration spectrum with the second vibration spectrum at different tire excitation locations in a bench test to obtain a pre-selected tire excitation location that meets preset conditions; and determining the location of the tire excitation source of the vehicle under test based on the pre-selected tire excitation location, the first vibration pattern information, and the second vibration pattern information at different tire excitation locations.

[0109] Specifically, by comparing the vibration spectra of road tests and bench tests under different excitation conditions, the excitation conditions of bench tests with peak frequencies differing by no more than 0.5 Hz were selected as pre-selected conditions. Then, the vibration patterns of bench tests and road tests under the pre-selected conditions were compared; pre-selected conditions with identical vibration patterns became the target conditions. The tire excitation locations corresponding to the target conditions are the excitation sources of vehicle vibration. Subsequent design parameter adjustments and replacements of these tires can resolve related complaints. Furthermore, these tires can be subjected to more diverse signal excitations to study the overall vehicle vibration transmission characteristics.

[0110] It should be noted that the vibration spectrum changes more significantly in the 0.4-2Hz bandwidth; therefore, the vibration spectrum with a bandwidth of 0.4-2Hz is extracted, such as... Figure 6 As shown.

[0111] For example, such as Figure 7 As shown, by comparing the vibration spectra of road tests and bench tests under different excitation conditions, it was identified that the vibration spectrum at the target point of the middle and rear axles (i.e., the rear four wheels) of the original vehicle (i.e., the vehicle under test) under in-phase excitation has the same characteristics as the road test results. The maximum vibration direction is X-axis, and the peak frequency is 6.4Hz. The peak frequency in the road test is also 6.4Hz, with a difference of 0.1Hz, which is within the normal range. The vibration pattern is also the same as the road test results, with the chassis pitching around the front and the cab vibrating back and forth. Therefore, it can be determined that the abnormal vibration excitation location at 80km / h is the rear four wheels.

[0112] In one embodiment, the external parameter information of the vehicle under test includes the mass load information of the driver and passenger sides of the vehicle under test, as well as the mass and position information of the test module. Accordingly, based on the external parameter information of the vehicle under test, the bench test of the vehicle under test includes: configuring a vibration table with an individual excitation source for each tire of the vehicle under test; applying the same mass load to the driver and passenger sides, and keeping the mass and position of the test module arranged at the target test point the same; and inputting a continuous low-frequency excitation signal at different tire excitation positions of the vehicle under test through the vibration table to conduct the bench test.

[0113] Specifically, after the vehicle is placed on the vibration test bench, no cables or other equipment are used to secure or restrain it. For example, to prevent the vehicle from falling off the vibration test bench during the test, steel cables are used to connect a certain part of the vehicle to fixed stakes on the ground. The purpose is to ensure that the boundary conditions of the bench test and the road test are consistent, avoiding errors in the analysis results caused by different boundary conditions. The driver and passenger seats inside the vehicle need to be fitted with counterweights of the same mass based on the weight of the driver and test personnel measured during the road test. The test modules also need to be equipped with the same mass in the same locations.

[0114] For example, the number of vibration tables depends on the number of tires of the vehicle under test. Figure 4 There are three independently operable vibration tables on each side of the vehicle, totaling six on both sides. The target test points for the wheels under test are consistent with those used in road testing. Figure 7 As shown, laser displacement sensors were installed above each of the six vibration tables, mounted on sensor brackets. These sensors emitted lasers to measure the displacement of the vibration tables during the bench test. The driver and test operator weighed 80 kg and 65 kg respectively, with equal weights added to the driver's and passenger's seats. All other testing equipment was placed in the middle of the sleeper berth, consistent with the road test setup. Figure 6 As shown, the input signal of the excitation table contains a sinusoidal signal from 0 to 20Hz, with a time-domain change rate increasing by 0.1Hz / s each time, and a signal peak value of 1mm. A constant displacement excitation method is selected. Figure 8 As shown, the vibration measurement points for the entire vehicle are consistent with those used in the road test. Figure ① indicates the vibration table, Figure ② indicates the laser displacement sensor, Figure ③ indicates the bracket, and Figure ④ indicates the laser. A laser displacement sensor should be installed on each vibration table to obtain the displacement signal of the vibration table during the test.

[0115] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0116] Based on the same inventive concept, this application also provides a device for identifying low-frequency jitter excitation sources based on a test process, which is used to implement the aforementioned method for identifying low-frequency jitter excitation sources based on a test process. The solution provided by this device is similar to the solution described in the above method. Therefore, the specific limitations of one or more embodiments of the device for identifying low-frequency jitter excitation sources based on a test process provided below can be found in the limitations of the method for identifying low-frequency jitter excitation sources based on a test process described above, and will not be repeated here.

[0117] In one embodiment, such as Figure 9 As shown, a low-frequency jitter excitation source identification device based on the test process is provided, comprising:

[0118] Test module 902 is placed at the target test point of the vehicle under test during road testing to test the time-domain vibration data at the target test point under the target operating conditions.

[0119] The acquisition module 904 is used to acquire the time-domain vibration data of the target test point, as well as the external parameter information of the vehicle under test.

[0120] The judgment module 906 is used to determine whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source based on the time-domain vibration data.

[0121] The acquisition module 904 is also used to acquire the first vibration mode information of the vehicle under test based on the time-domain vibration data when the tire excitation source of the vehicle under test is the vehicle vibration excitation source.

[0122] The processing module 908 is used to perform bench tests on the vehicle under test based on the external parameter information of the vehicle under test and the test module 902 arranged at the target test point of the vehicle under test when the tire excitation source of the vehicle under test is used as the vehicle vibration excitation source.

[0123] The excitation table 910 is used to input low-frequency excitation signals at different tire excitation positions of the vehicle under test.

[0124] The acquisition module 904 is also used to acquire the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test.

[0125] The processing module 908 is also used to determine the location of the tire excitation source of the vehicle under test based on the first vibration morphology information and the second vibration morphology information at different tire excitation locations.

[0126] In one embodiment, the acquisition module 904 is further configured to acquire the target test point frequency information and tire rolling excitation frequency information of the vehicle under test, and obtain the frequency difference, based on the time-domain vibration data. The processing module 908 is further configured to compare the target test point frequency information and the tire rolling excitation frequency information; if the frequency difference is within a preset frequency threshold range, then the tire excitation source of the vehicle under test is determined to be the vehicle vibration excitation source.

[0127] In one embodiment, the acquisition module 904 is further configured to acquire acceleration and displacement information at each tire excitation position of the vehicle under test; and acquire the second vibration spectrum at each tire excitation position in the bench test based on the acceleration and displacement information at each tire excitation position. The processing module 908 is further configured to analyze and obtain the second jitter vibration mode information of the low-frequency excitation signal input to the vehicle under test at each tire excitation position based on the second vibration spectrum at each tire excitation position in the bench test.

[0128] In one embodiment, the acquisition module 904 is further configured to acquire a first vibration spectrum under the target working condition in the road test based on the first vibration morphology information. The processing module 908 is further configured to match the first vibration spectrum with the second vibration spectrum at different tire excitation positions in the bench test to obtain a pre-selected tire excitation position that meets preset conditions; and determine the position of the tire excitation source of the vehicle under test based on the pre-selected tire excitation position, the first vibration morphology information, and the second vibration morphology information at different tire excitation positions.

[0129] In one embodiment, the processing module 908 is further configured to provide each tire of the vehicle under test with a separate excitation source on a vibration table; to apply the same mass load to the driver and passenger sides, and to keep the test modules arranged at the target test points of the same mass and unchanged position; and to input continuous low-frequency excitation signals at different tire excitation positions of the vehicle under test through the vibration table 910 for bench testing.

[0130] Each module in the aforementioned low-frequency jitter excitation source identification device based on the experimental process can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the corresponding operations of each module.

[0131] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 10 As shown, the computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores relevant data for identifying low-frequency jitter excitation sources based on a test process. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements a method for identifying low-frequency jitter excitation sources based on a test process.

[0132] Those skilled in the art will understand that Figure 9 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0133] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0134] Step S202: Under target operating conditions, conduct road tests on the vehicle under test. By using test modules placed at the target test points of the vehicle under test, acquire time-domain vibration data of the target test points and external parameter information of the vehicle under test.

[0135] Step S204: Based on the time-domain vibration data, analyze whether the tire excitation source of the vehicle under test is the vehicle vibration excitation source.

[0136] Step S206: If the tire excitation source of the vehicle under test is the vehicle vibration excitation source, then the first vibration mode information of the vehicle under test is obtained based on the time-domain vibration data.

[0137] Step S208: Based on the external parameter information of the vehicle under test, a bench test is conducted on the vehicle under test.

[0138] Step S210: Obtain the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test during the bench test;

[0139] Step S212: Determine the location of the tire excitation source of the vehicle under test based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

[0140] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0141] Step S202: Under target operating conditions, conduct road tests on the vehicle under test. By using test modules placed at the target test points of the vehicle under test, acquire time-domain vibration data of the target test points and external parameter information of the vehicle under test.

[0142] Step S204: Based on the time-domain vibration data, analyze whether the tire excitation source of the vehicle under test is the vehicle vibration excitation source.

[0143] Step S206: If the tire excitation source of the vehicle under test is the vehicle vibration excitation source, then the first vibration mode information of the vehicle under test is obtained based on the time-domain vibration data.

[0144] Step S208: Based on the external parameter information of the vehicle under test, a bench test is conducted on the vehicle under test.

[0145] Step S210: Obtain the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test during the bench test;

[0146] Step S212: Determine the location of the tire excitation source of the vehicle under test based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

[0147] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps:

[0148] Step S202: Under target operating conditions, conduct road tests on the vehicle under test. By using test modules placed at the target test points of the vehicle under test, acquire time-domain vibration data of the target test points and external parameter information of the vehicle under test.

[0149] Step S204: Based on the time-domain vibration data, analyze whether the tire excitation source of the vehicle under test is the vehicle vibration excitation source.

[0150] Step S206: If the tire excitation source of the vehicle under test is the vehicle vibration excitation source, then the first vibration mode information of the vehicle under test is obtained based on the time-domain vibration data.

[0151] Step S208: Based on the external parameter information of the vehicle under test, a bench test is conducted on the vehicle under test.

[0152] Step S210: Obtain the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test during the bench test;

[0153] Step S212: Determine the location of the tire excitation source of the vehicle under test based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

[0154] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data shall comply with the relevant laws, regulations and standards of the relevant countries and regions.

[0155] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0156] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0157] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for identifying low-frequency jitter excitation sources based on experimental processes, characterized in that, The method includes: Under target operating conditions, a road test is conducted on the vehicle under test. The test module is arranged at the target test point of the vehicle under test to obtain the time-domain vibration data of the target test point and the external parameter information of the vehicle under test. Based on the time-domain vibration data, analyze whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source; If the tire excitation source of the vehicle under test is the vehicle vibration excitation source, then the first vibration mode information of the vehicle under test is obtained based on the time-domain vibration data. Based on the external parameter information of the vehicle under test, a bench test is conducted on the vehicle under test; Acquire the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test during the bench test; The location of the tire excitation source of the vehicle under test is determined based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

2. The method according to claim 1, characterized in that, The step of analyzing whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source based on the time-domain vibration data includes: Based on the time-domain vibration data, obtain the target test point frequency information and tire rolling excitation frequency information of the vehicle under test; The frequency difference is obtained by comparing the frequency information of the target test point with the tire rolling excitation frequency information. If the frequency difference is within a preset frequency threshold range, then the tire excitation source of the vehicle under test is determined to be the vehicle vibration excitation source.

3. The method according to claim 1, characterized in that, The different tire excitation positions include: full-wheel excitation, rear four-wheel excitation, front two-wheel excitation, left and right side reverse phase excitation, rear four-wheel left and right reverse phase excitation, rear four-wheel front and rear reverse phase excitation, and rear four-wheel diagonal same phase excitation; The input low-frequency excitation signal includes a sinusoidal signal with an equal time-domain rate of change from 0 to 20 Hz.

4. The method according to claim 3, characterized in that, The acquisition of the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test during the bench test includes: Acquire acceleration and displacement information at each tire excitation location of the vehicle under test; Based on the acceleration and displacement information of each tire excitation position, the second vibration spectrum at each tire excitation position in the bench test is obtained. Based on the second vibration spectrum at each tire excitation position during the bench test, the second jitter vibration mode information of the low-frequency excitation signal input to the vehicle under test at each tire excitation position is obtained by analysis.

5. The method according to claim 1, characterized in that, The step of determining the location of the tire excitation source of the vehicle under test based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations includes: Based on the first shaking vibration pattern information, the first vibration spectrum under the target working condition in the road test is obtained; The first vibration spectrum is matched with the second vibration spectrum at different tire excitation positions in the bench test to obtain the pre-selected tire excitation positions that meet the preset conditions. The location of the tire excitation source of the vehicle under test is determined based on the pre-selected tire excitation location, the first vibration pattern information, and the second vibration pattern information of different tire excitation locations.

6. The method according to claim 1, characterized in that, The external parameter information of the vehicle under test includes the mass load information of the driver and passenger seats, as well as the mass and position information of the test module; correspondingly, The step of conducting bench tests on the vehicle under test based on the external parameter information of the vehicle under test includes: Each tire of the vehicle under test is equipped with a vibration table with an individual excitation source. The same mass load is applied to the driver and passenger seats, and the test modules placed at the target test points are kept to have the same mass and remain in the same position. A bench test is conducted by inputting a continuous low-frequency excitation signal at different tire excitation positions of the vehicle under test using a vibration table.

7. A low-frequency jitter excitation source identification device based on an experimental process, characterized in that, The device includes: The test module is set up at the target test point of the vehicle under test during road testing to test the time-domain vibration data at the target test point under the target operating conditions. The acquisition module is used to acquire time-domain vibration data of the target test point, as well as external parameter information of the vehicle under test; The judgment module is used to determine whether the tire excitation source of the vehicle under test is a vehicle vibration excitation source based on the time-domain vibration data. The acquisition module is also used to acquire the first vibration mode information of the vehicle under test based on the time-domain vibration data when the tire excitation source of the vehicle under test is the vehicle vibration excitation source. The processing module is used to perform bench tests on the vehicle under test when the tire excitation source of the vehicle under test is used as the vehicle vibration excitation source, based on the external parameter information of the vehicle under test and the test module arranged at the target test point of the vehicle under test. A vibration table is used to input low-frequency excitation signals at different tire excitation positions of the vehicle under test. The acquisition module is also used to acquire the second jitter vibration mode information of the low-frequency excitation signal input at different tire excitation positions of the vehicle under test; The processing module is also used to determine the location of the tire excitation source of the vehicle under test based on the first vibration pattern information and the second vibration pattern information at different tire excitation locations.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

Images