Gearbox test method and test bench for simulating vehicle driving environment

Abstract

The invention relates to the technical field of gearbox testing, in particular to a gearbox testing method and a testing stand for simulating a vehicle driving environment, and the method comprises the steps: collecting vibration signals of a to-be-tested gearbox in different testing environments and different time periods; calculating an environment vibration interference coefficient and an environment interference coefficient of the time period; obtaining a fault vibration coefficient of the time period; and according to the fault vibration coefficient and the environment interference coefficient of the time period, calculating the fault possibility of the time period, and according to the fault possibility, completing a gearbox test for simulating a vehicle driving environment. According to the invention, the accuracy of gearbox test results can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gearbox testing, in particular to a gearbox test method and test bench for simulating vehicle driving environments. BACKGROUND

[0002] A gearbox is a main kinetic energy transmission device of a vehicle, which can coordinate the rotation speed of an engine and the actual driving speed of a wheel to ensure that the engine is in an optimal power performance state, and the stability of the operation of the gearbox will directly affect the normal operation of the entire vehicle. Monitoring the working state of the gearbox can timely find abnormalities and ensure safe driving of the vehicle. Generally, different vehicle driving environments are simulated, vibration signals collected in each driving environment are analyzed and identified, and the operation of the gearbox in each driving environment is evaluated to realize fault detection and positioning of the gearbox.

[0003] However, in different driving environments, the vibration signals specific to some driving environments are similar to abnormal vibration signals, for example, the vibration signals of a vehicle driving through a continuous deceleration zone present a regular impact-type peak, which is similar to the abnormal vibration signals of a fault gearbox. Therefore, various different driving environments easily interfere with the vibration signals, making it difficult to identify the real fault condition of the gearbox and easily causing the accuracy of the gearbox test results to decrease. SUMMARY

[0004] To solve the above technical problems, the present application provides a gearbox test method and test bench for simulating vehicle driving environments, and the technical solutions adopted are as follows: In a first aspect, one embodiment of the present application provides a gearbox test method for simulating vehicle driving environments, which includes the following steps: Collecting vibration signals of a gearbox to be tested in different test environments and at different time periods; According to the differences of all peaks in the vibration signals, high peaks in the vibration signals are screened, the environmental vibration interference coefficients of each time period are calculated according to the differences of all high peaks in the vibration signals of the same time period in all different time periods and the differences of the collection time intervals, and the environmental interference coefficients of each time period are calculated in combination with the difference of the change trend of the vibration signals of the time period; According to the differences of the high peaks in the two sub-periods divided by the time period, the differences of the time intervals between all high peaks in the vibration signals, and the differences of the number of peaks contained in the time period and other different time periods, the fault vibration coefficients of the time period are obtained; According to the fault vibration coefficients and the environmental interference coefficients of the time period, the fault possibility of the time period is calculated, and the gearbox test for simulating vehicle driving environments is completed according to the fault possibility.

[0005] Further, the screening method of high peaks in the vibration signal is: The average of the peak values of all peaks in the vibration signal of the same period is recorded as the average peak value, and the peak values greater than the average peak value in the vibration signal of the same period are all recorded as high peaks.

[0006] Further, the specific acquisition method of the environmental vibration interference coefficient of the period is: The normalized value of the average of the time intervals between all high peaks in the vibration signal is recorded as the high peak average interval of the same period; any period is recorded as a target period, and the first difference between the target period and other periods is calculated according to the difference in the high peak average interval between the target period and other periods. The variance of all peak values in the vibration signal of the same period is recorded as the peak value variance of the same period; the second difference between the target period and other periods is calculated according to the difference in the peak value variance between the target period and other periods. The positive correlation processing result of the first difference and the second difference between the target period and all other periods is recorded as the environmental vibration interference coefficient of the target period.

[0007] Further, the acquisition method of the first difference and the second difference is: The absolute value of the difference in the high peak average interval between the target period and other periods is recorded as the first difference between the target period and other periods. The absolute value of the difference in the peak value variance between the target period and other periods is recorded as the second difference between the target period and other periods.

[0008] Further, the specific method for calculating the environmental interference coefficient of each period by combining the change trend difference of the vibration signal of the period is: The curve fitting result of the vibration signal of the period is recorded as the vibration signal curve of the period, the cumulative sum of the cosine similarity between the vibration signal curves of the target period and all other periods is recorded as the curve similarity of the target period, and the ratio of the environmental vibration interference coefficient of the target period to the curve similarity is recorded as the environmental interference coefficient of the target period.

[0009] Further, the specific steps for obtaining the fault vibration coefficient of the period are: The segmented difference of the period is calculated according to the difference in the high peaks in the two sub-periods of the period. The peak difference of the period is calculated according to the difference in the time intervals between all high peaks in the vibration signal. The normalized value of the variance of the time intervals between all high peaks in the vibration signal is recorded as the interval variance of the period corresponding to the vibration signal. The negative correlation processing result of the segment difference, the peak difference and the interval variance of the time period is recorded as a fault vibration coefficient of the time period.

[0010] Further, the acquisition method of the segment difference of the time period is: The absolute value of the difference of the normalized values of the mean values of the high wave peaks in the two sub-periods of the same time period is recorded as a segment difference of the time period.

[0011] Further, the acquisition method of the peak difference of the time period is: The number of the peaks contained in the time period is recorded as a peak number of the time period, and the absolute value of the cumulative sum of the difference of the peak numbers of the time period and all other time periods is recorded as a peak difference of the time period.

[0012] Further, the fault possibility of the time period is calculated according to the fault vibration coefficient and the environmental interference coefficient of the time period, and the gearbox test simulating the vehicle driving environment is completed according to the fault possibility, and the specific steps include: The normalized value of the ratio of the fault vibration coefficient and the environmental interference coefficient of the time period is recorded as a fault possibility of the time period. All vibration signals of the time period with the fault possibility greater than a preset fault segmentation threshold are subjected to abnormality detection, when the vibration signals have an abnormality, it is determined that the gearbox is abnormal, the test is stopped and the gearbox is repaired; otherwise, the test of the gearbox is continued until all tests are completed.

[0013] In a second aspect, another embodiment of the present application provides a gearbox test bench simulating a vehicle driving environment, including a memory, a processor and a computer program stored in the memory and executable on the processor, and when the processor executes the computer program, the steps of the gearbox test method simulating the vehicle driving environment are implemented.

[0014] The embodiments of the present application have at least the following beneficial effects: The application notes that under part of the driving environment, the vibration signal of the normal gearbox may present similar overall characteristics with the vibration signal of the fault gearbox. In order to exclude the influence of the special similar vibration of the vehicle driving in the complex vehicle condition on the gearbox experiment, according to the characteristics that the frequency and vibration intensity of the external vibration interference on the gearbox are relatively high in the complex environment, the significance of the characteristics that the fluctuation amplitude of the amplitude in the vibration signal is increased and the distribution regularity of the vibration peak is relatively less obvious is evaluated, and the environment interference coefficient of the period is obtained. When the environment interference coefficient of the target period is larger, the possibility that the vehicle is abnormally affected by the driving environment in the target period is larger. Further, according to the characteristics that the amplitude of the vibration frequency generated in the fault condition is obviously increased, and many frequency peaks different from the normal frequency peak appear, the characteristics that the change of the vibration signal collected in the period is caused by the vehicle driving environment change rather than the fault are evaluated, and the fault vibration coefficient of the period is obtained. When the fault vibration coefficient of the period is larger, the newly increased amplitude of the vibration frequency is less obvious, and the characteristics that the peak of the vibration signal is offset and weakened with the passage of time are more obvious. At this time, the possibility that the change of the vibration signal collected in the period is caused by the vehicle driving environment change is larger. Finally, according to the fault vibration coefficient and the environment interference coefficient of the period, the fault possibility of the period is calculated, and the gearbox test in the simulated vehicle driving environment is completed according to the fault possibility, so as to solve the problem that different driving environments easily interfere with the vibration signal and cause the accuracy of the gearbox test result to decrease, and improve the stability and reliability of the gearbox test in the simulated vehicle driving environment. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, and the advantages thereof, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0016] Figure 1 The step flow chart of the gearbox test method in the simulated vehicle driving environment provided by an embodiment of the present application is shown in the figure. Figure 2 The high peak acquisition flow chart provided by an embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0017] In order to further illustrate the technical means and effects taken by the present application to achieve the predetermined object, the specific embodiments, structure, features and effects of the gearbox test method and test bench for simulating vehicle driving environment according to the present application are described in detail as follows in combination with the drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0019] The specific scheme of the gearbox test method and test bench for simulating vehicle driving environment provided by the present application is described in detail below in combination with the drawings.

[0020] Please refer to Figure 1 which shows the step flowchart of the gearbox test method for simulating vehicle driving environment provided by one embodiment of the present application, which comprises the following steps: Step S001, collecting the vibration signals of the gearbox to be tested in different test environments and different time periods.

[0021] The gearbox to be tested is installed on the test bench, ensuring firm installation, aligning the connecting shaft to avoid loosening or deviation during the test, connecting the input shaft and output shaft of the gearbox, and selecting appropriate connection methods such as shaft coupling, transmission shaft, etc. according to the test requirements. After the installation of the gearbox to be tested is completed, the test parameters are set on the control console, including input speed, output torque, loading method, test time, etc. Start the test bench and collect the vibration signals of the gearbox to be tested in different test environments and different time periods during the test through the test bench.

[0022] It should be understood that in order to reduce the differences between the vibration signals collected in different time periods, the vibration signals are normalized to make the amplitude of the vibration signals greater than or equal to -1 and less than or equal to 1.

[0023] In this embodiment, 6 minutes is taken as a time period; in each time period, the sampling frequency of the vibration signal is 12 kHz; the Z-Score standard normalization method is used to normalize the vibration signals in this embodiment, and other methods such as the existing maximum and minimum normalization method can be used for normalization in actual application, which is not limited here.

[0024] At this point, the vibration signals of the gearbox to be tested in different test environments and different time periods are obtained.

[0025] Step S002, according to the difference of all wave peaks in the vibration signal, screening high wave peaks in the vibration signal, according to the difference of all high wave peaks in the vibration signal of the same period in all different time periods and the difference of the collection time interval, respectively calculating the environmental vibration interference coefficient of each period, combining the change trend difference of the vibration signal of the period, respectively calculating the environmental interference coefficient of each period.

[0026] Generally, in the process of normal driving of the vehicle, the vibration signal of the gearbox is relatively stable in the time domain, the signal amplitude fluctuation is small, and there is a certain periodicity; when the gearbox has abnormal conditions such as gear transmission system failure, the vibration signal of the gearbox will have a large amplitude fluctuation. When the test bench simulates different vehicle driving environments, it simulates the driving of the vehicle under different working conditions and different road conditions. When the vehicle drives on uneven road, the amplitude of the vibration signal will also increase obviously, and the amplitude fluctuation difference is obvious. That is, under part of the driving environment, the vibration signal of the normal gearbox may have similar overall characteristics with the vibration signal of the fault gearbox. Therefore, the influence of the special similar vibration of the vehicle driving in complex vehicle conditions on the gearbox experiment needs to be excluded.

[0027] Specifically, when the vehicle drives at a constant speed on a normal flat road, the periodicity of the vibration signal of the gearbox is more obvious, and the overall amplitude fluctuation change is small. When the gearbox has abnormal conditions, the vibration signal will have a certain abnormal amplitude, and the vibration signal change caused by different fault conditions is different. For example, gear tooth failure will cause the appearance of impact type vibration peak, but the periodicity change amplitude of the overall vibration signal is small. When the vehicle driving environment is uneven road or complex environment, the external vibration interference frequency and vibration intensity of the gearbox are randomly high, which is specifically manifested as the increase of the fluctuation amplitude of the vibration signal and the relatively unclear distribution regularity of the vibration peak value.

[0028] The average of the peak values of all wave peaks in the vibration signal of the same period is recorded as the average peak value. All peak values greater than the average peak value in the vibration signal of the same period are recorded as high wave peaks. The normalized value of the average of the time intervals between all high wave peaks in the vibration signal is recorded as the high wave peak average interval of the same period. The variance of all peak values in the vibration signal of the same period is recorded as the peak value variance of the same period.

[0029] The high wave peak acquisition flow chart is shown in Figure 2 It should be noted that the Z-Score standard normalization method is used to calculate the normalized value in this embodiment. In actual application, other methods such as the maximum and minimum value normalization method, sigmoid function and other methods of prior art can be used to calculate the normalized value, which is not limited here.

[0030] The absolute value of the difference between the target period and the high peak average interval of other periods is recorded as the first difference between the target period and other periods; the absolute value of the difference between the target period and the peak value variance of other periods is recorded as the second difference between the target period and other periods; and the positive correlation processing result of the first difference and the second difference between the target period and all other periods is recorded as the environmental vibration interference coefficient of the target period.

[0031] It can be understood that the positive correlation processing of the first difference and the second difference between the target period and all other periods ensures that the first difference and the second difference between the target period and all other periods are respectively positively correlated with the environmental vibration interference coefficient of the target period. It can be understood that the positive correlation in the present application refers to the relationship between the independent variable and the dependent variable, the independent variable is the first difference and the second difference between the target period and all other periods, and the dependent variable is the environmental vibration interference coefficient of the target period. The positive correlation is that the dependent variable increases (decreases) as the independent variable increases (decreases), which can be an additive relationship, a multiplicative relationship, etc.

[0032] Preferably, as an embodiment of the present application, the cumulative sum of the product of the first difference and the second difference between the target period and all other periods is recorded as the environmental vibration interference coefficient of the target period.

[0033] The environmental vibration interference coefficient of the target period is used to evaluate the significance of the characteristics of the vibration signal of the target period that are affected by the driving environment. When the environmental vibration interference coefficient of the target period is larger, the discrete degree of the peak value of the wave peak of the vibration signal of the target period increases, the time interval between all high wave peaks in the vibration signal changes significantly, and the possibility of the vehicle being abnormal in the target period due to the influence of the driving environment is greater.

[0034] Further, the vibration influence generated by the vehicle driving in different environments will cause the overall vibration signal form difference between periods to be more obvious, specifically, the vibration signal curve form difference between periods is larger. The vibration signal curve of each period is obtained by using the minimum binomial fitting algorithm to fit the vibration signal of each period. The cumulative sum of the cosine similarity between the vibration signal curve of the target period and the vibration signal curve of all other periods is recorded as the curve similarity of the target period. The ratio of the environmental vibration interference coefficient of the target period to the curve similarity is recorded as the environmental interference coefficient of the target period.

[0035] When the environmental interference coefficient of the target period is larger, the curve form difference between the vibration signal curve collected in the target period and the vibration signal curve collected in other periods is larger, and the possibility of the vehicle being abnormal in the target period due to the influence of the driving environment is greater.

[0036] The environmental interference coefficient of each time period can be obtained in the same way.

[0037] Thus, the environmental interference coefficients of all time periods are obtained.

[0038] In step S003, the fault vibration coefficient of the time period is obtained according to the difference between the high peaks in the two sub-periods, the difference between the time intervals of all high peaks in the vibration signal, and the difference between the number of peaks contained in the time period and other different time periods.

[0039] The environment in which the vehicle travels is complex, and when simulating special urban road conditions such as schools, hospitals, and continuous downhill roads, there are continuous and large numbers of speed bumps on these road sections, and multiple groups of speed bumps appear at intervals, so that the vibration signals collected in the corresponding time period exhibit a certain regularity. When the gearbox of the vehicle has a gear fault or other faults, the collected vibration signal may also have a similar regularity of impact-type vibration. However, the two similar vibration signals have differences.

[0040] Specifically, compared with the vibration signal of the normally running vehicle gearbox, the amplitude of the vibration frequency generated in the fault condition will be significantly increased, and there will be many frequency peaks different from the normal frequency peaks, which are expressed as regular impact-type peaks in the time domain. When the vehicle travels through continuous speed bumps, the speed of the vehicle will slow down relatively, and there is a certain difference in the speed of the vehicle when entering and leaving the speed bump area, which causes the peaks of the vibration signal to shift and weaken over time.

[0041] The time period is divided into two sub-periods, which are referred to as the first segment and the second segment. The absolute value of the difference between the normalized values of the mean of the high peaks in the first segment and the second segment of the same time period is referred to as the segment difference of the time period. The number of peaks contained in the time period is referred to as the peak number of the time period, and the absolute value of the cumulative sum of the difference between the peak number of the time period and the peak number of all other time periods is referred to as the peak difference of the time period. The normalized value of the variance of the time interval between all high peaks in the vibration signal is referred to as the interval variance of the time period corresponding to the vibration signal. The negative correlation processing result of the segment difference, the peak difference, and the interval variance is referred to as the fault vibration coefficient of the time period.

[0042] It can be understood that the segment difference, the peak difference, and the interval variance of the time period are negatively correlated, that is, the segment difference, the peak difference, and the interval variance of the time period are negatively correlated with the fault vibration coefficient of the time period. It can be understood that the negative correlation in the present application refers to the relationship between the independent variable and the dependent variable, the independent variable is the segment difference, the peak difference, and the interval variance of the time period, and the dependent variable is the fault vibration coefficient of the time period. The negative correlation is that the dependent variable decreases (increases) as the independent variable increases (decreases), which can be an inverse relationship, a subtraction relationship, etc.

[0043] Preferably, as an embodiment of the present application, the reciprocal of the product of the segment difference, the peak difference and the interval variance of the time period is recorded as the fault vibration coefficient of the time period.

[0044] In the process of calculating the reciprocal, in order to avoid the case that the denominator is zero, a preset value is added to the denominator, and an embodiment of the preset value is 0.001.

[0045] The fault vibration coefficient of the time period is used to evaluate the possibility that the change of the vibration signal collected in the time period is caused by the change of the vehicle driving environment rather than the fault. When the fault vibration coefficient of the time period is larger, the newly appearing elevated amplitude in the vibration frequency is less obvious, and the features of the shift and weakening of the peak value of the vibration signal over time are more obvious, and at this time, the possibility that the change of the vibration signal collected in the time period is caused by the change of the vehicle driving environment is greater.

[0046] At this point, the fault vibration coefficient of each time period is obtained.

[0047] Step S004, according to the fault vibration coefficient of the time period and the environmental interference coefficient, the fault possibility of the time period is calculated, and the gearbox test simulating the vehicle driving environment is completed according to the fault possibility.

[0048] The normalized value of the ratio of the fault vibration coefficient of the time period and the environmental interference coefficient is recorded as the fault possibility of the time period.

[0049] The fault possibility of the time period is used to evaluate the possibility that the vibration signal collected in the time period contains the vibration signal caused by the fault of the transmission, and the greater the fault possibility of the time period, the greater the possibility that the gearbox of the automobile is affected by the fault in the time period.

[0050] The labeled historical test data in the database is extracted from the console by the test personnel in the field, the fault possibility of each time period corresponding to all historical test data is calculated, the cross-validation method is used to process the fault possibility of each time period corresponding to all historical test data, and the fault segmentation threshold is obtained.

[0051] The time period with a fault possibility greater than the fault segmentation threshold is marked as a marked time period of the gearbox, and all vibration signals of the marked time period are subjected to abnormality detection using an abnormality detection algorithm. When the vibration signal is abnormal, it is determined that the gearbox is abnormal, the test of the test bench on the gearbox is stopped, and the gearbox is repaired; when the marked time period or the vibration signal is not identified, the test of the gearbox is continued until all tests are completed.

[0052] At this point, the gearbox test simulating the vehicle driving environment is realized.

[0053] The embodiment of the present application further provides a gearbox test bench for simulating a vehicle driving environment, comprising a memory, a processor and a computer program stored in the memory and capable of running on the processor, and the processor implements the steps described above when executing the computer program. Since the gearbox test method for simulating a vehicle driving environment has been described in detail above, no further description is given.

[0054] It should be noted that the above-mentioned sequence of the embodiments of the present application is only for description, and does not represent the advantages and disadvantages of the embodiments. Moreover, the above-mentioned embodiments of the present application are described. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multi-task processing and parallel processing are also possible or can be advantageous.

[0055] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; modifying the technical solutions described in the above embodiments, or equivalently replacing some of the technical features, does not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A transmission test method simulating a vehicle driving environment, characterized in that, The method includes the following steps: Vibration signals of the gearbox under test were collected in different test environments and at different times. Based on the differences among all peaks in the vibration signal, high peaks in the vibration signal are filtered out. Based on the differences among all high peaks in the vibration signal of the same time period in all different time periods and the differences in the acquisition time interval, the environmental vibration interference coefficient of each time period is calculated. Combined with the differences in the changing trend of the vibration signal in time periods, the environmental interference coefficient of each time period is calculated. The fault vibration coefficient of a time period is obtained by dividing the time period into two sub-time periods, the difference in the time interval between all high peaks in the vibration signal, and the difference in the number of peaks contained in the time period compared with other different time periods. Based on the fault vibration coefficient and environmental interference coefficient of the time period, the probability of fault during the time period is calculated, and a transmission test simulating the vehicle driving environment is completed based on the probability of fault.

2. The transmission test method simulating a vehicle driving environment according to claim 1, characterized in that, The method for filtering high peaks in the vibration signal is as follows: The average peak value of all peak values ​​in the vibration signal during the same time period is recorded as the average peak value. Peak values ​​in the vibration signal during the same time period that are greater than the average peak value are recorded as high peak values.

3. The transmission test method simulating a vehicle driving environment according to claim 1, characterized in that, The specific method for obtaining the environmental vibration interference coefficient during the specified time period is as follows: The normalized value of the mean time interval between all high peaks in the vibration signal is denoted as the average interval between high peaks in the same time period; any time period is denoted as the target time period, and the first difference between the target time period and other time periods is calculated based on the difference between the average interval between high peaks in the target time period and other time periods. The variance of all peak values ​​in the vibration signal during the same time period is denoted as the peak variance during the same time period. Calculate the second difference between the target time period and other time periods based on the difference in peak variance between the target time period and other time periods; The positive correlation between the first and second differences between the target time period and all other time periods is recorded as the environmental vibration disturbance coefficient for the target time period.

4. The transmission test method simulating a vehicle driving environment according to claim 3, characterized in that, The methods for obtaining the first difference and the second difference are as follows: The absolute value of the difference between the average interval of the peaks of the target time period and other time periods is denoted as the first difference between the target time period and other time periods. The absolute value of the difference between the peak variance of the target time period and other time periods is denoted as the second difference between the target time period and other time periods.

5. The transmission test method simulating a vehicle driving environment according to claim 1, characterized in that, The method for calculating the environmental interference coefficient for each time period by considering the differences in the variation trend of the vibration signal over the combined time period is as follows: The curve fitting result of the vibration signal of the time period is denoted as the vibration signal curve of the time period. The sum of the cosine similarity between the vibration signal curves of the target time period and all other time periods is denoted as the curve similarity of the target time period. The ratio of the environmental vibration interference coefficient of the target time period to the curve similarity is denoted as the environmental interference coefficient of the target time period.

6. The transmission test method simulating a vehicle driving environment according to claim 1, characterized in that, The specific steps for obtaining the fault vibration coefficient during the specified time period are as follows: The segmentation difference of the time period is calculated based on the difference in the high peak within the two sub-time periods when the time period is evenly divided. The peak value difference for each time period is calculated based on the difference in the time interval between all high peaks in the vibration signal. The normalized value of the variance of the time interval between all high peaks in the vibration signal is denoted as the interval variance of the corresponding time period of the vibration signal. The negative correlation results of segment differences, peak differences, and interval variances in time periods are denoted as the fault vibration coefficient of the time period.

7. The transmission test method simulating a vehicle driving environment according to claim 6, characterized in that, The method for obtaining the segment differences of the time period is as follows: Divide a time period into two sub-time periods. The absolute value of the difference between the normalized values ​​of the mean of the peak values ​​in the two sub-time periods of the same time period is denoted as the segment difference of the time period.

8. The transmission test method simulating a vehicle driving environment according to claim 6, characterized in that, The method for obtaining the peak difference during the time period is as follows: The number of peaks contained within a time period is denoted as the peak number of the time period. The sum of the absolute values ​​of the differences between the peak numbers of the time period and those of all other time periods is denoted as the peak difference of the time period.

9. The transmission test method simulating a vehicle driving environment according to claim 1, characterized in that, The specific steps involved in calculating the probability of a fault during a given time period based on the fault vibration coefficient and environmental interference coefficient, and then conducting a transmission test simulating a vehicle driving environment based on that probability, are as follows: The normalized value of the ratio of the fault vibration coefficient to the environmental disturbance coefficient during a time period is denoted as the fault probability during that time period. For all vibration signals in time periods where the probability of failure is greater than the preset fault segmentation threshold, anomaly detection is performed. If an anomaly is found in the vibration signal, the transmission is determined to be faulty, the test is stopped, and the transmission is repaired; otherwise, the transmission test continues until all tests are completed.

10. A transmission test bench simulating a vehicle driving environment, 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 computer program, it implements the steps of the transmission test method for simulating a vehicle driving environment as described in any one of claims 1 to 9.

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