A data processing method based on a road spectrum bench testing machine

Abstract

This invention proposes a data processing method based on a road spectrum bench tester for processing drive shaft operating signal data and drive shaft signal data related to the acquisition frequency during road tests. The processing method analyzes unreasonable data and retains the drive shaft operating signal in the road spectrum data by ignoring reasonable data. Specifically, it first identifies data exceeding the equipment's allowable range, then averages this data with data from the next time step. If the average is within the equipment's allowable range, it continues to calculate and output the average of the data exceeding the allowable range and the next time step data. If it is outside the allowable range, it continues to calculate the average until it falls within the allowable range, and then outputs the average. This invention analyzes only unreasonable data, preserving the drive shaft operating signal in the road spectrum to the greatest extent possible.

Description

Technical Field

[0001] This invention relates to the field of durability testing machine bench test data processing technology, and in particular to a data processing method based on a road spectrum bench test machine. Background Technology

[0002] During normal vehicle operation, the drive shaft system experiences certain torque and speed, transmitting these parameters to the wheels to propel the vehicle. Sensor devices collect parameters of the drive shaft during road tests at a test track (such as yaw angle, speed, torque, and vertical vibration). The collected data is then properly processed and imported into high-dynamic durability testing equipment. This is currently the method for conducting durability tests on drive shafts on a test bench, simulating real road conditions.

[0003] Currently, the mainstream method for processing raw signals is to use filtering to handle numerical abrupt changes caused by information interference. A filter is a frequency-selective circuit that allows useful signal frequencies to pass through while filtering out interfering signal frequencies. Filters can be classified into low-pass, high-pass, band-pass, and band-stop filters based on the frequency range they allow signals to pass through. In the filtered data, since the operating signals of the drive shaft (swing angle, speed, torque, vertical vibration, etc.) are mainly concentrated in the low-frequency range, a 30Hz low-pass filter is currently the mainstream choice for filtering. This can reduce the impact of the high-frequency range in the acquired signal on the durability and lifespan of the drive shaft system. After filtering, the road spectrum signal becomes smoother.

[0004] However, for harsh working conditions such as small washboard roads and off-road roads, the uncertainty of the force on the drive shaft increases, and the working signals (swing angle, speed, torque, vertical vibration, etc.) themselves have the characteristic of rapid data change. If filtering methods are used at this time, it will cause large-scale data distortion and make it impossible to accurately simulate the real road conditions of the drive shaft on the test bench.

[0005] Therefore, current mainstream filtering methods can, to some extent, solve the problem of numerical abrupt changes caused by information interference. However, the following problems still exist:

[0006] 1. Under harsh working conditions, the data after filtering will cause large-scale distortion and cannot truly reflect the various working information of the drive shaft (sway angle, speed, torque, vertical vibration, etc.) during the road test.

[0007] 2. There is controversy regarding the choice of a 30Hz low-pass filter frequency during processing. For data processing on complex road surfaces, using a lower filter frequency can ensure that the processed data meets the equipment's limits but may result in distortion; using a higher filter frequency can alleviate data distortion to some extent, but the processed data may still fall short of the equipment's capabilities.

[0008] 3. Based on point 2 above, the best frequency for filtering is when the processed data just reaches the limit of the equipment's capabilities. This requires a lot of attempts by data processing engineers, which is not only time-consuming but also not universal. New spectrum cannot be filtered using the previous frequency, and a new frequency needs to be found. Summary of the Invention

[0009] This invention proposes a data processing method based on a road spectrum bench tester. This method is a road spectrum data processing method based on a high dynamic durability tester. It can analyze only unreasonable data and retain the working signals of the drive shaft (swing angle, speed, torque, vertical vibration, etc.) in the road spectrum to the greatest extent.

[0010] The present invention adopts the following technical solution.

[0011] A data processing method based on a road spectrum bench tester is provided. The method is used to process the working signal data of the drive shaft and the processed drive shaft signal data related to the acquisition frequency during road testing. The processing process analyzes unreasonable data and retains the working signal of the drive shaft in the road spectrum data by ignoring reasonable data during the processing.

[0012] The method is as follows: First, find the data that exceeds the device's allowable range. Then, calculate the average of the data that exceeds the device's allowable range and the data at the next moment. If the average value is within the device's allowable range, calculate the average value of the data that exceeds the device's allowable range and the data at the next moment. If the average value is not within the device's allowable range, continue to calculate the average value downwards until the average value is within the device's allowable range, and then output it.

[0013] The drive shaft is a drive shaft component in an automotive drive shaft system, and its operating signal data includes sway angle, rotational speed, torque, and vertical vibration.

[0014] The unreasonable data is manually set according to the permissible operating conditions of the durability testing machine, so that the data processed by this method is the final data that meets the permissible operating conditions of the durability testing machine.

[0015] The working signal data of the drive shaft is a sequence formed by the sampling time and the values ​​of each working signal at that time point. The sampling interval between each value in the sequence is 0.01 seconds. The limit range of the allowable torque M of the drive shaft device is -4000Nm≤M≤4000Nm, and the limit range of the allowable torque change rate Ms is -600Nm / s≤Ms≤600Nm / s.

[0016] The method only processes torque M and torque change rate Ms that exceed the limit range.

[0017] In the method described, if the torque exceeds the allowable limit of the equipment but the excess is negligible, the torque is adjusted to the upper or lower limit of the limit range. When calculating an unreasonable torque change rate Ms, the torque acceleration during that period is calculated using the provided time and torque information, and the calculation formula is as follows:

[0018] Formula 1;

[0019] In the formula, The rate of change of torque; Torque; For time; The sequence number is used to calculate the rate of change of torque for each group in the sequence.

[0020] The downward averaging method includes the following steps:

[0021] Process A1 Starting from 2, increment sequentially. If the value is within the device's allowed range, output that value.

[0022] Process A2, if in process A1, If the corresponding value is not within the allowed range of the device, then locate the next digit of the data corresponding to the next sequence number and calculate the average with the next digit of the data;

[0023] If the calculation result of process A3 is not within the range, it will not be output. The calculation will continue to be averaged downwards until the calculation result is within the range, and then the average value will be output uniformly.

[0024] In process A1, if If it is 2, then Then proceed to process the data corresponding to the next sequence number.

[0025] In process A2, if at this time... The original value was 3, so it is changed to 4. That is, if the calculation result is within the allowable range of the device, then output it;

[0026] In process A3, take It is 5. If the calculated result is still outside the range, then take... It is 6. If the calculation result is still outside the range at this point, then take... If the result is 7, continue calculating, and so on, until the result meets the allowable range of the equipment.

[0027] The method outputs drive shaft operating data from road tests using processes A1, A2, and A3. When it is necessary to verify the output values ​​of each process, the following formula is used for verification.

[0028]

[0029] In the formula, The rate of change of torque; Torque; For time; Using the sequence number as the index, the rate of change of torque in each group in the sequence is calculated sequentially.

[0030] This invention processes the raw data from road tests using a downward averaging method, and the data processed by this method can meet the equipment's permissible operating limits.

[0031] In the process of processing, this invention retains as much data as possible that meets the operating limits allowed by the equipment.

[0032] The beneficial effects of this invention also include:

[0033] 1. The data processed by this method of the present invention can meet the allowable operating limits of the equipment to the greatest extent, and the given data variation can be appropriately adjusted according to the actual working conditions of the drive shaft. (For example, if the equipment's rotational speed range is ±2500 rpm and the acceleration of the rotational speed is ±500 rpm / s, then when processing the rotational speed data, the upper and lower limits of the data can be adjusted to ±2500, and the data variation rate can be adjusted to ±500). This avoids the need for data filtering, and therefore eliminates the need to spend a significant amount of time finding the filtering frequency.

[0034] 2. This invention analyzes only the data where the equipment does not meet the permissible operating limits, and processes it using a downward averaging method. This avoids the uncertainty of the amount of data processed by filtering, and compared to simple filtering, it can restore the working conditions of the drive shaft in the test field to the greatest extent. It avoids large-area distortion in filtering. Attached Figure Description

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0036] Appendix Figure 1 This is a schematic flowchart of the downward averaging method of the present invention;

[0037] Appendix Figure 2 This is a schematic diagram of data processing for equipment limits under operating conditions, according to the present invention. Detailed Implementation

[0038] As shown in the figure, a data processing method based on a road spectrum bench tester is described. The method is used to process the working signal data of the drive shaft and the processing drive shaft signal data related to the acquisition frequency during road testing. The processing process analyzes unreasonable data and retains the working signal of the drive shaft in the road spectrum data by ignoring reasonable data during the processing.

[0039] The method is as follows: First, find the data that exceeds the device's allowable range. Then, calculate the average of the data that exceeds the device's allowable range and the data at the next moment. If the average value is within the device's allowable range, calculate the average value of the data that exceeds the device's allowable range and the data at the next moment. If the average value is not within the device's allowable range, continue to calculate the average value downwards until the average value is within the device's allowable range, and then output it.

[0040] The drive shaft is a drive shaft component in an automotive drive shaft system, and its operating signal data includes sway angle, rotational speed, torque, and vertical vibration.

[0041] The unreasonable data is manually set according to the permissible operating conditions of the durability testing machine, so that the data processed by this method is the final data that meets the permissible operating conditions of the durability testing machine.

[0042] The working signal data of the drive shaft is a sequence formed by the sampling time and the values ​​of each working signal at that time point. The sampling interval between each value in the sequence is 0.01 seconds. The limit range of the allowable torque M of the drive shaft device is -4000Nm≤M≤4000Nm, and the limit range of the allowable torque change rate Ms is -600Nm / s≤Ms≤600Nm / s.

[0043] The method only processes torque M and torque change rate Ms that exceed the limit range.

[0044] In the method described, such as Figure 2 As shown, if the torque exceeds the equipment's allowable limit range but the excess is negligible, the torque will be adjusted to the upper or lower limit of the limit range. When calculating an unreasonable torque change rate Ms, the torque acceleration during that period is calculated using the provided time and torque information, using the following formula:

[0045] Formula 1;

[0046] In the formula, The rate of change of torque; Torque; For time; The sequence number is used to calculate the rate of change of torque for each group in the sequence.

[0047] The downward averaging method includes the following steps:

[0048] Process A1 Starting from 2, increment sequentially. If the value is within the device's allowed range, output that value.

[0049] Process A2, if in process A1, If the corresponding value is not within the allowed range of the device, then locate the next digit of the data corresponding to the next sequence number and calculate the average with the next digit of the data;

[0050] If the calculation result of process A3 is not within the range, it will not be output. The calculation will continue to be averaged downwards until the calculation result is within the range, and then the average value will be output uniformly.

[0051] In process A1, if If it is 2, then Then proceed to process the data corresponding to the next sequence number.

[0052] In process A2, if at this time... The original value was 3, so it is changed to 4. That is, if the calculation result is within the allowable range of the device, then output it;

[0053] In process A3, take It is 5. If the calculated result is still outside the range, then take... It is 6. If the calculation result is still outside the range at this point, then take... If the result is 7, continue calculating, and so on, until the result meets the allowable range of the equipment.

[0054] The method outputs drive shaft operating data from road tests using processes A1, A2, and A3. When it is necessary to verify the output values ​​of each process, the following formula is used for verification.

[0055]

[0056] In the formula, The rate of change of torque; Torque; For time; Using the sequence number as the index, the rate of change of torque in each group in the sequence is calculated sequentially.

[0057] Example:

[0058] This example provides a method for processing drive shaft signals based on the relationship between the drive shaft's operating signals (swing angle, speed, torque, vertical vibration, etc.) and the acquisition frequency during road testing. Unlike traditional filtering methods, the downward averaging method in this invention can analyze only unreasonable data, preserving the required drive shaft operating signals (swing angle, speed, torque, vertical vibration, etc.) in the road spectrum to the greatest extent possible. Furthermore, finding unreasonable data only requires engineers to set the parameters according to the permissible operating conditions of the durability testing machine, without extensive adjustments and trials. This not only significantly reduces the difficulty of data processing, but also ensures that the data processed using this method is the final data that meets the permissible operating conditions of the durability testing machine.

[0059] The specific method is as follows: Figure 1 As shown, the process first identifies data that exceeds the device's allowable range. It then calculates the average of this data with the data from the next time step. If the average is within the device's allowable range, the average of the data exceeding the allowable range and the data from the next time step is output. If it is not within the device's allowable range, the process continues calculating the average until it falls within the device's allowable range, at which point it is output.

[0060] In this example, the test track typically only provides the sampling time and the values ​​of each working signal at that time point for the drive shaft's operating signals (sway angle, speed, torque, vertical vibration, etc.) during road testing.

[0061] This example uses torque data provided by a test track. A 0.01-second segment is extracted for processing. A schematic diagram illustrating the raw road spectrum data is shown in Table 1 below.

[0062]

[0063] As shown in the table above, M1 is 4001 Nm, which exceeds the equipment's limit. However, due to strict power limitations in the experiment, this is only a slight exceedance. Therefore, it is adjusted to the equipment's limit (-4000 ≤ M ≤ 4000). All other data are within the equipment's allowable range, so no further adjustments are made. The adjusted data are shown in Table 2.

[0064]

[0065] When calculating the rate of change of torque, the torque acceleration during that time period is calculated using the provided time and torque information. The calculation formula is as follows:

[0066]

[0067] In the formula, The rate of change of torque; Torque; For time; The numbers represent the sequence. Ten sets of torque change rates were calculated sequentially. The calculated data is illustrated in Table 3 below.

[0068]

[0069] The calculated data shows that when the torque values ​​are 3, 4, and 5, the torque change rates are -667.7, -701.6, and -617.1, respectively. These exceed the equipment's limit condition of -600≤Ms≤600. Therefore, a downward averaging method needs to be used for processing.

[0070] The processing flow for the downward averaging method is as follows: Figure 1 , Starting from 2, increment sequentially. If the value is within the device's allowed range, output that value. If it is outside the equipment's allowable range, The average value is calculated by averaging the result with the next digit. If the result is within the range, it is output; otherwise, the average is continued downwards. Finally, the average value is output as the final value. The detailed processing flow is as follows:

[0071] 1. When When the value is 2, Ms = -407.2 (-600 ≤ Ms ≤ 600), so the output is -407.2 directly.

[0072]

[0073]

[0074] 2. When When the value is 3, the Ms value is -667.7 (< -600), so no output is given. Averaging downwards:

[0075]

[0076]

[0077] In the formula, n is taken as 4.

[0078] 3. The processed Ms3=Ms4=-684.65 (<-600), so no output is given. Averaging downwards is performed:

[0079]

[0080]

[0081] In the formula, n is taken as 5.

[0082] 4. The processed Ms3=Ms4=Ms5=-662.13 (<-600), no output. Averaging downwards:

[0083]

[0084]

[0085] In the formula, n is taken as 6.

[0086] 5. The processed Ms3=Ms4=Ms5=Ms6=-604.375 (<-600), no output. Averaging downwards:

[0087]

[0088]

[0089] In the formula, n is taken as 7.

[0090] 6. The processed Ms3=Ms4=Ms5=Ms6=Ms7=-525.76 (-600≤Ms≤600), therefore .

[0091]

[0092]

[0093] 7. When When the value is 8, Ms = 16.9 (-600≤Ms≤600), so the output is 16.9 directly.

[0094]

[0095]

[0096] 8. When When the value is 9, Ms = 169 (-600 ≤ Ms ≤ 600), so the output is 169 directly.

[0097]

[0098]

[0099] 9. When When the value is 10, Ms = 236.7 (-600≤Ms≤600), so the output is 236.7 directly.

[0100]

[0101]

[0102] Table 4 below shows a schematic diagram of the road spectrum data before and after processing:

[0103]

[0104] To demonstrate the effectiveness of data processing, the data is brought back to the experimental parameters.

[0105] The calculation formula is as follows:

[0106]

[0107] In the formula, The rate of change of torque; Torque; For time; The numbers represent the sequence. Ten sets of torque change rates were calculated sequentially. The calculated data is illustrated in Table 3 below.

[0108] Ten sets of torques were calculated sequentially. The calculated data is illustrated in Table 5 below:

[0109]

[0110] (In Table 5, red marks indicate that the equipment cannot meet the requirements. Blue marks indicate the figures after averaging downwards. Yellow marks indicate that the torques are equalized again.)

[0111] As can be seen from the table above, within the 0.1-second timeframe from 161.49 to 161.58, only the values ​​for n=3, 4, and 5 exceeded the equipment limits. The downward averaging method not only brought the torque acceleration within the equipment's operating range, but also ensured that 6 out of 10 data sets matched the original road spectrum, maximizing the preservation of the original data. This allows the processed data, while meeting the equipment's operating conditions, to fully reproduce the drive shaft's working condition during road testing.

Claims

1. A data processing method based on a road spectrum bench testing machine, characterized in that: The method is used to process the working signal data of the drive shaft and the processing drive shaft signal data related to the acquisition frequency during road testing. The processing process analyzes unreasonable data and retains the working signal of the drive shaft in the road spectrum data by ignoring reasonable data during the processing. The method includes a downward averaging method. First, data exceeding the device's allowable range is identified. This data is then averaged with the data at the next time step. If the resulting average is within the device's allowable range, the average is calculated again and output. If it is not within the device's allowable range, the average is calculated downwards until it falls within the device's allowable range, at which point it is output. Specifically: In the method described, if the torque exceeds the equipment's permissible limit but the excess is negligible, the torque is adjusted to the upper or lower limit of the limit range. When calculating an unreasonable torque change rate Ms, the torque change rate during the road test period is calculated using the provided time and torque information, and the calculation formula is as follows: Formula 1; In the formula, The rate of change of torque; Torque; For time; The sequence number is used to calculate the rate of change of torque for each group in the sequence. The downward averaging method includes the following steps: Procedure A1, From 2, increase sequentially, if the torque change rate is within the range allowed by the device, output the value; Process A2, if in process A1, If the corresponding torque change rate is not within the allowable range of the equipment, then locate the next data corresponding to the next sequence number and average it with the next data. Process A3: If the calculation result of Process A2 is not within the range, no output will be given. Continue to calculate the average value downwards until the torque change rate is within the range, and then output the average value. In flow A1, if is 2, then ; and then turn to the next sequence number corresponding to the processing of the speed of torque change; In process A2, if at this time... The original value was 3, so it is changed to 4. That is, if the rate of change of torque is within the allowable range of the equipment, then output; In flow A3, take 5, If the torque change rate is still not in the range, take 6, If the torque change rate is still not in the range, take 7, Continue to calculate, and so on until the torque change rate meets the device allowable range.

2. The data processing method based on a road spectrum bench tester according to claim 1, characterized in that: The drive shaft is a drive shaft component in an automotive drive shaft system, and its operating signal data includes any one of the following: sway angle, rotational speed, torque, and vertical vibration.

3. The data processing method based on the road spectrum bench tester according to claim 1, characterized in that: The unreasonable data is manually set according to the permissible operating conditions of the durability testing machine, so that the data processed by this method is the final data that meets the permissible operating conditions of the durability testing machine.

4. The data processing method based on a road spectrum bench testing machine according to claim 1, characterized in that: The working signal data of the drive shaft is a sequence formed by the sampling time and the values ​​of each working signal at the sampling time point. The sampling interval between each value in the sequence is 0.01 seconds. The limit range of the allowable torque M of the drive shaft device is -4000Nm≤M≤4000Nm, and the limit range of the allowable torque change rate Ms is -600Nm / s≤Ms≤600Nm / s. The method only processes torque M and torque change rate Ms that exceed the limit range.

5. The data processing method based on a road spectrum bench tester according to claim 1, characterized in that: The method outputs drive shaft operating data from road tests using processes A1, A2, and A3. When it is necessary to verify the output values ​​of each process, the following formula is used for verification. In the formula, The rate of change of torque; Torque; For time; Using the sequence number as the index, the rate of change of torque in each group in the sequence is calculated sequentially.

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