A method and system for processing gearbox impact vibration problems during vehicle acceleration and deceleration

Abstract

This invention discloses a method and system for handling gearbox impact vibration problems during vehicle acceleration and deceleration. The method includes the following steps: conducting whole-vehicle testing to obtain vibration parameter information, state parameter information, and a whole-vehicle NVH score when gearbox impact vibration occurs; obtaining evaluation parameters based on the vibration parameter information; establishing the relationship between the evaluation parameters and the whole-vehicle NVH score; establishing the relationship between the evaluation parameters and the state parameters based on the state parameter information; and optimizing the vehicle design to adjust the state parameters based on the relationship between the evaluation parameters and the whole-vehicle NVH score, as well as the relationship between the evaluation parameters and the state parameters, thereby achieving the required whole-vehicle NVH score. This method enables objective and efficient gearbox impact assessment, analysis, and verification, guides further optimization of gear impact, reduces the number of NVH tests, and shortens the development cycle.

Description

Technical Field

[0001] This invention relates to the field of gearbox technology, specifically to a method and system for handling gearbox impact vibration problems during vehicle acceleration and deceleration. Background Technology

[0002] The gearbox is a crucial component of a vehicle's transmission system, serving functions such as regulating speed, changing transmission direction, and altering transmission torque. During both coasting-acceleration and acceleration-coasting operations, gearboxes commonly experience gear impact vibration and noise due to the switching of gear meshing clearance or meshing surfaces. Existing analyses of this problem only qualitatively describe the characteristics of gear impact: whether impact is present or absent. Objective assessment parameters for the severity of impact vibration are either undefined or very coarse, and no research has been established on the relationship between the severity of gear impact and relevant key parameters. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method and system for handling gearbox impact and vibration problems during vehicle acceleration and deceleration, which can objectively and efficiently perform gear impact assessment and analysis, and guide further optimization of gear impact.

[0004] To address the aforementioned technical problems, this invention provides a method for handling gearbox impact and vibration during vehicle acceleration and deceleration, comprising the following steps:

[0005] Step 1: Conduct a full vehicle test to obtain vibration parameters, state parameters, and overall vehicle NVH score when gear impact vibration occurs in the gearbox;

[0006] Step 2: Obtain evaluation parameters based on vibration parameter information;

[0007] Step 3: Establish the relationship between evaluation parameters and vehicle NVH score;

[0008] Step 4: Based on the state parameter information, establish the relationship between the evaluation parameters and the state parameters;

[0009] Step 5: Based on the relationship between the evaluation parameters and the overall vehicle NVH score, as well as the relationship between the evaluation parameters and the condition parameters, optimize the vehicle design to adjust the condition parameters, thereby ensuring that the overall vehicle NVH score meets the standards.

[0010] Furthermore, the vibration parameter information includes the relationship between the vibration acceleration of the gearbox and time. Step two includes:

[0011] Step b1: Obtain the maximum value of the vibration acceleration amplitude and the corresponding moment when the amplitude is at its maximum;

[0012] Step b2: Before obtaining the moment of maximum amplitude, set the root mean square value of vibration acceleration within the time interval, and record it as the left root mean square value;

[0013] Step b3: After obtaining the moment of maximum amplitude, set the root mean square value of vibration acceleration within the time interval, and record it as the right root mean square value;

[0014] Step b4: Calculate the evaluation parameters based on the maximum value, the left root mean square value, and the right root mean square value.

[0015] Furthermore, step five includes:

[0016] Step c1: Based on the relationship between the evaluation parameters and the vehicle NVH score, determine the evaluation parameter limits corresponding to the critical acceptable value when the vehicle NVH score is reached.

[0017] Step c2: Based on the relationship between the evaluation parameters and the state parameters, determine the optimal design of the vehicle to make the evaluation parameters less than the limit, so that the state parameters can be adjusted, thereby making the overall vehicle NVH score meet the standard.

[0018] In the aforementioned method for handling gearbox impact and vibration issues during vehicle acceleration and deceleration, objective evaluation parameters are created using vibration parameter information. A relationship is established between these evaluation parameters and the overall vehicle NVH score caused by gear impact. Then, target values ​​for the evaluation parameters are set based on the overall vehicle NVH score. Finally, the relationship between the evaluation parameters and state parameters guides the calibration and improvement work on the test bench and the entire vehicle regarding gear impact, optimizing vehicle performance design and reducing the evaluation parameters to below the target values, thus achieving optimization of the overall vehicle NVH score. The relationship between the evaluation parameters and state parameters enables objective and efficient gearbox impact evaluation, analysis, and verification, guiding further optimization of gear impact, reducing the number of NVH tests, and shortening the development cycle.

[0019] To solve the above-mentioned technical problems, the present invention provides a system based on the above-mentioned method for handling gearbox impact and vibration problems during vehicle acceleration and deceleration, comprising:

[0020] The calculation module is used to obtain evaluation parameters based on vibration parameter information;

[0021] The first module is used to establish the relationship between evaluation parameters and the vehicle's NVH score.

[0022] The second module is used to establish the relationship between the evaluation parameters and the state parameters based on the state parameter information.

[0023] The output module is used to output a vehicle optimization design based on the relationship between the evaluation parameters and the overall vehicle NVH score, as well as the relationship between the evaluation parameters and the state parameters, so as to adjust the state parameters and thus make the overall vehicle NVH score meet the standards.

[0024] Furthermore, the system also includes an input module for inputting vibration parameter information, state parameter information, and vehicle NVH score when the gearbox experiences gear impact vibration during vehicle testing.

[0025] Furthermore, the system also includes a testing system for conducting whole-vehicle testing, acquiring vibration parameter information, state parameter information, and whole-vehicle NVH score when the gearbox experiences gear impact vibration.

[0026] In summary, the above-mentioned method and system for handling gearbox impact and vibration during vehicle acceleration and deceleration can objectively and efficiently evaluate and analyze gearbox impact, and guide further optimization of gear impact. Attached Figure Description

[0027] In the attached diagram:

[0028] Figure 1 This is a flowchart of the method for handling gearbox impact and vibration problems during vehicle acceleration and deceleration according to the present invention.

[0029] Figure 2 This is a regression model diagram of SN and the overall vehicle NVH score.

[0030] Figure 3 It is the measured vibration acceleration signal from a certain test of the gearbox.

[0031] Figure 4 This is a structural diagram of the gearbox impact and vibration problem handling system of the present invention during vehicle acceleration and deceleration. Detailed Implementation

[0032] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings. It should be noted that these descriptions of the embodiments are for the purpose of helping to understand the present invention, but do not constitute a limitation thereof.

[0033] Example 1

[0034] Figure 1 This invention illustrates a method for addressing gearbox impact and vibration problems during vehicle acceleration and deceleration. The method includes the following steps:

[0035] Step S10: Conduct a full vehicle test to obtain vibration parameters, state parameters, and the overall vehicle NVH score when gearbox experiences gear impact vibration. Optional steps include:

[0036] Step a1: Develop a test condition table for the entire vehicle. Bench tests can be conducted in a laboratory, or real-vehicle tests can be performed on a smooth asphalt road in a relatively quiet environment. Microphone sensors are placed at the driver's ears inside the vehicle. The test condition table includes the input speed, input torque, and vehicle speed of the gearbox. Two operating conditions are defined as two vehicle driving states that cause gear impact vibration in the gearbox: coasting followed by acceleration and acceleration followed by coasting, as detailed in Table 1. Furthermore, the gearbox speed and torque mentioned below refer to input torque and speed.

[0037] The first operating condition is the acceleration condition after coasting, defined as follows: engine speeds of 10 km / h, 20 km / h, 30 km / h, 40 km / h, 50 km / h, and 60 km / h; torque (defined as the torque provided to the gearbox at a specific throttle opening) of 10%, 30%, and 50%. The specific testing procedures are as follows: ① Controlling the vehicle to coast at 10 km / h, accelerating with a 10% throttle opening; ② Controlling the vehicle to coast at 10 km / h, accelerating with a 30% throttle opening; ...; ④ Controlling the vehicle to coast at 20 km / h, accelerating with a 10% throttle opening; ...

[0038] The second operating condition, acceleration followed by coasting, is defined as follows: engine speeds of 10 km / h, 20 km / h, 30 km / h, 40 km / h, 50 km / h, and 60 km / h, with torque reductions of -10% and -30%. The specific testing procedures are as follows:

[0039] For real-vehicle testing: ① Control the vehicle to accelerate, and when the speed reaches 10km / h, release the accelerator and coast; ② Control the vehicle to accelerate, and when the speed reaches 20km / h, release the accelerator and coast...

[0040] For bench testing: ① Control the vehicle to accelerate, and brake at 10 km / h with a braking force of 10% of the gearbox's maximum torque; ② Control the vehicle to accelerate, and brake at 10 km / h with a braking force of 30% of the gearbox's maximum torque; ③ Control the vehicle to accelerate, and brake at 20 km / h with a braking force of 10% of the gearbox's maximum torque...

[0041] Table 1 Operating Conditions Table

[0042]

[0043] Step a2: Deploy data acquisition equipment. A vibration acceleration sensor is deployed at the gearbox reference point to acquire vibration parameters when gear impact vibration occurs in the gearbox; microphone sensors are deployed at the driver's ears inside the vehicle to acquire noise parameters; status parameters, such as torque and speed, can be directly read from the vehicle's controller.

[0044] There are two methods to obtain the NVH score of a vehicle: ① By designing an NVH evaluation device, receiving noise parameter information and vibration parameter information, comparing them with the corresponding preset threshold ranges, and outputting the NVH score; ② By having test personnel trained in NVH scoring record the scores during testing.

[0045] Step a3: Perform the vehicle test according to the vehicle test condition table, causing gear impact vibration in the gearbox, and simultaneously obtain vibration parameter information, state parameter information, and vehicle NVH score. Perform the test in sequence to obtain the information on the change of each parameter over time.

[0046] Step S20: Obtain evaluation parameters based on vibration parameter information. Vibration parameter information includes the relationship between the gearbox's vibration acceleration and time. Optionally, the X-axis vibration acceleration, i.e., the vibration in the vehicle's longitudinal direction, is taken as the data acquisition object, as X-axis vibration has a significant impact on humans. Step two specifically includes:

[0047] Step b1: Obtain the maximum value of the vibration acceleration amplitude, denoted as MAX, and the time corresponding to the maximum amplitude, denoted as t1.

[0048] Step b2: Before obtaining the moment t1 when the amplitude is at its maximum, set the root mean square value of the vibration acceleration within the time interval Δt, and record it as the left root mean square value RMS. L It represents the average vibration acceleration before the occurrence of impact vibration.

[0049] Step b3: After obtaining the moment t1 when the amplitude is at its maximum, set the root mean square value of the vibration acceleration within the time interval Δt, and record it as the right-hand root mean square value RMS. R It characterizes the vibration acceleration after the impact vibration occurs.

[0050] Step b4: Calculate the evaluation parameter, denoted as SN, based on the maximum value, the left root mean square value, and the right root mean square value. The calculation formula is:

[0051]

[0052] In the formula, (RMS L +RMS R The ratio ) / 2 represents the average vibration acceleration before and after the impact vibration. The evaluation parameter is calculated by using the ratio of the acceleration amplitude during the impact vibration to the amplitude before and after the impact vibration. It can reflect the magnitude of the impact vibration and has great representativeness.

[0053] like Figure 3 As shown, the root mean square (RMS) value on the left side L The values ​​are calculated within the time interval Δt = 0.08, within 0.1 s before time t1, with the optimal range being 0.1 s to 0.02 s before time t1; the root mean square value (RMS) on the right side is also considered. RThe optimal timeframe is 0.02 to 0.1 seconds after time t1, calculated within the time interval of Δt = 0.08.

[0054] Step S30: Establish the relationship between the evaluation parameters and the vehicle NVH score. Optionally, establish a regression model between the evaluation parameters and the corresponding vehicle NVH score, typically a univariate linear regression equation, such as... Figure 2 As shown.

[0055] Step S40: Establish the relationship between the evaluation parameters and the state parameters based on the state parameter information. The state parameter information includes the gearbox's rotational speed over time, torque over time, and throttle opening over time, etc., and this information is acquired during the test, as described in step S10.

[0056] Optionally, step four specifically includes: establishing a regression model between the evaluation parameters and multiple state parameters, using each state parameter to characterize the evaluation parameters, and the evaluation parameters are related to the vehicle NVH score. Therefore, the evaluation parameters are used as a bridge to connect the state parameters and the vehicle NVH score.

[0057] Optionally, a regression model can be established between the evaluation parameters and the impact vibration time, starting speed, ending speed, starting torque, and ending torque. Here, the starting speed and starting torque refer to the corresponding values ​​at the starting time, the starting time refers to the time when the throttle opening state is switched, the ending speed and ending torque refer to the corresponding values ​​at the ending time, the ending time refers to the time when the impact vibration occurs, and the impact vibration time is the time span between the starting time and the ending time.

[0058] Taking a gearbox as an example, during the project development phase, there was a problem of gear impact vibration and noise when accelerating after the vehicle coasts. Based on theory and project experience, the following parameters with strong correlation to the impact vibration were determined: the time from the start of speed increase (acceleration) to the occurrence of gear impact: T1→T2; impact speed: speed n1 at time T1 and speed n2 at time T2; torque: torque F1 at time T1 and speed n2 at time F2, etc. The important parameters and SN results from all test samples are summarized in Table 2 and imported into Minitab to fit a regression model. Then, the function of the fitted regression model is extracted as follows:

[0059] SN=29.63-16.0*ΔT-0.1349*n1+0.1277*n2-0.0483*F1+0.414*F2;

[0060] Table 2 Summary of Important Parameters and SN Results in the Test Sample

[0061]

[0062] Optionally, a verification step is also included: based on the SN calculation formula obtained above, verify the gear impact performance of subsequent samples, mainly including comparing the predicted results with the measured results, as shown in Table 3, and determining the accuracy of the evaluation parameters and state parameter regression model. When the predicted SN deviates from the actual value by more than 8%, the regression model needs to be refitted.

[0063] Table 3 Summary of key parameters and SN results in the validation sample

[0064]

[0065] Step S50: Based on the relationship between the evaluation parameters and the overall vehicle NVH score, and the relationship between the evaluation parameters and the state parameters, optimize the vehicle design to adjust the state parameters, thereby ensuring the overall vehicle NVH score meets the standards. Optionally, taking the aforementioned gearbox as an example, the specific steps include:

[0066] Step c1: Based on the relationship between the evaluation parameters and the vehicle NVH score, determine the evaluation parameter limits corresponding to the critical acceptable value when the vehicle NVH score is reached. According to... Figure 2 The evaluation parameters shown are used in the regression model of the whole vehicle NVH score. Based on the bench and whole vehicle test results, the SN value of 25 is defined as the target value, that is, the critical acceptable SN limit is 25, and the score is 7.0.

[0067] Step c2: Based on the relationship between the evaluation parameters and the state parameters, determine the optimal design of the vehicle to make the evaluation parameters less than the limit, so that the state parameters can be adjusted, thereby making the overall vehicle NVH score meet the standard.

[0068] Furthermore, based on the regression model of the evaluation parameters and multiple state parameters: SN=29.63-16.0*ΔT-0.1349*n1+0.1277*n2-0.0483*F1+0.414*F2, the adjustment priority can be sorted according to the absolute value of each state parameter coefficient. The larger the absolute value of the coefficient, the greater its contribution to the vibration, and the more priority it should be adjusted, resulting in better adjustment effects.

[0069] Calibration and optimization are performed on the whole vehicle or bench to target parameters highly relevant to gear impact. Vehicle optimization design can include: reducing throttle response rate, decreasing the slope of speed and torque increase, etc. If the predicted SN value is below 25 after improvement, then the relatively large gear impact performance may be acceptable. This approach can reduce the number of NVH tests and shorten the development cycle.

[0070] like Figure 4As shown, the present invention discloses a system for handling gearbox impact vibration problems during vehicle acceleration and deceleration, comprising: a calculation module 1 for obtaining evaluation parameters based on vibration parameter information; a first establishment module 2 for establishing the relationship between the evaluation parameters and the overall vehicle NVH score; a second establishment module 3 for establishing the relationship between the evaluation parameters and the state parameters based on state parameter information; and an output module 4 for outputting an optimized vehicle design that adjusts the state parameters to achieve the desired overall vehicle NVH score, based on the relationship between the evaluation parameters and the overall vehicle NVH score, and the relationship between the evaluation parameters and the state parameters.

[0071] Optionally, the system also includes an input module 5, which is used to input vibration parameter information, state parameter information and vehicle NVH score when the gearbox experiences gear impact vibration during vehicle testing.

[0072] Optionally, the system also includes a testing system 6 for conducting whole vehicle testing, acquiring vibration parameter information, state parameter information, and whole vehicle NVH score when gearbox experiences gear impact vibration.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit its scope of protection. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading the present invention, they can still make various changes, modifications or equivalent substitutions to the specific implementation of the invention, but these changes, modifications or equivalent substitutions are all within the scope of protection of the pending claims of the invention.

Claims

1. A method for handling gearbox impact and vibration problems during vehicle acceleration and deceleration, characterized in that, Includes the following steps: Step 1: Conduct a full vehicle test to obtain vibration parameters, state parameters, and overall vehicle NVH score when gear impact vibration occurs in the gearbox; Step 2: Obtain evaluation parameters based on vibration parameter information; Step 3: Establish the relationship between evaluation parameters and vehicle NVH score; Step 4: Based on the state parameter information, establish the relationship between the evaluation parameters and the state parameters; Step 5: Based on the relationship between the evaluation parameters and the overall vehicle NVH score, as well as the relationship between the evaluation parameters and the condition parameters, optimize the vehicle design to adjust the condition parameters, thereby ensuring that the overall vehicle NVH score meets the standards.

2. The method for handling gearbox impact vibration during vehicle acceleration and deceleration according to claim 1, characterized in that, Step one includes: Step a1: Develop a complete vehicle test condition table; Step a2: Deploy data acquisition equipment; Step a3: Perform the vehicle test according to the vehicle test condition table, causing gear impact vibration in the gearbox, and simultaneously obtain vibration parameter information, state parameter information, and vehicle NVH score.

3. The method for handling gearbox impact vibration during vehicle acceleration and deceleration according to claim 1, characterized in that, Vibration parameter information includes the relationship between the vibration acceleration of the gearbox and time. Step two includes: Step b1: Obtain the maximum value of the vibration acceleration amplitude and the corresponding moment when the amplitude is at its maximum; Step b2: Before obtaining the moment of maximum amplitude, set the root mean square value of vibration acceleration within the time interval, and record it as the left root mean square value; Step b3: After obtaining the moment of maximum amplitude, set the root mean square value of vibration acceleration within the time interval, and record it as the right root mean square value; Step b4: Calculate the evaluation parameters based on the maximum value, the left root mean square value, and the right root mean square value.

4. The method for handling gearbox impact vibration during vehicle acceleration and deceleration according to claim 1, characterized in that, Step three includes: establishing a regression model between the evaluation parameters and the corresponding vehicle NVH score.

5. A method for handling gearbox impact vibration during vehicle acceleration and deceleration according to claim 1, characterized in that, The state parameter information includes the relationship between the gearbox's rotational speed and time, the relationship between torque and time, and the relationship between throttle opening and time. Step four includes: establishing a regression model between the evaluation parameters and multiple state parameters.

6. A method for handling gearbox impact vibration during vehicle acceleration and deceleration according to claim 5, characterized in that, Step four includes: establishing a regression model of the evaluation parameters and the impact vibration time, starting speed, ending speed, starting torque, and ending torque, wherein the starting speed and starting torque refer to the corresponding values ​​at the starting time, the starting time refers to the time when the throttle opening state is switched, the ending speed and ending torque refer to the corresponding values ​​at the ending time, the ending time refers to the time when the impact vibration occurs, and the impact vibration time is the time span between the starting time and the ending time.

7. A method for handling gearbox impact vibration during vehicle acceleration and deceleration according to claim 1, characterized in that, Step five includes: Step c1: Based on the relationship between the evaluation parameters and the vehicle NVH score, determine the evaluation parameter limits corresponding to the critical acceptable value when the vehicle NVH score is reached. Step c2: Based on the relationship between the evaluation parameters and the state parameters, determine the optimal design of the vehicle to make the evaluation parameters less than the limit, so that the state parameters can be adjusted, thereby making the overall vehicle NVH score meet the standard.

8. A system for handling gearbox impact and vibration problems during vehicle acceleration and deceleration according to any one of claims 1-7, characterized in that, include: The calculation module (1) is used to obtain evaluation parameters based on vibration parameter information; The first module (2) is used to establish the relationship between the evaluation parameters and the vehicle NVH score; The second module (3) is used to establish the relationship between the evaluation parameters and the state parameters based on the state parameter information. The output module (4) is used to output a vehicle optimization design that adjusts the state parameters and makes the vehicle NVH score meet the standard, based on the relationship between the evaluation parameters and the vehicle NVH score, and the relationship between the evaluation parameters and the state parameters.

9. The system according to claim 8, characterized in that, It also includes an input module (5) for inputting vibration parameter information, state parameter information and vehicle NVH score when the gearbox experiences gear impact vibration during vehicle testing.

10. The system according to claim 8, characterized in that, It also includes a testing system (6) for conducting whole vehicle testing, obtaining vibration parameter information, state parameter information and whole vehicle NVH score when gearbox experiences gear impact vibration.

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