A test system for the unbalanced mass tolerance value of vehicle steering wheel shimmy

Abstract

The present invention discloses a system for testing the unbalanced mass tolerance value for vehicle steering wheel shimmy. The system comprises: a controller, a steering wheel acceleration sensor connected to the controller; a steering wheel acceleration sensor for pasting different numerical mass blocks at a designated position of a front wheel of the vehicle, respectively testing the steering wheel acceleration of each mass block in a test cycle, and transmitting the steering wheel acceleration to the controller; a controller for obtaining the minimum numerical mass block corresponding to the maximum steering wheel circumferential vibration acceleration being greater than or equal to a preset threshold, and using the minimum numerical mass block as the unbalanced mass tolerance value corresponding to the vehicle steering wheel shimmy. By pasting mass blocks at designated positions of the wheels, the tolerance value of the steering wheel shimmy to the wheel edge unbalanced mass can be measured, which is used as a robustness evaluation index for the vehicle steering wheel shimmy, and provides a basis for subsequent vehicle steering wheel shimmy optimization design and evaluation work.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle testing, and in particular to a system for testing an unbalanced mass tolerance value for vehicle steering wheel shimmy. Background Art

[0002] A vehicle's steering wheel shimmy refers to the perceptible circumferential vibration of the steering wheel when the vehicle is driving in a straight line on a flat road. The circumferential vibration of the steering wheel is visible when the steering wheel is released. With the rapid development of automobiles, people's requirements for vehicle ride comfort are constantly increasing, and their attention to vibration problems such as steering wheel shimmy is gradually increasing.

[0003] The current research direction for steering wheel shimmy is mainly how to identify or evaluate the steering wheel shimmy when the vehicle shimmies, and how to reduce the steering wheel shimmy based on the identification or evaluation results.

[0004] However, the research direction of steering wheel shimmy in the prior art is relatively single, mainly targeting vehicles that have experienced steering wheel shimmy. However, robustness evaluation of steering wheel shimmy of normal vehicles is also an issue that urgently needs to be studied. Summary of the invention

[0005] The invention provides an unbalanced mass tolerance value testing system for vehicle steering wheel shimmy, so as to solve the problem of testing and evaluating the unbalanced mass of wheel rim caused by steering wheel shimmy.

[0006] According to one aspect of the present invention, there is provided a system for testing the unbalanced mass tolerance value for vehicle steering wheel shimmy, comprising: a controller, a steering wheel acceleration sensor connected to the controller;

[0007] A steering wheel acceleration sensor, used to test the steering wheel acceleration of each mass block in a test cycle when different mass blocks of different values ​​are attached to a specified position of a front wheel of the vehicle, and transmit the steering wheel acceleration to the controller, wherein the test cycle includes from vehicle startup to a specified driving speed;

[0008] The controller is used to obtain the maximum steering wheel circumferential vibration acceleration for each mass block during the test cycle according to the steering wheel acceleration, and obtain the minimum numerical mass block corresponding to the maximum steering wheel circumferential vibration acceleration greater than or equal to a preset threshold, and use the minimum numerical mass block as the unbalanced mass tolerance value corresponding to the vehicle steering wheel shimmy.

[0009] According to another aspect of the present invention, a method for testing the unbalanced mass tolerance value for vehicle steering wheel shimmy is provided, comprising:

[0010] When attaching mass blocks of different values ​​at a designated position of a front wheel of a vehicle through a steering wheel acceleration sensor, the steering wheel acceleration of each mass block in a test cycle is tested respectively, and the steering wheel acceleration is transmitted to a controller, wherein the test cycle includes from vehicle startup to a designated driving speed;

[0011] The controller obtains the maximum steering wheel circumferential vibration acceleration for each mass block during the test cycle according to the steering wheel acceleration, and obtains the minimum numerical mass block corresponding to the maximum steering wheel circumferential vibration acceleration greater than or equal to the preset threshold, and uses the minimum numerical mass block as the unbalanced mass tolerance value corresponding to the vehicle steering wheel shimmy.

[0012] The technical solution of the embodiment of the present invention can measure the tolerance value of the steering wheel vibration to the unbalanced mass of the wheel side by centrally sticking mass blocks at the specified positions of the wheels, which serves as a robustness evaluation index of the vehicle steering wheel vibration and provides a basis for subsequent vehicle steering wheel vibration optimization design and evaluation work.

[0013] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 is a structural schematic diagram of an unbalanced mass tolerance value testing system for vehicle steering wheel shimmy provided according to Embodiment 1 of the present invention;

[0016] Figure 2 is a schematic diagram of the arrangement of a steering wheel acceleration sensor provided according to the first embodiment of the present invention;

[0017] Figure 3 is a schematic structural diagram of another unbalanced mass tolerance value testing system for vehicle steering wheel shimmy provided according to the second embodiment of the present invention;

[0018] Figure 4 is a flow chart of a method for testing the unbalanced mass tolerance value for vehicle steering wheel shimmy provided in accordance with Embodiment 3 of the present invention;

[0019] Figure 5It is a flow chart of a method for testing the unbalanced mass tolerance value for vehicle steering wheel shimmy provided according to a fourth embodiment of the present invention. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0021] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0022] Embodiment 1

[0023] Figure 1 This is a structural schematic diagram of a system for testing the unbalanced mass tolerance value of vehicle steering wheel shimmy provided in Embodiment 1 of the present invention. The system comprises: a controller 110 and a steering wheel acceleration sensor 120 connected to the controller.

[0024] Among them, the steering wheel acceleration sensor 120 is used to test the steering wheel acceleration of each mass block in a test cycle when different numerical mass blocks are pasted at a specified position of a front wheel of the vehicle, and transmit the steering wheel acceleration to the controller 110, wherein the test cycle includes from vehicle startup to a specified driving speed; the controller 110 is used to obtain the maximum steering wheel circumferential vibration acceleration for each mass block in the test cycle according to the steering wheel acceleration, and obtain the minimum numerical mass block corresponding to the maximum steering wheel circumferential vibration acceleration greater than or equal to a preset threshold, and use the minimum numerical mass block as the unbalanced mass tolerance value corresponding to the vehicle steering wheel shimmy.

[0025] Specifically, a steering wheel acceleration sensor is an electronic device that can measure acceleration force, which can be divided into piezoelectric acceleration sensors, piezoresistive acceleration sensors, capacitive acceleration sensors and servo acceleration sensors. The specific type of the steering wheel acceleration sensor is not limited in this embodiment. As long as it is a sensor that can measure the acceleration of the steering wheel, it is within the scope of protection of this application. The designated position of the wheel may be the rim of the left front or right front wheel of the vehicle, where the rim refers to the outermost circle of the metal part of the vehicle wheel. The mass block may be specifically pasted on the rim of the left front wheel or the rim of the right front wheel. In this embodiment, the position where the mass block is pasted is not limited. The mass block may be pasted on other rotating parts of the wheel side, or may be pasted on the inner surfaces of the left front and right front wheel rims at the same time, all of which are within the protection scope of the present application. A mass block with different numerical values ​​refers to using the numerical value of the mass block as a variable, and simulating the imbalance of the wheel side by changing the numerical value of the mass block. For example, the weight of the mass block is increased in units of 10g starting from 0g, and the corresponding acceleration of the steering wheel under different weights is tested. The designated driving speed may be the maximum driving speed of the vehicle. The testing process of a mass block is a test condition, and a test condition is a process of gradually accelerating the vehicle from starting to the maximum driving speed, which is repeated three times. The test cycle corresponding to each test is specifically a process of gradually accelerating the vehicle from starting to the maximum driving speed. The purpose of testing three times is to take the average value of multiple measurements to ensure the accuracy of the test results.

[0026] Exemplarily, the weight of the mass block is increased in units of 10g starting from 0g. Taking the case where the weight of the mass block is 10g as an example, the mass block is centrally pasted on the inner surface of the left front wheel rim of the vehicle. The steering wheel acceleration sensor 120 measures the steering wheel acceleration corresponding to the mass block with a weight of 10g three times in the process of gradually accelerating from the start of the vehicle to the maximum driving speed, and then takes the average of the three measurement results as the steering wheel acceleration and transmits it to the controller 110. The controller 110 calculates the maximum steering wheel circumferential vibration acceleration corresponding to the 10g mass block according to the received steering wheel acceleration. When it is less than the preset threshold, it means that the steering wheel has not yet shimmied. At this time, the user can continue to increase the mass block in units of 10g to measure again. The above test process is repeated after each increase in the weight of the mass block, and the minimum numerical mass block corresponding to the maximum steering wheel circumferential vibration acceleration is greater than or equal to the preset threshold; wherein the preset threshold is artificially set according to the maximum steering wheel shimmy acceleration allowed when the vehicle is shimmied. If the steering wheel acceleration sensor 120 detects that the steering wheel circumferential acceleration is greater than or equal to the preset acceleration threshold, it can be determined that the steering wheel is in a shimmy state; if the steering wheel acceleration sensor 120 detects that the steering wheel circumferential acceleration is less than the preset acceleration threshold, it can be determined that the steering wheel is not in a shimmy state; when the minimum numerical mass block corresponding to the maximum steering wheel circumferential vibration acceleration is greater than or equal to the preset threshold, the minimum numerical mass block can be used as the unbalanced mass tolerance value corresponding to the vehicle steering wheel shimmy.

[0027] Preferably, the system further includes a vehicle speed sensor 130 connected to the controller 110 ; the sensor is used to obtain the vehicle target driving speed corresponding to the maximum steering wheel circumferential vibration acceleration, and transmit the vehicle target driving speed to the controller 110 .

[0028] Specifically, the vehicle speed sensor 130 is obtained by directly or indirectly detecting the vehicle speed; the vehicle speed sensor 130 can be set on the vehicle body and connected to the controller. The type and installation position of the vehicle speed sensor 130 are not limited in this embodiment; under a test condition, the steering wheel acceleration of the vehicle is constantly changing during acceleration, and the corresponding steering wheel circumferential vibration acceleration obtained according to the steering wheel acceleration is also constantly changing. In this embodiment, the maximum steering wheel circumferential vibration acceleration under each condition is specifically screened out. Since the controller obtains the vehicle speed sent by the vehicle speed sensor in real time, the vehicle speed corresponding to the maximum steering wheel circumferential vibration acceleration under each condition can be determined.

[0029] Preferably, the steering wheel acceleration sensor 120 includes a first steering wheel acceleration sensor 121 located at a first position of the steering wheel, and a second steering wheel acceleration sensor 122 located at a second position of the steering wheel, wherein the first steering wheel acceleration sensor 121 and the second steering wheel acceleration sensor 122 are arranged on the steering wheel rim and are arranged at 90° with the steering wheel rotation axis as the center in the steering wheel plane.

[0030] Figure 2 : is a schematic diagram of the arrangement of steering wheel acceleration sensors, wherein position a is the 12 o'clock position of the steering wheel rim, that is, position a is taken as the first position, and the first steering wheel acceleration sensor 121 is arranged at position a; position b is the 3 o'clock position of the steering wheel rim, that is, position b is taken as the second position, and the second steering wheel acceleration sensor 122 is arranged at position b, and position a and position b are 90° centered on the steering wheel rotation axis in the steering wheel plane, that is, the two steering wheel acceleration sensors are perpendicular to each other. In this embodiment, only the arrangement of the steering wheel acceleration sensors at the 12 o'clock and 3 o'clock positions of the steering wheel is taken as an example, and other steering wheel acceleration sensor position arrangements may also be adopted, such as the 12 o'clock and 9 o'clock positions, the 6 o'clock and 3 o'clock positions, and the 6 o'clock and 9 o'clock positions. In this embodiment, the first position where the first steering wheel acceleration is located and the second position where the second steering wheel are located are not specifically limited, as long as the first steering wheel acceleration sensor 121 and the second steering wheel acceleration sensor 122 are perpendicular to each other, they are all within the protection scope of the present application.

[0031] Preferably, the first steering wheel acceleration sensor 121 is used to test the first steering wheel acceleration for each mass block at the first position of the steering wheel, and transmit the first steering wheel acceleration to the controller; the second steering wheel acceleration sensor 122 is used to test the second steering wheel acceleration for each mass block at the second position of the steering wheel, and transmit the second steering wheel acceleration to the controller.

[0032] Specifically, the first steering wheel acceleration sensor 121 and the second steering wheel acceleration sensor 122 are both connected to the controller 110, and both transmit the steering wheel accelerations corresponding to the pasting of mass blocks of different values ​​to the controller 110, which are respectively recorded as the first steering wheel acceleration and the second steering wheel acceleration; for example, taking the weight of the mass blocks pasted on the inner surface of the left front wheel rim of the vehicle as 10g, the first steering wheel acceleration sensor 121 located at the steering wheel position a will measure the first steering wheel acceleration A corresponding to the pasting of the 10g mass block and transmit it to the controller 110, and the second steering wheel acceleration sensor 122 located at the steering wheel position b will measure the second steering wheel acceleration B corresponding to the pasting of the 10g mass block and transmit it to the controller 110.

[0033] Preferably, the controller 110 is used to obtain the maximum steering wheel circumferential vibration acceleration for each mass block within the test cycle according to the first steering wheel acceleration and the second steering wheel acceleration.

[0034] Specifically, the controller 110 calculates the maximum steering wheel circumferential vibration acceleration of each mass block according to the first steering wheel acceleration and the second steering wheel acceleration in order to cross-validate the calculated steering wheel circumferential vibration acceleration. Figure 2 As shown in the figure, the component of acceleration A along the tangent of the steering wheel is Ay, the component pointing to the center of the steering wheel at the tangent point a is Ax, the component of acceleration B along the tangent of the steering wheel is Bx, and the component pointing to the opposite direction of the center of the steering wheel at the tangent point b is By. Taking the position a where the first steering wheel acceleration sensor is located as an example, the component Ay along the tangent of the steering wheel at the position a includes not only the vibration acceleration in the circumferential direction of the steering wheel, but also the translational acceleration in the plane of the steering wheel. It is impossible to distinguish whether the signal is the circumferential vibration acceleration or the translational acceleration of the steering wheel, and it is easy to misjudge a part of the translational acceleration as the circumferential vibration acceleration; for example, when the steering wheel generates circumferential vibration (i.e. shimmy) and translational vibration along the side of the vehicle at the same time, the component Ay along the tangent of the steering wheel at the position a will superimpose the two components of circumferential vibration and translational vibration. If this signal is directly collected, the translational vibration acceleration will be superimposed, resulting in misjudgment of shimmy. However, the component By pointing in the opposite direction of the steering wheel center at position b only contains translational acceleration. Therefore, subtracting By from Ay can eliminate the translational vibration of the steering wheel along the lateral direction of the vehicle, and only retain the circumferential vibration acceleration of the steering wheel. Similarly, the component Bx along the tangent of the steering wheel at position b minus the component Ax pointing in the direction of the steering wheel center at position a can also eliminate the translational vibration of the steering wheel along the longitudinal direction of the steering wheel plane, and only retain the circumferential vibration acceleration of the steering wheel. Then, the circumferential vibration acceleration of the steering wheel can be accurately obtained by taking the average of the two. Cross-validation can eliminate the superposition of the steering wheel translational acceleration on the circumferential vibration acceleration, and avoid the steering wheel plane Vibrations in other directions such as lateral and longitudinal directions are mistakenly judged as circumferential vibrations; the component Ay along the tangent of the steering wheel at position a minus the component By pointing in the opposite direction of the steering wheel center at position b is recorded as y, that is, y=Ay-By, the component Bx along the tangent of the steering wheel at position b minus the component Ax pointing in the direction of the steering wheel center at position a is recorded as x, that is, x=Bx-Ax, and the average value M of y and x is taken as the steering wheel circumferential vibration acceleration, that is, M=(y+x) / 2; the maximum steering wheel circumferential vibration acceleration can also be obtained by other methods, such as measuring with a steering wheel circumferential vibration angular acceleration sensor.

[0035] The technical solution of the embodiment of the present invention can measure the tolerance value of the steering wheel shimmy to the unbalanced mass of the wheel edge by concentrating the mass blocks on the designated positions of the wheels, which can be used as an evaluation index for the robustness of the steering wheel shimmy of normal vehicles and provide a basis for the subsequent optimization design and evaluation of the steering wheel shimmy of vehicles.

[0036] Embodiment 2

[0037] Figure 3 This is a schematic diagram of the structure of a system for testing the unbalanced mass tolerance value of vehicle steering wheel shimmy provided in the second embodiment of the present invention. This embodiment adds a display device 140 and a storage device 150 on the basis of the above-mentioned first embodiment.

[0038] Preferably, the system also includes a display device 140 connected to the controller 110; the controller 110 is used to transmit the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value to the display device 140; the display device 140 is used to display the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value.

[0039] Specifically, the controller 110 and the display device 140 are connected via a bus. When the controller 110 obtains the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value, they are transmitted to the display device 140. The display device 140 may be a liquid crystal display screen, which is convenient for the user to timely understand the relevant parameter information when the vehicle steering wheel shimmies. The user refers to the technician or relevant staff who designs the vehicle. By understanding the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value, the user can use them as evaluation indicators for evaluating the tolerance of the steering wheel shimmy to the wheel side unbalanced mass vibration excitation and the design robustness, thereby providing a basis for the steering wheel shimmy optimization design and evaluation work. For example, when the unbalance tolerance value is 50g, shimmy occurs. At this time, the user can view through the display device 140 that the maximum steering wheel circumferential vibration acceleration is 3m / s 2 , the corresponding vehicle speed is 30m / s.

[0040] Preferably, the system also includes a storage device 150 connected to the controller; the controller 110 is used to transmit the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value to the storage device 150; the storage device 150 is used to store the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value.

[0041] Specifically, the controller 110 and the storage device 150 are connected via a bus. The storage device 150 refers to a device for storing information, which may be a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. When the controller 110 obtains the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value, they are transmitted to the storage device 150 for storage as historical information.

[0042] Furthermore, the purpose of storage is to facilitate the user to read it when needed later; for example, the user can input a read data instruction through the display device 140, and the data instruction includes the specified data content and the specified time range that the user wants to read, wherein the specified data content can be one or more of the steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value selected by the user for reading, and the specified time range can be set by the user according to the needs, and the input method can be input by touching the virtual button on the display device 140. When the user touches the virtual button for reading data to input the read data instruction, the display device 140 will display the read data. According to the instruction sent to the controller, the controller 110 will execute the reading of the corresponding data content and time range information in the storage device 150 after receiving the read data instruction, and then feed back the corresponding data content and time range information to the display device 140 for display to the user; for example, the user wants to view the unbalanced quality tolerance value measured in May 2022. After inputting the read data instruction through the display device 140, the controller 110 will receive the read data instruction and read the historical information of the unbalanced quality tolerance value measured in May 2022 in the storage device 150, and feed it back to the display device 140 for display to the user, and the user can view it through the display device 140 at this time.

[0043] The technical solution of the embodiment of the present invention can measure the tolerance value of the steering wheel vibration to the unbalanced mass of the wheel side by centrally sticking mass blocks at designated positions of the wheels, and display the obtained value to the user through a display device, and store it through a storage device at the same time, as a robustness evaluation index of the vehicle steering wheel vibration, providing a basis for subsequent vehicle steering wheel vibration optimization design and evaluation work.

[0044] Embodiment 3

[0045] Figure 4 A flow chart of a method for testing the unbalanced mass tolerance value of vehicle steering wheel shimmy provided in the third embodiment of the present invention. The method of the embodiment of the present disclosure specifically includes:

[0046] S110, when attaching mass blocks of different values ​​to a designated position of a front wheel of a vehicle through a steering wheel acceleration sensor, respectively test the steering wheel acceleration of each mass block in a test cycle, and transmit the steering wheel acceleration to a controller.

[0047] Specifically, the weight of the mass block is increased in units of 10g starting from 0g, and the corresponding acceleration of the steering wheel under different weights is tested. Taking the mass block with a weight of 10g as an example, it is centrally pasted on the inner surface of the left front wheel rim of the vehicle. The steering wheel acceleration sensor 120 measures the steering wheel acceleration corresponding to the mass block with a weight of 10g three times respectively. The test cycle corresponding to each test is specifically the process of gradually accelerating from the start of the vehicle to the maximum driving speed. The purpose of testing three times is to take an average of multiple measurements to ensure the accuracy of the test results, and then the average of the three measurement results is taken as the steering wheel acceleration and transmitted to the controller 110.

[0048] Furthermore, two steering wheel acceleration sensors are provided, which are respectively provided at positions a and b of the steering wheel, and positions a and b are arranged at 90° in the plane of the steering wheel with the steering wheel rotation axis as the center, namely the first steering wheel acceleration sensor and the second steering wheel acceleration sensor. Taking the case where the weight of the mass block centrally pasted on the inner surface of the left front wheel rim of the vehicle is 10g as an example, the first steering wheel acceleration sensor located at steering wheel position a will measure the first steering wheel acceleration A corresponding to the pasted 10g mass block and transmit it to the controller, and the second steering wheel acceleration sensor located at steering wheel position b will measure the second steering wheel acceleration B corresponding to the pasted 10g mass block and transmit it to the controller.

[0049] S120. Obtain, through the controller, the maximum steering wheel circumferential vibration acceleration for each mass block during the test cycle according to the steering wheel acceleration, and obtain the minimum numerical mass block corresponding to the maximum steering wheel circumferential vibration acceleration being greater than or equal to a preset threshold, and use the minimum numerical mass block as the unbalanced mass tolerance value corresponding to the vehicle steering wheel shimmy.

[0050] Specifically, the maximum steering wheel circumferential vibration acceleration of each mass block can be obtained through the cross-validation method. The controller calculates the maximum steering wheel circumferential vibration acceleration of each mass block according to the first steering wheel acceleration and the second steering wheel acceleration. For example, the controller calculates the maximum steering wheel circumferential vibration acceleration corresponding to the 10g mass block. When it is less than the preset threshold, it means that the steering wheel has not yet experienced shimmy. At this time, the user can continue to increase the mass block in units of 10g and measure again. After each increase in the weight of the mass block, the above test process is repeated to obtain the minimum numerical mass block whose maximum steering wheel circumferential vibration acceleration is greater than or equal to the preset threshold; the preset threshold is set artificially according to the maximum steering wheel shimmy acceleration allowed when the vehicle is subjected to a shimmy test.

[0051] For example, the preset threshold is set to 3 m / s based on the maximum steering wheel shimmy acceleration allowed during the shimmy test of the vehicle. 2 , the maximum steering wheel vibration acceleration corresponding to the 10g mass block is 2m / s 2 If the value is smaller than the preset threshold, it means that no steering wheel shimmy occurs when the 10g mass block is attached. The maximum steering wheel shimmy acceleration corresponding to the 50g mass block is 4m / s. 2 If it is greater than the preset threshold, it means that the steering wheel shimmy occurs when the 50g mass block is attached. When the corresponding maximum steering wheel shimmy acceleration when the 50g mass block and the 60g mass block are attached are both greater than the preset threshold, the minimum value mass block, that is, 50g, is used as the unbalanced mass tolerance value corresponding to the vehicle steering wheel shimmy.

[0052] The technical solution of the embodiment of the present invention can measure the tolerance value of the steering wheel vibration to the unbalanced mass of the wheel side by centrally sticking mass blocks at the specified positions of the wheels, which serves as a robustness evaluation index of the vehicle steering wheel vibration and provides a basis for subsequent vehicle steering wheel vibration optimization design and evaluation work.

[0053] Embodiment 4

[0054] Figure 5 A flow chart of a method for testing the unbalanced mass tolerance value of a vehicle steering wheel shimmy provided in the fourth embodiment of the present invention. This embodiment adds a method flow for a display device based on the above third embodiment, such as Figure 5 As shown, the specific contents of step S210 to step S220 are substantially the same as those of step S110 to step S120 in implementation 3, and therefore will not be described in detail in this implementation. The method of the embodiment of the present disclosure specifically includes:

[0055] S210, when attaching mass blocks of different values ​​to a designated position of a front wheel of the vehicle through a steering wheel acceleration sensor, respectively test the steering wheel acceleration of each mass block in a test cycle, and transmit the steering wheel acceleration to the controller.

[0056] S220. Obtain, through the controller, the maximum steering wheel circumferential vibration acceleration for each mass block during the test cycle according to the steering wheel acceleration, and obtain the minimum numerical mass block corresponding to the maximum steering wheel circumferential vibration acceleration being greater than or equal to a preset threshold, and use the minimum numerical mass block as the unbalanced mass tolerance value corresponding to the vehicle steering wheel shimmy.

[0057] S230: transmitting the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value to the display device through the controller.

[0058] Specifically, when the controller obtains the maximum steering wheel circumferential vibration acceleration, the vehicle's target driving speed and the unbalanced mass tolerance value, it transmits them to the display device, so that the user can timely understand the maximum steering wheel circumferential vibration acceleration, the vehicle's target driving speed and the unbalanced mass tolerance value when the vehicle's steering wheel vibrates.

[0059] S240. Display the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value through a display device.

[0060] Specifically, the display device can be a liquid crystal display screen, which will display the maximum steering wheel circumferential vibration acceleration, the vehicle's target driving speed and the unbalanced mass tolerance value transmitted by the controller. For example, the user can understand the relevant parameter information when the vehicle steering wheel vibrates on the LCD screen, and it can be used as an evaluation indicator for evaluating the tolerance of the steering wheel vibration to the wheel-side unbalanced mass vibration excitation and the design robustness, thereby providing a basis for the steering wheel vibration optimization design and evaluation work.

[0061] Preferably, the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value are transmitted to the storage device through the controller; and the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value are stored through the storage device.

[0062] Specifically, when the controller obtains the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value, it transmits them to the storage device, which can be a portable computer disk, hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination of the above; when the controller obtains the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value, it transmits them to the storage device for storage as historical information; so that the user can read it when needed later.

[0063] The technical solution of the embodiment of the present invention can measure the tolerance value of the steering wheel vibration to the unbalanced mass of the wheel side by centrally sticking mass blocks at the specified positions of the wheels, which serves as a robustness evaluation index of the vehicle steering wheel vibration and provides a basis for subsequent vehicle steering wheel vibration optimization design and evaluation work.

[0064] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0065] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A system for testing the unbalanced mass tolerance value of vehicle steering wheel shimmy, characterized in that: include: A controller, a steering wheel acceleration sensor connected to the controller, wherein the steering wheel acceleration sensor comprises a first steering wheel acceleration sensor located at a first position of the steering wheel, and a second steering wheel acceleration sensor located at a second position of the steering wheel, wherein the first steering wheel acceleration sensor and the second steering wheel acceleration sensor are arranged on a steering wheel rim and arranged at 90° with the steering wheel rotation axis as the center in a steering wheel plane; The steering wheel acceleration sensor is used to test the steering wheel acceleration of each mass block in a test cycle when different mass blocks with different values ​​are attached to a specified position of a front wheel of the vehicle, and transmit the steering wheel acceleration to the controller, wherein the test cycle includes from vehicle startup to a specified driving speed; The controller is used to obtain the maximum steering wheel circumferential vibration acceleration for each mass block in the test cycle according to the steering wheel acceleration, and obtain the minimum value mass block corresponding to the maximum steering wheel circumferential vibration acceleration being greater than or equal to a preset threshold, and use the minimum value mass block as the unbalanced mass tolerance value corresponding to the vehicle steering wheel shimmy; The controller is used to obtain a maximum steering wheel circumferential vibration acceleration for each mass block in the test cycle according to the first steering wheel acceleration and the second steering wheel acceleration; Among them, the calculation process of the steering wheel circumferential vibration acceleration is: record the component Ay along the steering wheel tangent at the first position minus the component By pointing in the opposite direction of the steering wheel center at the second position as y, record the component Bx along the steering wheel tangent at the second position of the steering wheel minus the component Ax pointing in the direction of the steering wheel center at the first position as x, and take the average value M of y and x as the steering wheel circumferential vibration acceleration.

2. The system according to claim 1, characterized in that The system also includes a vehicle speed sensor connected to the controller; The vehicle speed sensor is used to obtain the vehicle target driving speed corresponding to the maximum steering wheel circumferential vibration acceleration, and transmit the vehicle target driving speed to the controller.

3. The system according to claim 1, characterized in that The first steering wheel acceleration sensor is used to test a first steering wheel acceleration for each mass block at a first steering wheel position, and transmit the first steering wheel acceleration to the controller; The second steering wheel acceleration sensor is used to test a second steering wheel acceleration for each mass block at a second steering wheel position, and transmit the second steering wheel acceleration to the controller.

4. The system according to claim 2, characterized in that The system also includes a display device connected to the controller; The controller is used to transmit the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value to the display device; The display device is used to display the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value.

5. The system according to claim 2, characterized in that The system also includes a storage device connected to the controller; The controller is used to transmit the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value to the storage device; The storage device is used to store the maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value.

6. A method for testing the unbalanced mass tolerance value of vehicle steering wheel shimmy, applied to the system according to any one of claims 1 to 5, characterized in that: include: When attaching mass blocks of different values ​​at a designated position of a front wheel of a vehicle through a steering wheel acceleration sensor, respectively testing the steering wheel acceleration of each mass block in a test cycle, and transmitting the steering wheel acceleration to the controller, wherein the test cycle includes from vehicle startup to a designated driving speed; The controller obtains the maximum steering wheel circumferential vibration acceleration for each mass block during the test cycle according to the steering wheel acceleration, and obtains the minimum numerical mass block corresponding to the maximum steering wheel circumferential vibration acceleration greater than or equal to a preset threshold, and uses the minimum numerical mass block as the unbalanced mass tolerance value corresponding to the vehicle steering wheel shimmy.

7. The method according to claim 6, characterized in that The controller obtains the maximum steering wheel circumferential vibration acceleration for each mass block in the test cycle according to the steering wheel acceleration, obtains the minimum value mass block corresponding to the maximum steering wheel circumferential vibration acceleration being greater than or equal to a preset threshold, and uses the minimum value mass block as the unbalanced mass tolerance value, further comprising: The maximum steering wheel circumferential vibration acceleration, the target vehicle speed and the unbalanced mass tolerance value are transmitted to a display device through a controller; The maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value are displayed by the display device.

8. The method according to claim 6, characterized in that The controller obtains the maximum steering wheel circumferential vibration acceleration for each mass block in the test cycle according to the steering wheel acceleration, obtains the minimum value mass block corresponding to the maximum steering wheel circumferential vibration acceleration being greater than or equal to a preset threshold, and uses the minimum value mass block as the unbalanced mass tolerance value, further comprising: The maximum steering wheel circumferential vibration acceleration, the target vehicle speed and the unbalanced mass tolerance value are transmitted to a storage device through a controller; The maximum steering wheel circumferential vibration acceleration, the vehicle target driving speed and the unbalanced mass tolerance value are stored by the storage device.

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