A method for testing mechanical properties of commercial vehicle tires based on whole vehicle testing

Abstract

The present application relates to the technical field of tire characteristic test, and particularly relates to a commercial vehicle tire mechanical characteristic test method based on whole vehicle test, comprising: obtaining a plurality of tires which pass bench test and a measuring instrument are installed on a test whole vehicle; performing a plurality of preset operations on the test whole vehicle to obtain first operation data and first round test data; comparing the first operation data and the first round test data, calibrating the first operation data to obtain second operation data; performing pre-test on the whole vehicle to be tested to obtain test working condition parameters; performing mechanical characteristic test according to the test working condition parameters and the second operation data to obtain corresponding second round test data; and obtaining mechanical characteristic parameters of the tire according to the second operation data and the second round test data. The present application adjusts the load of the whole vehicle to adjust the tire stress in the whole vehicle test, meets the loading capacity required in the mechanical characteristic test of the commercial vehicle tire, and does not need to perform bench test.

Description

Technical Field

[0001] The present invention relates to the technical field of tire property testing, and in particular to a commercial vehicle tire mechanical property testing method based on whole vehicle testing. Background Art

[0002] As the sole contact component between a vehicle and the ground, tire performance has a crucial impact on a vehicle's driving performance, safety, comfort, and fuel economy. In the commercial vehicle sector, particularly, high-performance tires are crucial to overall vehicle performance. Therefore, obtaining a comprehensive set of tire mechanical property data to construct tire models is crucial for tire research and development. Current tire mechanical property test benches generally have a maximum load capacity below 30 kN, which can only cover the mechanical property testing of passenger car and a small number of light truck tires, and cannot be used for mechanical property testing of commercial vehicle tires.

[0003] For example, Chinese patent application publication number: CN102435449A discloses a composite four-bar tire mechanical property testing machine, including an arc guide rail device composed of a base hydraulic cylinder and an arc guide rail, a composite four-bar linkage assembly composed of a base, four connecting rods, a large rocker mechanism, and a small rocker mechanism, a vertical loading slide plate assembly composed of a box, a guide rail, a slide plate, a hydraulic cylinder, a hydraulic cylinder connecting platform, and an upper transition platform, a six-component force sensor and a drive brake device assembly composed of a six-component force sensor and a drive brake device.

[0004] The tire mechanical properties testing machine in the above technical solution has a complex structure, and the vertical loading part cannot simulate the load required by large commercial vehicles, and cannot be used for mechanical properties testing of commercial vehicle tires. Summary of the Invention

[0005] To this end, the present invention provides a commercial vehicle tire mechanical property testing method based on whole vehicle testing, so as to overcome the problem in the prior art that the maximum loading capacity of indoor bench tests is insufficient and cannot be used for mechanical property testing of commercial vehicle tires.

[0006] To achieve the above objectives, the present invention provides a commercial vehicle tire mechanical property testing method based on whole vehicle testing, comprising:

[0007] Obtain several tires that have passed the bench test and configure them on the test vehicle;

[0008] The configured vehicle is equipped with measuring instruments, including six-component wheel force sensors, on-board K&C test equipment, dual-axis velocity sensors, gyroscopes, torque steering wheels, and altimeters, to obtain test data for the vehicle and tires while driving.

[0009] Performing a number of preset operations on the vehicle to be tested, and obtaining corresponding first operation data and first round test data according to the preset operations;

[0010] wherein, based on the first operating data and the first round of test data, the test stability of the entire vehicle is determined, and the first operating data is calibrated according to the result of the test stability to obtain the second operating data;

[0011] For the tire to be tested, place the tire on a test vehicle that has passed the stability assessment.

[0012] Conducting a pre-test on a vehicle equipped with the tire to be tested to determine test operating condition parameters, wherein the test operating condition parameters include braking operating condition parameters;

[0013] performing a plurality of mechanical property tests on a test vehicle equipped with the tire to be tested based on the test operating condition parameters and the second operating data to obtain corresponding second round of test data;

[0014] The mechanical characteristic parameters of the tire to be tested are determined based on the second operation data and the second round of test data.

[0015] Furthermore, the several mechanical property tests include:

[0016] Cornering characteristic test, longitudinal sliding characteristic test, cornering and longitudinal sliding combined characteristic test, lateral relaxation length test and effective rolling radius test.

[0017] Furthermore, the plurality of preset operations include a vehicle uniform speed driving performance test and a vehicle turning performance test.

[0018] Furthermore, calibrating the first operation data to obtain second operation data according to the result of the stability test includes:

[0019] Screening the available first operation data and first round test data, and excluding out-of-field data;

[0020] comparing the first operation data with the first round of test data;

[0021] Determine the maximum deviation between the first operation data and the first round of test data according to the comparison calculation;

[0022] The test stability of the entire vehicle is determined based on the maximum deviation value.

[0023] Furthermore, judging the test stability of the entire vehicle based on the maximum deviation value includes:

[0024] If the maximum deviation value is less than or equal to the set threshold, the vehicle is judged to have passed the test stability test;

[0025] If the maximum deviation value is greater than a set threshold, it is determined that the test stability of the entire vehicle is unqualified, and the preset operation is repeated to obtain several maximum deviation values, and the several maximum deviation values ​​are processed to obtain regression values.

[0026] Furthermore, after obtaining the regression value, the method further includes:

[0027] calibrating the first operating data based on the regression value to obtain the second operating data;

[0028] Furthermore, the pre-test includes:

[0029] Perform pre-positioning operation on the test vehicle to obtain the pre-positioning speed and target test speed;

[0030] The tire slip rate is calculated by using the six-component wheel force and the gyroscope to obtain the tire speed and the actual instantaneous speed of the vehicle under uniform speed and braking conditions;

[0031] Compare the front speed and the initial target test speed when the tire slip rate is 0 to determine whether it meets the requirements.

[0032] If it does not meet the requirements, repeat the preceding operations until it meets the requirements;

[0033] The target test speed when the requirements are met is recorded as the braking condition parameter.

[0034] Furthermore, the tire cornering characteristic detection includes:

[0035] Based on the second operational data, the test vehicle is driven in a straight line at a constant speed for a period of time. The steering wheel is then turned left at a constant speed to a maximum lateral acceleration. The maximum steering wheel angle is maintained for a period of time, and then the steering wheel is returned to the initial position at the same speed. This is repeated multiple times. The measuring instrument measures the change in wheel posture and the forces and moments acting on the tires.

[0036] Based on the second operation data, the test vehicle is driven in a straight line at a constant speed for a period of time, and then the steering wheel is turned right at a constant speed to a maximum lateral acceleration. The maximum steering wheel angle is maintained for a period of time, and then the steering wheel is returned to the initial position at the same speed, and this is repeated multiple times; a measuring instrument is used to measure the change in wheel posture and the force and torque applied to the tire;

[0037] The tire longitudinal slip characteristics test includes:

[0038] According to the second operating data and the braking condition parameters, the vehicle is accelerated to a certain speed, then shifted into neutral, and then coasted to a certain speed, then braked with a certain braking force until the wheel to be tested is completely locked, and this is repeated multiple times;

[0039] The measuring instrument measures the wheel posture change and the force and torque applied to the tire.

[0040] The tire side slip composite characteristic test includes:

[0041] Based on the second operating data and the braking condition parameters, the vehicle is driven at a constant speed around a circle of a certain radius, and braking is performed with a certain braking force until the wheel to be tested is completely locked, and the test is repeated multiple times. The same test is performed in the opposite direction and repeated multiple times.

[0042] Measuring the wheel posture change and the forces and moments acting on the tire using the measuring instrument;

[0043] Furthermore, the tire lateral relaxation length test includes:

[0044] According to the second operation data, after the vehicle has been driving in a straight line at a constant speed for a period of time, a steering wheel frequency sweep test is performed at a certain frequency. The vehicle load is changed and the same frequency sweep test is performed multiple times.

[0045] Measuring the wheel posture change and the forces and moments acting on the tire using the measuring instrument;

[0046] The lateral slack length of the tire is calculated based on the second operation data and the obtained second round test data.

[0047] Furthermore, the tire effective rolling radius test includes:

[0048] Based on the second operation data, the vehicle is driven in a straight line at a plurality of constant speeds, the vehicle load is changed, and the same test is repeated multiple times;

[0049] Measuring the wheel posture change and the forces and moments acting on the tire using the measuring instrument;

[0050] The effective rolling radius of the tire is calculated based on the second operating data and the obtained second round of test data.

[0051] Compared with the prior art, the beneficial effect of the present invention is that the commercial vehicle tire mechanical property testing method based on whole vehicle testing of the present invention can fully utilize existing whole vehicle testing equipment by obtaining mechanical property test data for constructing a tire model based on whole vehicle testing. The additional cost is very low, and the tire force can be easily adjusted by adjusting the load of the test vehicle, covering the loading capacity required for commercial vehicle tire mechanical property testing.

[0052] Furthermore, the present invention corrects the operating parameters during the mechanical property test by performing a number of preset operations on the whole vehicle to be tested, thereby eliminating the test errors caused by the whole vehicle test.

[0053] Furthermore, the present invention determines the test condition parameters required for partial mechanical property testing by conducting a pre-test on the entire vehicle to be tested.

[0054] Furthermore, the present invention obtains comprehensive mechanical property test data required for constructing a tire model while reducing the number of test steps through cornering characteristic tests, longitudinal slip characteristic tests, cornering and longitudinal slip combined characteristic tests, lateral relaxation length tests, and effective rolling radius tests. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 This is a flow chart of a commercial vehicle tire mechanical property testing method based on full vehicle testing of the present invention;

[0056] Figure 2 Schematic diagram of left-side bias characteristic test;

[0057] Figure 3 Schematic diagram of right-side bias characteristic test;

[0058] Figure 4 Schematic diagram of the longitudinal sliding characteristics test. DETAILED DESCRIPTION

[0059] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention.

[0060] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0061] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside", and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0062] Furthermore, it should be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0063] See also Figure 1 As shown, Figure 1This is a flow chart of a commercial vehicle tire mechanical property testing method based on a whole vehicle test. Specifically, an embodiment of the present invention provides a commercial vehicle tire mechanical property testing method based on a whole vehicle test, including:

[0064] Step S1, obtaining a number of tires that have passed the bench test and configuring them on a test vehicle;

[0065] Among them, passing the bench test means that the tire has known stable performance parameters and meets the requirements of safe driving. The safe driving requirements include but are not limited to the tire pressure requirements and dynamic balance requirements of each tire of the vehicle. Those skilled in the art can set them according to the driving requirements of the vehicle, which will not be repeated here.

[0066] Step S2: arranging measuring instruments on the configured vehicle, including a six-component wheel force sensor, an on-board K&C test device, a dual-axis speed sensor, a gyroscope, a torque steering wheel, and an altimeter, to obtain test data of the tires of the vehicle while it is running;

[0067] Among them, the test data of the whole vehicle while driving includes the longitudinal force Fx, lateral force Fy, vertical load Fz, overturning moment Mx, return moment Mz and wheel speed measured by the six-component wheel force sensor, the wheel angle and roll angle measured by the on-board K&C test equipment, the wheel sideslip angle measured by the dual-axis speed sensor, the vehicle's instantaneous speed measured by the gyroscope, and the vehicle body height measured by the altimeter.

[0068] Step S3, performing a number of preset operations on the vehicle to be tested, and obtaining corresponding first operation data and first round test data according to the preset operations;

[0069] wherein, based on the first operating data and the first round of test data, the test stability of the entire vehicle is determined, and the first operating data is calibrated according to the result of the test stability to obtain the second operating data;

[0070] Specifically, the preset operation includes step S31 of uniform speed driving performance test and step S32 of vehicle turning performance test;

[0071] In practice, step S31, the uniform speed driving performance test includes:

[0072] The test vehicle is driven straight at a constant speed of 30 seconds at the speed displayed on the vehicle instrument panel and the first operating data (60 km / h). The gyroscope is used to obtain the true instantaneous speed of the test vehicle every 3 seconds during the above-mentioned constant speed straight driving process. The maximum value of |60-true instantaneous speed| is compared and recorded as the absolute maximum speed deviation value. If It is considered that the uniform speed of the test vehicle is consistent, and the average speed deviation value is 0. On the contrary, if It is considered that the uniform speed driving of the whole vehicle used in the above test does not have single consistency;

[0073] If the uniform speed of the test vehicle is not consistent, repeat step S31 10 times to run the test vehicle in a straight line at a uniform speed of 60 km / h displayed on the vehicle instrument for 30 seconds, and compare the maximum speed deviation value = 60-real instantaneous speed, and then get

[0074] If the average speed deviation value meets the preset deviation range, it is determined that the uniform speed driving of the test vehicle is consistent.

[0075] If the average speed deviation value exceeds the preset deviation range, it is determined that the uniform speed driving of the test vehicle is not consistent, and the performance of the vehicle drive equipment is adjusted until the uniform speed driving of the test vehicle is consistent.

[0076] In practice, the preset deviation range is usually set to 0 to 60*5% km / h.

[0077] In practice, step S32, the vehicle turning performance test includes:

[0078] Determine the steering wheel transmission ratio of the test vehicle, record the transmission ratio as S, drive in a straight line at a constant speed of V1 for 30 seconds, turn the steering wheel 60 degrees to the right at a constant speed, maintain the above steering wheel angle for 1 second, then return the steering wheel to the initial position at the same speed, drive in a straight line at a constant speed for 30 seconds, then turn the steering wheel 60 degrees to the left at a constant speed, maintain the above steering wheel angle for 1 second, then return the steering wheel to the initial position at the same speed, obtain the tire rotation angle when the steering wheel is turned 60 degrees to the left and 60 degrees to the right through the vehicle-mounted K&C test equipment, and compare to obtain the maximum Recorded as the absolute maximum transmission ratio deviation value, if It is considered that the turning performance of the above test vehicle is consistent, and the average angle deviation value is recorded as 0. On the contrary, if It is considered that the turning of the vehicle used in the above test does not have single consistency;

[0079] If the turning of the test vehicle does not have single-time consistency, repeat step S32 10 times: driving in a straight line at a constant speed of V1 for 30 seconds, turning the steering wheel 60 degrees to the right at a constant speed, keeping the steering wheel angle for 1 second, and then returning the steering wheel to the initial position at the same speed; then driving in a straight line at a constant speed for 30 seconds, turning the steering wheel 60 degrees to the left at a constant speed, keeping the steering wheel angle for 1 second, and then returning the steering wheel to the initial position at the same speed. Then we can get,

[0080]

[0081] It can be understood that in the above preset operations, the first operation data includes the speed displayed on the vehicle instrument and the steering wheel rotation angle, and the first round of test data corresponds to the actual instantaneous speed of the whole vehicle and the tire angle tested by the on-board K&C test equipment.

[0082] Specifically, in step S3, the following is also included:

[0083] The calibrating the first operation data according to the result of the stability test to obtain the second operation data comprises:

[0084] Step S301, filter the available first operation data and first round test data, and exclude wild point data; the wild point data is the point where the change gradient of the sampling value (i.e., the first operation data and the first round test data) cannot be reached within a sampling cycle in the actual system, and will not be repeated here.

[0085] Step S302: comparing the first operation data with the first round of test data, and determining a maximum deviation between the first operation data and the first round of test data based on the comparison calculation;

[0086] Step S303: judging the test stability of the entire vehicle based on the maximum deviation value.

[0087] In the implementation, in step S31, the deviation data that meets the preset deviation range is The second operation data is obtained as 60+the average speed deviation value, which is recorded as V1, that is, V1=60+the average speed deviation value.

[0088] In practice, in step S32, the deviation data is , record the steering wheel angle operation data in the subsequent mechanical properties test as R0, and obtain the second operation data = The second operation data is recorded as R1, that is,

[0089] It is understandable that the single data difference is calculated, that is, the maximum speed deviation value 1, the maximum speed deviation value 2, ..., the maximum speed deviation value 10 , which is obtained by subtracting the single first operation data from the first round of test data. That is, the maximum transmission ratio deviation value 1, the maximum transmission ratio deviation value 2, ..., the maximum transmission ratio deviation value 1 0， It is also calculated based on the single first operation data and the first round of test data, and will not be described in detail here.

[0090] Step S4: placing the tire to be tested on a test vehicle that has passed the stability assessment.

[0091] It can be understood that the stability is qualified when the uniform speed driving of the whole vehicle is consistent in the uniform speed driving performance test and the turning performance test of the vehicle is consistent.

[0092] Step S5, performing a pre-test on the vehicle to be tested to obtain test operating condition parameters;

[0093] Specifically, pre-tests include:

[0094] The test vehicle is accelerated to a certain speed (pre-set as the lead speed V0), put into neutral, and coasted to a corresponding speed (the target test speed V2, V0>V2). After that, the vehicle is braked with a braking force of 50N / s. The tire speeds of the test vehicle without braking force and with braking force applied are obtained from the six-component wheel force and the gyroscope during the process from the lead speed V0 to the stop of the test vehicle. According to the tire slip rate formula, the following is obtained:

[0095]

[0096] The target test speed V2 when the tire slip rate is equal to 0 for the first time (that is, the first time when the tire speed when braking force is applied is the same as the tire speed when no braking force is applied) is recorded as the braking condition parameter. If the tire slip rate is not equal to 0, repeat the above test, reduce the target test speed V2 (and increase the neutral time) until the tire slip rate is equal to 0, and record the new target test speed V2. The target test speed V2 is the braking condition parameter.

[0097] Step S6, performing several mechanical property tests on the test vehicle equipped with the tire to be tested based on the test operating condition parameters to obtain corresponding second round test data;

[0098] Among them, the mechanical property tests include: lateral deviation property test, longitudinal slip property test, lateral deviation and longitudinal slip combined property test, lateral relaxation length test and effective rolling radius test.

[0099] It is understandable that the test items of the mechanical properties test are the same as the tire mechanical properties items obtained by the mechanical properties test items tested on the tire mechanical properties test bench, and will not be repeated here.

[0100] Specifically, the cornering characteristics test includes:

[0101] After the test vehicle has been traveling in a straight line at a constant speed of V1 for a period of time, the steering wheel is turned left to R1 at a constant speed of 20° / s. After maintaining the above steering wheel angle for 1 second, the steering wheel is returned to the 0° position (straight-line driving position) at the same speed. Repeat the test three times.

[0102] The input schematic diagram of the left steering wheel working condition test under ideal state (i.e., the transmission ratio S of the test vehicle is 10, the steering wheel angle is 120°, and the vehicle speed is kept unchanged) is shown in Figure 2 As shown in the figure, the second round of test data measured during the test includes the wheel posture changes (the side slip angle, the roll angle, the wheel center speed, and the wheel speed) and the forces and moments (the longitudinal force Fx, the lateral force Fy, the vertical load Fz, the roll moment Mx, and the aligning moment Mz) borne by the tire.

[0103] After the vehicle travels at a constant speed V1 for a period of time, the steering wheel is turned right at a constant speed of 20° / s to R1, and after maintaining the above steering wheel angle for 1s, the steering wheel is turned back to the 0° position (straight driving position) at the same speed, and the test is repeated three times.

[0104] The input schematic diagram of the right steering wheel working condition test under ideal state (i.e., the transmission ratio S of the test vehicle is 10, the steering wheel angle is 120°, and the vehicle speed is kept unchanged) is shown in Figure 3 As shown in the figure, the second round of test data measured during the test includes the wheel posture changes (the side slip angle, the roll angle, the wheel center speed, and the wheel speed) and the forces and moments (the longitudinal force Fx, the lateral force Fy, the vertical load Fz, the roll moment Mx, and the aligning moment Mz) borne by the tire.

[0105] Specifically, the longitudinal slip characteristic test includes:

[0106] The test vehicle is accelerated to the front speed V0, and the brake is applied at a braking force of 50 N / s when the test vehicle is sliding to the target test speed V2, until the test vehicle wheels are completely locked, i.e., the tire slip ratio changes from 0 to -100%, and the test is repeated three times.

[0107] The input schematic diagram of the test under ideal state (i.e., the target speed V2 is 60 km / s, and the test vehicle wheels can be completely locked after braking) is shown in Figure 4 As shown in the figure, the second round of test data measured during the test includes the wheel posture changes (the side slip angle, the roll angle, the wheel center speed, and the wheel speed) and the forces and moments (the longitudinal force Fx, the lateral force Fy, the vertical load Fz, the roll moment Mx, and the aligning moment Mz) borne by the tire.

[0108] Specifically, the side slip and longitudinal slip combined characteristic test includes:

[0109] The test vehicle travels at a constant speed around a circle with a radius of 100 m at the target test speed V2, and the brake is applied at a braking force of 50 N / s until the test vehicle wheels are completely locked, i.e., the tire slip ratio changes from 0 to -100%, and the test is repeated three times. The same test is performed in the opposite direction around a circle with a radius of 100 m, and the test is repeated three times.

[0110] The same test was then repeated on two other circles with radii of 150m and 200m, respectively. The second-wheel test data measured during each test included wheel attitude changes (slip angle, roll angle, wheel center speed, and wheel rotational speed) and the forces and moments acting on the tire (longitudinal force Fx, lateral force Fy, vertical load Fz, overturning moment Mx, and aligning moment Mz).

[0111] Specifically, the lateral relaxed length test involves:

[0112] After the test vehicle traveled in a straight line at a constant speed of V1 for a period of time, a steering wheel frequency sweep test was performed at frequencies of 1Hz, 2Hz, 3Hz, 4Hz, and 5Hz. The vehicle load was increased twice, by 1000kg each time, and the same frequency sweep test was repeated. The second round of test data measured during the test included wheel attitude changes (slip angle, roll angle, wheel center speed, wheel speed) and tire forces and moments (longitudinal force Fx, lateral force Fy, vertical load Fz, overturning moment Mx, and aligning moment Mz).

[0113] Specifically, the effective rolling radius test includes:

[0114] The test vehicle was driven in a straight line at a constant speed at six speeds (V1-40 km / h, V1-20 km / h, V1, V1+20 km / h, V1+40 km / h, and V1+80 km / h). The vehicle load was increased twice, each time by 1000 kg, and the same test was carried out on each of the two tests. The second round of test data measured during the test included wheel attitude changes (slip angle, roll angle, wheel center speed, wheel speed) and the forces and moments acting on the tire (longitudinal force Fx, lateral force Fy, vertical load Fz, overturning moment Mx and righting moment Mz).

[0115] Step S7: obtaining mechanical characteristic parameters of the tire according to the second operation data and the second round of test data.

[0116] Specifically, the tire mechanical characteristic parameters that need to be calculated include lateral relaxation length and effective rolling radius.

[0117] Specifically, the lateral relaxation length is calculated as:

[0118] The slip angle in the second round of test data obtained in the lateral slack length test is expressed as a sine function, where α is the real-time slip angle of the wheel obtained in the second round of test data in the side slip characteristic test, which is a sine function and can be expressed by formula (1):

[0119] α=α0sin(2πf t+ψ1) (1)

[0120] The lateral force Fy obtained in the second round of test data in the lateral slack length test is expressed as a sine function, where F is the lateral force Fy of the tire obtained in the second round of test data in the cornering characteristic test, which is a sine function and can be expressed by formula (2):

[0121] F=F0sin(2πf t+ψ2) (2)

[0122] The lag time of the tire's lateral force (relative to the sideslip angle) is Where, ψ1 is calculated according to formula (1), and ψ2 is calculated according to formula (2). Since the test frequency is the same, πf is the same in formula (1) and formula (2);

[0123] It can be concluded that the lateral slack length of the tire = V1×Δt.

[0124] Specifically, the effective rolling radius is calculated as:

[0125] The wheel speed in the second round of test data obtained in the effective rolling radius test is recorded as Ω, in rad / s, and the vehicle speed is recorded as Vx, in m / s. Then, it can be calculated that the effective rolling radius = Vx / Ω.

[0126] Specifically, the second round of test data obtained in the cornering characteristic test includes the wheel posture change and the force and torque applied to the tire, which is the cornering characteristic test data of the tested tire.

[0127] Specifically, in the longitudinal slip characteristic test, the second round of test data obtained includes the wheel posture change and the force and torque exerted on the tire, which is the longitudinal slip characteristic test data of the test tire.

[0128] Specifically, the second round of test data obtained in the cornering and longitudinal slip combined characteristic test includes the wheel posture change and the force and torque exerted on the tire, which is the cornering and longitudinal slip combined characteristic test data of the test tire.

[0129] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A commercial vehicle tire mechanical properties testing method based on full vehicle testing, characterized in that: include: Obtain several tires that have passed the bench test and place the tires to be tested on the test vehicle; The configured vehicle is equipped with measuring instruments, including six-component wheel force sensors, on-board K&C test equipment, dual-axis velocity sensors, gyroscopes, torque steering wheels, and altimeters, to obtain test data for the vehicle and tires while driving. Performing a plurality of preset operations on the vehicle to be tested, and obtaining corresponding first operation data and first round test data according to the preset operations, wherein the plurality of preset operations include a vehicle uniform speed driving performance test and a vehicle turning performance test; The step of determining the test stability of the vehicle based on the first operating data and the first round of test data, and calibrating the first operating data according to the result of the test stability to obtain second operating data, wherein the step of calibrating the first operating data according to the result of the test stability to obtain second operating data includes: Screening the available first operation data and first round test data, and excluding out-of-field data; comparing the first operation data with the first round of test data; Determine the maximum deviation between the first operation data and the first round of test data according to the comparison calculation; Determining the test stability of the entire vehicle based on the maximum deviation value; if the maximum deviation value is less than or equal to a set threshold, determining that the test stability of the entire vehicle is qualified; if the maximum deviation value is greater than the set threshold, determining that the test stability of the entire vehicle is unqualified; repeating a preset operation to obtain several maximum deviation values; processing the several maximum deviation values ​​to obtain regression values; and calibrating the first operation data based on the regression values ​​to obtain the second operation data; For the tire to be tested, the tire to be tested is configured on a test vehicle that has passed the stability assessment, wherein the stability assessment is passed if the test vehicle has consistent uniform speed driving in the vehicle uniform speed driving performance test and consistent turning driving in the vehicle turning performance test; Conducting a pre-test on a vehicle equipped with the tire to be tested to determine test operating condition parameters, wherein the test operating condition parameters include braking operating condition parameters; performing a plurality of mechanical property tests on a test vehicle equipped with the tire to be tested based on the test operating condition parameters and the second operating data to obtain corresponding second round of test data; The mechanical characteristic parameters of the tire to be tested are determined based on the second operation data and the second round of test data.

2. The commercial vehicle tire mechanical property testing method based on full vehicle testing according to claim 1, characterized in that: The mechanical properties tests include: Cornering characteristic test, longitudinal sliding characteristic test, cornering and longitudinal sliding combined characteristic test, lateral relaxation length test and effective rolling radius test.

3. The commercial vehicle tire mechanical property testing method based on full vehicle testing according to claim 1, characterized in that: The pre-test includes: Perform pre-positioning operation on the test vehicle to obtain the pre-positioning speed and target test speed; The tire speed and the real instantaneous speed of the vehicle under uniform speed and braking conditions are obtained by using the six-component wheel force and the gyroscope, and the tire slip rate is calculated. Compare the front speed and the initial target test speed when the tire slip rate is 0 to determine whether it meets the requirements. If it does not meet the requirements, repeat the preceding operations until it meets the requirements; The target test speed when the requirements are met is recorded as the braking condition parameter.

4. The commercial vehicle tire mechanical property testing method based on full vehicle testing according to claim 2, characterized in that: The tire cornering characteristics test includes: Based on the second operational data, the test vehicle is driven in a straight line at a constant speed for a period of time. The steering wheel is then turned left at a constant speed to a maximum lateral acceleration. The maximum steering wheel angle is maintained for a period of time, and then the steering wheel is returned to the initial position at the same speed. This is repeated multiple times. The measuring instrument measures the change in wheel posture and the forces and moments acting on the tires. Based on the second operation data, the test vehicle is driven in a straight line at a constant speed for a period of time, and then the steering wheel is turned right at a constant speed to a maximum lateral acceleration. The maximum steering wheel angle is maintained for a period of time, and then the steering wheel is returned to the initial position at the same speed, and this is repeated multiple times; a measuring instrument is used to measure the change in wheel posture and the force and torque applied to the tire; The tire longitudinal slip characteristics test includes: According to the second operating data and the braking condition parameters, the vehicle is accelerated to a certain speed, then shifted into neutral, and then coasted to a certain speed, then braked with a certain braking force until the wheel to be tested is completely locked, and this is repeated multiple times; Measuring the wheel posture change and the forces and moments acting on the tire using the measuring instrument; The tire side slip composite characteristic test includes: Based on the second operating data and the braking condition parameters, the vehicle is driven at a constant speed around a circle of a certain radius, and braking is performed with a certain braking force until the wheel to be tested is completely locked, and the test is repeated multiple times. The same test is performed in the opposite direction and repeated multiple times. The measuring instrument measures the wheel posture change and the force and torque applied to the tire.

5. The commercial vehicle tire mechanical property testing method based on full vehicle testing according to claim 2, characterized in that: The tire lateral relaxed length test includes: According to the second operation data, after the vehicle has been driving in a straight line at a constant speed for a period of time, a steering wheel frequency sweep test is performed at a certain frequency. The vehicle load is changed and the same frequency sweep test is performed multiple times. Measuring the wheel posture change and the forces and moments acting on the tire using the measuring instrument; The lateral slack length of the tire is calculated based on the second operation data and the obtained second round test data.

6. The commercial vehicle tire mechanical property testing method based on full vehicle testing according to claim 2, characterized in that: The tire effective rolling radius test includes: Based on the second operation data, the vehicle is driven in a straight line at a plurality of constant speeds, the vehicle load is changed, and the same test is repeated multiple times; Measuring the wheel posture change and the forces and moments acting on the tire using the measuring instrument; The effective rolling radius of the tire is calculated based on the second operating data and the obtained second round of test data.

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