Commercial vehicle tire mechanical property test method based on whole vehicle test

Abstract

The invention relates to the technical field of tire characteristic testing, in particular to a commercial vehicle tire mechanical characteristic testing method based on a whole vehicle test, which comprises the following steps of: acquiring a plurality of tires which are qualified through a rack test, and mounting the tires and a measuring instrument on a whole vehicle for testing; performing a plurality of preset operations on the whole vehicle for testing to obtain first operation data and first round of test data; comparing the first operation data with the first round of test data, and calibrating the first operation data to obtain second operation data; performing a pre-test on the to-be-tested whole vehicle to obtain test working condition parameters; performing a mechanical property test according to the test working condition parameters and the second operation data to obtain corresponding second-round test data; and obtaining mechanical property parameters of the tire according to the second operation data and the second round of test data. The tire stress is adjusted by adjusting the whole vehicle load in the whole vehicle test, the loading capacity required by the mechanical property test of the commercial vehicle tire is met, and a bench test is not needed.

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 only contact part between the vehicle and the ground, the performance of the tire has a crucial impact on the vehicle's driving performance, safety, comfort, fuel economy, etc. Especially in the field of commercial vehicles, excellent tire performance is extremely important to the performance of the entire vehicle. Therefore, obtaining a complete set of tire mechanical property data to build a tire model is of great significance to tire research and development. The maximum loading capacity of the current tire mechanical property test bench is basically below 30KN, which can only cover the mechanical property test of passenger car and a small number of light truck tires, and cannot be used for mechanical property test of commercial vehicle tires.

[0003] For example, Chinese patent application publication number: CN102435449A discloses a composite four-bar tire mechanical properties testing machine, including an arc guide rail device composed of a base hydraulic cylinder and an arc guide rail, a composite four-bar mechanism assembly composed of a base, four connecting rods, a large rocker mechanism, and a small rocker mechanism, a vertical loading slide plate part 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 property 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 property 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 that the maximum loading capacity of indoor bench tests used in the prior art is insufficient and cannot be used for mechanical property testing of commercial vehicle tires.

[0006] To achieve the above object, 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] Arrange measuring instruments on the configured vehicle, including six-component wheel force sensors, vehicle-mounted K&C test equipment, dual-axis speed sensors, gyroscopes, torque steering wheels, and altimeters to obtain test data of the vehicle and tires while driving;

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

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

[0011] For the tire to be tested, the tire to be tested is configured on a test vehicle that has passed the stability judgment;

[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] Based on the test condition parameters and the second operation data, several mechanical property tests are performed on the test vehicle equipped with the tire to be tested to obtain corresponding second round 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 constant speed driving performance test and a vehicle turning performance test.

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

[0019] Screening the available first operation data and first round test data, and excluding wild point 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 whole vehicle is determined based on the maximum deviation value.

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

[0024] If the maximum deviation value is less than or equal to the set threshold value, the test stability of the whole vehicle is determined to be qualified;

[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 a number of maximum deviation values, and the number of maximum deviation values ​​are processed to obtain regression values.

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

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

[0028] Furthermore, the pre-test includes:

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

[0030] The tire slip rate is calculated by using the six-component force of the wheel and the gyroscope to obtain the tire speed and the real instantaneous speed of the vehicle under uniform speed driving 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 record meets the requirements is the braking condition parameter.

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

[0035] According to the second operation data, after the test vehicle drives straight at a constant speed for a period of time, the steering wheel is turned left at a constant speed to the maximum lateral acceleration, and 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 to obtain the measurement instrument to measure the wheel posture change and the force and torque applied to the tire;

[0036] According to the second operation data, after the whole vehicle is driven straight at a constant speed for a period of time, 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 wheel posture change and the force and torque applied to the tire;

[0037] The tire longitudinal slip characteristics test includes:

[0038] According to the second operation data and the braking condition parameters, the vehicle is accelerated to a certain speed and then shifted into neutral gear, and then the vehicle is coasted to a certain speed and 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 is used to measure the change in wheel posture and the forces and moments acting on the tire.

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

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

[0042] Measuring the wheel posture change and the force and moment exerted on the tire according to the measuring instrument;

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

[0044] According to the second operation data, after the vehicle has been running straight at a constant speed for a period of time, a steering wheel frequency sweep test is performed at a certain frequency, and the vehicle load is changed and the same frequency sweep test is performed repeatedly;

[0045] Measuring the wheel posture change and the force and moment exerted on the tire according to 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] According to the second operation data, the vehicle is driven in a straight line at a plurality of uniform speeds, the vehicle loading is changed, and the same test is performed repeatedly;

[0049] Measuring the wheel posture change and the force and moment exerted on the tire according to the measuring instrument;

[0050] The effective rolling radius of the tire is calculated based on the second operation data and the obtained second round 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 make full use of the existing whole vehicle testing equipment by obtaining the mechanical property test data for building a tire model based on the 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 the mechanical property testing of commercial vehicle tires.

[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 error caused by the whole vehicle test.

[0053] Furthermore, the present invention determines the test condition parameters required for partial mechanical property testing by performing a pre-test on the whole 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 It is a flow chart of the commercial vehicle tire mechanical property testing method based on whole vehicle testing of the present invention;

[0056] Figure 2 It is a schematic diagram of the left-side bias characteristic test;

[0057] Figure 3 It is a schematic diagram of the 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 only used to explain the present invention and are not used 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 protection scope 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 drawings. This is merely 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] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0063] See also Figure 1 As shown, Figure 1The flowchart of the commercial vehicle tire mechanical property testing method based on the whole vehicle test is as follows. Specifically, the embodiment of the present invention provides a commercial vehicle tire mechanical property testing method based on the 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 tire pressure requirements, dynamic balance requirements, etc. for 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 wheel six-component force sensor, a vehicle-mounted K&C test equipment, 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 force sensor of the wheel, the wheel turning angle and roll angle measured by the on-board K&C test equipment, the wheel slip angle measured by the dual-axis speed sensor, the vehicle instantaneous speed measured by the gyroscope, and the vehicle 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 operation data and the first round of test data, the test stability of the whole vehicle is determined, and the first operation data is calibrated according to the result of the test stability to obtain the second operation 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 implementation, 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 and the first operation data (60 km / h). The real instantaneous speed of the test vehicle is obtained every 3 seconds during the above-mentioned constant speed straight driving process through the gyroscope. The maximum |60-real 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 recorded as 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 does not have a single consistency, repeat step S31 10 times to drive 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 to obtain the maximum speed deviation value = 60-real instantaneous speed, and then obtain

[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 implementation, step S32, vehicle turning performance test includes:

[0078] Determine the steering wheel transmission ratio of the test vehicle, record the transmission ratio as S, drive straight at a constant speed of V1 for 30 seconds, turn the steering wheel 60° at a constant speed to the right, keep the above steering wheel angle for 1 second, then return the steering wheel to the initial position at the same speed, drive straight at a constant speed for 30 seconds, then turn the steering wheel 60° at a constant speed to the left, keep the above steering wheel angle for 1 second, then return the steering wheel to the initial position at the same speed, obtain the tire angle when the steering wheel is turned 60° to the left and 60° 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 driving of the above-mentioned test vehicle does not have single-time consistency, then repeat 10 times the steps of driving in a straight line at a constant speed of V1 for 30 seconds, turning the steering wheel right at a constant speed of 60°, keeping the above-mentioned steering wheel angle for 1 second, and then returning the steering wheel to the initial position at the same speed, and then driving in a straight line at a constant speed for 30 seconds, turning the steering wheel left at a constant speed of 60°, keeping the above-mentioned 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 operation, 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 vehicle and the tire angle tested by the on-board K&C test equipment.

[0082] Specifically, in step S3, it also includes:

[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 value between the first operation data and the first round of test data according to the comparison calculation;

[0086] Step S303: determining the test stability of the whole 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 the implementation, 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 can be understood 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, for the tire to be tested, placing the tire to be tested on a test vehicle that has passed the stability judgment;

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

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

[0093] Specifically, the pre-tests include:

[0094] The test vehicle is accelerated to a certain speed (pre-set as the pre-speed V0), put into neutral, and glides to a corresponding speed (the speed is the target test speed V2, V0>V2) and then braked with a braking force of 50N / s. The tire speed when no braking force is applied and the tire speed when braking force is applied are obtained from the six-component force of the wheel and the gyroscope during the process from the pre-speed V0 to the stop of the test vehicle. According to the tire slip rate formula, it is as follows:

[0095]

[0096] The target test speed V2 when the tire slip rate is equal to 0 for the first time (that is, when the tire speed when the braking force is applied is the same as the tire speed when no braking force is applied for the first time) 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 condition parameters to obtain corresponding second round test data;

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

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

[0100] Specifically, the cornering characteristics test includes:

[0101] After the test vehicle has been driving 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 driving position) at the same speed. The test is repeated three times.

[0102] Please refer to the schematic diagram of the left steering wheel working condition test input for the ideal test (i.e. the test vehicle transmission ratio S = 10, the steering wheel angle is 120°, and the vehicle speed remains unchanged during the test) Figure 2 As shown, the second round of test data measured during the test includes wheel posture 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).

[0103] After the vehicle has been driving in a straight line at a constant speed of V1 for a period of time, the steering wheel is turned right 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.

[0104] Please refer to the schematic diagram of the right-hand steering wheel test input for the ideal test (i.e., the test vehicle transmission ratio S=10, the steering wheel angle is 120°, and the vehicle speed remains unchanged during the test) Figure 3 As shown, the second round of test data measured during the test includes wheel posture 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).

[0105] Specifically, the longitudinal sliding characteristics test includes:

[0106] The test vehicle is accelerated to the pre-speed V0, put into neutral, and when it glides to the target test speed V2, it is braked with a braking force of 50N / s until the wheels of the test vehicle are completely locked, that is, the tire slip rate is from 0 to -100%, and the test is repeated three times.

[0107] For the test input diagram of the ideal state (i.e., target speed V2 = 60 km / s, the wheels of the vehicle to be tested can be completely locked after braking), please refer to Figure 4 As shown, the second round of test data measured during the test includes wheel posture 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).

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

[0109] The test vehicle is driven at a constant speed of V2 around a circle with a radius of 100m, and braked with a braking force of 50N / s until the wheels of the test vehicle are completely locked, that is, the tire slip rate is from 0 to -100%, and the test is repeated three times. The same test is carried out in the opposite direction around a circle with a radius of 100m, and the test is repeated three times.

[0110] The same test is carried out on two other circles with radii of 150m and 200m respectively. The second round test data measured during each test includes wheel attitude changes (side 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 return moment Mz).

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

[0112] After the test vehicle has been driving in a straight line at a constant speed of V1 for a period of time, a steering wheel sweep test with frequencies of 1Hz, 2Hz, 3Hz, 4Hz, and 5Hz is performed. The vehicle load is increased twice, 1000kg each time, and the same sweep test is performed respectively. The second round of test data measured during the test includes wheel posture changes (side 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 return moment Mz).

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

[0114] The test vehicle drove in a straight line at a constant speed at 6 speeds (V1-40 km / h, V1-20 km / h, V1, V1+20km / h, V1+40km / h, V1+80km / h), and the vehicle load was increased twice, each time by 1000kg, and the same test was carried out respectively. The second round of test data measured during the test included the changes in wheel posture (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 relaxation 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 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 relaxation 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] Then the lag time of the tire lateral force (relative to the sideslip angle) is Among them, 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 relaxation length of the tire = V1×Δt.

[0124] Specifically, the calculation method of the effective rolling radius is:

[0125] The wheel speed in the second round of test data obtained in the effective rolling radius test is recorded as Ω, the unit is rad / s, and the vehicle speed is recorded as Vx, the unit is 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 moment exerted on the tire, which is the cornering characteristic test data of the test tire.

[0127] Specifically, in the longitudinal slip characteristics 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 characteristics test data of the test tire.

[0128] Specifically, the second round of test data obtained in the cornering and longitudinal slip composite characteristic test includes the wheel posture change and the force and moment exerted on the tire, namely, the cornering and longitudinal slip composite characteristic test data of the test tire.

[0129] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A commercial vehicle tire mechanical properties testing method based on whole vehicle testing, characterized in that: include: Obtain several tires that have passed the bench test and configure the tires to be tested on the test vehicle; Arrange measuring instruments on the configured vehicle, including six-component wheel force sensors, vehicle-mounted K&C test equipment, dual-axis speed sensors, gyroscopes, torque steering wheels, and altimeters to obtain test data of the vehicle and tires while driving; Performing a number of preset operations on the vehicle to be tested, and acquiring corresponding first operation data and first round test data according to the preset operations; wherein, based on the first operation data and the first round of test data, the test stability of the whole vehicle is determined, and the first operation data is calibrated according to the result of the test stability to obtain the second operation data; For the tire to be tested, the tire to be tested is configured on the test vehicle that has passed the stability judgment; 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; Based on the test condition parameters and the second operation data, several mechanical property tests are performed on a test vehicle equipped with the tire to be tested to obtain corresponding second round 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 whole vehicle testing according to claim 1, characterized in that: The several mechanical property 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 whole vehicle testing according to claim 1, characterized in that: The plurality of preset operations include a vehicle constant speed driving performance test and a vehicle turning performance test.

4. The commercial vehicle tire mechanical property testing method based on whole vehicle testing according to claim 1, characterized in that: The calibrating the first operation data according to the result of the stability test to obtain the second operation data comprises: Screening the available first operation data and first round test data, and excluding wild point 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; The test stability of the whole vehicle is determined based on the maximum deviation value.

5. The commercial vehicle tire mechanical property testing method based on whole vehicle testing according to claim 4, characterized in that: The method of judging the test stability of the whole vehicle based on the maximum deviation value includes: If the maximum deviation value is less than or equal to the set threshold value, the test stability of the whole vehicle is determined to be qualified; 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 a number of maximum deviation values, and the number of maximum deviation values ​​are processed to obtain regression values.

6. The commercial vehicle tire mechanical property testing method based on whole vehicle testing according to claim 5, characterized in that: After obtaining the regression value, the method further includes: The first operation data is calibrated based on the regression value to obtain the second operation data.

7. The commercial vehicle tire mechanical property testing method based on whole vehicle testing according to claim 1, characterized in that: The pre-tests include: Perform pre-positioning operation on the test vehicle to obtain the pre-positioning speed and the target test speed; The tire speed and the real instantaneous speed of the vehicle under uniform speed driving and braking are obtained by using the six-component force of the wheel 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 record meets the requirements is the braking condition parameter.

8. The commercial vehicle tire mechanical property testing method based on whole vehicle testing according to claim 2, characterized in that: The tire cornering characteristics test includes: According to the second operation data, after the test vehicle drives straight at a constant speed for a period of time, the steering wheel is turned left at a constant speed to the maximum lateral acceleration, and 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 to obtain the measurement instrument to measure the wheel posture change and the force and torque applied to the tire; According to the second operation data, after the whole vehicle is driven straight at a constant speed for a period of time, 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 wheel posture change and the force and torque applied to the tire; The tire longitudinal slip characteristics test includes: According to the second operation data and the braking condition parameters, the vehicle is accelerated to a certain speed and then shifted into neutral gear, and then the vehicle is coasted to a certain speed and 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 force and moment exerted on the tire according to the measuring instrument; The tire side slip composite characteristic test includes: According to the second operation data and the braking condition parameters, the vehicle is driven at a constant speed around a circle of a certain radius, and braked with a certain braking force until the wheel to be tested is completely locked, and the test is repeated multiple times, and the same test is performed in the opposite direction, and repeated multiple times; The measuring instrument is used to measure the change in wheel posture and the forces and moments acting on the tire.

9. The commercial vehicle tire mechanical property testing method based on whole vehicle testing according to claim 2, characterized in that: The tire lateral relaxation length test includes: According to the second operation data, after the vehicle has been running straight at a constant speed for a period of time, a steering wheel frequency sweep test is performed at a certain frequency, and the vehicle load is changed and the same frequency sweep test is performed repeatedly; Measuring the wheel posture change and the force and moment exerted on the tire according to 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.

10. The commercial vehicle tire mechanical property testing method based on whole vehicle testing according to claim 2, characterized in that: The tire effective rolling radius test includes: According to the second operation data, the vehicle is driven in a straight line at a plurality of uniform speeds, the vehicle loading is changed, and the same test is performed repeatedly; Measuring the wheel posture change and the force and moment exerted on the tire according to the measuring instrument; The effective rolling radius of the tire is calculated based on the second operation data and the obtained second round test data.

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