Method for testing the coefficient of dry adhesion of a vehicle tire

Abstract

The application discloses a kind of test methods of the dry adhesion coefficient of automobile tire, comprising: determining test speed range;Towing vehicle travels in test section with first output power, the surface temperature of tire and the speed of towing vehicle are detected;Calculate dynamic adhesion coefficient, correct dynamic adhesion coefficient, and the corrected dynamic adhesion coefficient is recorded as standard dynamic adhesion coefficient;Determine correction coefficient;Obtain the surface roughness of the road on the driving path of the tire to be tested on trailer, the longitudinal force and lateral force received by trailer;Calculate the standard dynamic adhesion coefficient of the tire to be tested, and the standard dynamic adhesion coefficient is corrected using correction coefficient to obtain the dry adhesion coefficient of tire.The application establishes the corresponding relationship between real-time roughness and correction coefficient, compensates the adhesion deviation caused by the change of road roughness, and can meet the high-precision demand of tire basic performance evaluation and road safety monitoring.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of tire detection, and more particularly, to a test method for dry adhesion coefficient of automobile tire. BACKGROUND

[0002] With the continuous development of science and technology, the driving speed of vehicles is getting faster and faster, and the requirement for the tire grip performance is getting higher and higher. As an important index for measuring the tire grip performance, whether the tire dry adhesion coefficient is accurate directly relates to the stability and safety of vehicle driving. Therefore, how to accurately obtain the tire dry adhesion coefficient becomes an important research direction in the field of vehicle testing technology.

[0003] In the dry land test environment, the existing tire dry adhesion coefficient detection experiment sets a detection device on a trailer, and calculates the tire dry adhesion coefficient of the tire to be tested on the trailer by detecting the parameters of the trailer. However, the existing technology ignores the influence of the dynamic change of the surface roughness of the road on the measured tire dry adhesion coefficient in the detection process. In the dry land environment, the slight change of the roughness of the road will directly lead to the change of the friction characteristics of the tire to be tested, so that the measured tire dry adhesion coefficient still has a large deviation from the actual tire dry adhesion coefficient, and the accuracy of the detection result is insufficient.

[0004] Therefore, the existing technology has defects and needs to be improved. SUMMARY

[0005] In view of the above problems, the purpose of the present application is to provide a test method for dry adhesion coefficient of automobile tire, so as to solve the problem that the dynamic change of the surface roughness of the road is ignored in the existing technology, which influences the measured tire dry adhesion coefficient. In the dry land environment, the slight change of the roughness of the road will directly lead to the change of the friction characteristics of the tire to be tested, so that the measured tire dry adhesion coefficient still has a large deviation from the actual tire dry adhesion coefficient, and the accuracy of the detection result is insufficient.

[0006] The first aspect of the present application provides a test method for dry adhesion coefficient of automobile tire, comprising:

[0007] obtaining the static adhesion coefficient of the towing vehicle and the surface roughness of the road in the test section, and determining the test speed range according to the static adhesion coefficient of the towing vehicle and the surface roughness;

[0008] selecting a first test speed as the detection speed in the tire dry adhesion coefficient detection process in the test speed range, determining the first output power of the towing vehicle according to the first test speed, and driving the towing vehicle in the test section at the first output power, and continuously detecting the surface temperature of the tire and the speed of the towing vehicle;

[0009] The dynamic adhesion coefficient of the tractor is calculated during driving, the dynamic adhesion coefficient of the tractor is corrected according to the speed of the tractor and the surface temperature of the tire, and the corrected dynamic adhesion coefficient of the tractor is recorded as the standard dynamic adhesion coefficient of the tractor;

[0010] The surface roughness of the road surface on the driving path of the tractor tire is obtained, and the correction coefficient is determined according to the static adhesion coefficient of the tractor, the standard dynamic adhesion coefficient of the tractor, and the surface roughness;

[0011] The tire to be tested is fixed at the corresponding position of the trailer, the tractor drives the trailer at the first test speed on the test road section, and the surface roughness of the road surface on the driving path of the tire to be tested on the trailer, the longitudinal force and the lateral force received by the trailer are obtained;

[0012] The dynamic adhesion coefficient of the tire to be tested is calculated according to the longitudinal force and the lateral force received by the trailer, the standard dynamic adhesion coefficient of the tire to be tested is obtained by correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested, and the standard dynamic adhesion coefficient of the tire to be tested is corrected using the correction coefficient and the test result is output.

[0013] As a preferred technical scheme of the test method of the dry adhesion coefficient of the automobile tire, the static adhesion coefficient of the tractor and the surface roughness of the road surface in the test road section are obtained, and the test speed range is determined according to the static adhesion coefficient of the tractor and the surface roughness, comprising:

[0014] The tractor tire is tested on a test bench, a slip rate of 5%-8% is applied, the longitudinal force F x静 , the lateral force F y静 and the vertical load F z静 of the tractor tire in the test bench test are collected, and the static adhesion coefficient of the tractor is calculated;

[0015] The surface roughness range of the road surface in the test road section is obtained, and the minimum value of the surface roughness of the road surface in the test road section is selected and recorded as the reference roughness;

[0016] The test speed range is determined according to the reference roughness and the static adhesion coefficient of the tractor.

[0017] As a preferred technical scheme of the test method of the dry adhesion coefficient of the automobile tire, the test road section is selected to meet the following conditions:

[0018] The road surface material is asphalt or concrete dry road surface, and the surface has no water, no oil stain, no crack and no protrusion, and the water content of the road surface is less than or equal to 5%;

[0019] In the test section, the length of the effective test section for constant power driving of the tractor is greater than or equal to 300m;

[0020] The surface roughness of the road surface within the test section fluctuated by less than 15%.

[0021] As a preferred technical solution for testing the dry grip coefficient of automobile tires, the step of determining the first output power of the tractor based on the first test speed includes:

[0022] Calculate the air resistance of the tractor during operation based on the first test speed. ;

[0023] Calculate rolling resistance based on the static adhesion coefficient of the tractor. ;

[0024] Calculate the road surface slope resistance based on the average slope of the test section. ;

[0025] According to the air resistance The rolling resistance and the road surface slope resistance Calculate the total driving resistance of the tractor ;in: ;

[0026] Based on the first test speed and the total driving resistance of the tractor... Calculate the first output power P; the formula for calculating the first output power P is: In the formula: For the first test speed, This refers to the transmission efficiency of the tractor.

[0027] As a preferred technical solution for testing the dry grip coefficient of automobile tires, the step of correcting the dynamic grip coefficient of the tractor vehicle based on the speed of the tractor vehicle and the surface temperature of the tires, and recording the corrected dynamic grip coefficient of the tractor vehicle as the standard dynamic grip coefficient of the tractor vehicle, includes:

[0028] The dynamic adhesion coefficient of the tractor is obtained by correcting the dynamic adhesion coefficient of the tractor based on its speed. ;

[0029] The dynamic adhesion coefficient is adjusted based on the tire surface temperature and the speed of the tractor. The standard dynamic adhesion coefficient of the tractor is obtained by making corrections. .

[0030] As a preferred technical scheme of the test method of the dry land adhesion coefficient of the automobile tire, the formula for correcting the dynamic adhesion coefficient of the towing vehicle according to the speed of the towing vehicle is:

[0031] ;

[0032] Wherein: is the dynamic adhesion coefficient of the towing vehicle, is the speed attenuation coefficient, is the driving speed.

[0033] As a preferred technical scheme of the test method of the dry land adhesion coefficient of the automobile tire, the formula for correcting the dynamic adhesion coefficient of the towing vehicle according to the surface temperature of the tire is: Wherein: is the standard dynamic adhesion coefficient of the towing vehicle, is the speed-corrected dynamic adhesion coefficient of the towing vehicle, is the temperature compensation coefficient, is the reference value of the surface temperature of the tire, is the surface temperature of the tire during the test.

[0034] As a preferred technical scheme of the test method of the dry land adhesion coefficient of the automobile tire, the surface roughness of the road on the driving path of the tire of the towing vehicle is obtained, and the correction coefficient is determined according to the static adhesion coefficient of the towing vehicle, the standard dynamic adhesion coefficient of the towing vehicle and the surface roughness, comprising:

[0035] When the towing vehicle drives on the effective test section at the first output power, the real-time roughness of the road on the driving path of the towing vehicle is obtained according to the preset sampling rate ;

[0036] The real-time roughness of the road is one-to-one corresponding to the standard dynamic adhesion coefficient of the towing vehicle ;

[0037] The correction coefficient K is calculated according to the real-time roughness of the road , the static adhesion coefficient of the towing vehicle , and the standard dynamic adhesion coefficient ;

[0038] The correspondence table of the real-time roughness and the correction coefficient K is established and stored.

[0039] As a preferred technical scheme of the test method of the dry land adhesion coefficient of the automobile tire, the formula for correcting the dynamic adhesion coefficient of the towing vehicle according to the surface roughness of the road ​a static adhesion coefficient of the towing vehicle a standard dynamic adhesion coefficient of the towing vehicle a correction coefficient K is calculated, wherein:

[0040] The calculation formula of the correction coefficient K is: ;

[0041] wherein: a real-time roughness of the road on the driving path, a reference roughness, a static adhesion coefficient of the towing vehicle, a standard dynamic adhesion coefficient of the towing vehicle.

[0042] As the preferred technical scheme of the test method of the dry adhesion coefficient of the automobile tire, the dynamic adhesion coefficient of the tire to be tested is calculated according to the longitudinal force and the lateral force received by the trailer, the standard dynamic adhesion coefficient of the tire to be tested is obtained by correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested, the standard dynamic adhesion coefficient of the tire to be tested is corrected by using the correction coefficient, and the test result is output, comprising:

[0043] obtaining the real-time longitudinal force , the real-time lateral force , and the real-time vertical load of the trailer, and calculating the dynamic adhesion coefficients of a plurality of tires to be tested;

[0044] correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested to obtain the standard dynamic adhesion coefficient of the tire to be tested;

[0045] correcting the standard dynamic adhesion coefficient of the tire to be tested according to the correction coefficient K to obtain the dry adhesion coefficients of a plurality of tires to be tested;

[0046] calculating the average value of the dry adhesion coefficients of the tires to be tested and outputting the test result.

[0047] Compared with the prior art, the beneficial effects of the present application are that, in the detection of the dry adhesion coefficient, the towing vehicle needs to keep uniform speed, and the essence of the uniform speed of the towing vehicle is that the output power of the towing vehicle is equal in size and opposite in direction to the resistance received, but since the roughness of the road is not uniform, the speed of the towing vehicle is affected in the driving process, and then the longitudinal force and the lateral force The measurement value of the surface roughness has an influence, so that the change of the surface roughness has an influence on the detection result of the tire dry adhesion coefficient by using the trailer, and the application corrects the detection result according to the real-time surface roughness by establishing the corresponding relationship between the real-time surface roughness and the correction coefficient, so as to increase the accuracy of the detection result of the tire dry adhesion coefficient obtained by the trailer. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 A flow chart of a test method for a dry adhesion coefficient of a tire of a vehicle is shown. DETAILED DESCRIPTION

[0049] In order to more clearly understand the above-mentioned purposes, features and advantages of the application, the application will be further described in detail below in combination with the drawings and specific embodiments. It should be noted that the embodiments of the application and the features in the embodiments can be combined with each other without conflict.

[0050] In the following description, many specific details are set forth in order to provide a thorough understanding of the application, but the application can also be practiced without other different ways from those described herein, and therefore, the scope of protection of the application is not limited by the specific embodiments disclosed below.

[0051] As shown in Figure 1 The application discloses a test method for a dry adhesion coefficient of a tire of a vehicle, comprising:

[0052] Step S1, acquiring the static adhesion coefficient of the towing vehicle and the surface roughness of the road in the test section, and determining the test speed range according to the static adhesion coefficient of the towing vehicle and the surface roughness;

[0053] Step S2, selecting a first test speed as a detection speed in the tire dry adhesion coefficient detection process in the test speed range, determining the first output power of the towing vehicle according to the first test speed, and driving the towing vehicle in the test section at the first output power, and continuously detecting the surface temperature of the tire and the speed of the towing vehicle;

[0054] Step S3, calculating the dynamic adhesion coefficient of the towing vehicle in the driving process, correcting the dynamic adhesion coefficient of the towing vehicle according to the speed of the towing vehicle and the surface temperature of the tire, and recording the corrected dynamic adhesion coefficient of the towing vehicle as the standard dynamic adhesion coefficient of the towing vehicle;

[0055] Step S4, acquiring the surface roughness of the road on the driving path of the tire of the towing vehicle, and determining the correction coefficient according to the static adhesion coefficient of the towing vehicle, the standard dynamic adhesion coefficient of the towing vehicle and the surface roughness;

[0056] Step S5, fixing the tire to be tested on the corresponding position of the trailer, the towing vehicle towing the trailer at the first test speed in the test section, obtaining the surface roughness of the road on the running path of the tire to be tested on the trailer, the longitudinal force and the lateral force received by the trailer;

[0057] Step S6, calculating the dynamic adhesion coefficient of the tire to be tested according to the longitudinal force and the lateral force received by the trailer, correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested to obtain the standard dynamic adhesion coefficient of the tire to be tested, correcting the standard dynamic adhesion coefficient of the tire to be tested using the correction coefficient and outputting the test result.

[0058] In implementation, the laser roughness meter is used to detect the road roughness. The calculation formula of the adhesion coefficient is: Among them: is the longitudinal force along the running direction, is the lateral force perpendicular to the running direction, is the pressure between the tire and the ground, in implementation, the pressure between the tire and the ground can be directly measured by pressure detector and other detection equipment or indirectly obtained by calculation, and the formula is a commonly used formula for those skilled in the art, which will not be described here.

[0059] In detail, in the detection of dry adhesion coefficient, the towing vehicle needs to keep uniform speed, and the essence of the uniform speed of the towing vehicle is that the output power of the towing vehicle is equal in size and opposite in direction to the resistance received. However, due to the uneven roughness of the road, the speed of the towing vehicle will be affected during driving, thereby affecting the measurement values of the longitudinal force and the towing lateral force of the trailer, therefore, the change of the road roughness will affect the detection result of the dry adhesion coefficient of the tire obtained by the trailer, and the present application establishes the corresponding relationship between the real-time roughness and the correction coefficient, and compensates the adhesion deviation caused by the change of the road roughness, thereby increasing the accuracy of the detection result of the dry adhesion coefficient of the tire obtained by the trailer.

[0060] Further, the static adhesion coefficient of the towing vehicle and the surface roughness of the road in the test section are obtained, and the test speed range is determined according to the static adhesion coefficient of the towing vehicle and the surface roughness, including:

[0061] The tires of the towing vehicle are tested on the test bench, a slip rate of 5%-8% is applied, and the longitudinal force F x静 , the lateral force F y静 and the vertical load F z静, the static adhesion coefficient of the tractor is calculated according to the calculation formula of the adhesion coefficient and is averaged, and is recorded as the static adhesion coefficient of the tractor ;

[0062] The surface roughness range of the road surface in the test section is obtained, the minimum value of the surface roughness of the road surface in the test section is selected, and is recorded as the reference roughness.

[0063] The test speed range is determined according to the reference roughness and the static adhesion coefficient of the tractor.

[0064] In implementation, the MTS Fla-Trac tire bench is used to simulate the asphalt dry road surface (the friction material of the bench needs to be the same as the material of the test road surface), and the slip rate between the tire and the ground is 5%-8%, which conforms to the actual situation of the tire driving on the asphalt road surface. The test parameters of the bench are set as follows: the vertical load is the same as the load of the tractor on the ground during driving, three groups of F x静 and lateral force F y静 are collected, the average value of the adhesion coefficient is calculated, and is recorded as the static adhesion coefficient. The test speed range is: the speed range in which the relative slip rate of the tire of the tractor and the ground is 6% or less, in which range, the friction between the tire and the bench friction material conforms to the actual situation, the relative stability of the speed of the tractor can be met after the power of the tractor is determined, and the reference roughness is the minimum value of the surface roughness of the road surface in the test section, the reference roughness can meet the relative stability of the speed of the tractor, and other values of the surface roughness of the road surface in the test section can also meet the relative stability of the speed of the tractor. In the test speed range, the corresponding first test speed is selected according to the actual situation, in the embodiment of the present application, the first test speed is the middle value of the test speed range, considering the economy and the actual driving speed.

[0065] Further, the present application ensures that the static adhesion coefficient obtained can truly reflect the actual situation by matching the friction material in the bench test process with the actual road surface, and matching the tire pressure and tire temperature with the existing conditions, thereby laying an accurate data foundation for the determination of the subsequent correction coefficient, and increasing the accuracy of the detection result of the dry road adhesion coefficient of the tire.

[0066] Further, the test section is selected to meet the following conditions:

[0067] The road surface material is an asphalt or concrete dry road surface, and the surface is free of water, oil stains, cracks and protrusions, and the water content of the road surface is less than or equal to 5%;

[0068] In the test section, the length of the constant-power driving effective test section of the tractor is greater than or equal to 300m;

[0069] The fluctuation amplitude of the surface roughness of the road surface in the test section is less than 15%.

[0070] Further, the calculation formula of the fluctuation amplitude is:

[0071] .

[0072] Further, the first output power of the towing vehicle is determined according to the first test speed, comprising:

[0073] The air resistance of the towing vehicle in the driving process is calculated according to the first test speed ;

[0074] The rolling resistance is calculated according to the static adhesion coefficient of the towing vehicle ;

[0075] The road slope resistance is calculated according to the average slope of the test section ;

[0076] The total driving resistance of the towing vehicle is calculated according to the air resistance , the rolling resistance and the road slope resistance ; wherein: ; wherein: ;

[0077] The first output power P is calculated according to the first test speed and the total driving resistance of the towing vehicle ; the calculation formula of the first output power P is: , wherein: is the first test speed, is the transmission efficiency of the towing vehicle (which is a fixed value, and the specific value is calibrated according to the model of the towing vehicle).

[0078] In implementation, the calculation formula of the air resistance is: , wherein: is the wind resistance coefficient of the towing vehicle (which is a fixed value, only related to the external structure of the towing vehicle), is the windward area of the towing vehicle, which is also a fixed value, measured according to the actual external structure of the towing vehicle, with the unit of square meter, is the air density, obtained by detecting the actual environment, with the unit of kg / m 3 , is the first test speed with the unit of m / s. The calculation formula of the rolling resistance is: , wherein: is the static adhesion coefficient, m is the curb weight of the towing vehicle with the unit of kg, and g is the acceleration of gravity. The calculation formula of the road slope resistance is: ,in: The average slope of the test section was detected using an inclination sensor.

[0079] Furthermore, the dynamic adhesion coefficient of the tractor is corrected based on the tractor's speed and tire surface temperature. The corrected dynamic adhesion coefficient is recorded as the standard dynamic adhesion coefficient of the tractor, including:

[0080] The speed-corrected dynamic adhesion coefficient of the tractor is obtained by correcting the dynamic adhesion coefficient of the tractor based on its speed. The formula for correcting the dynamic adhesion coefficient based on the speed of the tractor is as follows: ,in: For the dynamic adhesion coefficient of the tractor, For velocity attenuation coefficient, The speed is measured in km / h.

[0081] The dynamic adhesion coefficient is adjusted based on the tire surface temperature and the tractor speed. The standard dynamic adhesion coefficient of the tractor is obtained by making corrections. The dynamic adhesion coefficient is adjusted based on the tire surface temperature and the tractor speed. The corrected formula is: ,in: To adjust the dynamic adhesion coefficient based on the speed of the tractor, Temperature compensation coefficient, This is a reference value for the surface temperature of the tire, in °C. The temperature measured during the test is the surface temperature of the tire, expressed in °C.

[0082] Furthermore, the velocity decay coefficient and temperature compensation coefficient The aim is to correct the measured adhesion coefficient based on temperature and speed, making the result closer to the actual adhesion coefficient and speed decay coefficient. and temperature compensation coefficient The values ​​are all configured by the computer based on actual vehicle speed, tire performance, and other factors. In this embodiment of the invention, the speed attenuation coefficient... The value is 0.002, temperature compensation coefficient. The value is 0.001. It should be noted that as the tire surface temperature increases, the tire surface will gradually soften, increasing adhesion. As the temperature continues to increase, the tire surface will melt and the adhesion will decrease. Therefore, the reference value for the tire surface temperature needs to be selected according to the actual situation. In this embodiment of the invention, the reference value for the tire surface temperature is 25°C.

[0083] Further, the present application corrects the dry adhesion force coefficient by speed and temperature, so as to compensate the influence of speed and temperature on the dry adhesion force coefficient, and solves the dynamic data deviation problem caused by ignoring environmental factors in the prior art.

[0084] Further, the surface roughness of the road surface on the driving path of the tractor tire is obtained, and the correction coefficient is determined according to the static adhesion force coefficient, the standard dynamic adhesion force coefficient of the tractor and the surface roughness, comprising:

[0085] When the tractor drives on the effective test section at the first output power, the real-time roughness of the road surface on the driving path of the tractor is obtained according to a preset sampling rate ;

[0086] The real-time roughness of the road surface corresponds to the standard dynamic adhesion force coefficient of the tractor ;

[0087] The correction coefficient K is calculated according to the real-time roughness of the road surface , the static adhesion force coefficient of the tractor and the standard dynamic adhesion force coefficient .

[0088] The correspondence table of the real-time roughness of the road surface and the correction coefficient K is established and stored.

[0089] In implementation, the roughness of the road surface on the driving path is collected in real time by a laser roughness meter; the preset sampling rate is in the range of 10-20 Hz, and the specific value is determined according to actual conditions, and the measurement accuracy is ±0.01 μm.

[0090] Further, the correction coefficient K is calculated according to the real-time roughness of the road surface , the static adhesion force coefficient of the tractor and the standard dynamic adhesion force coefficient , wherein:

[0091] The calculation formula of the correction coefficient K is: ;

[0092] Wherein: is the real-time roughness of the road surface on the driving path, is the reference roughness, is the static adhesion force coefficient of the tractor, is the standard dynamic adhesion force coefficient of the tractor.

[0093] Further, the dynamic adhesion coefficient of the tire to be tested is calculated according to the longitudinal force and the lateral force received by the trailer, the dynamic adhesion coefficient of the tire to be tested is corrected according to the speed of the trailer and the surface temperature of the tire to be tested to obtain the standard dynamic adhesion coefficient of the tire to be tested, the standard dynamic adhesion coefficient of the tire to be tested is corrected using the correction coefficient and the test result is output, including:

[0094] obtaining the real-time longitudinal force of the trailer , the real-time lateral force and the real-time vertical load , and calculating the dynamic adhesion coefficient of the tire to be tested;

[0095] correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested to obtain the standard dynamic adhesion coefficient of the tire to be tested;

[0096] correcting the standard dynamic adhesion coefficient of the tire to be tested according to the correction coefficient K to obtain the dry adhesion coefficient of the tire to be tested;

[0097] calculating the average value of the dry adhesion coefficient of the tire to be tested and outputting the test result.

[0098] In implementation, the process of correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested is the same as the process of correcting the dynamic adhesion coefficient of the tractor according to the speed of the tractor and the surface temperature of the tire, only the adhesion coefficient is different, which will not be repeated here. The product of the correction coefficient K and the standard dynamic adhesion coefficient of the tire to be tested is recorded as the dry adhesion coefficient of the tire to be tested.

[0099] Those skilled in the art can understand that all or part of the steps of the above-mentioned method embodiments can be completed by program instruction related hardware, the above-mentioned program can be stored in a computer readable storage medium, the program executes the steps including the above-mentioned method embodiments when executing; and the above-mentioned storage medium includes mobile storage device, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disc or optical disc and various storage program code medium.

[0100] Alternatively, the above-mentioned integrated unit of the present application, if realized in the form of a software function module and sold or used as an independent product, can also be stored in a computer-readable storage medium. Based on such understanding, the technical solutions of the embodiments of the present application can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: mobile storage devices, ROM, RAM, magnetic disks or optical disks, and various media that can store program codes.

Claims

1. A method of testing the dry adhesion coefficient of a vehicle tire, characterized in that, The method comprises the following steps: acquiring the static adhesion coefficient of the towing vehicle and the surface roughness of the road in the test section, and determining the test speed range according to the static adhesion coefficient of the towing vehicle and the surface roughness; selecting a first test speed as the detection speed in the tire dry adhesion coefficient detection process in the test speed range, determining the first output power of the towing vehicle according to the first test speed, and driving the towing vehicle at the first output power on the test section to continuously detect the surface temperature of the tire and the speed of the towing vehicle; calculating the dynamic adhesion coefficient of the towing vehicle during driving, correcting the dynamic adhesion coefficient of the towing vehicle according to the speed of the towing vehicle and the surface temperature of the tire, and recording the corrected dynamic adhesion coefficient of the towing vehicle as the standard dynamic adhesion coefficient of the towing vehicle; acquiring the surface roughness of the road on the driving path of the tire of the towing vehicle, and determining the correction coefficient according to the static adhesion coefficient of the towing vehicle, the standard dynamic adhesion coefficient of the towing vehicle and the surface roughness; fixing the tire to be tested on the corresponding position of the trailer, driving the trailer at the first test speed on the test section, and acquiring the surface roughness of the road on the driving path of the tire to be tested on the trailer, the longitudinal force and the lateral force received by the trailer; calculating the dynamic adhesion coefficient of the tire to be tested according to the longitudinal force and the lateral force received by the trailer, correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested to obtain the standard dynamic adhesion coefficient of the tire to be tested, correcting the standard dynamic adhesion coefficient of the tire to be tested using the correction coefficient and outputting the test result.

2. The method for testing the adhesion coefficient on dry ground of motor vehicle tyres according to claim 1, characterised in that, The method comprises the following steps: The tractor tire is subjected to bench test, 5%-8% slip rate is applied, the longitudinal force F x静 , lateral force F y静 and vertical load F z静 of the tractor tire in the bench test are collected, and the static adhesion coefficient of the tractor is calculated; acquiring the surface roughness range of the road in the test section, selecting the minimum value of the surface roughness of the road in the test section as the reference roughness, and determining the test speed range according to the reference roughness and the static adhesion coefficient of the towing vehicle. The test section meets the following conditions:

3. The method for testing the adhesion coefficient on dry ground of tyres for motor vehicles, as claimed in claim 2, characterized in that, the road surface material is asphalt or concrete dry road surface, and the surface is free of water, oil stains, cracks and protrusions, and the water content of the road surface is less than or equal to 5%; in the test section, the length of the effective test section of the towing vehicle driving at a constant power is greater than or equal to 300m; the fluctuation range of the surface roughness of the road in the test section is less than 15%. The method comprises the following steps:

4. The method of testing the dry adhesion coefficient of a vehicle tire according to claim 1, characterized in that, The method comprises the following steps: calculating the air resistance of the towing vehicle during travel according to the first test speed ; Calculating rolling resistance from static coefficient of friction of a towing vehicle ; Calculating road surface slope resistance from average slope of test section ; The air resistance is calculated according to the following formula: The rolling resistance is calculated according to the following formula: The road slope resistance is calculated according to the following formula: The total driving resistance of the towing vehicle is calculated according to the following formula: Wherein: ; According to the first test speed and the total travel resistance of the tractor The first output power P is calculated, and the calculation formula of the first output power P is: , wherein: is the first test speed, is the transmission efficiency of the tractor.

5. The method for testing the adhesion coefficient on dry ground of motor vehicle tyres according to claim 4, characterised in that, The method comprises the following steps: correcting the dynamic adhesion coefficient of the towing vehicle according to the speed of the towing vehicle to obtain a speed-corrected dynamic adhesion coefficient of the towing vehicle ; correcting the dynamic adhesion force coefficient of the tractor according to the surface temperature of the tire correcting the dynamic adhesion force coefficient of the tractor according to the surface temperature of the tire .

6. The method for testing the adhesion coefficient on dry ground of motor vehicle tyres according to claim 5, characterised in that, The formula for correcting the dynamic adhesion coefficient of the towing vehicle according to the speed of the towing vehicle is: ； wherein: is the dynamic adhesion coefficient of the towing vehicle, is the speed decay coefficient, is the driving speed.

7. The method of testing the dry adhesion coefficient of a vehicle tire according to claim 5, characterized in that, correcting the dynamic adhesion coefficient of the tractor with the surface temperature of the tyre The formula to be corrected is: where: C is the standard dynamic adhesion coefficient of the tractor, C is the speed corrected dynamic adhesion coefficient of the tractor, K is the temperature compensation coefficient, T is the reference value of the surface temperature of the tyre, T is the surface temperature of the tyre during the test.

8. The method of testing the dry adhesion coefficient of a vehicle tire according to claim 1, characterized in that, The method comprises the following steps: acquiring the surface roughness of the road surface on the driving path of the tractor tire; determining a correction coefficient according to the static adhesion coefficient of the tractor, the standard dynamic adhesion coefficient of the tractor and the surface roughness; and The traction vehicle drives on the effective test section at the first output power, and the real-time roughness of the road on the driving path of the traction vehicle is acquired according to a preset sampling rate ; real-time road roughness standard dynamic friction coefficient of the towing vehicle one-to-one correspondence a real-time roughness of the road surface a static coefficient of adhesion of the towing vehicle a standard dynamic coefficient of adhesion a correction coefficient K is calculated Establishing real-time roughness correspondence table with the correction coefficient K and stores it.

9. The method for testing the adhesion coefficient on dry ground of motor vehicle tyres according to claim 8, characterised in that, said real-time roughness of the road surface , said static coefficient of adhesion of the tractor , and said standard dynamic coefficient of adhesion a correction factor K is calculated, wherein: The calculation formula of the correction coefficient K is: ; wherein: is the real-time roughness of the road surface on the travel path, is the reference roughness, is the static adhesion coefficient of the towing vehicle, is the standard dynamic adhesion coefficient of the towing vehicle.

10. The method of testing the dry adhesion coefficient of a vehicle tire according to claim 8, characterized in that, The method comprises the following steps: calculating the dynamic adhesion coefficient of the tire to be tested according to the longitudinal force and the lateral force received by the trailer; correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested to obtain the standard dynamic adhesion coefficient of the tire to be tested; correcting the standard dynamic adhesion coefficient of the tire to be tested by using the correction coefficient and outputting the test result. Acquiring real-time longitudinal forces of a trailer , real-time lateral forces , and real-time vertical loads , and calculating dynamic adhesion coefficients of several tires to be tested The method comprises the following steps: calculating the dynamic adhesion coefficient of the tire to be tested according to the longitudinal force and the lateral force received by the trailer; correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested to obtain the standard dynamic adhesion coefficient of the tire to be tested; correcting the standard dynamic adhesion coefficient of the tire to be tested by using the correction coefficient and outputting the test result. The method comprises the following steps: calculating the dynamic adhesion coefficient of the tire to be tested according to the longitudinal force and the lateral force received by the trailer; correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested to obtain the standard dynamic adhesion coefficient of the tire to be tested; correcting the standard dynamic adhesion coefficient of the tire to be tested by using the correction coefficient and outputting the test result. The method comprises the following steps: calculating the dynamic adhesion coefficient of the tire to be tested according to the longitudinal force and the lateral force received by the trailer; correcting the dynamic adhesion coefficient of the tire to be tested according to the speed of the trailer and the surface temperature of the tire to be tested to obtain the standard dynamic adhesion coefficient of the tire to be tested; correcting the standard dynamic adhesion coefficient of the tire to be tested by using the correction coefficient and outputting the test result.

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