阅读说明：本技术 一种扭矩分配方法、装置及系统 (Torque distribution method, device and system ) 是由 官文彬 文增友 牛珍吉 姜博 张进 于 2021-09-18 设计创作，主要内容包括：本申请公开了一种扭矩分配方法、装置及系统,用以降低车辆的操控难度,提升车辆行驶的安全性。所述方法包括：当车辆在目标路面行驶时,获取车辆的预设参数；根据所述预设参数确定所述车辆的前轮和后轮是否存在打滑情况；当所述车辆的前轮和/或后轮存在打滑情况时,根据车辆前后轮的打滑率对所述前后轮的扭矩进行调整,其中,前后轮当前打滑率和所分配的扭矩负相关。采用本申请所提供的方案,降低了车辆的操控难度,提升了车辆行驶的安全性。(The application discloses a torque distribution method, a torque distribution device and a torque distribution system, which are used for reducing the control difficulty of a vehicle and improving the driving safety of the vehicle. The method comprises the following steps: when a vehicle runs on a target road surface, acquiring preset parameters of the vehicle; determining whether the front wheels and the rear wheels of the vehicle have slipping conditions according to the preset parameters; when the front wheels and/or the rear wheels of the vehicle have a slip condition, adjusting the torques of the front wheels and the rear wheels according to the slip rates of the front wheels and the rear wheels of the vehicle, wherein the current slip rates of the front wheels and the rear wheels are inversely related to the distributed torques. By adopting the scheme provided by the application, the control difficulty of the vehicle is reduced, and the driving safety of the vehicle is improved.)

1. A method of torque distribution, comprising:

when a vehicle runs on a target road surface, acquiring preset parameters of the vehicle;

determining whether the front wheels and the rear wheels of the vehicle have slipping conditions according to the preset parameters;

when the front wheels and/or the rear wheels of the vehicle have a slip condition, adjusting the torques of the front wheels and the rear wheels according to the slip rates of the front wheels and the rear wheels of the vehicle, wherein the current slip rates of the front wheels and the rear wheels are inversely related to the distributed torques.

2. The method of claim 1, wherein the method further comprises:

determining the slip rate of the front and rear wheels of the vehicle according to the following formula:

η＝(N-V/7.2πr)/N；

wherein: n is the rotating speed of the motor, and the unit is rotation/second; v is the distance traveled by the vehicle per unit time; r is the tire radius; eta is the slip rate.

3. The method of claim 2, wherein η comprises η 1 and η 2, wherein η 1 is a front wheel slip ratio and η 2 is a rear wheel slip ratio, and wherein determining whether there is slip in the front and rear wheels of the vehicle based on the predetermined parameters comprises:

comparing η 1 to a first threshold and η 2 to a second threshold;

when η 1 is less than a first threshold and η 2 is less than a second threshold, determining that there is no front wheel slip and there is no rear wheel slip;

when eta 1 is larger than a first threshold value and eta 2 is smaller than a second threshold value, determining that the front wheels slip and the rear wheels do not slip;

when eta 1 is smaller than a first threshold value and eta 2 is larger than a second threshold value, determining that the front wheels do not slip and the rear wheels slip;

when η 1 is greater than the first threshold and η 2 is greater than the second threshold, it is determined that both the front and rear wheels are slipping.

4. The method of claim 1, wherein adjusting the torque of the front and rear wheels of the vehicle based on the slip ratio of the front and rear wheels comprises:

when the front wheel slips and the rear wheel does not slip, the torque distribution coefficient of the front wheel is corrected according to the following formula:

β1＝Ra1*(1-η1)；

β2＝1-β1；

wherein β 1 is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; beta 2 is a rear axle torque distribution coefficient adaptively adjusted according to beta 1; eta 1 is the front wheel slip ratio;

or

When the rear wheels slip and the front wheels do not slip, the torque distribution coefficient of the front wheels is corrected according to the following formula:

β2’＝Ra2*(1-η2)

β1’＝1-β2’

wherein β 2' is the corrected rear axle torque distribution coefficient; beta 1 'is a front axle torque distribution coefficient adaptively adjusted according to beta 2'; ra2 is the economic distribution coefficient of the rear axle; eta 2 is the rear wheel slip ratio.

5. The method of claim 1, wherein adjusting the torque of the front and rear wheels of the vehicle based on the slip ratio of the front and rear wheels comprises:

when both the front and rear wheels slip and at least one of η 1 and η 2 has a value other than 1, the torque distribution coefficient of the front and rear wheels is corrected according to the following formula:

β1”＝Ra1*(1-η1)

β2”＝Ra2*(1-η2)

wherein, β 1 "is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; ra2 is the economic distribution coefficient of the rear axle; beta 2' is the corrected rear axle torque distribution coefficient; eta 1 is the front wheel slip ratio; eta 2 is the rear wheel slip ratio;

or

When the front and rear wheels do not slip, torque is distributed to the front and rear axles by an economic distribution coefficient.

6. The method of claim 1, wherein the method further comprises:

determining the current output power of an engine of the vehicle during the running process of the vehicle;

determining the theoretical speed of the vehicle according to the output power;

and when the difference value between the current vehicle speed of the vehicle and the theoretical vehicle speed is larger than a preset difference value, determining that the vehicle runs on a target road surface.

7. The method of claim 5, wherein the method further comprises:

and when the front wheel and the rear wheel both slip and the values of eta 1 and eta 2 are both 1, executing the parking braking operation of the vehicle and sending out the information for reminding that the vehicle is trapped.

8. The method of claim 1, wherein the obtaining preset parameters of the vehicle comprises:

acquiring at least one of the following parameters:

motor speed, distance traveled by the vehicle per unit time, front wheel radius, and rear wheel radius.

9. A torque distribution device, comprising:

the acquisition module is used for acquiring preset parameters of the vehicle when the vehicle runs on a target road surface;

the determining module is used for determining whether the front wheels and the rear wheels of the vehicle have a slipping condition according to the preset parameters;

and the adjusting module is used for adjusting the torques of the front wheels and the rear wheels according to the slip rates of the front wheels and the rear wheels of the vehicle when the front wheels and/or the rear wheels of the vehicle slip, wherein the current slip rates of the front wheels and the rear wheels are inversely related to the distributed torques.

10. A torque distribution system, comprising:

at least one processor; and the number of the first and second groups,

a memory communicatively coupled to the at least one processor; wherein the content of the first and second substances,

the memory stores instructions executable by the one processor to implement the torque distribution method of any one of claims 1-8.

Technical Field

The present disclosure relates to the field of vehicle control technologies, and in particular, to a torque distribution method, device and system.

Background

Four-wheel drive means that the vehicle keeps a four-wheel drive mode all the time during running, the output torque of an engine is distributed to front wheels and rear wheels in a fixed proportion, and compared with two-wheel drive, the four-wheel drive mode can have better off-road and handling performance at any time.

The vehicle is gone on the road surface that frictional force is less such as icy road, muddy road, can take place certain hydroplaning phenomenon, and even when certain wheel is controlled, if continue to drive the vehicle according to the moment of torsion of fixed proportion, the tire that is in hydroplaning or is controlled the state continues to distribute fixed moment of torsion and can make the control degree of difficulty increase of vehicle, consequently, need to provide a moment of torsion distribution scheme to reduce the control degree of difficulty of vehicle, promote the security that the vehicle travel.

Disclosure of Invention

The application provides a torque distribution method, a torque distribution device and a torque distribution system, which are used for reducing the control difficulty of a vehicle and improving the driving safety of the vehicle.

The present application provides a torque distribution method comprising:

when a vehicle runs on a target road surface, acquiring preset parameters of the vehicle;

determining whether the front wheels and the rear wheels of the vehicle have slipping conditions according to the preset parameters;

when the front wheels and/or the rear wheels of the vehicle have a slip condition, adjusting the torques of the front wheels and the rear wheels according to the slip rates of the front wheels and the rear wheels of the vehicle, wherein the current slip rates of the front wheels and the rear wheels are inversely related to the distributed torques.

The beneficial effect of this application lies in: when the front wheels and/or the rear wheels of the vehicle slip, the torques of the front wheels and the rear wheels are adjusted according to the slip rates of the front wheels and the rear wheels of the vehicle, so that the torques of the wheels can be adaptively adjusted according to whether the wheels of the vehicle slip or not, and the current slip rates of the front wheels and the rear wheels are inversely related to the distributed torques, namely, the greater the slip rate is, the smaller the distributed torques are, thereby reducing the control difficulty of the vehicle and improving the running safety of the vehicle.

In one embodiment, the method further comprises:

determining the slip rate of the front and rear wheels of the vehicle according to the following formula:

η＝(N-V/7.2πr)/N；

wherein: n is the rotating speed of the motor, and the unit is rotation/second; v is the distance traveled by the vehicle per unit time; r is the tire radius; eta is the slip rate.

In one embodiment, the η includes η 1 and η 2, the η 1 is a front wheel slip ratio, the η 2 is a rear wheel slip ratio, and the determining whether there is a slip condition between the front wheel and the rear wheel of the vehicle according to the preset parameters includes:

comparing η 1 to a first threshold and η 2 to a second threshold;

when η 1 is less than a first threshold and η 2 is less than a second threshold, determining that there is no front wheel slip and there is no rear wheel slip;

when eta 1 is larger than a first threshold value and eta 2 is smaller than a second threshold value, determining that the front wheels slip and the rear wheels do not slip;

when eta 1 is smaller than a first threshold value and eta 2 is larger than a second threshold value, determining that the front wheels do not slip and the rear wheels slip;

when η 1 is greater than the first threshold and η 2 is greater than the second threshold, it is determined that both the front and rear wheels are slipping.

In one embodiment, adjusting the torque of the front and rear wheels of the vehicle based on the slip rates of the front and rear wheels comprises:

when the front wheel slips and the rear wheel does not slip, the torque distribution coefficient of the front wheel is corrected according to the following formula:

β1＝Ra1*(1-η1)；

β2＝1-β1；

wherein β 1 is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; beta 2 is a rear axle torque distribution coefficient adaptively adjusted according to beta 1; eta 1 is the front wheel slip ratio;

or

When the rear wheels slip and the front wheels do not slip, the torque distribution coefficient of the front wheels is corrected according to the following formula:

β2’＝Ra2*(1-η2)

β1’＝1-β2’

wherein β 2' is the corrected rear axle torque distribution coefficient; beta 1 'is a front axle torque distribution coefficient adaptively adjusted according to beta 2'; ra2 is the economic distribution coefficient of the rear axle; eta 2 is the rear wheel slip ratio.

The beneficial effect of this embodiment lies in: the torque distribution coefficient corresponding to the slipping wheel is reduced, and the reduced torque distribution coefficient is distributed to the non-slipping wheel, so that the conversion rate of power is improved on the basis of improving the driving safety.

In one embodiment, adjusting the torque of the front and rear wheels of the vehicle based on the slip rates of the front and rear wheels comprises:

when both the front and rear wheels slip, the torque distribution coefficients of the front and rear wheels are corrected according to the following formula:

β1”＝Ra1*(1-η1)

β2”＝Ra2*(1-η2)

wherein, β 1 "is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; ra2 is the economic distribution coefficient of the rear axle; beta 2' is the corrected rear axle torque distribution coefficient; eta 1 is the front wheel slip ratio; eta 2 is the rear wheel slip ratio;

or

When the front and rear wheels do not slip, torque is distributed to the front and rear axles by an economic distribution coefficient.

In one embodiment, the method further comprises:

determining the current output power of an engine of the vehicle during the running process of the vehicle;

determining the theoretical speed of the vehicle according to the output power;

and when the difference value between the current vehicle speed of the vehicle and the theoretical vehicle speed is larger than a preset difference value, determining that the vehicle runs on a target road surface.

The beneficial effect of this embodiment lies in: the method provides a recognition mode about the target road surface, so that the vehicle can only execute torque dynamic adjustment operation on the target road surface, and the consumption of vehicle-mounted computing resources is saved.

In one embodiment, the method further comprises:

and when the front wheel and the rear wheel both slip and the values of eta 1 and eta 2 are both 1, executing the parking braking operation of the vehicle and sending out the information for reminding that the vehicle is trapped.

In one embodiment, the obtaining preset parameters of the vehicle includes:

acquiring at least one of the following parameters:

motor speed, distance traveled by the vehicle per unit time, front wheel radius, and rear wheel radius.

The present application further provides a torque distribution device comprising:

the acquisition module is used for acquiring preset parameters of the vehicle when the vehicle runs on a target road surface;

the determining module is used for determining whether the front wheels and the rear wheels of the vehicle have a slipping condition according to the preset parameters;

and the adjusting module is used for adjusting the torques of the front wheels and the rear wheels according to the slip rates of the front wheels and the rear wheels of the vehicle when the front wheels and/or the rear wheels of the vehicle slip, wherein the current slip rates of the front wheels and the rear wheels are inversely related to the distributed torques.

In one embodiment, the apparatus further comprises:

a slip rate determination module for determining slip rates of front and rear wheels of a vehicle according to the following formula:

η＝(N-V/7.2πr)/N；

wherein: n is the rotating speed of the motor, and the unit is rotation/second; v is the distance traveled by the vehicle per unit time; r is the tire radius; eta is the slip rate.

In one embodiment, the η includes η 1 and η 2, the η 1 is a front wheel slip ratio, and the η 2 is a rear wheel slip ratio, and the determining module includes:

a comparison submodule for comparing η 1 with a first threshold and η 2 with a second threshold;

a first determination submodule for determining that there is no slip of the front wheels and there is no slip of the rear wheels when η 1 is smaller than a first threshold value and η 2 is smaller than a second threshold value;

a second determination submodule for determining that the front wheels are slipping and the rear wheels are not slipping when η 1 is greater than the first threshold and η 2 is less than a second threshold;

a third determining submodule, configured to determine that the front wheels do not slip and the rear wheels slip when η 1 is smaller than the first threshold and η 2 is larger than the second threshold;

a fourth determination submodule for determining that both the front and rear wheels are slipping when η 1 is greater than the first threshold value and η 2 is greater than the second threshold value.

In one embodiment, the adjustment module includes: a first modifier submodule or a second modifier submodule;

the first correction submodule is used for correcting the torque distribution coefficient of the front wheel according to the following formula when the front wheel slips and the rear wheel does not slip:

β1＝Ra1*(1-η1)；

β2＝1-β1；

wherein β 1 is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; beta 2 is a rear axle torque distribution coefficient adaptively adjusted according to beta 1; eta 1 is the front wheel slip ratio;

the second correction submodule is used for correcting the torque distribution coefficient of the front wheel according to the following formula when the rear wheel slips and the front wheel does not slip:

β2’＝Ra2*(1-η2)

β1’＝1-β2’

wherein β 2' is the corrected rear axle torque distribution coefficient; beta 1 'is a front axle torque distribution coefficient adaptively adjusted according to beta 2'; ra2 is the economic distribution coefficient of the rear axle; eta 2 is the rear wheel slip ratio.

In one embodiment, the adjustment module includes: a third correction submodule or torque distribution submodule;

the third correction submodule is configured to correct the torque distribution coefficient of the front and rear wheels according to the following equation when both the front and rear wheels slip and at least one of η 1 and η 2 has a value other than 1:

β1”＝Ra1*(1-η1)

β2”＝Ra2*(1-η2)

wherein, β 1 "is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; ra2 is the economic distribution coefficient of the rear axle; beta 2' is the corrected rear axle torque distribution coefficient; eta 1 is the front wheel slip ratio; eta 2 is the rear wheel slip ratio;

and the torque distribution submodule is used for distributing the torque for the front axle and the rear axle by using an economic distribution coefficient when the front wheel and the rear wheel do not slip.

In one embodiment, the apparatus further comprises:

the output power determination module is used for determining the current output power of an engine of the vehicle during the running process of the vehicle;

the vehicle speed determining module is used for determining the theoretical vehicle speed of the vehicle according to the output power;

and the running position determining module is used for determining that the vehicle runs on a target road surface when the difference value between the current vehicle speed of the vehicle and the theoretical vehicle speed is larger than a preset difference value.

In one embodiment, the apparatus further comprises:

and the braking module is used for executing parking braking operation of the vehicle and sending out prompting information that the vehicle is trapped when the front wheel and the rear wheel both slip and the values of eta 1 and eta 2 are both 1.

In one embodiment, the obtaining preset parameters of the vehicle includes:

acquiring at least one of the following parameters:

motor speed, distance traveled by the vehicle per unit time, front wheel radius, and rear wheel radius.

The present application further provides a torque distribution system comprising:

at least one processor; and the number of the first and second groups,

a memory communicatively coupled to the at least one processor; wherein the content of the first and second substances,

the memory stores instructions executable by the one processor to implement the torque distribution method of any of the above embodiments.

The present application further provides a computer-readable storage medium, wherein when the instructions in the storage medium are executed by a processor corresponding to the torque distribution system, the torque distribution system is enabled to implement the torque distribution method described in any of the above embodiments.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the application. The objectives and other advantages of the application may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

The technical solution of the present application is further described in detail by the accompanying drawings and examples.

Drawings

The accompanying drawings are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiment(s) of the application and together with the description serve to explain the application and not limit the application. In the drawings:

FIG. 1 is a flow chart of a torque distribution method in an embodiment of the present application;

FIG. 2 is a flow chart of a method of torque distribution in another embodiment of the present application;

FIG. 3 is a block diagram of a torque distribution device according to an embodiment of the present application;

FIG. 4 is a flow chart of a method of torque distribution in a general embodiment of the present application;

fig. 5 is a schematic diagram of a hardware structure of a torque distribution system according to the present application.

Detailed Description

The preferred embodiments of the present application will be described in conjunction with the accompanying drawings, and it will be understood that they are described herein only to illustrate and explain the present application and not to limit the present application.

FIG. 1 is a flow chart of a torque distribution method in one embodiment of the present application, which may be implemented as the following steps S11-S13:

in step S11, when the vehicle is running on the target road surface, acquiring preset parameters of the vehicle;

in step S12, determining whether there is a slip condition between the front and rear wheels of the vehicle according to the preset parameters;

in step S13, when there is a slip condition on the front and/or rear wheels of the vehicle, the torques of the front and rear wheels are adjusted according to the slip rates of the front and rear wheels of the vehicle, wherein the current slip rates of the front and rear wheels are inversely related to the distributed torques.

In the embodiment, when a vehicle runs on a target road surface, preset parameters of the vehicle are obtained; the target road surface is a road surface with small friction force, such as an icy road surface and a muddy road surface, and the vehicle can be determined to run on the target road surface in the following way:

in a first mode

Determining the current output power of an engine of the vehicle during the running process of the vehicle;

determining the theoretical speed of the vehicle according to the output power;

and when the difference value between the current vehicle speed of the vehicle and the theoretical vehicle speed is larger than a preset difference value, determining that the vehicle runs on a target road surface.

For example, the preset difference is 10 km/h, and during the running of the vehicle, it is determined that the theoretical vehicle speed corresponding to the current output power of the engine is 100 km/h, but the current actual vehicle speed of the vehicle is 70 km/h, that is, the difference between the current vehicle speed of the vehicle and the theoretical vehicle speed is greater than the preset difference, which indicates that the vehicle runs on a road surface with low friction, such as an icy road surface and a muddy road surface.

Mode two

Acquiring the position of a vehicle in the running process of the vehicle;

determining a weather condition corresponding to the current position;

and when the weather conditions meet specific conditions, determining that the vehicle runs on a target road surface.

For example, during the running process of the vehicle, it is determined that the vehicle is located on a road of city b, and the current weather condition of the road of city b is rainy or snowy weather, and the temperature is below zero, which indicates that the vehicle runs on a road with low friction, such as an icy road and a muddy road.

When the vehicle is determined to run on the target road surface, preset parameters of the vehicle are obtained, and specifically, the motor rotating speed of the vehicle, the distance traveled by the vehicle in unit time, the radius of the front wheel and the radius of the rear wheel can be obtained.

Determining whether the front wheels and the rear wheels of the vehicle have slipping conditions according to the preset parameters; specifically, the slip rates of the front and rear wheels of the vehicle are determined according to the following formula:

η ═ N-V/7.2 π r/N; formula (1)

Wherein: n is the rotating speed of the motor, and the unit is rotation/second; v is the distance traveled by the vehicle per unit time, for example, V may be the distance traveled by the vehicle for a time of 1 second; r is the tire radius; eta is the slip rate.

Eta comprises eta 1 and eta 2, wherein eta 1 is the front wheel slip rate, eta 2 is the rear wheel slip rate, and eta 1 is compared with a first threshold value and eta 2 is compared with a second threshold value when the wheel is judged to have the slip condition; when η 1 is less than a first threshold and η 2 is less than a second threshold, determining that there is no front wheel slip and there is no rear wheel slip; when eta 1 is larger than a first threshold value and eta 2 is smaller than a second threshold value, determining that the front wheels slip and the rear wheels do not slip; when eta 1 is smaller than a first threshold value and eta 2 is larger than a second threshold value, determining that the front wheels do not slip and the rear wheels slip; when η 1 is greater than the first threshold and η 2 is greater than the second threshold, it is determined that both the front and rear wheels are slipping.

When the front wheels and/or the rear wheels of the vehicle have a slip condition, adjusting the torques of the front wheels and the rear wheels according to the slip rates of the front wheels and the rear wheels of the vehicle, wherein the current slip rates of the front wheels and the rear wheels are inversely related to the distributed torques.

When the torques of the front and rear wheels are adjusted according to the slip ratios of the front and rear wheels of the vehicle, four situations exist: 1. the front wheel and the rear wheel do not slip; 2. the front wheels slip, the rear wheels do not slip; 3. the rear wheels slip, the front wheels do not slip; 4. both the front and rear wheels slip.

As shown in fig. 4, the adjustment is made according to the front and rear wheel slip ratio as follows:

in condition 1, when none of the front rear wheels slips, it is described that the vehicle is currently running on the target road surface, but the current frictional force of the target road surface is still large, and for example, the vehicle is snowing immediately when the target road surface is determined. Or whether the vehicle is judged to be misjudged when the vehicle runs on the target road surface or not is explained, namely, the vehicle does not run on the target road surface currently.

And 2, when the front wheel slips and the rear wheel does not slip, correcting the torque distribution coefficient of the front wheel according to the following formula:

β1＝Ra1*(1-η1)；

β2＝1-β1；

wherein β 1 is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; beta 2 is a rear axle torque distribution coefficient adaptively adjusted according to beta 1; eta 1 is the front wheel slip ratio;

condition 3, when the rear wheels slip and the front wheels do not slip, the torque distribution coefficient of the front wheels is corrected according to the following formula:

β2’＝Ra2*(1-η2)

β1’＝1-β2’

wherein β 2' is the corrected rear axle torque distribution coefficient; beta 1 'is a front axle torque distribution coefficient adaptively adjusted according to beta 2'; ra2 is the economic distribution coefficient of the rear axle; eta 2 is the rear wheel slip ratio.

And 4, when the front and rear wheels are all slipped, correcting the torque distribution coefficients of the front and rear wheels according to the following formula:

β1”＝Ra1*(1-η1)

β2”＝Ra2*(1-η2)

wherein, β 1 "is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; ra2 is the economic distribution coefficient of the rear axle; beta 2' is the corrected rear axle torque distribution coefficient; eta 1 is the front wheel slip ratio; eta 2 is the rear wheel slip ratio.

It should be noted that, in this embodiment, when the vehicle does not run on the target road surface, the preset parameters of the vehicle may not be acquired, so that the consumption of the computing resources of the entire vehicle is reduced. In this case, the torque distribution coefficient is an economic torque distribution coefficient, i.e. torque distribution is performed according to the minimum fuel consumption and/or electricity consumption principle.

The beneficial effect of this application lies in: when the front wheels and/or the rear wheels of the vehicle slip, the torques of the front wheels and the rear wheels are adjusted according to the slip rates of the front wheels and the rear wheels of the vehicle, so that the torques of the wheels can be adaptively adjusted according to whether the wheels of the vehicle slip or not, and the current slip rates of the front wheels and the rear wheels are inversely related to the distributed torques, namely, the greater the slip rate is, the smaller the distributed torques are, thereby reducing the control difficulty of the vehicle and improving the running safety of the vehicle.

In one embodiment, the method may also be implemented as the steps of:

determining the slip rate of the front and rear wheels of the vehicle according to the following formula:

η＝(N-V/7.2πr)/N；

wherein: n is the rotating speed of the motor, and the unit is rotation/second; v is the distance traveled by the vehicle per unit time; r is the tire radius; eta is the slip rate.

In one embodiment, the η includes η 1 and η 2, the η 1 is the front wheel slip ratio, the η 2 is the rear wheel slip ratio, as shown in fig. 2, the above step S12 may be implemented as the following steps a1-a 5:

in step a1, η 1 is compared with a first threshold and η 2 is compared with a second threshold;

in step a2, when η 1 is less than the first threshold and η 2 is less than the second threshold, it is determined that there is no slip of the front wheels and there is no slip of the rear wheels;

in step a3, when η 1 is greater than a first threshold and η 2 is less than a second threshold, determining that the front wheels are slipping and the rear wheels are not slipping;

in step a4, when η 1 is less than a first threshold and η 2 is greater than a second threshold, it is determined that the front wheels are not slipping and the rear wheels are slipping;

in step a5, when η 1 is greater than the first threshold value and η 2 is greater than the second threshold value, it is determined that both the front and rear wheels are slipping.

In this embodiment, η 1 is compared with a first threshold, and η 2 is compared with a second threshold; determining the slipping condition of the wheels according to the comparison result, specifically, when eta 1 is smaller than a first threshold value and eta 2 is smaller than a second threshold value, determining that no front wheel slips and no rear wheel slips; when eta 1 is larger than a first threshold value and eta 2 is smaller than a second threshold value, determining that the front wheels slip and the rear wheels do not slip; when eta 1 is smaller than a first threshold value and eta 2 is larger than a second threshold value, determining that the front wheels do not slip and the rear wheels slip; when η 1 is greater than the first threshold and η 2 is greater than the second threshold, it is determined that both the front and rear wheels are slipping.

The first threshold and the second threshold may be 0. In addition, some road surfaces may cause the vehicle to slightly slip, but may not increase the difficulty of driving the vehicle, and therefore, the first threshold value and the second threshold value may be slip values that are greater than 0, but may not increase the difficulty of driving the vehicle. The first threshold and the second threshold may be the same.

In one embodiment, the adjustment of the torques of the front and rear wheels according to the slip rates of the front and rear wheels of the vehicle in the above step S13 may be implemented as the following step B1 or B2:

in step B1, when the front wheels slip and the rear wheels do not slip, the torque distribution coefficient of the front wheels is corrected according to the following formula:

β 1 ═ Ra1 (1- η 1); formula (2)

β 2 ═ 1- β 1; formula (3)

Wherein β 1 is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; beta 2 is a rear axle torque distribution coefficient adaptively adjusted according to beta 1; eta 1 is the front wheel slip ratio;

in step B2, when the rear wheels slip and the front wheels do not slip, the torque distribution coefficient of the front wheels is corrected according to the following formula:

β 2' ═ Ra2 (1-. eta.2) formula (4)

β 1 ═ 1 β 2' equation (5)

Wherein β 2' is the corrected rear axle torque distribution coefficient; beta 1 'is a front axle torque distribution coefficient adaptively adjusted according to beta 2'; ra2 is the economic distribution coefficient of the rear axle; eta 2 is the rear wheel slip ratio.

The beneficial effect of this embodiment lies in: the torque distribution coefficient corresponding to the slipping wheel is reduced, and the reduced torque distribution coefficient is distributed to the non-slipping wheel, so that the conversion rate of power is improved on the basis of improving the driving safety.

In one embodiment, the adjusting of the torques of the front and rear wheels according to the slip rates of the front and rear wheels of the vehicle in the above step S13 may be further implemented as the following step C1 or C2:

in step C1, when both the front and rear wheels slip, the torque distribution coefficient of the front and rear wheels is corrected according to the following equation:

β 1 ═ Ra1 (1-. eta.1) formula (6)

β 2 ═ Ra2 (1- η 2) formula (7)

Wherein, β 1 "is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; ra2 is the economic distribution coefficient of the rear axle; beta 2' is the corrected rear axle torque distribution coefficient; eta 1 is the front wheel slip ratio; eta 2 is the rear wheel slip ratio;

in step C2, when none of the front and rear wheels is slipping, torque is distributed to the front and rear axles at the economic distribution factor.

That is, in step C2, the front axle torque distribution coefficient is Ra1 and the rear axle torque distribution coefficient is Ra 2.

It is to be understood that η 1 and η 2 referred to in the above equations (2), (3), (4), (5), (6) and (7) are equivalent to η in the above equation (1) only for the purpose of distinguishing the front and rear wheels, and therefore, are distinguished by η 1 and η 2.

In addition, it can be understood that when the slip rate of the front wheels is close to 100%, it indicates that the front wheels are sunk into mud pits or in a suspended state, and at this time, the torque is no longer distributed to the front wheels, that is, the torque distributed to the front wheels is 0, and the torque distributed to the rear wheels is 1-0; similarly, when the slip rate of the rear wheels is close to 100%, the rear wheels are sunk into mud pits or in a suspended state, and at the moment, the torque is not distributed to the rear wheels, namely the torque distributed to the rear wheels is 0, and the torque distributed to the front wheels is 1-0 ═ 1.

In one embodiment, as shown in FIG. 2, the method may also be implemented as the following steps S21-S23:

in step S21, during running of the vehicle, determining a current output power of an engine of the vehicle;

in step S22, determining a theoretical vehicle speed of the vehicle based on the output power;

in step S23, when the difference between the current vehicle speed and the theoretical vehicle speed of the vehicle is greater than a preset difference, it is determined that the vehicle is traveling on a target road surface.

For example, the preset difference is 10 km/h, and in the driving process of the vehicle, it is determined that the theoretical vehicle speed corresponding to the current output power of the engine is 100 km/h, but the current actual vehicle speed of the vehicle is 70 km/h, that is, the difference between the current vehicle speed of the vehicle and the theoretical vehicle speed is greater than the preset difference, which indicates that the vehicle is driven on a road with low friction, such as an icy road and a muddy road.

The beneficial effect of this embodiment lies in: an identification manner about the target road surface is provided, so that the vehicle can only execute the torque dynamic adjustment operation on the target road surface, and the consumption of vehicle-mounted computing resources is saved.

Or

Acquiring the position of a vehicle in the running process of the vehicle;

determining a weather condition corresponding to the current position;

and when the weather conditions meet specific conditions, determining that the vehicle runs on a target road surface.

For example, in the driving process of the vehicle, it is determined that the vehicle is located on a road of city a and b, the current weather condition of the road of city a and b is rainy and snowy weather, and the temperature is below zero, which indicates that the vehicle is driven on a road with low friction, such as an icy road and a muddy road.

In one embodiment, the method may also be implemented as the steps of:

and when the front wheel and the rear wheel both slip and the values of eta 1 and eta 2 are both 1, executing the parking braking operation of the vehicle and sending out the information for reminding that the vehicle is trapped.

Specifically, when the current rear wheels all slip and the values of η 1 and η 2 are both 1, it is indicated that the vehicle is in a controlled state, at this time, the vehicle enters a release mode, torque adjustment is no longer performed according to the above formula, at this time, parking brake operation of the vehicle can be performed, and a notification message that the vehicle is trapped is sent.

In this embodiment, when the front and rear wheels all slip and the values of η 1 and η 2 are both 1, it is considered that the vehicle cannot escape even if torque continues to be distributed, and at this time, the parking brake operation of the vehicle is performed in order to avoid the continued waste of fuel resources or electric resources of the vehicle. In addition, a prompting message for vehicle trapping can be sent to prompt a driver that the vehicle is trapped and needs to be released by means of external force.

In addition, when the front and rear wheels are slipping and the values of η 1 and η 2 are both 1, the throttle size and the motor displacement can be adjusted to the maximum. Thereby improving the rotating speed of the wheel and increasing the success rate of getting rid of difficulties.

It should be noted that, when the front and rear wheels are slipping and both values of η 1 and η 2 are 1, if the vehicle is equipped with the auxiliary device for escaping from the vehicle, the auxiliary device for escaping from the vehicle is activated. The auxiliary device for getting rid of the trouble can be a hydraulic lifting device arranged on the vehicle, and can lift the vehicle to other areas so as to get rid of the trouble.

In one embodiment, the obtaining preset parameters of the vehicle includes:

acquiring at least one of the following parameters:

motor speed, distance traveled by the vehicle per unit time, front wheel radius, and rear wheel radius.

FIG. 3 is a block diagram of a torque distribution apparatus according to an embodiment of the present application, which may include the following modules:

the acquisition module 31 is used for acquiring preset parameters of the vehicle when the vehicle runs on a target road surface;

the determining module 32 is used for determining whether the front wheels and the rear wheels of the vehicle have a slip condition according to the preset parameters;

and an adjusting module 33, configured to adjust the torques of the front and rear wheels according to the slip rates of the front and rear wheels of the vehicle when there is a slip condition on the front and/or rear wheels of the vehicle, where the current slip rates of the front and rear wheels are inversely related to the allocated torques.

In one embodiment, the apparatus further comprises:

a slip rate determination module for determining slip rates of front and rear wheels of a vehicle according to the following formula:

η＝(N-V/7.2πr)/N；

wherein: n is the rotating speed of the motor, and the unit is rotation/second; v is the distance traveled by the vehicle per unit time; r is the tire radius; eta is the slip rate.

In one embodiment, the η includes η 1 and η 2, the η 1 is a front wheel slip ratio, and the η 2 is a rear wheel slip ratio, and the determining module includes:

a comparison submodule for comparing η 1 with a first threshold and η 2 with a second threshold;

a first determination submodule for determining that there is no slip of the front wheels and there is no slip of the rear wheels when η 1 is smaller than a first threshold value and η 2 is smaller than a second threshold value;

a second determination submodule for determining that the front wheels are slipping and the rear wheels are not slipping when η 1 is greater than the first threshold and η 2 is less than a second threshold;

a third determining submodule, configured to determine that the front wheels do not slip and the rear wheels slip when η 1 is smaller than the first threshold and η 2 is larger than the second threshold;

a fourth determination submodule for determining that both the front and rear wheels are slipping when η 1 is greater than the first threshold value and η 2 is greater than the second threshold value.

In one embodiment, the adjustment module includes: a first modifier submodule or a second modifier submodule;

the first correction submodule is used for correcting the torque distribution coefficient of the front wheel according to the following formula when the front wheel slips and the rear wheel does not slip:

β1＝Ra1*(1-η1)；

β2＝1-β1；

wherein β 1 is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; beta 2 is a rear axle torque distribution coefficient adaptively adjusted according to beta 1; eta 1 is the front wheel slip ratio;

the second correction submodule is used for correcting the torque distribution coefficient of the front wheel according to the following formula when the rear wheel slips and the front wheel does not slip:

β2’＝Ra2*(1-η2)

β1’＝1-β2’

wherein β 2' is the corrected rear axle torque distribution coefficient; beta 1 'is a front axle torque distribution coefficient adaptively adjusted according to beta 2'; ra2 is the economic distribution coefficient of the rear axle; eta 2 is the rear wheel slip ratio.

In one embodiment, the adjustment module includes: a third correction submodule or torque distribution submodule;

the third correction submodule is configured to correct the torque distribution coefficient of the front and rear wheels according to the following equation when both the front and rear wheels slip and at least one of η 1 and η 2 has a value other than 1:

β1”＝Ra1*(1-η1)

β2”＝Ra2*(1-η2)

wherein, β 1 "is the corrected front axle torque distribution coefficient; ra1 is the front axle economic share coefficient; ra2 is the economic distribution coefficient of the rear axle; beta 2' is the corrected rear axle torque distribution coefficient; eta 1 is the front wheel slip ratio; eta 2 is the rear wheel slip ratio;

and the torque distribution submodule is used for distributing the torque for the front axle and the rear axle by using an economic distribution coefficient when the front wheel and the rear wheel do not slip.

In one embodiment, the apparatus further comprises:

the output power determination module is used for determining the current output power of an engine of the vehicle during the running process of the vehicle;

the vehicle speed determining module is used for determining the theoretical vehicle speed of the vehicle according to the output power;

and the running position determining module is used for determining that the vehicle runs on a target road surface when the difference value between the current vehicle speed of the vehicle and the theoretical vehicle speed is larger than a preset difference value.

In one embodiment, the apparatus further comprises:

and the braking module is used for executing parking braking operation of the vehicle and sending out prompting information that the vehicle is trapped when the front wheel and the rear wheel both slip and the values of eta 1 and eta 2 are both 1.

In one embodiment, the obtaining preset parameters of the vehicle includes:

acquiring at least one of the following parameters:

motor speed, distance traveled by the vehicle per unit time, front wheel radius, and rear wheel radius.

Fig. 4 is a flowchart of a torque distribution method according to a general embodiment of the present application, as shown in fig. 4, four tires F1 (front left), F2 (front right), R1 (rear left) and R2 (rear right) of a vehicle are respectively monitored in real time, and the slip ratios of the respective tires are respectively calculated according to the above formula (1), wherein after the slip ratios of F1 and F2 are calculated, there may be a deviation in the slip ratios of the two front wheels, and therefore, the front wheel calculates a larger value of the two slip ratios corresponding to the two front wheels as η 1 referred to in the above formulae (2), (3), (4), (5), (6) and (7), and similarly, after the slip ratios of the two rear wheels are calculated, the larger value is taken as η 2 referred to in the above formulae. Then, the torque distribution coefficient is corrected according to the above conditions 1 to 4, that is, the torque of the front and rear wheels is adjusted according to the slip ratios of the front and rear wheels of the vehicle in the above step S13.

Fig. 5 is a schematic diagram of a hardware structure of a torque distribution system according to the present application, including:

at least one processor 520; and the number of the first and second groups,

a memory 504 communicatively coupled to the at least one processor; wherein the content of the first and second substances,

the memory stores instructions executable by the one processor to implement the torque distribution method of any of the above embodiments.

Referring to fig. 5, the torque distribution system 500 may include one or more of the following components: processing component 502, memory 504, power component 506, multimedia component 508, audio component 510, input/output (I/O) interface 512, sensor component 514, and communication component 516.

The processing component 502 generally controls the overall operation of the torque distribution system 500, and the processing component 502 may include one or more processors 520 to execute instructions to perform all or a portion of the steps of the method described above. Further, the processing component 502 can include one or more modules that facilitate interaction between the processing component 502 and other components. For example, the processing component 502 can include a multimedia module to facilitate interaction between the multimedia component 508 and the processing component 502.

The memory 504 is configured to store various types of data to support operation of the torque distribution system 500. Examples of such data include instructions for any application or method operating on torque distribution system 500, such as text, pictures, video, and so forth. The memory 504 may be implemented by any type or combination of volatile or non-volatile memory devices such as Static Random Access Memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic or optical disks.

The power supply component 506 provides power to the various components of the torque distribution system 500. The power components 506 may include a power management system, one or more power sources, and other components associated with generating, managing, and distributing power to the torque distribution system 500.

The multimedia component 508 includes a screen that provides an output interface between the torque distribution system 500 and a user. In some embodiments, the screen may include a Liquid Crystal Display (LCD) and a Touch Panel (TP). If the screen includes a touch panel, the screen may be implemented as a touch screen to receive an input signal from a user. The touch panel includes one or more touch sensors to sense touch, slide, and gestures on the touch panel. The touch sensor may not only sense the boundary of a touch or slide action, but also detect the duration and pressure associated with the touch or slide operation. In some embodiments, the multimedia component 508 may further display some status information corresponding to the vehicle on the touch screen, for example, the above-mentioned reminding information of the vehicle being trapped.

The audio component 510 is configured to output and/or input audio signals. For example, audio assembly 510 includes a Microphone (MIC) configured to receive external audio signals when torque distribution system 500 is in an operating mode, such as a call mode, a recording mode, and a voice recognition mode. The received audio signals may further be stored in the memory 504 or transmitted via the communication component 516. In some embodiments, the audio component 510 further comprises a speaker for outputting an audio signal, for example, by sending an audible signal to alert that the vehicle is trapped.

The I/O interface 512 provides an interface between the processing component 502 and peripheral interface modules, which may be keyboards, click wheels, buttons, etc. These buttons may include, but are not limited to: a home button, a volume button, a start button, and a lock button.

The sensor assembly 514 includes one or more sensors for providing various aspects of state estimation for the torque distribution system 500. For example, the sensor assembly 514 may include, for example, a wheel speed sensor, which may collect the rotational speed of the vehicle to determine whether the vehicle has signs of slip, and cause the processor 520 to calculate a theoretical vehicle speed of the vehicle; a speed sensor may be used to determine a current vehicle speed of the vehicle.

The communication component 516 is configured to enable the torque distribution system 500 to provide wired or wireless communication capabilities with other devices and cloud platforms. The torque distribution system 500 may access wireless networks based on communication standards, such as WiFi, 2G or 3G, or a combination thereof. In an exemplary embodiment, the communication component 516 receives a broadcast signal or broadcast related information from an external broadcast management system via a broadcast channel. In an exemplary embodiment, the communication component 516 further includes a Near Field Communication (NFC) module to facilitate short-range communications. For example, the NFC module may be implemented based on Radio Frequency Identification (RFID) technology, infrared data association (IrDA) technology, Ultra Wideband (UWB) technology, Bluetooth (BT) technology, and other technologies.

In an exemplary embodiment, the torque distribution system 500 may be implemented by one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), controllers, micro-controllers, microprocessors, or other electronic components for performing the charging methods described above.

The present application further provides a computer-readable storage medium, wherein when the instructions in the storage medium are executed by a processor corresponding to the torque distribution system, the torque distribution system is enabled to implement the torque distribution method described in any of the above embodiments.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.