CN118790255B

CN118790255B - Method for starting separated road surface and vehicle

Info

Publication number: CN118790255B
Application number: CN202411280474.6A
Authority: CN
Inventors: 刘宏伟
Original assignee: Zhangjiagang Great Wall Motor Research and Development Co Ltd
Current assignee: Zhangjiagang Great Wall Motor Research and Development Co Ltd
Priority date: 2024-09-13
Filing date: 2024-09-13
Publication date: 2025-01-07
Anticipated expiration: 2044-09-13
Also published as: CN118790255A

Abstract

The present application discloses a starting method and a vehicle on a separated road surface, and belongs to the field of vehicle technology. Through the technical solution provided by the embodiment of the present application, when the target vehicle starts on a separated road surface, a braking force is applied to the wheels of the target vehicle located on a low-attachment road surface (low-attachment side wheels) and the adhesion of the wheels on both sides of the target vehicle (low-attachment side wheels and high-attachment side wheels) is determined. Based on the adhesion and driving force of the wheels on both sides of the target vehicle, the target rear wheel steering angle of the target vehicle is determined, and the target rear wheel steering angle is used to reduce the yaw of the target vehicle when starting. Based on the target rear wheel steering angle and the starting driving distance of the target vehicle, the rear wheels of the target vehicle are controlled to steer, so as to offset the yaw of the target vehicle by the steering of the rear wheels, thereby improving the safety and comfort of the target vehicle when starting.

Description

Method for starting separated road surface and vehicle

Technical Field

The application relates to the technical field of vehicles, in particular to a starting method for separating a road surface and a vehicle in the technical field of vehicles.

Background

The user can face various working conditions when driving the vehicle, and the vehicle needs to be kept stable under different working conditions, so that the vehicle is ensured to have enough safety and comfort. The separated road surface is a road surface with larger adhesive force difference on two sides, and a vehicle easily slips when started on the separated road surface, so that the vehicle is caused to yaw, the comfort of the vehicle is reduced due to the yaw, and potential safety hazards exist.

Therefore, how the vehicle starts smoothly on the separated road surface is a hot spot of research.

Disclosure of Invention

The embodiment of the application provides a starting method of a separated road surface and a vehicle, which can improve the safety and comfort of the vehicle when starting on the separated road surface, and the technical scheme is as follows:

In one aspect, a method of starting a separated road surface is provided, the method comprising:

Under the condition that a target vehicle starts on a separated road surface, applying braking force to target wheels of the target vehicle and determining adhesive force of two side wheels of the target vehicle, wherein the separated road surface comprises a low-attachment road surface and a high-attachment road surface, the two side wheels comprise wheels positioned on the low-attachment road surface and wheels positioned on the high-attachment road surface, and the target wheels are wheels positioned on the low-attachment road surface;

Determining a target rear wheel steering angle of the target vehicle based on the adhesion and the driving force of wheels on both sides of the target vehicle, the target rear wheel steering angle being used for weakening yaw when the target vehicle starts;

And controlling rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting driving distance of the target vehicle.

In one possible embodiment, in the case that the target vehicle starts on a separated road, the applying a braking force to the target wheel of the target vehicle and determining the adhesion force of the wheels on both sides of the target vehicle includes:

controlling a braking system of a target vehicle to apply braking force to the target wheel under the condition that the target vehicle starts on a separated road surface;

The adhesion force of the wheels on both sides of the target vehicle is determined based on the slip ratio of the wheels on both sides of the target vehicle.

In one possible embodiment, the determining the adhesion force of the two side wheels of the target vehicle based on the slip ratio of the two side wheels of the target vehicle includes:

determining attachment coefficients of wheels on both sides of the target vehicle based on slip rates of the wheels on both sides of the target vehicle;

The adhesion force of the wheels on both sides of the target vehicle is determined based on the pressure applied by the target vehicle to the separated road surface and the adhesion coefficient of the wheels on both sides of the target vehicle.

In one possible embodiment, the determining the target rear wheel steering angle of the target vehicle based on the adhesion and the driving force of the wheels on both sides of the target vehicle includes:

Subtracting the adhesive force of the wheels at the two sides of the target vehicle to obtain a wheel adhesive force difference value of the target vehicle;

Subtracting the driving forces of the wheels at two sides of the target vehicle to obtain a wheel driving force difference value of the target vehicle;

the target rear wheel steering angle is determined based on the wheel adhesion difference and the wheel driving force difference of the target vehicle.

In one possible embodiment, the determining the target rear wheel steering angle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle includes:

Determining a yaw rate of the target vehicle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle;

And determining the rear wheel steering angle corresponding to the yaw rate as the target rear wheel steering angle.

In one possible embodiment, the determining the yaw rate of the target vehicle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle includes:

Inquiring a target table by adopting the wheel adhesion difference value and the wheel driving force difference value to obtain the yaw rate, wherein the target table comprises a plurality of candidate yaw rates, and one candidate yaw rate corresponds to a group of candidate wheel adhesion difference values and candidate wheel driving force difference values;

Or substituting the wheel adhesion difference value and the wheel driving force difference value into target relation data to obtain the yaw rate, wherein the target relation data is obtained by fitting a plurality of candidate wheel adhesion difference values, a plurality of candidate wheel driving force difference values and a plurality of candidate yaw rates.

In one possible embodiment, the controlling the rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting travel distance of the target vehicle includes:

determining a steering angle correction coefficient based on the starting travel distance, wherein the steering angle correction coefficient is positively correlated with the starting travel distance;

multiplying the target rear wheel steering angle by the steering angle correction coefficient to obtain a reference steering angle;

and controlling the rear wheels of the target vehicle to steer at the reference steering angle.

In one possible embodiment, after the controlling the rear wheels of the target vehicle to steer at the reference steering angle, the method further includes:

Continuously updating a steering angle correction coefficient along with the change of the starting and running distance of the target vehicle;

continuously updating the reference steering angle based on the target rear wheel steering angle and the continuously updated steering angle correction coefficient until the reference steering angle is updated to the target rear wheel steering angle;

and controlling the rear wheels of the target vehicle to steer at the continuously updated reference steering angle.

In one possible embodiment, after the controlling the rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting travel distance of the target vehicle, the method further includes:

and under the condition that the starting running distance of the target vehicle reaches the preset running distance or the speed of the target vehicle reaches the preset speed, controlling the rear wheels of the target vehicle to steer without being based on the target rear wheel steering angle and the starting running distance of the target vehicle.

In one aspect, there is provided a launch device for separating a road surface, the device comprising:

The vehicle comprises an adhesion determining module, a braking force determining module and a driving force determining module, wherein the adhesion determining module is used for applying braking force to target wheels of a target vehicle and determining adhesion of two side wheels of the target vehicle under the condition that the target vehicle starts on a separated road surface, the separated road surface comprises a low-adhesion road surface and a high-adhesion road surface, the two side wheels comprise wheels positioned on the low-adhesion road surface and wheels positioned on the high-adhesion road surface, and the target wheels are wheels positioned on the low-adhesion road surface;

a rear wheel steering angle determination module configured to determine a target rear wheel steering angle of the target vehicle based on an adhesion force and a driving force of wheels on both sides of the target vehicle, the target rear wheel steering angle being configured to attenuate yaw when the target vehicle starts;

And the control module is used for controlling the rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting driving distance of the target vehicle.

In one possible implementation, the adhesion determination module is used for controlling a braking system of a target vehicle to apply braking force to the target wheel under the condition that the target vehicle starts on a separated road surface, and determining the adhesion of the two side wheels of the target vehicle based on the slip rate of the two side wheels of the target vehicle.

In one possible embodiment, the adhesion determination module is configured to determine adhesion coefficients of the wheels of the target vehicle based on slip rates of the wheels of the target vehicle, and determine adhesion of the wheels of the target vehicle based on pressure applied by the target vehicle to the separated road surface and the adhesion coefficients of the wheels of the target vehicle.

In one possible implementation manner, the rear wheel steering angle determining module is configured to subtract the adhesive forces of the wheels on two sides of the target vehicle to obtain a wheel adhesive force difference value of the target vehicle, subtract the driving forces of the wheels on two sides of the target vehicle to obtain a wheel driving force difference value of the target vehicle, and determine the target rear wheel steering angle based on the wheel adhesive force difference value and the wheel driving force difference value of the target vehicle.

In one possible embodiment, the rear wheel steering angle determining module is configured to determine a yaw rate of the target vehicle based on a wheel adhesion difference value and a wheel driving force difference value of the target vehicle, and determine a rear wheel steering angle corresponding to the yaw rate as the target rear wheel steering angle.

In one possible implementation manner, the rear wheel steering angle determining module is configured to query a target table with the wheel adhesion difference and the wheel driving force difference to obtain the yaw rate, where the target table includes a plurality of candidate yaw rates, and one of the candidate yaw rates corresponds to a set of candidate wheel adhesion difference and candidate wheel driving force difference, or substitutes the wheel adhesion difference and the wheel driving force difference into target relationship data to obtain the yaw rate, and the target relationship data is obtained by fitting a plurality of candidate wheel adhesion differences, a plurality of candidate wheel driving force differences, and a plurality of candidate yaw rates.

In one possible implementation manner, the control module is used for determining a steering angle correction coefficient based on the starting driving distance, wherein the steering angle correction coefficient is positively correlated with the starting driving distance, multiplying the target rear wheel steering angle by the steering angle correction coefficient to obtain a reference steering angle, and controlling rear wheels of the target vehicle to steer at the reference steering angle.

In one possible implementation, the control module is further configured to continuously update a steering angle correction coefficient according to a change of a starting driving distance of the target vehicle, continuously update a reference steering angle based on the target rear wheel steering angle and the continuously updated steering angle correction coefficient until the reference steering angle is updated to the target rear wheel steering angle, and control rear wheels of the target vehicle to steer at the continuously updated reference steering angle.

In one possible implementation manner, the control module is further configured to control the rear wheels of the target vehicle to steer, without further based on the target rear wheel steering angle and the starting travel distance of the target vehicle, when the starting travel distance of the target vehicle reaches a preset travel distance or the vehicle speed of the target vehicle reaches a preset vehicle speed.

In one aspect, a vehicle is provided that includes one or more processors and one or more memories having at least one program code stored therein that is loaded and executed by the one or more processors to perform operations performed by the split road launch method.

In one aspect, a computer readable storage medium having stored therein at least one program code loaded and executed by a processor to perform operations performed by the method of starting off a road surface is provided.

According to the technical scheme provided by the embodiment of the application, under the condition that the target vehicle starts on the separated road surface, braking force is applied to the wheels (wheels on the low attaching side) of the target vehicle on the low attaching road surface, and the adhesive force of the wheels (wheels on the low attaching side and wheels on the high attaching side) on the two sides of the target vehicle is determined. A target rear wheel steering angle of the target vehicle for weakening yaw at the start of the target vehicle is determined based on the adhesion and driving forces of wheels on both sides of the target vehicle. And controlling the rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting running distance of the target vehicle, so that the yaw of the target vehicle is counteracted by the steering of the rear wheels, and the safety and the comfort of the target vehicle in starting are improved.

Drawings

FIG. 1 is a schematic illustration of an implementation environment of a method for starting a split road surface according to an embodiment of the present application;

FIG. 2 is a flow chart of a method for starting a separated road surface according to an embodiment of the present application;

FIG. 3 is a flow chart of another method of starting a split pavement according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a starting device for separating a road surface according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of a vehicle according to an embodiment of the present application.

Detailed Description

The technical scheme of the application will be clearly and thoroughly described below with reference to the accompanying drawings. In the description of the embodiment of the present application, unless otherwise indicated, "/" means or, for example, a/B may mean a or B, "and/or" in the text is only one association relationship describing the association object, and it means that there may be three relationships, for example, a and/or B, three cases where a exists alone, a and B exist together, and B exists alone, and further, "a plurality" means two or more in the description of the embodiment of the present application.

In the following, the terms "first", "second" are used for descriptive purposes only and are not to be construed as implying or implying relative importance or implying a number of reflected technical features. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature.

In order to describe the technical solution provided by the embodiments of the present application, some nouns related to the embodiments of the present application are first described.

The road surface is separated, namely the road surface with larger difference of adhesive force at two sides is separated, and the vehicle can sideslip to the low adhesive force side (the side with low adhesive force) because of the difference of the adhesive force at two sides of the vehicle, so that the vehicle body generates larger yaw, and danger is easy to cause. For example, a road surface formed by splicing an ice surface and a cement road surface is a separated road surface, one side of a vehicle is positioned on the ice surface, and the other side of the vehicle is positioned on the cement road surface, and because the adhesive force of the ice surface is smaller, the adhesive force of the cement road surface is larger, and the vehicle can yaw towards the ice surface when starting.

Differential, which is a device that allows the left and right wheels to rotate at different speeds, is particularly important when the vehicle is turning. When the automobile runs straight, the rotation speeds of the left wheel and the right wheel are the same, the differential mechanism does not work, but when the automobile turns, the rotation speeds of the inner wheel and the outer wheel are different, the differential mechanism allows the wheels to rotate at different speeds, the wheels are kept to roll purely, the abrasion of the wheels is reduced, and the running safety is improved.

An open differential, also known as an open differential, is a common automotive differential type. It allows the rotational speed of the two driving wheels to be different when the vehicle turns to adapt to the turning requirement of the vehicle. When the vehicle runs in a straight line, the rotation speeds of the driving wheels at two sides are the same, the gears in the differential mechanism rotate at the same speed, and when the vehicle turns, the rotation speeds of the inner and outer wheels are different, the gears in the differential mechanism can rotate to balance the rotation speed difference between the wheels, so that the vehicle can turn smoothly.

The slip ratio is a parameter describing the relative motion of the wheel and the road surface, and is used for measuring the relative slip condition between the wheel imprinting and the road surface when the wheel brakes or accelerates during straight running. A slip ratio of 0% means that the distance travelled by the vehicle is equal to the distance travelled by the tread of the wheel, while a slip ratio of 100% means that the wheel does not push the body forward.

Adhesion coefficient, which is an important indicator for measuring the friction between a wheel and a road surface, reflects the adhesion capability of the wheel under specific road surface conditions. The magnitude of the sticking coefficient directly affects the acceleration, braking and cornering performance of the vehicle, and the driving safety under complex weather conditions. The sticking coefficient is a dimensionless ratio, typically expressed as the ratio of the tangential force to the normal force of the wheel.

Yaw rate, the speed at which the vehicle rotates about a vertical axis during movement, is one of the important parameters for measuring the dynamic stability of the vehicle.

Rear wheel steering, a vehicle function, which allows the rear wheels and the front wheels of the vehicle to realize independent steering, thereby improving the operability and stability of the vehicle. Compared with the traditional front wheel steering, the rear wheel steering can provide more flexible and safe driving experience under different driving conditions, such as high-speed driving, emergency avoidance and the like.

In the related art, a starting differential is generally configured in a vehicle, when the vehicle starts on a separated road, because one side is a low-traction road and the other side is a high-traction road, according to the principle of the open differential, the rotation speed of the low-traction wheel will rapidly rise, the wheels slip, at this time, the high-traction wheel loses driving force due to the slip of the low-traction wheel, and the high-traction wheel is almost stationary, so that the vehicle cannot normally start.

At this time, if the high-side wheels and the low-side wheels are braked differently, that is, the low-side wheels are braked, the high-side wheels acquire the rotating speed and the driving force according to the principle of starting the differential mechanism (differential speed is not poor), so that the vehicle can start, but the vehicle yaw is serious, and after the technical scheme provided by the embodiment of the application is adopted, the yaw of the vehicle when the vehicle starts on a separated road surface can be relieved, so that the safety and the comfort of the vehicle are improved.

After describing the terms related to the embodiments of the present application, the following describes the implementation environment of the embodiments of the present application, and referring to fig. 1, the implementation environment of the method for starting the separated road surface provided by the embodiments of the present application includes a vehicle terminal 101, a brake controller 102, and a rear wheel steering controller 103.

The in-vehicle terminal 101 is a terminal provided on a vehicle and has data acquisition and data processing capabilities. The vehicle-mounted terminal 101 is connected with a plurality of component controllers and a plurality of sensors of the vehicle in a wired manner, the vehicle-mounted terminal 101 can control the plurality of component controllers of the vehicle, different component controllers can control different vehicle components, and the sensors can collect information related to running of the vehicle. In the embodiment of the present application, the plurality of component controllers include a brake controller 102 and a rear wheel steering controller 103, the brake controller 102 is used for performing independent brake control on different wheels of the vehicle, and the rear wheel steering controller 103 is used for controlling rear wheel steering of the vehicle, that is, controlling steering angle of the rear wheels of the vehicle.

After the implementation environment of the embodiment of the present application is introduced, the application scenario of the technical solution provided by the embodiment of the present application is described below. The technical scheme provided by the embodiment of the application can be applied to various vehicles which are provided with the differential mechanism and can steer the rear wheel, for example, the technical scheme provided by the embodiment of the application can be applied to electric vehicles, hybrid vehicles and fuel vehicles, and the embodiment of the application is not limited to the application.

In the case that the technical scheme provided by the embodiment of the application is applied to the electric vehicle, in response to identifying that the electric vehicle starts on a separated road, braking force is applied to wheels (wheels on the low-attachment side) of the electric vehicle on the low-attachment road, and the adhesive force of the wheels (wheels on the low-attachment side and wheels on the high-attachment side) on two sides of the electric vehicle is determined. Based on the adhesion and the driving force of the wheels on both sides of the electric vehicle, a target rear wheel steering angle of the electric vehicle for weakening yaw at the start of the target vehicle is determined. Based on the target rear wheel steering angle and the starting running distance of the electric vehicle, the rear wheels of the electric vehicle are controlled to steer, so that the yaw of the electric vehicle is counteracted through the steering of the rear wheels, and the safety and the comfort of the electric vehicle in starting are improved.

It should be noted that, the foregoing is described by taking the application of the technical solution provided by the embodiment of the present application to an electric vehicle as an example, and in the case where the technical solution provided by the embodiment of the present application is applied to other types of vehicles, the implementation process and the foregoing description belong to the same inventive concept, and are not repeated herein.

In addition, the technical solution provided in the embodiment of the present application can be applied to other types of vehicles besides the above types of vehicles, and the embodiment of the present application is not limited thereto.

After the implementation environment and the application scenario of the embodiment of the present application are described, the technical solution provided by the embodiment of the present application is described below, referring to fig. 2, taking the implementation main body as an example of the vehicle-mounted terminal, and the method includes the following steps.

201. In the case where the target vehicle starts on a split road surface, the vehicle-mounted terminal applies a braking force to a target wheel of the target vehicle and determines an adhesion force of both side wheels of the target vehicle, the split road surface including a low-attachment road surface and a high-attachment road surface, the both side wheels including a wheel on the low-attachment road surface and a wheel on the high-attachment road surface, the target wheel being a wheel on the low-attachment road surface.

Wherein the target vehicle is a vehicle configured with an open differential and rear wheel steering. The separated road surface comprises a low-adhesion road surface and a high-adhesion road surface, and the adhesion force of the wheels on the low-adhesion road surface is obviously lower than that of the wheels on the high-adhesion road surface, so that under the condition that a target vehicle starts on the separated road surface, the adhesion force of the wheels on two sides of the target vehicle is greatly different, the target wheels on the low-adhesion road surface are braked, and the wheels on the high-adhesion road surface can obtain the rotating speed and the driving force, so that the target vehicle can start. The adhesion force of the wheel can represent the adhesion capability of the wheel on the road surface, the adhesion force is actually the friction force between the wheel and the road surface, the larger the adhesion force of the wheel is, the more difficult the wheel is to slip, and the smaller the adhesion force of the wheel is, the more easy the wheel is to slip.

202. The in-vehicle terminal determines a target rear wheel steering angle of the target vehicle for weakening yaw when the target vehicle starts, based on an adhesion force and a driving force of wheels on both sides of the target vehicle.

The driving force of the wheels refers to the power distributed to the wheels by the power source of the vehicle, and the target rear wheel steering angle refers to the target steering angle of the rear wheel steering when the rear wheel steering control is performed. The principle of reducing the yaw of the target vehicle at the time of starting is to change the traveling direction of the target vehicle by using the rear wheel steering, which is opposite to the yaw direction of the target vehicle, so as to cancel the yaw of the target vehicle.

203. The vehicle-mounted terminal controls rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting travel distance of the target vehicle.

The starting travel distance of the target vehicle is the accumulated travel distance of the target vehicle after starting the current starting.

It should be noted that, the steps 201 to 203 are simple descriptions of the method for starting the separated pavement according to the embodiment of the present application, and the method for starting the separated pavement according to the embodiment of the present application will be described in more detail with reference to fig. 3, and take the execution subject as an example of the vehicle-mounted terminal, and the method includes the following steps.

301. In response to the target vehicle starting, the in-vehicle terminal determines whether the target vehicle starts on a split road surface including a low-grade road surface and a high-grade road surface.

Wherein the target vehicle is a vehicle configured with an open differential and rear wheel steering. The separated road surface comprises a low-adhesion road surface and a high-adhesion road surface, and the adhesion force of the wheels on the low-adhesion road surface is obviously lower than that of the wheels on the high-adhesion road surface, so that the adhesion forces of the wheels on two sides of the target vehicle have larger difference under the condition that the target vehicle starts on the separated road surface. For example, the separated road surface includes an ice surface and a cement road surface, and then the ice surface is a low-attachment road surface and the cement road surface is a high-attachment road surface. The start of the target vehicle refers to a process from the stopped state to the running state of the target vehicle, that is, a process from the power source of the target vehicle from the power output to the start of the power output.

In one possible embodiment, the in-vehicle terminal determines a slip ratio of wheels on both sides of the target vehicle in response to the target vehicle starting. The vehicle-mounted terminal determines whether the target vehicle starts on the separated road surface based on the slip rates of the wheels on the two sides.

Wherein, the both sides wheel includes left side wheel and right side wheel, and the slip ratio can be used for showing the relative motion condition between wheel and the road surface, namely the slip condition. The slip ratio of the wheel is correlated with the adhesion between the wheel and the road surface, so the slip ratio of the wheel can reflect the adhesion of the wheel, thereby reflecting whether the target vehicle starts on the separated road surface.

In the embodiment, in response to the starting of the target vehicle, whether the target vehicle starts on the separated road or not can be directly determined by utilizing the slip rates of the wheels on two sides of the target vehicle, so that the efficiency is high.

For example, in response to the target vehicle starting, the in-vehicle terminal acquires the vehicle speed of the target vehicle and the linear speeds of the wheels on both sides. The vehicle-mounted terminal determines slip rates of wheels on both sides of the target vehicle based on the vehicle speed of the target vehicle and the linear speeds of the wheels on both sides. The vehicle-mounted terminal determines whether the target vehicle starts on the separated road surface based on the difference value between the slip rates of the wheels at the two sides.

For example, in response to the start of the target vehicle, the in-vehicle terminal acquires the vehicle speed of the target vehicle and the angular speeds of the wheels on both sides. The vehicle-mounted terminal multiplies the angular speeds of the wheels at the two sides by the corresponding wheel radius to obtain the linear speeds of the wheels at the two sides. For any wheel of the wheels on two sides, the vehicle-mounted terminal subtracts the speed of the target vehicle from the linear speed of the wheel and then divides the speed of the target vehicle from the linear speed of the wheel to obtain the slip rate of the wheel. And under the condition that the difference value between the slip rates of the wheels at the two sides is smaller than the difference value threshold, the vehicle-mounted terminal determines that the target vehicle is not started on the separated road.

The difference threshold is set by a technician according to practical situations, which is not limited in the embodiment of the present application.

Another embodiment of step 301 is described below.

In one possible embodiment, the in-vehicle terminal acquires the road surface image in the traveling direction of the target vehicle in response to the start of the target vehicle. The in-vehicle terminal determines whether the target vehicle starts on the separated road based on the road image.

The road surface image is an image acquired by a camera in front of the target vehicle. Since the surface characteristics of the low-grade road surface and the high-grade road surface are different, the road surface image can be used to distinguish the low-grade road surface and the high-grade road surface, thereby realizing the identification of the separated road surface.

In this embodiment, it is efficient to determine whether the target vehicle starts on the separated road using the road surface image in the traveling direction.

For example, in response to the start of the target vehicle, the in-vehicle terminal acquires a road surface image in the traveling direction of the target vehicle. And the vehicle-mounted terminal performs feature extraction on the road surface image to obtain the image features of the road surface image. The vehicle-mounted terminal determines whether the target vehicle starts on the separated road surface based on the image characteristics of the road surface image.

For example, in response to the start of the target vehicle, the in-vehicle terminal acquires a road surface image in the traveling direction of the target vehicle. The vehicle-mounted terminal inputs the road surface image into a road surface identification model, and the road surface image is convolved for a plurality of times through the road surface identification model to obtain the image characteristics of the road surface image. And the vehicle-mounted terminal carries out full connection and normalization on the image features of the road surface image through the road surface identification model to obtain the road surface type classification value of the road surface image. And the vehicle-mounted terminal determines that the target vehicle starts on the separated road surface when the road surface type classification value is larger than or equal to the classification value threshold value, and determines that the target vehicle does not start on the separated road surface when the road surface type classification value is smaller than the classification value threshold value.

The road surface recognition model is obtained through training based on a plurality of sample road surface images and marked road surface starting types corresponding to the sample road surface images, wherein the marked road surface starting types are starting on a separated road surface or starting on a non-separated road surface. The classification value threshold is set by the skilled person according to the actual situation, which is not limited by the embodiment of the present application. In some embodiments, the pavement identification model is a classification model.

302. In the case that the target vehicle starts on a separated road, the vehicle-mounted terminal applies a braking force to a target wheel of the target vehicle and determines adhesion forces of two side wheels of the target vehicle, the two side wheels including a wheel on a low-grade road and a wheel on a high-grade road, and the target wheel being a wheel on the low-grade road.

In the case that the target vehicle starts on a separated road, due to different adhesion forces of wheels on two sides of the target vehicle, the wheels on the high-adhesion side generate a moment anticlockwise around the mass center of the target vehicle, and the moment can cause the target vehicle to yaw. The target wheels on the low-grade road surface are braked, so that the wheels on the high-grade road surface can obtain rotating speed and driving force, and the target vehicle can start. The adhesion force of the wheel can represent the adhesion capability of the wheel on the road surface, the adhesion force is actually the friction force between the wheel and the road surface, and the larger the adhesion force of the wheel is, the less easy the wheel is to slip. The smaller the adhesion force of the wheel, the more likely the wheel slips.

In one possible embodiment, in a case where the target vehicle starts on a separated road, the in-vehicle terminal controls the brake system of the target vehicle to apply a braking force to the target wheel. The in-vehicle terminal determines the adhesion force of the wheels on both sides of the target vehicle based on the slip ratio of the wheels on both sides of the target vehicle.

The vehicle-mounted terminal sends a braking control command to the braking controller, and then the braking controller can execute the braking control command, namely control other components in the braking controller to execute actions corresponding to the braking control command. Since the target vehicle is provided with the open differential, after the braking force is applied to the wheels on the low-attachment road surface, the wheels on the high-attachment road surface can obtain the rotational speed and the driving force according to the principle of the open differential (differential torque is not poor), so that the target vehicle can start. The slip ratio of the wheel is closely related to the adhesion of the wheel, so the adhesion of the wheel can be determined by using the slip ratio of the wheel, and it should be noted that the adhesion of the wheel refers to the adhesion between the wheel and the road surface.

In this embodiment, in the case where the target vehicle starts on the separated road, the control brake system applies the braking force to the wheels on the low-attachment road, so that the target vehicle can achieve the start by the adhesion force of the wheels on the high-attachment road. Since the slip rate of the wheel is closely related to the adhesion, the adhesion of the wheel can be determined by using the slip rate of the wheel, and the determination efficiency of the adhesion is high.

In order to more clearly describe the above embodiments, the above embodiments will be described below in sections.

The first part controls a braking system of the target vehicle to apply braking force to the target wheel when the target vehicle starts on a separated road surface.

In one possible embodiment, in the case where the target vehicle starts on a separated road, the in-vehicle terminal determines the target wheel located on a low-attachment road from the wheels on both sides. The vehicle-mounted terminal sends a braking control instruction to a braking controller of the braking system, wherein the braking control instruction carries a wheel identifier of the target wheel, and the braking control instruction is used for indicating to apply braking force to the target wheel. The brake controller controls a brake component corresponding to a target wheel in the brake system to apply a braking force to the target wheel based on the brake control command.

The second part, the vehicle-mounted terminal, determines the adhesion force of the wheels on both sides of the target vehicle based on the slip ratio of the wheels on both sides of the target vehicle.

In one possible embodiment, the in-vehicle terminal determines the adhesion coefficient of the both side wheels of the target vehicle based on the slip ratio of the both side wheels of the target vehicle. The in-vehicle terminal determines the adhesion force of the wheels on both sides of the target vehicle based on the pressure applied by the target vehicle to the separated road surface and the adhesion coefficient of the wheels on both sides of the target vehicle.

Wherein the pressure applied by the target vehicle to the split road surface is a component force of the target vehicle in a direction perpendicular to the split road surface.

In this embodiment, the slip ratio of the wheels on both sides is used to determine the adhesion coefficient of the wheels on both sides, and the pressure applied by the target vehicle to the separated road surface and the adhesion coefficient can be used to determine the adhesion force of the wheels on both sides, so that the determination of the adhesion force is accurate.

For example, the vehicle-mounted terminal uses the slip rate of the wheels at both sides of the target vehicle to query in the slip rate-adhesion coefficient curve of the target vehicle, so as to obtain the adhesion coefficient of the wheels at both sides. The vehicle-mounted terminal multiplies the pressure applied by the target vehicle to the separated road surface by the adhesion coefficients of the wheels at the two sides of the target vehicle to obtain the adhesion force of the wheels at the two sides of the target vehicle.

The slip rate-adhesion coefficient curve is obtained by a technical staff performing real vehicle calibration or simulation on the target vehicle, can reflect the corresponding relation between the slip rate and the adhesion coefficient of the target vehicle, and can be used for rapidly inquiring the adhesion coefficient corresponding to a certain slip rate.

For example, the vehicle-mounted terminal adopts the slip rate of the wheels at the two sides of the target vehicle to inquire in a slip rate-attachment coefficient curve of the target vehicle, and obtains the attachment coefficients of the wheels at the two sides. The vehicle-mounted terminal determines the pressure applied by the target vehicle to the separated road surface based on the mass of the target vehicle and the included angle between the separated road surface where the target vehicle is located and the horizontal plane. The vehicle-mounted terminal multiplies the pressure applied by the target vehicle to the separated road surface by the adhesion coefficients of the wheels at the two sides of the target vehicle to obtain the adhesion force of the wheels at the two sides of the target vehicle.

The included angle between the separated road surface where the target vehicle is located and the horizontal plane is determined by the gyroscope or the level meter of the target vehicle, which is not limited in the embodiment of the application.

Another embodiment of the second part will be described below.

In one possible embodiment, the vehicle-mounted terminal inputs the slip ratio of the two side wheels of the target vehicle and the mass of the target vehicle into an adhesion prediction model, processes the slip ratio of the two side wheels and the mass of the target vehicle through the adhesion prediction model, and outputs the adhesion of the two side wheels of the target vehicle.

The adhesive force prediction model is obtained through training based on a plurality of first sample data and labeling adhesive force corresponding to each first sample data, and has the capability of predicting adhesive force, and one first sample data comprises a group of sample slip rate and sample quality. In some embodiments, the adhesion prediction model is a regression model.

In the above embodiment, the adhesion force of the wheels on both sides of the target vehicle is determined by using the adhesion force prediction model, so that the efficiency is high.

For example, the vehicle-mounted terminal inputs the slip ratio of the wheels at both sides of the target vehicle and the mass of the target vehicle into an adhesion prediction model, and performs feature extraction on the slip ratio of the wheels at both sides and the mass of the target vehicle through the adhesion prediction model to obtain an adhesion prediction feature. And the vehicle-mounted terminal maps the adhesion prediction characteristics through the adhesion prediction model to obtain the adhesion of wheels on two sides of the target vehicle.

For example, the vehicle-mounted terminal inputs the slip rate of the wheels at two sides of the target vehicle and the mass of the target vehicle into an adhesion prediction model, and the slip rate of the wheels at two sides and the mass of the target vehicle are fully connected for a plurality of times through the adhesion prediction model to obtain an adhesion prediction characteristic. And the vehicle-mounted terminal carries out full connection and normalization on the adhesion prediction characteristics through the adhesion prediction model to obtain the adhesion of wheels on two sides of the target vehicle.

303. The in-vehicle terminal determines a target rear wheel steering angle of the target vehicle for weakening yaw when the target vehicle starts, based on an adhesion force and a driving force of wheels on both sides of the target vehicle.

The driving force of the wheels refers to the power distributed to the wheels by the power source of the vehicle, and the target rear wheel steering angle refers to the target steering angle of the rear wheel steering when the rear wheel steering control is performed. The principle of reducing the yaw of the target vehicle at the time of starting is to change the traveling direction of the target vehicle by using the rear wheel steering, which is opposite to the yaw direction of the target vehicle, so as to cancel the yaw of the target vehicle. In some embodiments, the driving force of the wheels on two sides is obtained by the vehicle-mounted terminal from the bus signal, so that the reliability is high.

In one possible implementation manner, the vehicle-mounted terminal subtracts the adhesive force of the wheels on two sides of the target vehicle to obtain a wheel adhesive force difference value of the target vehicle. The vehicle-mounted terminal subtracts the driving forces of the wheels on the two sides of the target vehicle to obtain a wheel driving force difference value of the target vehicle. The in-vehicle terminal determines the target rear wheel steering angle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle.

Wherein the wheel adhesion difference is used to represent the difference in adhesion of both side wheels of the target vehicle, the wheel driving force difference is used to represent the difference in driving force of both side wheels of the target vehicle, and the difference in adhesion of both side wheels and the difference in driving force affect the yaw amplitude of the target vehicle, and therefore, the target rear wheel steering angle for weakening the yaw can be determined using the difference in adhesion of both side wheels and the difference in driving force.

In this embodiment, the target rear-wheel steering angle is determined using the difference in adhesion and the difference in driving force of the wheels on both sides of the target vehicle, that is, the target rear-wheel steering angle is determined in combination with the factor affecting the yaw of the target vehicle, and the accuracy of the target rear-wheel steering angle is high.

In order to more clearly describe the above embodiment, a manner of determining the target rear wheel steering angle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle in the above embodiment is described below.

In one possible embodiment, the in-vehicle terminal determines the yaw rate of the target vehicle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle. The vehicle-mounted terminal determines the rear wheel steering angle corresponding to the yaw rate as the target rear wheel steering angle.

The yaw rate may represent the intensity of the yaw of the target vehicle or the yaw width of the target vehicle. In general, the larger the difference in the adhesion of the wheels on both sides of the target vehicle, the larger the difference in the driving force, the larger the yaw rate of the target vehicle. In the above embodiment, the yaw rate is determined using the wheel adhesion difference value and the wheel driving force difference value, but the yaw rate is not obtained directly using the rotation sensor and the acceleration sensor, because the reliability of the data measured by the rotation sensor and the acceleration sensor is low when the vehicle is traveling at a low speed and the vehicle body is unstable.

In this embodiment, the yaw rate of the target vehicle is determined using the wheel adhesion difference and the wheel driving force difference, and the target rear-wheel steering angle is determined using the correspondence between the yaw rate and the rear-wheel steering angle, with high accuracy.

The above embodiments are described below by way of two examples.

In example 1, the vehicle-mounted terminal uses the wheel adhesion difference and the wheel driving force difference to query in a target table, and obtains the yaw rate, where the target table includes a plurality of candidate yaw rates, and one of the candidate yaw rates corresponds to a set of candidate wheel adhesion difference and candidate wheel driving force difference. The in-vehicle terminal determines the target rear wheel steering angle corresponding to the yaw rate from among the plurality of candidate rear wheel steering angles.

In example 2, the vehicle-mounted terminal substitutes the wheel adhesion difference and the wheel driving force difference into target relationship data, which is obtained by fitting a plurality of candidate wheel adhesion differences, a plurality of candidate wheel driving force differences, and a plurality of candidate yaw rates, to obtain the yaw rate. The in-vehicle terminal determines the target rear wheel steering angle corresponding to the yaw rate from among the plurality of candidate rear wheel steering angles.

Another embodiment of step 303 is described below.

In one possible implementation manner, the vehicle-mounted terminal inputs the adhesive force and the driving force of the wheels at two sides of the target vehicle into a steering angle prediction model, and the steering angle prediction model is used for processing the adhesive force and the driving force of the wheels at two sides to obtain the target rear wheel steering angle of the target vehicle.

The steering angle prediction model is obtained through training based on a plurality of second sample data and labeled rear wheel steering angles corresponding to the second sample data, and has the capability of determining the rear wheel steering angles. In some embodiments, the steering angle prediction model is a regression model.

For example, the vehicle-mounted terminal inputs the adhesive force and the driving force of the wheels at two sides of the target vehicle into a steering angle prediction model, and the characteristics of the adhesive force and the driving force of the wheels at two sides are extracted through the steering angle prediction model to obtain steering angle prediction characteristics. And the vehicle-mounted terminal maps the steering angle prediction characteristics through the steering angle prediction model to obtain the target rear wheel steering angle of the target vehicle.

For example, the vehicle-mounted terminal inputs the adhesive force and the driving force of the wheels at two sides of the target vehicle into a steering angle prediction model, and the adhesive force and the driving force of the wheels at two sides are fully connected for a plurality of times through the steering angle prediction model to obtain steering angle prediction characteristics. And the vehicle-mounted terminal carries out full connection and normalization on the steering angle prediction characteristics through the steering angle prediction model to obtain the target rear wheel steering angle of the target vehicle.

304. The vehicle-mounted terminal controls rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting travel distance of the target vehicle.

In one possible embodiment, the vehicle-mounted terminal determines a steering angle correction coefficient based on the starting travel distance, the steering angle correction coefficient being positively correlated with the starting travel distance. And the vehicle-mounted terminal multiplies the target rear wheel steering angle by the steering angle correction coefficient to obtain a reference steering angle. The vehicle-mounted terminal controls the rear wheels of the target vehicle to steer at the reference steering angle.

In the above embodiments, since the slip ratio accuracy of the wheels calculated from the stationary phase to the starting phase of the vehicle is limited, a steering angle correction coefficient is determined by using the starting travel distance, and the target rear wheel steering angle is corrected by using the steering angle correction coefficient, that is, the steering amplitude of the rear wheels is limited within a certain starting travel distance, so that the vehicle yaw is prevented from being excessively corrected. The value range of the steering angle correction coefficient is more than 0 and less than or equal to 1.

For example, the vehicle-mounted terminal determines a starting travel distance range to which the starting travel distance belongs. And the vehicle-mounted terminal determines the steering angle correction coefficient corresponding to the starting travel distance range as the steering angle correction coefficient corresponding to the starting travel distance. And the vehicle-mounted terminal multiplies the target rear wheel steering angle by the steering angle correction coefficient to obtain a reference steering angle. The in-vehicle terminal transmits a rear-wheel steering instruction to a rear-wheel steering controller of a target vehicle, the rear-wheel steering instruction carrying the reference steering angle so that the rear-wheel steering controller controls rear wheels of the target vehicle to steer at the reference steering angle based on the rear-wheel steering instruction.

The correspondence between the starting travel distance range and the steering angle correction coefficient is set by a technician according to actual conditions, which is not limited by the embodiment of the present application.

Alternatively, the following steps can be performed on the basis of the above embodiments.

In one possible embodiment, the vehicle-mounted terminal continuously updates the steering angle correction coefficient as the starting travel distance of the target vehicle changes. The vehicle-mounted terminal continuously updates the reference steering angle based on the target rear wheel steering angle and the continuously updated steering angle correction coefficient until the reference steering angle is updated to the target rear wheel steering angle. The vehicle-mounted terminal controls the rear wheels of the target vehicle to steer at the continuously updated reference steering angle.

In this embodiment, as the starting travel distance of the target vehicle increases, the steering angle correction coefficient also gradually increases, so that the calculated reference steering angle also gradually increases, and does not increase until the calculated reference steering angle increases to the target rear wheel steering angle, thereby realizing gradient rear wheel steering control and improving the effect of yaw control on the target vehicle.

Optionally, after step 304, the in-vehicle terminal is also able to perform step 305 described below.

305. And under the condition that the starting running distance of the target vehicle reaches the preset running distance or the speed of the target vehicle reaches the preset speed, the vehicle-mounted terminal does not control the rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting running distance of the target vehicle.

The fact that the starting travel distance reaches the preset travel distance and the speed of the target vehicle reaches the preset speed indicates that the target vehicle has completed a starting stage, and therefore yaw of the target vehicle in the starting stage is not required to be controlled. The preset travel distance and the preset vehicle speed are set by a technician according to actual conditions, which is not limited in the embodiment of the present application.

Any combination of the above optional solutions may be adopted to form an optional embodiment of the present application, which is not described herein.

Fig. 4 is a schematic structural diagram of a starting device for separating a road surface according to an embodiment of the present application, and referring to fig. 4, the device includes an adhesion determining module 401, a rear wheel steering angle determining module 402, and a control module 403.

An adhesion determination module 401, configured to apply a braking force to a target wheel of a target vehicle and determine adhesion of two side wheels of the target vehicle in a case where the target vehicle starts on a separated road surface, where the separated road surface includes a low-adhesion road surface and a high-adhesion road surface, the two side wheels include a wheel on the low-adhesion road surface and a wheel on the high-adhesion road surface, and the target wheel is a wheel on the low-adhesion road surface;

A rear wheel steering angle determination module 402 for determining a target rear wheel steering angle of the target vehicle based on the adhesion and driving forces of both wheels of the target vehicle, the target rear wheel steering angle being used to attenuate yaw when the target vehicle starts;

the control module 403 is configured to control the rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting travel distance of the target vehicle.

In one possible implementation, the adhesion determination module 401 is configured to control a braking system of the target vehicle to apply a braking force to the target wheel in a case where the target vehicle starts on a separated road, and determine adhesion of the two wheels of the target vehicle based on a slip ratio of the two wheels of the target vehicle.

In one possible implementation, the adhesion determination module 401 is configured to determine adhesion coefficients of the wheels of the target vehicle based on slip rates of the wheels of the target vehicle, and determine adhesion of the wheels of the target vehicle based on pressure applied by the target vehicle to the separated road surface and the adhesion coefficients of the wheels of the target vehicle.

In one possible implementation, the rear wheel steering angle determining module 402 is configured to subtract the adhesion forces of the wheels on both sides of the target vehicle to obtain a wheel adhesion force difference of the target vehicle, subtract the driving forces of the wheels on both sides of the target vehicle to obtain a wheel driving force difference of the target vehicle, and determine the target rear wheel steering angle based on the wheel adhesion force difference and the wheel driving force difference of the target vehicle.

In one possible implementation, the rear wheel steering angle determining module 402 is configured to determine a yaw rate of the target vehicle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle, and determine a rear wheel steering angle corresponding to the yaw rate as the target rear wheel steering angle.

In a possible implementation manner, the rear wheel steering angle determining module 402 is configured to query a target table using the wheel adhesion difference and the wheel driving force difference to obtain the yaw rate, where the target table includes a plurality of candidate yaw rates, and one of the candidate yaw rates corresponds to a set of candidate wheel adhesion difference and candidate wheel driving force difference, or substitutes the wheel adhesion difference and the wheel driving force difference into target relationship data, where the target relationship data is obtained by fitting a plurality of candidate wheel adhesion differences, a plurality of candidate wheel driving force differences, and a plurality of candidate yaw rates.

In one possible implementation, the control module 403 is configured to determine a steering angle correction coefficient based on the starting distance, where the steering angle correction coefficient is positively correlated with the starting distance, multiply the target rear wheel steering angle with the steering angle correction coefficient to obtain a reference steering angle, and control the rear wheels of the target vehicle to steer at the reference steering angle.

In one possible implementation, the control module 403 is further configured to continuously update the steering angle correction coefficient according to a change of a starting driving distance of the target vehicle, continuously update the reference steering angle based on the target rear wheel steering angle and the continuously updated steering angle correction coefficient until the reference steering angle is updated to the target rear wheel steering angle, and control the rear wheels of the target vehicle to steer at the continuously updated reference steering angle.

In one possible implementation, the control module 403 is further configured to control the rear wheels of the target vehicle to steer when the starting distance of the target vehicle reaches a preset running distance or when the speed of the target vehicle reaches a preset speed, without further based on the target rear wheel steering angle and the starting distance of the target vehicle.

It should be noted that, when the vehicle starts on the separated road, the starting device for separating the road provided by the embodiment only uses the division of the functional modules to illustrate, in practical application, the function allocation may be completed by different functional modules according to the need, that is, the internal structure of the computer device is divided into different functional modules to complete all or part of the functions described above. In addition, the starting device for the separated pavement and the starting method for the separated pavement provided in the foregoing embodiments belong to the same concept, and specific implementation processes of the starting device for the separated pavement are detailed in the method embodiments, which are not repeated herein.

The embodiment of the application also provides a vehicle, and fig. 5 is a schematic structural diagram of the vehicle.

In general, the vehicle 500 includes one or more processors 501 and one or more memories 502.

Processor 501 may include one or more processing cores, such as a 4-core processor, a 5-core processor, and the like. The processor 501 may be implemented in at least one hardware form of DSP (DIGITAL SIGNAL Processing), FPGA (Field-Programmable gate array), PLA (Programmable Logic Array ). The processor 501 may also include a main processor, which is a processor for processing data in a wake-up state, also referred to as a CPU (Central Processing Unit ), and a coprocessor, which is a low-power processor for processing data in a standby state. In some embodiments, the processor 501 may integrate a GPU (Graphics Processing Unit, image processor) for rendering and drawing of content required to be displayed by the display screen. In some embodiments, the processor 501 may also include an AI (ARTIFICIAL INTELLIGENCE ) processor for processing computing operations related to machine learning.

Memory 502 may include one or more computer-readable storage media, which may be non-transitory. Memory 502 may also include high-speed random access memory, as well as non-volatile memory, such as one or more magnetic disk storage devices, flash memory storage devices. In some embodiments, a non-transitory computer readable storage medium in memory 502 is used to store at least one computer program for execution by processor 501 to implement the method of starting a split pavement provided by an embodiment of the method of the present application.

Those skilled in the art will appreciate that the configuration shown in fig. 5 is not limiting of the vehicle 500 and may include more or fewer components than shown, or may combine certain components, or may employ a different arrangement of components.

In addition, the device provided by the embodiment of the application can be a chip, a component or a module, and the chip can comprise a processor and a memory which are connected, wherein the memory is used for storing instructions, and when the processor calls and executes the instructions, the chip can be made to execute the method for separating the road surface from the road surface.

The present embodiment also provides a computer readable storage medium having stored therein computer program code which, when run on a computer, causes the computer to perform the above-mentioned related method steps to implement a method for separating a road surface as provided in the above-mentioned embodiments.

The present embodiment also provides a computer program product which, when run on a computer, causes the computer to perform the above-mentioned related steps to implement a method of separating a road surface as provided in the above-mentioned embodiments.

The apparatus, the computer readable storage medium, the computer program product, or the chip provided in this embodiment are used to execute the corresponding method provided above, and therefore, the advantages achieved by the apparatus, the computer readable storage medium, the computer program product, or the chip can refer to the advantages of the corresponding method provided above, which are not described herein.

It will be appreciated by those skilled in the art that, for convenience and brevity of description, only the above-described division of the functional modules is illustrated, and in practical application, the above-described functional allocation may be performed by different functional modules according to needs, i.e. the internal structure of the apparatus is divided into different functional modules to perform all or part of the functions described above.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of modules or units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another apparatus, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other forms.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the application is subject to the protection scope of the claims.

Claims

1. A method for starting on a separated road surface, characterized in that the method comprises:

When the target vehicle starts on a separated road surface, a braking force is applied to a target wheel of the target vehicle and adhesion of wheels on both sides of the target vehicle is determined, wherein the separated road surface includes a low-adhesion road surface and a high-adhesion road surface, the wheels on both sides include wheels located on the low-adhesion road surface and wheels located on the high-adhesion road surface, and the target wheel is a wheel located on the low-adhesion road surface;

Determine a target rear wheel steering angle of the target vehicle based on the adhesion and driving force of the wheels on both sides of the target vehicle, wherein the target rear wheel steering angle is used to reduce the yaw of the target vehicle when starting;

The step of determining a target rear wheel steering angle of the target vehicle based on the adhesion and driving force of the wheels on both sides of the target vehicle comprises:

Subtracting the adhesion of the wheels on both sides of the target vehicle to obtain the wheel adhesion difference of the target vehicle; subtracting the driving force of the wheels on both sides of the target vehicle to obtain the wheel driving force difference of the target vehicle; determining the target rear wheel steering angle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle;

Based on the target rear wheel steering angle and the starting travel distance of the target vehicle, the rear wheels of the target vehicle are controlled to steer.

2. The method according to claim 1, characterized in that, when the target vehicle starts on a separated road surface, applying a braking force to the target wheels of the target vehicle and determining the adhesion of the wheels on both sides of the target vehicle comprises:

When the target vehicle starts on a separated road surface, controlling a braking system of the target vehicle to apply a braking force to the target wheel;

Based on the slip rates of the wheels on both sides of the target vehicle, the adhesion of the wheels on both sides of the target vehicle is determined.

3. The method according to claim 2, characterized in that the determining the adhesion of the wheels on both sides of the target vehicle based on the slip rates of the wheels on both sides of the target vehicle comprises:

Determining the adhesion coefficients of the wheels on both sides of the target vehicle based on the slip rates of the wheels on both sides of the target vehicle;

The adhesion of the wheels on both sides of the target vehicle is determined based on the pressure applied by the target vehicle to the separated road surface and the adhesion coefficients of the wheels on both sides of the target vehicle.

4. The method according to claim 1, characterized in that the determining the target rear wheel steering angle based on the wheel adhesion difference and wheel driving force difference of the target vehicle comprises:

Determining a yaw rate of the target vehicle based on a wheel adhesion difference and a wheel driving force difference of the target vehicle;

The rear wheel steering angle corresponding to the yaw angular velocity is determined as the target rear wheel steering angle.

5. The method according to claim 4, characterized in that the determining the yaw rate of the target vehicle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle comprises:

The wheel adhesion difference and the wheel driving force difference are used to query in a target table to obtain the yaw rate, wherein the target table includes a plurality of candidate yaw rates, and one candidate yaw rate corresponds to a group of candidate wheel adhesion difference and candidate wheel driving force difference;

Alternatively, the wheel adhesion difference and the wheel driving force difference are substituted into target relationship data to obtain the yaw rate, wherein the target relationship data is obtained by fitting a plurality of candidate wheel adhesion differences, a plurality of candidate wheel driving force differences and a plurality of candidate yaw rates.

6. The method according to claim 1, characterized in that the controlling the rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting distance of the target vehicle comprises:

Based on the starting driving distance, determining a steering angle correction coefficient, wherein the steering angle correction coefficient is positively correlated with the starting driving distance;

The rear wheels of the target vehicle are controlled to steer at the reference steering angle.

7. The method according to claim 6, characterized in that after controlling the rear wheels of the target vehicle to steer at the reference steering angle, the method further comprises:

Continuously updating the steering angle correction coefficient as the starting driving distance of the target vehicle changes;

Based on the target rear wheel steering angle and the continuously updated steering angle correction coefficient, continuously updating the reference steering angle until the reference steering angle is updated to the target rear wheel steering angle;

The rear wheels of the target vehicle are controlled to steer at a continuously updated reference steering angle.

8. The method according to claim 1, characterized in that after controlling the rear wheels of the target vehicle to steer based on the target rear wheel steering angle and the starting distance of the target vehicle, the method further comprises:

When the starting driving distance of the target vehicle reaches a preset driving distance, or the vehicle speed of the target vehicle reaches a preset vehicle speed, the rear wheels of the target vehicle are no longer controlled to steer based on the target rear wheel steering angle and the starting driving distance of the target vehicle.

9. A vehicle, characterized in that the vehicle comprises:

A memory for storing executable program codes;

A processor is used to call and run the executable program code from the memory, so that the vehicle executes the starting method on a separated road surface as described in any one of claims 1 to 8.