Starting method and vehicle on split road

Abstract

The present application discloses a starting method and vehicle on a separated road surface, and belongs to the field of vehicle technology. Through the technical solution provided in 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

Technical Field

[0001] The present application relates to the field of vehicle technology, and more particularly to a method and a vehicle for starting on a separated road surface in the field of vehicle technology. Background Art

[0002] When driving a vehicle, users will face various working conditions. The vehicle needs to remain stable under different working conditions to ensure that the vehicle has sufficient safety and comfort. Split road refers to the road surface with a large difference in adhesion on both sides. When starting on a split road, the vehicle is prone to slipping, causing the vehicle to sway. Swaying reduces the comfort of the vehicle and poses a safety hazard.

[0003] Therefore, how to smoothly start a vehicle on a separated road surface is a hot topic of research. Summary of the invention

[0004] The embodiments of the present application provide a method and a vehicle for starting on a split road surface, which can improve the safety and comfort of the vehicle when starting on a split road surface. The technical solution is as follows:

[0005] In one aspect, a method for starting on a separated road surface is provided, the method comprising:

[0006] 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;

[0007] 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;

[0008] 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.

[0009] In a possible implementation manner, when the target vehicle starts on a separated road surface, applying a braking force to a target wheel of the target vehicle and determining adhesion of wheels on both sides of the target vehicle includes:

[0010] 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;

[0011] 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.

[0012] In a possible implementation manner, 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 includes:

[0013] 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;

[0014] 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.

[0015] In a possible implementation manner, 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 includes:

[0016] Subtracting the adhesion of the wheels on both sides of the target vehicle to obtain a wheel adhesion difference of the target vehicle;

[0017] Subtracting the driving forces of the wheels on both sides of the target vehicle to obtain a wheel driving force difference of the target vehicle;

[0018] The target rear wheel steering angle is determined based on the wheel adhesion difference and the wheel driving force difference of the target vehicle.

[0019] In a possible implementation manner, determining the target rear wheel steering angle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle includes:

[0020] Determining a yaw rate of the target vehicle based on a wheel adhesion difference and a wheel driving force difference of the target vehicle;

[0021] The rear wheel steering angle corresponding to the yaw angular velocity is determined as the target rear wheel steering angle.

[0022] In a possible implementation manner, 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:

[0023] 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;

[0024] 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.

[0025] In a possible implementation manner, 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 includes:

[0026] 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;

[0027] Multiplying the target rear wheel steering angle by the steering angle correction coefficient to obtain a reference steering angle;

[0028] The rear wheels of the target vehicle are controlled to steer at the reference steering angle.

[0029] In a possible implementation manner, after controlling the rear wheels of the target vehicle to steer at the reference steering angle, the method further includes:

[0030] Continuously updating the steering angle correction coefficient as the starting driving distance of the target vehicle changes;

[0031] 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;

[0032] The rear wheels of the target vehicle are controlled to steer at a continuously updated reference steering angle.

[0033] In a possible implementation manner, 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 includes:

[0034] 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.

[0035] In one aspect, a starting device for a separated road surface is provided, the device comprising:

[0036] an adhesion determination module, for applying a braking force to a target wheel of the target vehicle and determining adhesion of wheels on both sides of the target vehicle when the target vehicle starts on a separated road surface, 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;

[0037] A rear wheel steering angle determination module, used to 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;

[0038] The control module is used to control 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.

[0039] In a possible implementation, the adhesion determination module is used to control the braking system of the target vehicle to apply braking force to the target wheels when the target vehicle starts on a separated road surface; and determine the adhesion of the wheels on both sides of the target vehicle based on the slip rate of the wheels on both sides of the target vehicle.

[0040] In a possible implementation, the adhesion determination module is used to determine the adhesion coefficient of the wheels on both sides of the target vehicle based on the slip rate of the wheels on both sides of the target vehicle; and determine the adhesion 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.

[0041] In one possible implementation, the rear-wheel steering angle determination module is used to subtract the adhesion of the wheels on both sides of the target vehicle to obtain the wheel adhesion difference of the target vehicle; subtract the driving force of the wheels on both sides of the target vehicle to obtain the wheel driving force difference of the target vehicle; and determine the target rear-wheel steering angle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle.

[0042] In a possible implementation, the rear-wheel steering angle determination module is used to determine the yaw angular velocity of the target vehicle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle; and determine the rear-wheel steering angle corresponding to the yaw angular velocity as the target rear-wheel steering angle.

[0043] In a possible implementation, the rear wheel steering angle determination module is used to use the wheel adhesion difference and the wheel driving force difference to query in a target table to obtain the yaw rate, the target table includes multiple candidate yaw rates, and one candidate yaw rate corresponds to a group of candidate wheel adhesion difference and candidate wheel driving force difference; or, substitute 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 multiple candidate wheel adhesion difference values, multiple candidate wheel driving force differences and multiple candidate yaw rates.

[0044] In one possible implementation, the control module is used to determine a steering angle correction coefficient based on the starting driving distance, where the steering angle correction coefficient is positively correlated with the starting driving distance; multiply the target rear wheel steering angle by 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.

[0045] In one possible implementation, the control module is further used to continuously update the steering angle correction coefficient as the starting driving distance of the target vehicle changes; 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 steering of the rear wheels of the target vehicle with the continuously updated reference steering angle.

[0046] In a possible implementation, the control module is further used to control the steering of the rear wheels of the target vehicle no longer based on the target rear wheel steering angle and the starting driving distance of the target vehicle when the starting driving distance of the target vehicle reaches a preset driving distance or the speed of the target vehicle reaches a preset speed.

[0047] On the one hand, a vehicle is provided, comprising one or more processors and one or more memories, wherein the one or more memories store at least one program code, and the program code is loaded and executed by the one or more processors to implement the operations performed by the starting method on a separated road surface.

[0048] On the one hand, a computer-readable storage medium is provided, wherein at least one program code is stored in the computer-readable storage medium, and the program code is loaded and executed by a processor to implement the operations performed by the starting method on a separated road surface.

[0049] 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 through the steering of the rear wheels, thereby improving the safety and comfort of the target vehicle when starting. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a schematic diagram of an implementation environment of a method for starting on a separated road surface provided in an embodiment of the present application;

[0051] Figure 2 is a flow chart of a method for starting on a separated road surface provided in an embodiment of the present application;

[0052] Figure 3 is a flow chart of another method for starting on a separated road surface provided in an embodiment of the present application;

[0053] Figure 4 It is a structural schematic diagram of a separated road starting device provided in an embodiment of the present application;

[0054] Figure 5 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0055] The technical solution in the present application will be described clearly and in detail below in conjunction with the accompanying drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0056] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of technical features reflected. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0057] In order to illustrate the technical solution provided by the embodiments of the present application, some terms involved in the embodiments of the present application are first introduced.

[0058] Separated road surface: a road surface with a large difference in adhesion on both sides. Because of the difference in adhesion on both sides of the vehicle, the vehicle will slide to the side with low adhesion (the side with low adhesion), causing the vehicle body to sway greatly, which can easily cause danger. For example, a road surface composed of ice and concrete is a separated road surface. One side of the vehicle is on the ice and the other side is on the concrete. Since the adhesion of the ice is small and the adhesion of the concrete is large, the vehicle will sway to the ice side when starting.

[0059] Differential: The differential is a device that allows the left and right wheels to rotate at different speeds. It is especially important when the car is turning. When the car is driving in a straight line, the left and right wheels rotate at the same speed, and the differential does not work; but when turning, the inner and outer wheels rotate at different speeds, and the differential allows the wheels to rotate at different speeds, keeping the wheels rolling, reducing wheel wear, and improving driving safety.

[0060] Open differential: Also known as open differential, it is a common type of automotive differential. It allows the two drive wheels to rotate at different speeds when the car turns to meet the needs of turning. When driving in a straight line, the drive wheels on both sides rotate at the same speed, and the gears in the differential rotate at the same speed; when turning, the inner and outer wheels rotate at different speeds, and the gears inside the differential will rotate to balance the speed difference between the wheels, so that the car can turn smoothly.

[0061] Slip rate: It is a parameter that describes the relative motion between the wheels and the road surface. It is used to measure the relative sliding between the wheel footprint and the road surface when the wheel brakes or accelerates while driving in a straight line. A slip rate of 0% means that the distance traveled by the car is equal to the distance traveled by the tire tread, while a slip rate of 100% means that the wheel does not push the car forward.

[0062] Adhesion coefficient: Adhesion coefficient is an important indicator to measure the friction between the wheel and the road surface. It reflects the adhesion ability of the vehicle's wheels under specific road conditions. The size of the adhesion coefficient directly affects the vehicle's acceleration, braking and cornering performance, as well as driving safety under complex weather conditions. The adhesion coefficient is a dimensionless ratio, usually expressed as the ratio of the wheel's tangential force to the normal force.

[0063] Yaw angular velocity: It describes the speed at which a vehicle rotates around a vertical axis during motion and is one of the important parameters for measuring the dynamic stability of a vehicle.

[0064] Rear-wheel steering: A vehicle feature that allows the rear wheels of a vehicle to steer independently of the front wheels, thereby improving the vehicle's handling and stability. Compared with traditional front-wheel steering, rear-wheel steering can provide a more flexible and safer driving experience in different driving conditions, such as high-speed driving and emergency evasive situations.

[0065] In the related technology, the vehicle is usually equipped with a starting differential. When the vehicle starts on a separated road, because one side is a low-adhesion road surface and the other side is a high-adhesion road surface, according to the principle of an open differential, the speed of the low-adhesion side wheel will increase rapidly and the wheel will slip. At this time, the high-adhesion side wheel loses driving force due to the slipping of the low-adhesion side wheel, and the high-adhesion side wheel is almost stationary, resulting in the vehicle being unable to start normally.

[0066] At this time, if the high-addition side wheels and the low-addition side wheels are braked differentially, that is, the low-addition side wheels are braked, then according to the principle of the starting differential (differential but not torque differential), the high-addition side wheels will obtain rotational speed and driving force, so that the vehicle can start. However, this will cause severe sway of the vehicle. After adopting the technical solution provided in the embodiment of the present application, the sway of the vehicle when starting on a separated road surface can be alleviated, thereby improving the safety and comfort of the vehicle.

[0067] After introducing the terms involved in the embodiments of the present application, the implementation environment of the embodiments of the present application is introduced below. Figure 1 The implementation environment of the starting method on a separated road surface provided in the embodiment of the present application includes a vehicle-mounted terminal 101, a brake controller 102 and a rear-wheel steering controller 103.

[0068] The vehicle-mounted terminal 101 is a terminal installed on the vehicle, and has the ability to collect and process data. The vehicle-mounted terminal 101 is connected to multiple component controllers and multiple sensors of the vehicle by wired means. The vehicle-mounted terminal 101 can control multiple component controllers of the vehicle, and different component controllers can control different vehicle components. The sensors can collect information related to the driving of the vehicle. In the embodiment of the present application, information related to the wheels and the road surface can be collected. In the embodiment of the present application, the multiple component controllers include a brake controller 102 and a rear-wheel steering controller 103. The brake controller 102 is used to perform independent brake control on different wheels of the vehicle, and the rear-wheel steering controller 103 is used to control the steering of the rear wheels of the vehicle, that is, to control the steering angle of the rear wheels of the vehicle.

[0069] After introducing the implementation environment of the embodiment of the present application, the application scenario of the technical solution provided by the embodiment of the present application is introduced below. The technical solution provided by the embodiment of the present application can be applied to various vehicles equipped with a differential and capable of rear-wheel steering. For example, the technical solution provided by the embodiment of the present application can be applied to electric vehicles, hybrid vehicles, and fuel vehicles, and the embodiment of the present application does not limit this.

[0070] When the technical solution provided in the embodiment of the present application is applied to an electric vehicle, in response to recognizing that the electric vehicle starts on a separated road surface, a braking force is applied to the wheels of the electric vehicle on the low-attachment road surface (low-attachment side wheels) and the adhesion of the wheels on both sides of the electric 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 electric vehicle, the target rear wheel steering angle of the electric vehicle is determined, and the target rear wheel steering angle is used to reduce the sway of the target vehicle when starting. Based on the target rear wheel steering angle and the starting driving distance of the electric vehicle, the rear wheels of the electric vehicle are controlled to steer, thereby offsetting the sway of the electric vehicle through the steering of the rear wheels, thereby improving the safety and comfort of the electric vehicle when starting.

[0071] It should be noted that the above is explained using the example of the application of the technical solution provided in the embodiment of the present application to an electric vehicle. When the technical solution provided in the embodiment of the present application is applied to other types of vehicles, the implementation process belongs to the same inventive concept as described above and will not be repeated here.

[0072] In addition, the technical solution provided in the embodiments of the present application can be applied to other types of vehicles in addition to the above-mentioned types of vehicles, and the embodiments of the present application are not limited to this.

[0073] After introducing the implementation environment and application scenarios of the embodiments of the present application, the technical solutions provided by the embodiments of the present application are introduced below. Figure 2 Taking the execution subject as a vehicle-mounted terminal as an example, the method includes the following steps.

[0074] 201. When a target vehicle starts on a separated road surface, the on-board terminal applies braking force to a target wheel of the target vehicle and determines the adhesion of wheels on both sides of the target vehicle. The separated road surface includes a low-adhesion road surface and a high-adhesion road surface. The wheels on both sides include a wheel located on the low-adhesion road surface and a wheel located on the high-adhesion road surface. The target wheel is a wheel located on the low-adhesion road surface.

[0075] The target vehicle is a vehicle equipped with an open differential and rear-wheel steering. Separated roads include low-adhesion roads and high-adhesion roads. The adhesion of the wheels on low-adhesion roads is significantly lower than that on high-adhesion roads. Therefore, when the target vehicle starts on a separated road, the adhesion of the wheels on both sides of the target vehicle is quite different. Braking the target wheels on the low-adhesion road can allow the wheels on the high-adhesion road to obtain rotation speed and driving force, so that the target vehicle can start. The adhesion of the wheel can indicate the adhesion ability of the wheel on the road surface. The adhesion is actually the friction between the wheel and the road surface. The greater the adhesion of the wheel, the less likely the wheel is to slip; the smaller the adhesion of the wheel, the easier the wheel is to slip.

[0076] 202. The vehicle-mounted terminal determines 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, and the target rear wheel steering angle is used to reduce the yaw of the target vehicle when starting.

[0077] The driving force of the wheel refers to the power allocated to the wheel 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. In the embodiment of the present application, the target rear wheel steering angle is also called the rear wheel steering feedforward angle. The principle of the rear wheel steering to reduce the yaw of the target vehicle when starting is to use the rear wheel steering to change the driving direction of the target vehicle, and this driving direction is opposite to the yaw direction of the target vehicle, thereby offsetting the yaw of the target vehicle.

[0078] 203. The vehicle-mounted terminal controls 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.

[0079] The starting driving distance of the target vehicle is the cumulative driving distance of the target vehicle after starting this time.

[0080] 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 through the steering of the rear wheels, thereby improving the safety and comfort of the target vehicle when starting.

[0081] It should be noted that the above steps 201-203 are a simple description of the starting method for a separated road surface provided in the embodiment of the present application. The starting method for a separated road surface provided in the embodiment of the present application will be described in more detail below with reference to some examples. Figure 3 Taking the execution subject as a vehicle-mounted terminal as an example, the method includes the following steps.

[0082] 301. In response to a target vehicle starting to start, the vehicle-mounted terminal determines whether 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.

[0083] The target vehicle is a vehicle equipped with an open differential and rear-wheel steering. Separated roads include low-adhesion roads and high-adhesion roads. The adhesion of the wheels on low-adhesion roads is significantly lower than that on high-adhesion roads. Therefore, when the target vehicle starts on a separated road, the adhesion of the wheels on both sides of the target vehicle is quite different. For example, the separated road includes ice and cement roads. The ice is a low-adhesion road, and the cement is a high-adhesion road. The target vehicle starts to start refers to the process of the target vehicle changing from a parking state to a driving state, that is, the process of the power source of the target vehicle changing from no power output to starting to output power.

[0084] In a possible implementation, in response to the target vehicle starting to start, the vehicle-mounted terminal determines the slip rates of the wheels on both sides of the target vehicle. Based on the slip rates of the wheels on both sides, the vehicle-mounted terminal determines whether the target vehicle starts on a separated road surface.

[0085] The wheels on both sides include the left wheel and the right wheel. The slip rate can be used to indicate the relative motion between the wheel and the road surface, that is, the sliding condition. The slip rate of the wheel is related to the adhesion between the wheel and the road surface. Therefore, the slip rate of the wheel can reflect the adhesion of the wheel, and thus reflect whether the target vehicle starts on a separated road surface.

[0086] In this implementation manner, in response to the target vehicle starting to start, the slip rates of the wheels on both sides of the target vehicle can be used to directly determine whether the target vehicle starts on a separated road surface, which is highly efficient.

[0087] For example, in response to the target vehicle starting to start, the vehicle terminal obtains the speed of the target vehicle and the linear speed of the wheels on both sides. The vehicle terminal determines the slip rate of the wheels on both sides of the target vehicle based on the speed of the target vehicle and the linear speed of the wheels on both sides. The vehicle terminal determines whether the target vehicle starts on a separated road based on the difference between the slip rates of the wheels on both sides.

[0088] For example, in response to the target vehicle starting to start, the vehicle terminal obtains the speed of the target vehicle and the angular velocity of the wheels on both sides. The vehicle terminal multiplies the angular velocity of the wheels on both sides by the corresponding wheel radius to obtain the linear velocity of the wheels on both sides. For any wheel on both sides, the vehicle terminal subtracts the speed of the target vehicle from the linear velocity of the wheel and then divides the speed by the speed to obtain the slip rate of the wheel. When the difference between the slip rates of the wheels on both sides is greater than or equal to the difference threshold, the vehicle terminal determines that the target vehicle starts on a separated road surface; when the difference between the slip rates of the wheels on both sides is less than the difference threshold, the vehicle terminal determines that the target vehicle does not start on a separated road surface.

[0089] Among them, the difference threshold is set by technical personnel according to actual conditions, and the embodiments of the present application do not limit this.

[0090] Another implementation of the above step 301 is described below.

[0091] In a possible implementation, in response to the target vehicle starting to move, the vehicle-mounted terminal acquires a road surface image in the driving direction of the target vehicle, and determines whether the target vehicle starts on a separated road surface based on the road surface image.

[0092] The road surface image is an image collected by a camera in front of the target vehicle. Since the surface characteristics of low-adhesion roads and high-adhesion roads are different, the road surface image can be used to distinguish low-adhesion roads from high-adhesion roads, thereby realizing the recognition of separated roads.

[0093] In this implementation, the road surface image in the driving direction is used to determine whether the target vehicle starts on a separated road surface, which is more efficient.

[0094] For example, in response to the target vehicle starting to start, the vehicle-mounted terminal obtains a road surface image in the driving direction of the target vehicle. The vehicle-mounted terminal extracts features from the road surface image to obtain image features of the road surface image. Based on the image features of the road surface image, the vehicle-mounted terminal determines whether the target vehicle starts on a separated road surface.

[0095] For example, in response to the target vehicle starting to start, the vehicle-mounted terminal obtains a road surface image in the driving direction of the target vehicle. The vehicle-mounted terminal inputs the road surface image into the road surface recognition model, and performs multiple convolutions on the road surface image through the road surface recognition model to obtain the image features of the road surface image. The vehicle-mounted terminal uses the road surface recognition model to fully connect and normalize the image features of the road surface image to obtain the road surface type classification value of the road surface image. When the road surface type classification value is greater than or equal to the classification value threshold, the vehicle-mounted terminal determines that the target vehicle starts on a separated road surface; when the road surface type classification value is less than the classification value threshold, the vehicle-mounted terminal determines that the target vehicle does not start on a separated road surface.

[0096] The road surface recognition model is trained based on multiple sample road surface images and the annotated road surface start type corresponding to each sample road surface image, and the annotated road surface start type is starting on a separated road surface or not starting on a separated road surface. The classification value threshold is set by a technician according to actual conditions, and the embodiment of the present application does not limit this. In some embodiments, the road surface recognition model is a binary classification model.

[0097] 302. When the target vehicle starts on a separated road surface, the on-board terminal applies braking force to the target wheel of the target vehicle and determines the adhesion of the wheels on both sides of the target vehicle, the wheels on both sides include wheels located on a low-adhesion road surface and wheels located on a high-adhesion road surface, and the target wheel is a wheel located on the low-adhesion road surface.

[0098] Among them, when the target vehicle starts on a separated road, due to the different adhesion of the wheels on both sides of the target vehicle, the wheel on the high-adhesion side generates a counterclockwise torque around the center of mass of the target vehicle, and this torque causes the target vehicle to yaw. Braking the target wheel on the low-adhesion road can allow the wheel on the high-adhesion road to obtain rotation speed and driving force, so that the target vehicle can start. The adhesion of the wheel can indicate the adhesion ability of the wheel on the road. Adhesion is actually the friction between the wheel and the road. The greater the adhesion of the wheel, the less likely the wheel is to slip. The smaller the adhesion of the wheel, the easier it is for the wheel to slip.

[0099] In a possible implementation, when the target vehicle starts on a separated road, the vehicle terminal controls the braking system of the target vehicle to apply braking force to the target wheel. The vehicle terminal determines the adhesion of the wheels on both sides of the target vehicle based on the slip rate of the wheels on both sides of the target vehicle.

[0100] Among them, the braking system is used to brake the target vehicle, that is, to apply braking force to the wheels of the target vehicle. The braking system includes a braking controller. After the on-board terminal sends a braking control instruction to the braking controller, the braking controller can execute the braking control instruction, that is, control other components in the braking controller to execute the action corresponding to the braking control instruction. Since the target vehicle is equipped with an open differential, after the braking force is applied to the wheels on the low-adhesion road surface, according to the principle of the open differential (differential speed does not differ in torque), the wheels on the high-adhesion road surface can obtain the speed and driving force, so that the target vehicle can start. The slip rate of the wheel is closely related to the adhesion of the wheel. Therefore, the adhesion of the wheel can be determined by using the slip rate of the wheel. It should be noted that the adhesion of the wheel refers to the adhesion between the wheel and the road surface.

[0101] In this embodiment, when the target vehicle starts on a separated road surface, the braking system is controlled to apply braking force to the wheels on the low-adhesion road surface, so that the target vehicle can start with the adhesion of the wheels on the high-adhesion road surface. 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 adhesion determination efficiency is relatively high.

[0102] In order to explain the above implementation more clearly, the above implementation will be explained in several parts below.

[0103] Part 1: When the target vehicle starts on a separated road surface, the vehicle-mounted terminal controls the braking system of the target vehicle to apply braking force to the target wheel.

[0104] In a possible implementation, when the target vehicle starts on a separated road surface, the vehicle-mounted terminal determines the target wheel located on the low-adhesion road surface from the wheels on both sides. The vehicle-mounted terminal sends a braking control instruction to a braking controller of the braking system, the braking control instruction carries the wheel identification of the target wheel, and the braking control instruction is used to instruct to apply braking force to the target wheel. Based on the braking control instruction, the braking controller controls the braking assembly corresponding to the target wheel in the braking system to apply braking force to the target wheel.

[0105] Part 2: The vehicle-mounted terminal determines 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.

[0106] In a possible implementation, the vehicle terminal determines the adhesion coefficient of the wheels on both sides of the target vehicle based on the slip rate of the wheels on both sides of the target vehicle. The vehicle terminal determines the adhesion 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.

[0107] The pressure applied by the target vehicle to the separated road surface is a component force of the target vehicle in a direction perpendicular to the separated road surface.

[0108] In this implementation, the slip rate 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 of the wheels on both sides, and the determination of the adhesion is more accurate.

[0109] For example, the vehicle terminal uses the slip rate of the wheels on both sides of the target vehicle to query the slip rate-adhesion coefficient curve of the target vehicle to obtain the adhesion coefficient of the wheels on both sides. The vehicle terminal multiplies the pressure applied by the target vehicle to the separated road surface by the adhesion coefficient of the wheels on both sides of the target vehicle to obtain the adhesion of the wheels on both sides of the target vehicle.

[0110] Among them, the slip rate-adhesion coefficient curve is obtained by technicians through actual vehicle calibration or simulation of the target vehicle. The slip rate-adhesion coefficient curve can reflect the corresponding relationship between the slip rate and adhesion coefficient of the target vehicle. The slip rate-adhesion coefficient curve can be used to quickly query the adhesion coefficient corresponding to a certain slip rate.

[0111] For example, the vehicle terminal uses the slip rate of the wheels on both sides of the target vehicle to query the slip rate-adhesion coefficient curve of the target vehicle to obtain the adhesion coefficient of the wheels on both sides. The vehicle terminal determines the pressure applied by the target vehicle to the separated road surface based on the mass of the target vehicle and the angle between the separated road surface where the target vehicle is located and the horizontal plane. The vehicle terminal multiplies the pressure applied by the target vehicle to the separated road surface by the adhesion coefficient of the wheels on both sides of the target vehicle to obtain the adhesion of the wheels on both sides of the target vehicle.

[0112] The angle between the separated road surface where the target vehicle is located and the horizontal plane is determined by a gyroscope or a level meter of the target vehicle, which is not limited in this embodiment of the present application.

[0113] Another implementation of the second part is described below.

[0114] In a possible implementation, the vehicle-mounted terminal inputs the slip rate of the wheels on both sides of the target vehicle and the mass of the target vehicle into an adhesion prediction model, processes the slip rate of the wheels on both sides and the mass of the target vehicle through the adhesion prediction model, and outputs the adhesion of the wheels on both sides of the target vehicle.

[0115] The adhesion prediction model is obtained based on a plurality of first sample data and the labeled adhesion training corresponding to each first sample data, and has the ability to predict adhesion, and a first sample data includes a set of sample slip rate and sample quality. In some embodiments, the adhesion prediction model is a regression model.

[0116] In the above implementation mode, the adhesion prediction model is used to determine the adhesion of the wheels on both sides of the target vehicle, which is more efficient.

[0117] For example, the vehicle terminal inputs the slip rate of the wheels on both sides of the target vehicle and the mass of the target vehicle into the adhesion prediction model, and extracts the features of the slip rate of the wheels on both sides and the mass of the target vehicle through the adhesion prediction model to obtain the adhesion prediction features. The vehicle terminal maps the adhesion prediction features through the adhesion prediction model to obtain the adhesion of the wheels on both sides of the target vehicle.

[0118] For example, the vehicle terminal inputs the slip rate of the wheels on both sides of the target vehicle and the mass of the target vehicle into the adhesion prediction model, and performs multiple full connections on the slip rate of the wheels on both sides and the mass of the target vehicle through the adhesion prediction model to obtain the adhesion prediction feature. The vehicle terminal uses the adhesion prediction model to fully connect and normalize the adhesion prediction feature to obtain the adhesion of the wheels on both sides of the target vehicle.

[0119] 303. The vehicle-mounted terminal determines 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, and the target rear wheel steering angle is used to reduce the yaw of the target vehicle when starting.

[0120] Among them, the driving force of the wheel refers to the power allocated to the wheel 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. In the embodiment of the present application, the target rear wheel steering angle is also called the rear wheel steering feedforward angle. The principle of the rear wheel steering to reduce the yaw of the target vehicle when starting is to use the rear wheel steering to change the driving direction of the target vehicle. This driving direction is opposite to the yaw direction of the target vehicle, thereby offsetting the yaw of the target vehicle. In some embodiments, the driving force of the wheels on both sides is obtained by the vehicle-mounted terminal from the bus signal, and the reliability is relatively high.

[0121] In a possible implementation, the vehicle terminal subtracts the adhesion of the wheels on both sides of the target vehicle to obtain the wheel adhesion difference of the target vehicle. The vehicle terminal subtracts the driving force of the wheels on both sides of the target vehicle to obtain the wheel driving force difference of the target vehicle. The vehicle terminal determines the target rear wheel steering angle based on the wheel adhesion difference and wheel driving force difference of the target vehicle.

[0122] Among them, the wheel adhesion difference is used to represent the difference in adhesion between the wheels on both sides of the target vehicle, and the wheel driving force difference is used to represent the difference in driving force between the wheels on both sides of the target vehicle. The difference in adhesion and driving force between the wheels on both sides will affect the yaw amplitude of the target vehicle. Therefore, the difference in adhesion and driving force between the wheels on both sides can be used to determine the target rear wheel steering angle for reducing the yaw.

[0123] In this implementation, the target rear wheel steering angle is determined by utilizing the adhesion difference and driving force difference of the wheels on both sides of the target vehicle. That is, the target rear wheel steering angle is determined by combining factors that affect the yaw of the target vehicle. The accuracy of the target rear wheel steering angle is high.

[0124] In order to explain the above embodiment more clearly, the method 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 explained below.

[0125] In a possible implementation, the 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, and determines the rear wheel steering angle corresponding to the yaw rate as the target rear wheel steering angle.

[0126] Among them, the yaw rate can indicate the severity of the yaw of the target vehicle, and can also indicate the yaw amplitude of the target vehicle. Generally speaking, the greater the difference in adhesion between the wheels on both sides of the target vehicle and the difference in driving force, the greater the yaw rate of the target vehicle. It should be noted that in the above embodiment, the yaw rate is determined by using the wheel adhesion difference and the wheel driving force difference instead of directly using the rotation sensor and the acceleration sensor to obtain the yaw rate because when the vehicle is traveling at a low speed and the vehicle body is unstable, the credibility of the data measured by the rotation sensor and the acceleration sensor is low.

[0127] In this implementation, the wheel adhesion difference and the wheel driving force difference are used to determine the yaw rate of the target vehicle, and the correspondence between the yaw rate and the rear wheel steering angle is used to determine the target rear wheel steering angle, and the accuracy of the target rear wheel steering angle is relatively high.

[0128] The above implementation is described below through two examples.

[0129] Example 1: The vehicle terminal uses the wheel adhesion difference and the wheel driving force difference to query in a target table to obtain the yaw rate, the target table includes multiple candidate yaw rates, and one candidate yaw rate corresponds to a group of candidate wheel adhesion difference and candidate wheel driving force difference. The vehicle terminal determines the target rear wheel steering angle corresponding to the yaw rate from multiple candidate rear wheel steering angles.

[0130] Example 2: The vehicle terminal substitutes the wheel adhesion difference and the wheel driving force difference into the target relationship data to obtain the yaw rate, and the target relationship data is obtained by fitting multiple candidate wheel adhesion differences, multiple candidate wheel driving force differences, and multiple candidate yaw rates. The vehicle terminal determines the target rear wheel steering angle corresponding to the yaw rate from multiple candidate rear wheel steering angles.

[0131] Another implementation of the above step 303 is described below.

[0132] In a possible implementation, the vehicle-mounted terminal inputs the adhesion and driving force of the wheels on both sides of the target vehicle into a steering angle prediction model, processes the adhesion and driving force of the wheels on both sides through the steering angle prediction model, and obtains the target rear wheel steering angle of the target vehicle.

[0133] The steering angle prediction model is trained based on a plurality of second sample data and the annotated rear wheel steering angles corresponding to each second sample data, and has the ability to determine the rear wheel steering angle. In some embodiments, the steering angle prediction model is a regression model.

[0134] For example, the vehicle terminal inputs the adhesion and driving force of the wheels on both sides of the target vehicle into the steering angle prediction model, extracts the features of the adhesion and driving force of the wheels on both sides through the steering angle prediction model, and obtains the steering angle prediction features. The vehicle terminal maps the steering angle prediction features through the steering angle prediction model to obtain the target rear wheel steering angle of the target vehicle.

[0135] For example, the vehicle terminal inputs the adhesion and driving force of the wheels on both sides of the target vehicle into the steering angle prediction model, and performs multiple full connections on the adhesion and driving force of the wheels on both sides through the steering angle prediction model to obtain the steering angle prediction feature. The vehicle terminal uses the steering angle prediction model to fully connect and normalize the steering angle prediction feature to obtain the target rear wheel steering angle of the target vehicle.

[0136] 304. The vehicle-mounted terminal controls 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.

[0137] The starting driving distance of the target vehicle is the cumulative driving distance of the target vehicle after starting this time.

[0138] In a possible implementation, the vehicle terminal determines a steering angle correction coefficient based on the starting driving distance, and the steering angle correction coefficient is positively correlated with the starting driving distance. The vehicle terminal multiplies the target rear wheel steering angle by the steering angle correction coefficient to obtain a reference steering angle. The vehicle terminal controls the rear wheels of the target vehicle to steer at the reference steering angle.

[0139] Among them, since the slip rate of the wheel calculated from the stationary to the starting stage of the vehicle is limited in accuracy, the starting driving distance is used to determine a steering angle correction coefficient in the above implementation, and the steering angle correction coefficient is used to correct the target rear wheel steering angle, that is, to limit the steering amplitude of the rear wheels within a certain starting driving distance, thereby preventing excessive correction of the vehicle yaw. The value range of the steering angle correction coefficient is greater than 0 and less than or equal to 1.

[0140] For example, the vehicle terminal determines the starting driving distance range to which the starting driving distance belongs. The vehicle terminal determines the steering angle correction coefficient corresponding to the starting driving distance range as the steering angle correction coefficient corresponding to the starting driving distance. The vehicle terminal multiplies the target rear wheel steering angle by the steering angle correction coefficient to obtain a reference steering angle. The vehicle terminal sends a rear wheel steering instruction to the rear wheel steering controller of the target vehicle, and the rear wheel steering instruction carries the reference steering angle, so that the rear wheel steering controller controls the rear wheels of the target vehicle to steer at the reference steering angle based on the rear wheel steering instruction.

[0141] Among them, the corresponding relationship between the starting driving distance range and the steering angle correction coefficient is set by technical personnel according to actual conditions, and the embodiments of the present application do not limit this.

[0142] Optionally, based on the above implementation, the following steps can also be performed.

[0143] In a possible implementation, as the starting driving distance of the target vehicle changes, the vehicle-mounted terminal continuously updates the steering angle correction coefficient. 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 with the continuously updated reference steering angle.

[0144] Under this implementation mode, as the starting driving distance of the target vehicle increases, the steering angle correction coefficient will gradually increase, and thus the calculated reference steering angle will gradually increase until it reaches the target rear wheel steering angle and no longer increases, thereby achieving gradient rear wheel steering control and improving the effect of yaw control on the target vehicle.

[0145] Optionally, after step 304 , the vehicle-mounted terminal can also execute the following step 305 .

[0146] 305. When the starting driving distance of the target vehicle reaches a preset driving distance, or the speed of the target vehicle reaches a preset speed, the vehicle-mounted terminal no longer controls 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.

[0147] The starting driving distance reaching the preset driving distance and the speed of the target vehicle reaching the preset speed indicate that the target vehicle has completed the starting stage, and therefore, there is no need to control the yaw of the target vehicle in the starting stage. The preset driving distance and the preset speed are set by technicians according to actual conditions, and are not limited in the embodiments of the present application.

[0148] All the above optional technical solutions can be arbitrarily combined to form optional embodiments of the present application, which will not be described one by one here.

[0149] 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 through the steering of the rear wheels, thereby improving the safety and comfort of the target vehicle when starting.

[0150] Figure 4 is a schematic diagram of a structure of a starting device for a separated road surface provided in an embodiment of the present application, see Figure 4 The device includes: an adhesion determination module 401, a rear wheel steering angle determination module 402 and a control module 403.

[0151] The adhesion determination module 401 is used to apply a braking force to a target wheel of the target vehicle and determine the adhesion of the wheels on both sides of the target vehicle when the target vehicle starts on a separated road surface, wherein the separated road surface includes a low-adhesion road surface and a high-adhesion road surface, the wheels on both sides include a wheel located on the low-adhesion road surface and a wheel located on the high-adhesion road surface, and the target wheel is a wheel located on the low-adhesion road surface;

[0152] A rear wheel steering angle determination module 402, used to 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, and the target rear wheel steering angle is used to reduce the yaw of the target vehicle when starting;

[0153] The control module 403 is used to control 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.

[0154] In a possible implementation, the adhesion determination module 401 is used to control the braking system of the target vehicle to apply braking force to the target wheel when the target vehicle starts on a separated road surface; and determine the adhesion of the wheels on both sides of the target vehicle based on the slip rate of the wheels on both sides of the target vehicle.

[0155] In a possible implementation, the adhesion determination module 401 is used to determine the adhesion coefficient of the wheels on both sides of the target vehicle based on the slip rate of the wheels on both sides of the target vehicle; and determine the adhesion 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.

[0156] In one possible implementation, the rear-wheel steering angle determination module 402 is used to subtract the adhesion of the wheels on both sides of the target vehicle to obtain the wheel adhesion difference of the target vehicle; subtract the driving force of the wheels on both sides of the target vehicle to obtain the wheel driving force difference of the target vehicle; and determine the target rear-wheel steering angle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle.

[0157] In a possible implementation, the rear wheel steering angle determination module 402 is used to determine the yaw angular velocity of the target vehicle based on the wheel adhesion difference and the wheel driving force difference of the target vehicle; and determine the rear wheel steering angle corresponding to the yaw angular velocity as the target rear wheel steering angle.

[0158] In a possible implementation, the rear wheel steering angle determination module 402 is used to use the wheel adhesion difference and the wheel driving force difference to query in a target table to obtain the yaw rate, the target table includes multiple candidate yaw rates, and one candidate yaw rate corresponds to a group of candidate wheel adhesion difference and candidate wheel driving force difference; or, substitute the wheel adhesion difference and the wheel driving force difference into target relationship data to obtain the yaw rate, the target relationship data is obtained by fitting multiple candidate wheel adhesion difference values, multiple candidate wheel driving force differences and multiple candidate yaw rates.

[0159] In one possible implementation, the control module 403 is used to determine a steering angle correction coefficient based on the starting driving distance, where the steering angle correction coefficient is positively correlated with the starting driving distance; multiply the target rear wheel steering angle by 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.

[0160] In one possible implementation, the control module 403 is also used to continuously update the steering angle correction coefficient as the starting distance of the target vehicle changes; 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 steering of the rear wheels of the target vehicle with the continuously updated reference steering angle.

[0161] In a possible implementation, the control module 403 is also used to control the steering of the rear wheels of the target vehicle no longer based on the target rear wheel steering angle and the starting driving distance of the target vehicle when the starting driving distance of the target vehicle reaches a preset driving distance or the speed of the target vehicle reaches a preset speed.

[0162] It should be noted that: the split road starting device provided in the above embodiment is only illustrated by the division of the above functional modules when the vehicle starts on a split road. In actual application, the above functions can be assigned to different functional modules as needed, 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 split road starting device provided in the above embodiment and the split road starting method embodiment belong to the same concept, and the specific implementation process is detailed in the method embodiment, which will not be repeated here.

[0163] 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 through the steering of the rear wheels, thereby improving the safety and comfort of the target vehicle when starting.

[0164] The embodiment of the present application also provides a vehicle, Figure 5 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application.

[0165] Typically, the vehicle 500 includes: one or more processors 501 and one or more memories 502 .

[0166] The processor 501 may include one or more processing cores, such as a 4-core processor, a 5-core processor, etc. The processor 501 may be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). The processor 501 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 501 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 501 may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning.

[0167] The memory 502 may include one or more computer-readable storage media, which may be non-transitory. The memory 502 may also include a high-speed random access memory and a non-volatile memory, such as one or more disk storage devices and flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in the memory 502 is used to store at least one computer program, which is used to be executed by the processor 501 to implement the starting method on a separated road surface provided in the method embodiment of the present application.

[0168] Those skilled in the art will understand that Figure 5 The structure shown in the figure does not constitute a limitation on the vehicle 500, and the vehicle 500 may include more or less components than those shown in the figure, or combine certain components, or adopt a different arrangement of components.

[0169] In addition, the device provided in the embodiments of the present application may specifically be a chip, a component or a module, and the chip may include a connected processor and a memory; wherein the memory is used to store instructions, and when the processor calls and executes the instructions, the chip can execute a method for starting on a separated road surface provided in the above-mentioned embodiment.

[0170] This embodiment also provides a computer-readable storage medium, in which a computer program code is stored. When the computer program code is executed on a computer, the computer executes the above-mentioned related method steps to implement a method for starting on a separated road surface provided in the above embodiment.

[0171] This embodiment further provides a computer program product. When the computer program product is run on a computer, the computer is caused to execute the above-mentioned related steps to implement a method for starting on a separated road surface provided in the above-mentioned embodiment.

[0172] Among them, the device, computer-readable storage medium, computer program product or chip provided in this embodiment is used to execute the corresponding method provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method provided above, and will not be repeated here.

[0173] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0174] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0175] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on 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 a target wheel of the target vehicle and determining the adhesion of wheels on both sides of the target vehicle includes: 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 the 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 method of 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; Multiplying the target rear wheel steering angle by the steering angle correction coefficient to obtain a reference steering angle; 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 includes: 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 includes: 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.

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