Method and device for controlling steering of vehicle, computer equipment and storage medium

Abstract

The invention relates to the technical field of vehicles, and discloses a method and device for controlling steering of a vehicle, computer equipment and a storage medium, the method comprises the steps that a target stability coefficient of a target steering characteristic of the vehicle is acquired, and the target steering characteristic is a steering characteristic selected by a driver of the vehicle from multiple steering characteristics; according to the target stability coefficient, the target yaw velocity of the vehicle is determined, and the actual yaw velocity of the vehicle is obtained; determining a target additional yawing moment according to the target yawing angular velocity of the vehicle and the actual yawing angular velocity of the vehicle; determining a target wheel end torque of a wheel of the vehicle according to the target additional yaw moment, and applying the target wheel end torque of the wheel to the wheel of the vehicle.

Description

Technical Field

[0001] This application relates to the field of computer technology, and particularly to a method, device, computer device and storage medium for controlling the steering of a vehicle. Background Art

[0002] Sometimes, the driver of a vehicle controls the steering of the vehicle according to the desired steering characteristics. How to meet the need of controlling the steering of the vehicle according to the desired steering characteristics of the driver has become a technical problem to be solved. Summary of the Invention

[0003] In view of this, embodiments of this application provide a method, device, computer device and storage medium for controlling the steering of a vehicle.

[0004] In a first aspect, embodiments of this application provide a method for controlling the steering of a vehicle, the method comprising:

[0005] Obtaining a target stability coefficient of a target steering characteristic of the vehicle, wherein the target steering characteristic is a steering characteristic selected by the driver of the vehicle from multiple steering characteristics;

[0006] Determining a target yaw rate of the vehicle according to the target stability coefficient, and obtaining an actual yaw rate of the vehicle;

[0007] Determining a target additional yaw moment according to the target yaw rate of the vehicle and the actual yaw rate of the vehicle;

[0008] Determining a target wheel-end torque of a wheel of the vehicle according to the target additional yaw moment, and applying the target wheel-end torque to the wheel of the vehicle.

[0009] In a possible implementation, obtaining a target stability coefficient of a target steering characteristic of the vehicle includes:

[0010] When the target steering characteristic is a reference steering characteristic, determining the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the reference steering characteristic;

[0011] When the target steering characteristic is a steering characteristic having a stability coefficient correlation relationship with the reference steering characteristic among multiple steering characteristics, determining the reference stability coefficient of the target steering characteristic according to the reference stability coefficient of the reference steering characteristic and the first gain coefficient of the target steering characteristic, and determining the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic.

[0012] In a possible implementation, it further includes:

[0013] When the vehicle is in a steady-state steering condition, the steering characteristic of the vehicle is the reference steering characteristic, and the self-learning condition is satisfied, the self-learning operation is iteratively performed until the reference stability coefficient of the reference steering characteristic is determined. The self-learning operation includes: determining the stability coefficient for which the self-learning operation is directed, and based on the stability coefficient for which the self-learning operation is directed, determining the theoretical yaw rate of the vehicle for which the self-learning operation is directed, and obtaining the actual yaw rate of the vehicle for which the self-learning operation is directed; when the difference between the actual yaw rate and the theoretical yaw rate of the vehicle for which the self-learning operation is directed is less than the lower difference threshold, the stability coefficient for which the self-learning operation is directed is determined as the reference stability coefficient of the reference steering characteristic.

[0014] In a possible implementation, determining the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic includes:

[0015] Obtaining the driving behavior characteristic information of the vehicle, where the driving behavior characteristic information includes: the actual yaw rate of the vehicle, the steering wheel angular acceleration of the vehicle's steering wheel, and the yaw rate ratio of the vehicle;

[0016] According to the driving behavior characteristic information of the vehicle, determining the second gain coefficient of the target steering characteristic;

[0017] According to the reference stability coefficient of the target steering characteristic and the second gain coefficient, determining the target stability coefficient of the target steering characteristic.

[0018] In a possible implementation, determining the second gain coefficient of the target steering characteristic according to the driving behavior characteristic information of the vehicle includes:

[0019] Obtaining the category related to road risk of the road on which the vehicle is traveling, where the category related to road risk is determined according to the number of vehicles traveling on the road and having a risk of instability during a statistical time period;

[0020] According to the driving behavior characteristic information of the vehicle and the category related to road risk, determining the second gain coefficient of the target steering characteristic.

[0021] In a possible implementation, the target stability coefficient of the target steering characteristic is within the range of the stability coefficient corresponding to the target steering characteristic.

[0022] In a second aspect, an embodiment of the present application provides a device for controlling the steering of a vehicle. The device for controlling the steering of a vehicle includes:

[0023] A target stability coefficient acquisition unit, configured to acquire a target stability coefficient of a target steering characteristic of the vehicle, where the target steering characteristic is a steering characteristic selected by a driver of the vehicle from a plurality of steering characteristics;

[0024] A yaw rate determination unit, configured to determine a target yaw rate of the vehicle according to the target stability coefficient, and acquire an actual yaw rate of the vehicle;

[0025] A target additional yaw moment determination unit, configured to determine a target additional yaw moment according to the target yaw rate of the vehicle and the actual yaw rate of the vehicle;

[0026] A steering control unit, configured to determine a target wheel end torque of a wheel of the vehicle according to the target additional yaw moment, and apply the target wheel end torque to the wheel of the vehicle.

[0027] In a possible implementation manner, the target stability coefficient acquisition unit is further configured to, when the target steering characteristic is a reference steering characteristic, determine the target stability coefficient of the target steering characteristic according to a reference stability coefficient of the reference steering characteristic; when the target steering characteristic is a steering characteristic having a stability coefficient association relationship with the reference steering characteristic among a plurality of steering characteristics, determine the reference stability coefficient of the target steering characteristic according to the reference stability coefficient of the reference steering characteristic and a first gain coefficient of the target steering characteristic, and determine the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic.

[0028] In a possible implementation manner, the device for controlling the steering of the vehicle further includes:

[0029] A self-learning unit, configured to iteratively perform a self-learning operation until a reference stability coefficient of the reference steering characteristic is determined when the vehicle is in a steady-state steering condition, the steering characteristic of the vehicle is the reference steering characteristic, and a self-learning condition is satisfied. The self-learning operation includes: determining a stability coefficient for which the self-learning operation is directed, and determining a theoretical yaw rate of the vehicle for which the self-learning operation is directed according to the stability coefficient for which the self-learning operation is directed, and acquiring an actual yaw rate of the vehicle for which the self-learning operation is directed; when a difference between the actual yaw rate of the vehicle and the theoretical yaw rate is less than a lower difference threshold, determining the stability coefficient for which the self-learning operation is directed as the reference stability coefficient of the reference steering characteristic.

[0030] In a possible implementation, the target stability coefficient acquisition unit is further configured to acquire driving behavior characteristic information of the vehicle, where the driving behavior characteristic information includes: the actual yaw rate of the vehicle, the steering wheel angular acceleration of the steering wheel of the vehicle, and the yaw rate ratio of the vehicle; determine a second gain coefficient of the target steering characteristic according to the driving behavior characteristic information of the vehicle; and determine the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic and the second gain coefficient.

[0031] In a possible implementation, the target stability coefficient acquisition unit is further configured to acquire a road risk-related category of the road on which the vehicle is traveling, where the road risk-related category is determined according to the number of vehicles traveling on the road and having a risk of instability during a statistical time period; and determine a second gain coefficient of the target steering characteristic according to the driving behavior characteristic information of the vehicle and the road risk-related category.

[0032] In a possible implementation, the target stability coefficient of the target steering characteristic is within the stability coefficient range corresponding to the target steering characteristic.

[0033] In a third aspect, an embodiment of the present application provides a computer device, including: a memory and a processor, which are communicatively connected to each other, where the memory stores computer instructions, and the processor executes the computer instructions to execute the method according to the first aspect or any corresponding implementation manner thereof.

[0034] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, on which computer instructions are stored, and the computer instructions are used to cause a computer to execute the method according to the first aspect or any corresponding implementation manner thereof.

[0035] In a fifth aspect, the present invention provides a computer program product, including computer instructions, and the computer instructions are used to cause a computer to execute the method according to the first aspect or any corresponding implementation manner thereof.

[0036] The method for controlling the steering of a vehicle provided by an embodiment of the present application, where the target steering characteristic is the steering characteristic selected by the driver of the vehicle from multiple steering characteristics. The target steering characteristic can be regarded as the steering characteristic desired by the driver of the vehicle. After the driver of the vehicle selects the target steering characteristic, obtain the target stability coefficient of the target steering characteristic of the vehicle, determine the target yaw rate of the vehicle according to the target stability coefficient, and obtain the actual yaw rate of the vehicle; determine the target additional yaw moment according to the target yaw rate and the actual yaw rate of the vehicle; determine the target wheel-end torque of the wheels of the vehicle according to the target additional yaw moment, and apply the target wheel-end torque of the wheels to the wheels of the vehicle. Thus, control the steering of the vehicle according to the target steering characteristic selected by the driver of the vehicle, that is, the steering characteristic desired by the driver of the vehicle. In other words, control the vehicle to steer with the steering characteristic desired by the driver of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0038] Figure 1 is a flowchart of the method for controlling the steering of a vehicle provided by an embodiment of the present application;

[0039] Figure 2 is a flowchart of another method for controlling the steering of a vehicle provided by an embodiment of the present application;

[0040] Figure 3 is a flowchart of an example for determining the reference stability coefficient of the reference steering characteristic through self-learning;

[0041] Figure 4 is a flowchart of an example for determining the second gain coefficient of the target steering characteristic;

[0042] Figure 5 is a schematic diagram of an example of the stability coefficient ranges corresponding to multiple steering characteristics;

[0043] Figure 6 is a flowchart of an example for determining the target additional yaw moment;

[0044] Figure 7 is a schematic diagram of the structure of a computer device provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0046] Reference Figure 1 , which shows a schematic flowchart of a method for controlling the steering of a vehicle provided by an embodiment of the present application.

[0047] In step S101, obtain the target stability coefficient of the target steering characteristic of the vehicle.

[0048] Among them, the target steering characteristic is the steering characteristic selected by the driver of the vehicle from multiple steering characteristics.

[0049] When the driver of the vehicle expects to change the steering characteristic of the vehicle, the target steering characteristic is different from the current steering characteristic of the vehicle.

[0050] When the vehicle is stationary, the driver of the vehicle can select the target steering characteristic from multiple steering characteristics, for example, by selecting the target steering characteristic through a soft switch displayed on the screen of the vehicle.

[0051] It should be noted that the steering characteristic can also be called the steering style.

[0052] In a possible implementation, the multiple steering characteristics include: understeer, neutral steer, oversteer, additional oversteer (i.e., oversteer PLUS), and default steer.

[0053] It should be noted that in the embodiments of the present application, the target stability coefficient of neutral steer can be a preset value. In a possible implementation, the target stability coefficient of neutral steer is 0.

[0054] In a possible implementation, in step S101, when the target steering characteristic is the reference steering characteristic, determine the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the reference steering characteristic; when the target steering characteristic is a steering characteristic having a stability coefficient correlation relationship with the reference steering characteristic among the multiple steering characteristics, the reference stability coefficient of the reference steering characteristic can be multiplied by the first gain coefficient of the target steering characteristic to obtain the target stability coefficient of the target steering characteristic.

[0055] Among them, the first gain coefficient of the steering characteristic having a stability coefficient correlation relationship with the reference steering characteristic is pre-calibrated.

[0056] In the embodiments of the present application, the reference steering characteristic may be preset.

[0057] In a possible implementation, the reference steering characteristic is: default steering.

[0058] In step S101, when the target steering characteristic is the reference steering characteristic, determining the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the reference steering characteristic may be: determining the reference stability coefficient of the reference steering characteristic as the target stability coefficient of the target steering characteristic.

[0059] The first gain coefficients of the steering characteristics among the multiple steering characteristics that have a stability coefficient correlation relationship with the reference steering characteristic are pre-calibrated.

[0060] Among them, the steering characteristics that have a stability coefficient correlation relationship with the reference steering characteristic are: the steering characteristics among the multiple steering characteristics other than the reference steering characteristic.

[0061] It should be noted that in the embodiments of the present application, if the multiple steering characteristics include neutral steering, the reference steering characteristic is the steering characteristic among the multiple steering characteristics other than neutral steering. If the multiple steering characteristics include neutral steering, each steering characteristic among the multiple steering characteristics that is not neutral steering and not the reference steering characteristic has a stability coefficient correlation relationship with the reference steering characteristic.

[0062] As an example, the multiple steering characteristics include: understeer, neutral steering, oversteer, oversteer PLUS, default steering. The reference steering characteristic is default steering, and understeer, neutral steering, oversteer, and oversteer PLUS are all steering characteristics that have a stability coefficient correlation relationship with default steering.

[0063] In the embodiments of the present application, the reference stability coefficient of the reference steering characteristic is determined when the vehicle is in a steady-state steering condition and the steering characteristic of the vehicle is the reference steering characteristic.

[0064] In the embodiments of the present application, any method for determining whether the vehicle is in a steady-state steering condition may be used to determine whether the vehicle is in a steady-state steering condition.

[0065] In a possible implementation, to determine whether a vehicle is in a steady-state steering condition, it is possible to respectively determine whether each of the following conditions for determining whether the vehicle is in a steady-state steering condition is satisfied: the change rate of the wheel angle of the vehicle is less than the wheel angle change rate threshold, the steering wheel angle of the vehicle is greater than the steering wheel angle threshold, the vehicle speed is within the vehicle speed range, the yaw rate ratio of the vehicle is within the yaw rate range, the absolute value of the lateral acceleration of the vehicle is within the lateral acceleration threshold range, the absolute value of the transverse acceleration is within the transverse acceleration range, and the wheel-end torque of the wheels of the vehicle is not greater than the wheel-end torque threshold. When each condition for determining whether the vehicle is in a steady-state steering condition is satisfied, it can be determined that the vehicle is in a steady-state steering condition.

[0066] Among them, the corresponding ranges of the determination conditions for determining whether the vehicle is in a steady-state steering condition are defined by the upper threshold value and the lower threshold value of the corresponding range. The upper threshold value and the lower threshold value of the corresponding range are determined by looking up a table according to the vehicle speed. The thresholds in the determination conditions for determining whether the vehicle is in a steady-state steering condition including the corresponding thresholds are determined by looking up a table according to the vehicle speed.

[0067] The yaw rate ratio (YawRateRatio) of the vehicle is: the ratio of the actual yaw rate of the vehicle to the theoretical yaw rate of the vehicle.

[0068] When calculating the yaw rate ratio of the vehicle, the theoretical yaw rate of the vehicle can be calculated using the Ackermann steering angle model. As an example, when calculating the yaw rate ratio of the vehicle using the Ackermann steering angle model, the theoretical yaw rate of the vehicle is calculated according to the vehicle speed and the steering wheel angle of the vehicle.

[0069] It should be noted that YawRateRatio can be abbreviated as I YRR . The larger the absolute value of (I YRR -1), the greater the deviation between the actual steering performance and the theoretical steering performance of the vehicle.

[0070] In a possible implementation, when the vehicle is in a steady-state steering condition and the steering characteristic of the vehicle is the reference steering characteristic, the reference stability coefficient of the reference steering characteristic can be calculated according to the following formula for calculating the reference stability coefficient of the reference steering characteristic:

[0071]

[0072] Among them, K1 represents the reference stability coefficient of the reference steering characteristic, welDeg represents the front wheel angle of the vehicle, V represents the longitudinal vehicle speed, W represents the actual yaw rate of the vehicle, and L represents the wheelbase of the vehicle. When the vehicle is in a steady-state steering condition and the steering characteristic of the vehicle is the reference steering characteristic, the front wheel angle of the vehicle, the longitudinal vehicle speed of the vehicle, and the actual yaw rate of the vehicle can be obtained. Substitute the obtained front wheel angle of the vehicle, the obtained longitudinal vehicle speed of the vehicle, and the obtained actual yaw rate of the vehicle into the formula for calculating the reference stability coefficient of the reference steering characteristic to obtain the reference stability coefficient of the reference steering characteristic. Among them, the obtained front wheel angle of the vehicle can be understood as: the front wheel angle of the vehicle at the moment when the acquisition of the obtained front wheel angle of the vehicle starts. The obtained longitudinal vehicle speed of the vehicle can be understood as: the longitudinal vehicle speed of the vehicle at the moment when the acquisition of the obtained longitudinal vehicle speed of the vehicle starts. The obtained actual yaw rate of the vehicle can be understood as: the actual yaw rate of the vehicle at the moment when the acquisition of the obtained actual yaw rate of the vehicle starts.

[0073] In step S102, according to the target stability coefficient of the target steering characteristic of the vehicle, determine the target yaw rate of the vehicle and obtain the actual yaw rate of the vehicle.

[0074] It should be noted that steps S102 - S104 are executed during the vehicle steering. The actual yaw rate of the vehicle can specifically refer to the actual yaw rate when the vehicle is steering. The target yaw rate of the vehicle can specifically refer to the target yaw rate when the vehicle is steering.

[0075] In step S102, according to the pre-determined correlation between the stability coefficient and the target yaw rate of the vehicle and the target stability coefficient, obtain the actual yaw rate of the vehicle.

[0076] In a possible implementation, determining the target yaw rate of the vehicle according to the target stability coefficient of the target steering characteristic of the vehicle can be expressed as:

[0077]

[0078] Among them, K v' represents the target stability coefficient indicating the target steering characteristics of the vehicle, V represents the longitudinal vehicle speed, δ represents the front wheel angle of the vehicle, and l represents the wheelbase of the vehicle. When determining the target yaw rate of the vehicle based on the target stability coefficient of the target steering characteristics of the vehicle, the longitudinal vehicle speed and the front wheel angle of the vehicle can be obtained, and the target yaw rate of the vehicle can be determined by using the obtained longitudinal vehicle speed and the obtained front wheel angle of the vehicle. The obtained longitudinal vehicle speed of the vehicle can be understood as: the longitudinal vehicle speed of the vehicle at the moment when starting to determine the target yaw rate of the vehicle based on the target stability coefficient of the target steering characteristics of the vehicle. The obtained front wheel angle of the vehicle can be understood as: the front wheel angle of the vehicle at the moment when starting to determine the target yaw rate of the vehicle based on the target stability coefficient of the target steering characteristics of the vehicle.

[0079] In step S102, the sensor data collected by the vehicle's sensors for determining the actual yaw rate of the vehicle can be obtained, and the actual yaw rate of the vehicle can be determined based on the sensor data for determining the actual yaw rate of the vehicle. Thus, the actual yaw rate of the vehicle is obtained. The actual yaw rate of the vehicle obtained through step S102 can be understood as: the actual yaw rate of the vehicle at the moment when starting to execute step S102.

[0080] As an example, in step S102, the yaw rate output by the vehicle's YAW-G sensor is used as the actual yaw rate of the vehicle.

[0081] In step S103, the target additional yaw moment is determined based on the target yaw rate and the actual yaw rate of the vehicle.

[0082] In step S103, the target additional yaw moment can be determined based on the difference between the target yaw rate and the actual yaw rate of the vehicle and the correlation between the yaw rate difference and the additional yaw moment.

[0083] In a possible implementation, the Proportional Integral Derivative (PID) controller used to determine the target additional yaw moment is utilized to determine the target additional yaw moment based on the difference between the target yaw rate and the actual yaw rate of the vehicle and the correlation between the yaw rate difference and the additional yaw moment. ( Proportional Integral Derivative, abbreviated as PID) controller, determines the target additional yaw moment based on the difference between the target yaw rate and the actual yaw rate of the vehicle and the correlation between the yaw rate difference and the additional yaw moment.

[0084] In step S104, based on the target additional yaw moment, the target wheel end torque of the vehicle's wheels is determined, and the target wheel end torque of the wheels is applied to the vehicle's wheels.

[0085] In the embodiments of the present application, the torque distributed to the wheels of the vehicle determined according to the target additional yaw moment is called the target wheel-end torque of the wheels.

[0086] In step S104, different wheel-end torques are applied between the left and right wheels of the same axle of the vehicle according to the target additional yaw moment.

[0087] In step S104, any algorithm for determining the wheel-end torque distributed to the wheels of the vehicle according to the given additional yaw moment can be used to determine the target wheel-end torque of the wheels of the vehicle according to the target additional yaw moment.

[0088] In a possible implementation manner, the Sequential Quadratic Programming (abbreviated as SQP) algorithm is adopted to determine the target wheel-end torque of each wheel of the vehicle according to the target additional yaw moment.

[0089] In another possible implementation manner, according to the target additional yaw moment, an optimal distribution method is adopted to determine the target wheel-end torque of each wheel of the vehicle. The target wheel-end torque of the left front wheel of the vehicle is determined according to the distribution ratio of the left front wheel of the vehicle and the target additional yaw moment. The target wheel-end torque of the left rear wheel of the vehicle is determined according to the distribution ratio of the left rear wheel of the vehicle and the target additional yaw moment. The target wheel-end torque of the right front wheel of the vehicle is determined according to the distribution ratio of the right front wheel of the vehicle and the target additional yaw moment. The target wheel-end torque of the right rear wheel of the vehicle is determined according to the distribution ratio of the right rear wheel of the vehicle and the target additional yaw moment.

[0090] In step S104, the target wheel-end torque of the wheels is applied to the wheels of the vehicle according to the target additional yaw moment. Thus, the steering of the vehicle is controlled according to the target steering characteristics selected by the driver of the vehicle. That is to say, the vehicle is controlled to steer with the target steering characteristics selected by the driver of the vehicle.

[0091] Reference Figure 2 , which shows a schematic flow chart of another method for controlling the steering of a vehicle provided by the embodiments of the present application.

[0092] In step S201, when the target steering characteristic is the reference steering characteristic, the target stability coefficient of the target steering characteristic is determined according to the reference stability coefficient of the reference steering characteristic; when the target steering characteristic is a steering characteristic having a stability coefficient correlation relationship with the reference steering characteristic among multiple steering characteristics, the reference stability coefficient of the target steering characteristic is determined according to the reference stability coefficient of the reference steering characteristic and the first gain coefficient of the target steering characteristic, and the target stability coefficient of the target steering characteristic is determined according to the reference stability coefficient of the target steering characteristic.

[0093] In a possible implementation, when the target steering characteristic is the reference steering characteristic, the reference stability coefficient of the reference steering characteristic is directly determined as the target stability coefficient of the target steering characteristic.

[0094] In another possible implementation, when the target steering characteristic is the reference steering characteristic, if the reference stability coefficient of the reference steering characteristic is within the stability coefficient range corresponding to the reference steering characteristic, then the reference stability coefficient of the reference steering characteristic is used as the target stability coefficient of the reference steering characteristic. If the reference stability coefficient of the reference steering characteristic is not within the stability coefficient range corresponding to the reference steering characteristic, then the stability coefficient closest to the reference stability coefficient of the reference steering characteristic among the two stability coefficient thresholds that define the stability coefficient range corresponding to the reference steering characteristic is used as the target stability coefficient of the reference steering characteristic.

[0095] The two stability coefficient thresholds that define the stability coefficient range corresponding to the reference steering characteristic are: the upper stability coefficient threshold that defines the stability coefficient range corresponding to the reference steering characteristic, and the lower stability coefficient threshold that defines the stability coefficient range corresponding to the reference steering characteristic. The upper stability coefficient threshold that defines the stability coefficient range corresponding to the reference steering characteristic is greater than the lower stability coefficient threshold that defines the stability coefficient range corresponding to the reference steering characteristic.

[0096] As an example, if the reference stability coefficient of the reference steering characteristic is not less than the lower stability coefficient threshold that defines the stability coefficient range corresponding to the reference steering characteristic and the reference stability coefficient of the reference steering characteristic is not greater than the upper stability coefficient threshold that defines the stability coefficient range corresponding to the reference steering characteristic, then it can be determined that the reference stability coefficient of the reference steering characteristic is within the stability coefficient range corresponding to the reference steering characteristic.

[0097] In a possible implementation, the reference steering characteristic is the default steering.

[0098] It should be noted that the first gain coefficients of the steering characteristics among multiple steering characteristics that have a stability coefficient correlation relationship with the reference steering characteristic are pre-calibrated.

[0099] If multiple steering characteristics include neutral steering, then the reference steering characteristic is the steering characteristic other than neutral steering. If multiple steering characteristics include neutral steering, each steering characteristic that is not the neutral steering characteristic and not the reference steering characteristic among the multiple steering characteristics is a steering characteristic that has a stability coefficient correlation relationship with the reference steering characteristic.

[0100] In a possible implementation, when the target steering characteristic is a steering characteristic among multiple steering characteristics that has a stability coefficient correlation relationship with the reference steering characteristic, the reference stability coefficient of the target steering characteristic based on the reference stability coefficient of the reference steering characteristic and the first gain coefficient of the target steering characteristic may include: multiplying the reference stability coefficient of the reference steering characteristic by the first gain coefficient of the target steering characteristic to obtain the reference stability coefficient of the target steering characteristic.

[0101] In a possible implementation, it further includes: step S200.

[0102] In step S200, when the vehicle is in a steady-state steering condition and the steering characteristic of the vehicle is the reference steering characteristic and the self-learning condition is satisfied, the self-learning operation is iteratively executed until the reference stability coefficient of the reference steering characteristic is determined.

[0103] In other words, once it is detected that the vehicle is in a steady-state steering condition and the steering characteristic of the vehicle is the reference steering characteristic and the self-learning condition is satisfied, the reference stability coefficient of the reference steering characteristic is determined through the self-learning operation. Before determining the reference stability coefficient of the reference steering characteristic, the self-learning operation is iteratively executed.

[0104] The self-learning condition may be: the difference between the actual yaw rate of the vehicle and the theoretical yaw rate of the vehicle is greater than the upper difference threshold. As an example, the upper difference threshold is 0.1 rad / s. To detect whether the difference between the actual yaw rate of the vehicle and the theoretical yaw rate of the vehicle is greater than the upper difference threshold, the actual yaw rate of the vehicle can be obtained. At the same time, the vehicle speed and the steering wheel angle of the vehicle can be obtained, and the theoretical yaw rate of the vehicle can be obtained according to the Ackermann steering angle model based on the obtained vehicle speed and the obtained steering wheel angle of the vehicle.

[0105] It should be noted that the difference between the actual yaw rate of the vehicle and the theoretical yaw rate of the vehicle is: the larger one of the actual yaw rate of the vehicle and the theoretical yaw rate of the vehicle minus the smaller one of the actual yaw rate of the vehicle and the theoretical yaw rate of the vehicle.

[0106] The lower difference threshold is less than the upper difference threshold. As an example, the lower difference threshold is 0.005 rad / s.

[0107] The t-th self-learning operation includes: determining the stability coefficient targeted by the t-th self-learning operation, and based on the stability coefficient targeted by the t-th self-learning operation, determining the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation, and obtaining the actual yaw rate of the vehicle targeted by the t-th self-learning operation; when the difference between the actual yaw rate of the vehicle targeted by the t-th self-learning operation and the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation is less than the lower difference threshold, determining the stability coefficient targeted by the t-th self-learning operation as the reference stability coefficient of the reference steering characteristic.

[0108] In the embodiment of the present application, the actual yaw rate of the vehicle obtained during the t-th self-learning operation is called the actual yaw rate of the vehicle targeted by the t-th self-learning operation.

[0109] It should be noted that if the difference between the actual yaw rate of the vehicle targeted by the t-th self-learning operation and the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation is not less than the lower difference threshold, then the (t + 1)-th self-learning operation is executed.

[0110] Step S200 is used to determine the reference stability coefficient of the reference steering characteristic through self-learning.

[0111] Step S200 takes into account that: as an important control parameter in yaw control, if the stability coefficient is determined by calibration, there may be deviations in the reference stability coefficient of the reference steering characteristic due to tire wear and road factors. During the entire life cycle of vehicle driving, due to the inevitable wear and aging of tires, the cornering stiffness of the vehicle is in a dynamic change process, and due to road factors, the position of the vehicle's center of mass is also likely to change, resulting in deviations in the reference stability coefficient of the reference steering characteristic.

[0112] By determining the reference stability coefficient of the reference steering characteristic through the self-learning method in step S200, it is possible to avoid deviations in the reference stability coefficient of the reference steering characteristic caused by changes in the cornering stiffness of the tire and / or changes in the position of the center of mass, obtain an accurate reference stability coefficient of the reference steering characteristic, and improve the accuracy of the determined additional yaw moment.

[0113] During the t-th self-learning operation, the stability coefficient targeted by the t-th self-learning operation can be determined according to the following formula:

[0114]

[0115] Wherein, K represents the stability coefficient targeted by the t-th self-learning operation, welDeg represents the front wheel angle of the vehicle, V represents the longitudinal vehicle speed, W represents the actual yaw rate of the vehicle, and L represents the wheelbase of the vehicle. During the t-th self-learning operation, the front wheel angle of the vehicle, the longitudinal vehicle speed, and the actual yaw rate of the vehicle can be obtained, and the front wheel angle of the vehicle obtained during the t-th self-learning operation, the longitudinal vehicle speed of the vehicle obtained during the t-th self-learning operation, and the actual yaw rate of the vehicle obtained during the t-th self-learning operation are substituted into the formula for determining the stability coefficient targeted by the t-th self-learning operation to obtain the stability coefficient targeted by the t-th self-learning operation.

[0116] In step S200, according to the stability coefficient targeted by the t-th self-learning operation, the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation is determined.

[0117] In a possible implementation manner, determining the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation according to the stability coefficient targeted by the t-th self-learning operation includes: using the following formula for determining the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation to determine the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation:

[0118]

[0119] Wherein, ω d represents the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation, K represents the stability coefficient targeted by the t-th self-learning operation, μ is the ground adhesion coefficient, g is the gravity coefficient, v represents the longitudinal vehicle speed, sgn represents the sign function, and δ f represents the front wheel angle of the vehicle. Among them, the ground adhesion coefficient is obtained when determining the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation. The front wheel angle of the vehicle used when determining the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation can be the front wheel angle of the vehicle obtained during the above-mentioned t-th self-learning operation. The longitudinal vehicle speed of the vehicle used when determining the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation can be the longitudinal vehicle speed of the vehicle obtained during the above-mentioned t-th self-learning operation.

[0120] Among them, the above formula for determining the theoretical yaw rate of the vehicle targeted by the t-th self-learning operation can be derived based on the vehicle two-degree-of-freedom model.

[0121] The vehicle two-degree-of-freedom model can be expressed as:

[0122]

[0123] where θ is the centroid yaw angle of the vehicle, with the unit of rad; k f and k r are the cornering stiffness of the front axle and the cornering stiffness of the rear axle of the vehicle respectively, with the unit of N / rad, δ f is the front wheel steering angle of the vehicle, and ω1 is the yaw rate. When the vehicle is in steady-state driving, the lateral acceleration of the vehicle will be restricted by the road surface conditions, expressed as:

[0124] uω1 ≤ gμ

[0125] where u is the longitudinal vehicle speed, μ is the ground adhesion coefficient, and g is the gravitational coefficient. The centroid yaw angle θ of the vehicle can be approximated as u / v1, and v1 is the lateral vehicle speed.

[0126] Reference Figure 3 shows a flowchart of an example of determining a reference stability coefficient of a reference steering characteristic through self-learning.

[0127] When the vehicle is in a steady-state steering condition, the steering characteristic of the vehicle is the reference steering characteristic, and the self-learning condition is satisfied, the self-learning of the reference stability coefficient of the reference steering characteristic is triggered. Determine the difference between the actual yaw rate of the vehicle obtained during one self-learning operation and the theoretical yaw rate of the vehicle targeted by one self-learning operation. If the difference is less than the lower difference threshold, the self-learning is successful, and the stability coefficient targeted by one self-learning operation is used as the reference stability coefficient of the reference steering characteristic. If the difference is not less than the lower difference threshold, the next self-learning operation of this self-learning operation is executed.

[0128] In a possible implementation, step S201 includes: step S2011.

[0129] In step S2011, when the target steering characteristic is a steering characteristic among multiple steering characteristics that has a stability coefficient correlation relationship with the reference steering characteristic, obtain the driving behavior characteristic information of the vehicle. The driving behavior characteristic information includes: the actual yaw rate of the vehicle, the steering wheel angular acceleration of the vehicle's steering wheel, and the yaw rate ratio of the vehicle. When the target steering characteristic is a steering characteristic among multiple steering characteristics that has a stability coefficient correlation relationship with the reference steering characteristic, determine the second gain coefficient of the target steering characteristic according to the driving behavior characteristic information of the vehicle. When the target steering characteristic is a steering characteristic among multiple steering characteristics that has a stability coefficient correlation relationship with the reference steering characteristic, determine the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic and the second gain coefficient of the target steering characteristic.

[0130] Step S2011 takes into account: the actual yaw rate of the vehicle, the steering wheel angular acceleration of the vehicle's steering wheel, and the strong correlation between the yaw rate ratio of the vehicle and the steering characteristics. When the target steering characteristic is the steering characteristic having a stability coefficient correlation relationship with the reference steering characteristic among multiple steering characteristics, parameters with strong correlation with the steering characteristics such as the actual yaw rate of the vehicle, the steering wheel angular acceleration of the vehicle's steering wheel, and the yaw rate ratio of the vehicle are involved in the calculation of the target stability coefficient of the target steering characteristic, improving the accuracy of the target stability coefficient of the target steering characteristic.

[0131] In a possible implementation manner of step S2011, the weighted sum of the actual yaw rate of the vehicle, the steering wheel angular acceleration of the vehicle's steering wheel, and the yaw rate ratio of the vehicle can be calculated based on the actual yaw rate of the vehicle, the steering wheel angular acceleration of the vehicle's steering wheel, the yaw rate ratio of the vehicle, the weight coefficient of the actual yaw rate of the vehicle, the weight coefficient of the steering wheel angular acceleration of the vehicle's steering wheel, and the weight coefficient of the yaw rate ratio of the vehicle. The sum of the weight coefficients of the weight coefficient of the actual yaw rate of the vehicle, the weight coefficient of the steering wheel angular acceleration of the vehicle's steering wheel, and the weight coefficient of the yaw rate ratio of the vehicle can be calculated to obtain the sum of the weight coefficients. The weighted sum can be divided by the sum of the weight coefficients to obtain the steering characteristic coefficient of the driving behavior characteristic information of the vehicle. The steering characteristic coefficient of the driving behavior characteristic information of the vehicle is determined as the second gain coefficient of the target steering characteristic.

[0132] As an example, the weight coefficient of each of the actual yaw rate of the vehicle, the steering wheel angular acceleration of the vehicle's steering wheel, and the yaw rate ratio of the vehicle is preset.

[0133] As another example, multiple sample data collected during the steady-state steering of the vehicle can be pre-collected. The sample data includes the actual yaw rate of the vehicle, the steering wheel angular acceleration, and the yaw rate ratio of the vehicle. Based on the multiple sample data, the correlation between the actual yaw rate of the vehicle, the steering wheel angular acceleration, and the yaw rate ratio of the vehicle and the second gain coefficient of the steering characteristic is analyzed to determine the weight coefficients of the actual yaw rate of the vehicle, the steering wheel angular acceleration, and the yaw rate ratio of the vehicle. As an example, a fuzzy logic membership function corresponding to the steering characteristic is designed, and the weight coefficients of the actual yaw rate of the vehicle, the steering wheel angular acceleration, and the yaw rate ratio of the vehicle are determined through the fuzzy logic membership function corresponding to the steering characteristic.

[0134] In another possible implementation of step S2011, obtain the category related to road risk of the road on which the vehicle is traveling, where the category related to road risk of the road on which the vehicle is traveling is determined according to the number of vehicles traveling on the road and having the risk of instability during the statistical time period; determine the second gain coefficient of the target steering characteristic according to the driving behavior characteristic information of the vehicle and the category related to road risk of the road on which the vehicle is traveling.

[0135] In the embodiments of the present application, any method for determining whether the vehicle is in an unstable risk condition can be used to determine whether the vehicle is in an unstable risk condition.

[0136] In a possible implementation, when it is determined that at least one of the following conditions for determining whether the vehicle is in an unstable risk condition is satisfied, it can be determined that the vehicle is in an unstable risk condition: the change rate of the wheel angle of the vehicle is greater than the wheel angle change rate threshold, the yaw angular velocity of the vehicle is greater than the yaw angular velocity threshold, the absolute value of the lateral acceleration of the vehicle is greater than the lateral acceleration absolute value threshold, and the angular velocity of the steering wheel of the vehicle is greater than the steering wheel angular velocity threshold.

[0137] Among them, the threshold in the conditions for determining whether the vehicle is in an unstable risk condition can be determined by looking up a table according to the vehicle speed.

[0138] It should be noted that the threshold in the conditions for determining whether the vehicle is in an unstable risk condition is greater than the threshold of the same threshold type in the conditions for determining whether the vehicle is in a steady-state steering condition.

[0139] In a possible implementation, the statistical time period is the time period between the current time and the target previous time of the current time. The target previous time of the current time is the time before the current time and with a time interval of a preset time interval from the current time.

[0140] In a possible implementation, the category related to road risk of the road on which the vehicle is traveling is determined according to the number of vehicles traveling on the road and having the risk of instability during the statistical time period. The statistical time period can be divided into statistical sub-periods with a preset duration, such as 15 s. If a vehicle is detected to be in an unstable risk condition in each of more than a threshold number of statistical sub-periods, it can be regarded as a vehicle traveling on the road and having the risk of instability during the statistical time period. The more the number of vehicles traveling on the road and having the risk of instability during the statistical time period, the higher the potential for traffic accidents on this road during the statistical time period. The higher the potential for traffic accidents on this road, the more cautious the steering characteristics of the vehicle should be at this time.

[0141] In step S2011, the second gain coefficient of the target steering characteristic can be determined according to the driving behavior characteristic information of the vehicle and the category related to road risk of the road on which the vehicle is traveling. Considered is: the strong correlation between the category related to road risk of the road on which the vehicle is traveling and the steering characteristic. The category related to road risk of the road on which the vehicle is traveling participates in the calculation of the target stability coefficient of the target steering characteristic, improving the accuracy of the target stability coefficient of the target steering characteristic.

[0142] Each category related to road risk corresponds to an out-of-stability risk vehicle quantity interval respectively. The greater the risk indicated by the category related to road risk, the greater the left endpoint value of the out-of-stability risk vehicle quantity interval corresponding to the category related to road risk.

[0143] To determine the category related to road risk of the road on which the vehicle is traveling, determine the out-of-stability risk vehicle quantity interval in which the quantity of vehicles traveling on this road and having out-of-stability risk within the statistical time period is located, and determine the category related to road risk corresponding to the out-of-stability risk vehicle quantity interval in which the quantity of vehicles traveling on this road and having out-of-stability risk within the statistical time period is located as the category related to road risk of the road on which the vehicle is traveling.

[0144] As an example, pre-set categories related to road risk such as safe road category, risky road category, dangerous road category, etc. The risk indicated by the safe road category is less than the risk indicated by the risky road category, and the risk indicated by the risky road category is less than the risk indicated by the dangerous road category.

[0145] Each category related to road risk has a steering characteristic coefficient respectively.

[0146] The smaller the risk indicated by the category related to road risk, the greater the steering characteristic coefficient of the category related to road risk can be.

[0147] As an example, pre-set categories related to road risk such as safe road category, risky road category, dangerous road category, etc. The steering characteristic coefficients of the safe road category, the risky road category, and the dangerous road category are 1, 0.95, and 0.9 respectively.

[0148] In a possible implementation, determining the second gain coefficient of the target steering characteristic according to the driving behavior characteristic information of the vehicle and the category related to road risk of the road on which the vehicle is traveling may include: calculating the weighted sum of the actual yaw rate of the vehicle, the steering wheel angular acceleration of the vehicle's steering wheel, the yaw rate ratio of the vehicle, the weight coefficient of the vehicle's actual yaw rate, the weight coefficient of the vehicle's steering wheel angular acceleration, and the weight coefficient of the vehicle's yaw rate ratio. The sum of the weight coefficients of the vehicle's actual yaw rate, the weight coefficient of the vehicle's steering wheel angular acceleration, and the weight coefficient of the vehicle's yaw rate ratio can be calculated to obtain the sum of the weight coefficients. The weighted sum can be divided by the sum of the weight coefficients to obtain the steering characteristic coefficient of the vehicle's driving behavior characteristic information. The steering characteristic coefficient of the vehicle's driving behavior characteristic information is multiplied by the steering characteristic coefficient of the category related to road risk of the road on which the vehicle is traveling to obtain the second gain coefficient of the target steering characteristic.

[0149] Among them, determining the second gain coefficient of the target steering characteristic according to the driving behavior characteristic information of the vehicle and the category related to road risk of the road on which the vehicle is traveling can be expressed as:

[0150]

[0151] Among them, I a represents the second gain coefficient of the target steering characteristic, I r represents the steering characteristic coefficient of the category related to road risk of the road on which the vehicle is traveling, ω represents the actual yaw rate of the vehicle, δ s represents the steering wheel angle of the vehicle's steering wheel, represents the steering wheel angular acceleration of the vehicle's steering wheel, I YRR represents the yaw rate ratio of the vehicle, and A, B, and C respectively represent the weight coefficient of the vehicle's actual yaw rate, the weight coefficient of the vehicle's steering wheel angular acceleration, and the weight coefficient of the vehicle's yaw rate ratio.

[0152] Reference Figure 4 , which shows a flowchart of an example for determining the second gain coefficient of the target steering characteristic.

[0153] In this example, according to the actual yaw rate of the vehicle, the angular acceleration of the steering wheel of the vehicle, and the yaw rate ratio of the vehicle, the steering characteristic coefficient of the driving behavior characteristic information of the vehicle is determined. According to the number of vehicles driving on the road and having a risk of instability during the statistical time period, the category related to road risk of the road on which the vehicle is driving is determined. The steering characteristic coefficient of the category related to road risk of the road on which the vehicle is driving is determined. According to the steering characteristic coefficient of the driving behavior characteristic information of the vehicle and the steering characteristic coefficient of the category related to road risk of the road on which the vehicle is driving, the second gain coefficient of the target steering characteristic is determined.

[0154] In a possible implementation manner, in step S2011, when the target steering characteristic is the steering characteristic having a stability coefficient correlation relationship with the reference steering characteristic among multiple steering characteristics, determining the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic and the second gain coefficient of the target steering characteristic includes: determining the candidate stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic and the second gain coefficient of the target steering characteristic; determining the target stability coefficient of the target steering characteristic according to the candidate stability coefficient of the target steering characteristic.

[0155] When determining the candidate stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic and the second gain coefficient of the target steering characteristic, the sum of the reference stability coefficient of the target steering characteristic and the second gain coefficient of the target steering characteristic can be determined as the candidate stability coefficient of the target steering characteristic.

[0156] Determining the candidate stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic and the second gain coefficient of the target steering characteristic can be expressed as:

[0157] K v =K v1 +I a

[0158] Wherein, K v represents the candidate stability coefficient of the target steering characteristic, K v1 represents the reference stability coefficient of the target steering characteristic, and I a represents the second gain coefficient of the target steering characteristic.

[0159] In a possible implementation manner, in step S2011, when the target steering characteristic is the steering characteristic having a stability coefficient correlation relationship with the reference steering characteristic among multiple steering characteristics, directly use the candidate stability coefficient of the target steering characteristic as the target stability coefficient of the target steering characteristic.

[0160] In another possible implementation, in step S2011, when the target steering characteristic is a steering characteristic among multiple steering characteristics that has a stability coefficient correlation relationship with the reference steering characteristic, the target stability coefficient of the target steering characteristic is within the stability coefficient range corresponding to the target steering characteristic. If the candidate stability coefficient of the target steering characteristic is within the stability coefficient range corresponding to the target steering characteristic, then the candidate stability coefficient of the target steering characteristic is used as the target stability coefficient of the target steering characteristic. If the candidate stability coefficient of the target steering characteristic is not within the stability coefficient range corresponding to the target steering characteristic, then the stability coefficient closest to the candidate stability coefficient of the target steering characteristic among the two stability coefficient thresholds that define the stability coefficient range corresponding to the target steering characteristic is used as the target stability coefficient of the target steering characteristic.

[0161] Among them, the two stability coefficient thresholds that define the stability coefficient range corresponding to the target steering characteristic are: the upper stability coefficient threshold that defines the stability coefficient range corresponding to the target steering characteristic, and the lower stability coefficient threshold that defines the stability coefficient range corresponding to the target steering characteristic. The upper stability coefficient threshold that defines the stability coefficient range corresponding to the target steering characteristic is greater than the lower stability coefficient threshold that defines the stability coefficient range corresponding to the target steering characteristic.

[0162] As an example, if the candidate stability coefficient of the target steering characteristic is not less than the lower stability coefficient threshold that defines the stability coefficient range corresponding to the target steering characteristic and the candidate stability coefficient of the target steering characteristic is not greater than the upper stability coefficient threshold that defines the stability coefficient range corresponding to the target steering characteristic, then it can be determined that the candidate stability coefficient of the target steering characteristic is within the stability coefficient range corresponding to the target steering characteristic.

[0163] Reference Figure 5 , which shows a schematic diagram of an example of the stability coefficient ranges corresponding to multiple steering characteristics.

[0164] The target stability coefficient of neutral steering is 0. Figure 5 Shows the stability coefficient range corresponding to understeer, the stability coefficient range corresponding to oversteer, and the stability coefficient range corresponding to oversteer PLUS.

[0165] In the embodiments of the present application, the target stability coefficient of the target steering characteristic is within the stability coefficient range corresponding to the target steering characteristic. Thus, it can be ensured that the positivity or negativity of the target stability coefficient of the target steering characteristic does not coincide with the positivity or negativity of the stability coefficient of the target steering characteristic determined based on prior experience. The target stability coefficient of the target steering characteristic being within the stability coefficient range corresponding to the target steering characteristic can maintain the road feel of the driver of the vehicle and avoid the driving risks that may be caused by excessive changes in steering characteristics.

[0166] In step S202, based on the target stability coefficient of the target steering characteristics of the vehicle, determine the target yaw rate of the vehicle and obtain the actual yaw rate of the vehicle.

[0167] The process of step S202 refers to the process of step S102.

[0168] In step S203, based on the target yaw rate of the vehicle and the actual yaw rate of the vehicle, determine the target additional yaw moment.

[0169] The process of step S203 refers to the process of step S103.

[0170] Reference Figure 6 , which shows a flowchart of an example for determining the target additional yaw moment.

[0171] In this example, the reference steering characteristic is the default steering. The driver of the vehicle selects the target steering characteristic, i.e., understeering.

[0172] In this example, based on parameters such as the vehicle speed, the actual yaw rate of the vehicle, the steering wheel angular acceleration of the vehicle's steering wheel, and the category related to road risk of the road on which the vehicle is traveling, determine the first gain coefficient of understeering and the second gain coefficient of understeering. In this example, based on the first gain coefficient of understeering, the second gain coefficient of understeering, and the reference stability coefficient of the reference steering characteristic of the default steering, calculate the target stability coefficient of understeering.

[0173] Among them, calculating the target stability coefficient of understeering based on the first gain coefficient of understeering, the second gain coefficient of understeering, and the reference stability coefficient of the reference steering characteristic of the default steering may include: multiplying the reference stability coefficient of the default steering by the first gain coefficient of understeering to obtain the reference stability coefficient of understeering; based on the reference stability coefficient of understeering and the second gain coefficient of understeering, determine the target stability coefficient of understeering.

[0174] In this example, based on the target stability coefficient of understeering, calculate the target additional yaw moment for controlling the vehicle to steer with understeering.

[0175] In step S204, based on the target additional yaw moment, determine the target wheel end torque of the vehicle's wheels and apply the target wheel end torque to the vehicle's wheels.

[0176] The process of step S204 refers to the process of step S104.

[0177] An embodiment of the present application provides a device for controlling the steering of a vehicle. The device for controlling the steering of the vehicle is installed on the vehicle, and this device is used to implement the above-mentioned embodiments and preferred implementation manners, and those that have been described will not be repeated. As used hereinafter, the term "unit" can be a combination of software and / or hardware that can achieve a predetermined function. Although the systems described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware is also possible and contemplated.

[0178] The device for controlling the steering of a vehicle includes:

[0179] A target stability coefficient acquisition unit, configured to acquire a target stability coefficient of the target steering characteristic of the vehicle, where the target steering characteristic is the steering characteristic selected by the driver of the vehicle from multiple steering characteristics;

[0180] A yaw rate determination unit, configured to determine a target yaw rate of the vehicle according to the target stability coefficient, and acquire an actual yaw rate of the vehicle;

[0181] A target additional yaw moment determination unit, configured to determine a target additional yaw moment according to the target yaw rate of the vehicle and the actual yaw rate of the vehicle;

[0182] A steering control unit, configured to determine a target wheel-end torque of the wheels of the vehicle according to the target additional yaw moment, and apply the target wheel-end torque to the wheels of the vehicle.

[0183] In a possible implementation manner, the target stability coefficient acquisition unit is further configured to, when the target steering characteristic is the reference steering characteristic, determine the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the reference steering characteristic; when the target steering characteristic is a steering characteristic having a stability coefficient correlation relationship with the reference steering characteristic among multiple steering characteristics, determine the reference stability coefficient of the target steering characteristic according to the reference stability coefficient of the reference steering characteristic and the first gain coefficient of the target steering characteristic, and determine the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic.

[0184] In a possible implementation manner, the device for controlling the steering of a vehicle further includes:

[0185] A self-learning unit is configured to iteratively perform a self-learning operation until a reference stability coefficient of a reference steering characteristic is determined when the vehicle is in a steady-state steering condition, the steering characteristic of the vehicle is the reference steering characteristic, and a self-learning condition is satisfied. The self-learning operation includes: determining a stability coefficient for which the self-learning operation is directed, determining a theoretical yaw rate of the vehicle for which the self-learning operation is directed according to the stability coefficient for which the self-learning operation is directed, and obtaining an actual yaw rate of the vehicle for which the self-learning operation is directed; when a difference between the actual yaw rate and the theoretical yaw rate of the vehicle is less than a lower difference threshold, determining the stability coefficient for which the self-learning operation is directed as the reference stability coefficient of the reference steering characteristic.

[0186] In a possible implementation, the target stability coefficient acquisition unit is further configured to obtain driving behavior characteristic information of the vehicle, where the driving behavior characteristic information includes: the actual yaw rate of the vehicle, the steering wheel angular acceleration of the vehicle's steering wheel, and the yaw rate ratio of the vehicle; determining a second gain coefficient of the target steering characteristic according to the driving behavior characteristic information of the vehicle; and determining a target stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic and the second gain coefficient.

[0187] In a possible implementation, the target stability coefficient acquisition unit is further configured to obtain a category related to road risk of the road on which the vehicle is traveling, where the category related to road risk is determined according to the number of vehicles traveling on the road and having a risk of instability during a statistical time period; and determining a second gain coefficient of the target steering characteristic according to the driving behavior characteristic information of the vehicle and the category related to road risk.

[0188] In a possible implementation, the target stability coefficient of the target steering characteristic is within the range of the stability coefficient corresponding to the target steering characteristic.

[0189] In this embodiment, the device is presented in the form of functional units. Here, the unit refers to an ASIC circuit, a processor and a memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0190] The further function descriptions of the above respective units are the same as those in the corresponding above embodiments, and will not be elaborated here.

[0191] Reference Figure 7, which shows a schematic structural diagram of a computer device provided by an embodiment of the present application. The computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including a high-speed interface and a low-speed interface. Each component communicates with each other using different buses and can be installed on a common motherboard or installed in other ways as needed. The processor can process instructions executed within the computer device, including instructions stored in the memory or on the memory to display graphical information of a GUI on an external input / output device (such as a display device coupled to the interface). In some alternative embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a set of blade servers, or a multi-processor system).

[0192] The processor 10 can be a central processing unit, a network processor, or a combination thereof. Among them, the processor 10 can further include a hardware chip. The above hardware chip can be an application-specific integrated circuit, a programmable logic device, or a combination thereof. The above programmable logic device can be a complex programmable logic device, a field programmable gate array, a general array logic, or any combination thereof.

[0193] Among them, the memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0194] The memory 20 can include a program storage area and a data storage area. Among them, the program storage area can store an operating system and application programs required for at least one function; the data storage area can store data created according to the use of the computer device. In addition, the memory 20 can include a high-speed random access memory and can also include a non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some alternative embodiments, the memory 20 can optionally include a memory remotely set relative to the processor 10, and these remote memories can be connected to the computer device through a network. Examples of the above network include but are not limited to the Internet, an enterprise intranet, a local area network, a mobile communication network, and combinations thereof.

[0195] The memory 20 can include a volatile memory, such as a random access memory; the memory can also include a non-volatile memory, such as a flash memory, a hard disk, or a solid-state drive; the memory 20 can also include a combination of the above types of memories.

[0196] The computer device further includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30, and the output device 40 can be connected through a bus or other means.

[0197] The input device 30 can receive input digital or character information and generate key signal inputs related to the user settings and function controls of the computer device, such as a touch screen, a keypad, a mouse, a trackpad, a touchpad, a pointing stick, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 can include a display device, an auxiliary lighting device (e.g., an LED), and a haptic feedback device (e.g., a vibration motor), etc. The above display device includes but is not limited to a liquid crystal display, a light emitting diode, a display, and a plasma display. In some alternative embodiments, the display device can be a touch screen.

[0198] The embodiments of the present application also provide a computer-readable storage medium. The methods according to the embodiments of the present application can be implemented in hardware, firmware, or be implemented as computer code that can be recorded on a storage medium, or be implemented as computer code that is originally stored in a remote storage medium or a non-transitory machine-readable storage medium and downloaded through a network and will be stored in a local storage medium, so that the methods described herein can be processed by such software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory, a random access memory, a flash memory, a hard disk, or a solid-state drive, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by the computer, the processor, or the hardware, the methods shown in the above embodiments are implemented.

[0199] A part of the embodiments of the present application can be applied as a computer program product, such as computer program instructions. When executed by a computer, through the operation of the computer, the methods and / or technical solutions according to the present invention can be executed or provided. Those skilled in the art should be able to understand that the forms in which computer program instructions exist in a computer-readable medium include but are not limited to source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include but are not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible by the computer.

[0200] Although the embodiments of the present application are described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for controlling the steering of a vehicle, characterized in that: The method comprises: acquiring a target stability coefficient of a target steering characteristic of the vehicle, wherein the target steering characteristic is a steering characteristic selected by a driver of the vehicle from a plurality of steering characteristics; determining a target yaw rate of the vehicle according to the target stability coefficient, and obtaining an actual yaw rate of the vehicle; determining a target additional yaw moment according to a target yaw angular velocity of the vehicle and an actual yaw angular velocity of the vehicle; A target wheel-end torque of the wheels of the vehicle is determined according to the target additional yaw moment, and the target wheel-end torque is applied to the wheels of the vehicle.

2. The method according to claim 1, characterized in that Obtaining a target stability coefficient of the target steering characteristic of the vehicle includes: When the target steering characteristic is a reference steering characteristic, determining a target stability coefficient of the target steering characteristic according to a reference stability coefficient of the reference steering characteristic; When the target steering characteristic is a steering characteristic among multiple steering characteristics that has a stability coefficient correlation relationship with a baseline steering characteristic, the baseline stability coefficient of the target steering characteristic is determined based on the baseline stability coefficient of the baseline steering characteristic and a first gain coefficient of the target steering characteristic, and the target stability coefficient of the target steering characteristic is determined based on the baseline stability coefficient of the target steering characteristic.

3. The method according to claim 2, characterized in that The method further comprises: When the vehicle is in a steady-state steering condition and the steering characteristic of the vehicle is a baseline steering characteristic and meets a self-learning condition, a self-learning operation is iteratively performed until a baseline stability coefficient of the baseline steering characteristic is determined, the self-learning operation comprising: determining a stability coefficient targeted by the self-learning operation, and determining a theoretical yaw angular velocity of the vehicle targeted by the self-learning operation based on the stability coefficient targeted by the self-learning operation, and obtaining an actual yaw angular velocity of the vehicle targeted by the self-learning operation; when a difference between an actual yaw angular velocity of the vehicle targeted by the self-learning operation and the theoretical yaw angular velocity is less than a lower limit difference threshold, determining the stability coefficient targeted by the self-learning operation as the baseline stability coefficient of the baseline steering characteristic.

4. The method according to claim 2, characterized in that: Determining the target stability coefficient of the target steering characteristic according to the reference stability coefficient of the target steering characteristic comprises: Acquiring driving behavior characteristic information of the vehicle, the driving behavior characteristic information comprising: an actual yaw angular velocity of the vehicle, a steering wheel angular acceleration of a steering wheel of the vehicle, and a yaw angular velocity ratio of the vehicle; Determining a second gain coefficient of a target steering characteristic according to the driving behavior characteristic information of the vehicle; A target stability coefficient of the target steering characteristic is determined according to the reference stability coefficient of the target steering characteristic and the second gain coefficient.

5. The method according to claim 4, characterized in that Determining the second gain coefficient of the target steering characteristic according to the driving behavior characteristic information of the vehicle includes: Obtaining a category related to road risk of the road on which the vehicle is traveling, wherein the category related to road risk is determined according to the number of vehicles traveling on the road and having a risk of instability during a statistical time period; A second gain coefficient of the target steering characteristic is determined according to the driving behavior characteristic information of the vehicle and the category related to the road risk.

6. The method according to any one of claims 2 to 5, characterized in that: The target stability coefficient of the target steering characteristic is within a stability coefficient range corresponding to the target steering characteristic.

7. A device for controlling the steering of a vehicle, characterized in that: Installed on a vehicle, the device comprises: a target stability coefficient acquisition unit, configured to acquire a target stability coefficient of a target steering characteristic of the vehicle, wherein the target steering characteristic is a steering characteristic selected by a driver of the vehicle from a plurality of steering characteristics; a yaw rate determination unit, configured to determine a target yaw rate of the vehicle according to the target stability coefficient, and to obtain an actual yaw rate of the vehicle; a target additional yaw moment determination unit, configured to determine a target additional yaw moment according to a target yaw angular velocity of the vehicle and an actual yaw angular velocity of the vehicle; The steering control unit is used to determine a target wheel-end torque of the wheels of the vehicle according to the target additional yaw moment, and to apply the target wheel-end torque to the wheels of the vehicle.

8. A computer device, characterized in that: Installed on the vehicle, including: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the method according to any one of claims 1 to 6 by executing the computer instructions.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the method according to any one of claims 1 to 6.

10. A computer program product, characterized in that The method comprises computer instructions for causing a computer to execute the method according to any one of claims 1 to 6.

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