Steering control method of vehicle and vehicle

Abstract

The present application discloses a vehicle steering control method and a vehicle, and belongs to the field of vehicle technology. The technical solution provided in the embodiment of the present application is adopted to obtain the initial steering control curve and vehicle parameters of the target vehicle. Based on the vehicle parameters, the target coordinates of multiple curve control points on the initial steering control curve are determined, and the curve control points are used to change the shape of the initial steering control curve, thereby changing the corresponding relationship between the rear front wheel steering ratio and the vehicle speed represented by the initial steering control curve. Based on the target coordinates of multiple curve control points, the initial steering control curve is adjusted to obtain a target steering control curve, and the target steering control curve is a steering control curve with good adaptability to the vehicle parameters. In response to the target vehicle turning, the target steering control curve is used to control the rear wheels of the target vehicle to steer, thereby fully utilizing the rear wheel steering function.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and more specifically, to a steering control method and a vehicle in the field of vehicle technology. Background Art

[0002] With the development of vehicle technology, more and more vehicles are equipped with rear-wheel steering systems, which can control the rear wheels of the vehicle to steer, thereby improving the steering performance of the vehicle.

[0003] In the related art, the rear-wheel steering ratio is usually pre-configured, the capacity of the rear-wheel steering system is not fully utilized, and the rear-wheel steering function is poorly adaptable to the vehicle.

[0004] Therefore, how to improve the adaptability of the rear-wheel steering function to the vehicle is a hot topic of research. Summary of the invention

[0005] The embodiment of the present application provides a vehicle steering control method and a vehicle, which can improve the adaptability of the rear wheel steering function and the vehicle. The technical solution is as follows:

[0006] In one aspect, a steering control method for a vehicle is provided, the method comprising:

[0007] Acquire an initial steering control curve and vehicle parameters of a target vehicle, wherein the initial steering control curve is used to represent the relationship between the rear-front wheel steering ratio and the vehicle speed, and the target vehicle has a rear-wheel steering function;

[0008] Based on the vehicle parameters, determining target coordinates of a plurality of curve control points on the initial steering control curve;

[0009] Based on the target coordinates of the multiple curve control points, the initial steering control curve is adjusted to obtain a target steering control curve;

[0010] In response to the target vehicle turning, the target steering control curve is used to control the rear wheels of the target vehicle to turn.

[0011] In a possible implementation manner, the multiple curve control points include a first curve control point, a second curve control point, a third curve control point, a fourth curve control point and a fifth curve control point, the vehicle speeds corresponding to the first curve control point, the second curve control point, the third curve control point, the fourth curve control point and the fifth curve control point increase in sequence, and determining the target coordinates of the multiple curve control points on the initial steering control curve based on the vehicle parameters includes:

[0012] Based on the vehicle parameters, determining target coordinates of the first curve control point, target coordinates of the second curve control point, target coordinates of the third curve control point, target coordinates of the fourth curve control point, and target coordinates of the fifth curve control point;

[0013] Among them, the first curve control point is the lowest point of the steering control curve, the second curve control point is the point corresponding to zero vehicle speed in the steering control curve, the third curve control point is the platform starting point of the steering control curve, the fourth curve control point is the platform end point of the steering control curve, the fifth curve control point is the highest point of the steering control curve, and the platform is the position in the steering control curve where the steering ratio of the rear and front wheels remains unchanged.

[0014] In a possible implementation manner, the vehicle parameters include vehicle attributes, vehicle driving parameters, vehicle yaw parameters, and yaw evaluation parameters, and determining, based on the vehicle parameters, target coordinates of the first curve control point, target coordinates of the second curve control point, target coordinates of the third curve control point, target coordinates of the fourth curve control point, and target coordinates of the fifth curve control point, includes:

[0015] Determining the target coordinates of the first curve control point based on the vehicle attributes and the yaw evaluation parameter, wherein the yaw evaluation parameter is used to represent the evaluation of the yaw condition of the target vehicle at different vehicle speeds by a target object, wherein the target object is a driver or a tester of the target vehicle;

[0016] Determining the target coordinates of the second curve control point based on the vehicle yaw parameter and the vehicle driving parameter, wherein the vehicle yaw parameter is used to represent the yaw conditions of the target vehicle at different vehicle speeds;

[0017] Determining target coordinates of the third curve control point and target coordinates of the fourth curve control point based on the vehicle attributes and the vehicle yaw parameter;

[0018] Based on the vehicle attributes, target coordinates of the fifth curve control point are determined.

[0019] In a possible implementation manner, the vehicle attributes include a rear wheel steering range and a required minimum turning radius, and determining the target coordinates of the first curve control point based on the vehicle attributes and the yaw evaluation parameter includes:

[0020] determining a minimum rear wheel steering angle indicated by the rear wheel steering range;

[0021] Substituting the minimum rear wheel steering angle, the required minimum turning radius and the yaw evaluation parameter into the first relationship data to obtain the target coordinates of the first curve control point;

[0022] Alternatively, the minimum rear wheel steering angle, the required minimum turning radius and the yaw evaluation parameter are used to query in the first relationship table to obtain the target coordinates of the first curve control point.

[0023] In a possible implementation manner, the vehicle driving parameter includes a vehicle driving mode, and determining the target coordinates of the second curve control point based on the vehicle yaw parameter and the vehicle driving parameter includes:

[0024] The vehicle yaw parameter and the vehicle driving mode are used to query in the second relationship table to obtain the target coordinates of the second curve control point.

[0025] In a possible implementation manner, the vehicle attribute includes a medium speed interval, and determining the target coordinates of the third curve control point and the target coordinates of the fourth curve control point based on the vehicle attribute and the vehicle yaw parameter includes:

[0026] Based on the minimum vehicle speed, the maximum vehicle speed and the vehicle yaw parameter of the medium speed interval, the target coordinates of the third curve control point and the target coordinates of the fourth curve control point are determined.

[0027] In a possible implementation manner, the vehicle attribute includes a rear wheel steering range, and determining the target coordinates of the fifth curve control point based on the vehicle attribute includes:

[0028] determining a maximum rear wheel steering angle indicated by the rear wheel steering range;

[0029] Based on the maximum rear wheel steering angle, target coordinates of the fifth curve control point are determined.

[0030] In a possible implementation manner, adjusting the initial steering control curve based on the target coordinates of the multiple curve control points to obtain a target steering control curve includes:

[0031] Using the target coordinates of the plurality of curve control points to update the coordinates of corresponding curve control points in the initial steering control curve to obtain a reference steering control curve;

[0032] The reference steering control curve is smoothed to obtain the target steering control curve.

[0033] In a possible implementation manner, the step of smoothing the reference steering control curve to obtain the target steering control curve includes:

[0034] Dividing the reference steering control curve into a plurality of curve segments using the plurality of curve control points;

[0035] Smoothing each of the curve segments using a curve smoothing method corresponding to each of the curve segments to obtain a reference curve segment corresponding to each of the curve segments;

[0036] Multiple reference curve segments are spliced ​​together to obtain the target steering control curve.

[0037] In a possible implementation manner, the smoothing of each of the curve segments using the curve change gradient corresponding to each of the curve segments to obtain a reference curve segment corresponding to each of the curve segments includes:

[0038] For a target curve segment among the plurality of curve segments, determining a curve change gradient of the target curve segment based on the acceleration of the target vehicle and a steering wheel angle change rate;

[0039] The target curve segment is smoothed by using the curve change gradient to obtain a reference curve segment corresponding to the target curve segment;

[0040] For multiple other curve segments among the multiple curve segments except the target curve segment, each of the other curve segments is smoothed using the curve smoothing methods corresponding to the multiple other curve segments respectively, so as to obtain a reference curve segment corresponding to each of the other curve segments.

[0041] In a possible implementation manner, in response to the target vehicle turning, using the target steering control curve to control the rear wheels of the target vehicle to turn includes:

[0042] In response to the target vehicle turning, determining a first steering angle of a front wheel of the target vehicle;

[0043] Determining a second steering angle of the rear wheels of the target vehicle based on the current vehicle speed of the target vehicle, the first steering angle, and the target steering control curve;

[0044] The rear wheels of the target vehicle are controlled to steer at the second steering angle.

[0045] In one aspect, a steering control device for a vehicle is provided, the device comprising:

[0046] An acquisition module, used for acquiring an initial steering control curve and vehicle parameters of a target vehicle, wherein the initial steering control curve is used for indicating a relationship between a rear-wheel steering ratio and a vehicle speed, and the target vehicle has a rear-wheel steering function;

[0047] a target coordinate determination module, used to determine target coordinates of a plurality of curve control points on the initial steering control curve based on the vehicle parameters;

[0048] A curve adjustment module, configured to adjust the initial steering control curve based on the target coordinates of the plurality of curve control points to obtain a target steering control curve;

[0049] The steering control module is used to control the rear wheels of the target vehicle to steer using the target steering control curve in response to the target vehicle steering.

[0050] In a possible implementation manner, the multiple curve control points include a first curve control point, a second curve control point, a third curve control point, a fourth curve control point and a fifth curve control point, and the vehicle speeds corresponding to the first curve control point, the second curve control point, the third curve control point, the fourth curve control point and the fifth curve control point increase in sequence. The target coordinate determination module is used to determine the target coordinates of the first curve control point, the second curve control point, the third curve control point, the fourth curve control point and the fifth curve control point based on the vehicle parameters; wherein the first curve control point is the lowest point of the steering control curve, the second curve control point is the point corresponding to zero vehicle speed in the steering control curve, the third curve control point is the platform starting point of the steering control curve, the fourth curve control point is the platform end point of the steering control curve, the fifth curve control point is the highest point of the steering control curve, and the platform is the position in the steering control curve where the steering ratio of the rear and front wheels remains unchanged.

[0051] In a possible implementation, the vehicle parameters include vehicle attributes, vehicle driving parameters, vehicle yaw parameters and yaw evaluation parameters. The target coordinate determination module is used to determine the target coordinates of the first curve control point based on the vehicle attributes and the yaw evaluation parameters, where the yaw evaluation parameters are used to represent the target object's evaluation of the yaw condition of the target vehicle at different vehicle speeds, and the target object is the driver or tester of the target vehicle; determine the target coordinates of the second curve control point based on the vehicle yaw parameters and the vehicle driving parameters, where the vehicle yaw parameters are used to represent the yaw condition of the target vehicle at different vehicle speeds; determine the target coordinates of the third curve control point and the target coordinates of the fourth curve control point based on the vehicle attributes and the vehicle yaw parameters; and determine the target coordinates of the fifth curve control point based on the vehicle attributes.

[0052] In one possible implementation, the vehicle attributes include a rear-wheel steering range and a required minimum turning radius, and the target coordinate determination module is used to determine the minimum rear-wheel steering angle indicated by the rear-wheel steering range; substitute the minimum rear-wheel steering angle, the required minimum turning radius and the yaw evaluation parameter into the first relationship data to obtain the target coordinates of the first curve control point; or, use the minimum rear-wheel steering angle, the required minimum turning radius and the yaw evaluation parameter to query in the first relationship table to obtain the target coordinates of the first curve control point.

[0053] In a possible implementation manner, the target coordinate determination module is used to query the second relationship table using the vehicle yaw parameter and the vehicle driving mode to obtain the target coordinates of the second curve control point.

[0054] In a possible implementation, the vehicle attributes include a medium speed interval, and the target coordinate determination module is used to determine the target coordinates of the third curve control point and the target coordinates of the fourth curve control point based on the minimum speed, the maximum speed and the vehicle yaw parameter of the medium speed interval.

[0055] In a possible implementation, the vehicle attributes include a rear-wheel steering range, and the target coordinate determination module is used to determine a maximum rear-wheel steering angle indicated by the rear-wheel steering range; and based on the maximum rear-wheel steering angle, determine the target coordinates of the fifth curve control point.

[0056] In a possible implementation, the curve adjustment module is used to use the target coordinates of the multiple curve control points to update the coordinates of the corresponding curve control points in the initial steering control curve to obtain a reference steering control curve; and smooth the reference steering control curve to obtain the target steering control curve.

[0057] In a possible implementation, the curve adjustment module is used to divide the reference steering control curve into multiple curve segments using the multiple curve control points; smooth each curve segment using a curve smoothing method corresponding to each curve segment to obtain a reference curve segment corresponding to each curve segment; and splice multiple reference curve segments to obtain the target steering control curve.

[0058] In a possible implementation, the curve adjustment module is used to determine, for a target curve segment among the multiple curve segments, a curve change gradient of the target curve segment based on the acceleration of the target vehicle and the steering wheel angle change rate; smooth the target curve segment using the curve change gradient to obtain a reference curve segment corresponding to the target curve segment; and for multiple other curve segments among the multiple curve segments except the target curve segment, smooth each of the other curve segments using the curve smoothing methods respectively corresponding to the multiple other curve segments to obtain a reference curve segment corresponding to each of the other curve segments.

[0059] In one possible implementation, the steering control module is used to determine a first steering angle of the front wheels of the target vehicle in response to the target vehicle turning; determine a second steering angle of the rear wheels of the target vehicle based on the current speed of the target vehicle, the first steering angle and the target steering control curve; and control the rear wheels of the target vehicle to turn at the second steering angle.

[0060] On the one hand, a vehicle is provided, comprising one or more processors and one or more memories, wherein at least one program code is stored in the one or more memories, and the program code is loaded and executed by the one or more processors to implement the operations performed by the steering control method of the vehicle.

[0061] On the one hand, a computer-readable storage medium is provided, in which at least one program code is stored, and the program code is loaded and executed by a processor to implement the operations performed by the vehicle steering control method.

[0062] The technical solution provided in the embodiment of the present application is adopted to obtain the initial steering control curve and vehicle parameters of the target vehicle. The initial steering control curve is used to represent the relationship between the rear front wheel steering ratio and the vehicle speed, that is, the rear front wheel steering ratio corresponding to different vehicle speeds can be found through the initial steering control curve. The initial steering control curve is the default steering control curve of the target vehicle. Based on the vehicle parameters, the target coordinates of multiple curve control points on the initial steering control curve are determined. The curve control points are used to change the shape of the initial steering control curve, thereby changing the corresponding relationship between the rear front wheel steering ratio and the vehicle speed represented by the initial steering control curve. Based on the target coordinates of multiple curve control points, the initial steering control curve is adjusted to obtain a target steering control curve, which is a steering control curve with good adaptability to the vehicle parameters. In response to the target vehicle turning, the target steering control curve is used to control the rear wheels of the target vehicle to turn, thereby achieving full utilization of the rear wheel steering function. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 is a schematic diagram of an implementation environment of a vehicle steering control method provided in an embodiment of the present application;

[0064] Figure 2 is a flow chart of a vehicle steering control method provided in an embodiment of the present application;

[0065] Figure 3 is a flow chart of another vehicle steering control method provided by an embodiment of the present application;

[0066] Figure 4 is a schematic diagram of an initial steering control curve provided in an embodiment of the present application;

[0067] Figure 5 is a schematic diagram of a vehicle model provided in an embodiment of the present application;

[0068] Figure 6 is a schematic diagram of a target steering control curve provided in an embodiment of the present application;

[0069] Figure 7 is a structural schematic diagram of a vehicle steering control device provided in an embodiment of the present application;

[0070] Figure 8 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] Rear-wheel steering system: A collection of hardware used to implement rear-wheel steering.

[0076] Rear-front wheel steering ratio: the ratio between the rear wheel steering angle and the front wheel steering angle. When the rear-front wheel steering ratio is 1, the front and rear wheels rotate in the same direction at the same angle; when the rear-front wheel steering ratio is -1, the front and rear wheels rotate in opposite directions at the same angle.

[0077] In the related art, the rear-front wheel steering ratio of a vehicle is usually fixed. For example, the rear-front wheel steering ratio is set to 0.2, so that when the front wheels of the vehicle turn 10 degrees, the rear wheels will turn 10×0.2=2 degrees. In actual driving, vehicles have different vehicle parameters. Using a fixed rear-front wheel steering ratio to control the vehicle to perform rear-wheel steering does not take into account the state differences of the vehicle under different vehicle parameters, resulting in the rear-wheel steering function of the vehicle not being fully utilized and the rear-wheel steering function being poorly compatible with the vehicle.

[0078] 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 vehicle steering control method provided in the embodiment of the present application includes a vehicle-mounted terminal 101 and a rear-wheel steering controller 102 .

[0079] The vehicle-mounted terminal 101 is a terminal arranged on the vehicle, and has the capability of data collection and data processing. 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, the 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 rear-wheel steering controller 102, and the rear-wheel steering controller 102 is used to control the rear-wheel steering of the vehicle, that is, to control the steering angle of the rear wheels of the vehicle. In the embodiment of the present application, the rear-wheel steering controller 102 belongs to the rear-wheel steering system of the vehicle, and the rear-wheel steering system is used to realize the rear-wheel steering function.

[0080] 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 types of vehicles equipped with a rear-wheel steering function, 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.

[0081] When the technical solution provided in the embodiment of the present application is applied to an electric vehicle, the initial steering control curve and vehicle parameters of the electric vehicle are obtained. The initial steering control curve is used to represent the relationship between the rear front wheel steering ratio and the vehicle speed, that is, the rear front wheel steering ratio corresponding to different vehicle speeds can be found through the initial steering control curve. The initial steering control curve is the default steering control curve of the electric vehicle. Based on the vehicle parameters, the target coordinates of multiple curve control points on the initial steering control curve are determined. The curve control points are used to change the shape of the initial steering control curve, thereby changing the corresponding relationship between the rear front wheel steering ratio and the vehicle speed represented by the initial steering control curve. Based on the target coordinates of multiple curve control points, the initial steering control curve is adjusted to obtain a target steering control curve, which is a steering control curve with good adaptability to the vehicle parameters. In response to the electric vehicle turning, the target steering control curve is used to control the rear wheels of the electric vehicle to turn, thereby fully utilizing the rear wheel steering function.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 201. The vehicle-mounted terminal obtains an initial steering control curve and vehicle parameters of a target vehicle, wherein the initial steering control curve is used to represent a relationship between a rear-front wheel steering ratio and a vehicle speed, and the target vehicle has a rear-wheel steering function.

[0086] The target vehicle is a vehicle equipped with a rear-wheel steering system, and the rear-wheel steering function of the target vehicle is provided by the rear-wheel steering system. The initial steering control curve is the default steering control curve of the target vehicle. In the case where the technical solution provided by the embodiment of the present application is not adopted, the vehicle-mounted terminal can use the initial steering control curve to control the rear wheels of the target vehicle to steer. The vehicle parameter is a set of parameters, and the vehicle parameter can reflect the vehicle state of the target vehicle.

[0087] 202. The vehicle-mounted terminal determines target coordinates of a plurality of curve control points on the initial steering control curve based on the vehicle parameters.

[0088] The curve control point is a point on the initial steering control curve, and the curve control point can change the shape of the steering control curve, thereby adjusting the relationship between the rear front wheel steering ratio and the vehicle speed, and realizing the adjustment of the rear wheel steering of the target vehicle. The target coordinates of the curve control point include a horizontal coordinate and a vertical coordinate, the horizontal coordinate is the vehicle speed, and the vertical coordinate is the rear front wheel steering ratio.

[0089] 203. The vehicle-mounted terminal adjusts the initial steering control curve based on the target coordinates of the multiple curve control points to obtain a target steering control curve.

[0090] Among them, adjusting the initial steering control curve is to adjust the shape of the initial steering control curve. Since the target coordinates of multiple curve control points are determined based on the vehicle parameters of the target vehicle, the obtained target steering control curve is a steering control curve that matches the vehicle parameters. Using the target steering control curve to control the rear wheel steering of the target vehicle can achieve better results.

[0091] 204. In response to the target vehicle turning, the vehicle-mounted terminal uses the target steering control curve to control the rear wheels of the target vehicle to turn.

[0092] Among them, the target vehicle turns the steering wheel of the target vehicle, and the rotation of the steering wheel will directly control the front wheels of the target vehicle to turn. Using the target steering control curve to control the rear wheels of the target vehicle to turn means controlling the rear wheels to turn along with the turning of the front wheels.

[0093] The technical solution provided in the embodiment of the present application is adopted to obtain the initial steering control curve and vehicle parameters of the target vehicle. The initial steering control curve is used to represent the relationship between the rear front wheel steering ratio and the vehicle speed, that is, the rear front wheel steering ratio corresponding to different vehicle speeds can be found through the initial steering control curve. The initial steering control curve is the default steering control curve of the target vehicle. Based on the vehicle parameters, the target coordinates of multiple curve control points on the initial steering control curve are determined. The curve control points are used to change the shape of the initial steering control curve, thereby changing the corresponding relationship between the rear front wheel steering ratio and the vehicle speed represented by the initial steering control curve. Based on the target coordinates of multiple curve control points, the initial steering control curve is adjusted to obtain a target steering control curve, which is a steering control curve with good adaptability to the vehicle parameters. In response to the target vehicle turning, the target steering control curve is used to control the rear wheels of the target vehicle to turn, thereby achieving full utilization of the rear wheel steering function.

[0094] It should be noted that the above steps 201-203 are a simple description of the vehicle steering control method provided in the embodiment of the present application. The following will combine some examples to explain the vehicle steering control method provided in the embodiment of the present application in more detail. Figure 3 Taking the execution subject as a vehicle-mounted terminal as an example, the method includes the following steps.

[0095] 301. The vehicle-mounted terminal generates an initial steering control curve of a target vehicle, where the initial steering control curve is used to represent the relationship between the rear-front wheel steering ratio and the vehicle speed. The target vehicle has a rear-wheel steering function.

[0096] The target vehicle is a vehicle equipped with a rear-wheel steering system, and the rear-wheel steering function of the target vehicle is provided by the rear-wheel steering system. The initial steering control curve is the default steering control curve of the target vehicle. If the technical solution provided in the embodiment of the present application is not adopted, the vehicle-mounted terminal can use the initial steering control curve to control the rear wheels of the target vehicle to steer.

[0097] In a possible implementation, the vehicle terminal obtains the vehicle attributes of the target vehicle, substitutes the vehicle attributes into the initial curve generation relationship data, and obtains the target curve generation relationship data, and converts the target curve generation relationship data into a curve to obtain the initial steering control curve.

[0098] The initial curve generation relationship data is used to represent the relationship between the rear front wheel steering ratio, vehicle speed, vehicle attributes and vehicle driving parameters. After the vehicle attributes and vehicle driving parameters are substituted into the initial curve generation relationship data, the vehicle attributes in the initial curve generation relationship data are replaced by specific values, and the target curve generation relationship data obtained can represent the relationship between the rear front wheel steering ratio and the vehicle speed. In the embodiment of the present application, the relationship data is a function.

[0099] In this implementation mode, the vehicle attributes of the target vehicle are substituted into the initial curve generation relationship data to obtain the corresponding target curve generation relationship data, and the target curve generation relationship data is converted into a curve to obtain the initial steering control curve, which is highly efficient.

[0100] For example, vehicle attributes include mass, front axle equivalent cornering stiffness, rear axle equivalent cornering stiffness, distance from center of mass to front axle, and distance from center of mass to rear axle. For example, the vehicle terminal substitutes the mass, front axle equivalent cornering stiffness, rear axle equivalent cornering stiffness, distance from center of mass to front axle, and distance from center of mass to rear axle into the following formula (1) to obtain target curve generation relationship data. Figure 4 The vehicle terminal uses the vehicle speed as the independent variable and the front wheel steering ratio as the dependent variable, and transforms the target curve generation relationship data into the Cartesian coordinate system to obtain the initial steering control curve 400.

[0101] (1)

[0102] in, is the rear wheel turning angle, is the front wheel turning angle, is the rear-front wheel steering ratio, is the distance from the center of mass to the front axle, is the distance from the center of mass to the rear axle, For quality, is the equivalent cornering stiffness of the rear axle, is the front axle equivalent cornering stiffness, is the vehicle speed, also known as the longitudinal vehicle speed.

[0103] In order to explain the above implementation more clearly, the source of the above formula (1) is explained below.

[0104] See also Figure 5 , the vehicle is simplified into a linear 2-DOF vehicle model for analysis. The suspension system of the vehicle model is simplified into a rigid connection. The influence of the road adhesion coefficient and the air resistance are not considered. The tire side slip characteristics are considered. In addition to the symbols in the above formula (1), there are other symbols. The other symbols are explained below. is the lateral force of the front wheel, is the lateral force on the rear wheel, is the sideslip angle of the center of mass, is the yaw angle, is the vehicle center of mass speed.

[0105] According to the rigid body motion force and torque balance equation, the vehicle model 200 can be expressed as the following formula (2).

[0106] (2)

[0107] in, For vehicles around The moment of inertia of the shaft.

[0108] When the driver performs steering operation, the rear wheel angle Front wheel angle The ratio between them needs to ensure the vehicle center of mass side slip angle in steady state is 0, and =0, =0, =0, the above formula (1) can be obtained.

[0109] 302. The vehicle-mounted terminal obtains an initial steering control curve and vehicle parameters of the target vehicle.

[0110] The vehicle parameter is a set of parameters, and the vehicle parameter can reflect the vehicle state of the target vehicle. In some embodiments, the vehicle parameter includes vehicle attributes, vehicle driving parameters, vehicle yaw parameters, and yaw evaluation parameters. The vehicle driving parameters include parameters related to driving behavior. The vehicle yaw parameters are used to indicate the yaw of the vehicle at different speeds. The yaw evaluation parameter is used to indicate the evaluation of the target object on the yaw of the vehicle at different speeds. The target object is the driver or tester of the vehicle. The yaw evaluation parameter is a subjective evaluation parameter.

[0111] 303. The vehicle-mounted terminal determines target coordinates of multiple curve control points on the initial steering control curve based on the vehicle parameters.

[0112] The curve control point is a point on the initial steering control curve, and the curve control point can change the shape of the steering control curve, thereby adjusting the relationship between the rear front wheel steering ratio and the vehicle speed, and realizing the adjustment of the rear wheel steering of the target vehicle. The target coordinates of the curve control point include a horizontal coordinate and a vertical coordinate, the horizontal coordinate is the vehicle speed, and the vertical coordinate is the rear front wheel steering ratio.

[0113] In a possible implementation, the multiple curve control points include a first curve control point, a second curve control point, a third curve control point, a fourth curve control point and a fifth curve control point. The vehicle speeds corresponding to the first curve control point, the second curve control point, the third curve control point, the fourth curve control point and the fifth curve control point respectively increase in sequence. Based on the vehicle parameters, the target coordinates of the first curve control point, the target coordinates of the second curve control point, the target coordinates of the third curve control point, the target coordinates of the fourth curve control point and the target coordinates of the fifth curve control point are determined.

[0114] Among them, the first curve control point is the lowest point of the steering control curve, the second curve control point is the point corresponding to zero vehicle speed in the steering control curve, the third curve control point is the platform starting point of the steering control curve, the fourth curve control point is the platform end point of the steering control curve, the fifth curve control point is the highest point of the steering control curve, and the platform is the position where the steering ratio of the rear and front wheels remains unchanged in the steering control curve. The first curve control point can be regarded as the lower limit of the steering control curve, so it is also called MinRatio; the fifth curve control point can be regarded as the upper limit of the steering control curve, so it is also called MaxRatio; when the independent variable of the steering control curve is the vehicle speed, the second curve control point is the intersection of the steering control curve and the horizontal axis, so it is also called VzeroRatio. In the embodiment of the present application, the platform refers to the area where the horizontal coordinate changes but the vertical coordinate remains unchanged. The third curve control point and the fourth curve control point are the starting point and end point of this area, so the third curve control point is also called Keepratio start , the fourth curve control point is also called Keepratio end .

[0115] Under this implementation mode, vehicle parameters are used to determine the target coordinates of the first curve control point, the second curve control point, the third curve control point, the fourth curve control point and the fifth curve control point, respectively. Subsequently, the initial steering control curve can be adjusted using the target coordinates of the first curve control point, the second curve control point, the third curve control point, the fourth curve control point and the fifth curve control point, respectively, to obtain a target steering control curve that is highly compatible with the target vehicle.

[0116] For example, the vehicle parameters include vehicle attributes, vehicle driving parameters, vehicle yaw parameters and yaw evaluation parameters. The vehicle-mounted terminal determines the target coordinates of the first curve control point based on the vehicle attributes and the yaw evaluation parameters. The yaw evaluation parameters are used to represent the target object's evaluation of the yaw condition of the target vehicle at different vehicle speeds. The target object is the driver or tester of the target vehicle. The vehicle-mounted terminal determines the target coordinates of the second curve control point based on the vehicle yaw parameters and the vehicle driving parameters. The vehicle yaw parameters are used to represent the yaw condition of the target vehicle at different vehicle speeds. The vehicle yaw parameters are also called dynamic yaw characteristics. The vehicle-mounted terminal determines the target coordinates of the third curve control point and the target coordinates of the fourth curve control point based on the vehicle attributes and the vehicle yaw parameters. The vehicle-mounted terminal determines the target coordinates of the fifth curve control point based on the vehicle attributes.

[0117] In order to explain the above examples more clearly, the technical solutions provided in the above examples will be described in several parts below.

[0118] In the first part, the vehicle-mounted terminal determines the target coordinates of the first curve control point based on the vehicle attributes and the yaw evaluation parameter.

[0119] In a possible implementation, the vehicle attribute includes a rear wheel steering range and a required minimum turning radius, and the vehicle terminal determines the minimum rear wheel steering angle indicated by the rear wheel steering range. The vehicle terminal substitutes the minimum rear wheel steering angle, the required minimum turning radius, and the yaw evaluation parameter into the first relationship data to obtain the target coordinates of the first curve control point.

[0120] Among them, the rear wheel steering range is limited by the physical structure of the rear wheel steering system of the target vehicle. The rear wheel steering range is usually (-a, b), a and b are absolute values ​​of angles, and the positive and negative signs can be used to compare sizes (b>-b) or to indicate the steering direction (- indicates reverse rotation, + indicates forward rotation). a and b are determined by the physical structure, and a and b can be the same or different, which is not limited in the embodiment of the present application. The minimum rear wheel steering angle is the lower limit of the rear wheel steering range, that is, -a mentioned above. The required minimum turning radius is set by the user or technician according to the actual situation, which is not limited in the embodiment of the present application. The yaw evaluation parameter is collected in the low-speed circle test. In the embodiment of the present application, the yaw evaluation parameter includes scores corresponding to different vehicle speeds. The first relationship data is used to represent the relationship between the minimum rear wheel steering angle, the required minimum turning radius, the yaw evaluation parameter and the target coordinates of the first curve control point. The first relationship data is obtained by fitting multiple sample minimum rear wheel steering angles, multiple sample required minimum turning radii, multiple sample yaw evaluation parameters and multiple first sample coordinates.

[0121] It should be noted that, since the first curve control point is the lowest point of the steering control curve, the horizontal coordinate of the first curve control point is 0, and the first relationship data is actually used to determine the vertical coordinate of the first curve control point.

[0122] In this implementation, by substituting the minimum rear wheel steering angle, the required minimum turning radius and the yaw evaluation parameter into the first relationship data, the target coordinates of the first curve control point can be obtained, and the determination efficiency of the target coordinates of the first curve control point is relatively high.

[0123] Another implementation of the first part is described below.

[0124] In a possible implementation, the vehicle attribute includes a rear wheel steering range and a required minimum turning radius, and the vehicle-mounted terminal determines the minimum rear wheel steering angle indicated by the rear wheel steering range. The vehicle-mounted terminal uses the minimum rear wheel steering angle, the required minimum turning radius, and the yaw evaluation parameter to query in the first relationship table to obtain the target coordinates of the first curve control point.

[0125] The first relationship table stores the relationship between the minimum rear wheel steering angle, the required minimum turning radius, the yaw evaluation parameter and the target coordinates of the first curve control point, and the target coordinates of the first curve control point can be queried using the first relationship table. In some embodiments, the first relationship table is configured by a technician according to actual conditions, and the embodiments of the present application do not limit this.

[0126] In this implementation, the target coordinates of the first curve control point can be directly queried using the first relationship table, which is highly efficient.

[0127] The second part, the vehicle-mounted terminal determines the target coordinates of the second curve control point based on the vehicle yaw parameter and the vehicle driving parameter.

[0128] In a possible implementation, the vehicle driving parameter includes a vehicle driving mode, and the vehicle-mounted terminal uses the vehicle yaw parameter and the vehicle driving mode to query in the second relationship table to obtain the target coordinates of the second curve control point.

[0129] Among them, the vehicle driving mode includes snow mode, off-road mode, sports mode, normal mode, etc., which are not limited in the embodiments of the present application. The second curve control point is the intersection of the steering control curve and the horizontal axis, that is, the ordinate of the second curve control point is 0, so when determining the target coordinates of the second curve control point, it is actually determining the horizontal coordinate of the second curve control point, that is, determining the vehicle speed corresponding to the second curve control point. In the sports mode, since the vehicle needs to have a certain degree of oversteering, the vehicle speed corresponding to the second curve control point can be increased, that is, the horizontal coordinate of the second curve control point is increased, and the second curve control point is on the right in the coordinate system. In the snow mode, since the vehicle needs to produce as little yaw as possible, the vehicle speed corresponding to the second curve control point can be reduced, that is, the horizontal coordinate of the second curve control point is reduced, and the second curve control point is on the left in the coordinate system. In some embodiments, the second relationship table is configured by a technician according to actual conditions, which is not limited in the embodiments of the present application.

[0130] In this implementation, the target coordinates of the second curve control point can be obtained by querying the second relationship table using the vehicle driving mode and the vehicle yaw parameter, and the determination efficiency is relatively high.

[0131] Part three: The vehicle-mounted terminal determines the target coordinates of the third curve control point and the target coordinates of the fourth curve control point based on the vehicle attributes and the vehicle yaw parameters.

[0132] In one possible implementation, the vehicle attributes include a medium speed range, and the vehicle terminal determines the target coordinates of the third curve control point and the target coordinates of the fourth curve control point based on the minimum speed, maximum speed and yaw parameters of the medium speed range.

[0133] The medium speed interval is divided by technicians according to actual conditions, and the embodiment of the present application does not limit this. In the embodiment of the present application, the platform of the steering control curve corresponds to the medium speed interval, so the third curve control point corresponds to the lowest speed of the medium speed interval, and the fourth curve control point corresponds to the highest speed of the medium speed interval.

[0134] It should be noted that, since the third curve control point and the fourth curve control point are located on the same platform, the third curve control point and the fourth curve control point have the same ordinate and different abscissa.

[0135] In this implementation manner, the target coordinates of the third curve control point and the target coordinates of the fourth curve control point can be determined by using the medium speed range and the vehicle yaw parameter, which is highly efficient.

[0136] For example, the vehicle terminal determines the lowest speed of the medium speed interval as the horizontal coordinate of the third curve control point, and determines the highest speed of the medium speed interval as the horizontal coordinate of the fourth curve control point. The vehicle terminal determines the vertical coordinates of the third curve control point and the fourth curve control point based on the vehicle yaw parameter, the lowest speed and the highest speed.

[0137] The following describes the manner in which the vehicle-mounted terminal determines the ordinates of the third curve control point and the fourth curve control point based on the vehicle yaw parameter, the minimum vehicle speed and the maximum vehicle speed in the above example.

[0138] In some embodiments, the vehicle terminal substitutes the vehicle yaw parameter, the minimum vehicle speed and the maximum vehicle speed into the second relationship data to obtain the vertical coordinates of the third curve control point and the fourth curve control point.

[0139] The second relationship data is obtained by fitting multiple sample vehicle yaw parameters, multiple sample minimum vehicle speeds, and multiple sample maximum vehicle speeds.

[0140] Part 4: The vehicle-mounted terminal determines the target coordinates of the fifth curve control point based on the vehicle attributes.

[0141] In a possible implementation, the vehicle attribute includes a rear wheel steering range, and the vehicle terminal determines a maximum rear wheel steering angle indicated by the rear wheel steering range. The vehicle terminal determines the target coordinates of the fifth curve control point based on the maximum rear wheel steering angle.

[0142] The fifth curve control point is used to control the upper limit of the steering control curve, so the abscissa of the fifth curve control point is theoretically positive infinity, and the ordinate is the maximum rear front wheel steering ratio corresponding to the maximum rear wheel steering angle. Since positive infinity cannot be represented on the curve, the abscissa of the fifth curve control point can be directly determined as the theoretical maximum driving speed of the target vehicle.

[0143] In this implementation manner, the target coordinates of the fifth curve control point can be determined using the maximum rear wheel steering angle, which is more efficient.

[0144] 304. The vehicle-mounted terminal adjusts the initial steering control curve based on the target coordinates of the multiple curve control points to obtain a target steering control curve.

[0145] Among them, adjusting the initial steering control curve is to adjust the shape of the initial steering control curve. Since the target coordinates of multiple curve control points are determined based on the vehicle parameters of the target vehicle, the obtained target steering control curve is a steering control curve that matches the vehicle parameters. Using the target steering control curve to control the rear wheel steering of the target vehicle can achieve better results.

[0146] In a possible implementation, the vehicle terminal uses the target coordinates of the multiple curve control points to update the coordinates of the corresponding curve control points in the initial steering control curve to obtain a reference steering control curve. The vehicle terminal smoothes the reference steering control curve to obtain the target steering control curve.

[0147] The purpose of smoothing is to eliminate abnormal points and outliers in the steering control curve, and to make the transition between points in the steering control curve smoother, so as to avoid a sudden change in the rear wheel steering angle when the target steering control curve is used to control the rear wheel steering.

[0148] In this implementation, the initial steering control curve can be adjusted using multiple curve control points to obtain a target steering control curve without the need to regenerate the target steering control curve, thereby achieving high efficiency.

[0149] In order to explain the above implementation more clearly, the above implementation will be explained in several parts below.

[0150] In the first part, the vehicle-mounted terminal uses the target coordinates of the multiple curve control points to update the coordinates of the corresponding curve control points in the initial steering control curve to obtain a reference steering control curve.

[0151] In a possible implementation, the vehicle-mounted terminal uses the target coordinates of the multiple curve control points to replace the coordinates of the corresponding curve control points in the initial steering control curve, thereby obtaining the reference steering control curve.

[0152] In the second part, the vehicle-mounted terminal smoothes the reference steering control curve to obtain the target steering control curve.

[0153] In a possible implementation, the vehicle-mounted terminal uses the multiple curve control points to divide the reference steering control curve into multiple curve segments. The vehicle-mounted terminal uses the curve smoothing method corresponding to each of the curve segments to smooth each of the curve segments to obtain a reference curve segment corresponding to each of the curve segments. The vehicle-mounted terminal splices multiple reference curve segments to obtain the target steering control curve.

[0154] For example, the vehicle-mounted terminal uses the multiple curve control points to divide the reference steering control curve into multiple curve segments. For the target curve segment among the multiple curve segments, the vehicle-mounted terminal determines the curve change gradient of the target curve segment based on the acceleration of the target vehicle and the steering wheel angle change rate. The vehicle-mounted terminal uses the curve change gradient to smooth the target curve segment to obtain a reference curve segment corresponding to the target curve segment. For multiple other curve segments among the multiple curve segments except the target curve segment, the vehicle-mounted terminal uses the curve smoothing methods corresponding to the multiple other curve segments to smooth each of the other curve segments to obtain a reference curve segment corresponding to each of the other curve segments. The vehicle-mounted terminal splices multiple reference curve segments to obtain the target steering control curve.

[0155] For example, the vehicle terminal determines the curve segment between the first curve control point and the second curve control point as the first curve segment, the curve segment between the second curve control point and the third curve control point as the second curve segment, the curve segment between the third curve control point and the fourth curve control point as the third curve segment, and the curve segment between the fourth curve control point and the fifth curve control point as the fourth curve segment, wherein the fourth curve segment is the target curve segment, and the first curve segment, the second curve segment and the third curve segment are other curve segments. The vehicle terminal substitutes the acceleration and steering wheel angle change rate of the target vehicle into the third relationship data to obtain the curve change gradient of the fourth curve segment. The vehicle terminal uses the curve change gradient to smooth the fourth curve segment so that the ordinate of the point in the fourth curve segment rises with the curve change gradient until it reaches the ordinate of the fifth curve control point, thereby obtaining the reference curve segment corresponding to the fourth curve segment. The vehicle terminal uses a moving average method, a local weighted regression method, and a filter method to smooth the first curve segment, the second curve segment, and the third curve segment to obtain a reference curve segment corresponding to the first curve segment, a reference curve segment corresponding to the second curve segment, and a reference curve segment corresponding to the third curve segment. The vehicle terminal splices the reference curve segments corresponding to the first curve segment, the second curve segment, the third curve segment, and the fourth curve segment, respectively, and smoothes the spliced ​​portion to obtain the target steering control curve. Figure 6 , shows a target steering control curve 600, from Figure 6 It can be seen that the overall trend of the rear-front wheel steering ratio increases with the increase of the vehicle speed, and there is a platform 601 on the target steering control curve, the starting point of the platform 601 is the third curve control point, and the end point is the fourth curve control point.

[0156] 305. In response to the target vehicle turning, the vehicle-mounted terminal uses the target steering control curve to control the rear wheels of the target vehicle to turn.

[0157] Among them, the target vehicle turns the steering wheel of the target vehicle, and the rotation of the steering wheel will directly control the front wheels of the target vehicle to turn. Using the target steering control curve to control the rear wheels of the target vehicle to turn means controlling the rear wheels to turn along with the turning of the front wheels.

[0158] In a possible implementation, in response to the target vehicle turning, the vehicle-mounted terminal determines a first steering angle of the front wheels of the target vehicle. The vehicle-mounted terminal determines a second steering angle of the rear wheels of the target vehicle based on the current speed of the target vehicle, the first steering angle, and the target steering control curve. The vehicle-mounted terminal controls the rear wheels of the target vehicle to turn at the second steering angle.

[0159] For example, in response to the target vehicle turning, the vehicle-mounted terminal determines a first steering angle of the front wheels of the target vehicle. The vehicle-mounted terminal uses the current speed of the target vehicle to query the target steering control curve to obtain a target rear front wheel steering ratio. The vehicle-mounted terminal multiplies the first steering angle by the target rear front wheel steering ratio to obtain a second steering angle of the rear wheels of the target vehicle. The vehicle-mounted terminal controls the rear wheels of the target vehicle to turn at the second steering angle.

[0160] 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.

[0161] The technical solution provided in the embodiment of the present application is adopted to obtain the initial steering control curve and vehicle parameters of the target vehicle. The initial steering control curve is used to represent the relationship between the rear front wheel steering ratio and the vehicle speed, that is, the rear front wheel steering ratio corresponding to different vehicle speeds can be found through the initial steering control curve. The initial steering control curve is the default steering control curve of the target vehicle. Based on the vehicle parameters, the target coordinates of multiple curve control points on the initial steering control curve are determined. The curve control points are used to change the shape of the initial steering control curve, thereby changing the corresponding relationship between the rear front wheel steering ratio and the vehicle speed represented by the initial steering control curve. Based on the target coordinates of multiple curve control points, the initial steering control curve is adjusted to obtain a target steering control curve, which is a steering control curve with good adaptability to the vehicle parameters. In response to the electric vehicle turning, the target steering control curve is used to control the rear wheels of the target vehicle to turn, thereby achieving full utilization of the rear wheel steering function.

[0162] Figure 7 is a structural schematic diagram of a vehicle steering control device provided in an embodiment of the present application, see Figure 7 The device includes: an acquisition module 701, a target coordinate determination module 702, a curve adjustment module 703 and a steering control module 704.

[0163] The acquisition module 701 is used to acquire an initial steering control curve and vehicle parameters of a target vehicle. The initial steering control curve is used to represent the relationship between the rear-front wheel steering ratio and the vehicle speed. The target vehicle has a rear-wheel steering function.

[0164] The target coordinate determination module 702 is used to determine the target coordinates of a plurality of curve control points on the initial steering control curve based on the vehicle parameters.

[0165] The curve adjustment module 703 is used to adjust the initial steering control curve based on the target coordinates of the multiple curve control points to obtain a target steering control curve.

[0166] The steering control module 704 is used to control the rear wheels of the target vehicle to steer using the target steering control curve in response to the target vehicle steering.

[0167] In a possible implementation, the plurality of curve control points include a first curve control point, a second curve control point, a third curve control point, a fourth curve control point and a fifth curve control point, and the vehicle speeds corresponding to the first curve control point, the second curve control point, the third curve control point, the fourth curve control point and the fifth curve control point increase in sequence, and the target coordinate determination module 702 is used to determine the target coordinates of the first curve control point, the second curve control point, the third curve control point, the fourth curve control point and the fifth curve control point based on the vehicle parameters. The first curve control point is the lowest point of the steering control curve, the second curve control point is the point corresponding to zero vehicle speed in the steering control curve, the third curve control point is the platform starting point of the steering control curve, the fourth curve control point is the platform end point of the steering control curve, the fifth curve control point is the highest point of the steering control curve, and the platform is the position where the rear and front wheel steering ratio remains unchanged in the steering control curve.

[0168] In a possible implementation, the vehicle parameters include vehicle attributes, vehicle driving parameters, vehicle yaw parameters, and yaw evaluation parameters. The target coordinate determination module 702 is used to determine the target coordinates of the first curve control point based on the vehicle attributes and the yaw evaluation parameters. The yaw evaluation parameters are used to represent the target object's evaluation of the yaw condition of the target vehicle at different vehicle speeds. The target object is the driver or tester of the target vehicle. Based on the vehicle yaw parameters and the vehicle driving parameters, the target coordinates of the second curve control point are determined. The vehicle yaw parameters are used to represent the yaw condition of the target vehicle at different vehicle speeds. Based on the vehicle attributes and the vehicle yaw parameters, the target coordinates of the third curve control point and the target coordinates of the fourth curve control point are determined. Based on the vehicle attributes, the target coordinates of the fifth curve control point are determined.

[0169] In a possible implementation, the vehicle attributes include a rear wheel steering range and a required minimum turning radius, and the target coordinate determination module 702 is used to determine the minimum rear wheel steering angle indicated by the rear wheel steering range. The minimum rear wheel steering angle, the required minimum turning radius, and the yaw evaluation parameter are substituted into the first relational data to obtain the target coordinates of the first curve control point. Alternatively, the minimum rear wheel steering angle, the required minimum turning radius, and the yaw evaluation parameter are used to query in the first relational table to obtain the target coordinates of the first curve control point.

[0170] In a possible implementation, the target coordinate determination module 702 is used to query the second relationship table using the vehicle yaw parameter and the vehicle driving mode to obtain the target coordinate of the second curve control point.

[0171] In one possible implementation, the vehicle attributes include a medium speed range, and the target coordinate determination module 702 is used to determine the target coordinates of the third curve control point and the target coordinates of the fourth curve control point based on the minimum speed, the maximum speed and the vehicle yaw parameter of the medium speed range.

[0172] In a possible implementation, the vehicle attribute includes a rear wheel steering range, and the target coordinate determination module 702 is used to determine a maximum rear wheel steering angle indicated by the rear wheel steering range, and determine the target coordinates of the fifth curve control point based on the maximum rear wheel steering angle.

[0173] In a possible implementation, the curve adjustment module 703 is used to update the coordinates of the corresponding curve control points in the initial steering control curve using the target coordinates of the multiple curve control points to obtain a reference steering control curve and to smooth the reference steering control curve to obtain the target steering control curve.

[0174] In a possible implementation, the curve adjustment module 703 is used to divide the reference steering control curve into multiple curve segments using the multiple curve control points, smooth each curve segment using a curve smoothing method corresponding to each curve segment, and obtain a reference curve segment corresponding to each curve segment, and splice multiple reference curve segments to obtain the target steering control curve.

[0175] In a possible implementation, the curve adjustment module 703 is used to determine the curve change gradient of the target curve segment among the multiple curve segments based on the acceleration of the target vehicle and the steering wheel angle change rate. The target curve segment is smoothed using the curve change gradient to obtain a reference curve segment corresponding to the target curve segment. For multiple other curve segments among the multiple curve segments except the target curve segment, each of the other curve segments is smoothed using the curve smoothing methods corresponding to the multiple other curve segments to obtain a reference curve segment corresponding to each of the other curve segments.

[0176] In a possible implementation, the steering control module 704 is used to determine a first steering angle of the front wheels of the target vehicle in response to the target vehicle turning. Based on the current speed of the target vehicle, the first steering angle and the target steering control curve, a second steering angle of the rear wheels of the target vehicle is determined. The rear wheels of the target vehicle are controlled to turn at the second steering angle.

[0177] It should be noted that: the vehicle steering control device provided in the above embodiment only uses the division of the above functional modules as an example when performing steering control. In actual applications, 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 vehicle steering control device provided in the above embodiment and the vehicle steering control method embodiment belong to the same concept, and the specific implementation process is detailed in the method embodiment, which will not be repeated here.

[0178] The technical solution provided in the embodiment of the present application is adopted to obtain the initial steering control curve and vehicle parameters of the target vehicle. The initial steering control curve is used to represent the relationship between the rear front wheel steering ratio and the vehicle speed, that is, the rear front wheel steering ratio corresponding to different vehicle speeds can be found through the initial steering control curve. The initial steering control curve is the default steering control curve of the target vehicle. Based on the vehicle parameters, the target coordinates of multiple curve control points on the initial steering control curve are determined. The curve control points are used to change the shape of the initial steering control curve, thereby changing the corresponding relationship between the rear front wheel steering ratio and the vehicle speed represented by the initial steering control curve. Based on the target coordinates of multiple curve control points, the initial steering control curve is adjusted to obtain a target steering control curve, which is a steering control curve with good adaptability to the vehicle parameters. In response to the electric vehicle turning, the target steering control curve is used to control the rear wheels of the target vehicle to turn, thereby achieving full utilization of the rear wheel steering function.

[0179] The embodiment of the present application also provides a vehicle, Figure 8It is a structural schematic diagram of a vehicle provided in an embodiment of the present application.

[0180] Typically, the vehicle 800 includes: one or more processors 801 and one or more memories 802 .

[0181] The processor 801 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 801 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 801 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 801 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 801 may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning.

[0182] The memory 802 may include one or more computer-readable storage media, which may be non-transitory. The memory 802 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in the memory 802 is used to store at least one computer program, which is used to be executed by the processor 801 to implement the vehicle steering control method provided in the method embodiment of the present application.

[0183] Those skilled in the art will understand that Figure 8 The structure shown in the figure does not constitute a limitation on the vehicle 800, and the vehicle 800 may include more or fewer components than shown in the figure, or combine certain components, or adopt a different arrangement of components.

[0184] 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 vehicle steering control method provided in the above embodiments.

[0185] This embodiment also provides a computer-readable storage medium, in which a computer program code is stored. When the computer program code is run on a computer, the computer executes the above-mentioned related method steps to implement a vehicle steering control method provided in the above embodiment.

[0186] This embodiment also provides a computer program product. When the computer program product is run on a computer, the computer is enabled to execute the above-mentioned related steps to implement a vehicle steering control method provided in the above embodiment.

[0187] 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.

[0188] 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.

[0189] 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.

[0190] 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 vehicle steering control method, characterized in that: The method comprises: Acquire an initial steering control curve and vehicle parameters of a target vehicle, wherein the initial steering control curve is used to represent the relationship between the rear-front wheel steering ratio and the vehicle speed, the target vehicle has a rear-wheel steering function, and the vehicle parameters include vehicle attributes, vehicle driving parameters, vehicle yaw parameters, and yaw evaluation parameters; Based on the vehicle parameters, determining target coordinates of a plurality of curve control points on the initial steering control curve, the plurality of curve control points comprising a first curve control point, a second curve control point, a third curve control point, a fourth curve control point and a fifth curve control point, the vehicle speeds corresponding to the first curve control point, the second curve control point, the third curve control point, the fourth curve control point and the fifth curve control point respectively increasing in sequence; The step of determining target coordinates of a plurality of curve control points on the initial steering control curve based on the vehicle parameters comprises: Based on the vehicle parameters, determining target coordinates of the first curve control point, target coordinates of the second curve control point, target coordinates of the third curve control point, target coordinates of the fourth curve control point, and target coordinates of the fifth curve control point; The first curve control point is the lowest point of the initial steering control curve, the second curve control point is the point corresponding to zero vehicle speed in the steering control curve, the third curve control point is the platform starting point of the steering control curve, the fourth curve control point is the platform end point of the steering control curve, the fifth curve control point is the highest point of the steering control curve, and the platform is the position in the steering control curve where the steering ratio of the rear and front wheels remains unchanged; Based on the target coordinates of the multiple curve control points, the initial steering control curve is adjusted to obtain a target steering control curve; In response to the target vehicle turning, the target steering control curve is used to control the rear wheels of the target vehicle to turn.

2. The method according to claim 1, characterized in that The determining, based on the vehicle parameters, target coordinates of the first curve control point, target coordinates of the second curve control point, target coordinates of the third curve control point, target coordinates of the fourth curve control point, and target coordinates of the fifth curve control point comprises: Determining the target coordinates of the first curve control point based on the vehicle attributes and the yaw evaluation parameter, wherein the yaw evaluation parameter is used to represent the evaluation of the yaw condition of the target vehicle at different vehicle speeds by a target object, wherein the target object is a driver or a tester of the target vehicle; Determining the target coordinates of the second curve control point based on the vehicle yaw parameter and the vehicle driving parameter, wherein the vehicle yaw parameter is used to represent the yaw conditions of the target vehicle at different vehicle speeds; Determining target coordinates of the third curve control point and target coordinates of the fourth curve control point based on the vehicle attributes and the vehicle yaw parameter; Based on the vehicle attributes, target coordinates of the fifth curve control point are determined.

3. The method according to claim 2, characterized in that The vehicle attributes include a rear wheel steering range and a required minimum turning radius, and determining the target coordinates of the first curve control point based on the vehicle attributes and the yaw evaluation parameter includes: determining a minimum rear wheel steering angle indicated by the rear wheel steering range; Substituting the minimum rear wheel steering angle, the required minimum turning radius and the yaw evaluation parameter into the first relationship data to obtain the target coordinates of the first curve control point; Alternatively, the minimum rear wheel steering angle, the required minimum turning radius and the yaw evaluation parameter are used to query in the first relationship table to obtain the target coordinates of the first curve control point.

4. The method according to claim 2, characterized in that: The vehicle driving parameter includes a vehicle driving mode, and determining the target coordinates of the second curve control point based on the vehicle yaw parameter and the vehicle driving parameter includes: The vehicle yaw parameter and the vehicle driving mode are used to query in the second relationship table to obtain the target coordinates of the second curve control point.

5. The method according to claim 2, characterized in that: The vehicle attribute includes a medium speed interval, and determining the target coordinates of the third curve control point and the target coordinates of the fourth curve control point based on the vehicle attribute and the vehicle yaw parameter includes: Based on the minimum vehicle speed, the maximum vehicle speed and the vehicle yaw parameter of the medium speed interval, the target coordinates of the third curve control point and the target coordinates of the fourth curve control point are determined.

6. The method according to claim 2, characterized in that The vehicle attributes include a rear wheel steering range, and determining the target coordinates of the fifth curve control point based on the vehicle attributes includes: determining a maximum rear wheel steering angle indicated by the rear wheel steering range; Based on the maximum rear wheel steering angle, target coordinates of the fifth curve control point are determined.

7. The method according to claim 1, characterized in that The adjusting the initial steering control curve based on the target coordinates of the multiple curve control points to obtain a target steering control curve includes: Using the target coordinates of the plurality of curve control points to update the coordinates of corresponding curve control points in the initial steering control curve to obtain a reference steering control curve; The reference steering control curve is smoothed to obtain the target steering control curve.

8. The method according to claim 7, characterized in that The step of smoothing the reference steering control curve to obtain the target steering control curve includes: Dividing the reference steering control curve into a plurality of curve segments using the plurality of curve control points; Smoothing each of the curve segments using a curve smoothing method corresponding to each of the curve segments to obtain a reference curve segment corresponding to each of the curve segments; Multiple reference curve segments are spliced ​​together to obtain the target steering control curve.

9. The method according to claim 8, characterized in that The step of smoothing each of the curve segments by using the curve change gradient corresponding to each of the curve segments to obtain a reference curve segment corresponding to each of the curve segments comprises: For a target curve segment among the plurality of curve segments, determining a curve change gradient of the target curve segment based on the acceleration of the target vehicle and a steering wheel angle change rate; The target curve segment is smoothed by using the curve change gradient to obtain a reference curve segment corresponding to the target curve segment; For multiple other curve segments among the multiple curve segments except the target curve segment, each of the other curve segments is smoothed using the curve smoothing methods corresponding to the multiple other curve segments respectively, so as to obtain a reference curve segment corresponding to each of the other curve segments.

10. The method according to claim 1, characterized in that In response to the target vehicle turning, controlling the rear wheels of the target vehicle to turn using the target steering control curve includes: In response to the target vehicle turning, determining a first steering angle of a front wheel of the target vehicle; Determining a second steering angle of the rear wheels of the target vehicle based on the current vehicle speed of the target vehicle, the first steering angle, and the target steering control curve; The rear wheels of the target vehicle are controlled to steer at the second steering angle.

11. A vehicle, characterized in that: The vehicle comprises: A memory for storing executable program codes; A processor, configured to call and run the executable program code from the memory, so that the vehicle executes the steering control method for the vehicle as described in any one of claims 1 to 10.

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