Method and device for controlling the steering angle of a vehicle based on steer-by-wire transmission ratio

Abstract

The application discloses a kind of based on drive-by-wire steering transmission ratio control vehicle steering angle method and device, it is related to vehicle technical field.Therein, the method includes: obtaining vehicle data and user data, wherein, vehicle data is used to indicate the angle information and motion information of vehicle in the process of driving, user data is used to indicate the driving habit of user;Vehicle target angular velocity gain is determined based on vehicle data;Determine target relationship based on user data, wherein, target relationship is used to indicate the relationship between angular velocity gain and vehicle speed;Target transmission ratio is determined based on target angular velocity gain and target relationship, wherein, target transmission ratio corresponds with vehicle speed;The steering angle of vehicle is controlled based on target transmission ratio.The application solves the technical problem that related art reduces axle deflection by increasing axle stabilizer, resulting in higher cost, not easy to implement, lower comprehensiveness.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, in particular to a method and device for controlling a steering angle of a vehicle based on a steer-by-wire transmission ratio. BACKGROUND

[0002] With the rapid development of vehicle technology, steer-by-wire as a new technology in the field of vehicles has become an essential part of future vehicle control systems. Vehicles usually have a self-steering effect, which means that when the driver sharply decelerates, the sensitivity of the vehicle will increase rapidly. If the steering wheel angle remains unchanged, the wheel angle will increase sharply, which will make the vehicle body rotate too fast and cause safety hazards. Therefore, it is necessary to control the steering angle of the vehicle based on the steer-by-wire transmission ratio.

[0003] Currently, the self-steering effect of the vehicle is improved by increasing the axle stabilizer bar to reduce the axle offset, but this method requires additional installation of mechanical components and cannot adapt to different driving habits and different vehicle speed changes, resulting in high cost, difficulty in implementation and low comprehensiveness.

[0004] To address the above problems, no effective solutions have been proposed so far. SUMMARY

[0005] The embodiments of the present application provide a method and device for controlling a steering angle of a vehicle based on a steer-by-wire transmission ratio, to at least solve the technical problem of high cost, difficulty in implementation and low comprehensiveness caused by increasing the axle stabilizer bar to reduce the axle offset in the related art.

[0006] According to one embodiment of the present application, a method for controlling a steering angle of a vehicle based on a steer-by-wire transmission ratio is provided, comprising: obtaining vehicle data and user data, wherein the vehicle data is used to represent the steering angle information and motion information of the vehicle during driving, and the user data is used to represent the driving habits of the user; determining a target angular velocity gain of the vehicle based on the vehicle data; determining a target relationship based on the user data, wherein the target relationship is used to represent the relationship between the angular velocity gain and the vehicle speed; determining a target transmission ratio based on the target angular velocity gain and the target relationship, wherein the target transmission ratio corresponds to the vehicle speed; and controlling the steering angle of the vehicle based on the target transmission ratio.

[0007] Optionally, the vehicle mechanical relationship is obtained, wherein the vehicle mechanical relationship is used to represent the balance relationship between the force and the torque of the vehicle; and the vehicle data is multiplied according to the vehicle mechanical relationship to obtain a target motion model.

[0008] Optionally, the vehicle data at least comprises one of a steering wheel angle of the vehicle, an initial gear ratio of the vehicle, determining the target angular velocity gain of the vehicle based on the vehicle data comprises: determining a first expression based on the steering wheel angle and the initial gear ratio of the vehicle, wherein the first expression is used to represent a front wheel angle of the vehicle; determining a second expression by a target motion model based on the first expression, wherein the second expression is used to represent the target angular velocity gain.

[0009] Optionally, determining the target relationship based on the user data comprises: in response to the vehicle speed being greater than a first vehicle speed threshold and less than or equal to a second vehicle speed threshold, controlling the target angular velocity gain based on the user data to be unchanged to obtain a first target relationship; or, in response to the vehicle speed being greater than the second vehicle speed threshold, controlling the target angular velocity gain based on the user data to decrease to obtain a second target relationship.

[0010] Optionally, in response to the acceleration of the vehicle being greater than a first acceleration threshold, the first vehicle speed is determined; a corresponding first gear ratio is determined according to the first vehicle speed, wherein the first gear ratio corresponds to a first steering angle; and the steering angle of the vehicle is controlled to be the first steering angle.

[0011] Optionally, when the steering angle of the vehicle is the first steering angle, in response to the vehicle speed meeting a first preset condition and the steering wheel angle meeting a second preset condition, or the vehicle speed being greater than a first vehicle speed, the steering angle of the vehicle is controlled based on the target angular velocity gain and the target relationship.

[0012] According to an embodiment of the present application, a device for controlling a steering angle of a vehicle based on a steer-by-wire gear ratio is also provided, comprising: an acquisition module, the acquisition module being configured to acquire vehicle data and user data, wherein the vehicle data is used to represent steering angle information and motion information of the vehicle in a driving process, and the user data is used to represent driving habits of a user; a first determination module, the first determination module being configured to determine a target angular velocity gain of the vehicle based on the vehicle data; a second determination module, the second determination module being configured to determine a target relationship based on the user data, wherein the target relationship is used to represent a relationship between the angular velocity gain and a vehicle speed; a third determination module, the third determination module being configured to determine a target gear ratio based on the target angular velocity gain and the target relationship, wherein the target gear ratio corresponds to the vehicle speed; and a control module, the control module being configured to control the steering angle of the vehicle based on the target gear ratio.

[0013] Optionally, the first determination module is further configured to acquire a vehicle mechanical relationship, wherein the vehicle mechanical relationship is used to represent a balance relationship between a force and a torque of the vehicle; and to perform a product operation on the vehicle data according to the vehicle mechanical relationship to obtain a target motion model.

[0014] Optionally, the first determining module is further configured to determine a first expression based on a steering wheel angle of the vehicle and the initial transmission ratio, wherein the first expression is used to represent a front wheel angle of the vehicle; determine a second expression based on the target motion model and the first expression, wherein the second expression is used to represent a target angular velocity gain.

[0015] Optionally, the second determining module is further configured to, in response to the vehicle speed being greater than the first vehicle speed threshold and less than or equal to the second vehicle speed threshold, determine that the target angular velocity gain is controlled based on the user data to be constant, to obtain a first target relationship; or, in response to the vehicle speed being greater than the second vehicle speed threshold, determine that the target angular velocity gain is controlled based on the user data to decrease, to obtain a second target relationship.

[0016] Optionally, the third determining module is further configured to, in response to the acceleration of the vehicle being greater than the first acceleration threshold, determine the first vehicle speed; determine a first transmission ratio corresponding to the first steering angle according to the first vehicle speed, wherein the first transmission ratio corresponds to the first steering angle; and control the steering angle of the vehicle to be the first steering angle.

[0017] Optionally, the third determining module is further configured to, when the steering angle of the vehicle is the first steering angle, in response to the vehicle speed meeting a first preset condition and the steering wheel angle meeting a second preset condition, or the vehicle speed being greater than the first vehicle speed, control the steering angle of the vehicle based on the target angular velocity gain and the target relationship.

[0018] According to an embodiment of the present application, a vehicle is further provided, and the vehicle is configured to execute the method for controlling a steering angle of the vehicle based on a steer-by-wire transmission ratio in any of the above embodiments.

[0019] According to an embodiment of the present application, a computer readable storage medium is further provided, and the storage medium stores a computer program, wherein the computer program is configured to execute the method for controlling a steering angle of the vehicle based on a steer-by-wire transmission ratio in any of the above embodiments when the computer program is executed on a computer or a processor.

[0020] According to an embodiment of the present application, an electronic device is further provided, and the electronic device comprises a memory and a processor, the memory stores a computer program, and the processor is configured to execute the computer program to execute the method for controlling a steering angle of the vehicle based on a steer-by-wire transmission ratio in any of the above embodiments.

[0021] In the embodiment of the present application, vehicle data and user data are acquired, wherein the vehicle data is used to represent the turning angle information and motion information of the vehicle during driving, and the user data is used to represent the driving habit of the user, the target angular velocity gain of the vehicle is determined based on the vehicle data, the target relationship is determined based on the user data, wherein the target relationship is used to represent the relationship between the angular velocity gain and the vehicle speed, the target transmission ratio is determined based on the target angular velocity gain and the target relationship, wherein the target transmission ratio corresponds to the vehicle speed, and finally the steering angle of the vehicle is controlled based on the target transmission ratio, so that the target transmission ratio which makes the vehicle flexible at low speed and stable at high speed can be determined, the needs of the vehicle at different vehicle speeds are considered, the cost is low, the implementation is easy, the comprehensiveness is high, and the technical problems in the related art that the cost is high and the implementation is not easy due to the increase of the axle stabilizer to reduce the axle deviation are solved. BRIEF DESCRIPTION OF DRAWINGS

[0022] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

[0023] Figure 1 is a flow chart of a method for controlling the steering angle of a vehicle based on a steer-by-wire transmission ratio according to an embodiment of the present application;

[0024] Figure 2 is a schematic diagram for defining vehicle data according to an embodiment of the present application;

[0025] Figure 3 is a schematic diagram for determining a target relationship according to an embodiment of the present application;

[0026] Figure 4 is a schematic diagram for determining a target transmission ratio according to an embodiment of the present application;

[0027] Figure 5 is a schematic diagram of the change of the steering wheel angle with time according to an embodiment of the present application;

[0028] FIG. 6(a) is a schematic diagram of the change of the vehicle speed according to an embodiment of the present application;

[0029] FIG. 6(b) is a schematic diagram of the change of the wheel angle with the vehicle speed according to an embodiment of the present application;

[0030] FIG. 7(a) is a schematic diagram of the change of the vehicle speed according to another embodiment of the present application;

[0031] FIG. 7(b) is a schematic diagram of the change of the wheel angle with the vehicle speed according to another embodiment of the present application;

[0032] Figure 8(a) is a schematic diagram of the front wheel steering angle variation according to an embodiment of the present application;

[0033] Figure 8(b) is a schematic diagram of the yaw rate variation according to an embodiment of the present application;

[0034] Figure 8(c) is a schematic diagram of the center of mass side slip angle variation according to an embodiment of the present application;

[0035] Figure 9(a) is a schematic diagram of the front wheel steering angle variation according to another embodiment of the present application;

[0036] Figure 9(b) is a schematic diagram of the yaw rate variation according to another embodiment of the present application;

[0037] Figure 9(c) is a schematic diagram of the center of mass side slip angle variation according to another embodiment of the present application;

[0038] Figure 10 Figure 10 is a block diagram of a device for controlling the steering angle of a vehicle based on the transmission ratio according to an embodiment of the present application. DETAILED DESCRIPTION

[0039] For the sake of understanding, some explanations of concepts related to embodiments of the present application are provided by way of example for reference.

[0040] As follows:

[0041] Steer-by-wire: refers to a method of controlling the steering of a vehicle through electronic signals, using radio equipment to send instructions from the operator to a receiver installed on the vehicle, and then converting the instructions into electronic signals by the receiver, through corresponding driving elements (such as steering gear) to achieve control of the steering wheel or front wheels, thereby achieving the purpose of changing the direction and angle of travel.

[0042] Yaw rate gain: refers to a parameter in the control system for adjusting the lateral dynamic performance of the vehicle, which is usually represented as Kv. This parameter affects the yaw rate response and stability of the vehicle when turning. If the Kv value is too small, the vehicle may appear to be over-stable or under-stable; while if the Kv value is too large, it may lead to over-sensitivity or oscillation problems. Therefore, selecting the appropriate yaw rate gain is of great significance to improve the driving quality and safety of the vehicle.

[0043] Vehicle transmission ratio: refers to the speed ratio between the engine output shaft and the driving wheels. It is usually used to describe the way in which the engine output power is distributed to the wheels under different gear ratios or differential conditions. The transmission ratio can affect factors such as acceleration performance, fuel economy and maximum speed.

[0044] Self-steering effect of vehicle: refers to a lateral moment generated when the vehicle turns due to the distance between the front wheels and the rear wheels, which makes the vehicle body have a deflection tendency. This effect will affect the stability and handling performance of the vehicle, especially at low speed or sharp turns.

[0045] In order to make the personnel in the technical field better understand the present application scheme, the technical scheme in the embodiment of the present application will be described clearly and completely below in combination with the drawings in the embodiment of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should belong to the scope of protection of the present application.

[0046] It should be noted that the terms "first", "second" and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or a chronological sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0047] According to one embodiment of the present application, an embodiment of a method for controlling the steering angle of a vehicle based on the transmission ratio of a steer-by-wire system is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in a different order than that shown herein.

[0048] The method embodiment can be executed in an electronic device, a similar control device or system containing a memory and a processor. Taking the electronic device as an example, the electronic device can include one or more processors and a memory for storing data. Optionally, the above-mentioned electronic device can also include a communication device for communication function and a display device. Those skilled in the art can understand that the above structure description is only illustrative, which does not limit the structure of the above-mentioned electronic device. For example, the electronic device can also include more or less components than the above structure description, or have a different configuration from the above structure description.

[0049] The processor can include one or more processing units. For example, the processor can include a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processing (DSP) chip, a microcontroller unit (MCU), a field-programmable gate array (FPGA), a neural-network processing unit (NPU), a tensor processing unit (TPU), an artificial intelligent (AI) type processor, or the like. Different processing units can be independent components or integrated in one or more processors. In some examples, the electronic device can also include one or more processors.

[0050] The memory can be used to store a computer program, for example, a computer program corresponding to the method of controlling a vehicle steering angle based on a steer-by-wire transmission ratio in an embodiment of the present application. The processor can implement the above-mentioned method of controlling a vehicle steering angle based on a steer-by-wire transmission ratio by running the computer program stored in the memory. The memory can include a high-speed random access memory, and can also include a non-volatile memory, such as one or more magnetic storage devices, flash memories, or other non-volatile solid-state memories. In some examples, the memory can further include a memory remotely disposed relative to the processor, which can be connected to the electronic device through a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0051] The communication device is used to receive or send data via a network. Specific examples of the above-mentioned network can include a wireless network provided by a communication provider of a mobile terminal. In one example, the communication device includes a network interface controller (NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the communication device can be a radio frequency (RF) module, which is used to communicate with the Internet in a wireless manner.

[0052] The display device can be, for example, a liquid crystal display (LCD) and a touch display (also known as a "touch screen" or "touch display screen") in the form of a touch screen. The liquid crystal display can enable a user to interact with a user interface of the mobile terminal. In some embodiments, the mobile terminal described above has a graphical user interface (GUI), which can be interactive, including for example the following interactive functions: web browsing, drawing, word processing, creating electronic documents, playing games, video conferencing, instant messaging, sending and receiving e-mails, call interface, playing digital videos, playing digital music, and / or web browsing, etc. Executable instructions for performing the above interactive functions are configured / stored in one or more computer program products or readable storage media executable by the processor.

[0053] In the present embodiment, a method for controlling a vehicle steering angle based on a steer-by-wire transmission ratio is provided, Figure 1 is a flowchart of the method for controlling a vehicle steering angle based on a steer-by-wire transmission ratio according to an embodiment of the present application, as shown in Figure 1 The flowchart includes the following steps:

[0054] In step S10, vehicle data and user data are obtained.

[0055] The vehicle data is used to represent the steering angle information and motion information of the vehicle during driving, and the user data is used to represent the driving habits of the user.

[0056] It can be understood that during driving, the working state of the vehicle changes with the change of the vehicle speed, and the vehicle data changes accordingly. The vehicle data is used to represent the steering angle information and motion information of the vehicle during driving. The steering angle information can be understood as the steering angle of each component in the steering system during driving, such as the front and rear wheel steering angles, etc., which are not limited by the embodiments of the present application. The motion information can be understood as a physical quantity representing the working state of each component in the steering system during driving, such as the yaw rate, mass center forward speed, etc., which are not limited by the embodiments of the present application.

[0057] The user data is used to represent the driving habits of the user, such as the daily driving habits of professional drivers and ordinary users, etc., which are not limited by the embodiments of the present application.

[0058] The step can be understood as obtaining the turning angle information and motion information of the vehicle during driving and the user data representing the driving habit of the user, that is, obtaining the turning angle of each component in the steering system of the vehicle during driving and the physical quantity of each component in the steering system during working, and the user data representing the driving habit of the user.

[0059] Alternatively, the turning angle of each component in the steering system of the vehicle during driving and the physical quantity of each component in the steering system during working, and the user data representing the driving habit of the user can be obtained through the vehicle controller, that is, the vehicle data and the user data are obtained, and the embodiment of the present application is not limited.

[0060] In step S11, the target angular velocity gain of the vehicle is determined based on the vehicle data.

[0061] The target angular velocity gain can be understood as the yaw angular velocity gain in the steering system of the vehicle, which is used to reflect the yaw angular velocity response and stability of the vehicle during turning.

[0062] The step can be understood as determining the yaw angular velocity gain of the vehicle based on the turning angle of each component in the steering system of the vehicle during driving and the physical quantity of each component in the steering system during working, and the user data representing the driving habit of the user.

[0063] Alternatively, the target angular velocity gain can be determined by mathematical modeling, obtaining the state space expression, and then selecting a suitable control strategy according to the control requirements and system characteristics, and the embodiment of the present application is not limited.

[0064] It can be understood that when determining the yaw angular velocity gain, the response is as fast and accurate as possible under the premise of ensuring stability. Generally, the gain value can be adjusted by trial and error method, and whether the response meets the requirements is observed. The modern control theory can also be used to optimize the design scheme and determine the gain value, and the embodiment of the present application is not limited.

[0065] In step S12, the target relationship is determined based on the user data.

[0066] The target relationship is used to represent the relationship between the angular velocity gain and the vehicle speed.

[0067] The step can be understood as determining the relationship between the angular velocity gain and the vehicle speed based on the user data representing the driving habit of the user.

[0068] Optionally, the change of the angular velocity gain with the vehicle speed can be recorded according to the driving habits of the user, so as to determine the target relationship, and the embodiments of the present application are not limited thereto. For example, the change of the angular velocity gain with the vehicle speed can be recorded according to the daily driving habits of professional drivers and ordinary users, so as to obtain the relationship between the angular velocity gain and the vehicle speed, i.e., the target relationship, and the embodiments of the present application are not limited thereto.

[0069] In step S13, the target transmission ratio is determined based on the target angular velocity gain and the target relationship.

[0070] The target transmission ratio corresponds to the vehicle speed.

[0071] The target transmission ratio can be understood as the speed ratio between the output shaft of the vehicle engine and the driving wheel. This step can be understood as determining the target transmission ratio corresponding to the vehicle speed based on the yaw angular velocity gain in the vehicle steering system and the relationship between the angular velocity gain and the vehicle speed.

[0072] In step S14, the steering angle of the vehicle is controlled based on the target transmission ratio.

[0073] This step can be understood as controlling the steering angle of the vehicle based on the target transmission ratio corresponding to the vehicle speed. It can be understood that the target transmission ratio changes with the change of the vehicle speed, so that the vehicle is sensitive at low speed and stable at high speed, and the needs of the vehicle at different speeds are considered.

[0074] Through the above steps, the vehicle data and the user data are obtained, wherein the vehicle data is used to represent the turning angle information and the motion information of the vehicle during driving, and the user data is used to represent the driving habits of the user. The target angular velocity gain of the vehicle is determined based on the vehicle data, and the target relationship is determined based on the user data, wherein the target relationship is used to represent the relationship between the angular velocity gain and the vehicle speed. The target transmission ratio is determined based on the target angular velocity gain and the target relationship, wherein the target transmission ratio corresponds to the vehicle speed. Finally, the steering angle of the vehicle is controlled based on the target transmission ratio, so that the target transmission ratio that makes the vehicle flexible at low speed and stable at high speed is determined, the needs of the vehicle at different speeds are considered, the cost is low, the implementation is easy, the comprehensiveness is high, and the technical problems of the related art that the cost is high and the implementation is not easy due to the increase of the axle stabilizer bar to reduce the axle offset are solved.

[0075] Optionally, in step S11, the following execution step can also be included:

[0076] In step S110, the vehicle mechanical relationship is obtained.

[0077] The vehicle mechanical relationship is used to represent the balance relationship between the force and the torque of the vehicle.

[0078] It can be understood that the balance between the force and the moment is very important during the driving of the vehicle. When a vehicle is driving, various resistances such as air resistance, friction resistance and weight need to be overcome, which are external forces acting on the vehicle. At the same time, the engine also generates a driving force, and the energy is transmitted to the tire through the transmission system. Therefore, in order to maintain a stable driving state, it is necessary to balance the external resistances acting on the vehicle and the driving force generated by the engine.

[0079] Optionally, the vehicle mechanical relationship can be obtained through mathematical calculation and measurement analysis, and the embodiments of the present application are not limited.

[0080] In step s111, the vehicle data is multiplied according to the vehicle mechanical relationship to obtain a target motion model.

[0081] The target motion model can be understood as a relationship between the vehicle data during the motion of the vehicle. This step can be understood as multiplying the vehicle data according to the balance relationship between the force and the moment of the vehicle to obtain the target motion model.

[0082] Optionally, the vehicle data representing the turning angle information and the motion information of the vehicle during driving can be defined, and the defined parameters are multiplied according to the vehicle mechanical relationship to obtain the target motion model, and the embodiments of the present application are not limited.

[0083] Figure 2 is a schematic diagram of defining vehicle data according to an embodiment of the present application, as shown in Figure 2 , the specific process of defining the vehicle data is comprehensively described, Figure 2 , β is the center of mass side slip angle, ωr is the yaw rate, u is the center of mass forward speed, υ is the center of mass lateral speed, a and b are the distances from the front and rear axles to the center of mass, L is the wheelbase, δ f , δ r are the turning angles of the front and rear wheels, α f , α r are the tire side slip angles of the front and rear wheels.

[0084] Specifically, the center of mass side slip angle can be denoted as β, the yaw rate can be denoted as ωr, the center of mass forward speed can be denoted as u, the center of mass lateral speed can be denoted as υ, the distances from the front and rear axles to the center of mass can be denoted as a and b respectively, the wheelbase can be denoted as L, the turning angles of the front and rear wheels can be denoted as δ f , δ r , and the tire side slip angles of the front and rear wheels can be denoted as α f , α r , then the target motion model can be calculated by mathematical formula, and the specific calculation process is shown in the following formula (1)-(2):

[0085]

[0086]

[0087] wherein m in the above formula (1)-(2) is the mass of the whole vehicle, k1, k2 are the cornering stiffness of the front and rear axles respectively, I Z is the yaw moment of inertia, the side slip angle β of the mass center can be expressed by the forward speed u of the mass center and the lateral speed υ of the mass center, and the specific expression is shown in the following formula (3):

[0088]

[0089] The target motion model is determined in this way, and embodiments of the present application are not limited.

[0090] Optionally, in step S11, the vehicle data at least includes one of the following: a steering wheel angle of the vehicle, an initial transmission ratio of the vehicle, and determining the target angular velocity gain of the vehicle based on the vehicle data can include the following steps:

[0091] Step S112, determining a first expression based on the steering wheel angle and the initial transmission ratio of the vehicle;

[0092] Wherein the first expression is used to represent the front wheel angle of the vehicle.

[0093] This step can be understood as determining the first expression for representing the front wheel angle of the vehicle based on the steering wheel angle and the initial transmission ratio of the vehicle.

[0094] Optionally, the first expression for representing the front wheel angle of the vehicle can be obtained by multiplying the steering wheel angle and the initial transmission ratio of the vehicle, and embodiments of the present application are not limited. Exemplarily, the steering wheel angle of the vehicle can be denoted as δ h , and the initial transmission ratio of the vehicle is denoted as i, then the front wheel angle δ f of the vehicle can be calculated by a mathematical formula, and the specific calculation process can be shown in the following formula (4):

[0095] δ f = δ h / i (4)

[0096] The first expression for representing the front wheel angle of the vehicle is determined in this way, and embodiments of the present application are not limited.

[0097] Step S113, determining a second expression based on the first expression through the target motion model;

[0098] Wherein the second expression is used to represent the target angular velocity gain.

[0099] The step can be understood as determining, based on the first expression for representing the front wheel angle of the vehicle, a second expression for representing a target angular velocity gain through a target motion model.

[0100] Exemplarily, the first expression and the formula (3) can be substituted into the target motion model, i.e., the formulas (1)-(2), to obtain the second expression for representing the target angular velocity gain, and the specific expression form can be shown in the following formula (5):

[0101]

[0102] The second expression for representing the target angular velocity gain is thus determined, and embodiments of the present application are not limited.

[0103] Optionally, in step S12, determining the target relationship based on the user data can include the following execution steps:

[0104] In step S120, in response to the vehicle speed being greater than a first vehicle speed threshold and less than or equal to a second vehicle speed threshold, the target angular velocity gain is controlled to be unchanged based on the user data, to obtain a first target relationship; or,

[0105] The first vehicle speed threshold can be understood as a minimum speed threshold for representing that the vehicle is in a driving state, which can be 0 km / h for example, and embodiments of the present application are not limited. The second vehicle speed threshold can be understood as a maximum speed threshold for representing that the vehicle is in a low-speed driving state, which can be 60 km / h for example, and embodiments of the present application are not limited.

[0106] The step can be understood as that when the vehicle speed is greater than the first vehicle speed threshold and less than or equal to the second vehicle speed threshold, i.e., the vehicle speed is greater than the minimum speed threshold for representing that the vehicle is in a driving state and less than or equal to the maximum speed threshold for representing that the vehicle is in a low-speed driving state, it indicates that the vehicle is currently in a low-speed driving state, and at this time, the target angular velocity gain is controlled to be unchanged based on the user data for representing the driving habit of the user, to obtain the first target relationship.

[0107] Exemplarily, when the vehicle speed is greater than 0 km / h and less than or equal to 60 km / h, it indicates that the vehicle is currently in a low-speed driving state, and at this time, the target angular velocity gain is controlled to be unchanged based on the user data for representing the driving habit of the user, to obtain the first target relationship, and embodiments of the present application are not limited.

[0108] In step S121, in response to the vehicle speed being greater than the second vehicle speed threshold, the target angular velocity gain is controlled to be reduced based on the user data, to obtain a second target relationship.

[0109] The step can be understood as: when the vehicle speed is greater than the maximum speed threshold value for indicating that the vehicle is in a low-speed driving state, it indicates that the vehicle is currently in a medium-high-speed driving state, and the target angular velocity gain is reduced based on the user data for indicating the driving habit of the user to obtain a second target relationship.

[0110] Exemplarily, when the vehicle speed is greater than 60km / h, it indicates that the vehicle is currently in a medium-high-speed driving state, and the target angular velocity gain is reduced based on the user data for indicating the driving habit of the user to obtain a second target relationship, and the embodiments of the present application are not limited thereto.

[0111] Figure 3 is a schematic diagram of determining a target relationship according to an embodiment of the present application, as shown in Figure 3 , the specific implementation process of the above steps is comprehensively described, Figure 3 the horizontal axis represents the vehicle speed, and the vertical axis represents the target angular velocity gain; when the vehicle speed is greater than 0km / h and less than or equal to 60km / h, the target angular velocity gain is unchanged; and when the vehicle speed is greater than 60km / h, the target angular velocity gain is reduced, thereby ensuring the effects of vehicle sensitivity at low speed and stability at high speed.

[0112] Figure 4 is a schematic diagram of determining a target transmission ratio according to an embodiment of the present application, as shown in Figure 4 , after determining the target relationship for indicating the relationship between the angular velocity gain and the vehicle speed, i.e., the above Figure 3 , the specific process of determining the target transmission ratio based on the target angular velocity gain and the target relationship can be as shown in Figure 4 , the target transmission ratio changes with the vehicle speed, and the change range is between 2-25, thereby meeting the needs of vehicle sensitivity at low speed and stability at high speed.

[0113] It can be understood that in the case of deceleration, if the steering wheel angle is unchanged or the steering wheel angle is increased, the wheel angle will be further increased, which will cause the wheel angle to have a tendency to “turn inwards”, i.e., a self-steering effect is generated. Specifically, the steering wheel angle input can be divided into two different speed domains, and the steering wheel angle range is 0-20deg, Figure 5 is a schematic diagram of the change of the steering wheel angle with time according to an embodiment of the present application, as shown in Figure 5 , the steering wheel angle input range is controlled to be 0-20deg, and when the vehicle speed starts to decrease in the two different speed domains, the corresponding wheel angle changes differently.

[0114] Fig. 6(a) is a schematic diagram of vehicle speed variation according to an embodiment of the present application. As shown in Fig. 6(a), a vehicle speed domain of 55 km / h-10 km / h is represented, i.e. the vehicle starts to decelerate from 55 km / h at a constant deceleration to 10 km / h. Fig. 6(b) is a schematic diagram of wheel rotation angle variation with vehicle speed according to an embodiment of the present application. As shown in Fig. 6(b), the corresponding wheel rotation angle variation when the vehicle speed is constantly reduced from 55 km / h to 10 km / h is represented.

[0115] Fig. 7(a) is a schematic diagram of vehicle speed variation according to another embodiment of the present application. As shown in Fig. 7(a), a vehicle speed domain of 100 km / h-55 km / h is represented, i.e. the vehicle starts to decelerate from 100 km / h at a constant deceleration to 55 km / h. Fig. 7(b) is a schematic diagram of wheel rotation angle variation with vehicle speed according to an embodiment of the present application. As shown in Fig. 7(b), the corresponding wheel rotation angle variation when the vehicle speed is constantly reduced from 100 km / h to 55 km / h is represented.

[0116] As can be seen from Figs. 6-7, within the speed range of 100 km / h-55 km / h, the wheel rotation angle increases with the decrease of vehicle speed, but the increase is not large, mainly because the rotation ratio is overall large and the transmission ratio changes little within this speed range. Within the speed range of 55 km / h-10 km / h, the wheel rotation angle increases with the decrease of vehicle speed, and the increase is large, mainly because the rotation ratio is overall small and the vehicle speed changes greatly within this speed range, which produces a "self-steering effect".

[0117] Optionally, in step S13, the following execution step can also be included:

[0118] In step S130, the first vehicle speed is determined in response to the acceleration of the vehicle being greater than a first acceleration threshold.

[0119] The first acceleration threshold can be understood as a minimum acceleration threshold for indicating that the vehicle decelerates fast, for example, can be 1.5 m / s 2 The first vehicle speed can be understood as the real-time vehicle speed.

[0120] This step can be understood as when the acceleration of the vehicle is greater than the minimum acceleration threshold for indicating that the vehicle decelerates fast, it indicates that the vehicle is currently in a state of rapid deceleration, at which time the current vehicle speed is recorded, i.e. the first vehicle speed is determined.

[0121] For example, when the rate of deceleration of the vehicle is greater than 1.5 m / s 2 , it indicates that the vehicle is currently in a state of rapid deceleration, at which time the current vehicle speed is recorded, i.e. the first vehicle speed is determined. The embodiments of the present application are not limited in this regard.

[0122] Step S131, determining the first transmission ratio corresponding to the first vehicle speed according to the first vehicle speed;

[0123] The first transmission ratio corresponds to the first steering angle.

[0124] This step can be understood as determining the first transmission ratio corresponding to the current vehicle speed according to the current vehicle speed when the acceleration of the vehicle is greater than the minimum acceleration threshold value for indicating that the vehicle reduces speed quickly after determining the current vehicle speed.

[0125] It can be understood that when the acceleration of the vehicle is greater than the minimum acceleration threshold value for indicating that the vehicle reduces speed quickly, it indicates that the vehicle is currently in a state of rapid deceleration, and the first transmission ratio corresponding to the current vehicle speed is determined at this time. The first transmission ratio corresponds to the first steering angle.

[0126] Step S132, controlling the steering angle of the vehicle to be the first steering angle.

[0127] This step can be understood as controlling the steering angle of the vehicle to be the first steering angle corresponding to the first transmission ratio, so as to reduce the self-steering effect in the case of vehicle deceleration.

[0128] Optionally, in step S13, the following execution step can also be included:

[0129] Step S133, when the steering angle of the vehicle is the first steering angle, the steering angle of the vehicle is controlled based on the target angular velocity gain and the target relationship in response to the vehicle speed meeting the first preset condition and the steering wheel angle meeting the second preset condition, or the vehicle speed being greater than the first vehicle speed.

[0130] The first preset condition can be understood as a state for indicating that the vehicle speed is zero, and the second preset condition can be understood as a state for indicating that the steering wheel angle of the vehicle is zero. This step can be understood as when the steering angle of the vehicle is the first steering angle, when the vehicle speed is zero and the steering wheel angle is zero, or the vehicle speed is greater than the above recorded current vehicle speed, it indicates that the vehicle is not in a state of rapid deceleration. At this time, the steering angle of the vehicle is controlled based on the target angular velocity gain and the target relationship.

[0131] Figure 8(a) is a diagram showing the change of front wheel steering angle over time after the steps S130-S133 are performed within the speed threshold of 100km / h to 55km / h according to one embodiment of the present application, Figure 8(b) is a diagram showing the change of yaw rate over time after the steps S130-S133 are performed within the speed threshold of 100km / h to 55km / h according to one embodiment of the present application, Figure 8(c) is a diagram showing the change of side slip angle over time after the steps S130-S133 are performed within the speed threshold of 100km / h to 55km / h according to one embodiment of the present application.

[0132] Figure 9(a) is a diagram showing the change of front wheel steering angle over time after the steps S130-S133 are performed within the speed threshold of 55km / h to 10km / h according to another embodiment of the present application, Figure 9(b) is a diagram showing the change of yaw rate over time after the steps S130-S133 are performed within the speed threshold of 55km / h to 10km / h according to another embodiment of the present application, Figure 9(c) is a diagram showing the change of side slip angle over time after the steps S130-S133 are performed within the speed threshold of 55km / h to 10km / h according to another embodiment of the present application.

[0133] From the above Figures 8-9, it can be seen that, in any speed range, the control strategy can effectively reduce the wheel steering angle, yaw rate, and side slip angle, ensuring the stability of the vehicle required by the driver during deceleration and rapid deceleration.

[0134] In the medium-high speed range of 100km / h to 55km / h, the wheel steering angle, yaw rate, and side slip angle change slightly, because the steering ratio of the steer-by-wire system is inherently stable in the medium-high speed range.

[0135] In the medium-low speed range of 55km / h to 10km / h, the wheel steering angle, yaw rate, and side slip angle change significantly, and the control strategy can effectively reduce these indicators, because the steering ratio of the steer-by-wire system is inherently sensitive in the medium-low speed range, and is even more sensitive at low speeds. During deceleration, if the sensitivity of the switch is too fast, it will cause an unintended self-steering effect, and the control strategy can effectively reduce this effect.

[0136] Those skilled in the art can clearly understand that the method according to the above-mentioned embodiments can be realized by means of software and necessary general hardware platforms, of course, can also be realized by hardware, but in many cases, the former is a better embodiment. Based on such understanding, the technical solutions of the present application can be embodied in the form of a software product, which is stored in a storage medium (such as a ROM / RAM, a magnetic disk, an optical disk) and includes a plurality of instructions for causing a terminal device (which can be a mobile phone, a computer, a server, or a network device) to execute the method described in the embodiments of the present application.

[0137] In the embodiment, a device for controlling a steering angle of a vehicle based on a steer-by-wire transmission ratio is also provided, which is used to implement the above-mentioned embodiments and preferred embodiments, and will not be described again. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware, or a combination of software and hardware is also possible and contemplated.

[0138] Figure 10 is a structural block diagram of a device for controlling a steering angle of a vehicle based on a steer-by-wire transmission ratio according to one of the embodiments of the present application, as Figure 10 shown, a device 1000 for controlling a steering angle of a vehicle based on a steer-by-wire transmission ratio is exemplified, which comprises: an acquisition module 1001, the acquisition module 1001 is used to acquire vehicle data and user data, wherein the vehicle data is used to represent the steering angle information and motion information of the vehicle in the driving process, and the user data is used to represent the driving habit of the user; a first determination module 1002, the first determination module 1002 is used to determine a target angular velocity gain of the vehicle based on the vehicle data; a second determination module 1003, the second determination module 1003 is used to determine a target relationship based on the user data, wherein the target relationship is used to represent the relationship between the angular velocity gain and the vehicle speed; a third determination module 1004, the third determination module 1004 is used to determine a target transmission ratio based on the target angular velocity gain and the target relationship, wherein the target transmission ratio corresponds to the vehicle speed; and a control module 1005, the control module 1005 is used to control the steering angle of the vehicle based on the target transmission ratio.

[0139] Optionally, the first determination module 1002 is further used to acquire a vehicle mechanics relationship, wherein the vehicle mechanics relationship is used to represent the balance relationship between the force and the torque of the vehicle; and the vehicle data is multiplied according to the vehicle mechanics relationship, to obtain a target motion model.

[0140] Optionally, the first determining module 1002 is further configured to determine a first expression based on a steering wheel angle of the vehicle and an initial transmission ratio, where the first expression is used to represent a front wheel angle of the vehicle; determine a second expression based on the target motion model and the first expression, where the second expression is used to represent a target angular velocity gain.

[0141] Optionally, the second determining module 1003 is further configured to, in response to the vehicle speed being greater than the first vehicle speed threshold and less than or equal to the second vehicle speed threshold, determine that the target angular velocity gain is controlled based on the user data to be constant, to obtain a first target relationship; or, in response to the vehicle speed being greater than the second vehicle speed threshold, determine that the target angular velocity gain is controlled based on the user data to decrease, to obtain a second target relationship.

[0142] Optionally, the third determining module 1003 is further configured to, in response to an acceleration of the vehicle being greater than a first acceleration threshold, determine a first vehicle speed; determine a first transmission ratio corresponding to the first steering angle according to the first vehicle speed, where the first transmission ratio corresponds to the first steering angle; and control the steering angle of the vehicle to be the first steering angle.

[0143] Optionally, the third determining module 1003 is further configured to, when the steering angle of the vehicle is the first steering angle, in response to the vehicle speed meeting a first preset condition and the steering wheel angle meeting a second preset condition, or the vehicle speed being greater than a first vehicle speed, control the steering angle of the vehicle based on the target angular velocity gain and the target relationship.

[0144] It should be noted that the above modules can be implemented by software or hardware, and for the latter, the following implementation manners can be used, but are not limited thereto: all the modules are located in the same processor; or the modules are located in different processors in any combination.

[0145] Embodiments of the present application also provide a vehicle for executing the steps in any of the above method embodiments.

[0146] Optionally, in the present embodiment, the vehicle can be configured to store a computer program for executing the following steps:

[0147] Step S1, obtaining vehicle data and user data;

[0148] Step S2, determining a target angular velocity gain of the vehicle based on the vehicle data;

[0149] Step S3, determining a target relationship based on the user data;

[0150] Step S4, determining a target transmission ratio based on the target angular velocity gain and the target relationship;

[0151] Step S5, controlling a steering angle of the vehicle based on the target transmission ratio.

[0152] The embodiment of the present application also provides a computer readable storage medium, wherein the storage medium stores a computer program, and the computer program is configured to execute the steps in any one of the method embodiments when running on a computer or a processor.

[0153] Optionally, in the embodiment, the computer readable storage medium is configured to store the computer program for executing the following steps.

[0154] Step S1, obtaining vehicle data and user data;

[0155] Step S2, determining a target angular velocity gain of the vehicle based on the vehicle data;

[0156] Step S3, determining a target relationship based on the user data;

[0157] Step S4, determining a target transmission ratio based on the target angular velocity gain and the target relationship;

[0158] Step S5, controlling a steering angle of the vehicle based on the target transmission ratio.

[0159] Optionally, in the embodiment, the computer readable storage medium can include but is not limited to a U disk, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk and various storage media that can store computer programs.

[0160] The embodiment of the present application also provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is configured to execute the computer program to execute the steps in any one of the method embodiments.

[0161] Optionally, in the embodiment, the processor in the electronic device is configured to execute the computer program to execute the following steps.

[0162] Step S1, obtaining vehicle data and user data;

[0163] Step S2, determining a target angular velocity gain of the vehicle based on the vehicle data;

[0164] Step S3, determining a target relationship based on the user data;

[0165] Step S4, determining a target transmission ratio based on the target angular velocity gain and the target relationship;

[0166] Step S5, controlling a steering angle of the vehicle based on the target transmission ratio.

[0167] Optionally, the specific examples in the embodiments can refer to the examples described in the above embodiments and optional implementation manners, and the embodiments will not be described here again.

[0168] The serial numbers of the above embodiments of the application are only for description, and do not represent the advantages and disadvantages of the embodiments.

[0169] In the above embodiments of the application, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0170] In several embodiments provided in the present application, it should be understood that the disclosed technical contents can be implemented by other manners. Among them, the above-described device embodiments are only schematic, for example, the division of the units can be a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units or modules shown or discussed can be indirect coupling or communication connection through some interfaces, units or modules, which can be electrical or other forms.

[0171] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed to multiple units. According to actual needs, part or all of the units can be selected to achieve the purpose of the embodiment scheme.

[0172] In addition, each functional unit in each embodiment of the application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The above integrated unit can be realized in the form of hardware, or in the form of software functional unit.

[0173] The integrated unit, if implemented in the form of a software function unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application, essentially or in other words, the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a number of instructions to make a computer device (which can be a personal computer, a server or a network device, etc.) execute all or part of the steps of the methods described in various embodiments of the present application. The aforementioned storage medium includes: a U disk, a read-only memory (Read-Only Memory, ROM), a random access memory (Random Access Memory, RAM), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store program codes.

[0174] The above is only the preferred embodiment of the present application, it should be pointed out that, for those skilled in the art, without departing from the principles of the present application, can make a number of improvements and refinements, these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A method of controlling a steering angle of a vehicle based on a steer-by- wire transmission ratio, characterized by, The method comprises: acquiring vehicle data and user data, wherein the vehicle data is used to represent cornering information and motion information of a vehicle during driving, and at least includes a steering wheel cornering angle of the vehicle and an initial transmission ratio of the vehicle, and the user data is used to represent driving habits of a user; determining a target angular velocity gain of the vehicle based on the vehicle data; determining a target relationship based on the user data, wherein the target relationship is used to represent a relationship between an angular velocity gain and a vehicle speed; determining a target transmission ratio based on the target angular velocity gain and the target relationship, wherein the target transmission ratio corresponds to the vehicle speed; controlling a steering angle of the vehicle based on the target transmission ratio; the determining of the target angular velocity gain of the vehicle based on the vehicle data comprises: acquiring a vehicle mechanics relationship, wherein the vehicle mechanics relationship is used to represent a balance relationship between force and torque of the vehicle; performing a product operation on the vehicle data according to the vehicle mechanics relationship to obtain a target motion model; determining a first expression based on the steering wheel cornering angle of the vehicle and the initial transmission ratio, wherein the first expression is used to represent a front wheel cornering angle of the vehicle; determining a second expression based on the first expression through the target motion model, wherein the second expression is used to represent the target angular velocity gain; wherein the determining of the target relationship based on the user data comprises: in response to the vehicle speed being greater than a first vehicle speed threshold and less than or equal to a second vehicle speed threshold, controlling the target angular velocity gain to be unchanged based on the user data to obtain a first target relationship; or in response to the vehicle speed being greater than the second vehicle speed threshold, controlling the target angular velocity gain to decrease based on the user data to obtain a second target relationship.

2. The method of claim 1, wherein, Further comprising: determining a first vehicle speed in response to an acceleration of the vehicle being greater than a first acceleration threshold; determining a first transmission ratio corresponding to the first steering angle according to the first vehicle speed, wherein the first transmission ratio corresponds to the first steering angle; controlling the steering angle of the vehicle to be the first steering angle.

3. The method of claim 2, wherein, Further comprising: when the steering angle of the vehicle is the first steering angle, controlling the steering angle of the vehicle based on the target angular velocity gain and the target relationship in response to the vehicle speed meeting a first preset condition and the steering wheel cornering angle meeting a second preset condition, or the vehicle speed being greater than the first vehicle speed.

4. A device for controlling the steering angle of a vehicle based on the steer-by-wire transmission ratio, characterized in that, The method comprises: an acquisition module, configured to acquire vehicle data and user data, wherein the vehicle data is used to represent cornering information and motion information of a vehicle during driving, and at least includes a steering wheel cornering angle of the vehicle and an initial transmission ratio of the vehicle, and the user data is used to represent driving habits of a user; a first determination module, configured to determine a target angular velocity gain of the vehicle based on the vehicle data; a second determination module, configured to determine a target relationship based on the user data, wherein the target relationship is used to represent a relationship between an angular velocity gain and a vehicle speed; a third determining module configured to determine a target transmission ratio based on the target angular velocity gain and the target relationship, wherein the target transmission ratio corresponds to the vehicle speed; a control module configured to control a steering angle of the vehicle based on the target transmission ratio; the first determining module is further configured to obtain a vehicle mechanics relationship, wherein the vehicle mechanics relationship is used to represent a balance relationship between force and torque of the vehicle; perform a product operation on the vehicle data according to the vehicle mechanics relationship to obtain a target motion model; determine a first expression based on a steering wheel angle of the vehicle and the initial transmission ratio, wherein the first expression is used to represent a front wheel steering angle of the vehicle; determine a second expression based on the first expression through the target motion model, wherein the second expression is used to represent the target angular velocity gain; the second determining module is further configured to, in response to the vehicle speed being greater than a first vehicle speed threshold and less than or equal to a second vehicle speed threshold, control the target angular velocity gain to be unchanged based on the user data to obtain a first target relationship; or, in response to the vehicle speed being greater than the second vehicle speed threshold, control the target angular velocity gain to decrease based on the user data to obtain a second target relationship.

5. A vehicle characterized by comprising: The vehicle is configured to perform the method of controlling a vehicle steering angle based on a steer-by-wire transmission ratio according to any one of claims 1 to 3.

6. A computer-readable storage medium, characterized in that, The computer readable storage medium stores a computer program, wherein the computer program is configured to perform the method of controlling a vehicle steering angle based on a steer-by-wire transmission ratio according to any one of claims 1 to 3 when running on a computer or a processor. 7.An electronic device comprising a memory and a processor, the electronic device characterized by, The memory stores a computer program, and the processor is configured to run the computer program to perform the method of controlling a vehicle steering angle based on a steer-by-wire transmission ratio according to any one of claims 1 to 3.

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