Vehicle steering control method, electronic device, and storage medium

Abstract

The application relates to the technical field of vehicles and discloses a vehicle steering control method, an electronic device and a storage medium, which comprises the following steps: acquiring a current driving state of a vehicle, and entering a preset steering control mode when the current driving state is a preset steering state; in the preset steering control mode, a front wheel of the vehicle is controlled to steer in a first direction at a target steering angle, and a rear wheel of the vehicle is controlled to steer in a second direction at a preset steering angle, the first direction being opposite to the second direction; if a change in a current opening degree of an accelerator pedal of the vehicle is detected, a torque change amount is determined according to an opening degree change amount of the accelerator pedal, a torque increase amount is distributed to a driving torque of a front axle driving motor, or a torque decrease amount is distributed to an energy recovery torque of the front axle driving motor, and the torque of a rear axle driving motor is maintained. Therefore, based on the above mode, steering with a smaller steering radius of the vehicle can be realized under the premise of ensuring the lateral stability of the vehicle.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, specifically to a vehicle steering control method, electronic device, and storage medium. Background Technology

[0002] With the continuous advancement of vehicle drive technology, the application of distributed electric drive systems is becoming increasingly widespread. In distributed electric drive systems, key components such as drive motors, reducers, and controllers are distributed across multiple parts of the vehicle (such as the wheel wells or wheel hubs). By independently controlling the torque and speed of each wheel, this system can achieve more efficient power distribution and precise dynamic control.

[0003] Currently, although vehicles using distributed electric drive systems are more flexible in terms of control, their turning radius is still relatively large in scenarios where the vehicle turns at a large angle, resulting in insufficient flexibility and lateral stability during the turning process. Summary of the Invention

[0004] In view of the above problems, this application provides a vehicle steering control method, electronic device and storage medium, which distributes the torque change to the front axle drive motor during rear wheel anti-steering process, thereby achieving a small steering radius while ensuring the lateral stability of the vehicle.

[0005] The first aspect of this application provides a vehicle steering control method, comprising: acquiring the current driving state of the vehicle, and entering a preset steering control mode when the current driving state is a preset steering state; in the preset steering control mode, controlling the front wheels of the vehicle to steer in a first direction with a target turning angle, and controlling the rear wheels of the vehicle to steer in a second direction with a preset turning angle; wherein the first direction and the second direction are opposite; if a change in the current opening of the accelerator pedal is detected, determining the torque change based on the change in the opening of the accelerator pedal, allocating the torque increase to the driving torque of the front axle drive motor, or allocating the torque decrease to the energy recovery torque of the front axle drive motor, and maintaining the torque of the rear axle drive motor; wherein the change in the opening of the accelerator pedal and the torque change have a preset correspondence.

[0006] In some specific embodiments, the step of controlling the rear wheels of the vehicle to steer in a second direction at a preset angle includes: obtaining the current required torque value of the driver; controlling the first drive motor corresponding to the outer wheel of the rear axle of the vehicle to output the current required torque value, and controlling the second drive motor corresponding to the inner wheel of the rear axle of the vehicle to output a negative current required torque value.

[0007] In some specific embodiments, if a change in the current opening of the vehicle's accelerator pedal is detected, the torque change is determined based on the change in accelerator pedal opening. The increased torque is then allocated to the drive torque of the front axle drive motor, or the decreased torque is allocated to the energy recovery torque of the front axle drive motor. After maintaining the torque of the rear axle drive motor, the method further includes: acquiring the vehicle's current speed and current control parameters; wherein the current control parameters are generated by the driver's control behavior; determining the vehicle's current driving state based on the current speed and current control parameters; and exiting the preset steering control mode if the current driving state does not conform to the preset steering state.

[0008] In some specific embodiments, the current control parameters include: the current steering angle of the vehicle's steering wheel and the current opening of the brake pedal.

[0009] In some specific embodiments, the step of determining the current driving state of the vehicle based on the current vehicle speed and current control parameters, and exiting the preset steering control mode when the current driving state does not meet the preset steering state, includes: if any one of the following is satisfied: the current vehicle speed is greater than the preset vehicle speed, the current steering wheel angle is less than the preset steering angle, and the current brake pedal opening is greater than the preset opening, then it is determined that the current driving state does not meet the preset steering state, and the preset steering control mode is exited.

[0010] In some specific embodiments, the method further includes: obtaining the current master cylinder pressure and the current push rod stroke of the vehicle, and determining a first current opening degree corresponding to the current master cylinder pressure and a second current opening degree corresponding to the current push rod stroke; taking the smaller of the first current opening degree and the second current opening degree as the current opening degree of the vehicle's brake pedal.

[0011] In some specific embodiments, the step of obtaining the current driving state of the vehicle and entering the preset steering control mode when the current driving state is a preset steering state includes: obtaining the current vehicle speed, the current steering wheel angle, the driver's current required torque, and the current fault level of the drive motor; when the current vehicle speed is within the preset speed range, the absolute value of the current steering angle is greater than a preset ratio of the maximum steering angle, the current required torque is less than the preset required torque, and the current fault level is lower than the preset fault level, the current driving state is determined to be a preset steering state, and the preset steering control mode is entered.

[0012] In some specific embodiments, after obtaining the current driving state of the vehicle and entering the preset steering control mode when the current driving state is a preset steering state, the method further includes: if the vehicle is in a preset slip condition, then entering the preset chassis control mode; in the preset chassis control mode, after controlling the current yaw moment of the vehicle to be reduced to zero and the current slip ratio to be reduced to the target slip ratio, then entering the preset steering control mode.

[0013] A second aspect of this application provides an electronic device, comprising: a processor; and a memory for storing a computer program, wherein the computer program, when executed by the processor, implements the vehicle steering control method described above.

[0014] A third aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the vehicle steering control method as described above.

[0015] The beneficial technical effects of this application are at least as follows: Based on the vehicle steering control method, electronic device, and storage medium provided in this application, the method includes: acquiring the current driving state of the vehicle, and entering a preset steering control mode when the current driving state is a preset steering state; in the preset steering control mode, controlling the front wheels of the vehicle to steer in a first direction with a target turning angle, and controlling the rear wheels of the vehicle to steer in a second direction with a preset turning angle; wherein the first direction and the second direction are opposite; if a change in the current opening of the accelerator pedal is detected, determining the torque change based on the change in the accelerator pedal opening, allocating the torque increase to the driving torque of the front axle drive motor, or allocating the torque decrease to the energy recovery torque of the front axle drive motor, and maintaining the torque of the rear axle drive motor; wherein the change in the accelerator pedal opening and the torque change have a preset correspondence. Therefore, during the rear wheel anti-directional steering process, allocating the torque change to the front axle drive motor can achieve steering with a smaller turning radius while ensuring the lateral stability of the vehicle.

[0016] The above description is merely an overview of the technical solutions of the embodiments of this application. In order to better understand the technical means of the embodiments of this application and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of this application more obvious and understandable, specific implementation methods of this application are described below. Attached Figure Description

[0017] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0018] Figure 1 This is a flowchart illustrating an embodiment of the vehicle steering control method provided in this application;

[0019] Figure 2 This is a flowchart illustrating another embodiment of the vehicle steering control method provided in this application;

[0020] Figure 3 This is a schematic diagram of a vehicle turning left using the vehicle steering control method provided in this application;

[0021] Figure 4 This is a schematic diagram of a vehicle turning right using the vehicle steering control method provided in this application;

[0022] Figure 5 This is a flowchart illustrating yet another embodiment of the vehicle steering control method provided in this application;

[0023] Figure 6 This is a flowchart illustrating yet another embodiment of the vehicle steering control method provided in this application;

[0024] Figure 7 This is a flowchart illustrating yet another embodiment of the vehicle steering control method provided in this application;

[0025] Figure 8 This is a flowchart illustrating yet another embodiment of the vehicle steering control method provided in this application;

[0026] Figure 9 This is a schematic diagram of the structural framework of an embodiment of the electronic device provided in this application;

[0027] Figure 10 This is a schematic diagram of the structural framework of an embodiment of the computer-readable storage medium provided in this application. Detailed Implementation

[0028] Exemplary embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited to the embodiments set forth herein. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without inventive effort are within the scope of protection of the present application.

[0029] If the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Furthermore, if the word "and / or" appears throughout the text, it means including three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0030] The first aspect of this application provides a vehicle steering control method. Figure 1This is a schematic flowchart of an embodiment of the vehicle steering control method provided in this application. (In conjunction with...) Figure 1 This method includes the following steps:

[0031] S101: Obtain the current driving status of the vehicle, and enter the preset steering control mode when the current driving status is the preset steering status.

[0032] It should be understood that the current driving state of a vehicle can include parameters such as vehicle control parameters, motion parameters, and driving scenario parameters. Among them, control parameters can include the accelerator pedal opening, brake pedal opening, and steering wheel angle operated by the driver, while motion parameters can include vehicle speed, acceleration, yaw rate, and wheel speed, and driving scenario parameters can include road surface adhesion coefficient, gradient, and curve curvature, etc., without specific limitations.

[0033] The preset steering state can be pre-set according to vehicle driving safety and steering flexibility requirements, such as a low-speed, large-angle U-turn state or a steering avoidance state in narrow road sections. In this embodiment, by comprehensively judging whether the above parameters meet the preset conditions, it is determined whether the current driving state meets the preset steering state, and then it is determined whether to activate the preset steering control mode to meet the specific steering control requirements of the vehicle in a specific scenario. For example, when the vehicle is driving at low speed and the steering wheel angle exceeds the preset large-angle threshold, and the road surface adhesion coefficient is high, indicating that the road surface condition is good and suitable for flexible steering, the system can determine that the current driving state meets the preset steering state.

[0034] S102: In the preset steering control mode, the front wheels of the vehicle are controlled to steer in the first direction with a target turning angle, and the rear wheels of the vehicle are controlled to steer in the second direction with a preset turning angle; wherein the first direction and the second direction are opposite.

[0035] In summary, once the vehicle enters the preset steering control mode, it achieves steering control through the corresponding steering control strategy. Specifically, the front and rear wheels steer in opposite directions to achieve the vehicle's minimum turning radius. When the driver controls the front wheels to steer in the first direction at a target angle, the vehicle can automatically control the rear wheels to steer in the second direction at a preset angle.

[0036] In some applications, when a driver maneuvers the steering wheel to turn the front wheels to the left (first direction) and controls the rear wheels to turn to the right (second direction), they achieve opposite-direction steering. This opposite-direction steering method shortens the vehicle's turning trajectory diameter. It should be understood that opposite-direction steering is a steering method where the front and rear wheels turn in opposite directions. The target steering angle of the front wheels can be calculated based on parameters such as the driver's input steering wheel angle signal, current vehicle speed, and wheelbase, using the steering ratio to ensure the front wheel steering angle meets the driver's steering intention. Here's a specific example of calculating the target steering angle of the front wheels: Assume the vehicle wheelbase is L, the steering wheel angle is δ, the steering ratio is i, and the current vehicle speed is V. According to the Ackermann steering geometry principle, the target steering angle θ of the front wheels can be calculated using the formula θ = arctan(L / (i * δ * k)), where k is a speed-related correction coefficient used to adjust steering sensitivity at different speeds. For example, a larger k value at lower speeds makes steering more sensitive, while a smaller k value at higher speeds ensures steering stability. The preset steering angle of the rear wheels can be determined in advance, and its absolute value is usually smaller than the target steering angle of the front wheels to avoid oversteering and vehicle instability. For example, the preset steering angle can be set to the maximum steering angle of the rear wheels, such as 12°.

[0037] During steering, the vehicle uses angle sensors installed in the steering system to monitor the actual steering angles of the front and rear wheels in real time. These actual angles are compared to the corresponding target and preset steering angles. If a deviation exists, the steering motor drives the steering tie rod or steering knuckle to adjust the angle, ensuring the actual steering angle always tracks the target value and thus guaranteeing steering accuracy. For example, if a 5° deviation is detected between the actual front wheel angle and the target angle, the system immediately instructs the steering motor to adjust the length of the steering tie rod or the angle of the steering knuckle to quickly correct the front wheel angle and ensure it accurately reaches the target angle. Similarly, if the actual rear wheel angle deviates from the preset angle by 3°, the system will respond quickly, adjusting the rear wheel steering mechanism accordingly to maintain accurate steering at the preset angle.

[0038] S103: If a change in the current opening of the accelerator pedal is detected, the torque change is determined based on the change in the accelerator pedal opening. The torque increase is allocated to the drive torque of the front axle drive motor, or the torque decrease is allocated to the energy recovery torque of the front axle drive motor, while maintaining the torque of the rear axle drive motor. The change in the accelerator pedal opening and the torque change have a preset correspondence.

[0039] It should be understood that when the vehicle is in a preset steering state, the driver may change the current opening of the accelerator pedal according to the actual driving conditions, such as increasing or decreasing the current opening. A change in the current opening of the accelerator pedal indicates a change in the demand for vehicle drive torque, at which point the torque of the drive motor needs to be adjusted to meet the new demand.

[0040] In this embodiment, since the vehicle is in a preset steering control mode, the steering state of the rear wheels is crucial to the vehicle's lateral stability. Adjusting the torque of the rear axle drive motor simultaneously could affect the steering torque balance of the rear wheels due to torque changes, thereby interfering with the vehicle's steering trajectory and stability. Therefore, this embodiment allocates only the torque change caused by the accelerator pedal opening to the front axle drive motor. This separate adjustment of the front axle torque responds to the driver's power demands while keeping the torque of the rear axle drive motor constant, ensuring stable rear wheel steering and avoiding additional interference with the vehicle's attitude control during steering. This control method achieves reasonable torque distribution, satisfying the driver's power requests while maximizing the stability and accuracy of vehicle steering in the preset steering control mode.

[0041] Specifically, if a change in the current accelerator pedal opening is detected, the system queries the initial torque change corresponding to the current opening change based on a pre-stored mapping between opening and torque changes in the vehicle control system. When establishing this mapping, the torque change is calculated based on the accelerator pedal opening change, further corrected by considering the current battery SOC value, motor efficiency map, and mechanical loss parameters of the transmission system. For example, when the accelerator pedal opening increases by 5%, the system first determines the initial torque increment based on the pre-stored opening-torque mapping table, and then further corrects the initial torque increment using various parameters to obtain the corresponding torque change.

[0042] Specifically, allocating the increased torque to the front axle drive motor enhances the front axle's driving force output, meeting the driver's demand for increased power. Allocating the decreased torque to the energy recovery torque of the front axle drive motor effectively reduces the actual driving torque of the front axle by increasing energy recovery intensity, achieving precise downward adjustment of power output. During torque allocation, the system can monitor the current operating status of the front axle drive motor in real time, including parameters such as motor speed, temperature, and current. If certain parameters approach thresholds (e.g., motor temperature nearing a protection threshold), the allocation ratio of the torque change can be appropriately reduced to prioritize the safe operation of the motor. An example of appropriately reducing the allocation ratio of the torque change is as follows: Assuming the originally planned torque increase is ΔT, when the motor temperature is detected to be close to the protection threshold, the system can adjust the actual allocated torque increase to a smaller value such as 0.8ΔT or 0.6ΔT. The specific adjustment ratio can be dynamically determined based on the motor's current temperature, speed, and other actual state parameters. Similarly, in cases of reduced torque, if the motor is operating under high load, the amount of energy recovery torque can be appropriately reduced to avoid excessive reverse current generated by the motor due to excessive energy recovery, which could damage the motor.

[0043] In some applications, energy recovery can be controlled by considering the current state of the brake pedal. For example, if the brake pedal is detected to be engaged, the increase in energy recovery torque can be paused to avoid interference with the service braking system and ensure the smoothness and safety of the torque adjustment process. For instance, when the driver presses the brake pedal, the vehicle control system immediately detects the braking signal and pauses the allocation of the reduced torque to the energy recovery torque of the front axle drive motor. At this point, the system prioritizes responding to the brake pedal command, using the service braking system to decelerate the vehicle, preventing the reverse torque generated by energy recovery from conflicting with the braking system and avoiding prolonged braking distance or uneven braking.

[0044] It should be understood that there can be one or two front axle drive motors. When two front axle drive motors are used, the increase or decrease in torque can be more flexibly distributed between the two motors. For example, when the vehicle is making a large-angle turn, more of the torque increase can be distributed to the drive motor corresponding to the outer front wheel to enhance the driving force of the outer wheel and help the vehicle complete the steering action more smoothly. When precise control of power output is required, the torque change can be evenly distributed between the two front axle drive motors to ensure the smoothness of vehicle driving.

[0045] Figure 2 This is a flowchart illustrating another embodiment of the vehicle steering control method provided in this application.

[0046] Combination Figure 2In some specific embodiments, the step of controlling the rear wheels of the vehicle to steer in a second direction at a preset angle includes:

[0047] S201: Obtain the driver's current torque requirement.

[0048] The driver's current torque demand value can be calculated based on the current accelerator pedal opening and other parameters (such as the current vehicle speed). For example, by querying a preset correspondence table of accelerator pedal opening and torque demand, and by correcting the base torque value in the mapping table in combination with the current vehicle speed, the final current torque demand value can be obtained.

[0049] For example, assuming the accelerator pedal opening is 20%, in the preset accelerator pedal opening-demand torque correspondence table, the base torque value corresponding to this opening is 50Nm. The current vehicle speed is 30km / h. According to the vehicle speed-torque correction coefficient table, the correction coefficient at this vehicle speed is 1.2. Then the driver's current demand torque value is 50Nm×1.2 = 60Nm.

[0050] S202: Control the first drive motor corresponding to the outer wheel of the rear axle of the vehicle to output the required torque value, and control the second drive motor corresponding to the inner wheel of the rear axle of the vehicle to output the negative current required torque value.

[0051] Figure 3 This is a schematic diagram of a vehicle turning left using the vehicle steering control method provided in this application. Figure 4 This is a schematic diagram of a vehicle turning right using the vehicle steering control method provided in this application.

[0052] Combination Figure 3 When applying the vehicle steering control method provided in this application, if the vehicle turns left, the first direction is left, and simultaneously the rear wheels of the vehicle are controlled to steer to the right at a preset angle in a second direction. At this time, the inner wheel of the rear axle is the left rear wheel, and the outer wheel of the rear axle is the right rear wheel. Combined with... Figure 4 If the vehicle turns right, the first direction is to the right. At the same time, the rear wheels of the vehicle are simultaneously controlled to turn to the left at a preset angle in the second direction. At this time, the inner wheel of the rear axle is the right rear wheel, and the outer wheel of the rear axle is the left rear wheel.

[0053] Based on the above, after obtaining the driver's current torque demand, the first drive motor on the outer rear axle outputs the demanded torque, while the second drive motor on the inner rear axle outputs a negative torque equal to the absolute value of the demanded torque. This torque difference drives the rear wheels to generate steering torque. It should be understood that this pair of equal and opposite forces act on both ends of the vehicle's rear axle "lever," forming a pure torque couple. This couple directly generates a torque that causes the vehicle to rotate around its vertical axis—the yaw moment. At this point, the yaw moment actively generated by the rear wheels is additional; it strongly superimposes on the natural yaw moment generated by the front wheel steering, thus assisting in vehicle steering and enabling small-radius steering.

[0054] Specifically, when the rear wheels need to turn right (second direction), the first drive motor of the right rear wheel (outer wheel) outputs positive torque to provide driving force, while the second drive motor of the left rear wheel (inner wheel) outputs negative torque to form braking force. The torque difference between the two wheels is transmitted to the rear wheel steering mechanism through the half-shafts, pushing the rear wheels to rotate around the kingpin to a preset turning angle. Conversely, when the rear wheels need to turn left, the drive motor of the left rear wheel outputs positive torque, and the drive motor of the right rear wheel outputs negative torque, achieving rear wheel steering in the second direction using the same principle.

[0055] It should be understood that when the above control method is applied, the output torque of the front axle drive motor is zero, and the vehicle steers solely by the yaw moment generated by the torque difference of the rear wheels.

[0056] Figure 5 This is a flowchart illustrating another embodiment of the vehicle steering control method provided in this application.

[0057] Combination Figure 5 In some specific embodiments, if a change in the current opening of the vehicle's accelerator pedal is detected, the torque change is determined based on the change in accelerator pedal opening, and the torque increase is allocated to the drive torque of the front axle drive motor, or the torque decrease is allocated to the energy recovery torque of the front axle drive motor, and the torque of the rear axle drive motor is maintained. Following this step, i.e., after step S103 above, the following steps are included:

[0058] S401: Obtain the vehicle's current speed and current control parameters; wherein, the current control parameters are generated by the driver's control behavior.

[0059] It should be understood that the vehicle's current speed can be obtained directly from the controller or from relevant sensors. The vehicle's current control parameters can include real-time input signals such as the driver's steering wheel angle, accelerator pedal opening, and brake pedal opening. These parameters directly reflect the driver's current driving intentions; for example, the speed and magnitude of changes in the steering wheel angle can reflect the urgency of the steering, and changes in the accelerator pedal opening can reflect the adjustment requirements for power output.

[0060] In this context, the accuracy and real-time nature of the current control parameters are crucial for subsequent steering control. Therefore, they can be acquired using high-precision sensors, and after signal filtering and validity verification, transmitted to the vehicle control unit for processing. In other application scenarios, these parameters can be directly acquired through relevant controllers. For example, the steering wheel angle signal can be directly acquired through the controller of the electronic power steering system (EPS), while the accelerator pedal and brake pedal opening signals can be read in real time through the engine control unit (ECU) or vehicle control unit (VCU). This acquisition method ensures rapid signal transmission and high accuracy, providing a reliable basis for subsequent precise control.

[0061] S402: Determine the current driving state of the vehicle based on the current vehicle speed and current control parameters, and exit the preset steering control mode if the current driving state does not conform to the preset steering state.

[0062] Based on the above, the current vehicle speed and current control parameters can reflect the real-time status of the vehicle. At this time, the current driving status of the vehicle can be determined according to the current vehicle speed and current control parameters, and it can be accurately determined whether the vehicle is still in a state that requires maintaining the preset steering control mode.

[0063] For example, when the vehicle completes a U-turn and the speed gradually increases, or when the driver straightens the steering wheel, the vehicle can determine that the current driving state has deviated from the preset steering state. At this time, it will automatically exit the preset steering control mode and return to the normal steering control logic. In this case, the vehicle can be steered by steering only the front wheels to ensure the stability and handling of the vehicle under normal driving conditions.

[0064] In some specific embodiments, the current control parameters of the vehicle include: the current steering wheel angle and the current brake pedal opening.

[0065] In this embodiment, the current control parameters include the current steering wheel angle and the current brake pedal opening. The current steering wheel angle can be obtained by real-time acquisition of signals from a steering wheel angle sensor. This angle signal, after processing by an angle sensor, accurately reflects the driver's steering input. The current brake pedal opening can be acquired by a displacement sensor mounted on the brake pedal. The displacement sensor transmits its signal to the controller, which further calculates the specific opening value based on a preset displacement-opening correspondence.

[0066] Based on the above, the current driving state of the vehicle is determined according to the current vehicle speed and current control parameters, and the step of exiting the preset steering control mode when the current driving state does not conform to the preset steering state, namely step S402, includes:

[0067] S502: If any of the following conditions are met: the current vehicle speed is greater than the preset vehicle speed, the current steering wheel angle is less than the preset steering angle, or the current brake pedal opening is greater than the preset opening, then it is determined that the current driving state does not meet the preset steering state, and the preset steering control mode is exited.

[0068] If any of the following conditions are met: the current vehicle speed is greater than the preset speed, the current steering wheel angle is greater than the preset angle, or the current brake pedal opening is greater than the preset opening, then the vehicle is determined to be in a high-speed driving, sharp turning, or emergency braking condition. In this case, the preset steering control mode is considered inapplicable. The preset speed, preset steering angle, and preset opening can be set according to actual needs. For example, the preset speed can be set to 11 kph, the preset steering angle can be set to 80% of the maximum steering wheel angle, and the preset opening can be set to 30% of the maximum brake pedal opening.

[0069] Based on the above, in some application scenarios, when a vehicle accelerates to over 11 km / h after completing a low-speed turn, the system will automatically recognize the high-speed driving state and exit the preset steering control mode to avoid the impact of rear-wheel steering on the vehicle's straight-line stability at high speeds. When the brake pedal opening exceeds 30%, it means that the driver may be decelerating. If the rear wheels are steering at this time, it may interfere with the vehicle's posture during braking. Therefore, the preset steering control mode is exited to ensure braking safety.

[0070] In other embodiments, the current fault level of the vehicle's drive motor can be obtained. If the current fault level is greater than a preset level, the preset steering control mode can be exited. In some application scenarios, the preset fault level can be set to level 5. For example, when the rear axle drive motor experiences faults such as overheating or overcurrent, and the fault level reaches level 5, the system determines that there may be a risk of abnormal fluctuations in the rear axle torque output. At this time, the preset steering control mode can be exited, and the driver can be alerted via the instrument panel fault indicator light to ensure driving safety.

[0071] Figure 6 This is a flowchart illustrating yet another embodiment of the vehicle steering control method provided in this application. (In conjunction with...) Figure 6 This method also includes:

[0072] S601: Obtain the current master cylinder pressure and current pushrod stroke of the vehicle, and determine the first current opening corresponding to the current master cylinder pressure and the second current opening corresponding to the current pushrod stroke.

[0073] In this embodiment, the current opening of the brake pedal is finally determined by the current master cylinder pressure and the current push rod stroke of the vehicle. This step first determines the corresponding first current opening and second current opening by using the current master cylinder pressure and the current push rod stroke respectively.

[0074] The master cylinder pressure is collected in real time by a pressure sensor installed on the brake master cylinder. This sensor converts the hydraulic pressure signal into an electrical signal and transmits it to the controller. The pushrod stroke is detected by a stroke sensor integrated into the brake pedal mechanism, directly reflecting the displacement of the pedal when it is depressed. It should be understood that when calculating the first current opening degree based on the master cylinder pressure, a pre-calibrated pressure-opening degree correspondence is required. This correspondence can be constructed based on experimental data of pressure and opening degree changes under different pedal forces. Similarly, the correspondence between the pushrod stroke and the second current opening degree can also be determined through a pre-calibrated pushrod stroke-opening degree correspondence.

[0075] S602: The smaller of the first current opening degree and the second current opening degree is taken as the current opening degree of the vehicle's brake pedal.

[0076] After obtaining the first current opening and the second current opening, this step further uses the smaller of the first current opening and the second current opening as the current opening of the vehicle's brake pedal. For example, if the current master cylinder pressure is 15 (Bar), the corresponding first current opening is 22.5, and the current pushrod travel is 90 (mm), the corresponding second current opening is 16. Then, the second current opening of 16 is used as the current opening of the brake pedal.

[0077] It should be understood that this configuration effectively avoids misjudgments of brake pedal opening caused by a single sensor malfunction, thus improving the reliability of brake pedal opening detection. For example, if the master cylinder pressure sensor outputs an abnormally high pressure value, resulting in a larger calculated first current opening, and the pushrod stroke sensor detects a smaller actual pushrod stroke, the calculated second current opening will also be smaller. In this case, the system will select the smaller second current opening as the final result, preventing incorrect judgments of brake pedal opening due to a master cylinder pressure sensor malfunction.

[0078] Figure 7 This is a flowchart illustrating another embodiment of the vehicle steering control method provided in this application.

[0079] Combination Figure 7 In some specific embodiments, the step of obtaining the current driving state of the vehicle and entering the preset steering control mode when the current driving state is a preset steering state, i.e., the above-mentioned step S101, includes:

[0080] S701: Obtain the vehicle's current speed, the current steering wheel angle, the driver's current torque demand, and the current fault level of the drive motor.

[0081] In this embodiment, the specific conditions for entering the preset steering control mode are further defined. This step obtains the vehicle's current speed, the current steering wheel angle, the driver's current torque requirement, and the current fault level of the drive motor.

[0082] Similarly, the current vehicle speed can be obtained through wheel speed sensors or a GPS positioning system, the current steering wheel angle is collected in real time by a steering angle sensor, and the driver's current torque demand is calculated by the controller after analyzing parameters such as accelerator pedal opening, brake pedal status, and current vehicle speed, reflecting the driver's expectation of vehicle power output. The current fault level of the drive motor is obtained through the fault diagnosis module of the motor controller, which can be obtained through key parameters such as motor temperature, current, and voltage. The fault level is usually classified based on the degree of impact on vehicle driving safety, and is divided into multiple levels from low to high, such as level 1 to level 10, with higher levels indicating more severe faults.

[0083] In some application scenarios, the driver's current torque demand can be obtained by looking up a table based on vehicle speed and accelerator pedal opening. For example, it can be obtained from the table below (the table only shows partial data), where x represents vehicle speed and y represents accelerator pedal opening.

[0084]

[0085] S702: When the current vehicle speed is within the preset speed range, the absolute value of the current steering angle is greater than the preset ratio of the maximum steering angle, the current required torque is less than the preset required torque, and the current fault level is lower than the preset fault level, the current driving state is determined to be the preset steering state, and the preset steering control mode is entered.

[0086] When the current vehicle speed is within a preset speed range, the absolute value of the current steering angle is greater than a preset proportion of the maximum steering angle, the current required torque is less than the preset required torque, and the current fault level is lower than the preset fault level, the vehicle is determined to be in a preset steering state that requires the activation of the preset steering control mode. The preset proportion can be 90%.

[0087] In some application scenarios, the preset vehicle speed range can be set to 0.5-10 kph, the preset required torque is set to 800 N·m, and the preset fault level is level 3. When the vehicle is traveling at a low speed of 5 kph, the steering wheel angle reaches 95% of the maximum angle, the driver's required torque is 300 N·m, and the drive motor fault level is level 2, the preset steering state conditions are met, and the vehicle enters the preset steering control mode. At this time, by coordinating the steering angles and torque distribution of the front and rear axles, the steering flexibility of the vehicle in low-speed, large-angle scenarios is improved.

[0088] Figure 8 This is a flowchart illustrating another embodiment of the vehicle steering control method provided in this application.

[0089] Combination Figure 8 In some specific embodiments, after the step of obtaining the current driving state of the vehicle and entering the preset steering control mode when the current driving state is a preset steering state, i.e. after the above step S101, the following is included:

[0090] S801: If the vehicle is in a preset slip condition, it will enter the preset chassis control mode.

[0091] The ability to pre-determine slippage conditions can be achieved by comprehensively analyzing parameters such as the wheel speed difference between the vehicle's wheels, lateral acceleration, and yaw rate. For example, when the difference between the drive wheel speed and the non-drive wheel speed exceeds a preset threshold, and the lateral acceleration is greater than a preset acceleration, the vehicle is determined to be slipping.

[0092] S802: In the preset chassis control mode, after controlling the vehicle's current yaw moment to reduce to zero and the current slip ratio to the target slip ratio, the preset steering control mode is entered.

[0093] In the preset chassis control mode, the system adjusts the vehicle's current yaw moment and slip ratio. Specifically, it adjusts the braking force distribution to each wheel and the torque output of the drive system to gradually reduce the current yaw moment to zero, thus suppressing excessive body yaw. Simultaneously, based on the road surface adhesion coefficient and current vehicle speed, it controls the slip ratio below the target slip ratio to restore effective adhesion between the wheels and the ground. The target slip ratio can be adaptively adjusted according to different road surface types (such as dry asphalt, wet / slippery surfaces, and icy / snowy surfaces) to adapt to varying driving environments.

[0094] It should be understood that once the vehicle's yaw moment is stable at zero and the slip ratio reaches the target slip ratio, it can be confirmed that the vehicle's attitude has returned to stability. At this point, the preset chassis control mode is exited and the preset steering control mode is re-entered to ensure the vehicle's steering performance and driving safety under complex road conditions.

[0095] A second aspect of this application provides an electronic device, including: a processor; and a memory for storing a computer program, wherein the computer program, when executed by the processor, implements the vehicle steering control method of any of the above embodiments. For a detailed description of the vehicle steering control method, please refer to the relevant content of the above embodiments, which will not be repeated here.

[0096] Figure 9 This is a schematic diagram of the structural framework of an embodiment of the electronic device 600 provided in this application.

[0097] Combination Figure 9 In some specific embodiments, the electronic device 600 includes a central processing unit (CPU) 601 and a read-only memory (ROM) 602. The CPU 601 is a processor, and the ROM 602 is a memory. The CPU 601 can perform various appropriate actions and processes, such as executing the methods described in the above embodiments, based on programs stored in the ROM 602 or programs loaded from storage portion 608 into random access memory (RAM) 603. The RAM 603 also stores various programs and data required for system operation. The CPU 601, ROM 602, and RAM 603 are interconnected via a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0098] The following components are connected to I / O interface 605: an input section 606 including a keyboard, mouse, etc.; an output section 607 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 608 including a hard disk, etc.; and a communication section 609 including a network interface card such as a LAN (Local Area Network) card, modem, etc. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to I / O interface 605 as needed. A removable medium 611, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 610 as needed so that computer programs read from it can be installed into storage section 608 as needed.

[0099] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program including a computer program for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 609, and / or installed from removable medium 611. When the computer program is executed by central processing unit (CPU) 601, it performs various functions defined in the system of this application.

[0100] A third aspect of this application provides a computer-readable storage medium 40, Figure 10 This is a schematic diagram of the structural framework of an embodiment of the computer-readable storage medium 40 provided in this application.

[0101] Combination Figure 10 The computer-readable storage medium 40 stores a computer program 41, which, when executed by a processor, implements the vehicle steering control method as described in any of the above embodiments.

[0102] It should be noted that the computer-readable medium 40 shown in the embodiments of this application can be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying a computer-readable computer program. The transmitted data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0103] In summary, the vehicle steering control method, electronic device, and storage medium provided in this application include: acquiring the current driving state of the vehicle, and entering a preset steering control mode when the current driving state is a preset steering state; in the preset steering control mode, controlling the front wheels of the vehicle to steer in a first direction with a target turning angle, and controlling the rear wheels of the vehicle to steer in a second direction with a preset turning angle; wherein the first direction and the second direction are opposite; if a change in the current opening of the accelerator pedal is detected, determining the torque change based on the change in the accelerator pedal opening, allocating the torque increase to the driving torque of the front axle drive motor, or allocating the torque decrease to the energy recovery torque of the front axle drive motor, and maintaining the torque of the rear axle drive motor; wherein the change in the accelerator pedal opening and the torque change have a preset correspondence; wherein the change in the accelerator pedal opening and the torque have a preset correspondence. Therefore, during the rear wheel anti-directional steering process, allocating the torque change to the front axle drive motor can achieve steering with a smaller steering radius while ensuring the lateral stability of the vehicle.

[0104] The above description is merely a preferred exemplary embodiment of this application and is not intended to limit the implementation of this application. Those skilled in the art can easily make corresponding modifications or alterations based on the main concept and spirit of this application. Therefore, the scope of protection of this application should be determined by the scope of protection claimed in the claims.

Claims

1. A vehicle steering control method characterized by, The method comprises: acquiring a current driving state of the vehicle, and entering a preset steering control mode when the current driving state is a preset steering state; in the preset steering control mode, controlling front wheels of the vehicle to steer in a first direction with a target steering angle, and controlling rear wheels of the vehicle to steer in a second direction with a preset steering angle; wherein the first direction is opposite to the second direction; if a change in a current opening degree of an accelerator pedal of the vehicle is detected, determining a torque change amount according to a change amount of the opening degree of the accelerator pedal, distributing a torque increase amount to a driving torque of a front axle drive motor, or distributing a torque decrease amount to an energy recovery torque of the front axle drive motor, and maintaining a torque of a rear axle drive motor; wherein the change amount of the opening degree of the accelerator pedal and the torque change amount have a preset corresponding relationship; the step of controlling the rear wheels of the vehicle to steer in the second direction with the preset steering angle comprises: acquiring a current demand torque value of a driver; controlling a first drive motor corresponding to an outer wheel pair of the rear axle of the vehicle to output the current demand torque value, and controlling a second drive motor corresponding to an inner wheel pair of the rear axle of the vehicle to output a negative current demand torque value.

2. The vehicle steering control method according to claim 1, characterized by, after the step of, if a change in a current opening degree of an accelerator pedal of the vehicle is detected, determining a torque change amount according to a change amount of the opening degree of the accelerator pedal, distributing a torque increase amount to a driving torque of a front axle drive motor, or distributing a torque decrease amount to an energy recovery torque of the front axle drive motor, and maintaining a torque of a rear axle drive motor, the method further comprises: acquiring a current vehicle speed and a current control parameter of the vehicle; wherein the current control parameter is generated by a driving behavior of the driver; determining a current driving state of the vehicle according to the current vehicle speed and the current control parameter, and exiting the preset steering control mode when the current driving state does not meet the preset steering state.

3. The vehicle steering control method according to claim 2, wherein the current control parameter comprises: a current steering angle of a steering wheel of the vehicle and a current opening degree of a brake pedal.

4. The vehicle steering control method according to claim 3, characterized by the step of determining a current driving state of the vehicle according to the current vehicle speed and the current control parameter, and exiting the preset steering control mode when the current driving state does not meet the preset steering state, comprises: if any one of the current vehicle speed of the vehicle being greater than a preset vehicle speed, the current steering angle of the steering wheel being less than a preset steering angle, and the current opening degree of the brake pedal being greater than a preset opening degree is met, it is determined that the current driving state does not meet the preset steering state, and the preset steering control mode is exited.

5. The vehicle steering control method according to claim 3, characterized by the method further comprises: acquiring a current master cylinder pressure and a current push rod stroke of the vehicle, and determining a first current opening degree corresponding to the current master cylinder pressure and a second current opening degree corresponding to the current push rod stroke; taking a smaller one of the first current opening degree and the second current opening degree as the current opening degree of the brake pedal of the vehicle.

6. The vehicle steering control method according to claim 1, wherein The step of acquiring a current driving state of the vehicle and entering a preset steering control mode when the current driving state is a preset steering state comprises: acquiring a current vehicle speed, a current steering wheel angle, a current demand torque of a driver, and a current fault level of a drive motor of the vehicle; when the current vehicle speed is within a preset vehicle speed range, an absolute value of the current steering wheel angle is greater than a preset proportion of a maximum steering wheel angle, the current demand torque is less than a preset demand torque, and the current fault level is lower than a preset fault level, determining that the current driving state is the preset steering state and entering the preset steering control mode.

7. The vehicle steering control method according to claim 1, characterized by, After the step of acquiring a current driving state of the vehicle and entering a preset steering control mode when the current driving state is a preset steering state, the method further comprises: if the vehicle is in a preset slipping working condition, entering a preset chassis control mode; after the current yaw moment of the vehicle is controlled to decrease to zero and the current slip ratio is controlled to decrease to a target slip ratio in the preset chassis control mode, entering the preset steering control mode.

8. An electronic device, comprising: comprise: a processor; a memory for storing a computer program, the computer program being executed by the processor to implement the vehicle steering control method of any one of claims 1-7.

9. A computer-readable storage medium, characterized in that, The storage medium has a computer program stored therein, and the computer program is executed by the processor to implement the vehicle steering control method of any one of claims 1-7.

Images