Rear wheel steering control method, device, vehicle, equipment and readable storage medium

Abstract

The rear wheel steering control method, device, vehicle, equipment and readable storage medium break the control logic that the rear wheel steering angle is reversed to the same direction steering by the front wheel in the process of accelerating into the curve under the conventional proportional control, avoid the vehicle driving state mutation caused by the rapid reversing of the rear wheel steering angle under the conventional proportional control, improve the control stability in the process of accelerating into the curve and reduce the driving risk; after the curve accelerating control strategy is activated, through the continuous identification and determination of the vehicle driving state, the curve accelerating control strategy is exited in time when the vehicle driving state meets the preset exit condition, and the conventional proportional control logic of the rear wheel steering is restored, without affecting the steering control characteristics in the conventional driving scene.

Description

Technical Field

[0001] This application relates to the field of vehicle control, specifically to a rear-wheel steering control method, device, vehicle, equipment, and readable storage medium. Background Technology

[0002] The new energy vehicle industry is developing rapidly, and vehicle handling agility and driving stability have become important research and development directions. Rear-wheel steering, due to its ability to effectively improve vehicle steering characteristics, is widely used in various new energy vehicles. This function controls the rear wheel steering angle to be opposite to the front wheel steering angle when the vehicle is traveling at low speeds, thereby reducing the vehicle's turning radius and improving maneuverability; at high speeds, it controls the rear wheel steering angle to be in the same direction as the front wheel steering angle, thereby enhancing vehicle stability.

[0003] In related technologies, the rear wheel steering angle is usually achieved by a proportional control method related to the front wheel steering angle. Existing rear wheel steering control methods are only designed for conventional driving scenarios and do not have a dedicated control strategy for the specific driving scenario of vehicle acceleration into a curve.

[0004] When a vehicle is accelerating into a curve, its speed continuously increases from a low speed range to a high speed range. Under normal proportional control, the rear wheel steering angle will rapidly change from an angle opposite to that of the front wheels to an angle in the same direction. This change will cause the vehicle's state to quickly switch from oversteering to understeering, resulting in a "pushing" phenomenon. This causes the vehicle's trajectory to deviate from the driver's expectations, and the driver will find it difficult to adjust the steering wheel in time to correct the situation. This can easily lead to driving risks such as the front of the vehicle scraping against the guardrail, seriously affecting the safety and handling stability of the vehicle during acceleration in a curve. Summary of the Invention

[0005] This application provides a rear-wheel steering control method, device, vehicle, equipment, and readable storage medium, which can solve the technical problem in the related art where, when a vehicle with rear-wheel steering accelerates into a curve, the rear wheel angle changes rapidly from the opposite direction to the same direction, causing the vehicle to understeer, deviate from the expected driving trajectory, and easily generate driving risks.

[0006] In a first aspect, embodiments of this application provide a rear-wheel steering control method, the rear-wheel steering control method comprising: When the vehicle is detected to be accelerating into a curve and it is determined that the front wheel steering angle and the rear wheel steering angle are in opposite directions, it is further determined whether the current driving speed has reached the critical speed condition for the vehicle to switch from rear wheel steering in opposite directions to steering in the same direction. If the condition is met, the cornering acceleration control strategy is activated to limit the requested angle of the rear wheel steering angle. After the cornering acceleration control strategy is activated, the system continuously identifies changes in the vehicle's driving status. When the vehicle's driving status meets the preset exit conditions, the cornering acceleration control strategy is exited.

[0007] In conjunction with the first aspect, in one implementation, identifying that the vehicle is accelerating into a curve includes: Collect data on the vehicle's steering wheel angle, accelerator pedal opening, and longitudinal acceleration; It is determined whether the steering wheel angle, accelerator pedal opening and longitudinal acceleration all meet their respective working condition judgment conditions. If they all meet the conditions, the vehicle is determined to be in the acceleration into a curve condition.

[0008] In conjunction with the first aspect, in one implementation, the acquisition of the vehicle's steering wheel angle, accelerator pedal opening, and longitudinal acceleration includes: The vehicle's onboard sensors and electronic control system collect various driving parameters in real time. The collected driving parameters are filtered and denoised to eliminate interference during the signal acquisition process; The processed driving parameters are transmitted to the vehicle's steering control unit for determining acceleration into corners.

[0009] In conjunction with the first aspect, in one implementation, determining that the steering angles of the front and rear wheels of the vehicle are in opposite directions includes: Collect the front wheel steering angle parameters and rear wheel steering angle parameters of the vehicle; Based on the front wheel steering angle parameters and the rear wheel steering angle parameters, determine whether the steering directions of the front and rear wheels are opposite. If they are opposite, it is determined to be a reverse steering relationship.

[0010] In conjunction with the first aspect, in one implementation, activating the cornering acceleration control strategy and limiting the requested angle of the rear wheel steering angle includes: Activate the cornering acceleration control strategy and deactivate the conventional proportional control mode for rear wheel steering; The cornering acceleration control strategy limits the adjustment range of the rear wheel angle so that the rear wheel angle can only be adjusted from the opposite angle to the front wheel to zero angle, and the rear wheel angle is prohibited from being adjusted to the same angle as the front wheel.

[0011] In conjunction with the first aspect, in one embodiment, adjusting the rear wheel steering angle only from an angle opposite to that of the front wheels to zero angle includes: During the activation of the cornering acceleration control strategy, the steering control unit sets the effective adjustment range of the rear wheel steering angle from the reverse angle to zero angle. The steering control unit monitors the rear wheel steering angle request signal in real time, and blocks steering angle request signals that exceed the effective adjustment range, only responding to effective request signals that adjust the angle in the opposite direction to zero.

[0012] In conjunction with the first aspect, in one implementation, the step of continuously identifying changes in the vehicle's driving state and exiting the cornering acceleration control strategy when the vehicle's driving state meets preset exit conditions includes: After the cornering acceleration control strategy is activated, real-time driving parameters such as steering wheel angle, accelerator pedal opening and longitudinal acceleration of the vehicle are continuously collected at a preset frequency. The real-time driving parameters are dynamically compared with the preset exit judgment conditions to identify in real time whether the vehicle's driving state is changing to a stable straight driving state. Determine whether any continuously collected real-time driving parameter meets the corresponding exit condition of the strategy. If any real-time driving parameter meets the exit condition, the vehicle is determined to meet the preset exit condition. Immediately terminate the cornering acceleration control strategy and restore the normal proportional control mode of rear wheel steering, so that the rear wheel angle is adjusted according to the vehicle's driving status and the normal control logic.

[0013] In conjunction with the first aspect, in one implementation, determining whether any continuously collected real-time driving parameter meets its corresponding strategy exit condition includes: Once any real-time driving parameter meets the corresponding strategy exit condition, the preset judgment time is maintained for continuous verification. If the real-time driving parameter remains within the range of the strategy exit condition during the determination period, the preset exit condition will be met, thus avoiding the strategy from exiting erroneously due to instantaneous fluctuations in the parameter.

[0014] In conjunction with the first aspect, in one embodiment, the rear wheel steering control method further includes the following steps: If the vehicle is not detected to be accelerating into a curve, or if it is determined that the front wheel steering angle and the rear wheel steering angle are not in opposite directions, or if the current vehicle speed does not meet the critical speed condition for the vehicle to switch from reverse steering of the rear wheels to steering in the same direction, then the conventional proportional control mode of the rear wheel steering is maintained, and the rear wheel steering angle is adjusted according to the front wheel steering angle ratio.

[0015] In conjunction with the first aspect, in one embodiment, the rear wheel steering control method is applicable to vehicles with rear wheel steering function and is compatible with the conventional proportional control logic of low-speed rear wheel reverse steering and high-speed rear wheel same-direction steering, and intervenes in the limited control of the rear wheel steering angle only when the activation conditions are met.

[0016] Secondly, embodiments of this application provide a rear-wheel steering control device, the rear-wheel steering control device comprising: The cornering acceleration control strategy activation module is used to further determine whether the current driving speed has reached the critical speed condition for the vehicle to switch from reverse steering of the rear wheels to same steering direction when it is detected that the vehicle is accelerating into a corner and the front wheel steering angle is in the opposite direction to the rear wheel steering angle. If the condition is met, the cornering acceleration control strategy is activated to limit the requested angle of the rear wheel steering angle. The cornering acceleration control strategy exit module is used to continuously identify changes in the vehicle's driving status after the cornering acceleration control strategy is activated, and exit the cornering acceleration control strategy when the vehicle's driving status meets the preset exit conditions.

[0017] In conjunction with the second aspect, in one embodiment, the cornering acceleration control strategy activation module is further used to collect the vehicle's steering wheel angle, accelerator pedal opening, and longitudinal acceleration; determine whether the steering wheel angle, accelerator pedal opening, and longitudinal acceleration all meet their respective working condition judgment conditions, and if all meet, determine that the vehicle is in the acceleration entering the corner working condition.

[0018] Thirdly, embodiments of this application provide a vehicle that includes the rear-wheel steering control device as described in the above embodiments.

[0019] Fourthly, embodiments of this application provide a rear-wheel steering control device, which includes a processor, a memory, and a rear-wheel steering control program stored in the memory and executable by the processor. When the rear-wheel steering control program is executed by the processor, it implements the steps of the rear-wheel steering control method as described in any of the above embodiments. Fifthly, embodiments of this application provide a computer-readable storage medium storing a rear-wheel steering control program, wherein when the rear-wheel steering control program is executed by a processor, it implements the steps of the rear-wheel steering control method as described in any of the above embodiments.

[0020] The beneficial effects of the technical solutions provided in this application include: By progressively determining the vehicle's acceleration into a curve, the opposing steering relationship between the front and rear wheels, and the vehicle's current speed, the cornering acceleration control strategy is activated only when all of these conditions are met. This strategy limits the requested angle of the rear wheel steering, breaking the conventional proportional control logic where the rear wheel steering angle changes from the opposite direction to the same direction as the front wheels during cornering acceleration. This avoids the sudden changes in vehicle driving state caused by rapid rear wheel steering angle changes under conventional proportional control, improving the vehicle's handling stability during cornering acceleration and reducing driving risks. After the cornering acceleration control strategy is activated, continuous identification and determination of the vehicle's driving state ensures that the strategy is promptly exited when the preset exit conditions are met, restoring the conventional proportional control logic for rear wheel steering without affecting steering characteristics in normal driving scenarios. Attached Figure Description

[0021] Figure 1 This is a schematic flowchart of an embodiment of the rear wheel steering control method of this application; Figure 2 This is a schematic diagram of the hardware structure of the rear wheel steering control device involved in the embodiments of this application. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0023] It's important to understand that with the rapid development of the new energy vehicle industry, vehicle handling agility and driving stability have become crucial research and development directions. Rear-wheel steering, due to its ability to effectively improve vehicle steering characteristics, is widely used in various new energy vehicles. This function controls the rear wheel steering angle to be opposite to the front wheel steering angle when the vehicle is traveling at low speeds, thereby reducing the vehicle's turning radius and improving maneuverability; at high speeds, it controls the rear wheel steering angle to be in the same direction as the front wheel steering angle, thereby enhancing vehicle stability.

[0024] In related technologies, the rear-wheel steering angle is typically achieved using a proportional control method related to the front-wheel steering angle. Specifically, the core of conventional proportional control for the rear-wheel steering angle in vehicles with rear-wheel steering is to use the front-wheel steering angle as the primary reference, and to achieve coordinated control of the rear-wheel steering angle and steering direction through a set proportional coefficient. Furthermore, this proportional control logic adapts to the vehicle's speed to meet the vehicle's handling requirements at different speeds. Existing rear-wheel steering control methods are only designed for conventional driving scenarios and do not have specific control strategies for the particular driving scenario of accelerating into a corner.

[0025] When a vehicle is accelerating into a curve, its speed continuously increases from a low speed range to a high speed range. Under normal proportional control, the rear wheel steering angle will rapidly change from an angle opposite to that of the front wheels to an angle in the same direction. This change will cause the vehicle's state to quickly switch from oversteering to understeering, resulting in a "pushing" phenomenon. This causes the vehicle's trajectory to deviate from the driver's expectations, and the driver will find it difficult to adjust the steering wheel in time to correct the situation. This can easily lead to driving risks such as the front of the vehicle scraping against the guardrail, seriously affecting the safety and handling stability of the vehicle during acceleration in a curve.

[0026] This application provides a rear-wheel steering control method, device, vehicle, equipment, and readable storage medium, which can solve the technical problem in the related art where, when a vehicle with rear-wheel steering accelerates into a curve, the rear wheel angle changes rapidly from the opposite direction to the same direction, causing the vehicle to understeer, deviate from the expected driving trajectory, and easily generate driving risks.

[0027] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0028] In a first aspect, embodiments of this application provide a rear-wheel steering control method.

[0029] In one embodiment, reference is made to Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the rear-wheel steering control method of this application. Figure 1 As shown, the rear-wheel steering control method includes: S100: When it is detected that the vehicle is accelerating into a curve and it is determined that the front wheel steering angle and the rear wheel steering angle are in opposite directions, it is further determined whether the current driving speed has reached the critical speed condition for the vehicle to switch from reverse steering of the rear wheels and front wheels to steering in the same direction. If the condition is met, the cornering acceleration control strategy is activated to limit the requested angle of the rear wheel steering angle. S200: After the cornering acceleration control strategy is activated, the system continuously identifies changes in the vehicle's driving status. When the vehicle's driving status meets the preset exit conditions, the system exits the cornering acceleration control strategy.

[0030] In this embodiment, by considering the vehicle's acceleration into a curve, the opposing steering relationship between the front and rear wheels, and whether the current vehicle speed reaches the critical speed condition for the vehicle to switch from opposing rear-wheel steering to unidirectional steering, the cornering acceleration control strategy is activated only when all of the above conditions are met. This limits the requested angle of the rear wheel steering, breaking the control logic of conventional proportional control where the rear wheel steering angle changes from opposing to unidirectional during acceleration into a curve. This achieves precise control over the adjustment range of the rear wheel steering angle, avoiding sudden changes in vehicle driving state caused by rapid rear wheel steering angle changes under conventional proportional control. This ensures the vehicle's trajectory matches the driver's expectations and avoids damage caused by vehicle movement. To address situations where sudden changes in driving conditions lead to delayed driver adjustments, this system improves vehicle handling stability and reduces driving risks during cornering acceleration. Furthermore, after the cornering acceleration control strategy is activated, continuous identification and judgment of the vehicle's driving status allows for timely exit of the strategy when preset exit conditions are met, restoring the conventional proportional control logic of rear-wheel steering. This control method only intervenes in the rear-wheel steering control process when activation conditions are met; under other driving conditions, the vehicle's original conventional proportional control logic for rear-wheel steering is maintained, ensuring compatibility with the vehicle's existing rear-wheel steering control system and not affecting the vehicle's steering characteristics in normal driving scenarios.

[0031] Furthermore, in one embodiment, S100 includes the following steps: S101: Collects vehicle steering wheel angle, accelerator pedal opening, and longitudinal acceleration; S102: Determine whether the steering wheel angle, accelerator pedal opening and longitudinal acceleration have all reached their respective working condition judgment conditions. If they have all reached the conditions, the vehicle is determined to be in the acceleration into a curve condition.

[0032] In this embodiment, three core driving parameters—steering wheel angle, accelerator pedal opening, and longitudinal acceleration—are collected during vehicle operation. These parameters are then matched and verified against specific operating condition criteria. The vehicle is determined to be accelerating into a curve only when all three parameters meet their respective criteria. By comprehensively collecting and collaboratively determining these multi-dimensional core driving parameters, accurate identification of the vehicle's acceleration into a curve is achieved. This avoids the misidentification issues that can arise from judging based on a single parameter, ensuring the accuracy of subsequent cornering acceleration control strategy triggering logic from the source of operating condition identification. It also prevents incorrect strategy intervention under non-acceleration into a curve condition. Furthermore, the collected parameters closely match the handling characteristics and vehicle motion state during acceleration into a curve, ensuring a high degree of consistency between the operating condition determination criteria and the actual driving conditions. This guarantees the authenticity and reliability of the acceleration into a curve determination results, laying the foundation for the accurate execution of subsequent steering control logic and ensuring the adaptability of the vehicle's steering control process to actual driving conditions.

[0033] Furthermore, in one embodiment, step S101 includes the following steps: S101-1: Real-time acquisition of various driving parameters through vehicle-mounted sensors and the vehicle's electronic control system; S101-2: Filter and denoise the collected driving parameters to eliminate interference during signal acquisition; S101-3: Transmits the processed driving parameters to the vehicle's steering control unit for determining acceleration into a curve.

[0034] In this embodiment, vehicle-mounted sensors and the vehicle's electronic control system collect real-time driving parameters such as steering wheel angle, accelerator pedal opening, and longitudinal acceleration. Filtering and noise reduction processes eliminate various interference signals during parameter acquisition, ensuring the authenticity and accuracy of the driving parameters. The processed, valid driving parameters are then transmitted to the vehicle's steering control unit, providing accurate and reliable parameters for determining acceleration into corners. This avoids misjudgments caused by interference in the collected parameters, ensuring that the parameters received by the steering control unit accurately reflect the vehicle's actual driving state. The parameter acquisition and processing stages guarantee the accurate execution of subsequent acceleration into corners determination logic, laying a reliable parameter foundation for the subsequent triggering and execution of the cornering acceleration control strategy.

[0035] Furthermore, in one embodiment, S100 includes the following steps: S103: Collect the front wheel steering angle parameters and rear wheel steering angle parameters of the vehicle; S104: Determine whether the steering directions of the front and rear wheels are opposite based on the front wheel steering angle parameters and the rear wheel steering angle parameters. If they are opposite, it is determined that they are in a reverse steering relationship.

[0036] In this embodiment, by collecting the front wheel and rear wheel steering angle parameters of the vehicle, the steering direction of the front and rear wheels is directly compared and judged based on the two types of steering angle parameters. Only when the steering directions of the front and rear wheels are determined to be opposite is the relationship between them determined to be reverse steering. By relying on the direct collection and direction comparison of the front and rear wheel steering angle parameters, the vehicle's steering relationship can be accurately determined. This provides an accurate basis for the activation determination of the subsequent cornering acceleration control strategy, avoids unnecessary intervention of the control strategy caused by misjudgment of the steering relationship, and ensures that the triggering logic of the steering control strategy is highly consistent with the actual steering state of the vehicle. By controlling the accuracy of the activation premise of the cornering acceleration control strategy from the steering state determination stage, reliable state support is provided for the accurate execution of subsequent steering control operations.

[0037] Furthermore, in one embodiment, S100 includes the following steps: S105: Activate the cornering acceleration control strategy and disable the conventional proportional control mode for rear wheel steering; S106: The cornering acceleration control strategy limits the adjustment range of the rear wheel angle so that the rear wheel angle can only be adjusted from the opposite angle to the front wheel to zero angle, and the rear wheel angle is prohibited from being adjusted to the same angle as the front wheel.

[0038] In this embodiment, by activating the cornering acceleration control strategy and simultaneously disabling the conventional proportional control method for rear-wheel steering, the adjustment range of the rear wheel angle is specifically limited based on this cornering acceleration control strategy. This ensures that the rear wheel angle can only be adjusted from the angle opposite to the front wheel to zero angle, while prohibiting the rear wheel angle from being adjusted to the same angle as the front wheel. This breaks the control logic of the rear wheel angle rotating from the opposite direction to the same direction during the vehicle's acceleration into a corner under conventional proportional control. It achieves strict control over the direction and range of rear wheel angle adjustment, making the rear wheel angle adjustment process conform to the working condition control requirements of the vehicle's acceleration into a corner. It achieves precise control of rear wheel steering from the core control link of angle adjustment, providing direct control support for the stability of the vehicle's steering state during acceleration into a corner, and avoiding the sudden change in vehicle steering state caused by rapid rear wheel angle reversal under conventional proportional control.

[0039] Furthermore, in one embodiment, S106 includes the following steps: S106-1: During the activation of the cornering acceleration control strategy, the steering control unit sets the effective adjustment range of the rear wheel angle from the reverse angle to zero angle. S106-2: The steering control unit monitors the rear wheel angle request signal in real time, and blocks the angle request signal that exceeds the effective adjustment range, and only responds to the effective request signal for adjustment of the reverse angle to zero angle.

[0040] In this embodiment, during the activation of the cornering acceleration control strategy, the vehicle steering control unit sets an effective adjustment range for the rear wheel steering angle from the reverse angle to zero angle. The steering control unit monitors the rear wheel steering angle request signals in real time, and filters out rear wheel steering angle request signals that exceed the effective adjustment range. It only responds to valid request signals that adjust the rear wheel steering angle from the reverse angle to zero angle. This achieves precise screening and control of the rear wheel steering angle request signals, ensuring that the adjustment action of the rear wheel steering angle is always limited to the preset effective adjustment range. This ensures that the limitation requirements for the rear wheel steering angle adjustment range are effectively implemented, avoiding excessive adjustment of the rear wheel steering angle caused by invalid steering angle request signals, and making the adjustment process of the rear wheel steering angle strictly conform to the control requirements of the cornering acceleration control strategy.

[0041] Furthermore, in one embodiment, step S200 includes the following steps: S201: After the cornering acceleration control strategy is activated, real-time driving parameters such as steering wheel angle, accelerator pedal opening and longitudinal acceleration of the vehicle are continuously collected at a preset frequency. S202: Dynamically compare the real-time driving parameters with the preset exit judgment conditions to identify in real time whether the vehicle's driving state is changing to a stable straight-line state. S203: Determine whether any continuously collected real-time driving parameter meets the corresponding exit condition of the strategy. If any real-time driving parameter meets the exit condition, the vehicle is determined to meet the preset exit condition. S204: Immediately terminate the execution of the cornering acceleration control strategy, restore the normal proportional control mode of rear wheel steering, and adjust the rear wheel angle according to the vehicle's driving status and the normal control logic.

[0042] In this embodiment, after the cornering acceleration control strategy is activated, real-time driving parameters such as the vehicle's steering wheel angle, accelerator pedal opening, and longitudinal acceleration are continuously collected at a preset frequency. These real-time driving parameters are dynamically compared with preset exit judgment conditions to identify in real time whether the vehicle's driving state is changing towards a stable straight-line state. Relying on continuous parameter collection and dynamic condition comparison, real-time and continuous vehicle driving state data is provided for the exit judgment of the cornering acceleration control strategy. This ensures that the exit judgment process is synchronized with the dynamic changes in the vehicle's driving state, and that the process of the vehicle's driving state changing towards a stable straight-line state can be captured in a timely manner. This avoids delays in strategy exit judgment caused by discontinuous parameter collection or lagging comparison, and ensures that the judgment criteria for strategy exit always match the real-time driving state of the vehicle. By determining whether any continuously collected real-time driving parameter of the vehicle meets the corresponding strategy exit condition, if any real-time driving parameter meets the condition, the vehicle is deemed to meet the preset exit condition. Once the preset exit condition is met, the execution of the cornering acceleration control strategy is immediately terminated, and the conventional proportional control mode of the rear wheel steering is restored. This allows the rear wheel angle to be adaptively adjusted according to the actual driving state of the vehicle and the conventional control logic of the rear wheel steering. This avoids the cornering acceleration control strategy from continuously intervening when the vehicle is not under control, ensuring the rigor of the strategy exit determination and the timeliness of the exit operation. At the same time, it allows the rear wheel steering control to quickly return to the conventional control system, ensuring that the steering characteristics of the vehicle in non-acceleration cornering conditions are consistent with the original conventional proportional control logic, thus meeting the rear wheel steering control requirements of the vehicle under different driving conditions.

[0043] Furthermore, in one embodiment, step S203 includes the following steps: S203-1: When any real-time driving parameter reaches the corresponding strategy exit condition, continue to verify for a preset judgment time. S203-2: If all parameters remain within the policy exit condition range during the determination period, the final determination will satisfy the preset exit condition, thus avoiding policy erroneous exit due to instantaneous parameter fluctuations.

[0044] In this embodiment, after each real-time driving parameter reaches its corresponding strategy exit condition, the state of the real-time driving parameter is continuously verified for a preset judgment period. Only when the real-time driving parameter is continuously maintained within the corresponding strategy exit condition range within the judgment period is the vehicle finally determined to meet the preset exit condition. By continuously verifying and judging the parameter state, the situation of erroneous exit of the cornering acceleration control strategy caused by instantaneous fluctuations in driving parameters is avoided. This ensures that the judgment result of strategy exit matches the change in the actual driving state of the vehicle, prevents the strategy from exiting prematurely due to changes in the actual driving state of the vehicle, and ensures that the execution cycle of the cornering acceleration control strategy is highly adapted to the actual control requirements of the vehicle accelerating into the corner, making the judgment of strategy exit rigorous and reliable.

[0045] Furthermore, in one embodiment, the following steps are included after or before S200: S300: If the vehicle is not detected to be accelerating into a curve, or if it is determined that the front wheel steering angle and the rear wheel steering angle are not in opposite directions, or if the current driving speed does not meet the critical speed condition for the vehicle to switch from reverse steering of the rear wheels to steering in the same direction, then the conventional proportional control mode of the rear wheel steering is maintained, and the rear wheel steering angle is adjusted according to the front wheel steering angle ratio.

[0046] In this embodiment, for any situation where the vehicle is not detected to be accelerating into a curve, the front wheel angle and the rear wheel angle are determined to be in a non-reverse steering relationship, or the current vehicle speed does not meet the preset speed conditions, the conventional proportional control mode of the rear wheel steering is maintained. The rear wheel angle is adjusted according to the proportion of the front wheel angle, so that the cornering acceleration control strategy only intervenes in the control process of the vehicle's rear wheel steering when all activation judgment conditions are met. In other driving situations, the original conventional proportional control logic of the vehicle's rear wheel steering is maintained, ensuring that the intervention of the cornering acceleration control strategy has clear targeting and avoiding unnecessary intervention of the strategy in driving conditions where there is no need for acceleration into a curve. This ensures that the handling characteristics of the rear wheel steering of the vehicle in normal driving scenarios are consistent with the original control logic, and meets the rear wheel steering control requirements of the vehicle under different driving conditions.

[0047] Furthermore, in one embodiment, the rear wheel steering control method is applicable to vehicles with rear wheel steering function and is compatible with the conventional proportional control logic of low-speed rear wheel reverse steering and high-speed rear wheel same-direction steering, and intervenes in the limited control of rear wheel steering angle only when the activation condition is met.

[0048] In this embodiment, the rear-wheel steering control method is adapted to vehicles equipped with rear-wheel steering function and is consistent with the conventional proportional control logic of rear-wheel steering, which states that the rear wheels steer in the opposite direction to the front wheels when the vehicle is traveling at low speeds and in the same direction as the front wheels when the vehicle is traveling at high speeds. This method only implements limited control on the rear wheel angle of the vehicle when all activation conditions of the cornering acceleration control strategy are met. In all other driving conditions, it does not intervene in the conventional control process of rear-wheel steering, ensuring that the control intervention action of this method does not conflict with the original conventional control logic of the vehicle's rear-wheel steering and does not change the rear-wheel steering handling characteristics of the vehicle in normal driving scenarios. The limited control of the rear wheel angle for cornering acceleration scenarios is only used as a supplementary control logic to the conventional proportional control of the vehicle's rear-wheel steering, and the overall system adapts to the management and control requirements of the vehicle's original rear-wheel steering control system.

[0049] On another front, this application provides a rear-wheel steering control method, and the complete technical solution is summarized and described below: It is important to understand that when a vehicle accelerates into a curve, the speed continuously increases from a low speed range to a high speed range. Under normal proportional control, the rear wheel steering angle will turn from the opposite angle to the same angle as the front wheel, causing the vehicle's state to quickly switch from oversteering to understeering, resulting in a "pushing" phenomenon. This phenomenon will cause the vehicle's trajectory to deviate from the driver's expected trajectory, and the driver will find it difficult to adjust the steering wheel in time to correct it, which may lead to the risk of the front of the vehicle scraping against the guardrail.

[0050] Therefore, this application embodiment designs a rear-wheel steering control method for vehicles with rear-wheel steering in acceleration-in-corner scenarios. The method consists of four core steps: acceleration-in-corner condition identification, front-rear wheel steering relationship determination, cornering acceleration control strategy activation and angle control, and cornering acceleration control strategy deactivation. The determination conditions and control actions for each step are as follows: Step 1: Identify the situation where the vehicle enters the curve with high acceleration. A vehicle is considered to be accelerating into a corner when all three of the following quantitative criteria are met simultaneously; none of the three criteria can be missing: ① If the absolute value of the vehicle's steering wheel angle AgEPS is greater than 90°, the vehicle is determined to be in a turning condition. ② The accelerator pedal opening P of the vehicle is greater than 40%; ③ The vehicle's longitudinal acceleration is greater than 0.3g.

[0051] Step 2: Determine whether the rear wheels and front wheels are in opposite steering directions. By calculating formula A gF *A gR The condition is determined when A is less than 0. gF For the front wheel steering angle, A gRThe product of the rear wheel angles is less than 0. If the product of the front and rear wheel angles is less than 0, it is determined that the rear wheels are turning in the opposite direction to the front wheels, and the vehicle is in an oversteer state.

[0052] Step 3: Activate cornering acceleration control strategy and control rear wheel steering angle Strategy activation determination: If the vehicle meets the above conditions of acceleration into corner and front and rear wheels turning in opposite directions, and the vehicle speed is higher than the low speed critical speed, for example, the low speed critical speed is 5 kph (this speed node is the key node when the vehicle is about to switch from rear wheel counter-steering to rear wheel same-direction steering), then the cornering acceleration control function / strategy is activated. Rear wheel steering angle control action: After the strategy is activated, the vehicle no longer uses the conventional proportional angle control method for rear wheel steering. At the same time, the requested angle of rear wheel steering is strictly limited, prohibiting the rear wheel steering angle from being in the same direction as the front wheel steering angle. Only the rear wheel steering angle is allowed to gradually change from the current opposite angle to 0°, so as to ensure that the vehicle's driving trajectory meets the driver's expectations and ensures the smoothness of acceleration driving in curves.

[0053] Step 4: Exit the cornering acceleration control strategy When a vehicle meets any of the following three quantitative judgment conditions, it is determined that the vehicle gradually returns to a stable straight-line state. At this time, the cornering acceleration control strategy is immediately discontinued, and the vehicle resumes the conventional proportional control mode of rear wheel steering. The three discontinuation conditions are as follows: ① The absolute value of the vehicle's steering wheel angle is less than 15°; ② The vehicle's longitudinal acceleration is less than 0.1g; ③ The vehicle's accelerator pedal opening P is less than 15%.

[0054] In summary, a rear-wheel steering handling strategy for vehicles with rear-wheel steering during cornering acceleration is proposed, filling a control gap in this driving scenario. It effectively solves the problem of excessive understeer caused by the rear wheel angle suddenly changing from the opposite direction to the same direction during cornering acceleration, leaving the driver insufficient time to adjust the steering wheel. This fundamentally avoids dangerous situations such as the vehicle's front end scraping against the guardrail in this scenario. By precisely limiting the rear wheel angle, it ensures that the vehicle's trajectory during acceleration into the corner matches the driver's expectations, improving driving safety and comfort in this scenario.

[0055] Secondly, this application embodiment also provides a rear-wheel steering control device, which includes: a cornering acceleration control strategy activation module, which is used to further determine whether the current driving speed has reached the critical speed condition for the vehicle to switch from rear-wheel and front-wheel reverse steering to same-direction steering when the vehicle is detected to be accelerating into a corner and the front wheel steering angle and rear wheel steering angle are determined to be in opposite directions; if the condition is met, the cornering acceleration control strategy is activated to limit the requested angle of the rear wheel steering angle; and a cornering acceleration control strategy exit module, which is used to continuously identify changes in the vehicle's driving state after the cornering acceleration control strategy is activated, and exit the cornering acceleration control strategy when the vehicle's driving state meets the preset exit conditions.

[0056] In this embodiment, the provided rear-wheel steering control device forms a collaborative control architecture with a cornering acceleration control strategy activation module and a cornering acceleration control strategy deactivation module. The cornering acceleration control strategy activation module comprehensively determines the vehicle's acceleration into a corner, the front and rear wheel steering relationship, and the current vehicle speed preset conditions. It activates the cornering acceleration control strategy only when all conditions are met and limits the requested rear wheel steering angle, achieving precise intervention in rear-wheel steering control under special cornering acceleration conditions. The cornering acceleration control strategy deactivation module continuously captures the dynamic changes in the vehicle's driving state after the cornering acceleration control strategy is activated. When the vehicle's driving state matches the preset deactivation conditions, it promptly executes the strategy deactivation operation, achieving full-process dynamic control of the rear-wheel steering strategy. This allows the device to specifically target the vehicle... This device provides dedicated steering control for acceleration into corners, avoiding the sudden changes in vehicle driving state caused by conventional rear-wheel steering control logic in this situation. It ensures that the rear-wheel steering control actions are adapted to the actual driving needs of the vehicle accelerating into a corner, while guaranteeing that the device intervenes only under specific conditions and does not interfere with the vehicle's original rear-wheel steering control logic in other driving scenarios. It is highly compatible with the conventional control system of vehicles with rear-wheel steering. Through modular functional division, it achieves precise and efficient control of rear-wheel steering during acceleration into corners, ensuring stable handling during cornering acceleration and aligning the vehicle's trajectory with the driver's expectations, reducing driving risks in this condition. Furthermore, the modular structural design makes the device's control logic clear and its execution precise, ensuring that all steering control operations are implemented efficiently.

[0057] The functions of each module in the aforementioned rear wheel steering control device correspond to the steps in the aforementioned rear wheel steering control method embodiment, and their functions and implementation processes will not be described in detail here.

[0058] Thirdly, embodiments of this application provide a vehicle that includes the rear-wheel steering control device as described in the above embodiments.

[0059] Fourthly, embodiments of this application provide a rear-wheel steering control device, which can be a device with data processing capabilities such as a personal computer (PC), a laptop computer, or a server.

[0060] Reference Figure 2 , Figure 2 This is a schematic diagram of the hardware structure of the rear-wheel steering control device involved in the embodiments of this application. In the embodiments of this application, the rear-wheel steering control device may include a processor, a memory, a communication interface, and a communication bus.

[0061] The communication bus can be of any type and is used to interconnect the processor, memory, and communication interface.

[0062] The communication interface includes input / output (I / O) interfaces, physical interfaces, and logical interfaces used to interconnect components within the rear-wheel steering control device, as well as interfaces used to interconnect the rear-wheel steering control device with other devices (such as other computing devices or user equipment). Physical interfaces can be Ethernet interfaces, fiber optic interfaces, ATM interfaces, etc.; user equipment can be displays, keyboards, etc.

[0063] Memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0064] The processor can be a general-purpose processor, which can call the rear-wheel steering control program stored in the memory and execute the rear-wheel steering control method provided in the embodiments of this application. For example, the general-purpose processor can be a central processing unit (CPU). The method executed when the rear-wheel steering control program is called can be referred to in the various embodiments of the rear-wheel steering control method of this application, and will not be repeated here.

[0065] Those skilled in the art will understand that Figure 2 The hardware structure shown does not constitute a limitation of this application and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0066] Fifthly, embodiments of this application also provide a readable storage medium.

[0067] The present application has a readable storage medium storing a rear wheel steering control program, wherein when the rear wheel steering control program is executed by a processor, it implements the steps of the rear wheel steering control method as described above.

[0068] The method implemented when the rear wheel steering control program is executed can be referred to in various embodiments of the rear wheel steering control method of this application, and will not be repeated here.

[0069] It should be noted that the sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0070] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.

[0071] In the description of the embodiments of this application, terms such as "exemplary," "for example," or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary," "for example," or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a concrete manner.

[0072] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more.

[0073] In some processes described in the embodiments of this application, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of this application, or they may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0074] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of this application.

[0075] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A rear-wheel steering control method, characterized in that, The rear wheel steering control method includes: When the vehicle is detected to be accelerating into a curve and it is determined that the front wheel steering angle and the rear wheel steering angle are in opposite directions, it is further determined whether the current driving speed has reached the critical speed condition for the vehicle to switch from rear wheel steering in opposite directions to steering in the same direction. If the condition is met, the cornering acceleration control strategy is activated to limit the requested angle of the rear wheel steering angle. After the cornering acceleration control strategy is activated, the system continuously identifies changes in the vehicle's driving status. When the vehicle's driving status meets the preset exit conditions, the cornering acceleration control strategy is exited.

2. The rear-wheel steering control method as described in claim 1, characterized in that, The identification of a vehicle accelerating into a curve includes: Collect data on the vehicle's steering wheel angle, accelerator pedal opening, and longitudinal acceleration; It is determined whether the steering wheel angle, accelerator pedal opening and longitudinal acceleration all meet their respective working condition judgment conditions. If they all meet the conditions, the vehicle is determined to be in the acceleration into a curve condition.

3. The rear-wheel steering control method as described in claim 2, characterized in that, The data collected include the vehicle's steering wheel angle, accelerator pedal opening, and longitudinal acceleration, including: The vehicle's onboard sensors and electronic control system collect various driving parameters in real time. The collected driving parameters are filtered and denoised to eliminate interference during the signal acquisition process; The processed driving parameters are transmitted to the vehicle's steering control unit for determining acceleration into corners.

4. The rear-wheel steering control method as described in claim 1, characterized in that, The determination that the steering angles of the front and rear wheels of a vehicle are in opposite directions includes: Collect the front wheel steering angle parameters and rear wheel steering angle parameters of the vehicle; Based on the front wheel steering angle parameters and the rear wheel steering angle parameters, determine whether the steering directions of the front and rear wheels are opposite. If they are opposite, it is determined to be a reverse steering relationship.

5. The rear-wheel steering control method as described in claim 1, characterized in that, The activation of the cornering acceleration control strategy and the limitation of the requested angle of the rear wheel steering angle include: Activate the cornering acceleration control strategy and deactivate the conventional proportional control mode for rear wheel steering; The cornering acceleration control strategy limits the adjustment range of the rear wheel angle so that the rear wheel angle can only be adjusted from the opposite angle to the front wheel to zero angle, and the rear wheel angle is prohibited from being adjusted to the same angle as the front wheel.

6. The rear-wheel steering control method as described in claim 5, characterized in that, The method of adjusting the rear wheel steering angle only from an angle opposite to that of the front wheel to zero includes: During the activation of the cornering acceleration control strategy, the steering control unit sets the effective adjustment range of the rear wheel steering angle from the reverse angle to zero angle. The steering control unit monitors the rear wheel steering angle request signal in real time, and blocks steering angle request signals that exceed the effective adjustment range, only responding to effective request signals that adjust the angle in the opposite direction to zero.

7. The rear-wheel steering control method as described in claim 1, characterized in that, The continuous identification of changes in the vehicle's driving state, and the exit of the cornering acceleration control strategy when the vehicle's driving state meets preset exit conditions, includes: After the cornering acceleration control strategy is activated, real-time driving parameters such as steering wheel angle, accelerator pedal opening and longitudinal acceleration of the vehicle are continuously collected at a preset frequency. The real-time driving parameters are dynamically compared with the preset exit judgment conditions to identify in real time whether the vehicle's driving state is changing to a stable straight driving state. Determine whether any continuously collected real-time driving parameter meets the corresponding exit condition of the strategy. If any real-time driving parameter meets the exit condition, the vehicle is determined to meet the preset exit condition. Immediately terminate the cornering acceleration control strategy and restore the normal proportional control mode of rear wheel steering, so that the rear wheel angle is adjusted according to the vehicle's driving status and the normal control logic.

8. The rear-wheel steering control method as described in claim 7, characterized in that, The determination of whether any continuously collected real-time driving parameter meets its corresponding strategy exit condition includes: When any real-time driving parameter reaches the corresponding strategy exit condition, the preset judgment time is maintained for continuous verification. If the real-time driving parameter remains within the range of the strategy exit condition during the determination period, the preset exit condition is finally met to avoid the strategy from exiting erroneously due to instantaneous fluctuations in the parameter.

9. The rear-wheel steering control method as described in claim 1, characterized in that, The rear wheel steering control method further includes the following steps: If the vehicle is not detected to be accelerating into a curve, or if it is determined that the front wheel steering angle and the rear wheel steering angle are not in opposite directions, or if the current vehicle speed does not meet the critical speed condition for the vehicle to switch from reverse steering of the rear wheels to steering in the same direction, then the conventional proportional control mode of the rear wheel steering is maintained, and the rear wheel steering angle is adjusted according to the front wheel steering angle ratio.

10. The rear-wheel steering control method as described in claim 1, characterized in that, The rear-wheel steering control method is applicable to vehicles with rear-wheel steering function and is compatible with the conventional proportional control logic of low-speed rear-wheel reverse steering and high-speed rear-wheel same-direction steering. It only intervenes in the limited control of the rear wheel steering angle when the activation conditions are met.

11. A rear-wheel steering control device, characterized in that, The rear wheel steering control device includes: The cornering acceleration control strategy activation module is used to further determine whether the current driving speed has reached the critical speed condition for the vehicle to switch from reverse steering of the rear wheels to same steering direction when it is detected that the vehicle is accelerating into a corner and the front wheel steering angle is in the opposite direction to the rear wheel steering angle. If the condition is met, the cornering acceleration control strategy is activated to limit the requested angle of the rear wheel steering angle. The cornering acceleration control strategy exit module is used to continuously identify changes in the vehicle's driving status after the cornering acceleration control strategy is activated, and exit the cornering acceleration control strategy when the vehicle's driving status meets the preset exit conditions.

12. The rear wheel steering control device as described in claim 11, characterized in that, The cornering acceleration control strategy activation module is also used to collect the vehicle's steering wheel angle, accelerator pedal opening, and longitudinal acceleration; and to determine whether the steering wheel angle, accelerator pedal opening, and longitudinal acceleration all meet their respective working condition judgment conditions. If all conditions are met, the vehicle is determined to be in the acceleration entering the corner condition.

13. A vehicle, characterized in that, It includes the rear wheel steering control device as described in claim 12.

14. A rear-wheel steering control device, characterized in that, The rear wheel steering control device includes a processor, a memory, and a rear wheel steering control program stored in the memory and executable by the processor, wherein when the rear wheel steering control program is executed by the processor, it implements the steps of the rear wheel steering control method as described in any one of claims 1 to 10.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a rear-wheel steering control program, wherein when the rear-wheel steering control program is executed by a processor, it implements the steps of the rear-wheel steering control method as described in any one of claims 1 to 10.

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