Vehicle brake control method and related device

Abstract

The application provides a vehicle braking control method and related equipment, relates to the technical field of vehicle control, and the method comprises the following steps: acquiring the vehicle speed of a vehicle and / or the road surface adhesion coefficient of a road on which the vehicle travels, and determining a vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient; acquiring the steering wheel turning angle and the steering angle speed of the vehicle, and determining a steering intention risk coefficient based on the steering wheel turning angle and the steering angle speed; determining a comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient; if the comprehensive risk coefficient meets a preset risk benchmark and the vehicle is in a preset braking working condition, a first braking strategy or a second braking strategy is used to execute vehicle braking, the first braking strategy comprises the following steps: executing an electro-hydraulic torque conversion operation, determining a target electric feedback torque and a target hydraulic braking torque, and executing vehicle braking based on the target electric feedback torque and the target hydraulic braking torque. The application can improve the stability and safety of vehicle driving.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to a vehicle braking control method and related equipment. Background Technology

[0002] Due to cost considerations, some new energy vehicles are either front-wheel drive or rear-wheel drive. For front-wheel drive vehicles, the front wheels can be braked via electro-regenerative braking, while the rear wheels use hydraulic braking. For rear-wheel drive vehicles, the rear wheels can be braked via electro-regenerative braking, while the front wheels use hydraulic braking. In actual braking control strategies, electro-regenerative braking generally takes priority. However, electro-regenerative braking can cause the combined tire force on that axle to approach the friction circle limit, resulting in low lateral force reserve. When the driver performs a steering maneuver, this axle, due to insufficient lateral stiffness, cannot effectively support the vehicle's yaw response. Especially in emergency or rapid steering conditions, this can easily induce understeer or fishtailing, not only reducing handling stability but also potentially threatening driving safety. Summary of the Invention

[0003] In view of this, this application provides a vehicle braking control method and related equipment, which can solve the problem of poor handling stability of existing vehicles under braking conditions, and can improve the stability and safety of vehicle driving.

[0004] In a first aspect, embodiments of this application provide a vehicle braking control method, comprising: acquiring the vehicle speed and / or the road surface adhesion coefficient of the road on which the vehicle travels, and determining a vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient; acquiring the steering wheel angle and steering angular velocity of the vehicle, and determining a steering intention risk coefficient based on the steering wheel angle and steering angular velocity; determining a comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient; and if the comprehensive risk coefficient meets a preset risk benchmark and the vehicle is in a preset braking condition, performing vehicle braking using a first braking strategy or a second braking strategy; wherein the first braking strategy includes: performing an electro-hydraulic torque conversion operation, determining a target electro-regenerative torque and a target hydraulic braking torque, and performing vehicle braking based on the target electro-regenerative torque and the target hydraulic braking torque, the electro-hydraulic torque conversion operation including gradually reducing the electro-regenerative torque according to a preset rule. The first braking strategy involves gradually increasing the hydraulic braking torque while maintaining the sum of the electro-regenerative torque and the hydraulic braking torque equal to the total braking torque. The total braking torque is determined based on the target braking deceleration corresponding to the preset braking condition. The preset rule includes determining the target hydraulic braking torque based on the total braking torque and a preset function. The target electro-regenerative torque is determined based on the target hydraulic braking torque and the total braking torque. The preset function includes a time variable and a calibration constant corresponding to the comprehensive risk coefficient. The second braking strategy includes: obtaining the type of braking system in effect for the vehicle; determining a braking force distribution strategy based on the braking system type; distributing the total braking force based on the braking force distribution strategy; and performing vehicle braking based on the braking force distribution result. The total braking force is determined based on the target braking deceleration corresponding to the preset braking condition. The braking force distribution strategy includes adjusting the braking force distribution ratio between the front axle and the rear axle based on the comprehensive risk coefficient.

[0005] Compared with related technologies, the embodiments of this application have at least the following advantages: A comprehensive risk coefficient is established based on multiple factors, including steering wheel angle, steering angular velocity, vehicle speed, and road surface adhesion coefficient, to comprehensively reflect the vehicle's steering risk. This comprehensive risk coefficient is used to determine whether to perform electro-hydraulic torque conversion, upgrading it from passively responding to braking requests to actively predicting steering instability trends. This improves vehicle driving safety. Furthermore, by performing electro-hydraulic torque conversion under high-risk steering conditions, the single-axle electro-regenerative torque distribution is switched to front-rear hydraulic braking torque distribution, avoiding the impact of single-axle electro-regenerative braking on vehicle yaw stability under high-risk steering conditions. This improves vehicle lateral stability and reduces the possibility of understeer or fishtailing. Moreover, suppressing understeer or fishtailing through electro-hydraulic torque conversion makes the vehicle stability control system less likely to activate, reducing the frequency of intervention and thus reducing [the risk of understeer / fishtailing]. The cumulative activation time of the vehicle stability control system throughout its entire lifecycle reduces the occurrence of conditions with large yaw rate overshoot, which helps suppress yaw rate overshoot. Another approach is to determine whether to adjust the front-to-rear axle braking force distribution ratio based on a comprehensive risk factor, improving lateral stability and reducing the likelihood of understeer or fishtailing. This approach is applicable to different braking system types, allowing for different braking force distribution adjustment strategies, resulting in higher yaw control precision and further ensuring vehicle stability and safety. Dynamically adjusting the front-to-rear axle braking force distribution ratio also suppresses understeer or fishtailing, making the vehicle stability control system less prone to activation and reducing its intervention frequency. This reduces the cumulative activation time of the vehicle stability control system throughout its lifecycle, minimizing conditions with large yaw rate overshoot and thus helping to suppress yaw rate overshoot.

[0006] In some possible embodiments, determining the vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient includes: querying a first mapping table based on the vehicle speed range and the road surface adhesion coefficient range to which the vehicle speed belongs, to determine the vehicle driving risk coefficient. The first mapping table includes a mapping relationship between the combination of the vehicle speed range and the road surface adhesion coefficient range and the vehicle driving risk coefficient. Determining the steering intention risk coefficient based on the steering wheel angle and steering angular velocity includes: querying a second mapping table based on the steering wheel angle range and the steering angular velocity range to which the steering wheel angle belongs, to determine the steering intention risk coefficient. The second mapping table includes a mapping relationship between the combination of the steering wheel angle range and the steering angular velocity range and the steering intention risk coefficient.

[0007] Compared with related technologies, the embodiments of this application have at least the following advantages: by querying the corresponding mapping table based on the vehicle speed range and the road surface adhesion coefficient range, the vehicle driving risk coefficient is determined; by querying the corresponding mapping table based on the steering wheel angle range and the steering angular velocity range, the steering intention risk coefficient is determined. This achieves the determination of the vehicle driving risk coefficient and the steering intention risk coefficient without performing complex calculations, with low computing power and fast response speed. Furthermore, the risk coefficient is calibrated based on the interval discrete method, which not only adapts to various working conditions but also suppresses the risk coefficient jitter caused by small disturbances.

[0008] In some possible embodiments, determining the comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient includes: inputting the vehicle driving risk coefficient and the steering intention risk coefficient into a preset nonlinear function to determine the comprehensive risk coefficient, wherein the preset nonlinear function has the characteristic that the output changes abruptly after the input increases to a threshold.

[0009] Compared with related technologies, the embodiments of this application have at least the following advantages: by configuring the nonlinear function to have the characteristic that the output changes abruptly after the input increases to a threshold, it is possible to simulate critical instability and sudden change when determining the comprehensive risk coefficient based on the preset nonlinear function, thereby avoiding the conservatism of risk estimation caused by linear superposition and improving the accuracy of risk estimation.

[0010] In some possible embodiments, determining the target hydraulic braking torque includes: determining the target hydraulic braking torque based on the following formula: T_hyd(t) = T_total × (1 - ), where T_hyd(t) is the target hydraulic braking torque, T_total is the total braking torque, and t is the time variable. The calibration constant is defined as such, and different calibration constants correspond to different interval sizes of the comprehensive risk coefficient.

[0011] Compared with related technologies, the embodiments of this application have at least the following advantages: as the comprehensive risk coefficient increases, that is, the corresponding calibration constant decreases, the target hydraulic braking torque rises faster, and thus the electrical feedback torque can be converted into hydraulic braking torque in a shorter time, so as to improve the lateral stability of the vehicle as soon as possible and reduce the possibility of the vehicle understeer or fishtailing.

[0012] In some possible embodiments, the effective braking system type is Electronic Stability Control (ESC) mode braking, and the distribution of total braking force based on the braking force distribution strategy includes: calculating the front-to-rear axle reference braking force ratio based on the braking I curve and the longitudinal acceleration of the vehicle; determining a dynamic distribution coefficient corresponding to the comprehensive risk coefficient; determining the front-to-rear axle actual braking force ratio based on the front-to-rear axle reference braking force ratio and the dynamic distribution coefficient; and determining the front axle braking force and the rear axle braking force based on the total braking force and the front-to-rear axle actual braking force ratio.

[0013] Compared with related technologies, the embodiments of this application have at least the following advantages: For ESC mode braking, the front and rear axle braking force distribution ratio is dynamically adjusted as needed based on the comprehensive risk coefficient, which can improve the lateral stability of the vehicle and reduce the possibility of understeer or fishtailing. For example, when the comprehensive risk coefficient indicates a high steering risk, increasing the front axle proportion can enhance the front axle lateral stiffness to suppress fishtailing.

[0014] In some possible embodiments, the effective braking system type is brake-by-wire, and the total braking force is distributed based on the braking force distribution strategy as follows: The front-to-rear axle reference braking force ratio is calculated based on the braking I curve and the vehicle's longitudinal acceleration; a dynamic distribution coefficient corresponding to the comprehensive risk coefficient is determined; the front-to-rear axle actual braking force ratio is determined based on the front-to-rear axle reference braking force ratio and the dynamic distribution coefficient; the front axle braking force and rear axle braking force are determined based on the total braking force and the front-to-rear axle actual braking force ratio; a torque compensation coefficient corresponding to the comprehensive risk coefficient is determined, and a roll moment compensation value is determined based on the torque compensation coefficient and the vehicle's lateral acceleration; the front axle torque compensation value and rear axle torque compensation value are determined based on the roll moment compensation value and the vehicle's mass and wheelbase parameters; the braking force of the left front wheel and the right front wheel are determined based on the front axle torque compensation value and the front axle braking force; and the braking force of the left rear wheel and the right rear wheel are determined based on the rear axle torque compensation value and the rear axle braking force.

[0015] Compared with related technologies, the embodiments of this application have at least the following advantages: For brake-by-wire, the independent wheel-end braking force of the four wheels is determined based on the comprehensive risk coefficient, which can make the braking force of each wheel accurately match its current lateral force reserve, thereby improving the lateral stability of the vehicle and reducing the possibility of the vehicle understeer or fishtailing.

[0016] Secondly, embodiments of this application also provide a vehicle braking control method, the method comprising: acquiring the vehicle speed and / or the road surface adhesion coefficient of the road on which the vehicle travels, and determining a vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient; acquiring the steering wheel angle and steering angular velocity of the vehicle, and determining a steering intention risk coefficient based on the steering wheel angle and steering angular velocity; determining a comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient; if the comprehensive risk coefficient meets a preset risk benchmark and the vehicle is in a preset braking condition, performing vehicle braking using a first braking strategy and a second braking strategy; wherein, the first braking strategy comprises: performing an electro-hydraulic torque conversion operation, determining a target electro-regenerative torque and a target hydraulic braking torque, the electro-hydraulic torque conversion operation comprising gradually reducing the electro-regenerative torque according to a preset rule and gradually... The hydraulic braking torque is gradually increased while maintaining the sum of the electro-regenerative torque and the hydraulic braking torque equal to the total braking torque. The total braking torque is determined based on the target braking deceleration corresponding to the preset braking condition. The preset rule includes determining the target hydraulic braking torque based on the total braking torque and a preset function. The target electro-regenerative torque is determined based on the target hydraulic braking torque and the total braking torque. The preset function includes a time independent variable and a calibration constant corresponding to the comprehensive risk coefficient. The second braking strategy includes: obtaining the type of braking system that is effective for the vehicle; determining a braking torque distribution strategy based on the braking system type; distributing the hydraulic braking torque based on the braking torque distribution strategy; and performing vehicle braking based on the braking torque distribution result. The braking torque distribution strategy includes adjusting the braking torque distribution ratio between the front axle and the rear axle based on the comprehensive risk coefficient.

[0017] Compared with related technologies, the embodiments of this application have at least the following advantages: A comprehensive risk coefficient is established based on multiple factors including steering wheel angle, steering angular velocity, vehicle speed, and road surface adhesion coefficient to comprehensively reflect the vehicle's steering risk. This comprehensive risk coefficient is used to determine whether to perform electro-hydraulic torque conversion, upgrading it from passively responding to braking requests to actively predicting steering instability trends. This improves vehicle driving safety. Furthermore, by performing electro-hydraulic torque conversion under high-risk steering conditions, the single-axle electro-regenerative torque distribution is switched to front-rear hydraulic braking torque distribution, avoiding the impact of single-axle electro-regenerative braking on vehicle yaw stability under high-risk steering conditions. This improves vehicle lateral stability, reduces the possibility of understeer or fishtailing, and suppresses [unclear - possibly related to torque conversion]. The possibility of understeer or fishtailing makes the vehicle stability control system less likely to activate, reducing the frequency of its intervention. This reduces the cumulative activation time of the stability control system throughout the vehicle's lifespan, minimizing conditions with significant yaw rate overshoot and helping to suppress yaw rate overshoot. Furthermore, the distribution ratio of hydraulic braking torque between the front and rear axles can be adjusted based on a comprehensive risk factor, further improving the vehicle's lateral stability. This is applicable to different braking system types, allowing for different hydraulic braking torque distribution adjustment strategies, resulting in higher yaw control precision and further ensuring vehicle stability and safety. By dynamically adjusting the distribution ratio of hydraulic braking torque between the front and rear axles, the frequency of intervention by the vehicle stability control system can be further reduced.

[0018] Thirdly, embodiments of this application also provide a vehicle braking control device, comprising: a first determining module, configured to acquire the vehicle speed and / or the road surface adhesion coefficient of the road on which the vehicle travels, and to determine a vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient; a second determining module, configured to acquire the steering wheel angle and steering angular velocity of the vehicle, and to determine a steering intention risk coefficient based on the steering wheel angle and steering angular velocity; a third determining module, configured to determine a comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient; and a braking control module, configured to perform vehicle braking using a first braking strategy or a second braking strategy if the comprehensive risk coefficient meets a preset risk benchmark and the vehicle is in a preset braking condition; wherein the first braking strategy includes: performing an electro-hydraulic torque conversion operation, determining a target electro-regenerative torque and a target hydraulic braking torque, and performing vehicle braking based on the target electro-regenerative torque and the target hydraulic braking torque, wherein the electro-hydraulic torque conversion... The braking operation includes gradually reducing the electro-regenerative torque and gradually increasing the hydraulic braking torque according to preset rules, while maintaining the sum of the electro-regenerative torque and the hydraulic braking torque equal to the total braking torque. The total braking torque is determined based on the target braking deceleration corresponding to the preset braking condition. The preset rules include determining the target hydraulic braking torque based on the total braking torque and a preset function. The target electro-regenerative torque is determined based on the target hydraulic braking torque and the total braking torque. The preset function includes a time independent variable and a calibration constant corresponding to the comprehensive risk coefficient. The second braking strategy includes: obtaining the type of braking system that is effective for the vehicle, determining a braking force distribution strategy based on the braking system type, distributing the total braking force based on the braking force distribution strategy, and performing vehicle braking based on the braking force distribution result. The total braking force is determined based on the target braking deceleration corresponding to the preset braking condition. The braking force distribution strategy includes adjusting the braking force distribution ratio between the front axle and the rear axle based on the comprehensive risk coefficient.

[0019] Fourthly, embodiments of this application also provide a vehicle, which includes a vehicle braking system, a controller, and a memory. The memory is used to store instructions, and the controller is used to call the instructions in the memory to execute the vehicle braking control method as described in the first aspect, or to execute the vehicle braking control method as described in the second aspect.

[0020] Fifthly, embodiments of this application also provide a computer-readable storage medium that stores computer instructions that, when executed on a controller, cause the controller to perform a vehicle braking control method as described in the first aspect, or a vehicle braking control method as described in the second aspect.

[0021] The technical effects achieved by the third aspect are similar to those achieved by the corresponding technical means in the first aspect, and the technical effects achieved by the fourth and fifth aspects are similar to those achieved by the corresponding technical means in the first / second aspect. They will not be elaborated further here. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a vehicle braking control system provided in an embodiment of this application.

[0023] Figure 2 A flowchart illustrating the steps of a vehicle braking control method provided in an embodiment of this application.

[0024] Figure 3 A flowchart illustrating the steps of a vehicle braking control method provided in another embodiment of this application.

[0025] Figure 4 A flowchart illustrating the steps of a vehicle braking control method provided in another embodiment of this application.

[0026] Figure 5 A functional block diagram of a vehicle braking control device provided in an embodiment of this application.

[0027] Figure 6 This is a schematic diagram of the structure of a vehicle provided in one embodiment of this application. Detailed Implementation

[0028] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0029] The following description sets forth many specific details to provide a full understanding of this application. The described embodiments are only some, not all, of the embodiments of this application.

[0030] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application's specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0031] It should be further noted that, in this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0032] In this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and drawings of this application are used to distinguish similar objects, not to describe a specific order or sequence.

[0033] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0034] Due to cost considerations, some new energy vehicles are either front-wheel drive or rear-wheel drive. For front-wheel drive vehicles, the front wheels can be braked using either electro-regenerative braking or hydraulic braking, while the rear wheels are braked hydraulically. For rear-wheel drive vehicles, the rear wheels can be braked using either electro-regenerative braking or hydraulic braking, while the front wheels are braked hydraulically. In actual braking control strategies, electro-regenerative braking generally takes precedence. However, electro-regenerative braking can cause the combined tire force on that axle to approach the friction circle limit, resulting in low lateral force reserve. When the driver performs a steering maneuver, this axle, due to insufficient lateral stiffness, cannot effectively support the vehicle's yaw response. Especially in emergency or rapid steering conditions, this can easily induce understeer or fishtailing, not only reducing handling stability but also potentially threatening driving safety.

[0035] Therefore, this application provides a vehicle braking control method that can solve the problem of poor handling stability of existing vehicles under braking conditions.

[0036] Figure 1 This is a schematic diagram of the vehicle braking control system provided in the embodiments of this application.

[0037] The vehicle braking control system may include a sensing module 101, a vehicle braking system 102, and a control module 103. The vehicle braking control system may be integrated into the vehicle, which may be a front-wheel drive vehicle or a rear-wheel drive vehicle. The following example uses a rear-wheel drive pure electric vehicle.

[0038] The sensing module 101 serves as the sensing layer for vehicle braking control, enabling the sensing of vehicle-related information. The information sensed by the sensing module 101 can be transmitted to the control module 103 for processing. Vehicle-related information may include information about the vehicle itself, or it may include information about the road surface on which the vehicle is traveling. For example, vehicle-related information includes, but is not limited to, brake pedal travel, vehicle speed, steering wheel angle, steering angular velocity, longitudinal acceleration, and lateral acceleration. Information about the road surface on which the vehicle is traveling may include the road surface adhesion coefficient.

[0039] For example, the sensing module 101 may include cameras, sensors, etc., deployed in the vehicle. For instance, brake pedal travel, vehicle speed, steering wheel angle, steering angular velocity, longitudinal acceleration, and lateral acceleration can all be acquired by sensors deployed in the vehicle. The road surface adhesion coefficient can be estimated based on the extended Kalman filter (EKF) described in relevant technologies. Alternatively, the road surface adhesion coefficient can also be estimated using tire noise, such as by collecting tire noise through a microphone; the sharper the sound, the more slippery the road surface, and using this to estimate the road surface adhesion coefficient based on a preset noise-road surface adhesion coefficient mapping table.

[0040] The vehicle braking system 102 serves as the execution layer for vehicle braking control, and is used to achieve vehicle braking. For example, the vehicle braking system 102 may include actuators based on electro-regenerative braking and actuators based on hydraulic braking.

[0041] As the decision-making layer for vehicle braking control, the control module 103 can control the vehicle braking system 102 based on the sensing information from the sensing module 101 when the vehicle is under preset braking conditions, in order to perform corresponding vehicle braking operations. For example, preset braking conditions may include coasting energy regenerative braking conditions and light braking energy regenerative braking conditions. The control module 103 can perform the distribution of total braking torque / total braking force based on the sensing information from the sensing module 101. The distributed braking torque / braking force can be sent to the vehicle braking system 102 in the form of braking control commands to perform corresponding vehicle braking operations.

[0042] For example, coasting energy regenerative braking can mean that there is no input from the accelerator pedal or the brake pedal, and the vehicle decelerates solely through the feedback force from the motor. Light braking energy regenerative braking can mean that the brake pedal is below a preset brake opening threshold. In this case, the vehicle generally also decelerates solely through the feedback force from the motor. The preset brake opening threshold can be set to 0.4g (g is the acceleration due to gravity, 0.4g ≈ 3.92 m / s²).

[0043] For example, the total braking torque / total braking force can be determined based on the brake pedal travel or the maximum motor feedback parameters under the current energy recovery mode (such as coasting energy recovery condition). The specific method for determining the total braking torque / total braking force can be achieved using methods described in relevant technologies. This application embodiment does not involve any improvement to the method for determining the total braking torque / total braking force. The control module 103 may include a chip with data processing / control functions. For example, the chip may be the vehicle's original Electronic Control Unit (ECU). Alternatively, the control module 103 may also be implemented by the vehicle's original vehicle controller. This application embodiment does not limit the chip included in the control module 103; the original control chip of the vehicle may be reused, or it may be a control chip specifically deployed to realize vehicle braking decisions.

[0044] The following is a detailed description of how to implement the vehicle braking control method provided in this application.

[0045] Figure 2 This is a schematic flowchart illustrating a vehicle braking control method provided in an embodiment of this application. Figure 2 As shown, this vehicle braking control method can be applied to a vehicle braking control system, for example, the vehicle braking control system may include at least Figure 1 The sensor module, vehicle braking system, and control module shown herein, and the vehicle braking control method can be derived from... Figure 1 The control module shown executes the steps. The steps in this embodiment can be adjusted or combined according to actual needs, and this embodiment does not limit this. The vehicle braking control method may specifically include: Step S210: Obtain the vehicle speed and / or the road surface adhesion coefficient of the road on which the vehicle travels, and determine the vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient.

[0046] In some embodiments, vehicle speed can be sensed by speed sensors deployed on the vehicle, and the road surface adhesion coefficient can be estimated using data collected by sensors deployed on the vehicle and the EKF algorithm. For example, sensor data used to estimate the road surface adhesion coefficient includes, but is not limited to, longitudinal driving force / braking force, wheel speed collected by wheel speed sensors, longitudinal acceleration collected by inertial measurement unit (IMU), and steering wheel angle collected by steering wheel angle sensor. The control module can obtain the vehicle speed and the road surface adhesion coefficient of the road on which the vehicle is traveling by acquiring data collected by each sensor.

[0047] In some embodiments, the control module can determine the vehicle driving risk coefficient based on vehicle speed or road surface adhesion coefficient, or it can determine the vehicle driving risk coefficient based on both vehicle speed and road surface adhesion coefficient. The vehicle driving risk coefficient can be used to characterize the vehicle's yaw stability margin. A larger vehicle driving risk coefficient indicates a smaller yaw stability margin, and vice versa. The vehicle driving risk coefficient can be set between 0 and 1. For example, vehicle speed can be divided into multiple speed ranges, with different speed ranges corresponding to different vehicle driving risk coefficients, and the same speed range corresponding to the same vehicle driving risk coefficient. For example, five speed ranges can correspond to five different vehicle driving risk coefficients: [0–20 km / h), [20 km / h–40 km / h), [40 km / h–60 km / h), [60 km / h–80 km / h), and ≥80 km / h. The higher the vehicle speed, the higher the corresponding vehicle driving risk coefficient. For example, the road surface adhesion coefficient can be divided into multiple intervals. Different intervals of road surface adhesion coefficient correspond to different vehicle driving risk coefficients, and the same interval of road surface adhesion coefficient corresponds to the same vehicle driving risk coefficient. For example, if the road surface adhesion coefficient is divided into four intervals, it corresponds to four different vehicle driving risk coefficients: ≤0.3, (0.3–0.5], (0.5–0.7], and >0.7. The smaller the road surface adhesion coefficient, the greater the corresponding vehicle driving risk coefficient.

[0048] For example, if the vehicle driving risk coefficient is determined based on vehicle speed and road surface adhesion coefficient, a first weighting coefficient can be pre-set for vehicle speed and a second weighting coefficient can be set for road surface adhesion coefficient (the sum of the first and second weighting coefficients equals 1). The comprehensive vehicle driving risk coefficient is then calculated using a weighted method. The correspondence between the vehicle driving risk coefficient and vehicle speed and / or road surface adhesion coefficient can be pre-stored in the vehicle database, facilitating quick determination of the vehicle driving risk coefficient by looking up a table later.

[0049] For example, the vehicle driving risk coefficient can be determined by querying the first mapping table based on the vehicle speed range and the road surface adhesion coefficient range. The first mapping table can include the mapping relationship between multiple combinations of vehicle speed ranges and road surface adhesion coefficient ranges and multiple vehicle driving risk coefficients. Each combination of vehicle speed range and road surface adhesion coefficient range can correspond to a vehicle driving risk coefficient.

[0050] Step S220: Obtain the vehicle's steering wheel angle and steering angular velocity, and determine the steering intention risk coefficient based on the steering wheel angle and steering angular velocity.

[0051] In some embodiments, the vehicle's steering wheel angle and steering angular velocity can also be acquired by relevant sensors deployed on the vehicle. The control module can acquire the vehicle's steering wheel angle and steering angular velocity by communicating with the relevant sensors.

[0052] In some embodiments, the steering wheel angle and steering angular velocity can also be divided into multiple intervals. By setting different combinations of steering wheel angle and steering angular velocity intervals, different steering intention risk coefficients are corresponding to each interval. The steering intention risk coefficient can be used to characterize the degree of steering aggression. The larger the steering intention risk coefficient, the greater the degree of steering aggression, and vice versa. The steering intention risk coefficient can be set between 0 and 1. The correspondence between the steering intention risk coefficient and the steering wheel angle and steering angular velocity can be pre-stored in the vehicle for easy lookup and quick determination of the steering intention risk coefficient later.

[0053] For example, the steering wheel angle can be divided into multiple angle intervals, with different intervals corresponding to different first risk coefficients. The same first risk coefficient applies to the same angle interval, and the larger the steering wheel angle, the larger the corresponding first risk coefficient. Similarly, the steering angular velocity can be divided into multiple angular velocity intervals, with different angular velocity intervals corresponding to different second risk coefficients. The same second risk coefficient applies to the same angular velocity interval, and the larger the corresponding second risk coefficient applies. By assigning a third weighting coefficient to the steering wheel angle and a fourth weighting coefficient to the steering angular velocity (the sum of the third and fourth weighting coefficients equals 1), a weighted calculation of the first and second risk coefficients can be performed to obtain the steering intention risk coefficient. Using this method, the steering intention risk coefficient corresponding to each combination of angle intervals and angular velocity intervals can be determined.

[0054] For example, based on the steering wheel angle range to which the steering wheel angle belongs and the steering angular velocity range to which the steering angular velocity belongs, a second mapping table can be consulted to determine the steering intention risk coefficient. The second mapping table may include the mapping relationship between multiple combinations of steering wheel angle ranges and steering angular velocity ranges and multiple steering intention risk coefficients, with each combination of steering wheel angle ranges and steering angular velocity ranges corresponding to a steering intention risk coefficient.

[0055] Step S230: Determine the comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient.

[0056] In some embodiments, after determining the vehicle driving risk coefficient and the steering intention risk coefficient, a comprehensive risk coefficient can be further determined based on these coefficients. For example, the comprehensive risk coefficient can be calculated by substituting the vehicle driving risk coefficient and the steering intention risk coefficient into a pre-constructed formula. Another example is using a preset nonlinear function, where the vehicle state risk coefficient and the driving intention risk coefficient can be input into the preset nonlinear function to determine the comprehensive risk coefficient. This preset nonlinear function has the characteristic that the output changes abruptly when the input increases to a threshold.

[0057] For example, the input parameters include the vehicle driving risk coefficient K1 and the steering intention risk coefficient K2, and the output is the comprehensive risk coefficient RISK = LUT(K1, K2). The value of RISK is between 0 and 1. As the vehicle driving risk coefficient and the steering intention risk coefficient increase, the comprehensive risk coefficient also increases. The value of RISK can be used to characterize the final instability probability under the combined effect of the road surface, vehicle and driver intention. For example, when K1>0.7 and K2>0.7, the value of RISK can grow exponentially to simulate the critical instability mutation and avoid the conservatism of risk estimation caused by linear superposition.

[0058] In some embodiments, the correspondence between the comprehensive risk coefficient and the vehicle driving risk coefficient and the steering intention risk coefficient can be pre-stored in the vehicle, so that the comprehensive risk coefficient can be quickly determined by looking up the table later.

[0059] Step S240: If the comprehensive risk coefficient meets the preset risk benchmark and the vehicle is in the preset braking condition, the first braking strategy is adopted to perform vehicle braking.

[0060] In some embodiments, the comprehensive risk coefficient meeting the preset risk benchmark can mean that the comprehensive risk coefficient is greater than a first preset threshold and the duration is greater than a preset duration. The preset braking conditions include, but are not limited to, coasting energy regeneration conditions and light braking energy regeneration conditions. The first preset threshold and the preset duration can be set according to the actual vehicle control requirements, and this application embodiment does not limit them. For example, the first preset threshold can be set to 0.85, and the preset duration can be set to 20ms.

[0061] In some embodiments, the first braking strategy may include: performing an electro-hydraulic torque conversion operation to determine a target electro-regenerative torque and a target hydraulic braking torque, and performing vehicle braking based on the target electro-regenerative torque and the target hydraulic braking torque. The electro-hydraulic torque conversion operation may include gradually decreasing the electro-regenerative torque and gradually increasing the hydraulic braking torque according to a preset rule, while maintaining the sum of the electro-regenerative torque and the hydraulic braking torque equal to the total braking torque. The total braking torque may be determined based on a target braking deceleration corresponding to a preset braking condition. The preset rule may include determining the target hydraulic braking torque based on the total braking torque and a preset function. The target electro-regenerative torque may be determined based on the target hydraulic braking torque and the total braking torque. The preset function may include a calibration constant corresponding to a time independent variable and a comprehensive risk coefficient.

[0062] For example, the target hydraulic braking torque can be determined based on the following formula: T_hyd(t) = T_total × (1 - ), where T_hyd(t) is the target hydraulic braking torque, T_total is the total braking torque, and t is the time variable. As a calibration constant, different calibration constants can correspond to different interval sizes for the comprehensive risk coefficient. For example, the comprehensive risk coefficient can be divided into 10 intervals (0.0–0.1, 0.1–0.2, …, 0.9–1.0), each interval corresponding to a preset calibration constant (in milliseconds). For each interval, as the value of the interval increases, the corresponding calibration constant... This can decrease accordingly, such as when the comprehensive risk coefficient ∈ (0.8, 0.9], the corresponding calibration constant. =110ms, comprehensive risk coefficient ∈(0.9, 1.0], corresponding calibration constant =75ms. With the calibration constant... The decrease in the overall risk coefficient (i.e., the increase in the comprehensive risk coefficient) leads to a faster increase in the target hydraulic braking torque T_hyd(t), which means that the electrical feedback torque is converted into hydraulic braking torque in a shorter time, so as to improve the lateral stability of the vehicle as soon as possible and reduce the possibility of the vehicle understeer or fishtailing.

[0063] In some embodiments, for T_hyd(t) = T_total × (1 - In this context, when t=0, T_hyd(t) equals 0, meaning that at the initial moment, the target electro-hydraulic braking torque equals the total braking torque, and the target hydraulic braking torque equals 0. As t increases, the target hydraulic braking torque gradually increases, and the target electro-hydraulic braking torque gradually decreases (target electro-hydraulic braking torque = total braking torque - target hydraulic braking torque) until the target hydraulic braking torque approaches the total braking torque, and the target electro-hydraulic braking torque approaches 0. That is, the electro-hydraulic torque conversion process is to gradually decrease the electro-hydraulic braking torque and gradually increase the hydraulic braking torque to switch the electro-hydraulic braking torque to hydraulic braking torque. The hydraulic braking torque can be distributed to the front and rear axles according to a preset ratio, for example, 65% for the front axle and 35% for the rear axle. This application does not limit the preset ratio and can set it according to the actual vehicle simulation test results.

[0064] In some embodiments, the control module can send the target electro-regenerative torque to the motor controller to perform electro-regenerative braking. The control module can also send the target hydraulic braking torque to the electronic stability controller or brake-by-wire controller to perform hydraulic braking. This application embodiment, by performing electro-hydraulic torque conversion under high-risk steering conditions, can avoid the impact of single-axle electro-regenerative braking on vehicle yaw stability under high-risk steering conditions. By switching the single-axle electro-regenerative torque distribution to front-rear hydraulic braking torque distribution, the lateral stability of the vehicle can be improved, reducing the possibility of understeer or fishtailing.

[0065] In some embodiments, if the overall risk coefficient does not meet the preset risk benchmark or the vehicle is not in a preset braking condition, the original strategy can be used to control the vehicle. For example, if the overall risk coefficient does not meet the preset risk benchmark and the vehicle is in a preset braking condition, the original braking strategy is used to perform vehicle braking (e.g., electro-hydraulic torque conversion is not performed, and vehicle braking is performed based on electro-regenerative torque). This application embodiment can achieve energy recovery and reduce energy consumption by using electro-regenerative torque braking during normal driving, and intervene with hydraulic braking when a high-risk steering is detected to ensure vehicle driving stability and safety.

[0066] The aforementioned vehicle braking control method establishes a comprehensive risk coefficient—a quantitative indicator that comprehensively reflects the vehicle's steering risk—based on multiple factors including steering wheel angle, steering angular velocity, vehicle speed, and road surface adhesion coefficient. This comprehensive risk coefficient is used to determine whether to execute electro-hydraulic torque conversion, upgrading it from a passive response to braking requests to an active prediction of steering instability trends. This improves vehicle driving safety. Furthermore, by performing electro-hydraulic torque conversion under high-risk steering conditions, switching the single-axle electro-regenerative torque distribution to front-rear hydraulic braking torque distribution, the impact of single-axle electro-regenerative braking on vehicle yaw stability under high-risk steering conditions can be avoided, thereby improving lateral stability and reducing the likelihood of understeer or fishtailing. Suppressing understeer or fishtailing through electro-hydraulic torque conversion makes the vehicle stability control system less likely to activate, reducing its intervention frequency and thus decreasing the cumulative activation time of the system throughout the vehicle's lifespan. This reduces conditions with large yaw rate overshoot and helps suppress yaw rate overshoot.

[0067] Please see Figure 3 This is a flowchart illustrating a vehicle braking control method according to another embodiment of this application. The vehicle braking control method can also be implemented by... Figure 1 The control module shown executes the vehicle braking control method, which is applicable to scenarios where regenerative braking is not used or where regenerative braking functionality is not available. The steps and flow of this application embodiment can be adjusted or combined according to actual needs; this application embodiment does not limit this. Specifically, the vehicle braking control method may include: Step S310: Obtain the vehicle speed and / or the road surface adhesion coefficient of the road on which the vehicle is traveling, and determine the vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient.

[0068] The content of step S310 in this embodiment is similar to that of step S210 in the previous embodiment. To avoid repetition, it will not be described again here.

[0069] Step S320: Obtain the vehicle's steering wheel angle and steering angular velocity, and determine the steering intention risk coefficient based on the steering wheel angle and steering angular velocity.

[0070] The content of step S320 in this embodiment is similar to that of step S220 in the previous embodiment. To avoid repetition, it will not be described again here.

[0071] Step S330: Determine the comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient.

[0072] The content of step S330 in this embodiment is similar to that of step S230 in the previous embodiment. To avoid repetition, it will not be described again here.

[0073] Step S340: If the comprehensive risk coefficient meets the preset risk benchmark and the vehicle is in the preset braking condition, the second braking strategy is adopted to perform vehicle braking.

[0074] In some embodiments, the preset braking condition may refer to a braking condition that is more likely to induce the vehicle to enter a large yaw state, such as applying brakes while driving in a curve or applying brakes when the road surface adhesion coefficients of the left and right wheels are inconsistent. The second braking strategy may refer to a braking force classification strategy based on calculating a reference braking distribution value and adjusting the dynamic coefficient based on the I-curve. The second braking strategy can be applied to braking force distribution under different braking system types. For example, different braking system types may include Electronic Stability Control (ESC) mode braking and brake-by-wire braking. The control module can automatically identify the type of braking system that is active in the vehicle and call the relevant algorithm to distribute braking force. For example, for a vehicle that has both ESC mode braking and brake-by-wire braking, the control module can identify the type of braking system that is active in the vehicle based on the methods described in relevant technologies. For another example, the second braking strategy includes: obtaining the type of braking system that is active in the vehicle, and determining a braking force distribution strategy based on the braking system type; distributing the total braking force based on the braking force distribution strategy, and performing vehicle braking based on the braking force distribution result. The total braking force can be determined based on the target braking deceleration corresponding to the preset braking conditions, such as by determining the total braking force corresponding to the target braking deceleration in a manner described in relevant technical documents. The braking force distribution strategy may include adjusting the braking force distribution ratio between the front axle and the rear axle based on a comprehensive risk coefficient. If the comprehensive risk coefficient meets the preset risk benchmark, the front axle braking force distribution ratio can be increased to enhance the front axle lateral stiffness and suppress fishtailing.

[0075] Taking ESC mode braking as an example, the distribution of total braking force based on the braking force distribution strategy can specifically include: calculating the front-to-rear axle reference braking force ratio based on the braking I-curve and the vehicle's longitudinal acceleration; determining the dynamic distribution coefficient corresponding to the comprehensive risk coefficient; determining the front-to-rear axle actual braking force ratio based on the front-to-rear axle reference braking force ratio and the dynamic distribution coefficient; and determining the front axle braking force and the rear axle braking force based on the total braking force and the front-to-rear axle actual braking force ratio. After determining the front axle braking force and the rear axle braking force, the front axle braking force can be evenly distributed to the two front wheels, and the rear axle braking force can be evenly distributed to the two rear wheels.

[0076] Specifically, the formula for calculating the current front-to-rear axle reference braking force ratio β_I based on the I curve can be: β_I = [(L- a) ×g+h×a_x] / (a×gh×a_x). Where: a_x is the vehicle's current longitudinal acceleration, L is the vehicle's wheelbase, a is the distance from the vehicle's center of gravity to the front axle, La is the distance from the vehicle's center of gravity to the rear axle, h is the vehicle's center of gravity's ground clearance, and g is the acceleration due to gravity. The vehicle's longitudinal direction can refer to the forward and backward travel direction from the rear to the front of the vehicle, and the vehicle's lateral direction can refer to the direction perpendicular to the longitudinal direction, i.e., the left and right lateral directions of the vehicle.

[0077] Determining the dynamic allocation coefficient corresponding to the comprehensive risk coefficient can be achieved by introducing a calibrable dynamic allocation coefficient k_bias. The value of k_bias is determined by looking up a table based on the comprehensive risk coefficient. For example, the comprehensive risk coefficient can be divided into 10 intervals (0.0–0.1, 0.1–0.2, …, 0.9–1.0), with each interval corresponding to a pre-calibrated k_bias value. For instance, the range of the 10 pre-calibrated k_bias values ​​is 0.85 to 1.25. For the comprehensive risk coefficient in different intervals, the k_bias value increases as the comprehensive risk coefficient increases.

[0078] In some embodiments, the actual braking force ratio β_actual between the front and rear axles can be determined based on the following formula: β_actual = k_bias × β_I.

[0079] After determining the actual braking force ratio between the front and rear axles, the front axle braking force F_f and the rear axle braking force F_r can be determined based on the following formulas: F_f = F_total × β_actual / (1 + β_actual); F_r = F_total - F_f, where F_total is the total braking force.

[0080] Taking brake-by-wire as the effective braking system type as an example, the distribution of total braking force based on the braking force distribution strategy may include: calculating the front-to-rear axle reference braking force ratio based on the braking I-curve and the vehicle's longitudinal acceleration; determining the dynamic distribution coefficient corresponding to the comprehensive risk coefficient; determining the front-to-rear axle actual braking force ratio based on the front-to-rear axle reference braking force ratio and the dynamic distribution coefficient; determining the front axle braking force and the rear axle braking force based on the total braking force and the front-to-rear axle actual braking force ratio; determining the torque compensation coefficient corresponding to the comprehensive risk coefficient, and determining the roll torque compensation value based on the torque compensation coefficient and the vehicle's lateral acceleration; determining the front axle torque compensation value and the rear axle torque compensation value based on the roll torque compensation value and the vehicle's mass and wheelbase parameters; determining the braking force of the left front wheel and the right front wheel based on the front axle torque compensation value and the front axle braking force; and determining the braking force of the left rear wheel and the right rear wheel based on the rear axle torque compensation value and the rear axle braking force. This method enables the output of independent wheel-end braking force for all four wheels, ensuring that the braking force of each wheel is precisely matched with its current lateral force reserve, thereby further improving vehicle driving safety.

[0081] Specifically, the front axle braking force F_f and the rear axle braking force F_r can be determined as described above. The torque compensation coefficient corresponding to the comprehensive risk coefficient can be determined by introducing a calibrable torque compensation coefficient k_lat. The value of k_lat is determined by looking up a table based on the comprehensive risk coefficient. For example, the comprehensive risk coefficient can be divided into 10 intervals (0.0–0.1, 0.1–0.2, …, 0.9–1.0), with each interval corresponding to a pre-calibrated k_lat value. For instance, the range of the 10 pre-calibrated k_lat values ​​is 0.2–1.0. For different intervals of the comprehensive risk coefficient, as the comprehensive risk coefficient increases, the corresponding k_lat value becomes larger.

[0082] After determining the torque compensation coefficient, the roll torque compensation value ΔF_lat can be determined based on the torque compensation coefficient and the vehicle's lateral acceleration using the following formula: ΔF_lat = k_lat × |a_y|, where a_y is the vehicle's current lateral acceleration and |a_y| is the absolute value of a_y.

[0083] After determining the roll moment compensation value, the front axle moment compensation value ΔF_lat_f and the rear axle moment compensation value ΔF_lat_r can be determined based on the following formulas: ΔF_lat_f = k_f × ΔF_lat ×m, ΔF_lat_r = k_r ×ΔF_lat ×m, k_f = (L - a) / L; k_r = a / L, where m is the total vehicle mass.

[0084] In some embodiments, assuming the vehicle is turning left (a_y>0) and the right wheel is the outer wheel, after determining the front axle torque compensation value, the braking force F_fl of the left front wheel and the braking force F_fr of the right front wheel can be determined based on the following algorithm: F_fl = F_f / 2 - ΔF_lat_f, F_fr = F_f / 2 + ΔF_lat_f; after determining the rear axle torque compensation value, the braking force F_rl of the left rear wheel and the braking force F_rr of the right rear wheel can be determined based on the following algorithm: F_rl = F_r / 2 - ΔF_lat_r, F_rr = F_r / 2 + ΔF_lat_r.

[0085] In some embodiments, after determining the target braking force (F_fl, F_fr, F_rl, F_rr) for each wheel, the brake-by-wire controller uses the target braking force of each wheel as the tracking target, and combines the actual braking state of the wheel end with real-time feedback to perform closed-loop braking force adjustment in order to achieve vehicle braking.

[0086] In some embodiments, if the overall risk coefficient does not meet the preset risk benchmark or the vehicle is not in the preset braking condition, the original strategy can be used to control the vehicle. For example, the front and rear axle braking force can be distributed according to the default distribution strategy.

[0087] The aforementioned vehicle braking control method establishes a comprehensive risk coefficient—a quantitative indicator that comprehensively reflects the vehicle's steering risk—based on multiple factors including steering wheel angle, steering angular velocity, vehicle speed, and road surface adhesion coefficient. This comprehensive risk coefficient is used to determine whether to adjust the front-to-rear axle braking force distribution ratio, thereby improving the vehicle's lateral stability, reducing the likelihood of understeer or fishtailing, and is applicable to two types of brake actuators. Different braking force distribution adjustment strategies are employed for different actuators, resulting in higher yaw control precision and further ensuring vehicle stability and safety. Furthermore, by dynamically adjusting the front-to-rear axle braking force distribution ratio to suppress understeer or fishtailing, the vehicle stability control system becomes less prone to activation, reducing its intervention frequency and thus decreasing the cumulative activation time of the system throughout the vehicle's lifespan. This reduces the occurrence of conditions with significant yaw rate overshoot and helps suppress yaw rate overshoot.

[0088] In some embodiments, after determining the comprehensive risk coefficient, if the comprehensive risk coefficient meets the preset risk benchmark and the vehicle is under preset braking conditions, the vehicle braking can be performed by selecting either the first braking strategy or the second braking strategy based on the current braking scenario.

[0089] For example, for vehicles without regenerative braking, a second braking strategy can be used to perform vehicle braking when the overall risk coefficient meets the preset risk benchmark and the vehicle is under preset braking conditions.

[0090] In some embodiments, after vehicle braking is performed using a first braking strategy or a second braking strategy, if the vehicle driving risk is eliminated (e.g., the overall risk coefficient decreases to below a first preset threshold and remains below it for a certain period of time), the vehicle can revert to the original strategy for vehicle control. For example, after vehicle braking is performed using the first braking strategy, if the vehicle driving risk is eliminated, the vehicle can smoothly transition from hydraulic braking torque to electro-regenerative torque according to a preset recovery slope. By gradually reducing the hydraulic braking torque and gradually increasing the electro-regenerative torque, the total braking torque remains continuous and stable, thereby avoiding sudden changes in braking torque and improving the smoothness of vehicle braking. The magnitude of the recovery slope can be calibrated according to the vehicle's state parameters, taking into account both braking smoothness and energy recovery efficiency. As another example, after vehicle braking is performed using the second braking strategy, if the vehicle driving risk is eliminated, braking force distribution can be performed using a default front-to-rear axle braking force distribution ratio (e.g., 6:4).

[0091] like Figure 4 The diagram shown is a flowchart illustrating a vehicle braking control method according to another embodiment of this application. The vehicle braking control method can also be implemented by... Figure 1 The control module shown executes the steps. The steps in this embodiment can be adjusted or combined according to actual needs, and this embodiment does not limit this. The vehicle braking control method may specifically include: Step S410: Obtain the vehicle speed and / or the road surface adhesion coefficient of the road on which the vehicle is traveling, and determine the vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient.

[0092] The content of step S410 in this embodiment is similar to that of step S210 in the previous embodiment. To avoid repetition, it will not be described again here.

[0093] Step S420: Obtain the vehicle's steering wheel angle and steering angular velocity, and determine the steering intention risk coefficient based on the steering wheel angle and steering angular velocity.

[0094] The content of step S420 in this embodiment is similar to that of step S220 in the previous embodiment. To avoid repetition, it will not be described again here.

[0095] Step S430: Determine the comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient.

[0096] The content of step S430 in this embodiment is similar to that of step S230 in the previous embodiment. To avoid repetition, it will not be described again here.

[0097] Step S440: If the comprehensive risk coefficient meets the preset risk benchmark and the vehicle is in the preset braking condition, the first braking strategy and the second braking strategy are used to perform vehicle braking.

[0098] In some embodiments, the comprehensive risk coefficient meeting the preset risk benchmark can mean that the comprehensive risk coefficient is greater than a first preset threshold and the duration is greater than a preset duration. The preset braking conditions include, but are not limited to, coasting energy regeneration conditions and light braking energy regeneration conditions. The first preset threshold and the preset duration can be set according to the actual vehicle control requirements, and this application embodiment does not limit them.

[0099] In some embodiments, the first braking strategy may include: performing an electro-hydraulic torque conversion operation to determine a target electro-regenerative torque and a target hydraulic braking torque, and performing vehicle braking based on the target electro-regenerative torque and the target hydraulic braking torque. The electro-hydraulic torque conversion operation may include gradually decreasing the electro-regenerative torque and gradually increasing the hydraulic braking torque according to a preset rule, while maintaining the sum of the electro-regenerative torque and the hydraulic braking torque equal to the total braking torque. The total braking torque may be determined based on a target braking deceleration corresponding to a preset braking condition. The preset rule may include determining the target hydraulic braking torque based on the total braking torque and a preset function. The target electro-regenerative torque may be determined based on the target hydraulic braking torque and the total braking torque. The preset function may include a calibration constant corresponding to a time independent variable and a comprehensive risk coefficient.

[0100] The second braking strategy may include: obtaining the type of braking system in effect for the vehicle, determining a braking torque distribution strategy based on the braking system type, distributing hydraulic braking torque based on the braking torque distribution strategy, and performing vehicle braking based on the braking torque distribution result. The braking torque distribution strategy includes adjusting the braking torque distribution ratio between the front axle and the rear axle based on a comprehensive risk coefficient. That is, in this embodiment, the electro-hydraulic torque conversion is performed through a first braking strategy, and the converted hydraulic braking torque is distributed through a second braking strategy. The second braking strategy can distribute the hydraulic braking torque after the hydraulic braking torque conversion is completed, or it can distribute the hydraulic braking torque during the hydraulic braking torque conversion process.

[0101] Taking ESC mode braking as an example, the distribution of the converted hydraulic braking torque based on the braking force distribution strategy can specifically include: calculating the front-to-rear axle reference braking force ratio based on the braking I-curve and the vehicle's longitudinal acceleration; determining the dynamic distribution coefficient corresponding to the comprehensive risk coefficient; determining the front-to-rear axle actual braking force ratio based on the front-to-rear axle reference braking force ratio and the dynamic distribution coefficient; and determining the front axle braking force and the rear axle braking force based on the converted hydraulic braking torque and the front-to-rear axle actual braking force ratio. After determining the front axle braking force and the rear axle braking force, the front axle braking force can be evenly distributed to the two front wheels, and the rear axle braking force can be evenly distributed to the two rear wheels.

[0102] Specifically, the formula for calculating the current front-to-rear axle reference braking force ratio β_I based on the I curve can be: β_I = [(L- a) ×g+h×a_x] / (a×gh×a_x). Where: a_x is the vehicle's current longitudinal acceleration, L is the vehicle's wheelbase, a is the distance from the vehicle's center of gravity to the front axle, La is the distance from the vehicle's center of gravity to the rear axle, h is the vehicle's center of gravity's ground clearance, and g is the acceleration due to gravity. The vehicle's longitudinal direction can refer to the forward and backward travel direction from the rear to the front of the vehicle, and the vehicle's lateral direction can refer to the direction perpendicular to the longitudinal direction, i.e., the left and right lateral directions of the vehicle.

[0103] Determining the dynamic allocation coefficient corresponding to the comprehensive risk coefficient can be achieved by introducing a calibrable dynamic allocation coefficient k_bias. The value of k_bias is determined by looking up a table based on the comprehensive risk coefficient. For example, the comprehensive risk coefficient can be divided into 10 intervals (0.0–0.1, 0.1–0.2, …, 0.9–1.0), with each interval corresponding to a pre-calibrated k_bias value. For instance, the range of the 10 pre-calibrated k_bias values ​​is 0.85 to 1.25. For the comprehensive risk coefficient in different intervals, the k_bias value increases as the comprehensive risk coefficient increases.

[0104] In some embodiments, the actual braking force ratio β_actual between the front and rear axles can be determined based on the following formula: β_actual = k_bias × β_I.

[0105] After determining the actual braking force ratio between the front and rear axles, the front axle braking force F_f and the rear axle braking force F_r can be determined based on the following formulas: F_f = F_total' × β_actual / (1 + β_actual); F_r = F_total' - F_f, where F_total' is the braking force corresponding to the converted hydraulic braking torque. The conversion between braking torque and braking force can be performed in accordance with the methods described in relevant technologies. This application does not limit this aspect.

[0106] Taking brake-by-wire as the effective braking system type as an example, the distribution of the converted hydraulic braking torque based on the braking force distribution strategy may include: calculating the front-to-rear axle reference braking force ratio based on the braking I-curve and the vehicle's longitudinal acceleration; determining the dynamic distribution coefficient corresponding to the comprehensive risk coefficient; determining the front-to-rear axle actual braking force ratio based on the front-to-rear axle reference braking force ratio and the dynamic distribution coefficient; determining the front axle braking force and the rear axle braking force based on the converted hydraulic braking torque and the front-to-rear axle actual braking force ratio; determining the torque compensation coefficient corresponding to the comprehensive risk coefficient, and determining the roll moment compensation value based on the torque compensation coefficient and the vehicle's lateral acceleration; determining the front axle torque compensation value and the rear axle torque compensation value based on the roll moment compensation value and the vehicle's mass and wheelbase parameters; determining the braking force of the left front wheel and the right front wheel based on the front axle torque compensation value and the front axle braking force; and determining the braking force of the left rear wheel and the right rear wheel based on the rear axle torque compensation value and the rear axle braking force. This method enables the output of independent wheel-end braking force for all four wheels, ensuring that the braking force of each wheel is precisely matched with its current lateral force reserve, thereby further improving vehicle driving safety.

[0107] Specifically, the front axle braking force F_f and the rear axle braking force F_r can be determined as described above. The torque compensation coefficient corresponding to the comprehensive risk coefficient can be determined by introducing a calibrable torque compensation coefficient k_lat. The value of k_lat is determined by looking up a table based on the comprehensive risk coefficient. For example, the comprehensive risk coefficient can be divided into 10 intervals (0.0–0.1, 0.1–0.2, …, 0.9–1.0), with each interval corresponding to a pre-calibrated k_lat value. For instance, the range of the 10 pre-calibrated k_lat values ​​is 0.2–1.0. For different intervals of the comprehensive risk coefficient, as the comprehensive risk coefficient increases, the corresponding k_lat value becomes larger.

[0108] After determining the torque compensation coefficient, the roll torque compensation value ΔF_lat can be determined based on the torque compensation coefficient and the vehicle's lateral acceleration using the following formula: ΔF_lat = k_lat × |a_y|, where a_y is the vehicle's current lateral acceleration and |a_y| is the absolute value of a_y.

[0109] After determining the roll moment compensation value, the front axle moment compensation value ΔF_lat_f and the rear axle moment compensation value ΔF_lat_r can be determined based on the following formulas: ΔF_lat_f = k_f × ΔF_lat ×m, ΔF_lat_r = k_r ×ΔF_lat ×m, k_f = (L - a) / L; k_r = a / L, where m is the total vehicle mass.

[0110] In some embodiments, assuming the vehicle is turning left (a_y>0) and the right wheel is the outer wheel, after determining the front axle torque compensation value, the braking force F_fl of the left front wheel and the braking force F_fr of the right front wheel can be determined based on the following algorithm: F_fl = F_f / 2 - ΔF_lat_f, F_fr = F_f / 2 + ΔF_lat_f; after determining the rear axle torque compensation value, the braking force F_rl of the left rear wheel and the braking force F_rr of the right rear wheel can be determined based on the following algorithm: F_rl = F_r / 2 - ΔF_lat_r, F_rr = F_r / 2 + ΔF_lat_r.

[0111] In some embodiments, after determining the target braking force (F_fl, F_fr, F_rl, F_rr) for each wheel, the brake-by-wire controller uses the target braking force of each wheel as the tracking target, and combines the actual braking state of the wheel end with real-time feedback to perform closed-loop braking force adjustment in order to achieve vehicle braking.

[0112] In some embodiments, if the overall risk coefficient does not meet the preset risk benchmark or the vehicle is not in the preset braking condition, the original strategy can be used to control the vehicle. For example, if the overall risk coefficient does not meet the preset risk benchmark and the vehicle is in the preset braking condition, the original braking strategy is used to perform vehicle braking (e.g., electro-hydraulic torque conversion is not performed, and vehicle braking is performed based on electro-regenerative torque).

[0113] The aforementioned vehicle braking control method establishes a comprehensive risk coefficient—a quantitative indicator that comprehensively reflects the vehicle's steering risk—based on multiple factors including steering wheel angle, steering angular velocity, vehicle speed, and road surface adhesion coefficient. This comprehensive risk coefficient is used to determine whether to execute electro-hydraulic torque conversion, upgrading it from passively responding to braking requests to actively predicting steering instability trends. This improves vehicle driving safety. Furthermore, by performing electro-hydraulic torque conversion under high-risk steering conditions, switching the single-axle electro-regenerative torque distribution to front-rear hydraulic braking torque distribution, the impact of single-axle electro-regenerative braking on vehicle yaw stability under high-risk steering conditions can be avoided, thereby improving lateral stability and reducing the likelihood of understeer or fishtailing. The electro-hydraulic torque conversion also suppresses understeer. The possibility of fishtailing makes the vehicle stability control system less likely to activate, reducing the frequency of intervention and thus decreasing the cumulative activation time of the system throughout the vehicle's lifespan. This reduces the likelihood of large yaw rate overshoot and helps suppress it. Furthermore, the distribution ratio of hydraulic braking torque between the front and rear axles can be adjusted based on a comprehensive risk factor, further enhancing lateral stability. This is applicable to different braking system types, allowing for different hydraulic braking torque distribution adjustment strategies. The resulting higher yaw control precision further ensures vehicle stability and safety. Moreover, by dynamically adjusting the front and rear axle hydraulic braking torque distribution ratio, the frequency of intervention by the vehicle stability control system can be further reduced.

[0114] like Figure 5 As shown, this application embodiment also provides a vehicle braking control device 40, which can be integrated into a vehicle. The vehicle braking control device 40 may include: The first determining module 401 is used to obtain the vehicle speed and / or the road surface adhesion coefficient of the road on which the vehicle travels, and to determine the vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient.

[0115] The second determining module 402 is used to obtain the steering wheel angle and steering angular velocity of the vehicle, and to determine the steering intention risk coefficient based on the steering wheel angle and steering angular velocity.

[0116] The third determining module 403 is used to determine the comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient.

[0117] The braking control module 404 is used to perform vehicle braking by adopting a first braking strategy or a second braking strategy if the comprehensive risk coefficient meets the preset risk benchmark and the vehicle is in a preset braking condition.

[0118] In some embodiments, a first braking strategy may include: performing an electro-hydraulic torque conversion operation to determine a target electro-regenerative torque and a target hydraulic braking torque, and performing vehicle braking based on the target electro-regenerative torque and the target hydraulic braking torque. The electro-hydraulic torque conversion operation may include gradually decreasing the electro-regenerative torque and gradually increasing the hydraulic braking torque according to preset rules, while maintaining the sum of the electro-regenerative torque and the hydraulic braking torque equal to the total braking torque. The total braking torque is determined based on a target braking deceleration corresponding to a preset braking condition. The preset rules include determining the target hydraulic braking torque based on the total braking torque and a preset function. The target electro-regenerative torque is determined based on the target hydraulic braking torque and the total braking torque. The preset function includes a time independent variable and a calibration constant corresponding to a comprehensive risk coefficient. A second braking strategy may include: obtaining the type of braking system in effect for the vehicle, and determining a braking force distribution strategy based on the braking system type; distributing the total braking force based on the braking force distribution strategy, and performing vehicle braking based on the braking force distribution result. The total braking force is determined based on a target braking deceleration corresponding to a preset braking condition. The braking force distribution strategy includes adjusting the braking force distribution ratio between the front axle and the rear axle based on a comprehensive risk coefficient.

[0119] The aforementioned modules can be programmable software instructions stored in memory and executable by the controller. It is understood that in other embodiments, the aforementioned modules can also be program instructions or firmware embedded in the controller.

[0120] Please refer to Figure 6 , Figure 6 This is a schematic diagram of one embodiment of the vehicle described in this application.

[0121] Vehicle 100 may include a memory 1010, a controller 1020, and a computer program 1030 stored in the memory 1010 and executable on the controller 1020. When the controller 1020 executes the computer program 1030, it implements the steps described in the vehicle braking control method embodiments above, for example... Figure 2 , Figure 3 , Figure 4 The steps are shown.

[0122] For example, the computer program 1030 can also be divided into one or more modules / units, one or more of which are stored in the memory 1010 and executed by the controller 1020. The one or more modules / units can be a series of computer program instruction segments capable of performing specific functions, and the instruction segments are used to describe the execution process of the computer program 1030 in the vehicle 100.

[0123] Those skilled in the art will understand that the schematic diagram is merely an example of vehicle 100 and does not constitute a limitation on vehicle 100. It may include more or fewer components than shown, or combine certain components, or different components. For example, vehicle 100 may also include… Figure 1 The sensor module 101 and vehicle braking system 102 shown are examples of such devices.

[0124] The controller 1020 can reuse the control chip originally deployed in the vehicle. The controller 1020 can be a microprocessor, electronic control unit, digital signal processor (DSP), application specific integrated circuit (ASIC), field-programmable gate array (FPGA), or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, etc.

[0125] The memory 1010 can be used to store computer programs 1030 and / or modules / units. The controller 1020 implements various functions of the vehicle 100 by running or executing the computer programs and / or modules / units stored in the memory 1010 and by calling data stored in the memory 1010. The memory 1010 may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, RAM, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other non-volatile solid-state storage device.

[0126] If the modules / units integrated in vehicle 100 are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a controller, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0127] This embodiment also provides a computer-readable storage medium storing computer instructions. When the computer instructions are executed on the controller, the controller performs the aforementioned method steps to implement the vehicle braking control method in the above embodiment.

[0128] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A vehicle braking control method, characterized in that, The method includes: Obtain the vehicle speed and / or the road surface adhesion coefficient of the road on which the vehicle travels, and determine the vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient. The steering wheel angle and steering angular velocity of the vehicle are obtained, and a steering intention risk coefficient is determined based on the steering wheel angle and steering angular velocity. Based on the vehicle driving risk coefficient and the steering intention risk coefficient, a comprehensive risk coefficient is determined; If the comprehensive risk coefficient meets the preset risk benchmark and the vehicle is in a preset braking condition, the first braking strategy or the second braking strategy shall be used to perform vehicle braking. The first braking strategy includes: performing an electro-hydraulic torque conversion operation to determine a target electro-regenerative torque and a target hydraulic braking torque, and performing vehicle braking based on the target electro-regenerative torque and the target hydraulic braking torque. The electro-hydraulic torque conversion operation includes gradually decreasing the electro-regenerative torque and gradually increasing the hydraulic braking torque according to a preset rule, while maintaining the sum of the electro-regenerative torque and the hydraulic braking torque equal to the total braking torque. The total braking torque is determined based on the target braking deceleration corresponding to the preset braking condition. The preset rule includes determining the target hydraulic braking torque based on the total braking torque and a preset function. The target electro-regenerative torque is determined based on the target hydraulic braking torque and the total braking torque. The preset function includes a time independent variable and a calibration constant corresponding to the comprehensive risk coefficient. The second braking strategy includes: obtaining the type of braking system that is effective for the vehicle, determining a braking force distribution strategy based on the braking system type, distributing the total braking force based on the braking force distribution strategy, and performing vehicle braking based on the braking force distribution result. The total braking force is determined based on the target braking deceleration corresponding to the preset braking condition. The braking force distribution strategy includes adjusting the braking force distribution ratio between the front axle and the rear axle based on the comprehensive risk coefficient.

2. The vehicle braking control method according to claim 1, characterized in that, The determination of the vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient includes: Based on the vehicle speed range and the road surface adhesion coefficient range, a first mapping table is queried to determine the vehicle driving risk coefficient. The first mapping table includes the mapping relationship between the combination of the vehicle speed range and the road surface adhesion coefficient range and the vehicle driving risk coefficient. The determination of the steering intention risk coefficient based on the steering wheel angle and steering angular velocity includes: Based on the steering wheel angle range to which the steering wheel angle belongs and the steering angular velocity range to which the steering angular velocity belongs, a second mapping table is consulted to determine the steering intention risk coefficient. The second mapping table includes the mapping relationship between the combination of the steering wheel angle range and the steering angular velocity range and the steering intention risk coefficient.

3. The vehicle braking control method according to claim 1, characterized in that, The determination of the comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient includes: The vehicle driving risk coefficient and the steering intention risk coefficient are input into a preset nonlinear function to determine the comprehensive risk coefficient. The preset nonlinear function has the characteristic that the output changes abruptly after the input increases to a threshold.

4. The vehicle braking control method according to claim 1, characterized in that, Determining the target hydraulic braking torque includes: The target hydraulic braking torque is determined based on the following formula: T_hyd(t) = T_total × (1 - ), where T_hyd(t) is the target hydraulic braking torque, T_total is the total braking torque, and t is the time variable. The calibration constant is defined as such, and different calibration constants correspond to different interval sizes of the comprehensive risk coefficient.

5. The vehicle braking control method according to claim 1, characterized in that, The effective braking system type is Electronic Stability Control (ESC) mode braking, and the distribution of total braking force based on the braking force distribution strategy includes: The front and rear axle reference braking force ratio is calculated based on the braking I curve and the longitudinal acceleration of the vehicle. Determine the dynamic allocation coefficient corresponding to the comprehensive risk coefficient; The actual braking force ratio between the front and rear axles is determined based on the aforementioned front and rear axle reference braking force ratio and the aforementioned dynamic distribution coefficient. Based on the total braking force and the actual braking force ratio between the front and rear axles, the braking force of the front axle and the braking force of the rear axle are determined.

6. The vehicle braking control method according to claim 1, characterized in that, The effective braking system type is brake-by-wire, and the total braking force is distributed based on the braking force distribution strategy: The front and rear axle reference braking force ratio is calculated based on the braking I curve and the longitudinal acceleration of the vehicle. Determine the dynamic allocation coefficient corresponding to the comprehensive risk coefficient; The actual braking force ratio between the front and rear axles is determined based on the aforementioned front and rear axle reference braking force ratio and the aforementioned dynamic distribution coefficient. Based on the total braking force and the actual braking force ratio between the front and rear axles, the front axle braking force and the rear axle braking force are determined. Determine the torque compensation coefficient corresponding to the comprehensive risk coefficient, and determine the roll torque compensation value based on the torque compensation coefficient and the lateral acceleration of the vehicle; Based on the roll moment compensation value and the vehicle's mass and wheelbase parameters, the front axle moment compensation value and the rear axle moment compensation value are determined. Based on the front axle torque compensation value and the front axle braking force, the braking force of the left front wheel and the braking force of the right front wheel are determined. Based on the rear axle torque compensation value and the rear axle braking force, the braking force of the left rear wheel and the braking force of the right rear wheel are determined.

7. A vehicle braking control method, characterized in that, The method includes: Obtain the vehicle speed and / or the road surface adhesion coefficient of the road on which the vehicle travels, and determine the vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient. The steering wheel angle and steering angular velocity of the vehicle are obtained, and a steering intention risk coefficient is determined based on the steering wheel angle and steering angular velocity. Based on the vehicle driving risk coefficient and the steering intention risk coefficient, a comprehensive risk coefficient is determined; If the comprehensive risk coefficient meets the preset risk benchmark and the vehicle is in a preset braking condition, the first braking strategy and the second braking strategy are used to perform vehicle braking. The first braking strategy includes: performing an electro-hydraulic torque conversion operation to determine a target electro-regenerative torque and a target hydraulic braking torque. The electro-hydraulic torque conversion operation includes gradually decreasing the electro-regenerative torque and gradually increasing the hydraulic braking torque according to a preset rule, while maintaining the sum of the electro-regenerative torque and the hydraulic braking torque equal to the total braking torque. The total braking torque is determined based on the target braking deceleration corresponding to the preset braking condition. The preset rule includes determining the target hydraulic braking torque based on the total braking torque and a preset function. The target electro-regenerative torque is determined based on the target hydraulic braking torque and the total braking torque. The preset function includes a time independent variable and a calibration constant corresponding to the comprehensive risk coefficient. The second braking strategy includes: obtaining the type of braking system that is effective for the vehicle; determining a braking torque distribution strategy based on the braking system type; distributing the hydraulic braking torque based on the braking torque distribution strategy; and performing vehicle braking based on the braking torque distribution result. The braking torque distribution strategy includes adjusting the braking torque distribution ratio between the front axle and the rear axle based on the comprehensive risk coefficient.

8. A vehicle braking control device, characterized in that, The device includes: The first determining module is used to obtain the vehicle speed and / or the road surface adhesion coefficient of the road on which the vehicle travels, and to determine the vehicle driving risk coefficient based on the vehicle speed and / or the road surface adhesion coefficient. The second determining module is used to obtain the steering wheel angle and steering angular velocity of the vehicle, and to determine the steering intention risk coefficient based on the steering wheel angle and steering angular velocity; The third determining module is used to determine a comprehensive risk coefficient based on the vehicle driving risk coefficient and the steering intention risk coefficient; The braking control module is used to perform vehicle braking by adopting a first braking strategy or a second braking strategy if the comprehensive risk coefficient meets the preset risk benchmark and the vehicle is in a preset braking condition. The first braking strategy includes: performing an electro-hydraulic torque conversion operation to determine a target electro-regenerative torque and a target hydraulic braking torque, and performing vehicle braking based on the target electro-regenerative torque and the target hydraulic braking torque. The electro-hydraulic torque conversion operation includes gradually decreasing the electro-regenerative torque and gradually increasing the hydraulic braking torque according to a preset rule, while maintaining the sum of the electro-regenerative torque and the hydraulic braking torque equal to the total braking torque. The total braking torque is determined based on the target braking deceleration corresponding to the preset braking condition. The preset rule includes determining the target hydraulic braking torque based on the total braking torque and a preset function. The target electro-regenerative torque is determined based on the target hydraulic braking torque and the total braking torque. The preset function includes a time independent variable and a calibration constant corresponding to the comprehensive risk coefficient. The second braking strategy includes: obtaining the type of braking system that is effective for the vehicle, determining a braking force distribution strategy based on the braking system type, distributing the total braking force based on the braking force distribution strategy, and performing vehicle braking based on the braking force distribution result. The total braking force is determined based on the target braking deceleration corresponding to the preset braking condition. The braking force distribution strategy includes adjusting the braking force distribution ratio between the front axle and the rear axle based on the comprehensive risk coefficient.

9. A vehicle, the vehicle comprising a vehicle braking system, a controller, and a memory, characterized in that, The memory is used to store instructions, and the controller is used to call the instructions in the memory to execute the vehicle braking control method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed on the controller, cause the controller to perform the vehicle braking control method as described in any one of claims 1 to 7.

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