Vehicle braking control method and system and vehicle

Abstract

The invention discloses a vehicle braking control method and system and a vehicle, and the method comprises the steps: when a parking instruction signal is received and the vehicle is in a parking state, obtaining a road adhesion coefficient of a vehicle driving road, a slope angle and mass of the vehicle, and a confidence coefficient corresponding to the road adhesion coefficient; the target parking force of the vehicle is determined according to the road adhesion coefficient, the slope angle, the mass and the confidence coefficient corresponding to the road adhesion coefficient, and a braking control instruction is generated; and controlling the vehicle to brake according to the braking control instruction, so that the parking force of the vehicle reaches the target parking force, and the braking and parking functions of the vehicle are realized. According to the method, the target parking force can be accurately and reasonably determined, excessive performance and resource mismatching caused by the too large parking force are avoided, meanwhile, unnecessary stress borne by a braking component is reduced, the service life of the braking component is prolonged, the maintenance cost is reduced, the work amount needed by an air compressor for overcoming spring force during parking braking releasing is reduced, and the service life of the air compressor is prolonged. And the energy cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, in particular to a brake control method and system of a vehicle and the vehicle. BACKGROUND

[0002] In the field of vehicle technology, especially in the field of commercial vehicles, the existing parking brake system mainly relies on the traditional spring energy storage parking brake system directly controlled by the hand-controlled parking brake valve. This parking method applies a single and usually maximum parking force determined by the physical properties of the spring regardless of the actual working conditions of the vehicle (such as empty flat ground, light load on a gentle slope, or full load on a steep slope).

[0003] However, in most parking scenarios, the required braking force of the vehicle is small, and the use of the existing active method will cause performance overkill and resource mismatch problems, and long-term excessive force will cause the braking components to bear huge mechanical stress, accelerate fatigue and wear and deformation, shorten the service life, increase maintenance costs, and at the same time, when releasing the parking brake, the air compressor needs to generate high pressure to overcome the spring force, and the maximum parking force will cause large single and long-term work, increasing energy costs. SUMMARY

[0004] The present application aims to at least solve one of the technical problems existing in the prior art.

[0005] To this end, one object of the present application is to propose a brake control method for a vehicle, which can accurately and reasonably determine the target parking force, avoid performance overkill and resource mismatch caused by excessive parking force, reduce unnecessary stress on the braking components, prolong the service life of the braking components, reduce maintenance costs, and reduce the work required by the air compressor to overcome the spring force when releasing the parking brake, thereby reducing energy costs.

[0006] To this end, a second object of the present application is to propose a brake control system for a vehicle.

[0007] To this end, a third object of the present application is to propose a vehicle.

[0008] To this end, a fourth object of the present application is to propose a computer-readable storage medium.

[0009] In order to achieve the above-mentioned purpose, an embodiment of the first aspect of the present invention proposes a vehicle braking control method, which includes: when a parking command signal is received and the vehicle is in a parking state, obtaining the road adhesion coefficient of the vehicle's driving road, the slope angle of the vehicle, the mass, and the confidence level corresponding to the road adhesion coefficient; determining the target parking force of the vehicle based on the road adhesion coefficient, the slope angle, the mass, and the confidence level corresponding to the road adhesion coefficient, and generating a braking control command based on the target parking force; controlling the braking of the vehicle based on the braking control command so that the parking force of the vehicle reaches the target parking force, thereby realizing the braking parking function of the vehicle.

[0010] According to the vehicle braking control method of an embodiment of the present invention, the target parking force of the vehicle is determined according to the road adhesion coefficient, slope angle, mass and the confidence level corresponding to the road adhesion coefficient, and the vehicle braking is controlled according to the target parking force. This allows for precise and reasonable application of appropriate braking force in different scenarios to avoid excess performance and resource mismatch caused by excessive parking force. At the same time, it can avoid accelerated fatigue wear and deformation of brake components caused by long-term exposure to excessive mechanical stress, thereby reducing unnecessary stress on brake components, extending the service life of brake components, and reducing maintenance costs. At the same time, it can reduce the amount of work required for the air compressor to overcome the spring force when releasing the parking brake, thereby reducing energy costs.

[0011] In addition, the vehicle braking control method according to the embodiment of the present invention may also have the following additional technical features: In some examples, obtaining the road adhesion coefficient of the vehicle's driving road, the vehicle's slope angle, mass, and the confidence level corresponding to the road adhesion coefficient includes: obtaining the vehicle's longitudinal slope angle, lateral slope angle, axle load data, air suspension pressure data, engine torque data, acceleration data, gear, wheel speed data, and yaw rate data; determining the vehicle's slope angle based on the longitudinal slope angle and the lateral slope angle; determining the vehicle's mass based on the vehicle's axle load data and the air suspension pressure data, or determining the vehicle's mass based on the engine torque data, the acceleration data, and the gear; determining the road adhesion coefficient and the confidence level corresponding to the road adhesion coefficient based on the wheel speed data, the acceleration data, and the yaw rate data.

[0012] In some examples, determining the target parking force of the vehicle based on the road adhesion coefficient, the slope angle, the mass, and the confidence level corresponding to the road adhesion coefficient includes: determining the dynamic adaptive safety factor based on the road adhesion coefficient and the confidence level corresponding to the road adhesion coefficient, querying the mapping relationship between a pre-calibrated road adhesion coefficient, the confidence level corresponding to the road adhesion coefficient, and the dynamic adaptive safety factor of the vehicle; determining the road adhesion angle based on the dynamic adaptive safety factor; and determining the target parking force of the vehicle based on the dynamic adaptive safety factor, the road adhesion angle, the slope angle, and the mass.

[0013] In some examples, generating a braking control instruction based on the target parking force includes: obtaining a target reverse control force corresponding to the target parking force based on a preset characteristic curve, wherein the characteristic curve is obtained based on a mapping relationship between the target parking force and the target reverse control force; and generating the braking control instruction based on the target reverse control force.

[0014] In some examples, the vehicle includes a spring energy storage brake cylinder and at least one high-precision air pressure regulating valve, and the braking of the vehicle is controlled according to the braking control instruction so that the parking force of the vehicle reaches the target parking force, including: controlling the high-precision air pressure regulating valve to adjust the air pressure in the spring chamber of the spring energy storage brake cylinder according to the braking control instruction so that the pressure in the spring chamber reaches the target reverse control pressure, thereby making the parking force of the vehicle reach the target parking force. In some examples, after controlling the braking of the vehicle according to the braking control instruction, it also includes: obtaining the air pressure in the spring chamber of the spring energy storage brake cylinder and the ambient temperature of the vehicle in real time; determining the target pressure change according to the target reverse control force and the air pressure in the spring chamber of the spring energy storage brake cylinder; determining a first control instruction for controlling the braking of the vehicle according to the ambient temperature and the target pressure change; determining a second control instruction for controlling the braking of the vehicle according to the target pressure change; and adjusting the braking state of the vehicle according to the first control instruction and the second control instruction so that the difference between the pressure in the spring chamber and the target reverse control pressure is within a preset difference range.

[0015] In some examples, the brake control method of the vehicle further includes: calibrating the preset characteristic curve when the vehicle meets a calibration condition; wherein the calibration condition includes: the vehicle being in a parking state and the vehicle having traveled a preset mileage threshold and / or the vehicle having started a preset number of times; or receiving a user-issued active calibration instruction; or the pressure in the spring chamber of the spring-accumulating brake master cylinder deviating from a preset pressure by more than a preset deviation threshold for a preset time.

[0016] In some examples, the calibration of the preset characteristic curve includes: controlling the high-precision air pressure regulating valve to adjust the pressure in the spring chamber of the spring-accumulating brake master cylinder to zero, and obtaining the maximum physical force of the spring-accumulating brake master cylinder; and proportionally scaling or nonlinearly correcting the preset characteristic curve according to the difference between the maximum physical force and a preset maximum physical force to calibrate the preset characteristic curve.

[0017] In some examples, the brake control method of the vehicle further includes: when the vehicle fails, determining a corresponding failure level according to failure information, and triggering a corresponding failure handling strategy according to the failure level; wherein the failure level includes: a first failure, a second failure, and a third failure; when the failure level is the first failure, the corresponding failure handling strategy is to make the pressure in the spring chamber zero to make the spring-accumulating brake master cylinder output the maximum physical force; when the failure level is the second failure, the corresponding failure handling strategy is to make the brake control method of the vehicle switch to a preset conservative force mode, wherein the preset conservative force mode is a mode in which the spring-accumulating brake master cylinder outputs a preset physical force; and when the failure level is the third failure, the corresponding failure handling strategy is to make the brake control system of the vehicle dynamically increase a safety margin.

[0018] In some examples, the brake control method of the vehicle further includes: displaying the failure level through a user interface, and displaying corresponding failure alarm information according to the failure level.

[0019] In order to achieve the above object, the embodiment of the second aspect of the present application provides a brake control system of a vehicle, comprising: a sensing unit configured to acquire a road surface adhesion coefficient of a road on which the vehicle travels, a slope angle of the vehicle, a mass of the vehicle and a confidence degree corresponding to the road surface adhesion coefficient when a parking instruction signal is received and the vehicle is in a parking state; a determining unit configured to determine a target parking force of the vehicle according to the road surface adhesion coefficient, the slope angle, the mass and the confidence degree corresponding to the road surface adhesion coefficient, and generate a brake control instruction according to the target parking force; and a control unit configured to control the vehicle to brake according to the brake control instruction, so that the parking force of the vehicle reaches the target parking force, and the brake parking function of the vehicle is realized.

[0020] According to the brake control system of the vehicle, the target parking force of the vehicle is determined according to the road surface adhesion coefficient, the slope angle, the mass and the confidence degree corresponding to the road surface adhesion coefficient, and the vehicle is controlled to brake according to the target parking force, so that appropriate brake force can be accurately and reasonably applied in different scenes, performance excess and resource mismatch caused by excessive parking force can be avoided, meanwhile, accelerated fatigue wear and deformation of brake components caused by long-term bearing of excessive mechanical stress can be avoided, so that unnecessary stress borne by the brake components is reduced, the service life of the brake components is prolonged, maintenance cost is reduced, meanwhile, the work amount required for the air compressor to overcome the spring force when the parking brake is released is reduced, and energy cost is further reduced.

[0021] In order to achieve the above object, the embodiment of the third aspect of the present application discloses a vehicle, comprising: the brake control system of the vehicle according to the embodiment of the second aspect of the present application; or a processor, a memory, and a brake control program of the vehicle stored in the memory and executable on the processor, when the brake control program of the vehicle is executed by the processor, the brake control method of the vehicle according to the embodiment of the first aspect of the present application is realized.

[0022] According to the vehicle, the target parking force of the vehicle is determined according to the road surface adhesion coefficient, the slope angle, the mass and the confidence degree corresponding to the road surface adhesion coefficient, and the vehicle is controlled to brake according to the target parking force, so that appropriate brake force can be accurately and reasonably applied in different scenes, performance excess and resource mismatch caused by excessive parking force can be avoided, meanwhile, accelerated fatigue wear and deformation of brake components caused by long-term bearing of excessive mechanical stress can be avoided, so that unnecessary stress borne by the brake components is reduced, the service life of the brake components is prolonged, maintenance cost is reduced, meanwhile, the work amount required for the air compressor to overcome the spring force when the parking brake is released is reduced, and energy cost is further reduced.

[0023] To achieve the above object, the fourth aspect of the present application discloses a computer readable storage medium, wherein the computer readable storage medium stores a vehicle braking control program, and the vehicle braking control program is executed by a processor to implement the vehicle braking control method according to the first aspect of the present application.

[0024] The computer readable storage medium according to the embodiment of the present application stores the vehicle braking control program, and the vehicle braking control program is executed by the processor to determine the target parking force of the vehicle according to the road adhesion coefficient, the slope angle, the mass and the confidence degree corresponding to the road adhesion coefficient, and control the vehicle braking according to the target parking force, so that appropriate braking force can be accurately and reasonably applied in different scenes, the performance overkill and resource mismatch caused by excessive parking force can be avoided, the accelerated fatigue wear and deformation of the braking components caused by long-term bearing of excessive mechanical stress can be avoided, the unnecessary stress borne by the braking components can be reduced, the service life of the braking components can be prolonged, the maintenance cost can be reduced, the work amount required for the air compressor to overcome the spring force when releasing the parking brake can be reduced, and the energy cost can be reduced.

[0025] Additional aspects and advantages of the present application will be made apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0026] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, taken in conjunction with the accompanying drawings, in which: Figure 1 is a flowchart of a vehicle braking control method according to an embodiment of the present application; Figure 2 is a structural diagram of a vehicle braking control system according to an embodiment of the present application.

[0027] REFERENCE NUMERALS Vehicle braking control system - 100; perception unit - 110; determination unit - 120; control unit - 130. DETAILED DESCRIPTION

[0028] In order to enable persons skilled in the art to more fully understand the features and technical contents of the embodiments of the present application, the implementation of the embodiments of the present application is described in detail below with reference to the accompanying drawings, which are used for reference only and do not limit the embodiments of the present application. In the following technical description, in order to facilitate explanation, a plurality of details are provided to provide a full understanding of the disclosed embodiments. However, one or more embodiments can still be implemented without these details. In other cases, well-known structures and devices can be simplified to facilitate the drawings.

[0029] The following description will be made with reference to the drawingsFigures 1-2 A method and system for controlling braking of a vehicle are described.

[0030] Figure 1 is a flowchart of a method for controlling braking of a vehicle according to an embodiment of the present application, as shown, the method comprises the following steps: Figure 1 Upon receiving a parking instruction signal and the vehicle being in a parking state, a road surface adhesion coefficient of a road on which the vehicle travels, a slope angle of the vehicle, a mass of the vehicle, and a confidence level corresponding to the road surface adhesion coefficient are obtained.

[0031] Specifically, upon receiving a parking instruction signal and the vehicle being in a parking state, i.e., receiving a parking signal triggered by the driver pulling a handle or pressing an electronic switch, and detecting that the vehicle speed obtained by the vehicle speed sensor approaches zero, the road surface adhesion coefficient of the road on which the vehicle travels, the slope angle of the vehicle, the mass of the vehicle, and the confidence level corresponding to the road surface adhesion coefficient can be obtained. The road surface adhesion coefficient includes but is not limited to being obtained by a road surface adhesion coefficient estimation module provided in the vehicle, which is generally integrated in an electronic control braking system or an anti-lock braking system electronic control unit. The road surface adhesion coefficient can be estimated in real time based on information such as wheel speed, vehicle acceleration, yaw rate, etc. by a specific algorithm (such as based on slip rate analysis, Kalman filtering, etc.), and the confidence level corresponding to the road surface adhesion coefficient is output. The slope angle of the vehicle refers to the degree of inclination of the road on which the vehicle travels, which includes but is not limited to being obtained by an inertial measurement unit provided in the vehicle, which can provide real-time attitude information such as vehicle longitudinal slope angle and lateral slope angle, and determine the slope angle of the road on which the vehicle is located based on the above information. The mass of the vehicle includes but is not limited to being obtained by a vehicle total mass estimation module provided in the vehicle, which can estimate the mass of the vehicle based on axle load sensor data of the electronic control braking system, air suspension pressure sensor data, or estimate the mass of the vehicle based on engine torque, acceleration, gear position, etc.

[0032] The target parking force of the vehicle is determined based on the road surface adhesion coefficient, the slope angle, the mass, and the confidence level corresponding to the road surface adhesion coefficient, and a braking control instruction is generated based on the target parking force.

[0033] Specifically, after determining the road surface adhesion coefficient, the slope angle, the mass, and the confidence level corresponding to the road surface adhesion coefficient, the electronic control braking system of the vehicle can receive the above data and perform calculations based on an algorithm preset in the electronic control braking system of the vehicle to determine the target parking force of the vehicle based on the road surface adhesion coefficient, the slope angle, the mass, and the confidence level corresponding to the road surface adhesion coefficient. At the same time, a corresponding braking control instruction can be generated based on the target parking force.

[0034] ​According to the brake control instruction, the vehicle is controlled to brake, so that the parking force of the vehicle reaches the target parking force, and the brake parking function of the vehicle is realized.

[0035] Specifically, after the target parking force is calculated by the preset algorithm and the brake control instruction is generated, the brake execution system of the vehicle can receive the brake control instruction to control the vehicle to brake, so that the parking force of the vehicle reaches the target parking force, and the brake parking function of the vehicle is realized. The brake execution system of the vehicle includes but is not limited to a related control module in an electronic control brake system and an execution unit such as a high-precision air pressure regulating valve and a spring energy storage brake sub-pump.

[0036] Therefore, the above-mentioned vehicle brake control method determines the target parking force of the vehicle according to the road adhesion coefficient, the slope angle, the mass and the confidence degree corresponding to the road adhesion coefficient, controls the vehicle brake according to the target parking force, can accurately and reasonably apply appropriate brake force in different scenes, avoids performance overkill and resource mismatch caused by excessive parking force, can avoid accelerated fatigue wear and deformation of brake components caused by long-term bearing of excessive mechanical stress, thereby reducing unnecessary stress borne by the brake components, prolonging the service life of the brake components, reducing maintenance costs, and reducing the work amount required for the air pressure machine to overcome the spring force when releasing the parking brake, thereby reducing energy costs.

[0037] In an embodiment of the present application, the road adhesion coefficient of the road on which the vehicle travels, the slope angle of the vehicle, the mass of the vehicle and the confidence degree corresponding to the road adhesion coefficient are obtained, including: obtaining the longitudinal slope angle, the transverse slope angle, the axle load data, the air suspension pressure data, the engine torque data, the acceleration data, the gear, the wheel speed data and the yaw rate data of the vehicle; The slope angle of the vehicle is determined according to the longitudinal slope angle and the transverse slope angle; The mass of the vehicle is determined according to the axle load data and the air suspension pressure data of the vehicle, or the mass of the vehicle is determined according to the engine torque data, the acceleration data and the gear; The road adhesion coefficient and the confidence degree corresponding to the road adhesion coefficient are determined according to the wheel speed data, the acceleration data and the yaw rate data.

[0038] Specifically, when the slope angle of the vehicle is obtained, the longitudinal slope angle and the transverse slope angle of the vehicle can be directly measured by a high-precision dual-axis inclination sensor, and the slope angle of the vehicle is determined according to the longitudinal slope angle and the transverse slope angle, including but not limited to vector synthesis of the longitudinal slope angle and the transverse slope angle to obtain the slope angle describing the overall inclination of the road on which the vehicle travels.

[0039] Further, when the mass of the vehicle is acquired, the axle load data and the air suspension pressure data of the vehicle can be acquired, and the axle load data and the air suspension pressure data are comprehensively analyzed and calculated to determine the mass of the vehicle. For example, the mass of the vehicle can be calculated by using a pre-established mathematical model or algorithm according to the distribution of the axle load and the size of the air suspension pressure; or the engine torque data, the acceleration data, and the gear information can be acquired, and the mass of the vehicle is determined by using a dynamics principle algorithm. For example, the mass of the vehicle can be calculated according to Newton's second law, in combination with the driving force of the engine torque output, the transmission ratio corresponding to the gear, and the acceleration of the vehicle.

[0040] Further, when the road surface adhesion coefficient of the driving road of the vehicle and the confidence corresponding to the road surface adhesion coefficient are acquired, the wheel speed data, the acceleration data, and the yaw rate data of the vehicle can be acquired by the corresponding sensors in the vehicle, and the road surface adhesion coefficient and the confidence corresponding to the road surface adhesion coefficient can be determined based on a slip rate analysis, Kalman filtering, and the like.

[0041] In an embodiment of the present application, the target parking force of the vehicle is determined according to the road surface adhesion coefficient, the slope angle, the mass, and the confidence corresponding to the road surface adhesion coefficient, comprising: determining the dynamic adaptive safety coefficient according to the road surface adhesion coefficient and the confidence corresponding to the road surface adhesion coefficient by querying the mapping relationship between the pre-calibrated road surface adhesion coefficient, the confidence corresponding to the road surface adhesion coefficient, and the dynamic adaptive safety coefficient of the vehicle. determining the road surface adhesion angle according to the dynamic adaptive safety coefficient; determining the target parking force of the vehicle according to the dynamic adaptive safety coefficient, the road surface adhesion angle, the slope angle, and the mass.

[0042] Specifically, since the dynamic adaptive safety coefficient not only depends on the road surface adhesion coefficient, but also is closely related to the confidence corresponding to the road surface adhesion coefficient, in the process of determining the target parking force of the vehicle according to the road surface adhesion coefficient, the slope angle, the mass, and the confidence corresponding to the road surface adhesion coefficient, first, the dynamic adaptive safety coefficient of the vehicle can be determined according to the road surface adhesion coefficient and the confidence corresponding to the road surface adhesion coefficient. The determination manner includes but is not limited to querying the mapping relationship between the pre-calibrated road surface adhesion coefficient, the confidence corresponding to the road surface adhesion coefficient, and the dynamic adaptive safety coefficient of the vehicle according to the road surface adhesion coefficient and the confidence corresponding to the road surface adhesion coefficient, to determine the dynamic adaptive safety coefficient.

[0043] In a specific embodiment, when the confidence degree corresponding to the road adhesion coefficient reaches 0.7 (high confidence degree, such as dry asphalt road surface), the dynamic adaptive safety factor takes its base value, for example, between 0.15 and 0.25 according to different road adhesion coefficients, while when the confidence degree corresponding to the road adhesion coefficient linearly decreases from 0.7 to 0.2 (low confidence degree, such as complex ice-snow mixed road surface or unstable sensor signal), the dynamic adaptive safety factor can linearly increase from its base value corresponding to the road adhesion coefficient to a larger upper limit value, for example, 0.4.

[0044] Further, the road adhesion angle is determined according to the dynamic adaptive safety factor, and a specific formula is as follows: , wherein, represents the road adhesion angle, represents the dynamic adaptive safety factor.

[0045] Further, the target parking force of the vehicle can be determined according to the dynamic adaptive safety factor, the road adhesion angle, the slope angle and the mass, and a specific formula is as follows: , wherein: represents the acceleration of gravity, represents the road adhesion angle, represents the dynamic adaptive safety factor, represents the slope angle, represents the mass.

[0046] In an embodiment of the present application, the brake control instruction is generated according to the target parking force, including: obtaining the target reverse control force corresponding to the target parking force according to a preset characteristic curve, wherein the characteristic curve is obtained based on the mapping relationship between the target parking force and the target reverse control force. The brake control instruction is generated according to the target reverse control force.

[0047] Specifically, in the brake system of the vehicle, since the output clamping force (i.e. parking force) of the spring energy storage brake master cylinder of the vehicle and the control pressure (i.e. reverse control pressure) in the spring chamber are generally in an approximately inverse nonlinear relationship, a large number of experiments and calibration work can be performed to obtain the target reverse control pressure (i.e. target reverse control force) in the spring chamber corresponding to different target parking forces, and the corresponding relationship is plotted into a characteristic curve, so that after the target parking force is determined, the target reverse control force corresponding to the target parking force can be obtained according to the preset characteristic curve.

[0048] Further, according to the obtained target reverse control force, a corresponding brake control instruction can be generated, which is usually in the form of an electrical signal and is sent to the execution component of the brake system of the vehicle, for example, by a pulse width modulation signal, wherein the duty cycle, frequency and duration of the pulse width modulation signal can be adjusted according to the size of the target reverse control force, so as to realize accurate control of the execution component of the brake system of the vehicle.

[0049] In an embodiment of the present application, the vehicle comprises a spring-energized brake caliper and at least one high-precision air pressure regulating valve, and the vehicle is controlled to brake according to a brake control instruction, so that the parking force of the vehicle reaches a target parking force, comprising: controlling the high-precision air pressure regulating valve to adjust the air pressure in the spring chamber of the spring-energized brake caliper according to the brake control instruction, so that the pressure in the spring chamber reaches a target reverse control pressure, thereby making the parking force of the vehicle reach the target parking force.

[0050] Specifically, the vehicle comprises a spring-energized brake caliper and at least one high-precision air pressure regulating valve arranged on the wheel or axle. For example, when the vehicle is controlled to brake according to a brake control instruction, the high-precision air pressure regulating valve can receive the brake control instruction, adjust the amount of air entering or exiting the spring chamber of the spring-energized brake caliper according to the brake control instruction, change the air pressure in the spring chamber, so that the pressure in the spring chamber reaches a target reverse control pressure, thereby making the parking force of the vehicle reach the target parking force.

[0051] In specific embodiments, the execution components such as the high-precision air pressure regulating valve are all selected from vehicle-grade products that meet the automotive industry standards (such as a working temperature range of -40℃ to +85℃ or higher, anti-vibration, anti-electromagnetic interference, etc.).

[0052] In an embodiment of the present application, after the vehicle is controlled to brake according to the brake control instruction, further comprising: acquiring the air pressure in the spring chamber of the spring-energized brake caliper and the ambient temperature of the vehicle in real time; determining a target pressure change amount according to the target reverse control force and the air pressure in the spring chamber of the spring-energized brake caliper; determining a first control instruction for controlling the vehicle to brake according to the ambient temperature and the target pressure change amount; determining a second control instruction for controlling the vehicle to brake according to the target pressure change amount; adjusting the braking state of the vehicle according to the first control instruction and the second control instruction, so that the difference between the pressure in the spring chamber and the target reverse control pressure is within a preset difference range.

[0053] Specifically, after controlling the vehicle to brake according to the brake control instruction, the air pressure in the spring chamber can be monitored in real time by a high-precision pressure sensor installed on the spring chamber air path, and the ambient temperature of the vehicle can be obtained in real time by a temperature sensor arranged in the vehicle.

[0054] Further, the target pressure change amount, i.e., the difference between the air pressure corresponding to the target reverse control force and the current air pressure in the spring chamber, can be determined according to the determined target reverse control force and the real-time obtained air pressure in the spring chamber of the spring energy storage brake master cylinder. For example, if the air pressure corresponding to the target reverse control force is , and the current air pressure in the spring chamber is , then the target pressure change amount .

[0055] Further, the first control instruction for controlling the vehicle to brake can be generated according to the ambient temperature and the target pressure change amount, combined with the pre-stored algorithm and model, wherein the first control instruction mainly considers the compensation effect of the ambient temperature on the air pressure adjustment, so as to ensure that the air pressure can be accurately adjusted in different temperature environments, so as to quickly overcome the mechanical and pneumatic inertia and hysteresis of the brake system of the vehicle.

[0056] Further, the second control instruction can be generated according to the target pressure change amount through the pre-stored algorithm and model.

[0057] Further, the brake state of the vehicle can be adjusted according to the first control instruction and the second control instruction, so that the difference between the pressure in the spring chamber and the target reverse control pressure is within a preset difference range. It can be understood that the first control instruction is a feedforward compensation instruction, and the second control instruction is a real-time feedback adjustment instruction. For example, after adjusting the brake state of the vehicle according to the first control instruction, the real-time monitored air pressure in the spring chamber by the pressure sensor can be received in real time, and the target pressure change amount can be determined in real time. The target pressure change amount is input to the PID (Proportional Integral Derivative) controller, so that the PID controller continuously adjusts the pulse control signal, so that the difference between the pressure in the spring chamber and the target reverse control pressure is within a preset difference range.

[0058] In specific embodiments, when adjusting the braking state of the vehicle, a state signal from the vehicle air handling unit, such as a state signal of the air dryer and an ambient humidity sensor, can also be received, and when the decline rate of the regeneration efficiency of the air dryer exceeds a preset decline rate threshold or the rise rate of the ambient humidity exceeds a preset rise rate threshold, the dynamic adaptive safety factor can be increased or the preset difference range can be narrowed to preventively counter the risk of valve response delay or jamming due to potential condensate icing in the air circuit.

[0059] In an embodiment of the present application, the braking control method of the vehicle further comprises: calibrating the preset characteristic curve when the vehicle meets a calibration condition; The calibration condition comprises that the vehicle is in the parking state and the vehicle mileage reaches a preset mileage threshold and / or the engine start-up times of the vehicle reaches a preset number threshold. Alternatively, a user-issued active calibration instruction is received. Alternatively, the time when the deviation of the air pressure in the spring chamber of the spring energy storage brake master cylinder from the preset pressure is greater than a preset deviation threshold reaches a preset time.

[0060] Specifically, as the vehicle is used, the spring and other components of the spring energy storage brake master cylinder may age, wear, and the like, causing the maximum physical force of the spring to change. At this time, if the preset characteristic curve is not calibrated, the accuracy of the target reverse control force calculated based on the original characteristic curve will gradually decrease, which may cause the parking force of the vehicle to fail to reach the target parking force, affecting parking safety. Therefore, the preset characteristic curve can be calibrated when the vehicle meets the calibration condition.

[0061] Further, when the vehicle is in the parking state and the vehicle mileage reaches a preset mileage threshold and / or the engine start-up times of the vehicle reaches a preset number threshold (e.g., 5000 kilometers of cumulative travel and / or 200 engine start-ups), it is determined that the calibration condition is met, and the preset characteristic curve can be calibrated. It can be understood that when the vehicle is in the parking state and the vehicle mileage reaches a preset mileage threshold, it indicates that the spring of the spring energy storage brake master cylinder may have aged significantly, and at this time the preset characteristic curve needs to be calibrated. When the engine start-up times reaches a preset number threshold, it indicates that the performance of the spring may have changed significantly, and at this time the preset characteristic curve also needs to be calibrated.

[0062] Furthermore, in some special scenarios, users can also judge the performance changes of the vehicle's parking system based on their own usage experience and actively calibrate it. For example, users can issue active calibration instructions through the vehicle's central control infotainment screen, dedicated diagnostic tools, etc. to calibrate the preset characteristic curve.

[0063] Furthermore, when the deviation between the air pressure in the spring chamber and the preset pressure is greater than the preset deviation threshold and lasts for a preset time, it indicates that the performance of the spring may have changed significantly, resulting in abnormal air pressure regulation. At this time, the calibration of the preset characteristic curve can be automatically triggered to ensure the accuracy of the air pressure regulation.

[0064] In a specific embodiment, the preset deviation threshold may be set to 0.5 bar, and the preset time may be set to 10 seconds, 30 seconds, or the like.

[0065] In one embodiment of the present invention, calibrating a preset characteristic curve includes: controlling a high-precision air pressure regulating valve to adjust the air pressure in a spring chamber of a spring energy storage brake cylinder so that the pressure in the spring chamber is zero, and obtaining a maximum physical force of the spring energy storage brake cylinder; The preset characteristic curve is scaled proportionally or nonlinearly corrected according to the difference between the maximum physical force and the preset maximum physical force, so as to calibrate the preset characteristic curve.

[0066] Specifically, when calibrating the preset characteristic curve, first, the high-precision air pressure regulating valve can be controlled to accurately control the intake and exhaust of the spring energy storage brake cylinder, and the spring chamber of the spring energy storage brake cylinder can be connected to the outside atmosphere, so that the gas in the spring chamber is gradually discharged to make the pressure in the spring chamber zero. At this time, the air pressure balance force disappears, the spring of the spring energy storage brake cylinder is completely released, and the spring can exert its current maximum physical force.

[0067] Furthermore, the maximum physical force of the spring at this time can be obtained in a variety of ways, including but not limited to estimating the data obtained by devices such as shaft end torque sensors or brake shoe clearance sensors to determine the maximum physical force of the spring, or testing on a standard test bench or road surface with a known slight slope (such as 1-2%) to observe whether the vehicle has a slight displacement, or how much reverse driving force is required to move it, thereby inferring the maximum physical force of the spring, or measuring some key parameters (such as motor current, if there is an auxiliary motor; or strain gauge readings of specific components, if any) and comparing them with the parameters during initial calibration to obtain the maximum physical force of the spring.

[0068] Further, the preset characteristic curve can be scaled proportionally or nonlinearly corrected according to the difference between the maximum physical force and the preset maximum physical force to calibrate the preset characteristic curve. For example, if the difference between the maximum physical force and the preset maximum physical force changes little, that is, the overall performance of the spring is linearly attenuated or enhanced, the characteristic curve can be calibrated by using the proportional scaling method. For example, a scaling factor can be calculated, and then each force value on the preset characteristic curve is multiplied by the scaling factor to obtain a new force value, so as to calibrate the preset characteristic curve. If the difference between the maximum physical force and the preset maximum physical force changes greatly, that is, the overall performance of the spring is nonlinearly attenuated or enhanced, the characteristic curve can be calibrated by using the nonlinear correction method. For example, the key inflection point parameters on the preset characteristic curve are adjusted, or the entire preset characteristic curve is nonlinearly fitted and corrected, so that the corrected characteristic curve more accurately reflects the actual performance of the current spring.

[0069] In an embodiment of the present application, the brake control method of the vehicle further comprises: when the vehicle fails, determining the corresponding failure level according to the failure information, and triggering the corresponding failure handling strategy according to the failure level; wherein the failure level includes: a first failure, a second failure and a third failure. When the failure level is the first failure, the corresponding failure handling strategy is to make the pressure in the spring chamber zero, so that the spring energy storage brake master cylinder outputs the maximum physical force. When the failure level is the second failure, the corresponding failure handling strategy is to switch the brake control method of the vehicle to a preset conservative force mode, wherein the preset conservative force mode is a mode in which the physical force output by the spring energy storage brake master cylinder is a preset physical force. When the failure level is the third failure, the corresponding failure handling strategy is to dynamically increase the safety margin of the brake control system of the vehicle.

[0070] Specifically, during the operation of the vehicle, whether the vehicle fails can be detected in real time, and when a failure occurs, the corresponding failure level can be determined according to the failure information, and the corresponding failure handling strategy can be triggered according to the failure level, wherein the failure level includes: a first failure, a second failure and a third failure.

[0071] Further, when the failure level is the first failure, the spring energy storage brake master cylinder can be connected to the atmosphere by controlling the high-precision air pressure regulating valve, so that the gas in the chamber is quickly discharged, so that the pressure in the chamber is quickly reduced to zero, so that the spring energy storage brake master cylinder outputs the maximum physical force. At this time, the safety of the vehicle is equivalent to or even higher than that of the traditional pure mechanical air control system.

[0072] Further, when the fault level is secondary fault, the vehicle can be controlled to switch to a preset conservative force mode, in which the spring energy storage brake master cylinder outputs a preset medium safety force that can ensure safe parking on a typical or regulatory required large slope (for example, based on the 18% slope in the standard regulations, or a specific slope calibrated according to the vehicle model and target market regulations), for example, the force is usually 70%-85% of the maximum physical force (this percentage can be calibrated before delivery according to the maximum design total weight of the vehicle model and the target market regulations), to ensure that the legal slope parking requirements of the vehicle model are met.

[0073] Further, when the fault level is tertiary fault, the safety margin of the vehicle's brake control system is dynamically increased, that is, without changing the working mode of the vehicle's adaptive control, but dynamically increasing the safety margin through internal algorithms, including but not limited to automatically and smoothly increasing the value of the dynamic adaptive safety coefficient according to the degree of confidence reduction, thereby indirectly increasing the target parking force, or enabling stronger digital filtering algorithms for input signals (such as slope, pressure feedback) to suppress noise, or slightly relaxing the response speed requirements of the PID controller, or increasing the allowed error threshold of the pressure control to adapt to slight performance degradation of the execution components.

[0074] In specific embodiments, when the vehicle's control system is completely powered off or the core microprocessor is severely malfunctioning (such as watchdog timeout unable to recover), or the electrical driving part of the high-precision air pressure regulating valve is completely failed (such as coil open circuit, driving chip damaged) and cannot execute any instructions, or the key control line (such as communication bus or pulse signal line) between the vehicle's control system and the high-precision air pressure regulating valve is completely interrupted, the fault level can be determined as primary fault; when the sensing unit signal acquiring the key data of the vehicle is lost for a long time or diagnosed as untrustworthy (for example: the slope sensor signal is continuously invalid, the vehicle total mass estimation module output is abnormal, the road adhesion coefficient estimation module has no valid output for a long time), or the pressure sensor reading is diagnosed as completely wrong (such as always being the maximum or minimum value, or being significantly inconsistent with the command pressure and unable to be corrected by calibration), or the high-precision air pressure regulating valve can respond but its regulation accuracy or response speed is diagnosed as significantly decreased (such as unable to stabilize near the target parking force, or the response time is much longer than expected), the fault level can be determined as secondary fault; when the road adhesion coefficient output by the road adhesion coefficient estimation module has a continuously low confidence (for example, lower than the preset threshold of 0.7 but higher than the threshold of complete failure of 0.2), or the slope sensor or pressure sensor signal has short-term, recoverable high-frequency noise or unstable fluctuations but has not reached the level of complete failure, or the response of the high-precision air pressure regulating valve is slightly delayed or has slight overshoot but can still basically complete the pressure regulation task, the fault level can be determined as tertiary fault.

[0075] In an embodiment of the present application, the brake control method of the vehicle further comprises: displaying the fault level through the user interface, and displaying corresponding fault alarm information according to the fault level.

[0076] Specifically, when the vehicle has a fault, the fault level can be displayed through the user interface, and corresponding fault alarm information can be displayed according to the fault level. For example, when the fault level is a first-level fault, a first-level fault identifier can be displayed through the user interface (such as a central control screen), a serious fault indicator light can be instructed to be turned on, a red icon can be displayed on the central control screen, and a sound alarm information can be issued to provide a serious warning prompt to remind the driver to stop and check immediately and seek professional maintenance; when the fault level is a second-level fault, a second-level fault identifier can be displayed through the user interface, a yellow icon can be displayed through the central control screen, and a warning information such as “the slope sensor signal is lost, the parking system has enabled the enhanced parking force mode, please drive carefully and repair as soon as possible” can be displayed; when the fault level is a third-level fault, a third-level fault identifier can be displayed through the user interface, an indirectly flashing yellow icon can be displayed through the central control screen, and a prompt information such as “the road condition is complex, the parking system has automatically adjusted the safety parameters” can be displayed.

[0077] In specific embodiments, the user interface can also display information such as “the intelligent parking system is running normally” on related pages such as “vehicle status” or “parking assist”, and can display a green icon indicating that the adaptive parking force control function is running normally, and the vehicle's brake control system is applying the best parking force according to real-time needs. At the same time, in the multi-functional display area of the instrument panel of some high-end vehicles, a simple dynamic bar chart or percentage value can also be displayed to indicate the approximate percentage of “current parking force / highest available physical force” in real time (for example, “parking force: 25%”), so as to enhance the driver's intuitive perception of the system's working state.

[0078] In summary, according to the brake control method of the vehicle in the embodiment of the present application, the target parking force of the vehicle is determined according to the road adhesion coefficient, the slope angle, the mass, and the confidence degree corresponding to the road adhesion coefficient, and the vehicle brake is controlled according to the target parking force, so that appropriate brake force can be accurately and reasonably applied in different scenes, performance overmatching and resource mismatching caused by excessive parking force can be avoided, at the same time, brake components can be prevented from accelerated fatigue wear and deformation caused by long-term bearing of excessive mechanical stress, so as to reduce unnecessary stress borne by the brake components, prolong the service life of the brake components, reduce maintenance cost, at the same time, the work amount required for the air compressor to overcome the spring force when releasing the parking brake can be reduced, and then the energy cost is reduced. Further, when the vehicle meets the calibration condition, the preset characteristic curve is calibrated, so that the aging and wear of the spring and other components of the spring energy storage brake master cylinder can be avoided, the maximum physical force of the spring changes, the accuracy of the target parking force is reduced, and the calculation accuracy of the target parking force is maintained. Further, through the intelligent fault grading safety strategy, more reasonable and more detailed risk management can be provided, the vehicle safety is improved to a new level, and the safety and reliability of the brake system of the vehicle are improved.

[0079] A further embodiment of the present application proposes a brake control system 100 of a vehicle, as shown in Figure 2 The brake control system 100 of the vehicle comprises a perception unit 110, a determination unit 120, and a control unit 130, wherein The perception unit 110 is configured to acquire the road adhesion coefficient of the road on which the vehicle travels, the slope angle of the vehicle, the mass, and the confidence degree corresponding to the road adhesion coefficient when receiving a parking instruction signal and the vehicle is in a parking state.

[0080] The determination unit 120 is configured to determine the target parking force of the vehicle according to the road adhesion coefficient, the slope angle, the mass, and the confidence degree corresponding to the road adhesion coefficient, and generate a brake control instruction according to the target parking force.

[0081] The control unit 130 is configured to control the vehicle to brake according to the brake control instruction, so that the parking force of the vehicle reaches the target parking force, and the brake parking function of the vehicle is realized.

[0082] In some embodiments, when the road surface adhesion coefficient of the road on which the vehicle travels, the slope angle of the vehicle, the mass of the vehicle, and the confidence corresponding to the road surface adhesion coefficient are acquired, the perception unit 110 is specifically configured to: acquire the longitudinal slope angle, the lateral slope angle, the axle load data, the air suspension pressure data, the engine torque data, the acceleration data, the gear, the wheel speed data, and the yaw rate data of the vehicle; determine the slope angle of the vehicle according to the longitudinal slope angle and the lateral slope angle; determine the mass of the vehicle according to the axle load data and the air suspension pressure data of the vehicle, or determine the mass of the vehicle according to the engine torque data, the acceleration data, and the gear; and determine the road surface adhesion coefficient and the confidence corresponding to the road surface adhesion coefficient according to the wheel speed data, the acceleration data, and the yaw rate data.

[0083] In some embodiments, when the target parking force of the vehicle is determined according to the road surface adhesion coefficient, the slope angle, the mass, and the confidence corresponding to the road surface adhesion coefficient, the determination unit 120 is specifically configured to: query a mapping relationship between the road surface adhesion coefficient, the confidence corresponding to the road surface adhesion coefficient, and the dynamic self-adaptive safety coefficient of the vehicle based on pre-calibration to determine the dynamic self-adaptive safety coefficient according to the road surface adhesion coefficient and the confidence corresponding to the road surface adhesion coefficient; determine the road surface adhesion angle according to the dynamic self-adaptive safety coefficient; and determine the target parking force of the vehicle according to the dynamic self-adaptive safety coefficient, the road surface adhesion angle, the slope angle, and the mass.

[0084] In some embodiments, when the brake control instruction is generated according to the target parking force, the determination unit 120 is specifically configured to: obtain a target reverse control force corresponding to the target parking force according to a pre-set characteristic curve, wherein the characteristic curve is obtained based on a mapping relationship between the target parking force and the target reverse control force; and generate the brake control instruction according to the target reverse control force.

[0085] In some embodiments, the vehicle includes a spring energy storage brake master cylinder and at least one high-precision air pressure regulating valve, and when the vehicle is controlled to brake according to the brake control instruction so that the parking force of the vehicle reaches the target parking force, the control unit 130 is specifically configured to: control the high-precision air pressure regulating valve to adjust the air pressure in the spring chamber of the spring energy storage brake master cylinder according to the brake control instruction, so that the pressure in the spring chamber reaches the target reverse control pressure, thereby making the parking force of the vehicle reach the target parking force.

[0086] In some embodiments, after controlling the vehicle to brake according to the brake control instruction, the control unit 130 is further configured to: acquire the air pressure in the spring chamber of the spring-energized brake master cylinder and the ambient temperature of the vehicle in real time; determine a target pressure change amount according to the target reverse control force and the air pressure in the spring chamber of the spring-energized brake master cylinder; determine a first control instruction for controlling the vehicle to brake according to the ambient temperature and the target pressure change amount; determine a second control instruction for controlling the vehicle to brake according to the target pressure change amount; and adjust the braking state of the vehicle according to the first control instruction and the second control instruction, so that the difference between the pressure in the spring chamber and the target reverse control pressure is within a preset difference range.

[0087] In some embodiments, the control unit 130 is further configured to: calibrate the preset characteristic curve when the vehicle meets a calibration condition; wherein the calibration condition includes: the vehicle is in a parking state and the vehicle mileage reaches a preset mileage threshold and / or the engine start-up times of the vehicle reach a preset number threshold; or a user-issued active calibration instruction is received; or the air pressure in the spring chamber of the spring-energized brake master cylinder deviates from the preset pressure by more than a preset deviation threshold for a preset time.

[0088] In some embodiments, when calibrating the preset characteristic curve, the control unit 130 is specifically configured to: when the vehicle fails, determine a corresponding failure level according to the failure information, and trigger a corresponding failure handling strategy according to the failure level; wherein the failure level includes: a first-level failure, a second-level failure, and a third-level failure; when the failure level is the first-level failure, the corresponding failure handling strategy is to make the pressure in the spring chamber zero so that the spring-energized brake master cylinder outputs the maximum physical force; when the failure level is the second-level failure, the corresponding failure handling strategy is to switch the braking control method of the vehicle to a preset conservative force mode, wherein the preset conservative force mode is a mode in which the physical force output by the spring-energized brake master cylinder is a preset physical force; and when the failure level is the third-level failure, the corresponding failure handling strategy is to dynamically increase the safety margin of the braking control system of the vehicle.

[0089] In some embodiments, the braking control system 100 of the vehicle is further configured to: display the failure level through a user interface, and display corresponding failure alarm information according to the failure level.

[0090] The brake control system 100 of the vehicle according to the present application determines the target parking force of the vehicle according to the road surface adhesion coefficient, the slope angle, the mass, and the confidence degree corresponding to the road surface adhesion coefficient, controls the vehicle brake according to the target parking force, can accurately and reasonably apply appropriate brake force in different scenes, avoids performance overkill and resource mismatch caused by excessive parking force, can avoid accelerated fatigue wear and deformation of brake components caused by long-term bearing of excessive mechanical stress, reduces unnecessary stress borne by the brake components, prolongs the service life of the brake components, reduces the maintenance cost, can reduce the work amount required for the air compressor to overcome the spring force when releasing the parking brake, and further reduces the energy cost. Further, when the vehicle meets the calibration condition, the preset characteristic curve is calibrated, the aging and wear of the spring and other components of the spring energy storage brake master cylinder can be avoided, the change of the maximum physical force of the spring can be avoided, the accuracy of the target parking force can be reduced, and the calculation accuracy of the target parking force can be maintained. Further, the intelligent fault grading safety strategy can provide more reasonable and more fine risk management, the vehicle safety reaches a new height, and the safety and reliability of the brake system of the vehicle are improved.

[0091] To achieve the above object, a third aspect of the present application discloses a vehicle, comprising the vehicle brake control system according to the second aspect of the present application, or a processor, a memory, and a vehicle brake control program stored in the memory and executable on the processor, and the vehicle brake control program is executed by the processor to realize the vehicle brake control method according to the first aspect of the present application.

[0092] According to the vehicle of the embodiment of the present application, the target parking force of the vehicle is determined according to the road adhesion coefficient, the slope angle, the mass, and the confidence degree corresponding to the road adhesion coefficient, the vehicle braking is controlled according to the target parking force, appropriate braking force can be accurately and reasonably applied in different scenes, performance excess and resource mismatch caused by excessive parking force can be avoided, meanwhile, accelerated fatigue wear and deformation of the braking components caused by long-term bearing of excessive mechanical stress can be avoided, unnecessary stress borne by the braking components is reduced, the service life of the braking components is prolonged, maintenance cost is reduced, meanwhile, the work amount required for the air compressor to overcome the spring force when releasing the parking brake is reduced, and energy cost is further reduced. Further, when the vehicle meets the calibration condition, the preset characteristic curve is calibrated, the problem that the accuracy of the target parking force is reduced due to the aging and wear of the spring and other components of the spring energy storage brake master cylinder, and the change of the maximum physical force of the spring is avoided, so that the calculation accuracy of the target parking force is maintained. Further, the intelligent fault grading safety strategy can provide more reasonable and more fine risk management, the vehicle safety reaches a new height, and the safety and reliability of the braking system of the vehicle are improved.

[0093] To achieve the above object, a computer readable storage medium is disclosed in the fourth aspect of the present application, and the computer readable storage medium stores a vehicle braking control program. The vehicle braking control program is executed by a processor to implement the vehicle braking control method according to the first aspect of the present application.

[0094] According to the computer readable storage medium of the embodiment of the present application, when the vehicle braking control program stored on the computer readable storage medium is executed by a processor, the target parking force of the vehicle is determined according to the road adhesion coefficient, the slope angle, the mass, and the confidence degree corresponding to the road adhesion coefficient, the vehicle braking is controlled according to the target parking force, appropriate braking force can be accurately and reasonably applied in different scenes, performance excess and resource mismatch caused by excessive parking force can be avoided, meanwhile, accelerated fatigue wear and deformation of the braking components caused by long-term bearing of excessive mechanical stress can be avoided, unnecessary stress borne by the braking components is reduced, the service life of the braking components is prolonged, maintenance cost is reduced, meanwhile, the work amount required for the air compressor to overcome the spring force when releasing the parking brake is reduced, and energy cost is further reduced. Further, when the vehicle meets the calibration condition, the preset characteristic curve is calibrated, the problem that the accuracy of the target parking force is reduced due to the aging and wear of the spring and other components of the spring energy storage brake master cylinder, and the change of the maximum physical force of the spring is avoided, so that the calculation accuracy of the target parking force is maintained. Further, the intelligent fault grading safety strategy can provide more reasonable and more fine risk management, the vehicle safety reaches a new height, and the safety and reliability of the braking system of the vehicle are improved.

[0095] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily mean the same embodiment or example.

[0096] Although the embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, alternatives, and variations can be made thereto without departing from the principles and spirit of the present application, the scope of which is defined by the claims and their equivalents.

Claims

1. A vehicle braking control method, characterized in that: include: When a parking command signal is received and the vehicle is in a parking state, obtaining a road adhesion coefficient of the vehicle, a slope angle and a mass of the vehicle, and a confidence level corresponding to the road adhesion coefficient; determining a target parking force for the vehicle according to the road adhesion coefficient, the slope angle, the mass, and a confidence level corresponding to the road adhesion coefficient, and generating a braking control command according to the target parking force; The vehicle is braked according to the braking control instruction so that the parking force of the vehicle reaches the target parking force, thereby realizing the braking parking function of the vehicle.

2. The vehicle braking control method according to claim 1, characterized in that: The obtaining of the road adhesion coefficient of the vehicle, the slope angle and mass of the vehicle, and the confidence level corresponding to the road adhesion coefficient includes: Acquiring longitudinal slope angle, transverse slope angle, axle load data, air suspension pressure data, engine torque data, acceleration data, gear position, wheel speed data, and yaw rate data of the vehicle; determining a slope angle of the vehicle based on the longitudinal slope angle and the lateral slope angle; determining the mass of the vehicle according to the axle load data of the vehicle and the air suspension pressure data, or determining the mass of the vehicle according to the engine torque data, the acceleration data, and the gear position; The road adhesion coefficient and a confidence level corresponding to the road adhesion coefficient are determined according to the wheel speed data, the acceleration data, and the yaw rate data.

3. The vehicle braking control method according to claim 1, wherein: The determining the target parking force of the vehicle according to the road adhesion coefficient, the slope angle, the mass, and the confidence level corresponding to the road adhesion coefficient includes: determining the dynamic adaptive safety factor by querying a mapping relationship between a pre-calibrated road adhesion coefficient, a confidence level corresponding to the road adhesion coefficient, and a dynamic adaptive safety factor of the vehicle according to the road adhesion coefficient and the confidence level corresponding to the road adhesion coefficient; determining a road adhesion angle according to the dynamic adaptive safety factor; The target parking force of the vehicle is determined according to the dynamic adaptive safety factor, the road adhesion angle, the slope angle, and the mass.

4. The vehicle braking control method according to claim 1, wherein: Generating a braking control instruction according to the target parking force includes: obtaining a target reverse control force corresponding to the target parking force according to a preset characteristic curve, wherein the characteristic curve is obtained based on a mapping relationship between the target parking force and the target reverse control force; The braking control instruction is generated according to the target reverse control force.

5. The vehicle braking control method according to claim 1, wherein: The vehicle includes a spring energy storage brake cylinder and at least one high-precision air pressure regulating valve, and the braking of the vehicle is controlled according to the brake control instruction so that the parking force of the vehicle reaches the target parking force, including: According to the braking control instruction, the high-precision air pressure regulating valve is controlled to adjust the air pressure in the spring chamber of the spring energy storage brake cylinder so that the pressure in the spring chamber reaches the target reverse control pressure, thereby making the parking force of the vehicle reach the target parking force.

6. The vehicle braking control method according to claim 5, characterized in that: After controlling the vehicle to brake according to the braking control instruction, the method further includes: Real-time acquisition of the air pressure in the spring chamber of the spring energy storage brake cylinder and the ambient temperature of the vehicle; Determining a target pressure change according to the target reverse control force and the air pressure in the spring chamber of the spring energy storage brake cylinder; determining a first control instruction for controlling the vehicle to brake according to the ambient temperature and the target pressure change; determining a second control instruction for controlling the vehicle to brake according to the target pressure change; The braking state of the vehicle is adjusted according to the first control instruction and the second control instruction so that the difference between the pressure in the spring chamber and the target reverse control pressure is within a preset difference range.

7. The vehicle braking control method according to claim 6, characterized in that: Also includes: When the vehicle meets a calibration condition, calibrating the preset characteristic curve; The calibration conditions include: the vehicle is in a parked state and the mileage of the vehicle reaches a preset mileage threshold and / or the number of engine starts of the vehicle reaches a preset number threshold; Alternatively, an active calibration instruction is received from the user; Alternatively, the time during which the deviation between the air pressure in the spring chamber of the spring energy storage brake cylinder and the preset pressure is greater than a preset deviation threshold reaches a preset time.

8. The vehicle braking control method according to claim 7, characterized in that: The calibrating the preset characteristic curve includes: Controlling the high-precision air pressure regulating valve to adjust the air pressure in the spring chamber of the spring energy storage brake cylinder so that the pressure in the spring chamber is zero, and obtaining the maximum physical force of the spring energy storage brake cylinder; The preset characteristic curve is scaled proportionally or nonlinearly corrected according to the difference between the maximum physical force and the preset maximum physical force, so as to calibrate the preset characteristic curve.

9. The vehicle braking control method according to claim 8, characterized in that: Also includes: When a fault occurs in the vehicle, a corresponding fault level is determined according to the fault information, and a corresponding fault handling strategy is triggered according to the fault level; wherein the fault level includes: level one fault, level two fault, and level three fault; When the fault level is the first level fault, the corresponding fault handling strategy is: setting the pressure in the spring chamber to zero so that the spring energy storage brake cylinder outputs the maximum physical force; When the fault level is the second-level fault, the corresponding fault handling strategy is: switching the vehicle's braking control method to a preset conservative force mode, wherein the preset conservative force mode is a mode in which the physical force output by the spring energy storage brake cylinder is a preset physical force; When the fault level is the third-level fault, the corresponding fault handling strategy is: dynamically increasing the safety margin of the vehicle's braking control system.

10. The vehicle braking control method according to claim 9, characterized in that: Also includes: The fault level is displayed through a user interface, and corresponding fault alarm information is displayed according to the fault level.

11. A vehicle braking control system, characterized in that: include: a perception unit, configured to, upon receiving a parking command signal and when the vehicle is in a parking state, obtain a road adhesion coefficient of the vehicle, a slope angle and a mass of the vehicle, and a confidence level corresponding to the road adhesion coefficient; a determining unit, configured to determine a target parking force for the vehicle according to the road adhesion coefficient, the slope angle, the mass, and a confidence level corresponding to the road adhesion coefficient, and generate a braking control instruction according to the target parking force; A control unit is used to control the braking of the vehicle according to the braking control instruction so that the parking force of the vehicle reaches the target parking force, thereby realizing the braking parking function of the vehicle.

12. A vehicle comprising: The vehicle braking control system according to claim 11; or, A processor, a memory, and a vehicle braking control program stored in the memory and executable on the processor, wherein the vehicle braking control program, when executed by the processor, implements the vehicle braking control method according to claims 1-10.

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