Vehicle braking method, device and equipment and storage medium

Abstract

The invention discloses a vehicle braking method, device and equipment and a storage medium, and belongs to the field of vehicle engineering. The method comprises the steps that first braking operation is received, and the first braking operation is used for controlling a hydraulic braking system to conduct hydraulic braking; according to the state of at least one component in the hydraulic braking system, the working state of the hydraulic braking system is determined; and according to the working state of the hydraulic braking system and the running state of the vehicle, an EPB is controlled to conduct linear braking. The method can ensure the driving safety.

Description

Technical Field

[0001] The present application relates to the field of vehicle engineering, and in particular to a vehicle braking method, device, equipment and storage medium. Background Art

[0002] During vehicle braking, the driver presses the brake pedal, and the brake master cylinder generates brake pressure, which enters the brake wheel cylinder through the hydraulic pipeline and pushes the caliper to generate braking force.

[0003] Hydraulic braking systems typically employ a cross-type brake circuit to reduce the risk of unilateral brake failure. However, even with a cross-type hydraulic line layout, the hydraulic brake function still has the risk of failure. If a leak occurs in the hydraulic line or brake cylinder, the brake fluid will decrease, causing the brake system to malfunction. Frequent emergency braking or prolonged braking can cause the brake disc to overheat, reducing the braking effect. Prolonged high-speed driving or frequent braking can increase the brake fluid temperature, causing bubbles to form in the boiling brake fluid. When the temperature exceeds the preset standard, it will cause brake failure. Failure or damage to brake system components such as the brake master cylinder and brake booster can also cause the brake system to malfunction. Summary of the Invention

[0004] This application provides a vehicle braking method, device, equipment, and storage medium to ensure driving safety. The technical solution is as follows:

[0005] According to one aspect of the present application, a vehicle braking method is provided, the method comprising:

[0006] receiving a first braking operation, where the first braking operation is used to control the hydraulic braking system to perform hydraulic braking;

[0007] determining an operating state of the hydraulic brake system based on a state of at least one component in the hydraulic brake system;

[0008] According to the working state of the hydraulic brake system and the driving state of the vehicle, the electronic parking brake system EPB is controlled to perform linear braking.

[0009] According to another aspect of the present application, a vehicle braking device is provided, the device comprising:

[0010] an operating module, configured to receive a first braking operation, wherein the first braking operation is used to control the hydraulic braking system to perform hydraulic braking;

[0011] a determination module, configured to determine an operating state of the hydraulic brake system according to a state of at least one component in the hydraulic brake system;

[0012] The control module is used to control the electronic parking brake system EPB to perform linear braking according to the working state of the hydraulic brake system and the driving state of the vehicle.

[0013] According to another aspect of the present application, a computer device is provided, comprising a processor and a memory, wherein the memory stores at least one instruction, at least one program, a code set, or an instruction set, and the at least one instruction, the at least one program, the code set, or the instruction set is loaded and executed by the processor to implement the vehicle braking method as described above.

[0014] According to another aspect of the present application, a computer-readable storage medium is provided, in which at least one instruction, at least one program, a code set or an instruction set is stored. The at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by a processor to implement the vehicle braking method as described above.

[0015] According to another aspect of the present application, a computer program product or computer program is provided, comprising computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the vehicle braking method provided in various optional implementations of the above aspects.

[0016] The beneficial effects of the technical solution provided by this application include at least:

[0017] EPB (Electronic Parking Brake) is an electronic upgrade of the traditional handbrake, which achieves vehicle parking lock by clamping the brake disc with a caliper motor. However, most users still use EPB for static parking and release functions. The technical solution provided by this application is based on the possibility of failure of the hydraulic brake system and the frequency of use of EPB, to achieve a redundant design of the vehicle braking system and maximize the efficiency of the use of the EPB function. By monitoring the working status of the hydraulic brake system in real time during the hydraulic braking process, the EPB can be flexibly used for linear braking based on the working status of the hydraulic brake system and the form status of the vehicle. When the braking effect of the hydraulic brake system is reduced or there is a brake failure, the EPB can be controlled to drive the caliper motor to clamp the brake disc, assisting hydraulic braking and ensuring the braking performance of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 is a structural schematic diagram of a vehicle braking system provided by an exemplary embodiment of the present application;

[0020] Figure 2 is a flow chart of a vehicle braking method provided by an exemplary embodiment of the present application;

[0021] Figure 3 is a flow chart of a vehicle braking method provided by an exemplary embodiment of the present application;

[0022] Figure 4 is a flow chart of a vehicle braking method provided by an exemplary embodiment of the present application;

[0023] Figure 5 is a flow chart of a vehicle braking method provided by an exemplary embodiment of the present application;

[0024] Figure 6 is a flow chart of a vehicle braking method provided by an exemplary embodiment of the present application;

[0025] Figure 7 is a structural schematic diagram of a vehicle braking device provided by an exemplary embodiment of the present application;

[0026] Figure 8 It is a structural diagram of a computer device provided by an exemplary embodiment of the present application.

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application. DETAILED DESCRIPTION

[0028] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0029] Figure 1 A schematic diagram of a vehicle braking system provided by an exemplary embodiment of the present application is shown, which includes a hydraulic braking system and an EPB system.

[0030] The hydraulic braking system consists of several key components, including the brake pedal 102, brake master cylinder, hydraulic pipeline 105, brake wheel cylinder, brake, ESP (Electronic Stability Program) controller 101, wheel speed sensor 104, etc. It realizes the dynamic braking and static parking functions of the vehicle through mechanical connection and electrical signal coordination.

[0031] The brake pedal 102 serves as the driver command input device and is directly connected to the brake master cylinder through a mechanical linkage. It also transmits the pedal switch signal and pedal travel signal to the ESP controller 101, forming the first control link of human-computer interaction.

[0032] The brake master cylinder converts the pedal force applied by the driver into hydraulic pressure, which is distributed to the brake wheel cylinders of the four wheels through a hydraulic pipeline network.

[0033] Hydraulic piping 105 utilizes a hybrid layout of rigid metal pipes and rubber hoses, ensuring efficient delivery of brake fluid to each wheel cylinder while accommodating the vehicle's suspension movement. Hydraulic pressure sensors are installed at key points in the hydraulic braking system. These sensors continuously monitor the system pressure and provide feedback to the ESP controller 101.

[0034] After receiving the brake fluid pressure from the hydraulic line 105, the wheel cylinder pushes the hydraulic caliper to clamp the brake disc that rotates synchronously with the wheel, thereby generating a braking torque to decelerate the vehicle.

[0035] The ESP controller 101 serves as the intelligent hub of the entire braking system, receiving and processing real-time input signals from multiple sensors, including brake pedal on / off signals, pedal travel signals, hydraulic system pressure, wheel speed sensor data, solenoid valve status, and motor operating status. Using sophisticated control algorithms, the ESP controller precisely adjusts braking force distribution and activates the Antilock Brake System (ABS) or Electronic Stability Control (ESC) functions when wheel slip is detected. Its built-in fault diagnosis module continuously monitors the operating status of each subsystem. If it detects abnormal hydraulic pressure, sensor failure, or other fault conditions, it immediately sends a fault signal and intervention instructions to the EPB control unit via the CAN (Controller Area Network) bus.

[0036] The ESP controller 101 may include a first memory and a first processor. The first memory stores a vehicle braking program; the first processor calls and executes the vehicle braking program to implement the vehicle braking method provided herein. The first memory may include, but is not limited to, the following: random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), and electrically erasable programmable read-only memory (EEPROM).

[0037] The first processor may be composed of one or more integrated circuit chips. Alternatively, the first processor may be a general-purpose processor, such as a central processing unit (CPU) or a network processor (NP). Alternatively, the first processor may implement the vehicle braking method provided herein by running a program or code.

[0038] The EPB system consists of an EPB switch 103, an EPB control unit, and a caliper motor mounted on the brake. The EPB switch 103 receives driver commands; for example, a short press enables static parking and release functions, while a long press activates dynamic braking. The EPB control unit analyzes the system status signal from the ESP controller to determine whether to execute the dynamic braking function and outputs the corresponding motor drive command. The caliper motor precisely controls the clamping force of the motor caliper based on the command, achieving continuous adjustment from light braking to full lock. Optionally, when the vehicle starts, the EPB control unit can automatically release the parking brake based on the gear position signal and the accelerator pedal position.

[0039] The wheel speed sensor 104 can be installed at the hub position of each wheel, and generates a pulse signal by detecting the ring gear rotation speed, which is transmitted to the ESP controller via a shielded wiring harness to provide basic data for the dynamic distribution of braking force.

[0040] The vehicle braking system provided in the embodiment of the present application adopts a redundant design. Even if the hydraulic braking system completely fails, the EPB system can still provide basic braking capacity by directly driving the brake through the motor to ensure driving safety.

[0041] Figure 2This is a flow chart of a vehicle braking method provided by an exemplary embodiment of the present application. Figure 1 The vehicle braking system shown in FIG.

[0042] Step 210: Receive a first braking operation, where the first braking operation is used to control the hydraulic braking system to perform hydraulic braking.

[0043] Exemplarily, the method may be executed by an ESP controller in a vehicle control system.

[0044] The first braking operation may be an operation in which the driver steps on a brake pedal. In response to the first braking operation, the brake pedal may send a switch signal and a braking stroke signal corresponding to the first braking operation to the ESP controller.

[0045] The switch signal indicates the brake pedal's on / off state: on indicates the brake pedal is depressed, and off indicates it's not depressed. The brake stroke signal indicates the distance the brake pedal has been depressed (i.e., the degree to which the brake pedal has been depressed). A greater stroke indicates a greater force applied by the driver, or a greater distance the brake pedal has been depressed. The brake pedal reaches its maximum stroke when the driver fully depresses the brake pedal or the brake pedal is depressed to its lowest point.

[0046] ESP receives the first braking operation, and controls the hydraulic braking system to perform hydraulic braking according to the switch signal of the first braking operation (the switch signal indicates that the current state of the brake pedal is on, or the switch signal can be called an on signal); and controls the hydraulic pressure of the hydraulic brake according to the pedal stroke signal of the first braking operation. The greater the pedal stroke in the pedal stroke signal, the greater the hydraulic pressure, the greater the clamping degree of the hydraulic caliper, and the greater the braking force.

[0047] Step 220: Determine the working state of the hydraulic brake system according to the state of at least one component in the hydraulic brake system.

[0048] During the hydraulic braking process, the ESP controller monitors the status of each component in the hydraulic braking system in real time. When a component fails, it can immediately generate an alarm signal to determine that the working status of the hydraulic braking system is abnormal.

[0049] For example, the ESP controller can monitor the brake pedal switch, brake hydraulic pressure, solenoid valve status, motor status, wheel speed sensor status, etc. in real time.

[0050] Exemplarily, when at least one of the following abnormalities occurs in a component of the hydraulic brake system, the operating state of the hydraulic brake system is determined to be a hydraulic brake system failure:

[0051] (1) The brake pedal switch status is abnormal. For example, the brake pedal is depressed but there is no switch signal and / or pedal travel signal, or the brake pedal is depressed but there is a switch signal and / or pedal travel signal.

[0052] (2) Abnormal brake hydraulic pressure. The ESP controller can detect the line pressure in the hydraulic brake system through the hydraulic pressure sensor. Abnormal brake hydraulic pressure may be too low, too high, or fluctuating. For example, when the brake fluid leaks, the master cylinder seal fails, or air enters the line, the brake hydraulic pressure may be too low; when the proportional valve fails or the ESP hydraulic module is stuck, the brake hydraulic pressure may be too high; when the ABS pump or solenoid valve fails, the brake hydraulic pressure may fluctuate.

[0053] (3) Abnormal solenoid valve status. The solenoid valve is controlled by the ESP controller and is used to adjust the hydraulic pressure of each wheel cylinder. If the solenoid valve is stuck (for example, the solenoid valve is normally open or normally closed), the hydraulic pressure drop cannot be distributed as required; if the coil inside the solenoid valve is broken or short-circuited, the solenoid valve will not respond.

[0054] (4) Abnormal motor status. The motor may be an ESP pump motor, which is used to build up additional hydraulic pressure for emergency adjustments when the ESP is operating. Abnormal motor status may include motor stall (e.g., motor mechanical jam or overload burnout) or circuit failure (e.g., insufficient power supply or control signal error).

[0055] (5) Abnormal wheel speed sensor status. The wheel speed sensor is used to monitor the rotational speed of each wheel and provide key data to the ESP controller. Abnormal wheel speed sensor status may include: signal loss (for example, sensor contamination, open circuit, or magnetic ring damage) and signal drift (for example, electromagnetic interference or aging of internal components). Abnormal wheel speed sensor status may cause the ESP controller to misjudge the wheel status, such as mistakenly identifying a wheel as locked, resulting in incorrect intervention.

[0056] (6) Brake disc abnormalities. For example, the brake disc may be overheated or deformed. When the brake disc is overheated, the friction coefficient of the friction material may decrease due to the high temperature, and the braking distance may be significantly extended. Uneven temperature distribution or rapid cooling (such as wading) may cause local stress deformation of the brake disc, resulting in vibration or abnormal noise.

[0057] For example, the operating state of the hydraulic brake system may be a system failure if at least one of the following is present: an abnormal brake pedal switch state, abnormal brake hydraulic pressure, abnormal solenoid valve state, abnormal motor state, or abnormal wheel speed sensor state. If the brake disc is overheated, the operating state of the hydraulic brake system may be a brake disc overheat.

[0058] When there is no abnormal brake pedal switch state, abnormal brake hydraulic pressure, abnormal solenoid valve state, abnormal motor state, abnormal wheel speed sensor state or abnormal brake disc, the working state of the hydraulic brake system may be normal.

[0059] Step 230: Control the EPB to perform linear braking according to the working state of the hydraulic brake system and the driving state of the vehicle.

[0060] Exemplarily, the driving state of a vehicle may include dynamic and static, where dynamic may refer to the vehicle's driving speed being higher than a first speed threshold; static may refer to the vehicle's driving speed being lower than a second speed threshold or the vehicle being stationary, wherein the first speed threshold is not lower than the second speed threshold.

[0061] For example, the ESP controller can trigger EPB auxiliary braking when the vehicle is driving dynamically and the hydraulic brake system fails. ESP can also trigger EPB auxiliary braking when the vehicle is stationary and the brake disc is overheated.

[0062] In summary, EPB is an electronic upgrade of the traditional handbrake, which achieves vehicle parking lock by clamping the brake disc through the caliper motor. However, most users still use EPB for static parking and release functions. The method provided in this embodiment is based on the failure possibility of the hydraulic brake system and the frequency of use of EPB, to achieve redundant design of the vehicle braking system and maximize the efficiency of the use of the EPB function. By real-time monitoring of the working status of the hydraulic brake system during the hydraulic braking process, EPB can be flexibly used for linear braking based on the working status of the hydraulic brake system and the form status of the vehicle. When the braking effect of the hydraulic brake system is reduced or there is a brake failure, the EPB can be controlled to drive the caliper motor to clamp the brake disc to assist hydraulic braking and ensure the braking performance of the vehicle.

[0063] In an optional embodiment, EPB auxiliary braking can be used while the vehicle is moving.

[0064] Figure 3 This is a flow chart of a vehicle braking method provided by an exemplary embodiment of the present application. Figure 1 The vehicle braking system shown. Figure 2 In the illustrated embodiment, step 230 includes step 231 .

[0065] Step 210: Receive a first braking operation, where the first braking operation is used to control the hydraulic braking system to perform hydraulic braking.

[0066] Step 220: Determine the working state of the hydraulic brake system according to the state of at least one component in the hydraulic brake system.

[0067] Exemplarily, when there is at least one of the following abnormalities in the components of the hydraulic brake system, the working state of the hydraulic brake system is determined to be a hydraulic brake system failure: abnormal brake pedal switch state; abnormal brake hydraulic pressure; abnormal solenoid valve state; abnormal motor state; abnormal wheel speed sensor state.

[0068] Step 231: When the working state is a system failure and the vehicle's running speed is higher than a first speed threshold, a driving signal is intermittently sent to the caliper motor through the EPB to control the caliper to intermittently clamp the brake disc.

[0069] For example, if the operating state is a system failure and the vehicle's speed exceeds a first speed threshold, a second braking operation is received. The second braking operation can be a long press of the EPB switch. The second braking operation triggers the EPB to intervene in dynamic braking. After receiving the second braking operation, the EPB intermittently sends a drive signal to the caliper motor, controlling the caliper to intermittently clamp the brake disc.

[0070] In an optional embodiment, as Figure 4 As shown, the method may include the following steps.

[0071] In step 401, the ESP controller monitors the status of various components, including the motor, solenoid valve, and brake fluid pressure sensor, and determines whether the hydraulic brake system has failed based on the status of each component. If the hydraulic brake system has failed, step 402 is executed; otherwise, conventional braking is performed.

[0072] In step 402, if the hydraulic brake system fails and the driver activates the EPB switch for a prolonged period (for example, the EPB switch activation duration exceeds a threshold), the ESP controller determines whether the vehicle's current speed is greater than 6 kph (kilometers per hour). If so, step 403 is executed. If the vehicle speed does not exceed 6 kph, EPB does not intervene in braking. If the driver does not activate the EPB switch for a prolonged period, the motor calipers do not operate, and EPB does not intervene in braking.

[0073] In step 403 , the ESP controller activates the RWU function, controls the EPB to send a caliper motor drive signal, controls the caliper to intermittently clamp and release, and implements EPB dynamic braking.

[0074] In another optional embodiment, the EPB may adopt a staged intervention mechanism to assist the hydraulic brake system in braking. The staged intervention mechanism may be divided into the following three stages.

[0075] (1) Warning stage: When the ESP motor current exceeds the preset threshold (such as continuous high load) or the wheel speed signal deviation exceeds ±5%, EPB enters the "pre-activation mode" and tentatively intervenes on the rear wheels with low-intensity braking force (such as 5%-10% of the maximum clamping force) to avoid direct takeover and cause ESP logic conflicts.

[0076] (2) Collaborative control phase: If the warning persists (e.g., if it is not restored within 100ms), EPB sends a "capability negotiation signal" to ESP, requesting to share some control rights. At this point, EPB's RWU (Rear Wheel Unlocker) function works in conjunction with ESP's ABS / TCS (Traction Control System), but EPB prioritizes rear wheel braking force, leaving ESP with only the front wheel intervention authority.

[0077] (3) Full takeover phase: If ESP fails completely (e.g., no response timeout), EPB switches to independent control mode, dynamically adjusting the rear wheel clamping force based on the slip ratio (slip ratio = (vehicle speed - wheel speed) / vehicle speed). During dynamic braking, an "asymmetric clamping strategy" can be used to adjust the braking force difference between the left and right rear wheels in real time based on the vehicle's yaw rate. For example, if the vehicle shows a tendency to veer to the left, the clamping force of the right rear wheel is increased by 10%-15%, achieving stable control through torque compensation.

[0078] Exemplarily, when the ESP controller is in a system fault state, the fault duration is less than a time threshold, and the vehicle's speed is higher than a first speed threshold, the ESP controller controls the EPB to enter a warning activation mode, intermittently sending a drive signal of a first current value to the caliper motor via the EPB to control the caliper to intermittently clamp the brake disc; and / or,

[0079] When the working state is a system fault, the fault duration is greater than a time threshold, and the vehicle's driving speed is higher than a first speed threshold, the EPB is controlled to enter a negotiation control mode, and a drive signal is intermittently sent to the caliper motor according to the negotiation result with the hydraulic brake system to control the caliper to intermittently clamp the brake disc; in the negotiation control mode, the EPB is used to control the rear wheel braking force, and the hydraulic brake system is used to control the front wheel braking force; and / or,

[0080] When the working state is system failure, the hydraulic brake system does not respond, and the vehicle's driving speed is higher than the first speed threshold, the EPB is controlled to enter the independent control mode, and the EPB intermittently sends a drive signal to the caliper motor based on the slip rate to control the caliper to intermittently clamp the brake disc.

[0081] In summary, the method provided in this embodiment detects faults in the hydraulic brake system after a power-on self-test. If a fault in the ABS motor or solenoid valve prevents ESP control of the dual brake hydraulic circuits, potentially causing wheel lock and loss of vehicle braking performance and handling stability, the ESP controller sends an internal fault signal to the EPB controller. Upon receiving the fault signal from the ESP, the EPB controller activates the RWU function when the vehicle speed exceeds 6 kph, issuing drive signals to the left and right rear wheel caliper motors to intermittently control the caliper clamping and releasing, thereby enabling the caliper motors to control the vehicle's braking function. This process, activated by the driver's active and prolonged pull-up of the EPB switch, actively activates the RWU function, achieving vehicle braking redundancy and ensuring braking performance.

[0082] The method provided in this embodiment determines whether a hydraulic brake system fault exists based on ESP fault monitoring, such as whether the master cylinder is faulty and whether the wheel cylinder hydraulic pressure is within a reasonable range. If a fault occurs, ESP transmits an internal signal to the EPB control system, which in turn sends a drive signal to the caliper motor to clamp and release the brakes. During service braking, a fault in the ESP hydraulic brake system can cause the service brake function to fail, preventing the vehicle from achieving the desired braking force. In this case, ESP sends an internal demotion signal to the EPB control system, triggering the rear anti-lock braking (RWU) function within the EPB system to assist in braking. While ESP is sending the demotion signal to the EPB control system, the driver does not need to actively hold the EPB switch for an extended period of time. Upon receiving the internal demotion signal from ESP, the EPB control system sends a drive command to the caliper motor to clamp and release the brakes.

[0083] The method provided in this embodiment adopts a phased intervention mechanism to monitor the working status of the hydraulic brake system through multi-dimensional signals, realizes "pre-fault prediction", advances the intervention timing of EPB to the stage of ESP function attenuation, and ensures stable vehicle braking performance.

[0084] In an optional embodiment, EPB assisted braking can be used when the vehicle is parked or traveling at low speed.

[0085] Figure 5 This is a flow chart of a vehicle braking method provided by an exemplary embodiment of the present application. Figure 1 The vehicle braking system shown. Figure 2 In the illustrated embodiment, step 230 includes step 232 .

[0086] Step 210: Receive a first braking operation, where the first braking operation is used to control the hydraulic braking system to perform hydraulic braking.

[0087] Step 220: Determine the working state of the hydraulic brake system according to the state of at least one component in the hydraulic brake system.

[0088] Step 232: When the working state is that the brake disc is overheated and the vehicle's running speed is lower than the second speed threshold, a driving signal is continuously sent to the caliper motor through the EPB to control the caliper to continuously clamp the brake disc.

[0089] Illustratively, when the vehicle's driving speed is lower than a second speed threshold, the ESP controller obtains the brake disc temperature of the brake disc; when the brake disc temperature is higher than the temperature threshold, the EPB continuously sends a drive signal corresponding to the brake disc temperature to the caliper motor to control the caliper to continue clamping; wherein, the current magnitude of the drive signal corresponds to the brake disc temperature, and the current magnitude is used to control the clamping force of the caliper.

[0090] For example, when the brake disc temperature is in a first temperature range (e.g., 300-400°C), the corresponding drive signal current is a first value (e.g., 8A); when the brake disc temperature is in a second temperature range (e.g., 400-500°C), the corresponding drive signal current is a second value (e.g., 10A); when the brake disc temperature is in a third temperature range (e.g., greater than 500°C), the corresponding drive signal current is a third value (e.g., 12A).

[0091] Exemplarily, when the brake disc temperature is higher than a temperature threshold (for example, the temperature threshold may be 300°C), the ESP controller determines the vehicle's braking deceleration attenuation coefficient, which is used to indicate the difference between the vehicle's current deceleration and the expected deceleration corresponding to the current speed. When the vehicle's deceleration attenuation coefficient is greater than a first coefficient threshold, the EPB continuously sends a drive signal corresponding to the brake disc temperature to the caliper motor to control the caliper to continue clamping.

[0092] The brake deceleration coefficient reflects the gradual decrease in actual deceleration over time or temperature during braking due to thermal degradation of the friction material or changes in brake system performance. This coefficient reflects the degree of degradation in braking performance. The brake deceleration coefficient can be calculated by comparing the deviation between the current actual deceleration and the ideal peak deceleration. A greater deviation indicates a more severe reduction in braking performance due to thermal degradation or other factors.

[0093] For example, the ESP controller can determine the brake disc temperature by querying a table based on at least one of the following: a vehicle wheel speed signal, a wheel cylinder pressure signal, an ambient temperature signal, and a vehicle sleep time. For example, brake disc temperatures under different operating conditions can be collected through actual vehicle testing and associated with corresponding vehicle signals (such as the vehicle wheel speed signal, wheel cylinder pressure signal, ambient temperature signal, and vehicle sleep time) to establish a database. During application, the database is queried based on the vehicle wheel speed signal, wheel cylinder pressure signal, ambient temperature signal, and vehicle sleep time to determine the corresponding brake disc temperature.

[0094] The vehicle's wheel speed signal indicates changes in the wheel's rotational state. Since the braking process slows the wheel speed through friction, the vehicle's kinetic energy is converted into heat. The faster the wheel speed decreases, the greater the braking intensity, the more frictional heat generated per unit time, and the more significant the rise in brake disc temperature. For example, during emergency braking, the wheel speed drops sharply, causing a large amount of heat to accumulate on the brake disc in a short period of time. However, during gentle deceleration, the temperature rise is relatively gradual. Therefore, by monitoring the wheel speed change rate (deceleration) in real time, the heat input to the brake disc from the current braking force can be inferred.

[0095] The wheel cylinder pressure signal is correlated with the magnitude of the braking force. In a hydraulic braking system, brake pressure determines the clamping force of the brake pad on the brake disc. Higher pressure increases the positive pressure on the friction contact surface, generating more friction torque and heat. For example, when high braking pressure is maintained on a long downhill slope, the brake disc will gradually heat up due to the continuous heat input. By experimentally calibrating the temperature rise rate at different brake pressures, a pressure-temperature rise mapping table can be established, allowing the current brake disc temperature trend to be estimated based on the real-time pressure value.

[0096] The ambient temperature signal significantly affects the initial brake disc temperature and heat dissipation efficiency. In cold environments, the brake disc's initial temperature is lower. Furthermore, due to the high air density, convection heat dissipation is faster, resulting in a smaller temperature rise under the same braking conditions. In hot weather, however, the brake disc's initial temperature is higher, and the air's heat dissipation capacity is reduced, making heat accumulation more likely. For example, continuous braking during high summer temperatures can cause the brake disc temperature to reach critical levels more quickly. Therefore, ambient temperature can be used as a compensation parameter to refine the temperature estimate based on wheel speed and pressure signals, making it more adaptable to different climate conditions.

[0097] The vehicle's rest time (i.e., the time the vehicle sits idle after being turned off) determines the extent of natural brake disc cooling. When the vehicle stops, the brake disc gradually dissipates heat to the surrounding environment through radiation and convection, with the temperature decreasing approximately exponentially over time. For example, if the vehicle is immediately turned off after an intense drive, the brake disc may remain hot; however, if the vehicle is parked for an extended period, the temperature will gradually drop to the ambient temperature. The remaining temperature of the brake disc can be estimated based on the time the vehicle is turned off.

[0098] In an optional embodiment, as Figure 6 As shown, the method includes the following steps.

[0099] In step 501, the ESP controller monitors the status of the motor, solenoid valve, brake fluid hydraulic sensor and other components, and determines whether the hydraulic brake system has failed based on the status of each component. If it has not failed, the vehicle's braking function is normal and can be used, and step 502 is executed. If it has failed, EPB auxiliary braking is required. For details, please refer to Figure 4 or Figure 5 The embodiment shown.

[0100] When a vehicle is traveling at high speeds, braking for long periods of time, or braking frequently, the brake disc temperature rises dramatically, reducing braking efficiency and potentially causing brake failure. To prevent brake disc overheating from affecting braking performance, real-time monitoring of the brake disc temperature is required while the hydraulic brake system is operating normally.

[0101] In step 502, the ESP controller looks up a table to calculate the brake disc temperature.

[0102] Exemplarily, the EPB controller receives a vehicle wheel speed signal, a brake wheel cylinder pressure signal, an ambient temperature signal, and a vehicle sleep time, and calculates the vehicle brake disc temperature by looking up a table.

[0103] Step 503: When the vehicle brake disc temperature is greater than 300°C, the driver fully depresses the brake pedal, and the vehicle deceleration attenuation coefficient is greater than 1m / s 2 , it is judged that the vehicle's hydraulic braking force is insufficient and the vehicle has brake thermal attenuation, and the EPB is triggered according to the brake disc temperature to control the caliper motor to clamp.

[0104] If the brake disc temperature is not higher than 300℃, or the driver does not fully step on the brake pedal, or the vehicle deceleration attenuation coefficient is not higher than 1m / s 2 , there is no need for EPB to intervene in braking, and conventional braking can be performed using the hydraulic braking system.

[0105] The vehicle deceleration attenuation coefficient can be obtained by looking up the table. The current deceleration is calculated based on the wheel speed. The vehicle deceleration attenuation coefficient is obtained by taking the absolute value of the difference between the vehicle's current deceleration during full braking and the vehicle's peak deceleration in the speed range of the current speed in the table.

[0106] The EPB controls the caliper motor to tighten and release. Within the operating current range of 0-16A, the caliper motor rotates and pushes the piston to achieve a braking force of 0-15,000N. The auxiliary clamping force output by the EPB-controlled caliper is determined by determining the temperature range of the brake disc. The operations performed in specific temperature ranges can be:

[0107] When the brake disc temperature is 300℃~400℃, EPB continuously issues caliper clamping commands, and the motor clamping current is set to 8A;

[0108] When the brake disc temperature is 400℃~500℃, EPB continuously issues caliper clamping commands, and the motor clamping current is set to 10A;

[0109] When the brake disc temperature is above 500°C, EPB continuously issues caliper clamping commands, and the motor clamping current is set to 12A.

[0110] EPB receives brake pedal signals, and when the driver releases the brake pedal, the EPB control system sends a release command to the caliper motor. During this process, the driver does not need to actively pull up the EPB switch.

[0111] For example, while the vehicle is in motion, the EPB switch still has a dynamic braking function. If the ESP hydraulic brake system is functioning properly, the driver holding the EPB switch for a long time triggers the Controlled Deceleration for Parking Brake (CDP) function, which dynamically brakes the vehicle to stabilize braking. If the ESP hydraulic brake system or wheel speed sensor fails, the dynamic braking function degrades to a lower level, and the EPB control system activates rear anti-lock braking.

[0112] In summary, the method provided in this embodiment uses wheel speed and wheel cylinder pressure signals to calculate brake disc temperature during service braking or stationary parking. If frequent braking causes the brake disc temperature to rise, leading to poor braking performance and failure to achieve the desired deceleration, ESP can send a continuous clamping command to the EPB when the brake disc temperature exceeds a set value, assisting the hydraulic brake system in achieving the desired braking force.

[0113] Figure 7 1 is a schematic diagram of the structure of a vehicle braking device provided by an exemplary embodiment of the present application. The device includes:

[0114] An operating module 501 is configured to receive a first braking operation, where the first braking operation is configured to control a hydraulic braking system to perform hydraulic braking;

[0115] a determination module 502, configured to determine an operating state of the hydraulic brake system according to a state of at least one component in the hydraulic brake system;

[0116] The control module 503 is configured to control the electronic parking brake system (EPB) to perform linear braking according to the working state of the hydraulic brake system and the driving state of the vehicle.

[0117] In an optional embodiment, the control module 503 is used to intermittently send a drive signal to the caliper motor through the EPB to control the caliper to intermittently clamp the brake disc when the working state is a system failure and the vehicle's driving speed is higher than a first speed threshold.

[0118] In an optional embodiment, the control module 503 is configured to:

[0119] When the working state is a system fault, the fault duration is less than a time threshold, and the driving speed of the vehicle is higher than a first speed threshold, controlling the EPB to enter a warning activation mode, intermittently sending a drive signal of a first current value to the caliper motor through the EPB to control the caliper to intermittently clamp the brake disc; and / or,

[0120] When the working state is a system fault, the fault duration is greater than a time threshold, and the driving speed of the vehicle is higher than a first speed threshold, the EPB is controlled to enter a negotiation control mode, and a drive signal is intermittently sent to the caliper motor according to the negotiation result with the hydraulic brake system to control the caliper to intermittently clamp the brake disc; in the negotiation control mode, the EPB is used to control the braking force of the rear wheels, and the hydraulic brake system is used to control the braking force of the front wheels; and / or,

[0121] When the working state is a system failure, the hydraulic brake system does not respond, and the vehicle's driving speed is higher than a first speed threshold, the EPB is controlled to enter an independent control mode, and the EPB intermittently sends a drive signal to the caliper motor based on the slip rate to control the caliper to intermittently clamp the brake disc.

[0122] In an optional embodiment, the control module 503 is used to continuously send a drive signal to the caliper motor through the EPB to control the caliper to continuously clamp the brake disc when the working state is that the brake disc is overheated and the driving speed of the vehicle is lower than a second speed threshold.

[0123] In an optional embodiment, the control module 503 is configured to obtain a brake disc temperature of the brake disc when the driving speed of the vehicle is lower than a second speed threshold;

[0124] The control module 503 is configured to continuously send a drive signal corresponding to the brake disc temperature to the caliper motor via the EPB to control the caliper to continuously clamp when the brake disc temperature is higher than a temperature threshold;

[0125] The current magnitude of the driving signal corresponds to the temperature of the brake disc, and the current magnitude is used to control the clamping force of the caliper.

[0126] In an optional embodiment, the control module 503 is configured to determine a braking deceleration attenuation coefficient of the vehicle when the brake disc temperature is higher than a temperature threshold, wherein the braking deceleration attenuation coefficient is used to indicate a difference between a current deceleration of the vehicle and an expected deceleration corresponding to a current speed;

[0127] The control module 503 is configured to continuously send a drive signal corresponding to the brake disc temperature to the caliper motor through the EPB to control the caliper to continuously clamp when the vehicle deceleration attenuation coefficient is greater than a first coefficient threshold.

[0128] In an optional embodiment, the control module 503 is configured to determine the brake disc temperature by looking up a table based on at least one of a vehicle wheel speed signal, a brake cylinder pressure signal, an ambient temperature signal, and a vehicle sleep time.

[0129] In an optional embodiment, the determining module 502 is configured to determine that the operating state of the hydraulic brake system is a hydraulic brake system failure when at least one of the following abnormalities occurs in a component of the hydraulic brake system:

[0130] The brake pedal switch status is abnormal;

[0131] Abnormal brake hydraulic pressure;

[0132] The solenoid valve is in abnormal state;

[0133] The motor status is abnormal;

[0134] The wheel speed sensor is in abnormal state;

[0135] The brake disc is abnormal.

[0136] It should be noted that the vehicle braking device provided in the above embodiment is merely illustrated by the division of the aforementioned functional modules. In actual applications, the aforementioned functions can be assigned to different functional modules as needed, i.e., the internal structure of the device can be divided into different functional modules to perform all or part of the functions described above. Furthermore, the vehicle braking device provided in the above embodiment and the vehicle braking method embodiment are based on the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0137] Embodiments of the present application further provide a computer device comprising: a processor and a memory, wherein the memory stores at least one instruction, at least one program, code set, or instruction set, and the processor loads and executes the at least one instruction, at least one program, code set, or instruction set to implement the vehicle braking methods provided in the aforementioned method embodiments. The computer device can be implemented as an ESP controller.

[0138] For example, Figure 8 It is a structural diagram of a computer device provided by an exemplary embodiment of the present application.

[0139] Typically, the computer device 1700 includes a processor 1701 and a memory 1702 .

[0140] The processor 1701 may include one or more processing cores, such as a quad-core processor, an octa-core processor, etc. The processor 1701 may be implemented in at least one hardware form of a DSP (Digital Signal Processing), an FPGA (Field-Programmable Gate Array), or a PLA (Programmable Logic Array). The processor 1701 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 1701 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 1701 may also include an AI (Artificial Intelligence) processor, which is used to handle computing operations related to machine learning.

[0141] Memory 1702 may include one or more computer-readable storage media, which may be non-transitory. Memory 1702 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in memory 1702 is used to store at least one instruction, which is executed by processor 1701 to implement the vehicle braking method provided in the method embodiment of the present application.

[0142] Those skilled in the art will understand that Figure 8 The structure shown in the figure does not constitute a limitation on the computer device 1700, and the computer device 1700 may include more or fewer components than shown in the figure, or combine some components, or adopt a different component arrangement.

[0143] A computer-readable storage medium is also provided in an embodiment of the present application, which stores at least one instruction, at least one program, code set or instruction set. When the at least one instruction, at least one program, code set or instruction set is loaded and executed by a processor of a computer device, the vehicle braking method provided by the above-mentioned method embodiments is implemented.

[0144] The present application also provides a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the vehicle braking method provided by each of the above method embodiments.

[0145] Those skilled in the art will understand that all or part of the steps of implementing the above embodiments may be accomplished by hardware, or may be accomplished by a program instructing the relevant hardware, and the program may be stored in a computer-readable storage medium, and the above-mentioned readable storage medium may be a read-only memory, a disk or an optical disk, etc.

[0146] The above description is merely an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent switching, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A vehicle braking method, characterized in that: The method comprises: receiving a first braking operation, where the first braking operation is used to control the hydraulic braking system to perform hydraulic braking; determining an operating state of the hydraulic brake system based on a state of at least one component in the hydraulic brake system; According to the working state of the hydraulic brake system and the driving state of the vehicle, the electronic parking brake system EPB is controlled to perform linear braking.

2. The method according to claim 1, characterized in that The method of controlling the electronic parking brake system (EPB) to perform linear braking according to the working state of the hydraulic brake system and the driving state of the vehicle includes: When the working state is a system failure and the driving speed of the vehicle is higher than a first speed threshold, the EPB intermittently sends a driving signal to the caliper motor to control the caliper to intermittently clamp the brake disc.

3. The method according to claim 2, characterized in that When the working state is a system failure and the driving speed of the vehicle is higher than a first speed threshold, intermittently sending a driving signal to the caliper motor through the EPB to control the caliper to intermittently clamp the brake disc, including: When the working state is a system fault, the fault duration is less than a time threshold, and the driving speed of the vehicle is higher than a first speed threshold, controlling the EPB to enter a warning activation mode, intermittently sending a drive signal of a first current value to the caliper motor through the EPB to control the caliper to intermittently clamp the brake disc; and / or, When the working state is a system fault, the fault duration is greater than a time threshold, and the driving speed of the vehicle is higher than a first speed threshold, the EPB is controlled to enter a negotiation control mode, and a drive signal is intermittently sent to the caliper motor according to the negotiation result with the hydraulic brake system to control the caliper to intermittently clamp the brake disc; in the negotiation control mode, the EPB is used to control the braking force of the rear wheels, and the hydraulic brake system is used to control the braking force of the front wheels; and / or, When the working state is a system failure, the hydraulic brake system does not respond, and the vehicle's driving speed is higher than a first speed threshold, the EPB is controlled to enter an independent control mode, and the EPB intermittently sends a drive signal to the caliper motor based on the slip rate to control the caliper to intermittently clamp the brake disc.

4. The method according to claim 1, wherein The method of controlling the electronic parking brake system (EPB) to perform linear braking according to the working state of the hydraulic brake system and the driving state of the vehicle includes: When the working state is that the brake disc is overheated and the driving speed of the vehicle is lower than a second speed threshold, the EPB continuously sends a driving signal to the caliper motor to control the caliper to continuously clamp the brake disc.

5. The method according to claim 4, characterized in that When the working state is that the brake disc is overheated and the driving speed of the vehicle is lower than a second speed threshold, continuously sending a driving signal to the caliper motor through the EPB to control the caliper to continuously clamp the brake disc, including: acquiring a brake disc temperature of the brake disc when the running speed of the vehicle is lower than a second speed threshold; When the temperature of the brake disc is higher than a temperature threshold, the EPB continuously sends a drive signal corresponding to the brake disc temperature to the caliper motor to control the caliper to continuously clamp; The current magnitude of the driving signal corresponds to the temperature of the brake disc, and the current magnitude is used to control the clamping force of the caliper.

6. The method according to claim 5, characterized in that When the temperature of the brake disc is higher than a temperature threshold, continuously sending a drive signal corresponding to the brake disc temperature to the caliper motor through the EPB to control the caliper to continuously clamp, including: determining a braking deceleration attenuation coefficient of the vehicle when the brake disc temperature is higher than a temperature threshold, the braking deceleration attenuation coefficient being used to indicate a difference between a current deceleration of the vehicle and an expected deceleration corresponding to a current speed; When the vehicle deceleration attenuation coefficient is greater than a first coefficient threshold, a drive signal corresponding to the brake disc temperature is continuously sent to the caliper motor via the EPB to control the caliper to be continuously clamped.

7. The method according to claim 5, characterized in that The obtaining of the brake disc temperature of the brake disc includes: The brake disc temperature is determined by looking up a table based on at least one of a vehicle wheel speed signal, a brake wheel cylinder pressure signal, an ambient temperature signal, and a vehicle sleep time.

8. The method according to any one of claims 1 to 7, characterized in that: Determining the operating state of the hydraulic brake system according to the state of at least one component in the hydraulic brake system includes: The operating state of the hydraulic brake system is determined to be a hydraulic brake system failure when at least one of the following abnormalities occurs in a component of the hydraulic brake system: The brake pedal switch status is abnormal; Abnormal brake hydraulic pressure; The solenoid valve is in abnormal state; The motor status is abnormal; The wheel speed sensor is in abnormal state; The brake disc is abnormal.

9. A vehicle braking device, characterized in that: The device comprises: an operating module, configured to receive a first braking operation, wherein the first braking operation is used to control the hydraulic braking system to perform hydraulic braking; a determination module, configured to determine an operating state of the hydraulic brake system according to a state of at least one component in the hydraulic brake system; The control module is used to control the electronic parking brake system EPB to perform linear braking according to the working state of the hydraulic brake system and the driving state of the vehicle.

10. A computer device, characterized in that: The computer device includes a processor and a memory, wherein the memory stores at least one program, and the at least one program is loaded and executed by the processor to implement the vehicle braking method according to any one of claims 1 to 8.

11. A computer-readable storage medium, characterized in that The readable storage medium stores at least one program, and the at least one program is loaded and executed by the processor to implement the vehicle braking method according to any one of claims 1 to 8.

12. A computer program product, characterized in that The computer program product includes computer instructions, which are stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device performs the vehicle braking method according to any one of claims 1 to 8.

Images