Maximum dominant braking force calculation method, device, equipment and medium

Abstract

The invention provides a maximum dominant braking force calculation method and device, equipment and a medium. The method comprises the following steps: firstly, acquiring regenerative braking force of a vehicle, brake temperature of each axle, air pressure of an air reservoir and axle load; and for each axle, determining the braking capacity of the axle according to the regenerative braking force, the brake temperature of the axle and the air cylinder air pressure. And finally, the maximum disposable braking force of the vehicle is determined according to a preset adhesion coefficient, the axle load of each axle and the braking capacity, and the preset adhesion coefficient is the adhesion coefficient corresponding to the high-adhesion road surface. The calculation accuracy of the disposable braking force is improved.

Description

Technical Field

[0001] This application relates to the technical field of vehicle braking, and particularly to a method, device, equipment and medium for calculating the maximum available braking force. Background Art

[0002] During the driving process of a vehicle, the braking system is an important system to ensure that the vehicle can decelerate or stop. The braking system relies on sufficient braking force to stop the vehicle. Insufficient braking force will result in a long braking distance or even the inability to stop the vehicle. Therefore, when the driver uses the braking system, being able to determine the magnitude of the available braking force is extremely crucial for safe driving.

[0003] In the prior art, the available braking force is determined based on the state of the vehicle itself. The currently available braking torque can be determined according to the relationship between state data such as battery power and battery temperature and the braking torque, so as to determine the available braking force.

[0004] However, there is a problem of low calculation accuracy of the available braking force in the prior art. Summary of the Invention

[0005] Embodiments of this application provide a method, device, equipment and medium for calculating the maximum available braking force to improve the calculation accuracy of the available braking force.

[0006] In a first aspect, embodiments of this application provide a method for calculating the maximum available braking force, including:

[0007] Obtain the regenerative braking force of the vehicle, the brake temperature of each axle, the air storage tank pressure, and the axle load;

[0008] For each axle, determine the braking ability of the axle according to the regenerative braking force, the brake temperature of the axle, and the air storage tank pressure;

[0009] Determine the maximum available braking force of the vehicle according to the preset adhesion coefficient, the axle load of each axle, and the braking ability. The preset adhesion coefficient is the adhesion coefficient corresponding to a high-adhesion road surface.

[0010] In a possible implementation manner, for each axle, determine the friction coefficient between the friction lining and the brake disc in the brake of the axle according to the brake temperature of the axle; determine the pressing force of the friction lining in the brake of the axle according to the air storage tank pressure of the axle; determine the braking force of the brake of the axle according to the friction coefficient and the pressing force; determine the braking ability of each axle according to the regenerative braking force and the braking force of the brake of each axle.

[0011] In a possible implementation manner, determine the braking force of the brake of the front axle as the braking ability of the front axle; determine the sum of the braking force of the brake of the rear axle and the regenerative braking force as the braking ability of the rear axle.

[0012] In a possible implementation, for each axle, the maximum ground adhesion of the axle is determined according to the axle load of the axle and a preset adhesion coefficient; the smaller value between the maximum ground adhesion and the braking capacity is determined as the maximum available ground braking force of the axle; the sum of the maximum available ground braking force of the front axle and the maximum available ground braking force of the rear axle is determined as the maximum available braking force of the vehicle.

[0013] In a possible implementation, the regenerative braking force of the vehicle is determined by obtaining the motor negative torque that the vehicle can execute.

[0014] In a possible implementation, if the maximum available braking force of the vehicle is less than a preset braking force, an alarm message is output, and the alarm message is used to remind the user that the vehicle can no longer provide the braking force to support the vehicle to decelerate or stop within a preset distance.

[0015] In a possible implementation, according to the current pedal depth of the vehicle and a preset mapping relationship, the current output air pressure corresponding to the current pedal depth is determined, and the preset mapping relationship is used to represent the corresponding relationship between the pedal depth and the output air pressure; the current braking intensity of the vehicle is determined according to the current output air pressure; the current braking intensity and the maximum available braking force are displayed.

[0016] In a second aspect, an embodiment of the present application provides a maximum available braking force calculation device, including:

[0017] An acquisition module, configured to acquire the regenerative braking force of the vehicle, the brake temperature of each axle, the air pressure of the air storage tank, and the axle load;

[0018] A first determination module, configured to determine the braking capacity of each axle according to the regenerative braking force, the brake temperature of the axle, and the air pressure of the air storage tank for each axle;

[0019] A second determination module, configured to determine the maximum available braking force of the vehicle according to a preset adhesion coefficient, the axle load of each axle, and the braking capacity, where the preset adhesion coefficient is the adhesion coefficient corresponding to a high-adhesion road surface.

[0020] In a third aspect, an embodiment of the present application provides an electronic device, including: a memory, a processor;

[0021] The memory stores computer-executable instructions;

[0022] The processor executes the computer-executable instructions stored in the memory, so that the processor executes the above first aspect and / or various possible implementation manners of the first aspect.

[0023] Fourthly, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the first aspect and / or various possible implementation manners of the first aspect as described above.

[0024] The maximum available braking force calculation method, device, equipment and medium provided by the embodiments of the present application first obtain the regenerative braking force of the vehicle, the brake temperature of each axle, the air storage tank pressure and the axle load, and use these as the evaluation basis for evaluating the braking ability of the vehicle. Then, for each axle, according to the regenerative braking force, the brake temperature of the axle and the air storage tank pressure, the braking ability of the axle is determined, thereby quantifying the braking ability of the vehicle. Finally, according to the preset adhesion coefficient, the axle load of each axle and the braking ability, after evaluating the friction force that the road surface can provide, the maximum available braking force of the vehicle is determined, where the preset adhesion coefficient is the adhesion coefficient corresponding to a high-adhesion road surface. Thereby, the calculation accuracy of the available braking force is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings herein are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with the present application and used together with the specification to explain the principles of the present application.

[0026] Figure 1 It is a maximum available braking force calculation system provided by an embodiment of the present application;

[0027] Figure 2 It is a schematic flow chart of the maximum available braking force calculation method provided by an embodiment of the present application Figure 1 ;

[0028] Figure 3 It is a schematic flow chart of the maximum available braking force calculation method provided by an embodiment of the present application Figure 2 ;

[0029] Figure 4 It is a schematic structural diagram of the maximum available braking force calculation device provided by an embodiment of the present application;

[0030] Figure 5 It is a schematic structural diagram of the electronic device provided by an embodiment of the present application.

[0031] Through the above-mentioned drawings, the clear embodiments of the present application have been shown, and there will be more detailed descriptions hereinafter. These drawings and text descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] Exemplary embodiments will be described in detail herein, and examples thereof are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application.

[0033] First, the terms related to the present application are explained: AEBS: It refers to Automatic Emergency Braking System, that is, the automatic emergency braking system. This system is used to automatically brake the vehicle when it detects an impending collision to avoid or reduce the impact of the collision; EBS: It refers to Electronic Braking System, that is, the electronic braking system. This system optimizes and manages the braking process of the vehicle through electronic control technology, improving the braking response speed and safety; VCU: It refers to Vehicle Control Unit, that is, the vehicle control unit. As the core of the vehicle control system, it is responsible for coordinating and managing the operation of each subsystem including the power system, braking system, and on-vehicle equipment to ensure the efficient and safe operation of the vehicle; MCU: It refers to Motor Control Unit, that is, the motor control unit. It is specifically used to control the drive motor in an electric vehicle and adjust the rotational speed and torque output of the motor in real time to achieve the best power performance and energy efficiency; ECU: It refers to Electronic Control Unit, that is, the electronic control unit. It is used to receive sensor signals and control the operation of each system of the vehicle to achieve performance optimization, energy consumption reduction, and safety guarantee.

[0034] Figure 1 For the maximum available braking force calculation system provided by the embodiments of the present application, as Figure 1 shown, the system includes the electronic control unit of the vehicle's automatic emergency braking system (i.e., AEBS-ECU), instrument panel, motor control unit (i.e., MCU), vehicle control unit (i.e., VCU), electronic control unit of the electronic braking system (i.e., EBS-ECU), axle load sensor, air pressure sensor, temperature sensor, front axle module, rear axle module, front air reservoir, and rear air reservoir.

[0035] The maximum available braking force calculation system adds a temperature sensor at the wheel end of the wheel, an air pressure sensor on the air reservoir, and axle load sensors on the front axle and rear axle.

[0036] Among them, the instrument is used to display vehicle status data, including the currently used braking intensity and the maximum available braking intensity, so as to give the driver a good driving experience.

[0037] The front axle module is used to control the braking pressure distribution on the front axle. The front axle module controls Wheel 1 and Wheel 2; the rear axle module is used to control the braking pressure distribution on the rear axle. The rear axle module controls Wheel 3 and Wheel 4.

[0038] In Figure 1 it, the black dots are used to represent the air pressure sensors, and the black rectangles are used to represent the temperature sensors. The air pressure sensors are installed on the front air storage tank and the rear air storage tank. The temperature sensors are installed at the wheel ends of Wheel 1, Wheel 2, Wheel 3 and Wheel 4.

[0039] Among them, the air pressure sensors are used to collect the air pressures of the front and rear air storage tanks. The axle load sensors are used to collect the front and rear axle loads. The temperature sensors are used to collect the temperatures of the front and rear brakes.

[0040] During the driving process of the vehicle, the braking system is the key system to ensure the vehicle to decelerate or stop. The braking system requires sufficient braking force to make the vehicle decelerate or stop as expected. Insufficient braking force will lead to a long braking distance of the vehicle or even the vehicle cannot be braked. Therefore, during the driving process of the driver, being able to know the magnitude of the available braking force of the current vehicle is of extremely important significance for safe driving. Among them, the technology for determining the magnitude of the available braking force is extremely critical.

[0041] In the prior art, by analyzing vehicle status data such as the vehicle battery temperature and the vehicle battery power in real time, and combining the relationship between the preset status data and the braking torque, the current available braking torque is determined, so as to evaluate the available braking force. However, when the friction force that the ground can provide is not enough to meet the requirements of the available braking force, at this time, when the driver brakes with the evaluated available braking force, the wheels may "lock up" due to insufficient friction force. It can be seen that the prior art has the problem of low calculation accuracy of the available braking force.

[0042] In response to this, the maximum available braking force calculation method provided by the present application takes into account that the available braking force can be jointly evaluated by combining the braking ability and the friction force that the ground can provide. Among them, the braking ability can be calculated by the regenerative braking force and the brake braking force. And the brake braking force depends on the brake temperature and the air pressure of the front and rear circuits. At the same time, considering that the friction force that a road surface with a high adhesion coefficient can provide is large, the friction force is determined by combining the axle load and the adhesion coefficient. Thus, by combining the road surface conditions and the vehicle's own ability, the calculation accuracy of the vehicle's available braking force is improved.

[0043] The technical solution of the present application and how the technical solution of the present application solves the above technical problems will be described in detail below with specific embodiments. The following several specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below with reference to the accompanying drawings.

[0044] Figure 2 Flow schematic of the maximum available braking force calculation method provided by the embodiments of the present application Figure 1 , the vehicle to be controlled involved in this method is a new energy vehicle, such as Figure 2 As shown, this method includes:

[0045] S201. Obtain the regenerative braking force of the vehicle, the brake temperature of each axle, the air storage tank air pressure, and the axle load.

[0046] Among them, the regenerative braking force is the force that changes the motion state of the vehicle. When the vehicle needs to decelerate or stop, the drive motor is converted into a generator, and the kinetic energy of the vehicle is converted into electrical energy through the principle of electromagnetic induction and stored in the on-vehicle battery for subsequent use. During this process, since the generator exerts a resistance on the change of the vehicle's motion state, the vehicle speed is reduced, that is, the regenerative braking force is the force that changes the motion state of the vehicle.

[0047] The brake temperature refers to the temperature increase of the brake components caused by the heat generated due to friction when the braking system is working.

[0048] Exemplarily, the brake components are brake discs, brake drums, etc.

[0049] The air storage tank air pressure refers to the pressure of the compressed air inside the air storage tank in the air braking system.

[0050] The axle load refers to the vertical load acting on an axle, and the axle load includes all the forces such as the vehicle's own weight and the load weight applied to the axle.

[0051] In a possible implementation manner, obtain the motor's available negative torque of the vehicle, and determine the regenerative braking force of the vehicle.

[0052] Among them, the motor's available negative torque refers to the reverse torque that the motor can exert on the vehicle when operating as a generator, which is used to decelerate or brake the vehicle.

[0053] According to the motor's available negative torque, the function relationship can be used to calculate the regenerative braking force. Among them, is the regenerative braking force, is the motor's available negative torque.

[0054] In a possible implementation manner, when obtaining the motor's available negative torque After that, according to the formula , the wheel-end torque can be calculated , where is the transmission ratio. Then, according to the formula , the regenerative braking force is calculated, where is the wheel rolling radius.

[0055] Exemplarily, when the maximum negative torque of the motor is 200 N·m, the transmission ratio is 8.5, and the wheel rolling radius is 0.3 m, the wheel-end torque = = 200×8.5 = 1700 N·m can be calculated, and then the regenerative braking force = is determined.

[0056] S202. For each axle, determine the braking capacity of the axle according to the regenerative braking force, the brake temperature of the axle, and the air storage tank pressure.

[0057] Among them, the braking capacity of the axle refers to the ability of the vehicle to be forced to decelerate or stop during driving, or to maintain a certain speed when going downhill.

[0058] It should be understood that the braking capacity depends on the braking force of the brake, and the braking force of the brake is mainly provided by the frictional braking force.

[0059] Therefore, in a possible implementation, considering that the frictional braking force is mainly affected by the air pressure in the front and rear circuits and the brake temperature. And the frictional braking force is proportional to the air pressure value in the circuit and negatively correlated with the brake temperature. The higher the brake temperature, the lower the friction coefficient of the friction plate, and the lower the braking efficiency. When the temperature is high (up to above 500°C), the friction material (such as resin, metal powder) is carbonized due to high temperature, and the friction coefficient drops suddenly. Therefore, first, for each axle, according to the brake temperature of the axle, determine the friction coefficient between the friction lining and the brake disc in the brake of the axle.

[0060] Then, according to the air storage tank pressure of the axle, determine the pressing force of the friction lining in the brake of the axle. Then, according to the friction coefficient and the pressing force, determine the braking force of the brake of the axle. Finally, according to the regenerative braking force and the braking force of the brake of each axle, determine the braking capacity of each axle.

[0061] Among them, the friction coefficient between the friction lining and the brake disc is used to determine the magnitude of the frictional force that can be generated, thereby affecting the vehicle's deceleration ability. A high friction coefficient means a greater frictional force, thus having a more powerful braking force, while the braking force of a low friction coefficient may be insufficient.

[0062] The pressing force of the friction lining refers to the normal force applied by the braking system to the friction lining during braking. The friction lining can be understood as the brake pad. The pressing force causes the brake pad to tightly press against the brake disc, thereby achieving vehicle deceleration or stopping through the frictional force between the two.

[0063] In practical applications, first, use the formula to calculate the friction coefficient, where is the friction coefficient, is the brake temperature of the axle. Then use the formula to calculate the pressing force of the friction lining, where, is the pressing force, is the air storage tank air pressure. Then, according to the formula calculate the braking force of the brake, where, is the braking force of the brake.

[0064] Exemplarily, a certain friction material can be measured based on multiple experiments, which can be represented by a mapping relationship. The friction coefficients for temperature ranges (0, 100), (100, 200), (200, 300), (300, 400), (400, 500) are 0.4, 0.38, 0.35, 0.30, 0.25 respectively. When the brake temperature of the front axle is 250 °C, its friction coefficient is 0.35. At the same time, when the brake temperature of the rear axle is 350 °C, its friction coefficient is 0.30.

[0065] Next, according to the formula calculate the pressing force of the friction lining, where, is the effective area of the air chamber piston, is the pre-tightening force of the return spring. When is 0.002 、 is 500 N, based on the air storage tank air pressure of the front axle being 6 bar, the pressing force of the front axle can be calculated as 700 N. At the same time, based on the air storage tank air pressure of the rear axle being 8 bar, the pressing force of the front axle can be calculated as 1700 N.

[0066] Then, according to calculate the braking force of the front axle brake 245 N. According to calculate the braking force of the rear axle brake .

[0067] In practical applications, the regenerative braking force only acts on the drive axle, generally the rear axle. Therefore, in one possible implementation, the braking force of the front axle brake is determined as the braking capacity of the front axle. And the sum of the braking force of the rear axle brake and the regenerative braking force is determined as the braking capacity of the rear axle.

[0068] Exemplarily, the braking capacity of the front axle is represented by the value of, that is, the braking capacity of the front axle is 245 N. The braking capacity of the rear axle is represented by + When is 200 N, that is, the braking capacity of the rear axle is 510 + 200 = 710 N.

[0069] S203. Determine the maximum available braking force of the vehicle according to the preset adhesion coefficient, the axle load of each axle, and the braking capacity.

[0070] Among them, the adhesion coefficient is used to measure the magnitude of the reverse force that the ground can provide to the tire. The preset adhesion coefficient is the adhesion coefficient corresponding to a high-adhesion road surface, and the high adhesion coefficient represents the maximum grip under ideal road conditions.

[0071] Among them, a high-adhesion road surface refers to a road surface with a relatively high adhesion coefficient. When the vehicle is driving on such a road surface, a large adhesion force can be generated between the tire and the road surface, and it is not easy to slip, and the driving safety is high. According to international standards, the adhesion coefficient of a high-adhesion road surface is about 0.8. For example, the adhesion coefficient of a dry, good asphalt or concrete road surface can reach 0.7 - 0.8 and can be regarded as a high-adhesion road surface.

[0072] In practical applications, the determination of the adhesion coefficient can be adjusted according to the road surface conditions. For example, high-precision cameras can be installed at key road sections or on the vehicle to judge the road surface conditions. The camera continuously collects road surface images, and uses image recognition algorithms to analyze the images to identify whether there is water accumulation, icing, snow accumulation on the road surface, as well as the characteristics of the road surface material, texture, etc. If water accumulation is identified on the road surface, the adhesion coefficient can be adjusted according to information such as the area and depth of the water accumulation, combined with the pre-set road surface adhesion coefficient change model under different conditions.

[0073] The maximum available braking force of the vehicle refers to the maximum deceleration or braking force that the vehicle can provide.

[0074] It should be understood that when the vehicle brakes, if the braking force applied by the brake exceeds the maximum adhesion between the tire and the ground, the wheel will stop rotating and skid on the ground, that is, the "locking" phenomenon. At this time, the friction form between the tire and the ground changes from rolling friction to sliding friction, which not only causes the braking force to decrease, but also leads to problems such as loss of direction control and increased braking distance, seriously affecting driving safety. Therefore, the maximum braking force that the vehicle can actually obtain is limited by the ground adhesion conditions, and the maximum available braking force of the vehicle should consider the adhesion coefficient corresponding to the high-adhesion road surface, that is, the high adhesion coefficient.

[0075] In a possible implementation, first for each axle, according to the axle load of the axle and the preset adhesion coefficient, determine the maximum ground adhesion of the axle. Then, take the smaller value between the maximum ground adhesion and the braking capacity as the maximum available ground braking force of the axle. Finally, take the sum of the maximum available ground braking force of the front axle and the maximum available ground braking force of the rear axle as the maximum available braking force of the vehicle.

[0076] Among them, the ground adhesion is used to measure the grasping force that the ground can provide to the wheel, and the maximum ground adhesion of the axle is the maximum grasping force provided by the road surface under the high adhesion coefficient.

[0077] Exemplarily, according to the formula = calculate the maximum ground adhesion of the front axle, where is the maximum ground adhesion of the front axle, is the high adhesion coefficient, is the load of the front axle. Similarly, according to the formula = calculate the maximum ground adhesion of the rear axle, where is the maximum ground adhesion of the rear axle, is the load of the rear axle.

[0078] Then, according to the formula determine the maximum available ground braking force of the front axle, and according to the formula determine the maximum available ground braking force of the rear axle. Thus, the maximum available braking force of the vehicle can be determined as .

[0079] It should be understood that when the maximum ground adhesion is greater than the braking capacity, it means that the ground can provide sufficient grasping force to the vehicle. At this time, the maximum available ground braking force is the calculated braking capacity; when the maximum ground adhesion is less than the braking capacity, it means that the ground cannot provide the required grasping force. If the calculated braking capacity is still used as the maximum available ground braking force, the wheel will "lock", so the maximum ground adhesion is used as the maximum available ground braking force.

[0080] In practical applications, the maximum braking deceleration can be determined according to the vehicle mass. That is, based on the vehicle mass , the maximum available braking deceleration is calculated . The maximum braking deceleration and the maximum available braking force represent the maximum available braking intensity of the vehicle.

[0081] It should be understood that the maximum available braking force of the vehicle reflects the braking force that the vehicle can provide. When the maximum available braking force is lower than a certain threshold, it means that the vehicle cannot provide sufficient braking force, and at this time, a warning needs to be given. Therefore, in a possible implementation, if the maximum available braking force of the vehicle is less than the preset braking force, an alarm message is output, and the alarm message is used to remind the user that the vehicle can no longer provide the braking force to support the vehicle to decelerate or stop within the preset distance.

[0082] Among them, the preset braking force refers to the minimum braking force that the vehicle has within the braking demand. The braking demand is specified by combining safety requirements and user requirements, and the braking demand includes a preset distance. The preset distance is used to indicate the expected distance within which the vehicle can complete deceleration or stop.

[0083] In practical applications, considering that the driver cannot know how much the current braking force is, making the driving process not fully controllable, the current used braking intensity can be shown to the driver. In a possible implementation, after determining the current output air pressure corresponding to the current pedal depth according to the current pedal depth of the vehicle and the preset mapping relationship, the current braking intensity of the vehicle is determined according to the current output air pressure. Then, the current braking intensity and the maximum available braking force are displayed.

[0084] Among them, the preset mapping relationship is used to represent the corresponding relationship between the pedal depth and the output air pressure.

[0085] The output air pressure refers to the air outlet pressure of the valve body of the EBS after the driver steps on the brake pedal.

[0086] The current braking intensity refers to the braking intensity used by the vehicle under the current driving conditions. The current braking intensity includes the current braking force and the current braking acceleration.

[0087] It should be understood that the core idea of the EBS is to dynamically adjust the braking force of each axle according to the driver's demand, that is, the expected deceleration. A certain pedal depth corresponds to a certain deceleration. When the EBS detects that the current deceleration is lower than the driver's expected deceleration, the system will automatically increase the air pressure to provide a greater braking force until the expected deceleration is reached.

[0088] In a possible implementation, the currently used braking intensity and the maximum available braking intensity are displayed on the instrument in the form of numbers or progress bars, thus providing a good driving experience for the driver. At the same time, a reminder alarm is given when the remaining braking intensity is insufficient, and necessary water spraying for cooling or shutdown is carried out. Especially for autonomous driving vehicles lacking manual intervention, the braking performance state of the current vehicle can be obtained in real time and participate in communication.

[0089] In another possible implementation, the currently used braking intensity and the maximum available braking intensity participate in the vehicle communication in the form of messages and serve as the input of the AEBS system. When the maximum available braking intensity is small, automatic emergency braking needs to be intervened in advance. The maximum available braking intensity of the brake excluding the regenerative braking force can also be used as the input of the AEBS.

[0090] The maximum available braking force calculation method provided by the embodiments of the present application reflects the vehicle state by obtaining the regenerative braking force, the temperatures of the brakes on each axle, the air pressure in the air storage tank and the axle load of the vehicle. Then, the braking force of the brake is calculated by using the brake temperature and the air pressure in the air storage tank, thereby considering the synergistic effect of electric braking and air braking, and combining the regenerative braking force to obtain the braking capacity of the axle. Finally, the adhesion coefficient of the high-adhesion road surface and the axle load are used to evaluate the maximum available braking force of the whole vehicle in combination with the road surface state.

[0091] In practical applications, the maximum available braking force calculation method provided by the embodiments of the present application is not limited to electric heavy trucks and can be applied to vehicles using friction brakes and auxiliary brakes. This method is also applicable to oil vehicles, and the auxiliary brake is a hydraulic retarder, exhaust brake, etc. For electric vehicles, in addition to energy recovery, if there is resistive braking, it also needs to be calculated.

[0092] In addition, for new energy vehicles, a vehicle type with a regenerative braking system, since the braking method of this vehicle not only comes from traditional air braking or hydraulic braking, but also includes the regenerative braking force provided by the motor, the calculation of the available braking force of new energy vehicles is relatively complex. However, the maximum available braking force calculation method provided by the embodiments of the present application can dynamically optimize the distribution of regenerative braking and mechanical braking after calculating the maximum available braking force, which can not only maximize energy recovery to improve the cruising range, but also ensure the safety and stability of braking, thereby optimizing the overall performance and driving experience of new energy vehicles.

[0093] Figure 3 Flow schematic of the maximum available braking force calculation method provided by the embodiments of the present application Figure 2 as Figure 3 shown, the method includes:

[0094] S301. Obtain the air pressure in the air storage tank, the temperatures of the brakes on the axle, and the motor-executable negative torque;

[0095] S302. Calculate the regenerative braking force, the maximum available braking force, the maximum available braking intensity, and the currently used braking intensity;

[0096] S303. The instrument displays the maximum available braking intensity and the currently used braking intensity, and gives an alarm reminder according to the preset braking force;

[0097] S304. The maximum available braking intensity is used as the input of the AEBS. When the maximum available braking intensity is small, automatic emergency braking needs to be intervened in advance.

[0098] Figure 4 The structural schematic diagram of the maximum available braking force calculation device provided by the embodiment of the present application is as Figure 4 shown. The maximum available braking force calculation device 40 provided in this embodiment includes:

[0099] An acquisition module 401, configured to acquire the regenerative braking force of the vehicle, the brake temperature of each axle, the air storage tank air pressure, and the axle load;

[0100] A first determination module 402, configured to determine the braking capacity of each axle according to the regenerative braking force, the brake temperature of the axle, and the air storage tank air pressure for each axle;

[0101] A second determination module 403, configured to determine the maximum available braking force of the vehicle according to the preset adhesion coefficient, the axle load of each axle, and the braking capacity, and the preset adhesion coefficient is the adhesion coefficient corresponding to a high-adhesion road surface.

[0102] In a possible implementation manner, the first determination module 402 is further configured to, for each axle, determine the friction coefficient between the friction lining and the brake disc in the brake of the axle according to the brake temperature of the axle; determine the pressing force of the friction lining in the brake of the axle according to the air storage tank air pressure of the axle; determine the braking force of the brake of the axle according to the friction coefficient and the pressing force; and determine the braking capacity of each axle according to the regenerative braking force and the braking force of the brake of each axle.

[0103] In a possible implementation manner, the first determination module 402 is further configured to determine the braking force of the brake of the front axle as the braking capacity of the front axle; and determine the sum of the braking force of the brake of the rear axle and the regenerative braking force as the braking capacity of the rear axle.

[0104] In a possible implementation, the second determination module 403 is further configured to, for each axle, determine the maximum ground adhesion of the axle according to the axle load of the axle and a preset adhesion coefficient; determine the smaller value between the maximum ground adhesion and the braking capacity as the maximum available ground braking force of the axle; and determine the sum of the maximum available ground braking force of the front axle and the maximum available ground braking force of the rear axle as the maximum available braking force of the vehicle.

[0105] In a possible implementation, the acquisition module 401 is further configured to acquire the motor executable negative torque of the vehicle and determine the regenerative braking force of the vehicle.

[0106] In a possible implementation, the second determination module 403 is further configured to, if the maximum available braking force of the vehicle is less than a preset braking force, output an alarm message, where the alarm message is used to remind the user that the vehicle can no longer provide the braking force to support the vehicle to decelerate or stop within a preset distance.

[0107] In a possible implementation, the second determination module 403 is further configured to determine the current output air pressure corresponding to the current pedal depth according to the current pedal depth of the vehicle and a preset mapping relationship, where the preset mapping relationship is used to represent the corresponding relationship between the pedal depth and the output air pressure; determine the current braking intensity of the vehicle according to the current output air pressure; and display the current braking intensity and the maximum available braking force.

[0108] The maximum available braking force calculation device provided in this embodiment can execute the method provided in the above method embodiment, and its implementation principle and technical effect are similar, which will not be elaborated here in this embodiment.

[0109] Figure 5 It is a schematic structural diagram of an electronic device provided in an embodiment of the present application. As Figure 5 shown, the electronic device 50 provided in this embodiment includes: at least one processor 501 and a memory 502. Optionally, the electronic device 50 further includes a communication component 503. Among them, the processor 501, the memory 502, and the communication component 503 are connected through a bus 504.

[0110] In a specific implementation process, at least one processor 501 executes the computer execution instructions stored in the memory 502, so that at least one processor 501 executes the above method.

[0111] The specific implementation process of the processor 501 can refer to the above method embodiment, and its implementation principle and technical effect are similar, which will not be elaborated here in this embodiment.

[0112] In the above embodiments, it should be understood that the processor may be a central processing unit (CPU for short), or may also be other general-purpose processors, digital signal processors (DSP for short), application specific integrated circuits (ASIC for short), etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the method disclosed in combination with the invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules in the processor.

[0113] The memory may include a random access memory (RAM), and may also include a non-volatile memory (NVM), such as at least one disk memory.

[0114] The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, the buses in the drawings of this application are not limited to only one bus or one type of bus.

[0115] This application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0116] This application also provides a computer-readable storage medium, in which computer-executable instructions are stored, and when the processor executes the computer-executable instructions, the above method is implemented.

[0117] The above-readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as a static random access memory (SRAM), an electrically erasable programmable read-only memory (EEPROM), an erasable programmable read-only memory (EPROM), a programmable read-only memory (PROM), a read-only memory (ROM), a magnetic memory, a flash memory, a magnetic disk or an optical disk. The readable storage medium can be any available medium accessible by a general-purpose or special-purpose computer.

[0118] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can be located in an Application Specific Integrated Circuit (ASIC). Of course, the processor and the readable storage medium can also exist as discrete components in a device.

[0119] The division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Additionally, the couplings or direct couplings or communication connections shown or discussed between each other can be through some interfaces, and the indirect couplings or communication connections of devices or units can be in electrical, mechanical, or other forms.

[0120] The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0121] Furthermore, in each embodiment of the present invention, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0122] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or a part of this technical solution can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in each embodiment of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0123] Those of ordinary skill in the art will understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions. The foregoing program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments; and the foregoing storage medium includes: various media such as ROM, RAM, magnetic disk, or optical disk that can store program codes.

[0124] Finally, it should be noted that: after considering the specification and practicing the invention disclosed herein, those skilled in the art will readily conceive of other embodiments of the present invention. The present invention is intended to cover any variations, uses, or adaptations of the present invention, which follow the general principles of the present invention and include common general knowledge or conventional technical means in the technical field not disclosed in the present invention. It is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope.

Claims

1. A method for calculating the maximum available braking force, characterized in that, Including: Obtain the regenerative braking force of the vehicle, the brake temperature of each axle, the air pressure in the air reservoir, and the axle load; For each axle, determine the braking ability of the axle according to the regenerative braking force, the brake temperature of the axle, and the air pressure in the air reservoir; Determine the maximum available braking force of the vehicle according to a preset adhesion coefficient, the axle load of each axle, and the braking ability, where the preset adhesion coefficient is the adhesion coefficient corresponding to a high-adhesion road surface.

2. The method according to claim 1, wherein The step of, for each axle, determining the braking ability of the axle according to the regenerative braking force, the brake temperature of the axle, and the air pressure in the air reservoir includes: For each axle, determine the friction coefficient between the friction lining and the brake disc in the brake of the axle according to the brake temperature of the axle; Determine the pressing force of the friction lining in the brake of the axle according to the air pressure in the air reservoir of the axle; Determine the braking force of the brake of the axle according to the friction coefficient and the pressing force; Determine the braking ability of each axle according to the regenerative braking force and the braking force of the brake of each axle.

3. The method according to claim 2, wherein The step of determining the braking ability of each axle according to the regenerative braking force and the braking force of the brake of each axle includes: Determine the braking force of the brake of the front axle as the braking ability of the front axle; Determine the sum of the braking force of the brake of the rear axle and the regenerative braking force as the braking ability of the rear axle.

4. The method according to any one of claims 1-3, characterized in that, The step of determining the maximum available braking force of the vehicle according to a preset adhesion coefficient, the axle load of each axle, and the braking ability, where the preset adhesion coefficient is the adhesion coefficient corresponding to a high-adhesion road surface, includes: For each axle, determine the maximum ground adhesion of the axle according to the axle load of the axle and the preset adhesion coefficient; Determine the smaller value between the maximum ground adhesion and the braking ability as the maximum available ground braking force of the axle; Determine the sum of the maximum available ground braking force of the front axle and the maximum available ground braking force of the rear axle as the maximum available braking force of the vehicle.

5. The method according to any one of claims 1-3, characterized in that, The step of obtaining the regenerative braking force of the vehicle includes: Obtain the negative torque that the motor of the vehicle can execute, and determine the regenerative braking force of the vehicle.

6. The method according to any one of claims 1-3, characterized in that, The method further includes: If the maximum available braking force of the vehicle is less than a preset braking force, output an alarm message, where the alarm message is used to remind the user that the vehicle can no longer provide the braking force to support the vehicle to decelerate or stop within a preset distance.

7. The method according to any one of claims 1 to 3, characterized in that The method further includes: Determine the current output air pressure corresponding to the current pedal depth according to the current pedal depth of the vehicle and a preset mapping relationship, where the preset mapping relationship is used to represent the corresponding relationship between the pedal depth and the output air pressure; Determine the current braking intensity of the vehicle according to the current output air pressure; Display the current braking intensity and the maximum available braking force.

8. A maximum available braking force calculation device, characterized in that, Including: An acquisition module, configured to obtain the regenerative braking force of the vehicle, the brake temperature of each axle, the air pressure in the air reservoir, and the axle load; A first determination module, configured to, for each axle, determine the braking ability of the axle according to the regenerative braking force, the brake temperature of the axle, and the air pressure in the air reservoir; A second determination module, configured to determine the maximum available braking force of the vehicle according to a preset adhesion coefficient, the axle load of each axle, and the braking ability, where the preset adhesion coefficient is the adhesion coefficient corresponding to a high-adhesion road surface.

9. An electronic device, characterized in that, Comprising: A memory and a processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the processor executes the method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, Computer-executable instructions are stored in the computer-readable storage medium, and when the computer-executable instructions are executed by a processor, they are used to implement the method according to any one of claims 1-7.

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