Vehicle brake force distribution method, device, controller and storage medium

Abstract

This invention provides a vehicle braking force distribution method, device, controller, and storage medium. The method includes: acquiring the braking signal from the vehicle's brake pedal to obtain the vehicle's total braking force; if it is determined that the vehicle's current speed is greater than the minimum speed required to trigger regenerative braking, calculating the vehicle's rear axle braking force; if a tendency for the vehicle's front wheels to lock up is detected, setting the vehicle's front axle braking force as the critical braking force required for front axle lockup; if it is determined that the rear axle braking force is greater than the maximum allowable regenerative braking force of the rear axle, setting the mechanical braking force of the rear axle as the difference between the rear axle braking force and the maximum allowable regenerative braking force of the rear axle, and setting the regenerative braking force of the rear axle as the maximum allowable regenerative braking force of the rear axle; if a tendency for the vehicle's rear wheels to lock up is detected, setting the vehicle's rear axle braking force as the critical braking force required for rear axle lockup. This invention maximizes the utilization of regenerative braking force and achieves optimal braking performance through braking force distribution.

Description

Technical Field

[0001] This invention relates to the field of electric vehicle braking technology, and in particular to a vehicle braking force distribution method, device, controller and storage medium. Background Technology

[0002] The regenerative braking system (RBS) of a car can recover and utilize a portion of the vehicle's braking energy during braking, thereby improving the efficiency of braking energy utilization.

[0003] Currently, vehicle braking generally employs the following strategy: when a tendency for the wheels to lock up is detected, regenerative braking force is quickly disengaged, and the system switches to the traditional mechanical braking system for adjustment of the Anti-lock Braking System (ABS).

[0004] However, existing strategies have the following problems: low energy recovery efficiency of vehicles and inability to achieve optimal braking performance. Summary of the Invention

[0005] This invention provides a vehicle braking force distribution method, device, controller, and storage medium to solve the problem of low energy recovery and utilization rate and inability to achieve optimal braking effect in vehicles in the prior art.

[0006] In a first aspect, the present invention provides a vehicle braking force distribution method, applied to a vehicle controller of an electric vehicle, the method comprising:

[0007] Obtain the braking signal from the vehicle's brake pedal, and calculate the vehicle's total braking force based on the braking signal;

[0008] If it is determined that the current driving speed of the vehicle is greater than the minimum speed at which regenerative braking is triggered, then the rear axle braking force of the vehicle is determined based on the total braking force and the I curve; wherein, the I curve is the relationship curve that the front axle braking force and the rear axle braking force should satisfy in order for the front and rear wheels of the vehicle to lock simultaneously when the vehicle is braking, and the I curve is obtained by force analysis calculation of the vehicle during braking.

[0009] Determine the critical braking force required for front axle lock-up, the maximum permissible regenerative braking force for rear axle, and the critical braking force required for rear axle lock-up.

[0010] If a tendency for the front wheels of the vehicle to lock up is detected, the braking force of the front axle of the vehicle is set to the critical braking force required for front axle lockup.

[0011] If it is determined that the rear axle braking force is greater than the maximum allowable regenerative braking force of the rear axle, then the mechanical braking force of the vehicle's rear axle is set to the difference between the rear axle braking force and the maximum allowable regenerative braking force of the rear axle, and the regenerative braking force of the vehicle's rear axle is set to the maximum allowable regenerative braking force of the rear axle.

[0012] If a tendency for the rear wheels of the vehicle to lock up is detected, the braking force of the rear axle of the vehicle is set to the critical braking force required for rear axle lockup.

[0013] In one possible design, acquiring the braking signal from the vehicle's brake pedal and obtaining the vehicle's total braking force based on the braking signal includes: acquiring the vehicle's braking signal and obtaining the braking deceleration based on the braking signal; receiving identification data sent by the vehicle's road surface recognition device, load recognition device, and slope recognition device; and calculating the vehicle's total braking force based on the braking deceleration and the identification data.

[0014] In one possible design, calculating the rear axle braking force of the vehicle based on the total braking force and the I-curve includes: if the target deceleration of the vehicle is detected to be less than a first deceleration, then determining that the rear axle braking force is the maximum allowable regenerative braking force of the rear axle, which increases from zero as the brake pedal opening increases; wherein, the first deceleration is the deceleration of the vehicle when it is fully utilizing the maximum regenerative braking force, and the maximum regenerative braking force is obtained through calibration; if the target deceleration of the vehicle is detected to be greater than the first deceleration and less than a second deceleration, then determining that the rear axle braking force is the maximum allowable regenerative braking force of the rear axle; wherein, the second deceleration is the deceleration of the vehicle when the distribution of the front axle braking force and the rear axle braking force reaches the I-curve; if the target deceleration is detected to be greater than the second deceleration, then distributing the total braking force based on the I-curve to obtain the rear axle braking force.

[0015] In one possible design, after obtaining the total braking force of the vehicle based on the braking signal, the method further includes: if it is determined that the vehicle speed is less than or equal to the minimum speed at which the regenerative braking is triggered, then mechanical braking of the vehicle's electromechanical braking system is executed.

[0016] In one possible design, the method further includes: if it is determined that the rear axle braking force is less than or equal to the maximum allowable regenerative braking force of the rear axle, then regenerative braking of the vehicle's regenerative braking energy recovery system is performed; if a tendency for the rear wheels of the vehicle to lock up is detected, then the rear axle braking force of the vehicle is set to the critical lock-up requirement braking force of the rear axle.

[0017] In one possible design, after setting the rear axle braking force of the vehicle to the critical braking force required for rear axle lock-up, the method further includes: if it is determined that the critical braking force required for rear axle lock-up is greater than or equal to the maximum allowable regenerative braking force of the rear axle, then setting the regenerative braking force of the vehicle's rear axle to the maximum allowable regenerative braking force of the rear axle, and setting the mechanical braking force of the vehicle's rear axle to the difference between the critical braking force required for rear axle lock-up and the maximum allowable regenerative braking force of the rear axle; if it is determined that the critical braking force required for rear axle lock-up is less than the maximum allowable regenerative braking force of the rear axle, then determining the regenerative braking force used when the rear wheels of the vehicle are critically locked-up, and setting the regenerative braking force of the vehicle's rear axle to the regenerative braking force used when the rear wheels are critically locked-up.

[0018] Secondly, the present invention provides a vehicle braking force distribution device, comprising: an acquisition module, configured to acquire a braking signal from a vehicle's brake pedal and obtain the vehicle's total braking force based on the braking signal; a first determination module, configured to determine the vehicle's rear axle braking force based on the total braking force and an I-curve if it is determined that the vehicle's current driving speed is greater than the minimum speed required to trigger regenerative braking; wherein the I-curve is a relationship curve that the front axle braking force and the rear axle braking force must satisfy to simultaneously lock the front and rear wheels of the vehicle during braking, and the I-curve is obtained by force analysis calculation of the vehicle during braking; and a second determination module, configured to determine the critical braking force required for front axle lockup and the rear axle braking force. The system includes: a maximum permissible regenerative braking force for the front axle and a critical braking force required for rear axle lockup; a first setting module, configured to set the braking force of the front axle to the critical braking force required for front axle lockup if a tendency for the front wheels of the vehicle to lock up is detected; a second setting module, configured to set the mechanical braking force of the rear axle of the vehicle to the difference between the rear axle braking force and the maximum permissible regenerative braking force for the rear axle, and set the regenerative braking force of the rear axle to the maximum permissible regenerative braking force for the rear axle, if the rear axle braking force is determined to be greater than the maximum permissible regenerative braking force for the rear axle; and a third setting module, configured to set the braking force of the rear axle of the vehicle to the critical braking force required for rear axle lockup if a tendency for the rear wheels of the vehicle to lock up is detected.

[0019] Thirdly, the present invention provides a vehicle controller, comprising: at least one processor and a memory; the memory storing computer-executable instructions; the at least one processor executing the computer-executable instructions stored in the memory, such that the at least one processor performs the method described in the first aspect above and various possible designs of the first aspect.

[0020] Fourthly, the present invention provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the methods described in accordance with the first aspect above and various possible designs of the first aspect.

[0021] Fifthly, the present invention provides a computer program product comprising a computer program that, when executed by a processor, implements the method described in accordance with the first aspect above and various possible designs of the first aspect.

[0022] The vehicle braking force distribution method, device, controller, and storage medium provided in this application acquire the braking signal from the vehicle's brake pedal and obtain the vehicle's total braking force based on the braking signal; determine the critical braking force required for front axle lock-up, the maximum allowable regenerative braking force for rear axle, and the critical braking force required for rear axle lock-up; if it is determined that the vehicle's current driving speed is greater than the minimum speed for triggering regenerative braking, the front axle braking force and rear axle braking force are calculated based on the total braking force and the I-curve; if a tendency for the vehicle's front wheels to lock up is detected, the front axle braking force is set as the critical braking force required for front axle lock-up; if it is determined that the rear axle braking force is greater than the maximum allowable regenerative braking force for rear axle, the mechanical braking force of the vehicle's rear axle is set as the difference between the rear axle braking force and the maximum allowable regenerative braking force for rear axle, and the regenerative braking force of the vehicle's rear axle is set as the maximum allowable regenerative braking force for rear axle; if a tendency for the vehicle's rear wheels to lock up is detected, the rear axle braking force is set as the critical braking force required for rear axle lock-up, thereby maximizing the utilization of regenerative braking force and achieving optimal braking effect through braking force distribution. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A schematic flowchart of the vehicle braking force distribution method provided in an embodiment of the present invention. Figure 1 ;

[0025] Figure 2 A schematic flowchart of the vehicle braking force distribution method provided in an embodiment of the present invention. Figure 2 ;

[0026] Figure 3 A schematic flowchart of the vehicle braking force distribution method provided in an embodiment of the present invention. Figure 3 ;

[0027] Figure 4 A schematic diagram illustrating the distribution of front axle braking force and rear axle braking force according to an embodiment of the present invention;

[0028] Figure 5This is a schematic diagram of the structure of the vehicle braking force distribution device provided in an embodiment of the present invention;

[0029] Figure 6 This is a schematic diagram of the structure of a vehicle controller provided in an embodiment of the present invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Regenerative braking energy recovery systems in automobiles recover and utilize a portion of the vehicle's braking energy during braking, thereby improving braking energy efficiency. Currently, vehicle braking generally employs the following strategy: when a tendency for wheels to lock up is detected, regenerative braking force is quickly disengaged, switching to the conventional mechanical braking system for anti-lock braking system (ABS) adjustment. However, existing strategies suffer from the following problems: low energy recovery efficiency and inability to achieve optimal braking performance.

[0032] To solve the above-mentioned technical problems, the embodiments of the present invention propose the following technical solution: by giving priority to the use of regenerative braking force during the braking process, and then using mechanical braking force according to certain rules when the regenerative braking force is insufficient, the regenerative braking force is maximized and the best braking effect is achieved through the distribution of braking force.

[0033] The following detailed embodiments will be used to illustrate the point.

[0034] Figure 1 A schematic flowchart of the vehicle braking force distribution method provided in an embodiment of the present invention. Figure 1 In this embodiment, the executing entity can be the vehicle controller of an electric vehicle, wherein the electric vehicle can be a front-wheel drive, rear-wheel drive, or four-wheel drive electric vehicle. The vehicle controller can implement the following methods through software, hardware, or a combination of software and hardware; this embodiment does not impose any particular limitations. Figure 1 As shown, the method includes:

[0035] S101: Obtain the braking signal from the vehicle's brake pedal and calculate the vehicle's total braking force based on the braking signal.

[0036] In this embodiment, the specific steps for obtaining the braking signal from the vehicle's brake pedal and calculating the vehicle's total braking force based on the braking signal include:

[0037] The system acquires the vehicle's braking signal and calculates the braking deceleration based on the signal; it receives identification data from the vehicle's road surface recognition device, load recognition device, and slope recognition device; and it calculates the vehicle's total braking force based on the braking deceleration and identification data.

[0038] Specifically, the Electromechanical Brake (EMB) system calculates the driver's expected braking deceleration based on the brake pedal opening, and then calculates the total braking force based on identification data from the road surface recognition device, load recognition device, and slope recognition device. Gear shifting is not allowed during braking.

[0039] S102: Determine the critical braking force required for front axle lock-up, the maximum permissible regenerative braking force for rear axle, and the critical braking force required for rear axle lock-up.

[0040] In this embodiment, the critical braking force required for front axle lock-up, the maximum allowable regenerative braking force for rear axle, and the critical braking force required for rear axle lock-up are determined by the vehicle controller. The maximum allowable regenerative braking force for rear axle is affected by factors such as battery state of charge (SOC) and motor speed. If energy recovery is not allowed, mechanical braking is used directly, and the braking forces of the front and rear axles are distributed according to the I-curve. Battery state of charge (SOC) reflects the remaining capacity of the battery and is numerically defined as the ratio of remaining capacity to battery capacity. Lock-up refers to the brake clamping the tire, with no relative movement between the tire and the brake, meaning the tire no longer rotates.

[0041] Specifically, the regenerative braking energy recovery in this embodiment includes coasting energy recovery and braking energy recovery.

[0042] S103: Determine whether the vehicle's current speed is greater than the minimum speed required to trigger regenerative braking. If so, proceed to step S104.

[0043] In this embodiment, the minimum vehicle speed for triggering regenerative braking is generally 10km / h to 15km / h.

[0044] S104: The rear axle braking force of the vehicle is calculated based on the total braking force and the I curve. The I curve is the relationship curve that the front axle braking force and the rear axle braking force should satisfy in order for the front and rear wheels of the vehicle to lock simultaneously when the vehicle is braking. The I curve is obtained by performing force analysis calculations on the vehicle during braking.

[0045] Specifically, the I-curve is an ideal front and rear brake force distribution curve. The goal is that if the front and rear wheels lock up, the lockup should occur simultaneously, rather than one after the other, to maximize the utilization of traction. In other words, the I-curve refers to the relationship between the front and rear wheel braking forces required to achieve simultaneous lockup of the front and rear wheels when braking on road surfaces with various coefficients of adhesion. This curve can be obtained by performing force analysis on the vehicle during braking.

[0046] Figure 4 This is a schematic diagram illustrating the distribution of front axle braking force and rear axle braking force according to an embodiment of the present invention. Figure 4 The diagram showing the distribution of front axle braking force and rear axle braking force is applicable to two-axle rear-wheel drive vehicles. Figure 4 The horizontal axis represents the magnitude of the front axle braking force, and the vertical axis represents the magnitude of the rear axle braking force. From Figure 4 As can be seen from the I curve, the I curve is not linear. As the braking intensity increases, the increase in front axle braking force is greater than that in rear axle braking force. This is because as the braking intensity increases, the normal reaction force of the ground on the front wheel increases, while the normal reaction force on the rear wheel decreases. The specific calculation process of the I curve can be carried out according to the existing calculation methods in the prior art.

[0047] In this embodiment, the front and rear axle braking forces of the vehicle are calculated based on the total braking force and the I-curve, and must meet the requirements of the ECE regulations, where ECE is the abbreviation for the United Nations Economic Commission for Europe's automotive regulations. To ensure the safety and stability of vehicle deceleration and braking, the distribution of front and rear axle braking forces during the vehicle's combined braking phase must meet the requirements of the ECE regulations.

[0048] S105: Detect whether the front wheels of the vehicle are prone to locking up. If so, proceed to step S106.

[0049] In this embodiment, the vehicle braking force distribution method of this application has an anti-lock braking function. When a tendency for the wheel to lock up is detected, the regenerative braking system is not disengaged, and the regenerative braking system works in conjunction with the mechanical braking and the vehicle anti-lock braking system to control the slip ratio near the optimal value.

[0050] S106: Set the front axle braking force of the vehicle to the critical braking force required for front axle lockup.

[0051] In this embodiment, when a tendency for the front wheels to lock up is detected, the braking force of the vehicle's front axle is set to the critical braking force required for front axle lockup. This allows the vehicle to achieve reliable braking while avoiding the dangerous condition of wheel lockup, thereby improving the vehicle's braking safety.

[0052] S107: Determine whether the rear axle braking force is greater than the maximum allowable regenerative braking force of the rear axle. If so, proceed to step S108.

[0053] S108: Set the mechanical braking force of the rear axle of the vehicle to the difference between the rear axle braking force and the maximum permissible regenerative braking force of the rear axle, and set the regenerative braking force of the rear axle of the vehicle to the maximum permissible regenerative braking force of the rear axle.

[0054] In this embodiment, when the rear axle braking force is greater than the maximum allowable regenerative braking force of the rear axle, the braking force allocated to the rear axle of the vehicle includes two parts: mechanical braking force and regenerative braking force. The magnitude of the mechanical braking force is the difference between the rear axle braking force and the maximum allowable regenerative braking force of the rear axle, and the magnitude of the regenerative braking force is the maximum allowable regenerative braking force of the rear axle.

[0055] Specifically, whether the regenerative braking system provides braking force alone or in conjunction with the mechanical braking system, it must meet the driver's total braking force requirements to ensure braking efficiency.

[0056] S109: Detect whether the rear wheels of the vehicle are prone to locking up. If so, proceed to step S110.

[0057] In this embodiment, the vehicle braking force distribution method of this application has an anti-lock braking function. When a tendency for the wheel to lock up is detected, the regenerative braking system is not disengaged, and the regenerative braking system works in conjunction with the mechanical braking and the vehicle anti-lock braking system to control the slip ratio near the optimal value.

[0058] Specifically, the braking force distribution strategy for the rear-wheel anti-lock braking system (ABS) is as follows: The activation threshold of the ABS continues to follow the existing road surface recognition and activation thresholds. Based on the wheel speeds and vehicle speed, the ABS determines the vehicle's slip ratio. When the driver continuously increases braking force and the wheels reach the ideal slip ratio control area, the braking force is no longer increased, and the ABS achieves a pressure-maintaining function, keeping the slip ratio at the optimal wheel slip ratio to maximize ground adhesion. If the vehicle's drive wheels (rear wheels) are on the contact surface, the maximum regenerative braking value is determined based on the maximum braking force required to avoid locking on the low-traction surface. When the drive wheels (rear wheels) move from a high-traction surface to a low-traction surface, the vehicle needs to lock momentarily. The EMB system needs to quickly "depressurize" and readjust the braking force required to identify the ideal slip ratio on the low-traction surface. During depressurization, the priority is given to reducing mechanical braking force, followed by reducing regenerative braking force. When the drive wheels (rear wheels) move from a low-traction surface to a high-traction surface, the braking force needs to be compensated quickly. This means the EMB system needs to rapidly "boost" the braking force required for the ideal slip ratio on the high-traction surface and the driver's braking force demand. During the boosting process, the regenerative braking force is used first, followed by the mechanical braking force.

[0059] S110: Set the rear axle braking force of the vehicle to the critical braking force required for rear axle lockup.

[0060] In this embodiment, when a tendency for the rear wheels of the vehicle to lock up is detected, the braking force of the rear axle of the vehicle is set to the critical braking force required for rear axle lockup. This allows the vehicle to achieve reliable braking while avoiding the dangerous condition of wheel lockup, thereby improving the braking safety of the vehicle.

[0061] In summary, the vehicle braking force distribution method provided in this embodiment obtains the braking signal from the vehicle's brake pedal and calculates the vehicle's total braking force based on the braking signal; it determines the critical braking force required for front axle lock-up, the maximum allowable regenerative braking force for rear axle, and the critical braking force required for rear axle lock-up; if it is determined that the vehicle's current speed is greater than the minimum speed required to trigger regenerative braking, the front axle braking force and rear axle braking force are calculated based on the total braking force and the I-curve; if a tendency for the vehicle's front wheels to lock up is detected, the front axle braking force is set as the critical braking force required for front axle lock-up; if it is determined that the rear axle braking force is greater than the maximum allowable regenerative braking force for rear axle, the mechanical braking force of the vehicle's rear axle is set as the difference between the rear axle braking force and the maximum allowable regenerative braking force for rear axle, and the regenerative braking force of the vehicle's rear axle is set as the maximum allowable regenerative braking force for rear axle; if a tendency for the vehicle's rear wheels to lock up is detected, the rear axle braking force is set as the critical braking force required for rear axle lock-up. This maximizes the utilization of regenerative braking force and achieves optimal braking performance through braking force distribution.

[0062] Figure 2 A schematic flowchart of the vehicle braking force distribution method provided in an embodiment of the present invention. Figure 2 In this embodiment of the invention, the specific implementation method for calculating the front axle braking force and rear axle braking force of the vehicle based on the total braking force and the I curve in step S104 is described in detail. For example... Figure 2 As shown, the method includes:

[0063] S201: If the target deceleration of the vehicle is detected to be less than the first deceleration, the rear axle braking force is determined to increase from zero to the maximum allowable regenerative braking force of the rear axle as the brake pedal opening increases; wherein, the first deceleration is the deceleration of the vehicle when the maximum regenerative braking force is fully used, and the maximum regenerative braking force is obtained through calibration.

[0064] In this embodiment, the maximum regenerative braking torque of the vehicle is obtained through calibration, and the maximum regenerative braking force is calculated based on the maximum regenerative braking torque. This is used to determine the first deceleration of the vehicle when it fully utilizes the maximum regenerative braking force.

[0065] Specifically, Figure 4 This is a schematic diagram illustrating the distribution of front axle braking force and rear axle braking force according to an embodiment of the present invention. Figure 4 The horizontal axis represents the magnitude of the front axle braking force, and the vertical axis represents the magnitude of the rear axle braking force. Figure 4As can be seen, if the target deceleration of the vehicle is less than the first deceleration, as the brake pedal opening increases, the front axle braking force is 0, while the rear axle braking force increases from zero to the maximum allowable regenerative braking force of the rear axle as the brake pedal opening increases.

[0066] S202: If the target deceleration of the vehicle is detected to be greater than the first deceleration and less than the second deceleration, then the rear axle braking force is determined to be the maximum allowable regenerative braking force of the rear axle; wherein, the second deceleration is the deceleration of the vehicle when the distribution of the front axle braking force and the rear axle braking force reaches the I curve.

[0067] In this embodiment, when the rear wheel reaches the maximum regenerative braking force, as the brake pedal opening continues to increase, the maximum regenerative braking force of the rear wheel remains unchanged, and mechanical braking is applied to the front wheel, so that the distribution of braking force between the front axle and the rear axle gradually approaches the I curve. When the I curve is about to be reached, the deceleration of the vehicle is the second deceleration.

[0068] Specifically, from Figure 4 As can be seen, if the target deceleration of the vehicle is greater than the first deceleration and less than the second deceleration, as the brake pedal opening continues to increase, the front axle braking force is the mechanical braking force applied to the front axle, while the rear axle braking force remains unchanged at the maximum allowable regenerative braking force of the rear axle.

[0069] S203: If the target deceleration is detected to be greater than the second deceleration, the total braking force will be distributed based on the I curve to obtain the rear axle braking force.

[0070] In this embodiment, when the target deceleration is greater than the second deceleration, the distribution of the front axle braking force and the rear axle braking force is based on the I curve, and the sum of the front axle braking force and the rear axle braking force is the total braking force of the vehicle.

[0071] Specifically, from Figure 4 As can be seen from this, if the target deceleration of the vehicle is greater than the second deceleration, the distribution of the front axle braking force and the rear axle braking force is based on the I curve.

[0072] In summary, the vehicle braking force distribution method provided in this embodiment determines the rear axle braking force to be the maximum allowable regenerative braking force of the rear axle as the brake pedal opening increases from zero if the target deceleration of the vehicle is detected to be less than the first deceleration; if the target deceleration of the vehicle is detected to be greater than the first deceleration but less than the second deceleration, the rear axle braking force is determined to be the maximum allowable regenerative braking force of the rear axle; if the target deceleration is detected to be greater than the second deceleration, the total braking force is distributed based on the I curve to obtain the rear axle braking force, thus realizing the distribution of front axle braking force and rear axle braking force based on the maximum energy principle.

[0073] Figure 3 A schematic flowchart of the vehicle braking force distribution method provided in an embodiment of the present invention. Figure 3 The embodiment is a practical implementation of the vehicle braking force distribution method. For example... Figure 3 As shown, the method includes:

[0074] S301: Obtain the braking signal from the vehicle's brake pedal and calculate the vehicle's total braking force based on the braking signal.

[0075] S302: Determine the critical braking force required for front axle lock-up, the maximum permissible regenerative braking force for rear axle, and the critical braking force required for rear axle lock-up.

[0076] S303: Determine whether the vehicle's current speed is greater than the minimum speed required to trigger regenerative braking. If yes, proceed to step S304; otherwise, proceed to step S305.

[0077] S304: The rear axle braking force of the vehicle is calculated based on the total braking force and the I curve. The I curve is the relationship curve that the front axle braking force and the rear axle braking force should satisfy in order for the front and rear wheels of the vehicle to lock simultaneously when the vehicle is braking. The I curve is obtained by performing force analysis calculations on the vehicle during braking.

[0078] S305: Mechanical braking that activates the vehicle’s electromechanical braking system.

[0079] In this embodiment, when the vehicle speed is less than or equal to the minimum speed at which regenerative braking is triggered, regenerative braking is discontinued or not initiated, and thus mechanical braking of the vehicle's electromechanical braking system is performed.

[0080] S306: Detect whether the front wheels of the vehicle are prone to locking up. If yes, proceed to step S307; otherwise, proceed to step S308.

[0081] S307: Set the front axle braking force of the vehicle to the critical braking force required for front axle lockup.

[0082] S308: Keep the front axle braking force of the vehicle unchanged.

[0083] In this embodiment, if the front wheels of the vehicle do not tend to lock up, the vehicle can achieve safe braking and will not experience the dangerous condition of locking up. It is sufficient to keep the braking force of the front axle of the vehicle unchanged.

[0084] S309: Determine whether the rear axle braking force is greater than the maximum allowable regenerative braking force of the rear axle. If yes, proceed to step S310; otherwise, proceed to step S311.

[0085] S310: Set the mechanical braking force of the rear axle of the vehicle to the difference between the rear axle braking force and the maximum permissible regenerative braking force of the rear axle, and set the regenerative braking force of the rear axle of the vehicle to the maximum permissible regenerative braking force of the rear axle.

[0086] S311: Regenerative braking is performed by the vehicle's regenerative braking energy recovery system.

[0087] In this embodiment, if the rear axle braking force is less than or equal to the maximum allowable regenerative braking force of the rear axle, the regenerative braking force is used first. If the regenerative braking force is insufficient, the mechanical braking force is used according to certain rules. Therefore, the regenerative braking of the vehicle's regenerative braking energy recovery system is performed at this time.

[0088] S312: Detect whether the rear wheels of the vehicle are prone to locking up. If yes, proceed to step S313; otherwise, proceed to step S314.

[0089] S313: Set the braking force of the vehicle's rear axle to the critical braking force required for rear axle lockup.

[0090] S314: Keep the rear axle braking force of the vehicle constant.

[0091] In this embodiment, if the rear wheels of the vehicle do not tend to lock up, the vehicle can achieve safe braking and will not experience the dangerous situation of locking up. The braking force on the rear axle of the vehicle can be kept constant.

[0092] S315: Determine whether the critical braking force required for rear axle lock-up is greater than or equal to the maximum allowable regenerative braking force of the rear axle. If yes, proceed to step S316; otherwise, proceed to step S317.

[0093] S316: Set the regenerative braking force of the rear axle of the vehicle to the maximum allowable regenerative braking force of the rear axle, and set the mechanical braking force of the rear axle of the vehicle to the difference between the critical lock-up braking force of the rear axle and the maximum allowable regenerative braking force of the rear axle.

[0094] In this embodiment, the critical braking force required for rear axle lock-up is greater than or equal to the maximum allowable regenerative braking force of the rear axle. At this point, the regenerative braking system alone cannot meet the critical braking force requirement for rear axle lock-up; therefore, supplementary mechanical braking force is needed. Thus, the regenerative braking force of the vehicle's rear axle is set to the maximum allowable regenerative braking force, and the mechanical braking force of the vehicle's rear axle is set to the difference between the critical braking force required for rear axle lock-up and the maximum allowable regenerative braking force. The regenerative braking force and mechanical braking force work together to meet the critical braking force requirement for rear axle lock-up, ensuring braking performance.

[0095] S317: Determine the regenerative braking force used when the rear wheels of the vehicle are on the verge of locking up, and set the regenerative braking force of the rear axle of the vehicle to the regenerative braking force used when the rear wheels are on the verge of locking up.

[0096] In this embodiment, the braking force required for the rear axle to critically lock up is less than the maximum allowable regenerative braking force of the rear axle. In this case, the regenerative braking system alone is sufficient to meet the braking force requirement for the rear axle to critically lock up, without the need for additional mechanical braking force. Therefore, the regenerative braking force used when the rear wheels of the vehicle are critically locked up is first determined, and the regenerative braking force of the vehicle's rear axle is set to the regenerative braking force used when the rear wheels are critically locked up.

[0097] In summary, the vehicle braking force distribution method provided in this embodiment obtains the braking signal from the vehicle's brake pedal and calculates the vehicle's total braking force based on the braking signal; it determines the critical braking force required for front axle lock-up, the maximum allowable regenerative braking force for rear axle, and the critical braking force required for rear axle lock-up; if it is determined that the vehicle's current speed is greater than the minimum speed required to trigger regenerative braking, the front axle braking force and rear axle braking force are calculated based on the total braking force and the I-curve; if a tendency for the vehicle's front wheels to lock up is detected, the front axle braking force is set as the critical braking force required for front axle lock-up; if it is determined that the rear axle braking force is greater than the maximum allowable regenerative braking force for rear axle, the mechanical braking force of the vehicle's rear axle is set as the difference between the rear axle braking force and the maximum allowable regenerative braking force for rear axle, and the regenerative braking force of the vehicle's rear axle is set as the maximum allowable regenerative braking force for rear axle; if a tendency for the vehicle's rear wheels to lock up is detected, the rear axle braking force is set as the critical braking force required for rear axle lock-up. During braking, regenerative braking force is used first. When the regenerative braking force is insufficient, mechanical braking force is used according to certain rules to maximize the utilization of regenerative braking force and achieve the best braking effect through braking force distribution.

[0098] Figure 5 This is a schematic diagram of the vehicle braking force distribution device provided in an embodiment of the present invention. Figure 5 As shown, the vehicle braking force distribution device includes: an acquisition module 501, a first determination module 502, a second determination module 503, a first setting module 504, a second setting module 505, and a third setting module 506.

[0099] The acquisition module 501 is used to acquire the braking signal from the vehicle's brake pedal and obtain the total braking force of the vehicle based on the braking signal.

[0100] The first determination 502 is used to determine the critical braking force required for front axle lock-up, the maximum permissible regenerative braking force for rear axle, and the critical braking force required for rear axle lock-up.

[0101] The second determining module 503 is used to determine the rear axle braking force of the vehicle based on the total braking force and the I curve if it is determined that the current driving speed of the vehicle is greater than the minimum vehicle speed for triggering regenerative braking. The I curve is the relationship curve that the front axle braking force and the rear axle braking force should satisfy in order for the front and rear wheels of the vehicle to lock up simultaneously when the vehicle is braking. The I curve is obtained by performing force analysis calculations on the vehicle during braking.

[0102] The first setting module 505 is used to set the front axle braking force of the vehicle to the critical front axle lock-up braking force if a tendency to lock up the front wheels of the vehicle is detected.

[0103] The second setting module 505 is used to set the mechanical braking force of the vehicle's rear axle to the difference between the rear axle braking force and the maximum allowable regenerative braking force of the rear axle if it is determined that the rear axle braking force is greater than the maximum allowable regenerative braking force of the rear axle, and to set the regenerative braking force of the vehicle's rear axle to the maximum allowable regenerative braking force of the rear axle.

[0104] The third setting module 506 is used to set the vehicle's rear axle braking force to the critical braking force required for rear axle lockup if a tendency for the rear wheels of the vehicle to lock up is detected.

[0105] In one possible implementation, the acquisition module 501 is specifically used to acquire the vehicle's braking signal, obtain the braking deceleration based on the braking signal, receive identification data sent by the vehicle's road surface identification device, load identification device, and slope identification device, and calculate the vehicle's total braking force based on the braking deceleration and the identification data.

[0106] In one possible implementation, the calculation module 502 is specifically used to: if the target deceleration of the vehicle is detected to be less than a first deceleration, determine the rear axle braking force as the brake pedal opening increases from zero to the maximum allowable regenerative braking force of the rear axle; wherein, the first deceleration is the deceleration of the vehicle when the maximum regenerative braking force is fully utilized, and the maximum regenerative braking force is obtained through calibration; if the target deceleration of the vehicle is detected to be greater than the first deceleration and less than a second deceleration, determine the rear axle braking force as the maximum allowable regenerative braking force of the rear axle; wherein, the second deceleration is the deceleration of the vehicle when the distribution of the front axle braking force and the rear axle braking force reaches the I curve; if the target deceleration is detected to be greater than the second deceleration, distribute the total braking force based on the I curve to obtain the rear axle braking force.

[0107] In one possible implementation, the vehicle braking force distribution device further includes: a first execution module 507, used to execute mechanical braking of the vehicle's electromechanical braking system if it is determined that the vehicle speed is less than or equal to the minimum speed at which regenerative braking is triggered.

[0108] In one possible implementation, the vehicle braking force distribution device further includes: a first execution module 508, used to execute regenerative braking of the vehicle's regenerative braking energy recovery system if it is determined that the rear axle braking force is less than or equal to the maximum allowable regenerative braking force of the rear axle; and to set the vehicle's rear axle braking force to the critical rear axle lock-up requirement braking force if it is detected that the rear wheels of the vehicle are prone to lock-up.

[0109] In one possible implementation, the vehicle braking force distribution device further includes: a fourth setting module 509, configured to, if it is determined that the critical braking force required for rear axle lock-up is greater than or equal to the maximum allowable regenerative braking force of the rear axle, set the regenerative braking force of the vehicle's rear axle to the maximum allowable regenerative braking force of the rear axle, and set the mechanical braking force of the vehicle's rear axle to the difference between the critical braking force required for rear axle lock-up and the maximum allowable regenerative braking force of the rear axle; and if it is determined that the critical braking force required for rear axle lock-up is less than the maximum allowable regenerative braking force of the rear axle, determine the regenerative braking force to be used when the rear wheels of the vehicle are critically locked-up, and set the regenerative braking force of the vehicle's rear axle to the regenerative braking force to be used when the rear wheels are critically locked-up.

[0110] The vehicle braking force distribution device provided in this application embodiment can be used to execute the technical solution of the vehicle braking force distribution method in the above embodiment. Its implementation principle and technical effect are similar, and will not be described again here.

[0111] It should be noted that the division of the various modules in the above device is merely a logical functional division. In actual implementation, they can be fully or partially integrated into a single physical entity, or they can be physically separated. Furthermore, these modules can be implemented entirely in software via processing element calls; they can be fully implemented in hardware; or some modules can be implemented by processing element calls to software, while others are implemented in hardware. For example, the acquisition module 501 can be a separate processing element, or it can be integrated into a chip in the above device. Alternatively, it can be stored as program code in the memory of the above device, and its functions can be called and executed by a processing element of the device. The implementation of other modules is similar. Moreover, these modules can be fully or partially integrated together, or they can be implemented independently. The processing element here can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each of the above modules can be completed through the integrated logic circuits in the hardware of the processor element or through software instructions.

[0112] Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 6 As shown, the electronic device may include: a transceiver 601, a processor 602, and a memory 603.

[0113] The processor 602 executes computer execution instructions stored in the memory, causing the processor 602 to perform the scheme in the above embodiments. The processor 602 can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0114] The memory 603 is connected to the processor 602 via the system bus and completes communication between them. The memory 603 is used to store computer program instructions.

[0115] Transceiver 601 can be used to obtain the task to be run and its configuration information.

[0116] The system bus can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The system bus can be divided into address bus, data bus, control bus, etc. For ease of representation, only one thick line is used in the diagram, but this does not indicate that there is only one bus or one type of bus. Transceivers are used to enable communication between database access devices and other computers (e.g., clients, read-write libraries, and read-only libraries). Memory may include random access memory (RAM) and may also include non-volatile memory.

[0117] The electronic device provided in this application embodiment can be the terminal device described in the above embodiments.

[0118] This application also provides a chip for executing instructions, which is used to execute the technical solution of the vehicle braking force distribution method in the above embodiments.

[0119] This invention also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the vehicle braking force distribution method described above.

[0120] This application also provides a computer program product, which includes a computer program stored in a computer-readable storage medium. At least one processor can read the computer program from the computer-readable storage medium. When the at least one processor executes the computer program, it can implement the technical solution of the vehicle braking force distribution method in the above embodiments.

[0121] In the several embodiments provided by this invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or modules, and may be electrical, mechanical, or other forms.

[0122] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to implement the solution of this embodiment according to actual needs.

[0123] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each module can exist physically separately, or two or more modules can be integrated into one unit. The unit composed of the above modules can be implemented in hardware or in the form of hardware plus software functional units.

[0124] The integrated modules implemented as software functional modules described above can be stored in a computer-readable storage medium. These software functional modules, stored in a storage medium, include several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute some steps of the methods described in the various embodiments of this application.

[0125] The aforementioned storage medium can be implemented from any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The storage medium can be any available medium accessible to general-purpose or special-purpose computers.

[0126] An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Alternatively, the storage medium can be an integral part of the processor. Both the processor and the storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and storage medium can exist as discrete components in an electronic device or host device.

[0127] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0128] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for distributing braking force to a vehicle, characterized in that, The method, applied to a vehicle controller for electric vehicles, includes: Obtain the braking signal from the vehicle's brake pedal, and calculate the vehicle's total braking force based on the braking signal; Determine the critical braking force required for front axle lock-up, the maximum permissible regenerative braking force for rear axle, and the critical braking force required for rear axle lock-up. If it is determined that the current driving speed of the vehicle is greater than the minimum speed at which regenerative braking is triggered, then the rear axle braking force of the vehicle is determined based on the total braking force and the I curve; wherein, the I curve is the relationship curve that the front axle braking force and the rear axle braking force should satisfy in order for the front and rear wheels of the vehicle to lock simultaneously when the vehicle is braking, and the I curve is obtained by force analysis calculation of the vehicle during braking. If a tendency for the front wheels of the vehicle to lock up is detected, the braking force of the front axle of the vehicle is set to the critical braking force required for front axle lockup. If it is determined that the rear axle braking force is greater than the maximum allowable regenerative braking force of the rear axle, then the mechanical braking force of the vehicle's rear axle is set to the difference between the rear axle braking force and the maximum allowable regenerative braking force of the rear axle, and the regenerative braking force of the vehicle's rear axle is set to the maximum allowable regenerative braking force of the rear axle. If a tendency for the rear wheels of the vehicle to lock up is detected, the braking force of the rear axle of the vehicle is set to the critical braking force required for rear axle lockup.

2. The method according to claim 1, characterized in that, The step of acquiring the braking signal from the vehicle's brake pedal and obtaining the vehicle's total braking force based on the braking signal includes: Obtain the vehicle's braking signal and calculate the braking deceleration based on the braking signal; Receive identification data sent by the vehicle's road surface recognition device, load recognition device, and slope recognition device; The total braking force of the vehicle is calculated based on the braking deceleration and the identification data.

3. The method according to claim 1, characterized in that, The calculation of the vehicle's rear axle braking force based on the total braking force and the I-curve includes: If the target deceleration of the vehicle is detected to be less than the first deceleration, then the rear axle braking force is determined to increase from zero to the maximum allowable regenerative braking force of the rear axle as the brake pedal opening increases; wherein, the first deceleration is the deceleration of the vehicle when the maximum regenerative braking force is fully utilized, and the maximum regenerative braking force is obtained through calibration; If the target deceleration of the vehicle is detected to be greater than the first deceleration and less than the second deceleration, then the rear axle braking force is determined to be the maximum regenerative braking force allowed by the rear axle; wherein, the second deceleration is the deceleration of the vehicle when the distribution of the front axle braking force and the rear axle braking force will reach the I curve; If the target deceleration is detected to be greater than the second deceleration, the total braking force is distributed based on the I curve to obtain the rear axle braking force.

4. The method according to claim 1, characterized in that, After obtaining the total braking force of the vehicle based on the braking signal, the method further includes: If the vehicle speed is determined to be less than or equal to the minimum speed at which regenerative braking is triggered, then the mechanical braking of the vehicle's electromechanical braking system is activated.

5. The method according to claim 1, characterized in that, Also includes: If it is determined that the rear axle braking force is less than or equal to the maximum allowable regenerative braking force of the rear axle, then regenerative braking of the vehicle's regenerative braking energy recovery system is executed. If a tendency for the rear wheels of the vehicle to lock up is detected, the braking force of the rear axle of the vehicle is set to the critical braking force required for rear axle lockup.

6. The method according to any one of claims 1 to 5, characterized in that, After setting the rear axle braking force of the vehicle to the critical braking force required for rear axle lockup, the method further includes: If it is determined that the critical braking force required for rear axle lock-up is greater than or equal to the maximum allowable regenerative braking force of the rear axle, then the regenerative braking force of the vehicle's rear axle is set to the maximum allowable regenerative braking force of the rear axle, and the mechanical braking force of the vehicle's rear axle is set to the difference between the critical braking force required for rear axle lock-up and the maximum allowable regenerative braking force of the rear axle. If it is determined that the critical braking force required for rear axle lock-up is less than the maximum allowable regenerative braking force of the rear axle, then the regenerative braking force used when the rear wheels of the vehicle are critically locked-up is determined, and the regenerative braking force of the rear axle of the vehicle is set as the regenerative braking force used when the rear wheels are critically locked-up.

7. A vehicle brake force distribution device, characterized in that, include: The acquisition module is used to acquire the braking signal from the vehicle's brake pedal and obtain the total braking force of the vehicle based on the braking signal. The first determining module is used to determine the critical lock-up braking force of the front axle, the maximum allowable regenerative braking force of the rear axle, and the critical lock-up braking force of the rear axle. The second determining module is used to determine the rear axle braking force of the vehicle based on the total braking force and the I curve if it is determined that the current driving speed of the vehicle is greater than the minimum vehicle speed for triggering regenerative braking. The I curve is a relationship curve that the front axle braking force and the rear axle braking force should satisfy in order for the front and rear wheels of the vehicle to lock up simultaneously when the vehicle is braking. The I curve is obtained by force analysis calculation of the vehicle during braking. The first setting module is used to set the front axle braking force of the vehicle to the critical front axle lock-up braking force if a tendency to lock up the front wheels of the vehicle is detected. The second setting module is used to set the mechanical braking force of the rear axle of the vehicle to the difference between the rear axle braking force and the maximum allowable regenerative braking force of the rear axle if it is determined that the rear axle braking force is greater than the maximum allowable regenerative braking force of the rear axle, and to set the regenerative braking force of the rear axle of the vehicle to the maximum allowable regenerative braking force of the rear axle. The third setting module is used to set the rear axle braking force of the vehicle to the critical rear axle lock-up braking force if a tendency to lock up the rear wheels of the vehicle is detected.

8. A vehicle controller, characterized in that, include: At least one processor and memory; The memory stores computer-executed instructions; The at least one processor executes computer execution instructions stored in the memory, causing the at least one processor to perform the method as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1 to 6.

10. A computer program product, characterized in that, Includes a computer program that, when executed by a processor, implements the method of any one of claims 1 to 6.

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