Braking torque control method, device, electronic device and storage medium

Abstract

The present invention discloses a braking torque control method, device, electronic device, and storage medium. The method comprises the following steps: determining the actual slip rate of each wheel based on the theoretical vehicle speed, the actual rotational speed of each wheel, and the radius correction rate; determining the locking braking torque and brake loss torque of each wheel based on the actual slip rate of each wheel; and determining the difference between the locking braking torque and the brake loss torque of each wheel as the first target braking torque for each wheel. This method solves the problem of vehicle instability, improves vehicle safety during braking, increases the slip rate calculation accuracy, and prevents the vehicle's anti-lock braking function from being erroneously triggered.

Description

Technical Field

[0001] The present invention relates to the field of vehicle braking technology, and in particular to a braking torque control method, device, electronic equipment and storage medium. Background Art

[0002] Anti-lock braking (ABS) is a vehicle braking function and a crucial element in ensuring driving safety. Current ABS issues include: ① Low slip calculation accuracy leads to misjudgment of wheel status, triggering the ABS algorithm and causing system malfunction; ② During braking, if the driver is unaware that a wheel is locked, continuously applying the brake pedal causes each wheel to continuously perform ABS control based on the braking torque obtained by the pedal in real time. This results in dynamic modulation of wheel braking torque, poor algorithm control stability, and compromised driving safety; ③ Due to differences in wheel load and tire surface properties, the maximum braking torque available to each wheel varies. While some wheels are locked, others remain operational and braking torque continues to increase. However, the normal wheels are not used to compensate for the lost braking torque, resulting in inadequate vehicle braking performance and increased braking distance, reducing vehicle safety. ④ Failure to consider the mechanical and hydraulic capabilities of each wheel during ABS control can lead to system overload and damage. Summary of the Invention

[0003] In view of the above defects or improvement needs of the prior art, an object of the present invention is to provide a method, device, electronic device and storage medium for controlling braking torque.

[0004] To achieve this object, the present invention adopts the following technical solutions:

[0005] In a first aspect, a method for controlling braking torque comprises the following steps:

[0006] determining an actual slip rate of each wheel based on the theoretical vehicle speed, the actual rotation speed of each wheel, and the radius correction rate;

[0007] The locking braking torque and the braking loss torque of each wheel are determined according to the actual slip rate of each wheel, and the difference between the locking braking torque and the braking loss torque of each wheel is determined as the first target braking torque of each wheel.

[0008] In one embodiment, the step of determining the actual slip rate of each wheel based on the theoretical vehicle speed, the actual rotation speed of each wheel, and the radius correction rate includes:

[0009] Determine the original vehicle speed through positioning equipment;

[0010] determining a turning radius of each wheel according to a steering wheel angle and a navigation angle of each wheel;

[0011] The original vehicle speed and the turning radius of each wheel are determined, and the theoretical vehicle speed of each wheel is determined.

[0012] In one embodiment, the step of determining the actual slip rate of each wheel based on the theoretical vehicle speed, the actual rotation speed of each wheel, and the radius correction rate further includes:

[0013] The radius correction rate under the current vehicle pressure is determined based on the current tire pressure of the wheel, the maximum tire pressure value, and the minimum correction coefficient calibrated at the minimum tire pressure.

[0014] In one embodiment, the step of determining the locking braking torque of each wheel comprises:

[0015] Determine the base braking torque of each wheel based on the brake pedal opening, wherein the sum of the base braking torques of the two left wheels is equal to the sum of the base braking torques of the two right wheels;

[0016] When the actual slip rate rises to a first slip rate threshold, the basic braking torque at that moment is determined as the locking braking torque and maintained until the actual slip rate drops to a set second slip rate threshold, at which time the basic braking torque is determined in real time as the locking braking torque, wherein the first slip rate threshold is greater than the second slip rate threshold.

[0017] In one embodiment, the step of determining the braking loss torque of each wheel includes:

[0018] When the actual slip rate is greater than the set lock-up slip rate threshold, the lock-up braking torque is equal to the base braking torque at the first moment when the slip rate is greater than the set lock-up slip rate threshold; and remains unchanged until the actual slip rate is less than the set lock-up slip rate threshold.

[0019] In one embodiment, after determining the first target braking torque for each wheel, the method further includes:

[0020] determining a compensation value of a lost braking torque of any one of the two wheels on the same side to the other wheel according to a wheel locking slip ratio threshold and a wheel normal selection slip ratio threshold;

[0021] determining a second target braking torque for each wheel according to the first target braking torque, the basic braking torque, and the compensation value of the loss braking torque;

[0022] A third target braking torque is determined based on the second target braking torque of each wheel and the maximum allowable braking torque of each wheel.

[0023] In one embodiment, the fourth target braking torque is determined according to the minimum value of the sum of the left and right braking torques and the third target braking torque.

[0024] In a second aspect, a braking torque control device includes:

[0025] The first module is used to determine the actual slip rate of each wheel according to the theoretical vehicle speed, the actual rotation speed of each wheel and the radius correction rate;

[0026] The second module is used to determine the locking braking torque and the braking loss torque of each wheel according to the actual slip rate of each wheel, and determine the difference between the locking braking torque and the braking loss torque of each wheel as the first target braking torque of each wheel.

[0027] According to a third aspect, an electronic device includes:

[0028] At least one processor, at least one memory and a communication interface; wherein,

[0029] The processor, memory and communication interface communicate with each other;

[0030] The memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the above-mentioned braking torque control method.

[0031] In a fourth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, wherein the computer instructions enable the computer to execute the above-mentioned braking torque control method.

[0032] Beneficial effects of the present invention:

[0033] For the control method, device, electronic device and storage medium of braking torque, the actual slip rate of each wheel is determined according to the theoretical vehicle speed, the actual rotation speed of each wheel and the radius correction rate; the locking braking torque and braking loss torque of each wheel are determined according to the actual slip rate of each wheel, and the difference between the locking braking torque and the braking loss torque of each wheel is determined as the first target braking torque of each wheel, which solves the problem of vehicle instability, improves the safety of the vehicle during braking, improves the calculation accuracy of the slip rate, and prevents the vehicle's anti-lock braking function from being triggered incorrectly.

[0034] Additional aspects and advantages of the present application will be given in part in the following description, which will become apparent from the following description, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0036] Figure 1 1 is a flow chart of a method for controlling braking torque according to an embodiment of the present application;

[0037] Figure 2 is a structural schematic diagram of a braking torque control device according to an embodiment of the present application;

[0038] Figure 3 It is a schematic structural diagram of an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0039] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0040] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0041] Those skilled in the art will understand that, unless otherwise stated, the singular forms "a," "an," "said," and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of this application refers to the presence of the stated features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.

[0042] Those skilled in the art will understand that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as those generally understood by those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with those in the context of the prior art, and will not be interpreted in an idealized or overly formal sense unless specifically defined as in the examples of this application.

[0043] This embodiment provides a method for controlling braking torque, such as Figure 1 As shown, the method includes steps S10-S20.

[0044] Specifically, S10, determining the actual slip rate of each wheel according to the theoretical vehicle speed, the actual rotation speed of each wheel, and the radius correction rate:

[0045]

[0046] Where: S lf Indicates the actual slip rate of the left front wheel, S lr Indicates the actual slip rate of the left rear wheel, S rf Indicates the actual slip rate of the right front wheel, S rr Indicates the actual wheel slip rate of the right rear vehicle, w lf Indicates the actual speed of the left front wheel, w lr Indicates the actual speed of the left rear wheel, w rf Indicates the actual speed of the right front wheel, w rr Indicates the actual speed of the right rear wheel, r max Indicates that the wheel is at the maximum tire pressure P max The maximum radius under lf Indicates the half-jin correction coefficient of the left front wheel, β lr Indicates the half-jin correction coefficient of the left front wheel, β rf Indicates the half-jin correction coefficient of the left front wheel, β rr Indicates the half-jin correction coefficient of the left front wheel.

[0047] Where: β lf , β lr , β rf , β rr These four correction coefficients are affected by the tire pressure. The higher the tire pressure, the larger the tire radius. Its value range is (β min ,1],β min is the minimum value of the correction coefficient, which is obtained when the tire pressure is equal to 0. The fitting principle of the relationship between these four correction coefficients and tire pressure is to take the maximum value P max When the actual tire pressure is equal to 0, the correction coefficient is β min The fitting formula between the four correction coefficients and tire pressure is:

[0048]

[0049] Step S10 also includes: obtaining the vehicle speed v at the center of the vehicle in real time through GPS or Beidou signal o .

[0050] Step S10 also includes calculating the basic braking torque of each wheel:

[0051]

[0052] Where: T lfrepresents the basic braking torque of the left front wheel calculated based on the brake pedal opening; T lr represents the basic braking torque of the left rear wheel calculated based on the brake pedal opening; T rf represents the basic braking torque of the right front wheel calculated based on the brake pedal opening; T rr represents the basic braking torque of the right rear wheel calculated based on the brake pedal opening; α represents the brake pedal opening obtained by the basic brake pedal sensor; l lf 、l lr 、l rf 、l rr It represents the basic braking torque function relationship calculated based on the brake pedal opening for the left front, left and right, right front, and right rear respectively, and can be set as a linear relationship according to needs.

[0053] Furthermore, in order to make the vehicle's additional yaw torque equal to 0, the left basic braking torque needs to be equal to the right basic braking torque, that is, it must satisfy: T lf +T lr =T rf +T rr .

[0054] Step S10 also includes: obtaining the theoretical speed of each wheel according to the vehicle steering wheel angle and using the Ackerman steering model: when the vehicle is traveling in a straight line, the theoretical speed of each wheel is equal to the speed v at the center of the vehicle o When the vehicle is in a turning state, the speed of each wheel is equal to the speed v at the center of the vehicle according to the Ackerman steering model. o Multiply by the ratio of each wheel's turning radius to the turning radius at the center of the vehicle.

[0055] Furthermore, when the vehicle is traveling in a straight line, that is, the absolute value of the vehicle's steering wheel angle θ is less than or equal to the threshold value θ1 of the steering wheel when traveling in a straight line, the calculation formula for the theoretical speed of each wheel is:

[0056]

[0057] Among them, v lf Indicates the theoretical speed of the left front wheel, v lr Indicates the theoretical speed of the right front wheel, v rf Indicates the theoretical speed of the left rear wheel, v rr Indicates the theoretical vehicle speed of the right rear wheel.

[0058] Furthermore, when the vehicle is traveling in a straight line, that is, the absolute value of the vehicle's steering wheel angle θ is greater than or equal to the steering wheel threshold θ2 when traveling in a straight line, the calculation formula for the theoretical speed of each wheel is:

[0059]

[0060] Where: R lf Indicates the turning radius of the left front wheel; R lr Indicates the turning radius of the left rear wheel; R rf Indicates the turning radius of the right front wheel; R rr Indicates the turning radius of the right rear wheel; R o Indicates the turning radius at the exact center of the vehicle.

[0061] Furthermore, the calculation method of the turning radius is:

[0062]

[0063] Where: θ lf represents the navigation angle of the left front wheel; θ rf θ represents the navigation angle of the right front wheel. lf ,θ rf Both represent high-order polynomials of the vehicle's steering wheel angle θ.

[0064] Furthermore, we can know that: θ2>θ1>0.

[0065] Step S20: Determine the locking braking torque and the braking loss torque of each wheel according to the actual slip rate of each wheel, and determine the difference between the locking braking torque and the braking loss torque of each wheel as the first target braking torque of each wheel.

[0066] Specifically, when the actual slip rate is greater than the set locking slip rate threshold, the locking braking torque is equal to the basic braking torque at the first moment when the slip rate is greater than the set locking slip rate threshold. In subsequent slip states, the locking braking torque is locked and remains unchanged until the slip rate is less than the set non-locking slip rate threshold. At this point, the locking braking torque is dynamically and in real time equal to the basic braking torque, calculated using the formula:

[0067]

[0068] Where: T lf1 Indicates the left front wheel locking braking torque, T lr1 Indicates the left rear wheel locking braking torque, T rf1 Indicates the right front wheel locking braking torque, T rr1 represents the locking braking torque of the right rear wheel, S_1 represents the locking slip rate threshold, and S2 represents the unlocking slip rate threshold.

[0069] Furthermore, once the wheels are locked, T lf1 、T lr1 、T rf1 、T rr1It is equal to the basic braking torque at the first moment of the locking state and will not change until the road adhesion coefficient becomes high enough to provide sufficient braking force for the wheels to work normally, and then it will be dynamically equal to the real-time basic braking torque again.

[0070] Step S20 also includes: using the four-wheel PI parameter method to calculate the braking loss torque of each wheel due to the slip rate.

[0071] It can be understood that the greater the slip rate, the greater the braking torque of the wheel. If the slip rate exceeds the upper limit of the slip rate, the braking torque should be reduced to prevent the wheel from locking and affecting driving safety.

[0072]

[0073] Where: ΔT lf1 Indicates the left front brake loss torque calculated based on the basic slip ratio; ΔT lr1 Indicates the left rear brake loss torque calculated based on the basic slip ratio; ΔT rf1 Indicates the right front brake loss torque calculated based on the basic slip ratio; ΔT rr1 It represents the right rear brake loss torque calculated based on the basic slip rate; k1 represents the brake torque proportional adjustment coefficient; k2 represents the brake torque integral adjustment coefficient; S3 represents the wheel locking slip rate threshold; S4 represents the wheel normal rotation slip rate threshold.

[0074] Furthermore, if each wheel is in a non-locking slip state, T lf1 , ΔT lr1 , ΔT rf1 , ΔT rr1 The value is equal to 0; if each wheel is in the locked slip state, T lf1 , ΔT lr1 , ΔT rf1 , ΔT rr1 The value is greater than 0, and the braking torque should be reduced.

[0075] The values ​​of k1 and k2 are both positive numbers.

[0076] Furthermore, S3>S1>S4>S2.

[0077] Furthermore, a first target braking torque is calculated according to the locking braking torque and the loss torque of each wheel.

[0078]

[0079] Where: T lf1 ' represents the first target braking torque of the left front wheel; T lr1 ' represents the first target braking torque of the left rear wheel; T rf1 ' represents the first target braking torque of the right front wheel; Trr1 ' represents the first target braking torque of the right rear wheel.

[0080] If the wheel is in normal rotation, its braking loss torque is equal to 0, and its first target braking torque is equal to the basic braking torque calculated based on the brake pedal opening.

[0081] If the wheel is in a locked state and its braking loss torque is greater than 0, its first target braking torque is less than the basic braking torque calculated based on the brake pedal opening.

[0082] At this time, the first target braking torque can be used as output.

[0083] Furthermore, the wheel braking loss torque causes the braking torque to decrease, which weakens the braking performance of the entire vehicle. In order to meet the braking requirements of the entire vehicle to the greatest extent, the braking torque compensation value of each wheel pair on the same side is calculated. The calculation method of the braking torque compensation value is as follows: among the two wheels on the same side, if one wheel is in a slipping state, that is, the slip rate of the wheel is greater than the normal rotation slip rate threshold S_4 of the wheel, it means that the wheel is unable to compensate for the braking loss torque of the other wheel on the same side; if the braking loss torque of one wheel is equal to 0, it means that the wheel does not need the braking torque compensation of the other wheel on the same side; if one wheel is in a non-slipping state and the braking loss torque of the other wheel is not equal to 0, it means that the wheel in the non-slipping state needs to compensate for the braking loss torque of the other wheel. Through this compensation value, the driver's demand for the braking force of the entire vehicle is met to the greatest extent. The compensation value must not only meet the requirements of not locking the wheel (the slip rate is too large) but also the compensation value cannot exceed the braking loss torque. That is, the calculation formula is:

[0084]

[0085] Where: ΔT lf2 Indicates the compensation value of the left front wheel's lost braking torque on the left rear wheel, ΔT lr2 Indicates the compensation value of the left rear wheel's lost braking torque on the left front wheel, ΔT rf2 Indicates the compensation value of the right front wheel's lost braking torque on the right rear wheel, ΔT rr2 represents the compensation value of the right front wheel for the lost braking torque of the right rear wheel, τ1 and τ2 represent the compensation value calculation coefficients, and Δs represents the slip rate misalignment interval value for torque compensation. It should be noted that Δs can be calibrated based on experience.

[0086] The second target braking torque for each wheel is calculated based on the first target braking torque, the base braking torque, and the compensation value for the lost braking torque. Due to the locked state, the first target braking torques T_lf1^', T_lr1^', T_rf1^', and T_rr1^' represent the road surface that can provide the maximum braking torque, whose value is determined by the road surface. The base braking torque represents the driver's intended torque. If the base braking torque of each wheel is greater than its first target braking torque, the road surface cannot provide it, so the second target braking torque is equal to the smaller of its base braking torque and its first target braking torque. If the base braking torque of each wheel is less than or equal to its first target braking torque, to meet the driver's braking requirements, the second target braking torque remains equal to the smaller of its base braking torque and its first target braking torque. Furthermore, the compensation value for the lost braking torque is added to the second target braking torque of each wheel, namely:

[0087]

[0088] Where: T lf2 The second theoretical braking torque target braking torque of the left front wheel is T lr2 The second theoretical braking torque target braking torque of the left rear wheel is T rf2 represents the second theoretical braking torque target braking torque of the right front wheel; T rr2 Indicates the second theoretical braking torque target braking torque of the right rear wheel.

[0089] The third target braking torque is calculated based on the maximum braking torque allowed for each wheel and its second target braking torque. The calculation formula is:

[0090]

[0091] Where: T lf3 represents the third theoretical braking torque target braking torque of the left front wheel, T lr3 The third theoretical braking torque target braking torque of the left rear wheel is T rf3 represents the third theoretical braking torque target braking torque of the right front wheel, T rr3 represents the third theoretical braking torque target braking torque of the right rear wheel, T lfmax Indicates the maximum braking torque allowed for the left front wheel, T lrmax Indicates the maximum braking torque allowed for the left rear wheel, T rfmax Indicates the maximum braking torque allowed for the right front wheel, T rrmax Indicates the maximum braking torque allowed for the right rear wheel.

[0092] It should be noted that T lfmax 、T lrmax 、T rfmax 、T rrmaxDetermined by the characteristics of the brake system's mechanical and hydraulic systems.

[0093] Furthermore, to prevent the vehicle from becoming unstable due to the additional yaw torque generated by the braking force on the center of the vehicle during braking, the sum of the braking torques on the left and right sides is the same. To meet this requirement, the minimum sum of the braking torques on the left and right sides is calculated, that is: T min =min(T lf3 +T lr3 ,T rf3 +T rr3 );

[0094] Among them, T min Indicates the minimum value of the sum of the braking torques on the left and right sides.

[0095] Furthermore, according to the minimum value T of the sum of the braking torques on the left and right sides min , the third target braking torque T of the left front wheel lf3 and the third target braking torque T for the right front wheel rf3 Calculate the fourth target braking torque executed by each wheel. The fourth target braking torque of the left front wheel is equal to the minimum value T of the sum of the braking torques on the left and right sides. min The third target braking torque T of the left front wheel lf3 The fourth target braking torque of the left rear wheel is equal to the minimum value T of the sum of the braking torques on both sides min Subtract the left front wheel target braking torque; the fourth target braking torque of the right front wheel is equal to the minimum value T of the sum of the braking torques on the left and right sides min The third target braking torque T of the right front wheel lf3 The fourth target braking torque of the right rear wheel is equal to the minimum value T of the sum of the braking torques on both sides min Subtract the target braking torque of the right front wheel, that is:

[0096]

[0097] Where: T lftarget represents the fourth target braking torque of the left front wheel; T lrtarget represents the fourth target braking torque of the left rear wheel; T rftarget represents the fourth target braking torque of the right front wheel; T rrtarget Indicates the fourth target braking torque of the right rear wheel.

[0098] Alternatively, the following calculation method can be used:

[0099]

[0100]

[0101]

[0102] The braking torque control method provided in this embodiment has the following technical effects:

[0103] The sum of the target braking torques on the left and right sides of the vehicle is equal, which avoids the problem of the braking force generating an additional yaw torque on the center of the vehicle during braking, thereby changing the vehicle's lateral motion state and causing vehicle instability, thereby improving vehicle safety during braking;

[0104] The target braking torque of each wheel always works within its allowable output capacity, avoiding the mechanical hydraulic system from over-capacity operation and improving the service life of the system;

[0105] Calculating the slip rate of each wheel using the Ackerman steering model combined with tire radius correction can accurately obtain the slip rate of each wheel, improve the calculation accuracy of the slip rate, and prevent the vehicle's anti-lock braking function from being triggered incorrectly. Due to the different wheel states and wheel loads of the vehicle, the maximum braking torque that the road surface can provide to each wheel is different, some of which are large and some are small. During the vehicle's emergency braking process, the lost torque is compensated through mutual compensation between the wheels on the same side. The maximum braking torque of each wheel and the road surface is utilized to the greatest extent to meet the basic braking torque requirements of the vehicle, which can shorten the braking distance and improve the braking performance and safety of the vehicle.

[0106] During the braking process, when the wheel is in a locked state, even if the driver is unaware of the wheel locking state, if he continues to press the brake pedal deeper to require a larger basic braking torque, but the road surface cannot provide it, the locking braking torque and the first target braking torque remain unchanged. Then, in step 8, the larger basic braking torque is compared with the unchanged first target braking torque to obtain the smaller value, and the output result is stabilized as the first target braking torque, preventing the wheel from entering dynamic adjustment again. This process makes the wheel anti-lock performance more stable and improves the safety of the vehicle.

[0107] This embodiment also provides a braking torque control device, Figure 2 It is a structural diagram of the braking torque control device, such as Figure 2 As shown, the braking torque control device includes a first module 21 and a second module 22 .

[0108] The first module 21 is used to determine the actual slip rate of each wheel according to the theoretical vehicle speed, the actual rotation speed of each wheel and the radius correction rate;

[0109] The second module 22 is used to determine the locking braking torque and the braking loss torque of each wheel according to the actual slip rate of each wheel, and determine the difference between the locking braking torque and the braking loss torque of each wheel as the first target braking torque of each wheel.

[0110] It should be noted that the braking torque control device provided in this embodiment can also be a computer program (including program code) running in a computer device. For example, the braking torque control device is an application program that can be used to execute the corresponding steps in the above method provided in the embodiment of this application.

[0111] In some feasible implementations, the braking torque control device provided in this embodiment can be implemented by a combination of software and hardware. As an example, the braking torque control device of the embodiment of the present application can be a processor in the form of a hardware decoding processor, which is programmed to execute the braking torque control method provided in the embodiment of the present application. For example, the processor in the form of a hardware decoding processor can adopt one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field programmable gate arrays (FPGAs) or other electronic components.

[0112] In some feasible implementations, the braking torque control device provided in this embodiment can be implemented in software, which can be software in the form of programs and plug-ins, and include a series of modules to implement the parking positioning control method provided in the embodiment of the present invention.

[0113] The braking torque control device provided in this embodiment has the following technical effects:

[0114] The sum of the target braking torques on the left and right sides of the vehicle is equal, which avoids the problem of the braking force generating an additional yaw torque on the center of the vehicle during braking, thereby changing the vehicle's lateral motion state and causing vehicle instability, thereby improving vehicle safety during braking;

[0115] The target braking torque of each wheel always works within its allowable output capacity, avoiding the mechanical hydraulic system from over-capacity operation and improving the service life of the system;

[0116] Calculating the slip rate of each wheel using the Ackerman steering model combined with tire radius correction can accurately obtain the slip rate of each wheel, improve the calculation accuracy of the slip rate, and prevent the vehicle's anti-lock braking function from being triggered incorrectly. Due to the different wheel states and wheel loads of the vehicle, the maximum braking torque that the road surface can provide to each wheel is different, some of which are large and some are small. During the vehicle's emergency braking process, the lost torque is compensated through mutual compensation between the wheels on the same side. The maximum braking torque of each wheel and the road surface is utilized to the greatest extent to meet the basic braking torque requirements of the vehicle, which can shorten the braking distance and improve the braking performance and safety of the vehicle.

[0117] During the braking process, when the wheel is in a locked state, even if the driver is unaware of the wheel locking state, if he continues to press the brake pedal deeper to require a larger basic braking torque, but the road surface cannot provide it, the locking braking torque and the first target braking torque remain unchanged. Then, in step 8, the larger basic braking torque is compared with the unchanged first target braking torque to obtain the smaller value, and the output result is stabilized as the first target braking torque, preventing the wheel from entering dynamic adjustment again. This process makes the wheel anti-lock performance more stable and improves the safety of the vehicle.

[0118] This embodiment also provides an electronic device, Figure 3 is a schematic diagram of the structure of an electronic device according to an embodiment of the present application. Figure 3 As shown, the electronic device 1000 in this embodiment may include: a processor 1001, a network interface 1004 and a memory 1005. In addition, the above-mentioned electronic device 1000 may also include: a user interface 1003, and at least one communication bus 1002. The communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a display screen (Display), a keyboard (Keyboard), and the user interface 1003 may optionally include a standard wired interface and a wireless interface. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a WI-FI interface). The memory 1004 may be a high-speed RAM memory, or a non-volatile memory (non-volatile memory), such as at least one disk memory. The memory 1005 may optionally be at least one storage device located away from the aforementioned processor 1001. As Figure 3 As shown, the memory 1005 as a computer-readable storage medium may include an operating system, a network communication module, a user interface module, and a device control application.

[0119] like Figure 3In the electronic device 1000 shown, the network interface 1004 can provide network communication functions; the user interface 1003 is mainly used to provide an interface for user input; and the processor 1001 can be used to call the device control application stored in the memory 1005 to achieve:

[0120] determining an actual slip rate of each wheel based on the theoretical vehicle speed, the actual rotation speed of each wheel, and the radius correction rate;

[0121] The locking braking torque and the braking loss torque of each wheel are determined according to the actual slip rate of each wheel, and the difference between the locking braking torque and the braking loss torque of each wheel is determined as the first target braking torque of each wheel.

[0122] It should be understood that in some feasible embodiments, the processor 1001 may be a central processing unit (CPU). The processor may also be another general-purpose processor, a DSP, an ASIC, an FPGA, or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, etc. The general-purpose processor may be a microprocessor or any conventional processor. The memory may include a read-only memory and a random access memory, and provides instructions and data to the processor. A portion of the memory may also include a non-volatile random access memory. For example, the memory may also store device type information.

[0123] In a specific implementation, the electronic device 1000 can execute the implementation methods provided by the various steps of the above control method through its built-in functional modules. For details, please refer to the implementation methods provided by the above steps, which will not be repeated here.

[0124] The electronic device provided in this embodiment has the following technical effects:

[0125] The sum of the target braking torques on the left and right sides of the vehicle is equal, which avoids the problem of the braking force generating an additional yaw torque on the center of the vehicle during braking, thereby changing the vehicle's lateral motion state and causing vehicle instability, thereby improving vehicle safety during braking;

[0126] The target braking torque of each wheel always works within its allowable output capacity, avoiding the mechanical hydraulic system from over-capacity operation and improving the service life of the system;

[0127] Calculating the slip rate of each wheel using the Ackerman steering model combined with tire radius correction can accurately obtain the slip rate of each wheel, improve the calculation accuracy of the slip rate, and prevent the vehicle's anti-lock braking function from being triggered incorrectly. Due to the different wheel states and wheel loads of the vehicle, the maximum braking torque that the road surface can provide to each wheel is different, some of which are large and some are small. During the vehicle's emergency braking process, the lost torque is compensated through mutual compensation between the wheels on the same side. The maximum braking torque of each wheel and the road surface is utilized to the greatest extent to meet the basic braking torque requirements of the vehicle, which can shorten the braking distance and improve the braking performance and safety of the vehicle.

[0128] During the braking process, when the wheel is in a locked state, even if the driver is unaware of the wheel locking state, if he continues to press the brake pedal deeper to require a larger basic braking torque, but the road surface cannot provide it, the locking braking torque and the first target braking torque remain unchanged. Then, in step 8, the larger basic braking torque is compared with the unchanged first target braking torque to obtain the smaller value, and the output result is stabilized as the first target braking torque, preventing the wheel from entering dynamic adjustment again. This process makes the wheel anti-lock performance more stable and improves the safety of the vehicle.

[0129] An embodiment of the present application also provides a computer-readable storage medium, which stores a computer program and is executed by a processor to implement the various steps in the braking torque control method in the above embodiment. For details, please refer to the implementation methods provided in the above steps, which will not be repeated here.

[0130] The computer-readable storage medium provided in this embodiment has the following technical effects:

[0131] The sum of the target braking torques on the left and right sides of the vehicle is equal, which avoids the problem of the braking force generating an additional yaw torque on the center of the vehicle during braking, thereby changing the vehicle's lateral motion state and causing vehicle instability, thereby improving vehicle safety during braking;

[0132] The target braking torque of each wheel always works within its allowable output capacity, avoiding the mechanical hydraulic system from over-capacity operation and improving the service life of the system;

[0133] Calculating the slip rate of each wheel using the Ackerman steering model combined with tire radius correction can accurately obtain the slip rate of each wheel, improve the calculation accuracy of the slip rate, and prevent the vehicle's anti-lock braking function from being triggered incorrectly. Due to the different wheel states and wheel loads of the vehicle, the maximum braking torque that the road surface can provide to each wheel is different, some of which are large and some are small. During the vehicle's emergency braking process, the lost torque is compensated through mutual compensation between the wheels on the same side. The maximum braking torque of each wheel and the road surface is utilized to the greatest extent to meet the basic braking torque requirements of the vehicle, which can shorten the braking distance and improve the braking performance and safety of the vehicle.

[0134] During the braking process, when the wheel is in a locked state, even if the driver is unaware of the wheel locking state, if he continues to press the brake pedal deeper to require a larger basic braking torque, but the road surface cannot provide it, the locking braking torque and the first target braking torque remain unchanged. Then, in step 8, the larger basic braking torque is compared with the unchanged first target braking torque to obtain the smaller value, and the output result is stabilized as the first target braking torque, preventing the wheel from entering dynamic adjustment again. This process makes the wheel anti-lock performance more stable and improves the safety of the vehicle.

[0135] It should be understood that although the steps in the flowcharts of the accompanying drawings are shown in sequence as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some of the steps in the flowcharts of the accompanying drawings may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0136] The above description is only part of the implementation methods of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for controlling braking torque, characterized in that: The following steps are involved: Determining the actual slip rate of each wheel based on the theoretical vehicle speed, the actual rotation speed of each wheel, and the radius correction rate; the step of determining the actual slip rate of each wheel based on the theoretical vehicle speed, the actual rotation speed of each wheel, and the radius correction rate comprises: determining the original vehicle speed using a positioning device; determining the turning radius of each wheel based on the steering wheel angle and the navigation angle of each wheel; and determining the theoretical vehicle speed of each wheel based on the original vehicle speed and the turning radius of each wheel; determining a locking braking torque and a braking loss torque of each wheel according to an actual slip rate of each wheel, and determining a difference between the locking braking torque and the braking loss torque of each wheel as a first target braking torque of each wheel; The step of determining the locking braking torque of each wheel includes: determining a base braking torque of each wheel based on a brake pedal opening, wherein the sum of the base braking torques of the two left wheels is equal to the sum of the base braking torques of the two right wheels; when the actual slip ratio rises to a first slip ratio threshold, determining the base braking torque at that moment as the locking braking torque and maintaining it until the actual slip ratio drops to a set second slip ratio threshold, then determining the base braking torque in real time as the locking braking torque, wherein the first slip ratio threshold is greater than the second slip ratio threshold; The step of determining the brake loss torque of each wheel includes: when the actual slip ratio is greater than a set locking slip ratio threshold, the locking braking torque is equal to the base braking torque at the first moment when the slip ratio is greater than the set locking slip ratio threshold; and remains unchanged until the actual slip ratio is less than the set locking slip ratio threshold; The step of determining the first target braking torque for each wheel also includes: determining the compensation value of the lost braking torque of any one of the two wheels on the same side to the other wheel based on the wheel locking slip rate threshold and the wheel normal selection slip rate threshold; determining the second target braking torque of each wheel based on the first target braking torque, the basic braking torque and the compensation value of the lost braking torque; and determining the third target braking torque based on the second target braking torque of each wheel and the maximum allowable braking torque of each wheel.

2. The method for controlling the braking torque according to claim 1, wherein: The step of determining the actual slip rate of each wheel according to the theoretical vehicle speed, the actual rotation speed of each wheel and the radius correction rate further includes: The radius correction rate under the current vehicle pressure is determined based on the current tire pressure of the wheel, the maximum tire pressure value, and the minimum correction coefficient calibrated at the minimum tire pressure.

3. The method for controlling the braking torque according to claim 1, wherein: The fourth target braking torque is determined according to the minimum value of the sum of the left and right braking torques and the third target braking torque.

4. A braking torque control device, using the braking torque control method according to any one of claims 1 to 3, characterized in that: include: The first module is used to determine the actual slip rate of each wheel according to the theoretical vehicle speed, the actual rotation speed of each wheel and the radius correction rate; The second module is used to determine the locking braking torque and the braking loss torque of each wheel according to the actual slip rate of each wheel, and determine the difference between the locking braking torque and the braking loss torque of each wheel as the first target braking torque of each wheel.

5. An electronic device, characterized in that: include: At least one processor, at least one memory and a communication interface; wherein, The processor, memory and communication interface communicate with each other; The memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the braking torque control method according to any one of claims 1 to 3.

6. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer instructions, and the computer instructions enable the computer to execute the braking torque control method according to any one of claims 1 to 3.

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