Vehicle control method, device and vehicle

Abstract

The application relates to a vehicle control method, device and vehicle. The method comprises the following steps: in the case that the wheel speed of a first wheel in the vehicle is detected to be lost, determining the current actual wheel speed of the first wheel according to the braking correlation parameter of the vehicle and the current actual wheel speed of each second wheel, determining the target adhesion coefficient of each wheel according to the braking correlation parameter and the current actual wheel speed and the historical adhesion coefficient of each wheel, determining the target motor torque of each wheel according to the braking correlation parameter and the target adhesion coefficient and the current actual wheel speed of each wheel, and controlling the operation of the corresponding wheel according to the target motor torque of each wheel, wherein the second wheel is a wheel in the vehicle except the first wheel. The method can improve the safety of the vehicle operation.

Description

Technical Field

[0001] This application relates to the field of vehicle driving technology, and in particular to a vehicle control method, device and vehicle. Background Technology

[0002] With the continuous development of the automotive industry, anti-lock braking systems (ABS) have emerged to ensure vehicle safety, preventing wheel lock-up during braking. Existing ABS typically rely on four wheel speed sensors to acquire real-time wheel speed information and calculate parameters such as wheel slip ratio based on this information, thereby adjusting braking pressure to achieve anti-lock control.

[0003] However, in actual vehicle operation, there may be situations where wheel speed information for any wheel is missing. In such cases, the above method cannot accurately obtain the motion state of each wheel, which reduces the reliability of vehicle control and thus reduces the safety of vehicle operation. Summary of the Invention

[0004] Therefore, it is necessary to provide a vehicle control method, device, and vehicle that can improve vehicle operation safety in response to the above-mentioned technical problems.

[0005] In a first aspect, this application provides a vehicle control method, including:

[0006] If the wheel speed of the first wheel in the vehicle is missing, the current actual wheel speed of the first wheel is determined based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel; wherein, each second wheel is the wheel of the vehicle other than the first wheel.

[0007] Based on the braking correlation parameters, as well as the current actual wheel speed and historical adhesion coefficient of each wheel, the target adhesion coefficient of each wheel is determined.

[0008] Based on the braking correlation parameters, the target adhesion coefficient of each wheel and the current actual wheel speed, the target motor torque of each wheel is determined, and the operation of the corresponding wheel is controlled according to the target motor torque of each wheel.

[0009] In one embodiment, the target adhesion coefficient for each wheel is determined based on braking correlation parameters, the current actual wheel speed, and the historical adhesion coefficient of each wheel, including:

[0010] For each wheel, the current slip ratio is determined based on the wheel's current actual wheel speed and the current vehicle speed in the braking-related parameters; the current adhesion coefficient is determined based on the braking-related parameters and the wheel's vertical load; and the target adhesion coefficient is determined based on the wheel's current slip ratio, current adhesion coefficient, and historical adhesion coefficient.

[0011] In one embodiment, the current coefficient of adhesion of the wheel is determined based on braking correlation parameters and the vertical load on the wheel, including:

[0012] Based on the current motor torque, wheel rolling radius, and transmission ratio of the wheel in the braking-related parameters, determine the ground adhesion driving force of the wheel; based on the ground adhesion driving force, as well as the wheel angular acceleration, wheel rolling radius, and wheel moment of inertia in the braking-related parameters, determine the actual ground adhesion force of the wheel; based on the actual ground adhesion force of the wheel and the vertical load, determine the current adhesion coefficient of the wheel.

[0013] In one embodiment, the target adhesion coefficient of the wheel is determined based on the wheel's current slip ratio, current adhesion coefficient, and historical adhesion coefficient, including:

[0014] The process involves: determining the target adhesion coefficient difference between the current and historical adhesion coefficients of the wheel; determining a first correction parameter based on the target adhesion coefficient difference and a first correspondence, wherein the first correspondence includes the correspondence between candidate adhesion coefficient differences and candidate correction parameters; determining a second correction parameter based on the current slip ratio of the wheel and a second correspondence, wherein the second correspondence includes the correspondence between candidate slip ratios and candidate correction parameters; correcting the target adhesion coefficient difference using the first and second correction parameters; and adjusting the historical adhesion coefficient using the corrected target adhesion coefficient difference to obtain the target adhesion coefficient of the wheel.

[0015] In one embodiment, the target motor torque for each wheel is determined based on braking correlation parameters, the target adhesion coefficient for each wheel, and the current actual wheel speed, including:

[0016] For each wheel, the corrected slip ratio is determined based on the wheel's target adhesion coefficient and the current vehicle speed in the braking-related parameters; the feedforward control torque of the wheel is determined based on the wheel's target adhesion coefficient and vertical load, as well as the target lateral acceleration and wheel rolling radius in the braking-related parameters; the wheel speed deviation value is determined based on the corrected slip ratio, the current vehicle speed, and the current actual wheel speed; and the target motor torque of the wheel is determined based on the feedforward control torque, the wheel speed deviation value, and the actual control torque of the wheel in the braking-related parameters.

[0017] In one embodiment, the corrected slip ratio is determined based on the target adhesion coefficient of the wheel and the current vehicle speed in the braking-related parameters, including:

[0018] The target slip ratio is determined based on the target adhesion coefficient of the wheel and the third correspondence; wherein the third correspondence includes the correspondence between candidate adhesion coefficients and candidate slip ratios; the target offset is determined based on the fourth correspondence and the current vehicle speed in the braking correlation parameters; wherein the fourth correspondence includes the correspondence between candidate vehicle speeds and candidate offsets; and the corrected slip ratio is determined based on the target slip ratio and the target offset.

[0019] In one embodiment, the feedforward control torque of the wheel is determined based on the target adhesion coefficient and vertical load of the wheel, as well as the target lateral acceleration in the braking correlation parameters, including:

[0020] The target longitudinal force factor is determined based on the longitudinal force factor correspondence and the target lateral acceleration in the braking correlation parameters; wherein, the longitudinal force factor correspondence includes the correspondence between candidate lateral acceleration and candidate longitudinal force factor; the wheel feedforward control torque is determined based on the target longitudinal force factor, vertical load, target adhesion coefficient and wheel rolling radius in the braking correlation parameters.

[0021] In one embodiment, the target motor torque of the wheel is determined based on the feedforward control torque, wheel speed deviation value, and the actual control torque of the wheel in the braking correlation parameters, including:

[0022] Based on the difference between the actual control torque of the wheel and the feedforward control torque in the braking correlation parameters, the basic correction torque of the wheel is determined; the wheel speed deviation value and the basic correction torque are fused using the controller adjustment coefficient to obtain the feedforward correction torque of the wheel; the target motor torque of the wheel is determined based on the feedforward control torque, the feedforward correction torque, the wheel rolling radius and the wheel transmission ratio.

[0023] In one embodiment, determining the current actual wheel speed of the first wheel based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel includes:

[0024] Based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel, determine the current reference wheel speed of the first wheel based on the prediction of each second wheel; based on the braking correlation parameters and each current reference wheel speed, determine the current actual wheel speed of the first wheel.

[0025] Secondly, this application also provides a vehicle control device, comprising:

[0026] The wheel speed determination module is used to determine the current actual wheel speed of the first wheel based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel when the wheel speed of the first wheel in the vehicle is detected to be missing; wherein, each second wheel is the wheel of the vehicle other than the first wheel.

[0027] The coefficient determination module is used to determine the target adhesion coefficient of each wheel based on the braking correlation parameters, the current actual wheel speed and historical adhesion coefficient of each wheel.

[0028] The vehicle control module is used to determine the target motor torque of each wheel based on braking correlation parameters, the target adhesion coefficient of each wheel and the current actual wheel speed, and control the operation of the corresponding wheel based on the target motor torque of each wheel.

[0029] Thirdly, this application also provides a vehicle, including a vehicle controller, and braking systems and sensors corresponding to each wheel; wherein the vehicle controller is connected to the braking system and the sensors;

[0030] When the vehicle controller detects a lack of wheel speed in the first wheel of the vehicle, it obtains the current actual wheel speed of each second wheel at the current moment through the sensors corresponding to the second wheels. Each second wheel is one of the vehicle's wheels excluding the first wheel. The vehicle controller determines the current actual wheel speed of the first wheel based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel. The vehicle controller determines the target adhesion coefficient of each wheel based on the braking correlation parameters, the current actual wheel speed, and the historical adhesion coefficient. The vehicle controller determines the target motor torque of each wheel based on the braking correlation parameters, the target adhesion coefficient, and the current actual wheel speed, and sends the target motor torque of each wheel to the corresponding wheel's braking system. The braking system corresponding to each wheel controls the operation of the corresponding wheel based on the target motor torque.

[0031] Fourthly, this application also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0032] If the wheel speed of the first wheel in the vehicle is missing, the current actual wheel speed of the first wheel is determined based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel; wherein, each second wheel is the wheel of the vehicle other than the first wheel.

[0033] Based on the braking correlation parameters, as well as the current actual wheel speed and historical adhesion coefficient of each wheel, the target adhesion coefficient of each wheel is determined.

[0034] Based on the braking correlation parameters, the target adhesion coefficient of each wheel and the current actual wheel speed, the target motor torque of each wheel is determined, and the operation of the corresponding wheel is controlled according to the target motor torque of each wheel.

[0035] Fifthly, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, performs the following steps:

[0036] If the wheel speed of the first wheel in the vehicle is missing, the current actual wheel speed of the first wheel is determined based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel; wherein, each second wheel is the wheel of the vehicle other than the first wheel.

[0037] Based on the braking correlation parameters, as well as the current actual wheel speed and historical adhesion coefficient of each wheel, the target adhesion coefficient of each wheel is determined.

[0038] Based on the braking correlation parameters, the target adhesion coefficient of each wheel and the current actual wheel speed, the target motor torque of each wheel is determined, and the operation of the corresponding wheel is controlled according to the target motor torque of each wheel.

[0039] Sixthly, this application also provides a computer program product, including a computer program that, when executed by a processor, performs the following steps:

[0040] If the wheel speed of the first wheel in the vehicle is missing, the current actual wheel speed of the first wheel is determined based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel; wherein, each second wheel is the wheel of the vehicle other than the first wheel.

[0041] Based on the braking correlation parameters, as well as the current actual wheel speed and historical adhesion coefficient of each wheel, the target adhesion coefficient of each wheel is determined.

[0042] Based on the braking correlation parameters, the target adhesion coefficient of each wheel and the current actual wheel speed, the target motor torque of each wheel is determined, and the operation of the corresponding wheel is controlled according to the target motor torque of each wheel.

[0043] The aforementioned vehicle control method, device, and vehicle, when detecting a lack of wheel speed in the first wheel, determine the current actual wheel speed of the first wheel based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel. Then, based on the braking correlation parameters, the current actual wheel speed of each wheel, and the historical adhesion coefficient, determine the target adhesion coefficient of each wheel. Finally, based on the braking correlation parameters, the target adhesion coefficient of each wheel, and the current actual wheel speed, determine the target motor torque of each wheel. The corresponding wheel's operation is then controlled based on the target motor torque. This method ensures, on the one hand, the accuracy of the determined current actual wheel speed is guaranteed by obtaining the current actual wheel speed of the first wheel based on the current actual wheel speed of each second wheel and the braking correlation parameters; on the other hand, by introducing the historical adhesion coefficient in the calculation of the target motor torque, frequent fluctuations in the adhesion coefficient can be avoided from affecting anti-skid control, thus ensuring the rationality of the subsequently calculated target motor torque and improving the safety of vehicle control. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is a flowchart illustrating a vehicle control method in one embodiment;

[0046] Figure 2 This is a flowchart illustrating the process of determining the target adhesion coefficient in one embodiment;

[0047] Figure 3 This is a schematic diagram of the process for determining the current adhesion coefficient in one embodiment;

[0048] Figure 4 This is a flowchart illustrating the process of determining the target adhesion coefficient in another embodiment;

[0049] Figure 5 This is a flowchart illustrating the process of determining the target motor torque in one embodiment;

[0050] Figure 6 This is a flowchart illustrating the process of determining the corrected slip ratio in one embodiment;

[0051] Figure 7 This is a flowchart illustrating the process of determining the target motor torque in another embodiment;

[0052] Figure 8 This is a flowchart illustrating the process of determining the current actual wheel speed in one embodiment;

[0053] Figure 9 This is a schematic diagram of the vehicle structure in one embodiment;

[0054] Figure 10 This is a flowchart illustrating the vehicle control method in another embodiment;

[0055] Figure 11 This is a structural block diagram of a vehicle control device in one embodiment;

[0056] Figure 12 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0058] With the continuous development of the automotive industry, anti-lock braking systems (ABS) have emerged to ensure vehicle safety, preventing wheel lock-up during braking. Existing ABS typically rely on four wheel speed sensors to acquire real-time wheel speed information and calculate parameters such as wheel slip ratio based on this information, thereby adjusting braking pressure to achieve anti-lock control.

[0059] However, in actual vehicle operation, there may be situations where wheel speed information for any wheel is missing. In such cases, the above method cannot accurately obtain the motion state of each wheel, which reduces the reliability of vehicle control and thus reduces the safety of vehicle operation.

[0060] Based on this, in an exemplary embodiment, a vehicle control method is provided, which is illustrated by taking the application of this method to a vehicle controller as an example. Figure 1 As shown, the specific steps include:

[0061] S101, when the wheel speed of the first wheel in the vehicle is detected to be missing, the current actual wheel speed of the first wheel is determined based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel.

[0062] The term "first wheel" refers to the wheel in the vehicle whose wheel speed is missing. Each "second wheel" refers to the wheel other than the first wheel. The "current actual wheel speed" is the rotational speed of the wheel at the current moment, as collected by the corresponding sensor on each wheel.

[0063] Braking-related parameters refer to parameters related to vehicle braking, which may include, but are not limited to, vehicle driving parameters, vehicle attribute parameters (such as vehicle size and weight parameters), brake parameters, and caliper braking parameters. Furthermore, vehicle attribute parameters are parameters inherent to the vehicle, which may include, but are not limited to, vehicle mass, vehicle size parameters, wheel size parameters, and wheel attribute parameters. Brake parameters are parameters related to the brakes in the wheel braking system, which may include, but are not limited to, caliper braking radius, brake disc friction coefficient, and transmission efficiency. Vehicle driving parameters are parameters related to vehicle speed during driving, which may include, but are not limited to, current vehicle speed, front wheel steering angle, and yaw rate. Motor braking parameters are parameters related to motor operation, which may include, but are not limited to, current motor torque and gear ratio.

[0064] The current actual wheel speed of each wheel can be obtained in real time by sensors deployed on each wheel. If the current actual wheel speed of any wheel is missing, the wheel with the missing wheel speed can be designated as the first wheel, and the other wheels can be designated as the second wheel.

[0065] In one alternative implementation, the wheel speed adjustment parameters corresponding to each of the second wheels can be determined based on the position of the first wheel. Then, the current actual wheel speed is weighted using the wheel speed adjustment parameters corresponding to each of the second wheels to obtain the current actual wheel speed of the first wheel.

[0066] In another alternative implementation, the current actual wheel speed of each second wheel can be directly input into a trained wheel speed determination model. The wheel speed determination model then outputs the current actual wheel speed of the first wheel based on the current actual wheel speed of each second wheel. The wheel speed determination model can be obtained by training a neural network model based on the sample actual wheel speeds of each wheel in the sample vehicle.

[0067] S102, based on the braking correlation parameters, as well as the current actual wheel speed and historical adhesion coefficient of each wheel, determine the target adhesion coefficient of each wheel.

[0068] The ground adhesion coefficient measures the degree to which the vehicle's actual road surface adhesion utilizes the road surface's maximum adhesion potential. The historical adhesion coefficient is the vehicle's ground adhesion coefficient over a historical period, which can be the vehicle's adhesion coefficient at the previous moment. The target adhesion coefficient is the optimal ground adhesion coefficient for the vehicle at the current moment.

[0069] Understandably, in order to avoid frequent fluctuations in the adhesion coefficient affecting anti-slip control, it is necessary to introduce historical adhesion coefficients to limit the determined target adhesion coefficient.

[0070] In one alternative implementation, for each wheel, the current adhesion coefficient at the current moment can be determined based on the vehicle driving parameters (such as current vehicle speed and vehicle acceleration parameters), vehicle attribute parameters (such as vehicle mass and vehicle size parameters) in the braking associated parameters, and the current actual wheel speed of the wheel; then, the current adhesion coefficient and the historical adhesion coefficient are fused to obtain the target adhesion coefficient of the wheel.

[0071] In another optional implementation, the vehicle driving parameters and vehicle attribute parameters from the braking correlation parameters, along with the current actual wheel speed and historical adhesion coefficient of the wheel, can be directly input into a trained first coefficient determination model. The first coefficient determination model then outputs the target adhesion coefficient of the wheel based on the vehicle driving parameters and vehicle attribute parameters from the braking correlation parameters, as well as the current actual wheel speed and historical adhesion coefficient of the wheel. The first coefficient determination model can be obtained by training a neural network model based on sample vehicle driving parameters, sample vehicle attribute parameters, sample current actual wheel speeds of each wheel, sample historical adhesion coefficients, and the corresponding sample target adhesion coefficients.

[0072] S103 determines the target motor torque for each wheel based on the braking correlation parameters, the target adhesion coefficient of each wheel, and the current actual wheel speed, and controls the operation of the corresponding wheel based on the target motor torque of each wheel.

[0073] The so-called target motor torque is the torque that each wheel-related motor is required to achieve.

[0074] In one alternative implementation, for each wheel, the wheel speed deviation value can be determined based on the vehicle driving parameters (such as current vehicle speed and target lateral acceleration) and wheel size parameters (such as wheel rolling radius) in the braking associated parameters, as well as the target adhesion coefficient and the current actual wheel speed of the wheel; then, the target motor torque of the wheel can be determined by combining the wheel speed deviation value of the wheel and the actual control torque of the wheel in the braking associated parameters.

[0075] In one optional implementation, the vehicle driving parameters and wheel size parameters from the braking correlation parameters, along with the target adhesion coefficient and current actual wheel speed of the wheel, can be directly input into a trained first torque determination model. The first torque determination model then outputs the target motor torque of the wheel based on the vehicle driving parameters, wheel size parameters, target adhesion coefficient, and current actual wheel speed. The first torque determination model can be obtained by training a neural network model based on sample vehicle driving parameters, sample wheel size parameters, sample target adhesion coefficient, sample current actual wheel speed, and the corresponding sample target motor torque of a sample vehicle.

[0076] Furthermore, after determining the target motor torque for the wheel, the target motor torque can be sent to the braking system corresponding to the wheel. The braking system then controls the motor associated with the wheel to operate based on the target motor torque, thereby achieving vehicle operation control.

[0077] In the aforementioned vehicle control method, when a lack of wheel speed in the first wheel is detected, the current actual wheel speed of the first wheel is determined based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel. Then, based on the braking correlation parameters, the current actual wheel speed of each wheel, and the historical adhesion coefficient, the target adhesion coefficient of each wheel is determined. Finally, based on the braking correlation parameters, the target adhesion coefficient of each wheel, and the current actual wheel speed, the target motor torque of each wheel is determined. The operation of the corresponding wheel is then controlled according to the target motor torque of each wheel. This method ensures the accuracy of the determined current actual wheel speed by obtaining the current actual wheel speed of the first wheel based on the current actual wheel speed of each second wheel and the braking correlation parameters. Furthermore, by introducing the historical adhesion coefficient into the calculation of the target motor torque, frequent fluctuations in the adhesion coefficient can be avoided from affecting anti-slip control, thus ensuring the rationality of the subsequently calculated target motor torque and improving the safety of vehicle control.

[0078] Based on the above embodiments, this application provides an optional method for determining the target adhesion coefficient, such as... Figure 2 As shown, the specific steps include:

[0079] S201, for each wheel, determine the current slip ratio of the wheel based on the wheel's current actual wheel speed and the current vehicle speed in the braking-related parameters.

[0080] The current slip ratio is used to characterize the degree of slippage at the wheel contact point at the current moment.

[0081] In one alternative implementation, for each wheel, the current slip ratio can be calculated based on the difference between the wheel's current actual wheel speed and the current vehicle speed. For example, the current slip ratio can be determined by referring to the following formula (1), based on the ratio between the difference between the current vehicle speed and the current actual wheel speed and the current vehicle speed. Where s is the current slip ratio; v veh v represents the current vehicle speed; v represents the current actual wheel speed.

[0082] (1)

[0083] S202, determine the current coefficient of adhesion of the wheel based on the braking correlation parameters and the vertical load of the wheel.

[0084] The vertical load refers to the total vehicle weight actually borne by a single wheel (including its own curb weight, load weight, and dynamic load), also known as the wheel-end axle load. The current coefficient of adhesion refers to the actual ground adhesion coefficient of the wheel at the current moment.

[0085] In one alternative implementation, for each wheel, the vertical load of the wheel can be calculated by taking into account the dynamic changes in the vehicle weight borne by the wheel at its location, the road gradient of the road where the vehicle is currently located, and information such as vehicle mass, vehicle size parameters, and vehicle acceleration parameters in the braking-related parameters.

[0086] For example, one can refer to the following formulas (2)-(5), based on the vehicle's longitudinal acceleration a x lateral acceleration a y The road gradient of the road in question Given the vehicle's mass m, gravitational acceleration g, wheelbase b, wheelbase l, wheelbase t, and center of gravity height h, calculate the load percentage at each location. This represents the percentage of front axle load. This represents the percentage of load on the rear axle. The percentage of load on the left side; This represents the percentage of load on the right side.

[0087] (2)

[0088] (3)

[0089] (4)

[0090] (5)

[0091] Furthermore, the vertical load on each wheel can be determined by referring to the following formulas (6)-(9) and combining the load percentage at each position. Wherein, F fl,z The vertical load when the wheel is the left front wheel; F fr,z F is the vertical load when the wheel is the right front wheel; rl,z The vertical load when the wheel is the left rear wheel; F rr,z The vertical load is when the wheel is the right rear wheel.

[0092] (6)

[0093] (7)

[0094] (8)

[0095] (9)

[0096] After determining the vertical load on each wheel, for each wheel, the actual ground adhesion force can be determined based on the current motor torque, vehicle attribute parameters, and motor braking parameters (such as the current motor torque and transmission ratio) in the braking-related parameters. Then, based on the proportional relationship between the actual ground adhesion force and the vertical load, the current adhesion coefficient of the wheel can be determined. The actual ground adhesion force is the force exerted by the ground on the wheel's contact patch.

[0097] S203, determine the target adhesion coefficient of the wheel based on the current slip ratio, current adhesion coefficient and historical adhesion coefficient of the wheel.

[0098] In one alternative implementation, for each wheel, parameters can be adjusted based on a determined coefficient of the wheel's current slip ratio; then, the coefficient adjustment parameters are used to adjust the coefficient difference between the wheel's current adhesion coefficient and its historical adhesion coefficient to obtain the wheel's target adhesion coefficient.

[0099] In another alternative implementation, the current slip ratio, current adhesion coefficient, and historical adhesion coefficient of the wheel can be input into a trained second coefficient determination model. The second coefficient determination model then outputs the target adhesion coefficient of the wheel based on the current slip ratio, current adhesion coefficient, and historical adhesion coefficient. The second coefficient determination model can be trained on a neural network model based on sample current slip ratios, sample current adhesion coefficients, sample historical adhesion coefficients, and corresponding sample target adhesion coefficients for each wheel in a sample vehicle.

[0100] In this embodiment, the current adhesion coefficient of the wheel is determined based on the braking correlation parameters and the vertical load of the wheel. Then, the target adhesion coefficient is determined based on the current slip ratio of the wheel, the current adhesion coefficient, and the historical adhesion coefficient, which ensures the accuracy of the target adhesion coefficient.

[0101] Based on the above embodiments, this application example provides an optional method for determining the current adhesion coefficient, such as... Figure 3 As shown, the specific steps include:

[0102] S301, based on the current motor torque, wheel rolling radius and transmission ratio of the wheel in the braking associated parameters, determine the ground adhesion driving force of the wheel.

[0103] Here, "current motor torque" refers to the actual torque in the motor at the current moment. "Ground adhesion driving force" is the driving force transmitted from the motor to the wheels through the braking system. "Gear ratio" is the ratio between the motor's input speed and the wheel's output speed. "Wheel rolling radius" is the radius of the wheel when it rolls.

[0104] In one alternative implementation, for each wheel, the current motor torque of that wheel can be processed based on the ratio between the transmission ratio and the wheel's rolling radius to obtain the ground adhesion driving force of that wheel. For example, the ratio between the transmission ratio i and the wheel's rolling radius r can be used, along with the current motor torque T, as shown in formula (10). motor The product of the two is used as the ground adhesion driving force F. drive .

[0105] (10)

[0106] S302. Based on the ground adhesion driving force and the wheel's angular acceleration, wheel rolling radius, and wheel moment of inertia in the braking-related parameters, determine the actual ground adhesion force of the wheel.

[0107] Angular acceleration is used to characterize how fast the wheel rotates. Actual ground adhesion is the longitudinal force exerted by the ground on the wheel contact area, propelling the vehicle forward.

[0108] In one alternative implementation, for each wheel, the inertia consumption parameter can be determined based on the wheel's angular acceleration, wheel rolling radius, and tire moment of inertia from the braking-related parameters; then, the difference between the ground adhesion driving force and the inertia consumption parameter is taken as the actual road surface adhesion force of the wheel. For example, referring to the following formula (11), the ratio between the product of angular acceleration a and tire moment of inertia I and the wheel rolling radius r can be taken as the inertia consumption parameter; then, the ground adhesion driving force F drive The difference between the actual road surface adhesion force F of the wheel and the consumption parameter is taken as the actual road surface adhesion force F of the wheel. x .

[0109] (11)

[0110] S303 determines the current adhesion coefficient of the wheel based on the actual ground adhesion and vertical load of the wheel.

[0111] In one alternative implementation, for each wheel, the target adhesion coefficient can be determined based on the ratio between the wheel's actual road surface adhesion and the vertical load. For example, a formula can be referenced. The actual road surface adhesion force F of the wheel is directly measured. x and vertical load F z The ratio between them is used as the target adhesion coefficient for the wheel. .

[0112] In this embodiment, the actual ground adhesion force of the wheel is determined based on the braking correlation parameters, and then the current adhesion coefficient of the wheel is determined by combining the actual ground adhesion force and the vertical load, which can ensure the accuracy of the determination of the current adhesion coefficient.

[0113] Based on the above embodiments, this application provides another optional method for determining the target adhesion coefficient, such as... Figure 4 As shown, the specific steps include:

[0114] S401, determine the target adhesion coefficient difference between the current adhesion coefficient and the historical adhesion coefficient of the wheel.

[0115] The so-called target adhesion coefficient difference is the difference between the current adhesion coefficient and the historical adhesion coefficient.

[0116] In one alternative implementation, for each wheel, a coefficient adjustment parameter can be used to adjust the difference between the current adhesion coefficient and the historical adhesion coefficient of that wheel to obtain a target adhesion coefficient difference. For example, refer to the formula... The current adhesion coefficient can be and historical adhesion coefficient The difference between them is taken as the target adhesion coefficient difference. .

[0117] S402, determine the first correction parameter based on the difference in the target adhesion coefficient and the first correspondence.

[0118] The so-called first correction parameter is the correction parameter determined based on the target adhesion coefficient difference. The first correspondence includes the correspondence between candidate adhesion coefficient differences and candidate correction parameters. The so-called candidate adhesion coefficient difference refers to the different adhesion coefficient differences that may exist. In this step, the so-called candidate correction parameter is the correction parameter corresponding to different candidate adhesion coefficient differences.

[0119] For example, the first correspondence can be determined by constructing a correspondence between the coefficient difference and the correction parameter based on the ground adhesion coefficient of the test vehicle under different working conditions (different vehicle speeds, loads, braking intensities, etc.) in different road conditions (dry asphalt, wet and slippery road surfaces, icy and snowy road surfaces, etc.). It is worth noting that the smaller the adhesion coefficient difference, the smaller the correction parameter.

[0120] In one alternative implementation, for each wheel, the target adhesion coefficient difference of that wheel can be used as an index to query the first correspondence to obtain the first correction parameter of that wheel. For example, the first correspondence can be presented in the form of Table 1 below. Table 1 is the first parameter correspondence table.

[0121] Table 1. First Parameter Correspondence Table

[0122]

[0123] For example, if the difference in the target adhesion coefficient is 0.5, the first correction parameter is 0.1.

[0124] S403, determine the second correction parameter based on the current slip ratio of the wheel and the second correspondence.

[0125] The so-called second correction parameter is the correction parameter determined based on the current slip ratio. The second correspondence includes the correspondence between candidate slip ratios and candidate correction parameters. A candidate slip ratio is any possible slip ratio. In this step, the candidate correction parameter is the correction parameter corresponding to different candidate slip ratios. It is worth noting that the candidate correction parameters in S402 and S403 are correction parameters in the same dimension, only their values ​​may differ.

[0126] For example, the second correspondence can be determined by constructing a correspondence between the vehicle slip ratio and the ground adhesion coefficient based on test data of the experimental vehicle under different working conditions (different vehicle speeds, loads, braking intensities, etc.) in different road conditions (dry asphalt, wet and slippery road surfaces, icy and snowy road surfaces, etc.). It is worth noting that when the slip ratio is small, the adhesion coefficient-slip ratio curve is in the deformation zone, and the adhesion coefficient calculated based on longitudinal and lateral forces has little reference value; therefore, the correction parameter is small. When the slip ratio is large (slipping), the adhesion coefficient calculated based on longitudinal and lateral forces has greater reference value; therefore, the correction parameter is large.

[0127] In one alternative implementation, for each wheel, the current slip ratio of that wheel can be used as an index to query the second correspondence to obtain the second correction parameter for that wheel. For example, the second correspondence can be presented in the form of Table 2 below. Table 2 is the second parameter correspondence table.

[0128] Table 2. Correspondence table of second parameters

[0129]

[0130] For example, with a current slip ratio of 10%, the second correction parameter is 0.4.

[0131] It is worth noting that the candidate correction parameters in Table 1 and Table 2 represent the same meaning; both are parameter values ​​used to correct the difference in the target adhesion coefficient. The only difference is that the candidate correction parameters in Table 1 are related to the adhesion coefficient difference, therefore, the candidate correction parameters determined by consulting Table 1 are the first correction parameters; the candidate correction parameters in Table 2 are related to the slip ratio, therefore, the candidate correction parameters determined by consulting Table 2 are the second correction parameters. Furthermore, because the information dimension associated with the candidate correction parameters in Table 1 (i.e., the adhesion coefficient difference dimension) is different from the information dimension associated with the candidate correction parameters in Table 2 (i.e., the slip ratio dimension), there are certain numerical differences between the candidate correction parameters in Table 1 and Table 2.

[0132] S404 uses the first correction parameter and the second correction parameter to correct the difference in the target adhesion coefficient.

[0133] In one alternative implementation, the first correction parameter and the second correction parameter can be used simultaneously and multiplied with the target adhesion coefficient difference to obtain the corrected target adhesion coefficient difference.

[0134] In another alternative implementation, the first correction parameter and the second correction parameter can be fused first, and then the fusion result can be used to correct the target adhesion coefficient difference, thereby obtaining the corrected target adhesion coefficient difference.

[0135] S405 uses the corrected target adhesion coefficient difference to adjust the historical adhesion coefficient, thus obtaining the target adhesion coefficient of the wheel.

[0136] In one alternative implementation, the corrected target adhesion coefficient difference can be used as an adjustment value to adjust the historical adhesion coefficient to obtain the target adhesion coefficient of the wheel. That is, the sum of the corrected target adhesion coefficient difference and the historical adhesion coefficient can be used as the target adhesion coefficient.

[0137] For example, you can refer to the following formula (12), first using the first correction parameter. Second correction parameter Difference in the target adhesion coefficient Correct the difference in the target adhesion coefficient and compare it with the historical adhesion coefficient. The sum of these values ​​serves as the target adhesion coefficient. .

[0138] (12)

[0139] In this embodiment, the target adhesion coefficient difference is corrected by using a first correction parameter determined based on the target adhesion coefficient difference and a second correction parameter determined based on the current slip ratio, and the historical adhesion coefficient is adjusted using the corrected parameters to obtain the target adhesion coefficient, thereby ensuring the accuracy of the target adhesion coefficient determination.

[0140] Based on the above embodiments, this application example provides an optional method for determining the target motor torque, such as... Figure 5 As shown, the specific steps include:

[0141] S501 determines the corrected slip ratio for each wheel based on the wheel's target adhesion coefficient and the current vehicle speed in the braking-related parameters.

[0142] The so-called corrected slip ratio is the slip ratio after speed correction.

[0143] In one alternative implementation, for each wheel, a first slip ratio can be determined based on the target adhesion coefficient of that wheel, and a second slip ratio can be determined based on the current vehicle speed in the braking associated parameters. The first slip ratio and the second slip ratio are then fused to obtain a corrected slip ratio.

[0144] In another alternative implementation, for each wheel, the current vehicle speed and the target adhesion coefficient of that wheel can be simultaneously input into a trained slip ratio determination model. The slip ratio determination model then outputs a corrected slip ratio based on the current vehicle speed and the target adhesion coefficient. The slip ratio determination model can be obtained by training a neural network model based on the sample vehicle's current speed, the sample target adhesion coefficients of each wheel, and the corresponding sample corrected slip ratios for each wheel.

[0145] S502 determines the feedforward control torque of the wheel based on the target adhesion coefficient and vertical load of the wheel, as well as the target lateral acceleration and wheel rolling radius in the braking associated parameters.

[0146] The target lateral acceleration refers to the vehicle's lateral acceleration at the current moment. It can be understood that the vehicle's lateral acceleration characterizes the change in tire longitudinal adhesion during vehicle movement. The feedforward control torque is, theoretically, the control torque fed back to the wheel motors.

[0147] In one alternative implementation, the change in the longitudinal adhesion of the tire at the current moment can be analyzed based on the target lateral acceleration, and the torque correction parameter corresponding to the change in the longitudinal adhesion of the tire can be obtained. Then, the vertical load can be adjusted based on the torque correction parameter, the target adhesion coefficient and the wheel rolling radius to obtain the feedforward control torque of the wheel.

[0148] In another alternative implementation, the target lateral acceleration, the vertical load on the wheel, the target adhesion coefficient, and the wheel rolling radius can be simultaneously input into a trained second torque determination model. The second torque determination model then outputs the feedforward control torque for the wheel based on the target lateral acceleration, vertical load, target adhesion coefficient, and wheel rolling radius. The second torque determination model can be trained on a neural network model using sample target lateral acceleration, sample vertical load on each wheel, sample target adhesion coefficient, sample wheel rolling radius, and the corresponding sample feedforward control torque from a sample vehicle.

[0149] S503 determines the wheel speed deviation value based on the corrected slip ratio, the current vehicle speed, and the current actual wheel speed.

[0150] The wheel speed deviation value is the difference between the current actual wheel speed and the target wheel speed. The target wheel speed is the wheel speed that the wheel should achieve under ideal motion conditions.

[0151] In one alternative implementation, the target wheel speed can be determined based on the current vehicle speed and the corrected slip ratio. For example, a formula can be referenced. According to the current vehicle speed v veh and corrected slip ratio S target,correct Calculate the target wheel speed v target .

[0152] Furthermore, the wheel speed deviation value can be determined based on the difference between the target wheel speed and the current actual wheel speed. For example, the formula v can be referenced. error =v target -v, uses the difference between the target wheel speed and the current actual wheel speed as the wheel speed deviation value v. error .

[0153] S504 determines the target motor torque of the wheel based on the feedforward control torque, wheel speed deviation value, and the actual control torque of the wheel in the braking correlation parameters.

[0154] The so-called actual control torque is the control torque in the wheel motor at the current moment.

[0155] In one alternative implementation, the wheel speed deviation value can be adjusted based on the torque difference between the feedforward control torque and the actual control torque of the wheel in the braking associated parameters, thereby obtaining the target motor torque of the wheel.

[0156] In another alternative implementation, the feedforward control torque, wheel speed deviation value, and actual control torque can be simultaneously input into a trained third torque determination model. The third torque determination model then outputs the target motor torque for the wheel based on the feedforward control torque, wheel speed deviation value, and actual control torque. The third torque determination model can be obtained by training a neural network model based on sample feedforward control torque, sample wheel speed deviation value, sample actual control torque, and the corresponding sample target motor torque of a sample vehicle.

[0157] In this embodiment, the feedforward control torque is determined based on the target adhesion coefficient, vertical load, and target lateral acceleration. Then, the target motor torque of the wheel is determined by combining the feedforward control torque, wheel speed deviation value, and actual control torque, which ensures the accuracy of the target motor torque determination.

[0158] Based on the above embodiments, this application example provides an optional method for determining the corrected slip ratio, such as... Figure 6 As shown, the specific steps include:

[0159] S601, determine the target slip ratio based on the target adhesion coefficient of the wheel and the third correspondence.

[0160] The target slip ratio is the slip ratio determined based on the target adhesion coefficient. The third correspondence includes the relationship between candidate adhesion coefficients and candidate slip ratios. Candidate adhesion coefficients are the possible surface adhesion coefficients at various locations. Candidate slip ratios are the slip ratios corresponding to different candidate adhesion coefficients.

[0161] For example, the third correspondence can be determined by inferring the adhesion coefficient based on test data such as vehicle slip ratio, vehicle braking force, and road adhesion coefficient of the test vehicle under different working conditions (different vehicle speed, load, braking intensity, etc.) in different road conditions (dry asphalt, wet and slippery road surface, icy and snowy road surface, etc.), and then fitting the inferred coefficient with the vehicle slip ratio to obtain the third correspondence.

[0162] In one alternative implementation, the target adhesion coefficient can be used as an index to query the third correspondence to obtain the target slip ratio. For example, the third correspondence can be presented in the form of Table 3 below. Table 3 is the first slip ratio correspondence table.

[0163] Table 3. Correspondence Table for First Slip Ratio

[0164]

[0165] For example, with a target adhesion coefficient of 0.1, the target slip ratio is 22%.

[0166] S602, determine the target offset based on the fourth correspondence and the current vehicle speed in the braking association parameters.

[0167] The target offset is the offset of the slip ratio at the current vehicle speed. The fourth correspondence includes the correspondence between candidate vehicle speeds and candidate offsets. Candidate vehicle speeds are all possible vehicle speeds. Candidate offsets are the offsets of the slip ratios at different vehicle speeds.

[0168] For example, the fourth correspondence can be determined by fitting the vehicle speed with the slip ratio offset under different working conditions (different vehicle speeds, loads, braking intensities, etc.) of the test vehicle in different road conditions (dry asphalt, wet and slippery road surface, icy and snowy road surface, etc.) to obtain the fourth correspondence.

[0169] In one alternative implementation, the current vehicle speed can be used as an index to query the fourth correspondence to obtain the target offset. For example, the fourth correspondence can be presented in the form of Table 4 below. Table 4 is the offset correspondence table.

[0170] Table 4 Offset Correspondence Table

[0171]

[0172] For example, at a current vehicle speed of 2 km / h, the target slip ratio is 7%.

[0173] S603, determine the corrected slip ratio based on the target slip ratio and the target offset.

[0174] In one alternative implementation, the target slip ratio and the target offset can be fused to obtain the corrected slip ratio. For example, refer to formula S. target,correct =S target,init +S target,offet Target slip ratio S target,init and target offset S target,offet The sum of these is used as the corrected slip ratio S. target,correct .

[0175] In this embodiment of the application, the corrected slip ratio is determined by using the target slip ratio determined based on the target adhesion coefficient and the target offset determined by the current vehicle speed, which can ensure the accuracy of the corrected slip ratio determination.

[0176] Based on the above embodiments, this application provides an optional method for determining the feedforward control torque. Specifically, the target longitudinal force factor is determined according to the longitudinal force factor correspondence and the target lateral acceleration in the braking correlation parameters; the feedforward control torque of the wheel is determined according to the target longitudinal force factor, vertical load, target adhesion coefficient and wheel rolling radius in the braking correlation parameters.

[0177] The longitudinal force factor correspondence includes the relationship between candidate lateral accelerations and candidate longitudinal force factors. Candidate lateral accelerations are the possible lateral acceleration values, and candidate longitudinal force factors are the longitudinal force factors corresponding to each lateral acceleration value. The longitudinal force factor is the correction parameter used in the control system to compensate for the influence of lateral acceleration on the longitudinal force. The target longitudinal force factor is the correction parameter used at the current moment to compensate for the influence of lateral acceleration on the longitudinal force. It is worth noting that in the vehicle coordinate system, the direction of vehicle travel is the longitudinal axis (X-axis), and lateral movement is the lateral Y-axis.

[0178] For example, the longitudinal force factor correspondence can be determined by fitting the vehicle operation data such as lateral acceleration, longitudinal force, vertical load, sideslip angle, and slip ratio of the test vehicle under different working conditions (different vehicle speeds, steering angles, braking intensities, road surface types, load distribution conditions, etc.) to obtain the longitudinal force factor correspondence between lateral acceleration and longitudinal force factor.

[0179] In an alternative implementation, the following formula (13) can be used as a reference, based on the current vehicle speed v. veh Front wheel steering angle (left front wheel steering angle) Right front wheel steering angle ), wheelbase l, determine the target lateral acceleration a y,target .

[0180] (13)

[0181] Furthermore, the target lateral acceleration can be used as an index to query the longitudinal force factor correspondence to obtain the target longitudinal force factor. The longitudinal force factor correspondence can be presented in the form of Table 5 below. Table 5 is the longitudinal force factor correspondence table.

[0182] Table 5. Correspondence Table of Longitudinal Force Factors

[0183]

[0184] For example, when the target's lateral acceleration is 3 m / s / s, the target's longitudinal force factor is 0.9.

[0185] In one alternative implementation, after determining the target longitudinal force factor, a first torque adjustment parameter can be determined using the target longitudinal force factor, the target adhesion coefficient, and the wheel rolling radius. Then, the vertical load is adjusted using the first torque adjustment parameter to obtain the wheel's feedforward control torque. For example, refer to the formula... Directly apply the vertical load F z Target adhesion coefficient Wheel rolling radius r and target longitudinal force factor f correct The product of these values ​​serves as the feedforward control torque T for the wheels. feedforward .

[0186] In this embodiment, by determining the target longitudinal force factor based on the target lateral acceleration, and by determining the wheel feedforward control torque based on the target longitudinal force factor, vertical load, target adhesion coefficient, and wheel rolling radius, the accuracy of the feedforward control torque determination can be guaranteed.

[0187] Based on the above embodiments, this application provides another optional method for determining the target motor torque, such as... Figure 7 As shown, it specifically includes the following:

[0188] S701 determines the basic correction torque of the wheel based on the difference between the actual control torque of the wheel and the feedforward control torque in the braking correlation parameters.

[0189] The so-called basic correction torque is the torque difference between the actual control torque and the feedforward control torque.

[0190] In one alternative implementation, a preset second torque adjustment parameter can be used to adjust the difference between the actual control torque of the wheel at the current moment and the feedforward control torque to obtain the basic correction torque.

[0191] In another alternative implementation, reference can be made to formula T. feedback,base =T actual -T feedforward The actual control torque T of the wheel at the current moment. actual With feedforward control torque T feedforward The difference is directly used as the base correction torque T for the target wheel. feedback,base .

[0192] S702 uses a controller adjustment coefficient to fuse the wheel speed deviation value and the basic correction torque to obtain the wheel feedforward correction torque.

[0193] The controller adjustment coefficient is a coefficient used to adjust the controller's response speed, stability, and steady-state error; it can be a proportional-integral-derivative (PID) coefficient. The feedforward correction torque is the adjusted control torque.

[0194] In one alternative implementation, a controller adjustment coefficient can be used to adjust the wheel speed deviation value to obtain a torque correction value, and the basic correction torque can be adjusted using the torque correction value to obtain the wheel feedforward correction torque.

[0195] For example, the following formula (14) can be used, employing the PID coefficient (proportional coefficient K). p Integral coefficient K i and differential coefficient K d ), for wheel speed deviation value v error Adjustments are made, and the sum of the adjusted torque correction value and the basic correction torque is used as the feedforward correction torque T. feedback .in, This represents the rate of change of angle corresponding to the wheel speed deviation value.

[0196] (14)

[0197] Furthermore, to ensure the reliability of the PID coefficients, they can be calibrated based on the current vehicle speed and the current road surface adhesion coefficient. ,in, This is the proportional coefficient at the current vehicle speed. This is the proportional coefficient under the current road surface adhesion coefficient; ,in, The integral coefficient at the current vehicle speed. This is the integral coefficient under the current road surface adhesion coefficient; ,in, The differential coefficients at the current vehicle speed are... This is the differential coefficient under the current road surface adhesion coefficient.

[0198] The PID coefficients at each vehicle speed can be presented in the form of Table 6, which is a table showing the PID correspondence for each vehicle speed.

[0199] Table 6 Vehicle Speed ​​PID Correspondence Table

[0200]

[0201] The PID coefficients under the road surface adhesion coefficient can be presented in the form of Table 7, where Table 7 is the PID correspondence table for the road surface adhesion coefficient.

[0202] Table 7. Correspondence table of road surface adhesion coefficient (PID).

[0203]

[0204] S703 determines the target motor torque of the wheel based on the feedforward control torque, the feedforward correction torque, the wheel rolling radius, and the wheel transmission ratio.

[0205] In one alternative implementation, the final torque can be determined based on the feedforward control torque and the feedforward correction torque; then, the final torque is adjusted using the ratio between the wheel rolling radius and the wheel transmission ratio to obtain the target motor torque of the wheel.

[0206] For example, the following formula (15) can be used to adjust the feedforward correction torque T by using the ratio between the wheel rolling radius r and the transmission ratio i. feedback With feedforward control torque T feedforward The sum is adjusted to obtain the target motor torque T. s .

[0207] (15)

[0208] In this embodiment, by using a controller adjustment coefficient, the wheel speed deviation value and the basic correction torque are fused to obtain the feedforward correction torque. Based on the feedforward control torque, the feedforward correction torque, the wheel rolling radius and the transmission ratio, the target motor torque is determined, which can ensure the accuracy of the target motor torque determination.

[0209] Based on the above embodiments, this application example provides an optional method for determining the current actual wheel speed, such as... Figure 8 As shown, it specifically includes the following:

[0210] S801, based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel, determines the current reference wheel speed of the first wheel based on the prediction of each second wheel.

[0211] The so-called current reference wheel speed is the predicted reference wheel speed of the first wheel based on the current actual wheel speed of the second wheel. It is worth noting that the current actual wheel speed of each second wheel can predict the current reference wheel speed of one first wheel. For example, the current reference wheel speeds of three first wheels can be predicted based on the current actual wheel speeds of the other three second wheels.

[0212] In one alternative implementation, for each second wheel, a calculation strategy for calculating the current reference wheel speed can be determined first based on the wheel positions of the first and second wheels. Then, target parameters are selected from the vehicle's braking-related parameters, including front wheel steering angle, yaw rate, and track width, according to the calculation parameters required by the calculation strategy. Further, the target parameters and the current actual wheel speed of the second wheel can be substituted into the selected calculation strategy to calculate the current reference wheel speed of the first wheel predicted based on the second wheel.

[0213] For example, when the first wheel is positioned as the left front wheel fl, the following formulas (16)-(18) can be used to calculate the position based on the left front wheel's turning angle. Right front wheel steering angle Wheelbase t and yaw rate Determine the current reference wheel speed v of the left front wheel based on the prediction of the right front wheel fr. fl,fr The current reference wheel speed v of the left front wheel fl is predicted based on the left rear wheel rl. fl,rl And the current reference wheel speed v of the left front wheel fl predicted based on the right rear wheel rr. fl,rr Among them, v fr v represents the current actual wheel speed of the right front wheel. rl v represents the current actual wheel speed of the right front wheel. rr This represents the current actual wheel speed of the right rear wheel.

[0214] (16)

[0215] (17)

[0216] (18)

[0217] When the first wheel is positioned as the right front wheel (fr), the following formulas (19)-(21) can be used as a reference, depending on the turning angle of the left front wheel. Right front wheel steering angle Wheelbase t and yaw rate Determine the current reference wheel speed v of the right front wheel fr based on the prediction of the left front wheel fl. fr,fl The current reference wheel speed v of the right front wheel fr is predicted based on the left rear wheel rl. fr,rl And the current reference wheel speed v of the right front wheel fr predicted based on the right rear wheel rr. fr,rr .

[0218] (19)

[0219] (20)

[0220] (twenty one)

[0221] When the first wheel is positioned as the left rear wheel rl, the following formulas (22)-(24) can be used as a reference, depending on the left front wheel turning angle. Right front wheel steering angle Wheelbase t and yaw rate Determine the current reference wheel speed v of the left rear wheel rl based on the prediction of the left front wheel fl. rl,fl The current reference wheel speed v of the left rear wheel rl is predicted based on the right front wheel fr. rl,fr And the current reference wheel speed v of the left rear wheel rl predicted based on the right rear wheel rr. rl,rr .

[0222] (twenty two)

[0223] (twenty three)

[0224] (twenty four)

[0225] When the first wheel is positioned as the right rear wheel (rr), the following formulas (25)-(27) can be used as a reference, depending on the turning angle of the left front wheel. Right front wheel steering angle Wheelbase t and yaw rate Determine the current reference wheel speed v of the right rear wheel based on the prediction of the left front wheel fl. rr,fl The current reference wheel speed v of the right rear wheel rr is predicted based on the right front wheel fr. rr,fr And the current reference wheel speed v of the right rear wheel rr predicted based on the left rear wheel rl. rr,rl .

[0226] (25)

[0227] (26)

[0228] (27)

[0229] S802, based on the braking correlation parameters and the current reference wheel speeds, determines the current actual wheel speed of the first wheel.

[0230] The first step, for each wheel, is to determine the ground adhesion driving force and vertical load based on braking-related parameters. Then, the ratio between the ground adhesion driving force and the vertical load is taken as the ideal braking coefficient for that wheel. The ideal braking coefficient characterizes the braking dynamics at each wheel end; the larger the ideal braking coefficient, the more severe the dynamics at the wheel end. For example, the formula can be referenced. The ground adhesion driving force F drive and vertical load F Z The ratio between them is used as the ideal braking coefficient for that wheel. .

[0231] The second step involves using the difference between the ideal braking coefficient of the second wheel and the ideal braking coefficient of the first wheel as the target coefficient difference parameter for each second wheel. This target coefficient difference parameter characterizes the difference between the ideal braking coefficients. For example, when the first wheel is the left front wheel (fl), the target coefficient difference parameter for the left rear wheel (fr) can be calculated using the following formula (28). The target coefficient difference parameter for the left rear wheel; The ideal braking coefficient for the left rear wheel; This is the ideal braking coefficient for the left front wheel.

[0232] (28)

[0233] The third step involves determining the wheel speed reference weight for each second wheel based on the correspondence between the target coefficient difference parameter and the first weight. The first weight correspondence includes the correspondence between candidate coefficient difference parameters and candidate reference weights. Candidate coefficient difference parameters are the various possible coefficient difference parameters, and candidate reference weights are the wheel speed reference weights under different coefficient difference parameters. The wheel speed reference weight is the reference weight under the target coefficient difference parameter and is also the basic weight value used when weighting the current reference wheel speed associated with the second wheel. It is worth noting that the larger the target coefficient difference parameter between the two wheels, the greater the difference in the wheel-end working conditions between the two wheels; therefore, the lower the reliability of the calculated current reference wheel speed.

[0234] For example, the first weight correspondence can be determined by inferring the ideal braking coefficient of each wheel based on test data of vehicle braking force and vertical load under different working conditions (different vehicle speeds, loads, braking intensities, etc.) of the test vehicle in different road conditions (dry asphalt, wet and slippery road surface, icy and snowy road surface, etc.), and then processing the difference between the inferred ideal braking coefficients of each wheel and the difference between the actual wheel speed to obtain the first weight correspondence.

[0235] In one alternative implementation, for each second wheel, the target coefficient difference parameter of that second wheel can be used as an index to query the first weight correspondence to obtain the wheel speed reference weight of that second wheel. For example, the first weight correspondence can be presented in the form of Table 8 below. Table 8 is a third parameter correspondence table.

[0236] Table 8. Correspondence Table of Third Parameter

[0237]

[0238] The fourth step is to determine the wheel speed constraint weight for each second wheel based on the current slip ratio and the correspondence between the second wheel and the second weight.

[0239] The second weight correspondence includes the relationship between candidate slip ratios and candidate constraint weights. A candidate slip ratio refers to any possible slip ratio. A candidate constraint weight is the constraint weight corresponding to different candidate slip ratios. The wheel speed constraint weight is the constraint weight under the current slip ratio. It is worth noting that the smaller the slip ratio, the more normal the wheel's motion; in this case, the current reference wheel speed is more meaningful. Conversely, the larger the slip ratio, the less meaningful the current reference wheel speed is.

[0240] For example, the second weight correspondence can be determined by inferring the relationship between vehicle slip ratio and wheel speed based on test data of the test vehicle under different working conditions (different vehicle speed, load, braking intensity, etc.) in different road conditions (dry asphalt, wet and slippery road surface, icy and snowy road surface, etc.), and then generating the second weight correspondence based on the relationship.

[0241] In one alternative implementation, for each second wheel, the current slip ratio of that second wheel can be used as an index to query the second weight correspondence to obtain the wheel speed constraint weight of that second wheel. For example, the second weight correspondence can be presented in the form of Table 9 below. Table 9 is the second slip ratio correspondence table.

[0242] Table 9. Correspondence Table for Second Slip Ratio

[0243]

[0244] The fifth step is to determine the target wheel speed weight for each second wheel based on its wheel speed reference weight and wheel speed constraint weight.

[0245] In one optional implementation, a target wheel speed weight can be determined from the wheel speed reference weight and the wheel speed constraint weight based on the relationship between them. For example, for each second wheel, if the wheel speed reference weight is less than the wheel speed constraint weight, the wheel speed reference weight can be used as the target wheel speed weight for that second wheel; if the wheel speed reference weight is greater than or equal to the wheel speed constraint weight, the wheel speed constraint weight can be used as the target wheel speed weight for that second wheel.

[0246] The sixth step is to determine the current actual wheel speed of the first wheel based on the target wheel speed weights of each second wheel and the corresponding current reference wheel speed.

[0247] In one alternative implementation, the target wheel speed weights of each second wheel can be used to weight the corresponding current reference wheel speeds to obtain the current actual wheel speed of the first wheel. For example, taking the left front wheel fl as the first wheel, referring to the following formula (29), the target wheel speed weights of the right front wheel fr, the left rear wheel rl, and the right rear wheel rr are used to weight the corresponding current reference wheel speeds to obtain the current actual wheel speed v of the left front wheel fl. fl .

[0248] (29)

[0249] Among them, v fl,fr This is the current reference wheel speed associated with the right front wheel; The target wheel speed weight for the right front wheel; v fl,rl The current reference wheel speed associated with the left rear wheel; The target wheel speed weight associated with the left rear wheel; v fl,rr The current reference wheel speed associated with the right rear wheel; The target wheel speed weight associated with the right rear wheel.

[0250] In this embodiment, by determining the current actual wheel speed of the first wheel based on the braking correlation parameters and each current reference wheel speed, the calculated current actual wheel speed can be matched with each of the second wheels, thereby ensuring the accuracy of the current actual wheel speed of the first wheel.

[0251] Based on the same inventive concept, this application also provides a vehicle, which includes a vehicle controller, and braking systems and sensors corresponding to each wheel. The vehicle controller is used to control the vehicle's operating state; the braking systems corresponding to each wheel are used to control the movement of the corresponding wheel.

[0252] Based on this, the vehicle wheel control method is as follows: when the vehicle controller detects a lack of wheel speed in the first wheel, it obtains the current actual wheel speed of each second wheel at the current moment through the sensors corresponding to the second wheels; the vehicle controller determines the current actual wheel speed of the first wheel based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel; the vehicle controller determines the target adhesion coefficient of each wheel based on the braking correlation parameters, the current actual wheel speed of each wheel, and the historical adhesion coefficient; the vehicle controller determines the target motor torque of each wheel based on the braking correlation parameters, the target adhesion coefficient of each wheel, and the current actual wheel speed, and sends the target motor torque of each wheel to the braking system of the corresponding wheel; the braking system corresponding to each wheel controls the operation of the corresponding wheel based on the target motor torque of the wheel.

[0253] Each second wheel is one of the wheels of the vehicle other than the first wheel.

[0254] For example, you can refer to Figure 9 The diagram shows the vehicle structure. The wheel speed sensors on all four wheels transmit the collected current wheel speeds to the vehicle controller in real time. If the vehicle controller detects a missing wheel speed from the first wheel, it can first obtain the current actual wheel speeds of the second wheels using the sensors on the second wheels.

[0255] Subsequently, the vehicle controller can refer to the steps in the above embodiments to determine the current actual wheel speed of the first wheel based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel, and determine the target adhesion coefficient of each wheel based on the braking correlation parameters, the current actual wheel speed of each wheel, and the historical adhesion coefficient.

[0256] Furthermore, the vehicle controller determines the target motor torque for each wheel based on braking-related parameters, the target adhesion coefficient of each wheel, and the current actual wheel speed, and sends the target motor torque for each wheel to the corresponding wheel's braking system. Upon receiving the target motor torque, the braking system for each wheel can control the operation of that wheel accordingly.

[0257] Figure 10 This is a flowchart illustrating a vehicle control method in another embodiment. Based on the above embodiments, this embodiment provides an optional example of a vehicle control method. (Combined with...) Figure 10 The specific implementation process is as follows:

[0258] S1001, when the wheel speed of the first wheel in the vehicle is detected to be missing, the current actual wheel speed of the first wheel is determined based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel.

[0259] Each second wheel is one of the wheels of the vehicle other than the first wheel.

[0260] Optionally, based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel, the current reference wheel speed of the first wheel, predicted based on each second wheel, is determined; and based on the braking correlation parameters and each current reference wheel speed, the current actual wheel speed of the first wheel is determined.

[0261] S1002, for each wheel, determine the current slip ratio of the wheel based on the current actual wheel speed and the current vehicle speed in the braking-related parameters, and determine the ground adhesion driving force of the wheel based on the current motor torque, wheel rolling radius and transmission ratio of the wheel in the braking-related parameters.

[0262] S1003, for each wheel, the actual ground adhesion force of the wheel is determined based on the ground adhesion driving force and the wheel's angular acceleration, rolling radius, and moment of inertia in the braking-related parameters.

[0263] S1004: For each wheel, determine the current adhesion coefficient of the wheel based on the actual ground adhesion force and vertical load of the wheel, and determine the target adhesion coefficient of the wheel based on the current slip ratio, current adhesion coefficient and historical adhesion coefficient.

[0264] Optionally, the target adhesion coefficient difference between the current adhesion coefficient and the historical adhesion coefficient of the wheel is determined; a first correction parameter is determined based on the target adhesion coefficient difference and a first correspondence; wherein the first correspondence includes the correspondence between candidate adhesion coefficient differences and candidate correction parameters; a second correction parameter is determined based on the current slip ratio of the wheel and a second correspondence; wherein the second correspondence includes the correspondence between candidate slip ratio and candidate correction parameters; the target adhesion coefficient difference is corrected using the first correction parameter and the second correction parameter; and the historical adhesion coefficient is adjusted using the corrected target adhesion coefficient difference to obtain the target adhesion coefficient of the wheel.

[0265] S1005 determines the target motor torque for each wheel based on the braking correlation parameters, the target adhesion coefficient of each wheel, and the current actual wheel speed, and controls the operation of the corresponding wheel based on the target motor torque of each wheel.

[0266] Optionally, for each wheel, a target slip ratio is determined based on the wheel's target adhesion coefficient and a third correspondence; wherein the third correspondence includes the correspondence between candidate adhesion coefficients and candidate slip ratios; a target offset is determined based on a fourth correspondence and the current vehicle speed in the braking correlation parameters; wherein the fourth correspondence includes the correspondence between candidate vehicle speeds and candidate offsets; and a corrected slip ratio is determined based on the target slip ratio and the target offset.

[0267] Furthermore, the target longitudinal force factor is determined based on the longitudinal force factor correspondence and the target lateral acceleration in the braking correlation parameters; wherein, the longitudinal force factor correspondence includes the correspondence between candidate lateral acceleration and candidate longitudinal force factor; and the wheel feedforward control torque is determined based on the target longitudinal force factor, vertical load, target adhesion coefficient and wheel rolling radius in the braking correlation parameters.

[0268] Furthermore, the wheel speed deviation value is determined based on the corrected slip ratio, the current vehicle speed, and the current actual wheel speed; the basic corrected torque of the wheel is determined based on the difference between the actual control torque of the wheel in the braking correlation parameters and the feedforward control torque; the wheel speed deviation value and the basic corrected torque are fused using the controller adjustment coefficient to obtain the feedforward corrected torque of the wheel; the target motor torque of the wheel is determined based on the feedforward control torque, the feedforward corrected torque, the wheel rolling radius, and the wheel transmission ratio.

[0269] The specific processes of S1001-S1005 described above can be found in the description of the above method embodiments. Their implementation principles and technical effects are similar, and will not be repeated here.

[0270] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated 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 steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0271] Based on the same inventive concept, this application also provides a vehicle control device for implementing the vehicle control method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations in one or more vehicle control device embodiments provided below can be found in the limitations of the vehicle control method described above, and will not be repeated here.

[0272] In one exemplary embodiment, such as Figure 11 As shown, a vehicle control device 1 is provided, including: a wheel speed determination module 10, a coefficient determination module 20, and a vehicle control module 30, wherein:

[0273] The wheel speed determination module 10 is used to determine the current actual wheel speed of the first wheel based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel when the wheel speed of the first wheel in the vehicle is detected to be missing; wherein, each second wheel is the wheel of the vehicle other than the first wheel.

[0274] The coefficient determination module 20 is used to determine the target adhesion coefficient of each wheel based on the braking correlation parameters, the current actual wheel speed and historical adhesion coefficient of each wheel.

[0275] The vehicle control module 30 is used to determine the target motor torque of each wheel based on the braking correlation parameters, the target adhesion coefficient of each wheel and the current actual wheel speed, and control the operation of the corresponding wheel based on the target motor torque of each wheel.

[0276] In an exemplary embodiment, the coefficient determination module 20 is specifically used for:

[0277] For each wheel, the current slip ratio is determined based on the wheel's current actual wheel speed and the current vehicle speed in the braking-related parameters; the current adhesion coefficient is determined based on the braking-related parameters and the wheel's vertical load; and the target adhesion coefficient is determined based on the wheel's current slip ratio, current adhesion coefficient, and historical adhesion coefficient.

[0278] In an exemplary embodiment, the coefficient determination module 20 is further configured to:

[0279] Based on the current motor torque, wheel rolling radius, and transmission ratio of the wheel in the braking-related parameters, determine the ground adhesion driving force of the wheel; based on the ground adhesion driving force, as well as the wheel angular acceleration, wheel rolling radius, and wheel moment of inertia in the braking-related parameters, determine the actual ground adhesion force of the wheel; based on the actual ground adhesion force of the wheel and the vertical load, determine the current adhesion coefficient of the wheel.

[0280] In an exemplary embodiment, the coefficient determination module 20 is further configured to:

[0281] The process involves: determining the target adhesion coefficient difference between the current and historical adhesion coefficients of the wheel; determining a first correction parameter based on the target adhesion coefficient difference and a first correspondence, wherein the first correspondence includes the correspondence between candidate adhesion coefficient differences and candidate correction parameters; determining a second correction parameter based on the current slip ratio of the wheel and a second correspondence, wherein the second correspondence includes the correspondence between candidate slip ratios and candidate correction parameters; correcting the target adhesion coefficient difference using the first and second correction parameters; and adjusting the historical adhesion coefficient using the corrected target adhesion coefficient difference to obtain the target adhesion coefficient of the wheel.

[0282] In one exemplary embodiment, the vehicle control module 30 is specifically used for:

[0283] For each wheel, the corrected slip ratio is determined based on the wheel's target adhesion coefficient and the current vehicle speed in the braking-related parameters; the feedforward control torque of the wheel is determined based on the wheel's target adhesion coefficient and vertical load, as well as the target lateral acceleration and wheel rolling radius in the braking-related parameters; the wheel speed deviation value is determined based on the corrected slip ratio, the current vehicle speed, and the current actual wheel speed; and the target motor torque of the wheel is determined based on the feedforward control torque, the wheel speed deviation value, and the actual control torque of the wheel in the braking-related parameters.

[0284] In one exemplary embodiment, the vehicle control module 30 is further configured to:

[0285] The target slip ratio is determined based on the target adhesion coefficient of the wheel and the third correspondence; wherein the third correspondence includes the correspondence between candidate adhesion coefficients and candidate slip ratios; the target offset is determined based on the fourth correspondence and the current vehicle speed in the braking correlation parameters; wherein the fourth correspondence includes the correspondence between candidate vehicle speeds and candidate offsets; and the corrected slip ratio is determined based on the target slip ratio and the target offset.

[0286] In one exemplary embodiment, the vehicle control module 30 is further configured to:

[0287] The target longitudinal force factor is determined based on the longitudinal force factor correspondence and the target lateral acceleration in the braking correlation parameters; wherein, the longitudinal force factor correspondence includes the correspondence between candidate lateral acceleration and candidate longitudinal force factor; the wheel feedforward control torque is determined based on the target longitudinal force factor, vertical load, target adhesion coefficient and wheel rolling radius in the braking correlation parameters.

[0288] In one exemplary embodiment, the vehicle control module 30 is further configured to:

[0289] Based on the difference between the actual control torque of the wheel and the feedforward control torque in the braking correlation parameters, the basic correction torque of the wheel is determined; the wheel speed deviation value and the basic correction torque are fused using the controller adjustment coefficient to obtain the feedforward correction torque of the wheel; the target motor torque of the wheel is determined based on the feedforward control torque, the feedforward correction torque, the wheel rolling radius and the wheel transmission ratio.

[0290] In one exemplary embodiment, the wheel speed determination module 10 is specifically used for:

[0291] Based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel, determine the current reference wheel speed of the first wheel based on the prediction of each second wheel; based on the braking correlation parameters and each current reference wheel speed, determine the current actual wheel speed of the first wheel.

[0292] Each module in the aforementioned vehicle control device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0293] In one exemplary embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be as follows: Figure 12 As shown, the computer device includes a processor, memory, input / output interface, communication interface, display unit, and input device. The processor, memory, and input / output interface are connected via a system bus, and the communication interface, display unit, and input device are also connected to the system bus via the input / output interface. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The input / output interface is used for exchanging information between the processor and external devices. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, Near Field Communication (NFC), or other technologies. When the computer program is executed by the processor, it implements a vehicle control method. The display unit is used to form a visually visible image and can be a display screen, projection device, or virtual reality imaging device. The display screen can be an LCD screen or an e-ink screen. The input device of the computer device can be a touch layer covering the display screen, or buttons, trackballs, or touchpads set on the casing of the computer device, or external keyboards, touchpads, or mice, etc.

[0294] Those skilled in the art will understand that Figure 12 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0295] In one embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0296] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the steps in the above method embodiments.

[0297] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0298] It should be noted that the data involved in this application (including but not limited to data related to vehicle operation) is all data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0299] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0300] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0301] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A vehicle control method, characterized in that, The method includes: If a missing wheel speed is detected in the first wheel of the vehicle, the current actual wheel speed of the first wheel is determined based on the braking correlation parameters of the vehicle and the current actual wheel speed of each second wheel; wherein, each second wheel is a wheel of the vehicle other than the first wheel. For each wheel, the current slip ratio of the wheel is determined based on the current actual wheel speed and the current vehicle speed in the braking correlation parameters, and the current adhesion coefficient of the wheel is determined based on the braking correlation parameters and the vertical load of the wheel; and the target adhesion coefficient of the wheel is determined based on the current slip ratio, the current adhesion coefficient and the historical adhesion coefficient. Based on the braking correlation parameters, the target adhesion coefficient of each wheel and the current actual wheel speed, the target motor torque of each wheel is determined, and the operation of the corresponding wheel is controlled according to the target motor torque of each wheel.

2. The method according to claim 1, characterized in that, Determining the current coefficient of adhesion of the wheel based on the braking correlation parameters and the vertical load on the wheel includes: The ground adhesion driving force of the wheel is determined based on the current motor torque, wheel rolling radius and transmission ratio of the wheel in the braking correlation parameters. The actual ground adhesion force of the wheel is determined based on the ground adhesion driving force and the angular acceleration, rolling radius, and moment of inertia of the wheel in the braking associated parameters. The current adhesion coefficient of the wheel is determined based on the actual ground adhesion and vertical load of the wheel.

3. The method according to claim 1, characterized in that, Determining the target adhesion coefficient of the wheel based on its current slip ratio, current adhesion coefficient, and historical adhesion coefficient includes: Determine the target adhesion coefficient difference between the current adhesion coefficient and the historical adhesion coefficient of the wheel; A first correction parameter is determined based on the target adhesion coefficient difference and the first correspondence; wherein, the first correspondence includes the correspondence between candidate adhesion coefficient differences and candidate correction parameters; A second correction parameter is determined based on the current slip ratio of the wheel and the second correspondence; wherein, the second correspondence includes the correspondence between candidate slip ratios and candidate correction parameters; The difference in the target adhesion coefficient is corrected using the first correction parameter and the second correction parameter; The historical adhesion coefficient is adjusted using the corrected target adhesion coefficient difference to obtain the target adhesion coefficient of the wheel.

4. The method according to claim 1, characterized in that, The step of determining the target motor torque for each wheel based on the braking correlation parameters, the target adhesion coefficient of each wheel, and the current actual wheel speed includes: For each wheel, a corrected slip ratio is determined based on the target adhesion coefficient of the wheel and the current vehicle speed in the braking correlation parameters. The feedforward control torque of the wheel is determined based on the target adhesion coefficient and vertical load of the wheel, as well as the target lateral acceleration and wheel rolling radius in the braking correlation parameters. The wheel speed deviation value is determined based on the corrected slip ratio, the current vehicle speed, and the current actual wheel speed. The target motor torque of the wheel is determined based on the feedforward control torque, the wheel speed deviation value, and the actual control torque of the wheel in the braking correlation parameters.

5. The method according to claim 4, characterized in that, The step of determining the corrected slip ratio based on the target adhesion coefficient of the wheel and the current vehicle speed in the braking correlation parameters includes: The target slip ratio is determined based on the target adhesion coefficient of the wheel and the third correspondence relationship; wherein, the third correspondence relationship includes the correspondence relationship between candidate adhesion coefficients and candidate slip ratios; The target offset is determined based on the fourth correspondence and the current vehicle speed in the braking correlation parameters; wherein, the fourth correspondence includes the correspondence between candidate vehicle speeds and candidate offsets; The corrected slip ratio is determined based on the target slip ratio and the target offset.

6. The method according to claim 4, characterized in that, The step of determining the feedforward control torque of the wheel based on the target adhesion coefficient and vertical load of the wheel, and the target lateral acceleration in the braking correlation parameters, includes: The target longitudinal force factor is determined based on the longitudinal force factor correspondence and the target lateral acceleration in the braking correlation parameters; wherein, the longitudinal force factor correspondence includes the correspondence between candidate lateral acceleration and candidate longitudinal force factor; The feedforward control torque of the wheel is determined based on the target longitudinal force factor, the vertical load, the target adhesion coefficient, and the wheel rolling radius of the wheel in the braking correlation parameters.

7. The method according to claim 4, characterized in that, The step of determining the target motor torque of the wheel based on the feedforward control torque, the wheel speed deviation value, and the actual control torque of the wheel in the braking correlation parameters includes: The base correction torque of the wheel is determined based on the difference between the actual control torque of the wheel in the braking correlation parameters and the feedforward control torque. The wheel speed deviation value and the basic correction torque are fused using the controller adjustment coefficient to obtain the feedforward correction torque of the wheel; The target motor torque of the wheel is determined based on the feedforward control torque, the feedforward correction torque, the wheel rolling radius, and the wheel transmission ratio.

8. The method according to claim 1, characterized in that, Determining the current actual wheel speed of the first wheel based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel includes: Based on the vehicle's braking correlation parameters and the current actual wheel speed of each second wheel, determine the current reference wheel speed of the first wheel predicted based on each second wheel; The current actual wheel speed of the first wheel is determined based on the braking correlation parameters and the current reference wheel speeds.

9. A vehicle control device, characterized in that, The device includes: The wheel speed determination module is used to determine the current actual wheel speed of the first wheel based on the braking correlation parameters of the vehicle and the current actual wheel speed of each second wheel when the wheel speed of the first wheel in the vehicle is detected to be missing; wherein, each second wheel is the wheel of the vehicle other than the first wheel. The coefficient determination module is used to determine the current slip ratio of each wheel based on the current actual wheel speed and the current vehicle speed in the braking correlation parameters, and to determine the current adhesion coefficient of the wheel based on the braking correlation parameters and the vertical load of the wheel; and to determine the target adhesion coefficient of the wheel based on the current slip ratio, the current adhesion coefficient and the historical adhesion coefficient. The vehicle control module is used to determine the target motor torque of each wheel based on the braking correlation parameters, the target adhesion coefficient of each wheel and the current actual wheel speed, and control the operation of the corresponding wheel based on the target motor torque of each wheel.

10. A vehicle, characterized in that, The vehicle includes a vehicle controller, as well as braking systems and sensors corresponding to each wheel; wherein the vehicle controller is connected to the braking system and the sensors, and the vehicle controller is used to execute the method according to any one of claims 1-8.

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