Vehicle control methods, vehicle controllers and new energy vehicles

Abstract

This application relates to a vehicle control method, a vehicle controller, and a new energy vehicle, belonging to the field of vehicle control technology. The method includes: when at least one wheel of a target axle is slipping, acquiring a first yaw moment and a second yaw moment of the target axle, wherein the wheels on both sides of the target axle are driven by different motors; the first yaw moment is determined based on the torque requested by the driver, and the second yaw moment is determined based on the anti-slip torque of the slipping wheel of the target axle; determining a target torque for the wheels on both sides of the target axle based on the first yaw moment, the second yaw moment, a real-time yaw moment threshold, and the anti-slip torque; and controlling the operation of the target axle of the vehicle based on the target torque. This method can improve the overall stability of vehicle operation.

Description

Technical Field

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

[0002] Vehicle anti-skid control technology is a core pillar of modern automotive safety. During start-up, rapid acceleration, or on low-traction surfaces (such as ice, snow, gravel, or wet surfaces), the drive wheels may spin and slip due to excessive power. Anti-skid control technology reduces the vehicle's output torque or applies braking to the slipping wheels to suppress slippage, ensuring effective power transmission to the road surface and maintaining vehicle stability and directional controllability. However, when anti-skid control is applied, uneven torque between the left and right wheels on the same axle can easily occur, leading to yaw moments around the vehicle's center of gravity, which is detrimental to lateral stability control.

[0003] Currently, lateral stability control of vehicles is mostly achieved through torque or braking intervention via Vehicle Dynamics Control (VDC) to ensure lateral stability. However, this method cannot simultaneously address both anti-skid control and lateral stability control, which is detrimental to the coordinated lateral and longitudinal control of the vehicle and thus affects the overall stability of the vehicle's control.

[0004] Therefore, how to control vehicles to improve the overall stability of vehicle operation has become an urgent problem to be solved. Summary of the Invention

[0005] Based on this, this application addresses the aforementioned technical problems by providing a vehicle control method, a vehicle controller, and a new energy vehicle to improve the overall stability of vehicle operation.

[0006] In a first aspect, this application provides a vehicle control method, including:

[0007] When at least one wheel on the target axle is slipping, a first yaw moment and a second yaw moment of the target axle are obtained. The wheels on both sides of the target axle are driven by different motors. The first yaw moment is determined based on the torque requested by the driver, and the second yaw moment is determined based on the anti-slip torque of the slipping wheel of the target axle.

[0008] Based on the first yaw moment, the second yaw moment, the real-time yaw moment threshold, and the anti-slip torque, the target torque of the wheels on both sides of the target axle is determined;

[0009] The target axle of the vehicle is controlled based on the target torque.

[0010] In the above implementation process, when at least one wheel on the target axle of the vehicle slips, the first yaw moment of the target axle is determined based on the driver's requested torque before the wheel slips, and the second yaw moment is determined based on the anti-slip torque of the slipping wheel. Then, based on the first yaw moment, the second yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the slipping wheel, the target torques on both sides of the target axle are determined. This ensures that the target torque of the wheels on the target axle is obtained by integrating multiple factors, including the yaw moments before and after wheel slippage, the physical limits that the vehicle can withstand under current road conditions, and the anti-slip torque of the slipping wheel. In other words, the determination of the target torque considers both vehicle anti-slip control and lateral stability. Finally, the movement of the wheels on the target axle is controlled according to the target torque, enabling the target axle to not only perform anti-slip control when wheel slippage occurs but also ensure the lateral stability of the target axle. This achieves coordinated lateral and longitudinal stability control when the adhesion on both sides of the vehicle is inconsistent, thereby improving the overall stability of the vehicle control.

[0011] In an optional embodiment of the first aspect, when a first wheel on one side of the target axle is slipping and a second wheel on the other side is not slipping, determining the target torque for the wheels on both sides of the target axle based on the first yaw moment, the second yaw moment, a real-time yaw moment threshold, and the anti-slip torque includes:

[0012] Determine the yaw moment deviation between the first yaw moment and the second yaw moment;

[0013] Based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the first wheel, the target torque of the second wheel is determined;

[0014] The anti-slip torque of the first wheel is determined as the target torque of the first wheel.

[0015] In the above implementation process, based on the yaw moment deviation between the first and second yaw moments, the yaw moment deviation of the target axle due to anti-slip control can be determined. Then, based on the yaw moment deviation, the first yaw moment, and the real-time yaw moment threshold, the target torque of the second wheel is determined. This ensures that, while meeting physical limits (real-time yaw moment threshold), the torque deviation caused by anti-slip control is compensated as much as possible by the torque output of the non-slipping wheels, ensuring stable vehicle operation. Furthermore, the anti-slip torque of the first wheel is determined as the target torque of the corresponding wheel, thus achieving anti-slip control of the slipping wheel.

[0016] In an optional embodiment of the first aspect, determining the target torque of the second wheel based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the first wheel includes:

[0017] When the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, the gradient value of the vehicle at the current operating moment and the current driver-requested torque of the second wheel are obtained.

[0018] The initial torque of the second wheel is determined based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the first wheel.

[0019] Based on the gradient value and the torque requested by the driver, the initial torque of the second wheel is adjusted to obtain the target torque of the second wheel.

[0020] In the above implementation process, when the absolute value of the determined yaw moment deviation is greater than the real-time yaw moment threshold, the embodiment of this application adjusts the torque of the non-slipping wheel on the target axle according to the gradient value of the vehicle at the current running time and the driver-requested torque of the second wheel at the current running time. In this way, the vibration of the non-slipping wheel can be effectively reduced during the process of switching from the driver-requested torque to the target torque, thereby further improving the stability of vehicle operation.

[0021] In an optional embodiment of the first aspect, when both the first wheel on one side of the target axle and the second wheel on the other side are slipping, the anti-slip torque includes a first anti-slip torque corresponding to the first wheel and a second anti-slip torque corresponding to the second wheel.

[0022] The step of determining the target torque of the wheels on both sides of the target axle based on the first yaw moment, the second yaw moment, the real-time yaw moment threshold, and the anti-slip torque includes:

[0023] Determine the yaw moment deviation between the first yaw moment and the second yaw moment;

[0024] Based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, the first anti-slip torque, and the second anti-slip torque, the first initial torque of the first wheel and the second initial torque of the second wheel are determined.

[0025] Based on the first initial torque and the first anti-slip torque, determine the target torque of the first wheel;

[0026] The target torque of the second wheel is determined based on the second initial torque and the second anti-slip torque.

[0027] In the above implementation process, when both wheels on both sides of the target axle slip, a first initial torque of the first wheel is determined based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the second anti-slip torque; and a second initial torque of the second wheel is determined based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the first anti-slip torque. This overcomes the yaw moment deviation caused by the anti-slip control of the target axle by mutual compensation between the wheels on both sides of the target axle. Furthermore, in this embodiment, the torque with the smaller absolute value between the initial torque and the anti-slip torque of the corresponding wheel is determined as the target torque of the corresponding wheel. This helps to reduce the situation where only the lateral stability control of the vehicle is considered while neglecting anti-slip control, ensuring a balance between lateral stability and anti-slip control, and thus improving the overall stability of the vehicle.

[0028] In an alternative embodiment of the first aspect, determining the target torque of the first wheel based on the first initial torque and the first anti-slip torque includes:

[0029] When the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, the gradient value of the vehicle at the current operating moment is obtained;

[0030] Based on the first initial torque and the first anti-slip torque, determine the reserve torque of the first wheel;

[0031] Based on the gradient value and the first anti-slip torque, the reserve torque of the first wheel is adjusted to obtain the target torque of the first wheel.

[0032] In the above implementation process, when both wheels on both sides of the target axle slip, the reserve torque of the corresponding wheel is adjusted by gradient based on the gradient value of the vehicle at the current running time and the anti-slip torque of the wheel. This effectively reduces vibration during the process of the corresponding wheel switching from anti-slip torque to target torque, thereby improving the overall stability of the vehicle operation.

[0033] In an optional embodiment of the first aspect, determining the reserve torque of the first wheel based on the first initial torque and the first anti-slip torque includes:

[0034] If the first anti-slip torque is greater than the preset value, then the minimum value between the first anti-slip torque and the first initial torque is selected, and the maximum value between the minimum value and the preset value is determined as the spare torque of the first wheel;

[0035] If the first anti-slip torque is less than the preset value, then the maximum value between the first anti-slip torque and the first initial torque is selected, and the minimum value between the maximum value and the preset value is determined as the spare torque for the first wheel.

[0036] In the above implementation process, the type of anti-slip control for the corresponding wheel is determined based on the magnitude of the anti-slip torque on either side of the target axle and the preset value. Based on the type of anti-slip control, the spare torque for the corresponding wheel is selected from the initial torque and anti-slip torque of the corresponding wheel. The selected torque takes into account both wheel anti-slip control and lateral stability, so that when both wheels on both sides of the target axle slip, the wheel can run with a torque that takes into account both anti-slip control and lateral stability, thereby improving the overall stability of the vehicle.

[0037] In an optional embodiment of the first aspect, obtaining the gradient value of the vehicle's current operating time includes:

[0038] Obtain the gradient function activation flag value of the vehicle at the current operating moment;

[0039] The gradient value of the vehicle's current running time is determined based on the gradient function activation flag value, the gradient value of the vehicle's previous running time, the preset maximum gradient value, the preset minimum gradient value, and the time difference between the previous running time and the current running time.

[0040] In the above implementation process, the gradient value of the vehicle's current running time can be accurately determined by using the gradient function activation flag value of the vehicle's current running time, the gradient value of the vehicle's previous running time, the preset maximum gradient value, the preset minimum gradient value, and the time difference between the previous running time and the current running time. This facilitates further gradient adjustment of the wheel torque based on the determined gradient value, thereby reducing wheel vibration caused by torque switching.

[0041] In an optional embodiment of the first aspect, the method further includes:

[0042] Based on the road surface adhesion coefficient corresponding to the current operating time of the vehicle, the road surface adhesion level of the current operating time of the vehicle is determined;

[0043] The real-time yaw moment threshold is determined based on the road surface adhesion level, the vehicle's lateral acceleration and speed at the current operating moment.

[0044] In the above implementation process, the corresponding road adhesion level is determined based on the road adhesion coefficient at the current operating moment of the vehicle. Furthermore, based on the road adhesion level, the vehicle's current speed, and lateral acceleration, the real-time yaw moment threshold is accurately determined, thus facilitating the determination of the axle's lateral stability limit state based on the real-time yaw moment threshold.

[0045] In a second aspect, this application also provides a vehicle controller, comprising: the vehicle controller including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of the method described in any embodiment of the first aspect.

[0046] Thirdly, this application also provides a vehicle controller for a new energy vehicle as described in the second aspect.

[0047] Regarding the beneficial effects of any of the technical solutions in the second and third aspects mentioned above, refer to the beneficial effects of the corresponding technical solutions in the first aspect; repeated examples will not be listed here. Attached Figure Description

[0048] 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 some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 This is a schematic diagram of the optional distribution of four drive motors in a vehicle according to an embodiment of this application;

[0050] Figure 2 This is a schematic diagram of the optional distribution of three drive motors in a vehicle according to an embodiment of this application;

[0051] Figure 3 This is a schematic diagram of another optional distribution of three drive motors in a vehicle provided in an embodiment of this application;

[0052] Figure 4 This is a schematic flowchart of an optional vehicle control method provided in an embodiment of this application;

[0053] Figure 5 This is a schematic flowchart of an optional method for determining the target torque of the wheels on both sides of an axle, provided in an embodiment of this application.

[0054] Figure 6 This is a schematic diagram of an optional vehicle controller provided in an embodiment of this application. Detailed Implementation

[0055] 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 for illustrative purposes only and are not intended to limit the scope of this application.

[0056] The terms "first," "second," etc., used in this application may be used to describe various elements, but these elements are not limited by these terms. These terms are used only to distinguish the first element from the second element. The terms "comprising" and "having," and any variations thereof, used in this application, are intended to cover non-exclusive inclusion. The term "multiple" used in this application refers to two or more. The term "and / or" used in this application refers to one of the embodiments, or any combination of multiple embodiments.

[0057] Vehicle anti-skid control technology reduces vehicle output torque or applies braking to slipping wheels to suppress slippage, ensuring effective power transmission to the road surface and maintaining vehicle stability and directional controllability. However, when a vehicle is traveling on a surface with inconsistent adhesion, situations such as one wheel activating anti-skid control to reduce torque on one axle but not the other, or both wheels activating anti-skid control but with inconsistent torque reduction, can cause yaw moments around the vehicle's center of gravity, which is detrimental to vehicle stability.

[0058] Current methods for controlling vehicle lateral stability cannot simultaneously address both anti-skid control and lateral stability control, which is detrimental to the overall stability of the vehicle.

[0059] Therefore, how to improve the stability of vehicle control by controlling vehicle operation has become an urgent problem to be solved.

[0060] The vehicle control method provided in this application embodiment can be applied to, for example... Figure 1 , Figure 2 as well as Figure 3 In the chassis domain controller of the vehicle shown. Figure 1 , Figure 2 as well as Figure 3 Taking four wheels as an example, Figure 1 , Figure 2 as well as Figure 3 Using the longitudinal centerline as the boundary, the two wheels on the left are designated as the two front wheels on the same axle of the vehicle, and the two wheels on the right are designated as the two rear wheels on the same axle of the vehicle.

[0061] Figure 1 This is a schematic diagram illustrating the optional distribution of four drive motors in a vehicle, as provided in an embodiment of this application. Figure 1 The vehicle shown includes four drive motors. Figure 1Two drive motors are installed on each of the left and right sides of the chassis. Each drive motor is connected to a corresponding wheel on the same side, transmitting torque to that wheel and controlling its movement. A wheel speed sensor is located next to each wheel to detect its speed. All drive motors and wheel speed sensors are connected to the vehicle's chassis domain controller via a Controller Area Network (CAN) cable. This allows the chassis domain controller to accurately obtain the torque and corresponding wheel speed of each wheel, thereby controlling its movement.

[0062] Figure 2 This is a schematic diagram illustrating the optional distribution of three drive motors in a vehicle, as provided in an embodiment of this application. Figure 2 The vehicle shown includes three drive motors. Figure 2 One drive motor is installed on the left side, and two drive motors are installed on the right side. Figure 2 The two front wheels on the left are connected to a drive motor on the left, which transmits torque to the two front wheels. The two rear wheels on the right are each connected to a corresponding drive motor on the same side. Each drive motor on the right transmits torque to its corresponding rear wheel, allowing the drive motor to control the movement of the corresponding wheel. A wheel speed sensor is installed next to each wheel to detect its speed. All drive motors and wheel speed sensors are connected to the vehicle's chassis domain controller via a CAN bus. This allows the chassis domain controller to accurately obtain the torque and corresponding wheel speed of each wheel in the vehicle, thereby controlling the movement of each wheel.

[0063] Figure 3 This is a schematic diagram illustrating another optional distribution of three drive motors in a vehicle, as provided in an embodiment of this application. Figure 3 The vehicle shown includes three drive motors. Figure 3 Two drive motors are installed on the left side, and one drive motor is installed on the right side. Figure 3 The two front wheels on the left are each connected to a corresponding drive motor on the same side. Each drive motor on the left transmits torque to its corresponding front wheel. The two rear wheels on the right are connected to a drive motor on the right, which transmits torque to the two rear wheels on the right, thus controlling the movement of the corresponding wheels. A wheel speed sensor is installed next to each wheel to detect its speed. All drive motors and wheel speed sensors are connected to the vehicle's chassis domain controller via a CAN bus, enabling the chassis domain controller to accurately obtain the torque and corresponding wheel speed of each wheel in the vehicle.

[0064] exist Figure 1 , Figure 2 as well as Figure 3 In the schematic diagram of drive motor distribution shown, if two wheels on the same shaft are each connected to a corresponding drive motor, the two drive motors on the same shaft can output different torques, thus causing the two wheels on the same shaft to run with different torques; if two wheels on the same shaft are connected to a drive motor, the torque output by the drive motor is applied to both wheels, then the two wheels on the same shaft run with the same torque.

[0065] It is understood that the embodiments of this application are only illustrated with the example of one wheel on each side of an axle. In actual scenarios, the vehicle control method of the embodiments of this application is also applicable to vehicles with two wheels on each side of an axle, or vehicles with three wheels on each side of an axle, such as large trucks, and is not limited here.

[0066] In one exemplary embodiment, Figure 4 This is a flowchart illustrating an optional vehicle control method provided in an embodiment of this application. This embodiment applies this method to... Figure 1 , Figure 2 or Figure 3 Taking the chassis domain controller as an example, it's understandable that this method can also be applied to the vehicle domain controller. The vehicle domain controller interacts with the chassis domain controller to control the vehicle; no limitations are imposed here. Figure 4 As shown, this includes the following steps:

[0067] Step 401: When at least one wheel of the target axle is slipping, obtain the first yaw moment and the second yaw moment of the target axle.

[0068] The wheels on both sides of the target axle are driven by different motors. The first yaw moment is determined based on the torque requested by the driver, and the second yaw moment is determined based on the anti-slip torque of the wheel on the target axle that is slipping.

[0069] For example, in order for the chassis domain controller to control the torque of the wheels on both sides of the same axle separately, the axle whose wheels on both sides of the same axle are driven by different drive motors can be identified as the target axle. For example, it can be... Figure 1 If either the left or right axle is designated as the target axle, then... Figure 2 The axle on the right side of the middle section is identified as the target axle, and can be... Figure 3 The axle on the left side of the vehicle is identified as the target axle.

[0070] When a vehicle is driving on surfaces with inconsistent adhesion, such as low-adhesion surfaces, split surfaces, or checkerboard surfaces, the wheels on both sides of the target axle may slip. In this case, the vehicle's anti-slip control function will reduce the torque of the wheels. That is, the chassis domain controller controls the drive motor to output anti-slip torque to the slipping wheels. If the torque output by the wheels on both sides of the same axle is inconsistent, it will cause the vehicle to generate a yaw moment around its center of gravity, which is not conducive to the vehicle's driving stability.

[0071] To improve vehicle stability, it is necessary to minimize the torque deviation between the wheels on both sides of the same axle. However, functions such as U-turns, U-turns on the spot, and drift control mainly rely on the torque difference between the wheels on both sides of the same axle. To reduce functional conflicts, the vehicle control method in this application embodiment can be implemented when the functions that rely on the torque difference between the wheels on both sides of the same axle are not activated, i.e., when the functions such as U-turns, U-turns on the spot, and drift control are not activated.

[0072] Therefore, in order to determine the impact of the vehicle's anti-skid control function on vehicle stability, when at least one of the wheels on both sides of the target axle is slipping, and the compass turn, stationary turn, and drift control functions are not activated, the chassis domain controller can determine the first yaw moment of the target axle based on the driver's requested torque on the wheels on both sides of the target axle, and determine the second yaw moment of the target axle based on the anti-skid torque of the slipping wheel based on the vehicle's anti-skid control function.

[0073] Specifically, the chassis domain controller can determine the first yaw moment based on the driver's requested torque, the turning angle of the wheels on both sides of the target axle, the wheel track between the wheels on both sides, and the radius of the wheels on both sides.

[0074] As an example, the first yaw moment can be determined by the following expression (1):

[0075] (1);

[0076] In equation (1), The first yaw moment of the target axle, in units of ; These are the torque requests from the drivers for the left and right wheels of the target axle, respectively, in units of... ; These are the radii of the left and right wheels of the target vehicle axle, respectively, in meters. These are the rotation angles of the left and right wheels of the target vehicle axle, respectively, in rad; The distance between the wheels on the left and right sides of the target axle is measured in meters (m).

[0077] If the vehicle applies anti-slip control to the target axle, the chassis domain controller will calculate the anti-slip torque required for the slipping wheel in the target axle. Then, the chassis domain controller can determine the second yaw moment of the target axle based on the anti-slip torque of the slipping wheel in the target axle, the turning angle of the wheels on both sides of the target axle, the wheel track between the two sides, and the radius of the two sides of the wheels.

[0078] As an example, the second yaw moment can be determined by the following expression (2):

[0079] (2);

[0080] In equation (2), The second yaw moment of the target axle, in units of If the left wheel of the target axle slips, This refers to the anti-slip torque of the left wheel of the target axle; if the left wheel of the target axle does not slip, but the right wheel slips, Request torque for the driver of the left wheel of the target axle; if the right wheel of the target axle slips, This refers to the anti-slip torque of the right wheel of the target axle; if the right wheel of the target axle does not slip, but the left wheel slips, The driver requests torque for the right wheel of the target axle.

[0081] As an example, the anti-slip torque of the slipping wheel in the target axle can be determined in the following way:

[0082] Calculate the target wheel speed of the slipping wheel based on the speed of motion of the wheel axle (i.e., the center point where the wheel connects to the suspension) relative to the ground and the target slip ratio:

[0083] (3);

[0084] In equation (3), To slip the wheels Target wheel speed, This represents a slipping wheel, taking a four-wheel drive vehicle as an example. Represents the left front wheel. Represents the right front wheel. Represents the left rear wheel. Represents the right rear wheel; To slip the wheels The speed of the wheel axle relative to the ground; To slip the wheels Target slip ratio, target slip ratio It can be obtained by multiplying the vehicle speed sub-target slip ratio by the correction factor, i.e. ,in, The vehicle speed is the sub-target slip ratio; This is a correction factor.

[0085] As an example, the vehicle speed sub-target slip ratio can be obtained by looking up the vehicle speed in the first preset mapping relationship lookup table, and the correction coefficient can be obtained by looking up the road surface adhesion coefficient in the second preset mapping relationship lookup table.

[0086] The first preset mapping relationship comparison table and the second preset mapping relationship comparison table can be obtained by those skilled in the art through calibration in actual scenarios.

[0087] Specifically, the calibration method for the first preset mapping relationship table can be as follows: The test vehicle can be placed on a uniform low-friction road surface. A uniform low-friction road surface refers to a surface where the coefficient of friction (grip) is uniform and consistent throughout the entire test section, without sudden changes, and the friction between the tires and the ground is very small, making the road surface very slippery. When the vehicle speed is less than 18 kph, the vehicle speed sub-target slip ratio at different vehicle speeds is calibrated. When a certain amount of wheel slip is allowed, and the wheel speed reaches the vehicle speed sub-target slip ratio, the wheel contacts the ground smoothly without obvious vibration. When the vehicle speed is higher than 18 kph, the vehicle speed sub-target slip ratio at different vehicle speeds is calibrated so that when the actual wheel speed is controlled according to the vehicle speed sub-target slip ratio, the optimal vehicle dynamics are achieved. As an example, Table 1 is the first preset mapping relationship table, which includes the vehicle speed sub-target slip ratio corresponding to different vehicle speeds. Table 1 example is as follows:

[0088] Table 1

[0089]

[0090] The calibration method for the second preset mapping relationship lookup table can be as follows: After completing the calibration of Table 1, the test vehicle is placed on different uniform low-adhesion road surfaces; by calibrating the correction coefficient based on the road surface adhesion coefficient, the effect of the calibration process in Table 1 under different road surface adhesion coefficients is achieved, thereby realizing the calibration of the second preset mapping relationship lookup table. As an example, Table 2 is the second preset mapping relationship lookup table, which includes correction coefficients corresponding to different road surface adhesion coefficients. An example of Table 2 is shown below:

[0091] Table 2

[0092]

[0093] For values ​​not directly shown in Tables 1 and 2, they can be determined using rules pre-defined by those skilled in the art, such as interpolation, which will not be elaborated here.

[0094] Calculate the wheel speed deviation based on the actual wheel speed of the slipping wheel and the target wheel speed:

[0095] (4);

[0096] In equation (4), To slip the wheels Wheel speed deviation; To slip the wheels Target wheel speed; Slipping wheel measured by wheel speed sensor The actual wheel speed.

[0097] Calculate the adhesion coefficient utilization rate of the slipping wheel based on the driving force and vertical load of the slipping wheel:

[0098] (5);

[0099] In equation (5), To slip the wheels The utilization rate of the adhesion coefficient; To slip the wheels The driving force; To slip the wheels Vertical load.

[0100] The driving force of the slipping wheel can be calculated based on the actual torque, angular acceleration, and wheel radius at the wheel end, i.e.:

[0101] (6);

[0102] In equation (6), To slip the wheels The driving force; To slip the wheels The actual torque at the wheel end; To slip the wheels The moment of inertia at the wheel end; To slip the wheels angular acceleration; The radius is the wheel radius.

[0103] The feedforward control torque is calculated based on the actual torque at the wheel end of the slipping wheel, the moment of inertia at the wheel end, and the angular acceleration.

[0104] (7);

[0105] In equation (7), To slip the wheels The feedforward control torque, which is the wheel-end torque of the maximum available longitudinal ground force, is used to control wheel slippage. The feedforward control torque is the slipping wheel. The torque is the torque remaining after subtracting the torque from the corresponding moment of inertia from the actual torque at the wheel end. In actual control, it is desirable to use the actual torque at the wheel end at the moment of anti-slip activation as the feedforward torque, and then superimpose it with the feedback control torque for control.

[0106] The deviation between the actual torque at the wheel end of the slipping wheel and the feedforward control torque is used as the basis torque for feedback control.

[0107] (8);

[0108] In equation (8), The base torque for feedback control; To slip the wheels The actual torque at the wheel end; To slip the wheels Feedforward control torque.

[0109] The torque adjustment is calculated using a PID controller based on the wheel speed deviation, and then added to the base torque of the feedback control to obtain the final feedback control torque, i.e.:

[0110] (9);

[0111] In equation (9), To slip the wheels Feedback control torque; The scaling factor can be determined based on the first scaling factor. Second proportional coefficient and the third proportional coefficient Multiply to get For the physical model coefficient P, the value is 1, and the unit is Nm / (km / h); The integral coefficients can be determined based on the first integrand coefficients. Second Integral Coefficients and the coefficients of the third integrator Multiplying them together, we get For the I-term of the physical model coefficients, the value is 1, and N is... m / (km / h·s); The differential coefficients can be determined based on the first molecule coefficient. Second molecular coefficient and the third molecular coefficient Multiplying them together, we get This is the coefficient of the physical model in item D, with a value of 1 and a unit of Nm·s / (km / h).

[0112] As an example, the first proportional coefficient Second proportional coefficient Third proportional coefficient First Integral Coefficients Second Integral Coefficients Third Integral Coefficients First molecular coefficient Second molecular coefficient and the third molecular coefficient The values ​​can be obtained by looking up the third, fourth, and fifth preset mapping relationship tables based on the vehicle speed, road surface adhesion coefficient, and wheel speed deviation, respectively.

[0113] The third, fourth, and fifth preset mapping relationship comparison tables can be calibrated by those skilled in the art in actual scenarios.

[0114] Specifically, the calibration method for the third preset mapping relationship lookup table can be as follows: place the test vehicle on a uniform low-friction road surface and calibrate at different vehicle speeds. , as well as This allows the slipping wheel speed to quickly follow the target slip ratio, thus obtaining the third preset mapping relationship lookup table. As an example, Table 3 is the third preset mapping relationship lookup table, which includes the first proportional coefficient corresponding to different vehicle speeds. First Integral Coefficients and the first molecular coefficient Table 3 is an example as follows:

[0115] Table 3

[0116]

[0117] The calibration method for the fourth preset mapping relationship comparison table can be as follows: place the test vehicle on different uniform low-adhesion road surfaces and calibrate... , as well as This allows the slipping wheel speed to quickly follow the target slip ratio, thus obtaining the fourth preset mapping relationship lookup table. As an example, Table 4 is the fourth preset mapping relationship lookup table, which includes the second proportional sub-coefficient corresponding to different road surface adhesion coefficients. Second Integral Coefficients Second molecular coefficient Table 4 is an example as follows:

[0118] Table 4

[0119]

[0120] The calibration method for the fifth preset mapping relationship lookup table can be: test the slippage of the driving wheels of the vehicle, and calibrate the deviation difference under different wheel speeds. , as well as This allows the slipping wheel speed to quickly follow the target slip ratio, thus obtaining the fifth preset mapping relationship lookup table. As an example, Table 5 is the fifth preset mapping relationship lookup table, which includes the third proportional coefficient corresponding to different wheel speed deviations. Third Integral Coefficients and the third molecular coefficient Table 5 is an example as follows:

[0121] Table 5

[0122]

[0123] The final output anti-slip torque for slipping wheels for:

[0124] (10)

[0125] Step 402: Based on the first yaw moment, the second yaw moment, the real-time yaw moment threshold, and the anti-slip torque, determine the target torque of the wheels on both sides of the target axle.

[0126] For example, during vehicle operation, the greater the yaw moment of the axle, the less stable the vehicle is laterally; conversely, the smaller the yaw moment of the axle, the more stable the vehicle is laterally. Theoretically, the vehicle is most stable laterally when the axle yaw moment is zero. Therefore, the lateral stability of a vehicle can be limited by setting a yaw moment threshold.

[0127] Factors influencing the yaw moment threshold typically include the road surface adhesion coefficient, vehicle speed, and lateral acceleration. Since vehicles are more prone to instability on low-adhesion surfaces, at high speeds, and during cornering, the general approach to setting the yaw moment threshold is as follows: the lower the road surface adhesion coefficient, the higher the vehicle speed, and the greater the lateral acceleration, the smaller the yaw moment threshold should be; conversely, the higher the road surface adhesion coefficient, the lower the vehicle speed, and the smaller the lateral acceleration, the larger the yaw moment threshold should be. Therefore, the corresponding yaw moment threshold can be set in real-time based on the road surface adhesion coefficient, vehicle speed, and lateral acceleration during vehicle operation, thus obtaining the real-time yaw moment threshold.

[0128] Then, based on the first yaw moment of the target axle before anti-skid control, the second yaw moment of the target axle after anti-skid control, and the real-time yaw moment threshold, and combined with the anti-skid torque of the slipping wheel, the target torque of the wheels on both sides of the target axle is determined. Thus, the target torque of the wheels on the target axle is obtained by combining multiple factors such as the yaw moment of the wheels on the target axle before and after slippage, the physical limits that the vehicle can withstand under the current road conditions, and the anti-skid torque of the slipping wheel. In this way, the target torque can ensure the lateral stability of the vehicle while ensuring anti-skid control.

[0129] Step 403: Control the target axle of the vehicle to operate based on the target torque.

[0130] Then the chassis domain controller transmits the determined target torque to the drive motor corresponding to the wheel, so that the drive motor transmits the corresponding target torque to the corresponding wheel on the target axle, thereby enabling the chassis domain controller to control the operation of the corresponding wheel on the target axle through the drive motor.

[0131] If there are slipping wheels on each axle of the vehicle, the target torque of each wheel on each axle is determined according to the method of steps 401-403 above. Then, the chassis domain controller controls the operation of all wheels in the vehicle according to the target torque of all wheels to improve the stability of the overall vehicle control.

[0132] In the above implementation process, when at least one wheel on the target axle of the vehicle slips, the first yaw moment of the target axle is determined based on the driver's requested torque before the wheel slips, and the second yaw moment is determined based on the anti-slip torque of the slipping wheel. Then, based on the first yaw moment, the second yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the slipping wheel, the target torques on both sides of the target axle are determined. This ensures that the target torque of the wheels on the target axle is obtained by integrating multiple factors, including the yaw moments before and after wheel slippage, the physical limits that the vehicle can withstand under current road conditions, and the anti-slip torque of the slipping wheel. In other words, the determination of the target torque considers both vehicle anti-slip control and lateral stability. Finally, the movement of the wheels on the target axle is controlled according to the target torque, enabling the target axle to not only perform anti-slip control when wheel slippage occurs but also ensure the lateral stability of the target axle. This achieves coordinated lateral and longitudinal stability control when the adhesion on both sides of the vehicle is inconsistent, thereby improving the overall stability of the vehicle control.

[0133] In one possible embodiment, after determining the first yaw moment, the second yaw moment, and the real-time yaw moment threshold, the yaw moment deviation of the target axle can be obtained based on the difference between the first yaw moment and the second yaw moment. Then, based on the magnitude between the yaw moment deviation and the real-time yaw moment threshold, the lateral stability of the target axle is determined. Furthermore, based on the lateral stability of the target axle and the anti-slip torque of the slipping wheel, the target torque of the wheels on both sides of the target axle is determined.

[0134] Specifically, the difference between the first yaw moment and the second yaw moment is defined as the yaw moment deviation. As an example, the yaw moment deviation... It can be: .

[0135] When the absolute value of the yaw moment deviation is less than or equal to the real-time yaw moment threshold, it indicates that the lateral stability of the target axle is within a controllable range when anti-slip control is applied to the slipping wheel on the target axle. In this case, the target torque for the slipping wheel on the target axle is the anti-slip torque for the slipping wheel, and the target torque for the non-slipping wheel on the target axle is the torque requested by the driver. That is, when both wheels on the target axle are slipping, the target torque for the wheels on both sides of the target axle is the corresponding anti-slip torque; when one wheel on the target axle is slipping and the other wheel is not slipping, the target torque for the slipping wheel is the anti-slip torque for the slipping wheel, and the target torque for the non-slipping wheel is the torque requested by the driver.

[0136] When the absolute value of the yaw moment deviation exceeds the real-time yaw moment threshold, it indicates that applying anti-slip control to the slipping wheel on the target axle will cause lateral instability of the target axle. Therefore, the driver-requested torque of the non-slipping wheel on the target axle can be adjusted, or the anti-slip torque of the slipping wheel on the target axle can be adjusted, so that the deviation between the adjusted yaw moment and the first yaw moment is less than or equal to the real-time yaw moment threshold. The target torque for the slipping wheel on the target axle is either the anti-slip torque of the slipping wheel or the adjusted anti-slip torque of the slipping wheel, while the target torque for the non-slipping wheel on the target axle is the adjusted driver-requested torque.

[0137] As an example, when the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, and one wheel on the target axle is slipping while the other is not, the driver-requested torque of the non-slipping wheel on the target axle is adjusted step-by-step using a preset gradient to obtain the adjusted driver-requested torque. Each time the driver-requested torque of the non-slipping wheel is adjusted, the adjusted yaw moment of the target axle is calculated based on the adjusted driver-requested torque, and the deviation between the adjusted target axle yaw moment and the first yaw moment is determined. This step of adjusting the driver-requested torque of the non-slipping wheel on the target axle step-by-step using a preset gradient is repeated until the deviation between the adjusted target axle yaw moment and the first yaw moment is less than or equal to the real-time yaw moment threshold. When the deviation between the adjusted target axle yaw moment and the first yaw moment is less than or equal to the real-time yaw moment threshold, the corresponding adjusted driver-requested torque is determined as the target torque for the non-slipping wheel, and the anti-slip torque of the slipping wheel is determined as the target torque for the slipping wheel.

[0138] As another example, when the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, and both wheels on the target axle are slipping, the anti-slip torque of the slipping wheels on both sides of the target axle is adjusted alternately in a preset gradient to obtain the adjusted anti-slip torque for each slipping wheel. Each time the anti-slip torque of the slipping wheel is adjusted, the adjusted yaw moment of the target axle is calculated based on the adjusted anti-slip torque, and the deviation between the adjusted yaw moment and the first yaw moment is determined. This process of alternately adjusting the anti-slip torque of the slipping wheels on both sides of the target axle in a preset gradient is repeated until the deviation between the adjusted yaw moment and the first yaw moment is less than or equal to the real-time yaw moment threshold. When the deviation between the adjusted yaw moment and the first yaw moment is less than or equal to the real-time yaw moment threshold, the adjusted anti-slip torque of each slipping wheel is determined as the target torque for that corresponding slipping wheel.

[0139] It is understandable that the preset gradient can be a small value set according to the actual scenario, such as 0.1, 0.2 or 0.3, or other gradient values, without any restrictions.

[0140] In the above implementation process, when at least one wheel on the target axle of the vehicle slips, the first yaw moment of the target axle is determined based on the driver's requested torque before the wheel slips, and the second yaw moment is determined based on the anti-slip torque of the slipping wheel. Then, the yaw moment deviation is determined based on the first and second yaw moments, and the lateral stability of the target axle is determined based on the magnitude between the yaw moment deviation and the real-time yaw moment threshold. Combined with the anti-slip torque of the slipping wheel, the target torques on both sides of the target axle are determined. Finally, the wheel movement on the target axle is controlled according to the target torque, so that the target axle can not only perform anti-slip control when the wheel slips, but also ensure the lateral stability of the target axle during anti-slip control. This achieves lateral and longitudinal coordinated stability control when the adhesion on both sides of the vehicle is inconsistent, thereby improving the stability of the overall vehicle control.

[0141] In one embodiment, when the first wheel on one side of the target axle is slipping and the second wheel on the other side is not slipping, the target torque of the wheels on both sides of the target axle is determined based on the first yaw moment, the second yaw moment, the real-time yaw moment threshold, and the anti-slip torque, which may include the following steps:

[0142] Determine the yaw moment deviation between the first yaw moment and the second yaw moment; based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the first wheel, determine the target torque of the second wheel; and set the anti-slip torque of the first wheel as the target torque of the first wheel.

[0143] For example, the difference between the first yaw moment and the second yaw moment can be determined as the yaw moment deviation. When the absolute value of the yaw moment deviation exceeds the real-time yaw moment threshold, the torque required to maintain lateral stability of the wheels on both sides of the target axle can be determined based on the yaw moment deviation, the first yaw moment, and the real-time yaw moment threshold. Then, the torque required to maintain lateral stability of the wheels on both sides of the target axle is subtracted from the anti-slip torque of the first wheel to obtain the remaining torque. This remaining torque is then distributed to the second wheel according to the steering angle of the second wheel to obtain the target torque for the second wheel.

[0144] In the direction of vehicle travel, if the right front wheel of the target axle slips but the left front wheel does not, then the first wheel of the target axle is the right front wheel, and the second wheel of the target axle is the left front wheel. Then, based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the right front wheel, the target torque of the left front wheel is determined.

[0145] As an example, the target torque of the left front wheel of the target axle can be determined by the following expression (11):

[0146] (11);

[0147] In equation (11), The target torque for the left front wheel of the target axle, in units of ; The anti-slip torque of the target axle's right front wheel, in units ; This is the real-time yaw moment threshold. These are the wheel radii of the left and right front wheels of the target vehicle, respectively, in meters (m). The wheel angle of the left front wheel of the target axle.

[0148] Then, the anti-slip torque when the right front wheel of the target axle slips is determined as the target torque of the right front wheel of the target axle. In this way, the target torque of the wheels on both sides of the target axle can be accurately determined.

[0149] Correspondingly, in the vehicle's forward direction, if the left front wheel of the target axle slips but the right front wheel does not, then the first wheel of the target axle is the left front wheel, and the second wheel of the target axle is the right front wheel. Then, based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the left front wheel, the target torque of the right front wheel is determined.

[0150] As an example, the target torque of the right front wheel of the target axle can be determined by the following expression (12):

[0151] (12);

[0152] In equation (12), The target torque for the right front wheel of the target axle, in units of ; The anti-slip torque of the target axle's left front wheel, in units ; The wheel angle of the right front wheel of the target axle.

[0153] Then, the anti-slip torque when the left front wheel of the target axle slips is determined as the target torque of the left front wheel of the target axle. In this way, the target torque of the wheels on both sides of the target axle can be accurately determined.

[0154] In the above implementation process, based on the yaw moment deviation between the first and second yaw moments, the yaw moment deviation of the target axle due to anti-slip control can be determined. Then, based on the yaw moment deviation, the first yaw moment, and the real-time yaw moment threshold, the target torque of the second wheel is determined. This ensures that, while meeting physical limits (real-time yaw moment threshold), the torque deviation caused by anti-slip control is compensated as much as possible by the torque output of the non-slipping wheels, ensuring stable vehicle operation. Furthermore, the anti-slip torque of the first wheel is determined as the target torque of the corresponding wheel, thus achieving anti-slip control of the slipping wheel.

[0155] In one possible embodiment, determining the target torque of the second wheel based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the first wheel may include the following steps:

[0156] When the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, the gradient value of the vehicle at the current running time and the current driver-requested torque of the second wheel are obtained; based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold and the anti-slip torque of the first wheel, the initial torque of the second wheel is determined; based on the gradient value and the driver-requested torque, the initial torque of the second wheel is adjusted to obtain the target torque of the second wheel.

[0157] For example, in the process of determining the target torque of the second wheel, in order to reduce the vibration of the second wheel caused by the change in torque, the torque of the second wheel can be adjusted in a gradient according to the driver's requested torque and gradient value, so that the second wheel can operate stably with the adjusted target torque.

[0158] Specifically, to ensure that the gradient value matches the timing of gradient adjustment, a corresponding gradient value can be set based on the vehicle's current operating time. As an example, the gradient value for the current operating time can be determined based on the gradient function activation flag value at the current operating time, the gradient value at the vehicle's previous operating time, the preset maximum gradient value, the preset minimum gradient value, and the time difference between the previous and current operating times.

[0159] Then, when the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, the chassis domain controller can obtain the gradient value of the vehicle at the current operating moment and the current driver-requested torque of the second wheel.

[0160] In the direction of vehicle travel, if the right front wheel of the target axle slips but the left front wheel does not, then the first wheel of the target axle is the right front wheel, and the second wheel of the target axle is the left front wheel. Then, based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the right front wheel, the initial torque of the left front wheel is determined.

[0161] As an example, the initial torque of the left front wheel of the target axle can be determined by expression (11). .

[0162] Then, based on the gradient value at the current running time... In addition to the torque requested by the driver, the initial torque of the left front wheel of the target axle is adjusted to obtain the target torque of the left front wheel of the target axle. As an example, the target torque of the left front wheel of the target axle can be determined by the following expression (13). :

[0163] (13);

[0164] In equation (13), The target torque for the left front wheel of the target axle; This represents the gradient value at the current running time t. The driver requests the torque for the left front wheel of the target axle at the current running time t.

[0165] Furthermore, the anti-slip torque of the right front wheel of the target axle is determined as the target torque of the right front wheel.

[0166] Correspondingly, in the vehicle's forward direction, if the left front wheel of the target axle slips but the right front wheel does not, then the first wheel of the target axle is the left front wheel, and the second wheel of the target axle is the right front wheel. Then, based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the anti-slip torque of the left front wheel, the initial torque of the right front wheel is determined.

[0167] As an example, the initial torque of the right front wheel of the target axle can be determined by expression (12). .

[0168] Then based on the obtained gradient values In addition to the torque requested by the driver, the initial torque of the right front wheel of the target axle is adjusted to obtain the target torque of the right front wheel of the target axle. As an example, the target torque of the right front wheel of the target axle can be determined by the following expression (14). :

[0169] (14);

[0170] In equation (14), The target torque for the right front wheel of the target axle; This represents the gradient value at the current running time t. The driver requests the torque for the right front wheel of the target axle at the current running time t.

[0171] Furthermore, the anti-slip torque of the left front wheel of the target axle is determined as the target torque of the left front wheel.

[0172] In the above implementation process, when the absolute value of the determined yaw moment deviation is greater than the real-time yaw moment threshold, the embodiment of this application adjusts the torque of the non-slipping wheel on the target axle according to the gradient value of the vehicle at the current running time and the driver-requested torque of the second wheel at the current running time. In this way, the vibration of the non-slipping wheel can be effectively reduced during the process of switching from the driver-requested torque to the target torque, thereby further improving the stability of vehicle operation.

[0173] In one embodiment, when both the first wheel on one side of the target axle and the second wheel on the other side are slipping, the anti-slip torque includes a first anti-slip torque corresponding to the first wheel and a second anti-slip torque corresponding to the second wheel.

[0174] For example, when both wheels on both sides of the target axle slip, the chassis domain controller will perform anti-slip control on both the first wheel and the second wheel, that is, determine the first anti-slip torque of the first wheel and the second anti-slip torque of the second wheel.

[0175] Determining the target torque for the wheels on both sides of the target axle based on the first yaw moment, the second yaw moment, the real-time yaw moment threshold, and the anti-slip torque may include the following steps:

[0176] Determine the yaw moment deviation between the first yaw moment and the second yaw moment; based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, the first anti-slip torque, and the second anti-slip torque, determine the first initial torque of the first wheel and the second initial torque of the second wheel; based on the first initial torque and the first anti-slip torque, determine the target torque of the first wheel; based on the second initial torque and the second anti-slip torque, determine the target torque of the second wheel.

[0177] For example, the difference between the first yaw moment and the second yaw moment is defined as the yaw moment deviation. If the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, the first initial torque of the first wheel and the second initial torque of the second wheel are determined based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, the first anti-slip torque, and the second anti-slip torque.

[0178] Specifically, the first initial torque of the first wheel is determined based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the second anti-slip torque. Similarly, the second initial torque of the second wheel is determined based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the first anti-slip torque.

[0179] As an example, in the direction of vehicle travel, if the first wheel is the left front wheel of the target axle and the second wheel is the right front wheel of the target axle, the first initial torque of the left front wheel of the target axle can be determined according to expression (11). And the second initial torque of the right front wheel of the target axle is determined according to expression (12). .

[0180] Then, the target torque for the first wheel is selected from the first anti-slip torque and the first initial torque. Specifically, the torque corresponding to the smaller absolute value between the first anti-slip torque and the first initial torque can be determined as the target torque for the first wheel. The target torque for the second wheel is then selected from the second anti-slip torque and the second initial torque. Specifically, the torque corresponding to the smaller absolute value between the second anti-slip torque and the second initial torque can be determined as the target torque for the second wheel.

[0181] For each wheel, the torque with the smaller absolute value between the anti-slip torque and the initial torque is determined as the target torque for that wheel, which can effectively reduce the vibration of the corresponding wheel caused by torque changes.

[0182] In the above implementation process, when both wheels on both sides of the target axle slip, a first initial torque of the first wheel is determined based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the second anti-slip torque; and a second initial torque of the second wheel is determined based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the first anti-slip torque. This overcomes the yaw moment deviation caused by the anti-slip control of the target axle by mutual compensation between the wheels on both sides of the target axle. Furthermore, in this embodiment, the torque with the smaller absolute value between the initial torque and the anti-slip torque of the corresponding wheel is determined as the target torque of the corresponding wheel. This helps to reduce the situation where only the lateral stability control of the vehicle is considered while neglecting anti-slip control, ensuring a balance between lateral stability and anti-slip control, and thus improving the overall stability of the vehicle.

[0183] In one possible embodiment, determining the target torque of the first wheel based on the first initial torque and the first anti-slip torque may include the following steps:

[0184] When the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, the gradient value of the vehicle at the current running moment is obtained; based on the first initial torque and the first anti-slip torque, the reserve torque of the first wheel is determined; based on the gradient value and the first anti-slip torque, the reserve torque of the first wheel is adjusted to obtain the target torque of the first wheel.

[0185] For example, when both wheels on both sides of the target axle are slipping and the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, the gradient value of the vehicle at the current running moment is obtained.

[0186] When the first anti-slip torque is greater than zero, the minimum value between the first anti-slip torque and the first initial torque can be determined as the first reserve torque of the first wheel; when the first anti-slip torque is less than zero, the maximum value between the first anti-slip torque and the first initial torque can be determined as the first reserve torque of the first wheel. Based on the obtained gradient value and the first anti-slip torque, the first reserve torque of the first wheel is adjusted to obtain the target torque of the first wheel.

[0187] As an example, if the first wheel is the left front wheel of the target axle and the second wheel is the right front wheel of the target axle, the first reserve torque is... The target torque of the left front wheel of the target axle can then be determined by the following expression (15):

[0188] (15);

[0189] In equation (15), The target torque for the left front wheel of the target axle; This represents the gradient value at the current running time t. The first reserve torque for the left front wheel of the target axle; The first anti-slip torque for the left front wheel of the target axle.

[0190] Correspondingly, when the second anti-slip torque is greater than zero, the minimum value between the second anti-slip torque and the second initial torque can be determined as the second reserve torque of the second wheel; when the second anti-slip torque is less than zero, the maximum value between the second anti-slip torque and the second initial torque can be determined as the second reserve torque of the second wheel. Based on the obtained gradient value and the second anti-slip torque, the second reserve torque of the second wheel is adjusted to obtain the target torque of the second wheel.

[0191] As an example, if the second reserve torque is The target torque of the right front wheel of the target axle can then be determined by the following expression (16):

[0192] (16);

[0193] In equation (16), The target torque for the right front wheel of the target axle; This represents the gradient value at the current running time t. The second reserve torque for the right front wheel of the target axle; The second anti-slip torque is for the right front wheel of the target axle.

[0194] In the above implementation process, when both wheels on both sides of the target axle slip, the reserve torque of the corresponding wheel is adjusted by gradient based on the gradient value of the vehicle at the current running time and the anti-slip torque of the wheel. This effectively reduces vibration during the process of the corresponding wheel switching from anti-slip torque to target torque, thereby improving the overall stability of the vehicle operation.

[0195] In one possible embodiment, determining the reserve torque of the first wheel based on the first initial torque and the first anti-slip torque may include the following steps:

[0196] If the first anti-slip torque is greater than the preset value, the minimum value between the first anti-slip torque and the first initial torque is selected, and the maximum value between the minimum value and the preset value is determined as the reserve torque of the first wheel; if the first anti-slip torque is less than the preset value, the maximum value between the first anti-slip torque and the first initial torque is selected, and the minimum value between the maximum value and the preset value is determined as the reserve torque of the first wheel.

[0197] For example, when both wheels on both sides of the target axle slip, the type of anti-slip control is determined by the direction of the anti-slip torque of each wheel, and then the reserve torque of the corresponding wheel is determined according to the type of anti-slip control.

[0198] Specifically, the preset value can be 0. By comparing the anti-slip torque with the preset value, the type of anti-slip control for the corresponding wheel can be determined as either drive-type anti-slip or regenerative anti-slip. If the anti-slip torque is greater than the preset value, the type of anti-slip control for the corresponding wheel is drive-type anti-slip; if the anti-slip torque is less than the preset value, the type of anti-slip control for the corresponding wheel is regenerative anti-slip. Then, based on the type of anti-slip control, the spare torque for the corresponding wheel is selected from the anti-slip torque and the initial torque.

[0199] As an example, if the first anti-slip torque is greater than 0, the minimum value between the first anti-slip torque and the first initial torque is selected, and the maximum value between the selected minimum value and 0 is determined as the first reserve torque of the first wheel; if the first anti-slip torque is less than 0, the maximum value between the first anti-slip torque and the first initial torque is selected, and the minimum value between the selected maximum value and 0 is determined as the reserve torque of the first wheel.

[0200] Correspondingly, if the second anti-slip torque is greater than 0, the minimum value between the second anti-slip torque and the second initial torque is selected, and the maximum value between the selected minimum value and 0 is determined as the second reserve torque of the second wheel; if the second anti-slip torque is less than 0, the maximum value between the second anti-slip torque and the second initial torque is selected, and the minimum value between the selected maximum value and 0 is determined as the second reserve torque of the second wheel.

[0201] Specifically, if the first wheel is the left front wheel of the target axle and the second wheel is the right front wheel of the target axle.

[0202] exist In this case, the first reserve torque of the target axle's left front wheel ;exist In this case, the first reserve torque of the target axle's left front wheel .

[0203] Correspondingly, in In this case, the second reserve torque of the right front wheel of the target axle ;exist In this case, the second reserve torque of the right front wheel of the target axle .

[0204] In the above implementation process, the type of anti-slip control for the corresponding wheel is determined based on the magnitude of the anti-slip torque on either side of the target axle and the preset value. Based on the type of anti-slip control, the spare torque for the corresponding wheel is selected from the initial torque and anti-slip torque of the corresponding wheel. The selected torque takes into account both wheel anti-slip control and lateral stability, so that when both wheels on both sides of the target axle slip, the wheel can run with a torque that takes into account both anti-slip control and lateral stability, thereby improving the overall stability of the vehicle.

[0205] In one embodiment, obtaining the gradient value of the vehicle at its current operating moment includes:

[0206] Obtain the gradient function activation flag value at the current running time of the vehicle; based on the gradient function activation flag value, the gradient value at the previous running time of the vehicle, the preset maximum gradient value, the preset minimum gradient value, and the time difference between the previous running time and the current running time, determine the gradient value at the current running time of the vehicle.

[0207] For example, the chassis domain controller can determine whether to activate the torque gradient function based on the magnitude between the absolute value of the yaw moment deviation and the real-time yaw moment threshold, and then obtain the gradient function activation flag value at the current operating moment of the vehicle.

[0208] Specifically, when the absolute value of the yaw moment deviation exceeds the real-time yaw moment threshold, the torque gradient function is activated, and the corresponding gradient function activation flag value is displayed. The value is 1; when the absolute value of the yaw moment deviation is less than or equal to the real-time yaw moment threshold, the torque gradient function is not activated, and the corresponding gradient function activation flag value is 1. It is 0.

[0209] Then, based on the gradient function activation flag value at the current running time, the gradient value at the vehicle's previous running time, the preset maximum gradient value, the preset minimum gradient value, and the time difference between the previous running time and the current running time, the gradient value at the current running time is determined. As an example, the gradient value at the current running time t can be determined using the following expression (17). :

[0210] (17);

[0211] In equation (17), The gradient value is the vehicle's current running time t, and its range is 0~1; This represents the gradient value of the vehicle at the previous running time t-1; This is the gradient function activation flag value for the current vehicle operating moment. Its value is 1 when the torque gradient function is activated and 0 when the torque gradient function is not activated. It represents the time difference between the current running moment and the previous running moment. In practical applications, it can be adaptively set according to the actual scenario. It can also be the interval for data collection by sensors in the vehicle or the running step size of the code, etc. The preset maximum gradient value; To preset the minimum gradient value, it should be understood that to preset the maximum gradient value... Compared with the preset minimum gradient value Adaptive settings can be made based on empirical values ​​from actual applications; no restrictions are imposed here.

[0212] In the above implementation process, the gradient value of the vehicle's current running time can be accurately determined by using the gradient function activation flag value of the vehicle's current running time, the gradient value of the vehicle's previous running time, the preset maximum gradient value, the preset minimum gradient value, and the time difference between the previous running time and the current running time. This facilitates further gradient adjustment of the wheel torque based on the determined gradient value, thereby reducing wheel vibration caused by torque switching.

[0213] In one embodiment, the method may further include the following steps:

[0214] Based on the road surface adhesion coefficient corresponding to the current vehicle operating moment, the road surface adhesion level of the current vehicle operating moment is determined; based on the road surface adhesion level, the lateral acceleration of the vehicle at the current operating moment, and the vehicle speed, the real-time yaw moment threshold is determined.

[0215] For example, in order to accurately determine the yaw moment threshold at the current operating moment, the road adhesion level can be determined based on the road adhesion coefficient corresponding to the current operating moment of the vehicle, and then the real-time yaw moment threshold can be determined based on the road adhesion level, the lateral acceleration of the vehicle at the current operating moment, and the vehicle speed.

[0216] As an example, road surface adhesion coefficients can be classified into three levels based on their magnitude, with a higher coefficient indicating a higher level. Specifically, when the road surface adhesion coefficient is greater than or equal to zero and less than 0.3, the level is Level 1; when it is greater than or equal to 0.3 and less than 0.6, the level is Level 2; and when it is greater than or equal to 0.6 and less than or equal to 1, the level is Level 3.

[0217] Those skilled in the art can calibrate the real-time yaw moment threshold for each road surface adhesion level in a real-world scenario, thereby obtaining a corresponding yaw moment threshold mapping table. Each yaw moment threshold mapping table includes the real-time yaw moment threshold corresponding to different vehicle speeds and different lateral accelerations under the corresponding road surface adhesion level.

[0218] Specifically, the calibration method for the yaw moment threshold under different road surface adhesion levels is as follows: Test measurements are taken on uniform low-adhesion road surfaces, split-type road surfaces, and checkerboard road surfaces with different road surface adhesion coefficients. The road surface adhesion coefficient corresponds to the road surface adhesion level. Tests are conducted at different vehicle speeds. The real-time yaw moment threshold is calibrated by vehicle speed and lateral acceleration, so that the yaw of the test vehicle on uniform low-adhesion road surfaces, split-type road surfaces, and checkerboard road surfaces is controllable or the yaw angular velocity is less than 0.2 rad / s.

[0219] As an example, Table 6 is a yaw moment threshold mapping table corresponding to Level 1 road surface adhesion, Table 7 is a yaw moment threshold mapping table corresponding to Level 2 road surface adhesion, and Table 8 is a yaw moment threshold mapping table corresponding to Level 3 road surface adhesion. As shown in Tables 6, 7, and 8, each road surface adhesion level's yaw moment threshold mapping table includes vehicle speeds at various speeds... Horizontal acceleration at speeds of 0 m / s² at speeds of 20 km / h, 40 km / h, 60 km / h, 80 km / h, and 100 km / h. 2 1m / s 2 2m / s 2 3m / s 2 4m / s 2 5m / s 2 6m / s 2 7m / s 2 8m / s 2 9m / s 2 and 10m / s 2The corresponding real-time yaw moment threshold.

[0220] Table 6

[0221]

[0222] Table 7

[0223]

[0224] Table 8

[0225]

[0226] Based on the current range of the vehicle's road surface adhesion coefficient, the road surface adhesion level of the vehicle at the current operating time can be determined. Then, based on the road surface adhesion level at the current operating time, the corresponding yaw moment threshold mapping table can be found. From the yaw moment threshold mapping table, the real-time yaw moment threshold at the current operating time under the lateral acceleration and vehicle speed can be determined, thereby making the determined real-time yaw moment threshold compatible with the vehicle's current road surface adhesion coefficient, lateral acceleration, and vehicle speed.

[0227] In the above implementation process, the corresponding road adhesion level is determined based on the road adhesion coefficient at the current operating moment of the vehicle. Furthermore, based on the road adhesion level, the vehicle's current speed, and lateral acceleration, the real-time yaw moment threshold is accurately determined, thus facilitating the determination of the axle's lateral stability limit state based on the real-time yaw moment threshold.

[0228] As an example, Figure 5 This is a schematic flowchart of an optional method for determining the target torque of the wheels on both sides of an axle, provided in an embodiment of this application. Figure 5 As shown, the method may include the following steps:

[0229] Step S1: Detect activation conditions.

[0230] Specifically, the activation conditions for implementing the target torque determination method for the wheels on the target axle in this embodiment include two:

[0231] ① All functions in the vehicle that rely on the torque difference between the wheels on both sides of the same axle are not activated.

[0232] For example, the vehicle's U-turn, U-turn on the spot, and drift control functions all rely on the torque difference between the wheels on both sides of the same axle. Therefore, to implement the target torque determination method for the wheels on the target axle in this application embodiment, it is necessary to ensure that all functions such as the vehicle's U-turn, U-turn on the spot, and drift control are not activated.

[0233] ②At least one wheel on at least one axle of the vehicle slips.

[0234] Step S2: Determine the real-time yaw moment threshold.

[0235] Specifically, based on the road surface adhesion coefficient at the current operating moment and the pre-defined road surface adhesion levels, the current road surface adhesion level of the vehicle is determined. Then, from the yaw moment threshold mapping table corresponding to the road surface adhesion level in Tables 6, 7, or 8, the lateral acceleration at the current operating moment and the corresponding real-time yaw moment threshold at the vehicle speed are determined, thus realizing the real-time yaw moment threshold. The determination.

[0236] Step S3: Determine the first yaw moment based on the torque requested by the driver.

[0237] Specifically, if there is a slipping wheel on the target axle of the vehicle, the first yaw moment of the target axle is determined based on the driver's requested torque of the wheel on the target axle. For example, the first yaw moment of the target axle can be determined using the above expression (1). .

[0238] Step S4: Determine the second yaw moment based on the anti-slip torque of the slipping wheel on the target axle.

[0239] Specifically, when a wheel on the target axle slips and the vehicle's anti-slip control function is activated, the slipping wheel will respond to the anti-slip torque first, rather than the torque requested by the driver. At this time, the second yaw moment can be determined based on the anti-slip torque of the slipping wheel. For example, the second yaw moment of the target axle can be determined according to the above expression (2). .

[0240] Step S5: Determine the wheel end torque of the wheel on the target axle.

[0241] If the right front wheel on the target axle slips while the left front wheel does not, the desired torque of the left front wheel on the target axle can be determined according to the above expression (11). If both the right and left front wheels on the target axle slip, the desired torque of the left front wheel can be used as a reference. and the anti-slip torque of the left front wheel Arbitration was conducted to obtain the wheel end torque of the left front wheel after arbitration. Specifically, if ,but ;like ,but .

[0242] Correspondingly, if the left front wheel on the target axle slips while the right front wheel does not, the desired torque of the right front wheel on the target axle can be determined according to the above expression (12). If both the right front wheel and the left front wheel on the target axle slip, the desired torque of the right front wheel can be used as a guide. And the anti-slip torque of the right front wheel Arbitration was conducted to obtain the wheel end torque of the right front wheel after arbitration. Specifically, if ,but ;like ,but .

[0243] Step S6: Perform gradient filtering on the wheel end torque to obtain the target torque of the wheels on both sides of the target axle.

[0244] Specifically, in At that time, the target torque of the wheel slipping on the target axle is the corresponding anti-slip torque, and the target torque of the wheel that is not slipping is the corresponding driver-requested torque.

[0245] exist When the torque gradient is activated, the gradient function activation flag value b changes from 0 to 1, and the wheel-end torque response is the torque after arbitration. The torque will switch from anti-slip torque or driver-requested torque to arbitration torque. If the difference between the two is large, it will cause vibration of the corresponding wheel, affecting the driving experience. Therefore, the switching of the gradient function activation flag value b (including both function activation and deactivation states) needs to be done slowly according to a certain gradient, and the gradient value at the current running moment... The target torque of the wheel can be determined according to expression (17). Then, the wheel end torque is adjusted according to the determined gradient value to obtain the target torque of the wheel.

[0246] Specifically, when the right front wheel of the target axle slips but the left front wheel does not slip, the target torque of the left front wheel of the target axle can be determined by expression (13). At this point, the target torque of the right front wheel of the target axle is the anti-slip torque of the right front wheel.

[0247] If the left front wheel slips on the target axle but the right front wheel does not slip, the target torque of the right front wheel of the target axle can be determined according to expression (14). At this point, the target torque of the left front wheel of the target axle is the anti-slip torque of the left front wheel.

[0248] When both the left and right front wheels on the target axle slip, the target torque of the left front wheel of the target axle can be determined according to expression (15). And determine the target torque of the right front wheel of the target axle according to expression (16). .

[0249] Finally, based on the target torque determined on both sides of the target axle, the movement of the wheels on the target axle can be controlled.

[0250] 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 in other steps. It is understood that the steps in different embodiments can be freely combined as needed, and all non-contradictory solutions formed by such combinations are within the scope of protection of this application.

[0251] 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.

[0252] In one exemplary embodiment, the vehicle control device provided in this application includes:

[0253] The acquisition module is used to acquire a first yaw moment and a second yaw moment of the target axle when at least one wheel of the target axle is slipping. The wheels on both sides of the target axle are driven by different motors. The first yaw moment is determined based on the torque requested by the driver, and the second yaw moment is determined based on the anti-slip torque of the slipping wheel of the target axle.

[0254] The determination module is used to determine the target torque of the wheels on both sides of the target axle based on the first yaw moment, the second yaw moment, the real-time yaw moment threshold, and the anti-slip torque.

[0255] The control module is used to control the operation of the target axle of the vehicle based on the target torque.

[0256] In one exemplary embodiment, a vehicle controller is provided. Figure 6 This is a schematic diagram of an optional vehicle controller provided in an embodiment of this application, such as... Figure 6 As shown, the vehicle controller includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method in any of the above embodiments.

[0257] In one exemplary embodiment, this application also provides a new energy vehicle, including... Figure 6 The vehicle controller shown.

[0258] 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 mentioned can be stored in a non-volatile computer-readable storage medium. When executed, the computer program 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.

[0259] 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.

[0260] 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: When both the first wheel on one side of the target axle and the second wheel on the other side are slipping, the first yaw moment and the second yaw moment of the target axle are obtained. The wheels on both sides of the target axle are driven by different motors. The first yaw moment is determined based on the torque requested by the driver, and the second yaw moment is determined based on the anti-slip torque of the slipping wheel of the target axle. The anti-slip torque includes the first anti-slip torque corresponding to the first wheel and the second anti-slip torque corresponding to the second wheel. Determine the yaw moment deviation between the first yaw moment and the second yaw moment; Based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, the first anti-slip torque, and the second anti-slip torque, the target torques corresponding to the first wheel and the second wheel are determined respectively, specifically including: When the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold; based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, the first anti-slip torque, and the second anti-slip torque, determine the first initial torque of the first wheel and the second initial torque of the second wheel; based on the first initial torque of the first wheel and the second initial torque of the second wheel, determine the target torques corresponding to the first wheel and the second wheel respectively; The target axle of the vehicle is controlled to operate based on the target torques corresponding to the first wheel and the second wheel, respectively.

2. The method according to claim 1, characterized in that, The step of determining the target torques corresponding to the first wheel and the second wheel respectively based on the first initial torque of the first wheel and the second initial torque of the second wheel includes: Based on the first initial torque and the first anti-slip torque, determine the target torque of the first wheel; The target torque of the second wheel is determined based on the second initial torque and the second anti-slip torque.

3. The method according to claim 1, characterized in that, The step of determining the first initial torque of the first wheel and the second initial torque of the second wheel based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, the first anti-slip torque, and the second anti-slip torque includes: Based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the second anti-slip torque, the first initial torque of the first wheel is determined; The second initial torque of the second wheel is determined based on the yaw moment deviation, the first yaw moment, the real-time yaw moment threshold, and the first anti-slip torque.

4. The method according to claim 2, characterized in that, Determining the target torque of the first wheel based on the first initial torque and the first anti-slip torque includes: When the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, the gradient value of the vehicle at the current operating moment is obtained; Based on the first initial torque and the first anti-slip torque, determine the reserve torque of the first wheel; Based on the gradient value and the first anti-slip torque, the reserve torque of the first wheel is adjusted to obtain the target torque of the first wheel.

5. The method according to claim 2, characterized in that, Determining the target torque of the second wheel based on the second initial torque and the second anti-slip torque includes: When the absolute value of the yaw moment deviation is greater than the real-time yaw moment threshold, the gradient value of the vehicle at the current operating moment is obtained; Based on the second initial torque and the second anti-slip torque, determine the reserve torque of the second wheel; Based on the gradient value and the second anti-slip torque, the reserve torque of the second wheel is adjusted to obtain the target torque of the second wheel.

6. The method according to claim 4, characterized in that, Determining the reserve torque of the first wheel based on the first initial torque and the first anti-slip torque includes: If the first anti-slip torque is greater than the preset value, then the minimum value between the first anti-slip torque and the first initial torque is selected, and the maximum value between the minimum value and the preset value is determined as the spare torque of the first wheel; If the first anti-slip torque is less than the preset value, then the maximum value between the first anti-slip torque and the first initial torque is selected, and the minimum value between the maximum value and the preset value is determined as the spare torque for the first wheel.

7. The method according to claim 4 or 5, characterized in that, The step of obtaining the gradient value of the vehicle at its current operating moment includes: Obtain the gradient function activation flag value of the vehicle at the current operating moment; The gradient value of the vehicle's current running time is determined based on the gradient function activation flag value, the gradient value of the vehicle's previous running time, the preset maximum gradient value, the preset minimum gradient value, and the time difference between the previous running time and the current running time.

8. The method according to any one of claims 1 to 6, characterized in that, The method further includes: Based on the road surface adhesion coefficient corresponding to the current operating time of the vehicle, the road surface adhesion level of the current operating time of the vehicle is determined; The real-time yaw moment threshold is determined based on the road surface adhesion level, the vehicle's lateral acceleration and speed at the current operating moment.

9. A vehicle controller, characterized in that, The vehicle controller includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of the method according to any one of claims 1 to 8.

10. A new energy vehicle, characterized in that, Includes the vehicle controller as described in claim 9.

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