Vehicle traction control method, system, program product, medium, and device

Abstract

This application provides a vehicle traction control method, system, program product, medium, and device. The method includes the following steps: acquiring the vehicle's drive motor speed and actual wheel speed; controlling the vehicle's drive torque through feedforward control of the drive motor, and calculating in real time the first vehicle drive torque output through the feedforward control; controlling the vehicle drive torque in parallel through closed-loop control of the traction control system, and calculating in real time the second vehicle drive torque output through the closed-loop control; calculating the minimum value between the first and second vehicle drive torques, and outputting it as the target vehicle drive torque; wherein, the feedforward control involves controlling the rate of change of the vehicle drive torque. This method is beneficial for the rapid response control of traction in electric vehicles under complex road conditions, and can improve vehicle safety and optimize driver's driving experience.

Description

Technical Field

[0001] This application relates to the field of vehicle traction control technology, specifically to a vehicle traction control method, system, computer program product, computer-readable storage medium, and computer device. Background Technology

[0002] A vehicle traction control system (TCS) is used to monitor the slippage of the drive wheels and intervene with torque to prevent excessive wheel slippage when the vehicle starts, accelerates, or travels on low-traction surfaces. This maintains effective grip between the wheels and the road surface, ensuring the vehicle travels smoothly as intended by the driver. Traditional systems and their control strategies are primarily designed around the torque output characteristics and response speed of the internal combustion engine.

[0003] When applied to electric off-road vehicles, the torque response speed of the drive motor is significantly faster than that of the internal combustion engine, which places higher demands on the dynamic adjustment capability of the control system. Existing traction control systems, especially their control logic based on closed-loop feedback, may face challenges in the dynamic adjustment rate and accuracy of torque (including drive and braking torque) when dealing with the drastic and discontinuous changes in adhesion conditions in off-road environments. This may affect the system's control performance and vehicle passability in complex off-road scenarios.

[0004] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] Depending on the specific aspects, one of the problems this application aims to solve is how to optimize the traction control of electric vehicles under complex road conditions.

[0006] In addition, this application aims to solve or alleviate other technical problems existing in the prior art.

[0007] According to one aspect of this application, the following is provided: A vehicle traction control method includes the following steps: Collect the vehicle's drive motor speed and actual wheel speed; The vehicle's drive torque is controlled by the feedforward control of the drive motor, and the first vehicle drive torque output by the feedforward control is calculated in real time. The vehicle drive torque is controlled in parallel through the closed-loop control of the traction control system, and the second vehicle drive torque output through the closed-loop control is calculated in real time. Calculate the minimum value of the first vehicle drive torque and the second vehicle drive torque, and output it as the target vehicle drive torque; The feedforward control involves controlling the rate of change of the vehicle's drive torque.

[0008] According to a second aspect of this application, this application provides a vehicle traction control system, which includes: The data acquisition module collects the vehicle's drive motor speed and actual wheel speed. The feedforward control module controls the vehicle's drive torque through the feedforward control of the drive motor; The closed-loop control module controls the vehicle's drive torque in parallel through the closed-loop control of the traction control system; The calculation module calculates the first vehicle drive torque output by the feedforward control in real time, calculates the second vehicle drive torque output by the closed-loop control in real time, and calculates the minimum value of the first vehicle drive torque and the second vehicle drive torque. The vehicle drive control module outputs the minimum value as the actual vehicle drive torque; The feedforward control involves controlling the rate of change of the vehicle's drive torque.

[0009] According to a third aspect of this application, this application provides a computer program product comprising a computer program that, when executed, implements the vehicle traction control method according to any one of claims 1 to 9.

[0010] According to a fourth aspect of this application, this application provides a computer-readable storage medium on which a computer program is stored, the computer program implementing the vehicle traction control method described above when executed by a processor.

[0011] According to a fifth aspect of this application, this application provides a computer device including a storage module, a processor, and a computer program stored on the storage module and executable on the processor, wherein the processor executes the computer program to implement the vehicle traction control method described above.

[0012] The advantages of this application include at least the following: 1. One embodiment of the vehicle traction control method proposed in this application combines the feedforward control of the drive motor with the closed-loop control of the traction control system. By adjusting the rate of change of the vehicle's drive torque through feedforward control, a rapid response to drive torque control under off-road conditions is achieved, which improves the overall traction control response speed and control accuracy, enabling the vehicle to better adapt to off-road conditions and providing the driver with a better driving feel. 2. The vehicle traction control method proposed in one embodiment of this application takes into account road conditions (such as slope, adhesion coefficient, rolling resistance, etc.) more accurately in the closed-loop control of wheel speed in the traction control system, which improves the control accuracy of traction under off-road conditions and enables the vehicle to better cope with driving scenarios under off-road conditions. 3. The vehicle traction control method proposed in one embodiment of this application can determine whether the vehicle is in the extreme condition of diagonal wheel suspension based on the active suspension travel, and perform timely feedforward control of the drive motor under such extreme conditions to enable the vehicle to return to normal driving state as soon as possible. It can also adjust the vehicle height through active suspension when the wheels slip or get stuck to help the vehicle get out of the road condition. 4. In one embodiment of this application, the vehicle traction control method, when the vehicle is in an uneven working condition and the wheel adhesion is insufficient, controls the steering wheel to make steering fluctuations in conjunction with the EPS system in order to find the wheel traction point, improve wheel adhesion, and thus improve the vehicle's driving characteristics on uneven road conditions. Attached Figure Description

[0013] Referring to the accompanying drawings, the above and other features of this application will become apparent, wherein, Figure 1 A schematic flowchart of a vehicle traction control method according to one embodiment of this application is shown; Figure 2 A schematic diagram of a vehicle traction control system according to one embodiment of this application is shown. Detailed Implementation

[0014] It is readily understood that, based on the technical solution of this application, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of this application. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this application and should not be considered as the entirety of this application or as limitations or restrictions on the technical solution of this application.

[0015] The directional terms such as up, down, left, right, front, back, front, back, top, and bottom mentioned or possibly used in this specification are defined relative to the structures shown in the accompanying drawings. These are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive. Furthermore, the terms "first," "second," "third," and similar expressions are used for descriptive and distinguishing purposes only and should not be construed as indicating or implying the relative importance of the corresponding components or the order of components or assembly sequence.

[0016] refer to Figure 1This diagram illustrates a flow chart of a vehicle traction control method according to one embodiment of this application, where S100-S400 represent various control steps. This vehicle traction control method is particularly suitable for electrically driven vehicles, such as electric vehicles, especially electric off-road vehicles, as it can provide better traction control under off-road conditions, thereby optimizing the vehicle's driving characteristics under off-road conditions and improving the vehicle's handling and driving comfort (especially under complex road conditions). In one embodiment of this application, the method includes the following steps: S100: Collects the vehicle's drive motor speed and actual wheel speed; S200: Control the vehicle's drive torque through feedforward control of the drive motor, and calculate the first vehicle drive torque output through the feedforward control in real time; S300: The vehicle drive torque is controlled in parallel through the closed-loop control of the traction control system, and the second vehicle drive torque output through the closed-loop control is calculated in real time. S400: Calculate the minimum value of the first vehicle drive torque and the second vehicle drive torque, and output it as the target vehicle drive torque; The feedforward control involves controlling the rate of change of the vehicle's drive torque.

[0017] Feedforward control of the drive motor is an advanced control strategy whose core idea is "anticipation and proactive action." It actively counteracts known and predictable disturbances or dynamic changes in the system by calculating and applying a control variable in advance, thereby significantly improving the system's response speed and stability. Feedback control is based on "post-event correction" of errors that have already occurred, while feedforward control is based on "pre-event prevention" of known inputs and targets. In this implementation, the feedforward control of the drive motor is responsible for handling predictable, large dynamic changes, especially responding quickly to abnormal changes in important parameters of the motor itself (such as motor speed, acceleration, and power) to adjust the overall vehicle drive torque. It can match the rapid torque response characteristics of the drive motor, compensating for the insufficient response speed of closed-loop control. The closed-loop control is responsible for eliminating residual errors caused by inaccurate feedforward models and unknown external disturbances (such as sudden load changes), ensuring the final accuracy and stability of the system, thereby guaranteeing accurate traction output and vehicle driving stability.

[0018] In this embodiment, the feedforward control outputs the first vehicle drive torque, the closed-loop control outputs the second vehicle drive torque, and the final output target vehicle drive torque is the smaller of the two. This can reduce traction as much as possible and better prevent wheel slippage. On the other hand, it can prevent possible torque mutations and help the overall vehicle drive torque to have a more stable trend, rather than changing too frequently.

[0019] In one embodiment of this application, the feedforward control includes the following steps: The motor speed change rate is calculated in real time based on the drive motor speed. In response to the motor speed change rate being greater than a preset motor speed change rate threshold, the vehicle drive torque change rate is limited to a preset torque change rate threshold, and the first vehicle drive torque output through the feedforward control is calculated in real time.

[0020] In this embodiment, the input of the drive motor feedforward control is the motor speed change rate, which is obtained by real-time acquisition of the drive motor speed. When the motor speed change rate is too large, especially when it exceeds the preset motor speed change rate threshold, it is determined that the wheel may slip significantly due to excessive drive torque. At this time, the overall vehicle drive torque change rate is immediately limited, especially reduced to the preset torque change rate threshold, in order to achieve the purpose of traction control, avoid wheel slippage in advance, and control the wheel slip rate within the ideal range that can obtain maximum adhesion, thereby achieving a better traction effect.

[0021] Furthermore, in one embodiment of this application, the motor speed change rate threshold includes a plurality of speed change rate level thresholds arranged from smallest to largest, and the torque change rate threshold includes torque change rate level thresholds that are matched one-to-one with the plurality of speed change rate level thresholds. When the motor speed change rate is determined to be greater than the closest specific speed change rate level threshold, the vehicle drive torque change rate is restricted to the torque change rate level threshold that matches the specific speed change rate level threshold.

[0022] In this implementation, the speed change rate is divided into multiple levels by a level threshold. By determining which level the current speed change rate is at, the corresponding vehicle drive torque change rate can be matched. This is beneficial for achieving more precise control of the output, and also helps to prevent torque fluctuations caused by excessive changes in the change rate (especially excessive reductions), which would affect the driver's driving experience.

[0023] In one embodiment of this application, the closed-loop control includes the following steps: Based on the actual wheel speed and the preset target wheel speed, the vehicle drive torque is adjusted to achieve closed-loop control of the actual wheel speed, and the second vehicle drive torque output through closed-loop control is calculated in real time. The preset target wheel speed is related to the vehicle speed and the road surface adhesion coefficient.

[0024] This closed-loop control employs the closed-loop control logic of a traction control system, using a preset target wheel speed as the control objective. For example, PID control is employed as the closed-loop control method to perform closed-loop control on the actual wheel speed. In one embodiment, the preset target wheel speed is calculated, in particular, by summing the actual vehicle speed and a wheel speed compensation amount based on the slip ratio. This wheel speed compensation amount is specifically a speed compensation amount based on the wheel slip ratio and related to the road surface adhesion coefficient, used to compensate for the wheel speed so that the wheel speed remains within the optimal slip ratio range. This wheel speed compensation amount is obtained through vehicle calibration tests and preset in the traction control system, and can be obtained by interpolation using a lookup table based on the current road surface adhesion coefficient and the actual vehicle speed.

[0025] Furthermore, in one embodiment of this application, the method further includes the following steps: Collect the vehicle's current slope gradient, throttle signal, acceleration, and calculate the vehicle's current rolling resistance; The target wheel speed compensation amount is calculated based on the slope, throttle signal, acceleration, and rolling resistance, and then summed to obtain the total target wheel speed compensation amount. The preset target wheel speed is summed with the total target wheel speed compensation amount to obtain the updated target wheel speed. Closed-loop control of the actual wheel speed is achieved by adjusting the vehicle's drive torque based on the actual wheel speed and the updated target wheel speed.

[0026] In this embodiment, considering the complex road conditions and driving situations under off-road conditions, additional parameters are added to compensate for the target wheel speed, ensuring it stays more precisely within the optimal slip ratio range. These parameters include slope gradient, throttle signal, acceleration, and rolling resistance. Compared to driving on normal roads, the frequency of changes in road slope, throttle opening, vehicle acceleration, and rolling resistance is higher under off-road conditions. Calculating the target wheel speed compensation for each of these parameters separately yields greater control benefits. The sum of the target wheel speed compensations obtained for each parameter is used to correct the preset target wheel speed in the previous embodiment, further improving the control accuracy of the traction closed-loop control and achieving a more precise closed-loop control effect.

[0027] In one embodiment of this application, the method further includes the following steps: A vehicle model is established based on current vehicle information and road condition information. The vehicle model includes a vehicle dynamics model and a road surface model. The road surface model includes slope and vehicle adhesion status. The vehicle dynamics model includes motor drive status, front and rear axle support forces, and rolling resistance. Calculate the current front axle limit drive torque and rear axle limit drive torque based on the vehicle model; Calculate the minimum value between the target front axle drive torque and the front axle limit drive torque and output it as the actual front axle drive torque. Calculate the minimum value between the target rear axle drive torque and the rear axle limit drive torque and output it as the actual rear axle drive torque.

[0028] In this implementation, limitations on the ultimate drive torque of the vehicle's front and rear axles are provided outside of the traction control logic. Here, "ultimate drive torque" refers to the actual maximum drive torque that the front or rear axle can output under current road conditions (primarily dependent on axle load and maximum road adhesion coefficient). In off-road conditions, especially on extreme inclines, the vehicle's axle load undergoes significant shifts, which can affect the load distribution of the front and rear axles, thus impacting their ultimate drive torque and preventing it from matching the target front or rear axle drive torque output by the traction control system. In this case, it is necessary to first obtain road conditions, vehicle drive information, and load distribution. In this implementation, a road model is specifically established based on the gradient (which can be used to calculate the vehicle's gravitational component along the slope) and adhesion status (e.g., road adhesion coefficient). A vehicle model is established based on the motor drive status (especially motor speed, maximum motor power, etc.), the front and rear axle support forces (especially reflecting axle load shift), and rolling resistance. Finally, the ultimate drive torque of the front and rear axles is calculated comprehensively using both the vehicle dynamics model and the road model. This method of calculating the ultimate driving torque takes into account the axle load transfer between the front and rear axles under different gradients or uneven road conditions. It can calculate the ultimate driving torque that is more consistent with the current road conditions for the front and rear axles, and thus limit the magnitude of the target front and rear axle driving torque. This prevents the target front and rear axle driving torque output by feedforward control and closed-loop control from exceeding the ultimate driving torque, reducing the possibility of the vehicle getting into dangerous situations such as severe wheel slippage, loss of steering control, or wheel jamming. This is especially important in off-road conditions with extremely complex road conditions.

[0029] In one embodiment of this application, the method further includes the following steps: Collect the suspension travel of each wheel and determine whether it is compression or extension travel; In response to two diagonal wheels being in compression stroke and the other two diagonal wheels being in extension stroke, the rate of change of the overall vehicle drive torque is limited to the preset torque change rate threshold.

[0030] In off-road conditions, vehicles may experience a "wheel-on-wheel suspension" situation, where one or two wheels are suspended across a cross axle or diagonally. This is a more extreme and complex typical off-road dangerous situation than a single wheel suspension. It thoroughly tests a vehicle's ability to distribute power between axles and wheels. In this situation, even though two wheels have perfect traction, due to the dual loss of power between axles and wheels, they receive almost no effective torque, and the vehicle becomes completely stuck. Therefore, rapid control of the vehicle's drive torque is crucial in this "wheel-on-wheel suspension" situation. In this implementation, the vehicle's "wheel-on-wheel suspension" situation is first determined by the active suspension travel of each wheel. When two diagonally opposite wheels are in compression travel and the other two diagonally opposite wheels are in extension travel, the vehicle is likely to be stuck in this situation. At this point, the feedforward control of the drive motor is directly executed, and the slope of the motor speed is not considered; instead, the rate of change of the vehicle's drive torque is directly limited. This is because the core of getting out of a "wheel-on-wheel suspension" situation is "electronic limited-slip differential," which transfers torque by applying braking to the spinning wheels. This process requires a certain amount of time (such as braking system decompression time, sensor detection and logic judgment time, etc.). If the rate of change of the vehicle's driving torque is too high, then before the electronic limited-slip system can fully take effect, the huge torque will instantly surge to the path of least resistance—that is, the suspended wheels—causing them to spin rapidly. This wastes power before the electronic control system can establish effective distribution, and the vehicle may suddenly lurch forward and then quickly lose power, or even suffer impact, damage, or further getting stuck due to the wheels violently spinning and hitting the ground. Reducing the rate of change of the vehicle's driving torque provides a "buffer window" for the entire electronic control system, allowing braking intervention to occur synchronously with or even ahead of the torque increase. This achieves "torque guidance" rather than "torque chasing," allowing the system to more calmly and accurately distribute the gradually increasing torque to the wheels with traction in real time. In addition, on off-road surfaces (such as mud, sand, and rocks), the adhesion of the wheels with traction is itself limited, fragile, and non-linear. Reducing the rate of change of driving torque prevents the wheels from spinning violently, avoiding damage to the precious and unstable wheel adhesion points. It also brings linear and predictable vehicle dynamics, giving the driver more confidence and protecting the vehicle's mechanical components.

[0031] In one embodiment of this application, the method further includes the following steps: Collect data on vehicle throttle opening and speed; In response to the throttle opening being greater than a preset opening threshold and the vehicle speed being less than a preset vehicle speed threshold, it is determined whether the actual wheel speed is greater than a preset wheel speed threshold. In response to the actual wheel speed being greater than a preset wheel speed threshold, the active suspension of each wheel is controlled to lower the vehicle body. In response to the actual wheel speed not exceeding the preset wheel speed threshold, the active suspension of each wheel is controlled to raise the vehicle body, and after the vehicle body is raised, the vehicle is controlled to downshift and increase torque.

[0032] This implementation primarily considers situations where a vehicle is unable to move forward due to wheel slippage or wheel jamming. First, it determines whether the vehicle is in this situation by checking the throttle opening and vehicle speed. The basic logic is as follows: if the throttle opening is large, especially exceeding a large throttle opening threshold (i.e., a preset throttle opening threshold), it proves that the driver has a clear intention to move forward. However, if the vehicle speed is still very low, especially below a very small speed threshold (i.e., the preset speed threshold), it proves that the vehicle is essentially unable to move forward, and it can be basically determined that this is caused by wheel slippage or wheel jamming. Then, the wheel speed is assessed. If the wheel still has a high wheel speed, especially exceeding the preset wheel speed threshold, it is determined that the wheel is slipping. At this point, the active suspension is controlled to actively move its travel, especially controlling the active suspension to lower the vehicle height. For example, the active suspension is immediately controlled to press down with maximum downforce, thereby better finding the traction point and allowing the ground to provide some traction, helping the vehicle to overcome the slippage. If a wheel has a low or even zero rotational speed, especially below a preset wheel speed threshold, it is determined that the wheel is stuck and cannot rotate. In this case, the active suspension is controlled to actively increase its travel, particularly to raise the vehicle's height. For example, the active suspension can be immediately raised with maximum lifting force to increase ground clearance and improve vehicle passability. Once the vehicle height has increased, the vehicle is immediately downshifted to increase torque, especially to a high-torque gear, increasing wheel grip so that the vehicle has sufficient torque to drive over obstacles at full power. This control method, combined with active suspension travel control, effectively handles situations where the vehicle is slipping or the wheels are stuck, reducing the need for stopping or external assistance.

[0033] In one embodiment of this application, the method further includes the following steps: The suspension parameters and wheel dynamics of each wheel are collected in real time, including wheel acceleration and slip ratio. Based on the suspension parameters and wheel dynamics, determine whether the current road condition belongs to a preset set of uneven road conditions and whether the wheel adhesion is lower than a preset adhesion threshold. In response to the current road conditions belonging to a preset set of uneven road conditions and the wheel adhesion being lower than a preset adhesion threshold, the EPS system performs left and right steering fluctuations with a preset steering angle fluctuation amount, and collects the wheel adhesion in real time during the fluctuation process. The left and right steering fluctuations stop when the wheel adhesion exceeds a preset adhesion threshold.

[0034] In this implementation, wheel grip control is achieved through fine-tuning the steering using the EPS (Electric Power Steering) system, enabling the vehicle to maintain sufficient traction in off-road conditions. First, suspension parameters and wheel dynamics are collected to comprehensively assess the current road conditions. In another implementation, road conditions can be determined by image recognition of the road surface captured by a vehicle camera, or by road information provided by an ADAS (Advanced Driver Assistance Systems) system. Road condition assessment is achieved by checking whether the current road condition matches any condition in a preset set of uneven road conditions. If the current road condition is determined to belong to the preset set of uneven road conditions, then the wheel grip is assessed to determine if it is low, especially below a preset grip threshold (of course, both can be performed simultaneously). If, on the one hand, the vehicle's current road conditions fall within a preset set of uneven road conditions, and on the other hand, the wheel adhesion is below a preset adhesion threshold, then it is necessary to intervene in steering via EPS. In this case, the EPS first performs left and right steering fluctuations with a preset steering angle fluctuation amount. During the fluctuation, the wheel adhesion is collected in real time. Then, when the wheel adhesion exceeds the preset adhesion threshold, the left and right steering fluctuations are stopped, and the steering wheel angle remains at its current position. This allows for the dynamic and road-condition-matched finding of the highest point of adhesion between the wheel and the road surface, providing sufficient adhesion to the wheel. This control method provides a control strategy that adjusts wheel adhesion by continuously fine-tuning the steering while the vehicle is in motion, without changing the vehicle's traction or braking force. It is particularly effective in achieving good adhesion adjustment in complex road conditions, increasing wheel grip.

[0035] In summary, the vehicle traction control method proposed in one embodiment of this application combines the feedforward control of the drive motor with the closed-loop control of the traction control system. By controlling the motor, the response speed of the traction control is improved, and by using closed-loop control, the control accuracy of the traction control is guaranteed. This allows the vehicle to better adapt to off-road conditions, improving driving safety under complex road conditions while also providing the driver with a better driving feel.

[0036] The second aspect of this application proposes a vehicle traction control system. (Reference) Figure 2 This diagram illustrates a module schematic of a vehicle traction control system according to one embodiment of the present application. The control system 10 includes: The data acquisition module 100 collects the speed of the vehicle's drive motor and the actual wheel speed. The feedforward control module 200 controls the vehicle's drive torque through feedforward control of the drive motor. The closed-loop control module 300 controls the vehicle's drive torque in parallel through the closed-loop control of the traction control system. The calculation module 400 calculates the first vehicle drive torque output by the feedforward control module in real time, calculates the second vehicle drive torque output by the closed-loop control module in real time, and calculates the minimum value of the first vehicle drive torque and the second vehicle drive torque. The vehicle drive control module 500 outputs the minimum value as the actual vehicle drive torque. The feedforward control involves controlling the rate of change of the vehicle's drive torque.

[0037] In one embodiment of this application, the calculation module calculates the motor speed change rate in real time based on the drive motor speed; the feedforward control module, in response to the motor speed change rate being greater than a preset motor speed change rate threshold, limits the vehicle drive torque change rate to a preset torque change rate threshold, and the calculation module calculates the first vehicle drive torque output through the feedforward control in real time.

[0038] In one embodiment of this application, the motor speed change rate threshold includes multiple speed change rate level thresholds arranged from smallest to largest, and the torque change rate threshold includes torque change rate level thresholds that are matched one-to-one with the multiple speed change rate level thresholds. When the motor speed change rate is determined to be greater than the closest specific speed change rate level threshold, the vehicle drive torque change rate is limited to the torque change rate level threshold that matches the specific speed change rate level threshold.

[0039] In one embodiment of this application, the closed-loop control module achieves closed-loop control of the actual wheel speed by adjusting the vehicle drive torque based on the actual wheel speed and the preset target wheel speed, and the calculation module calculates the second vehicle drive torque output through the closed-loop control in real time; wherein, the preset target wheel speed is related to the vehicle speed and the road surface adhesion coefficient.

[0040] In one embodiment of this application, the acquisition module acquires the vehicle's current slope, throttle signal, and acceleration, and the calculation module calculates the vehicle's current rolling resistance; The calculation module calculates the target wheel speed compensation amount based on the slope, throttle signal, acceleration, and rolling resistance, and sums them to obtain the total target wheel speed compensation amount; the preset target wheel speed is summed with the total target wheel speed compensation amount to obtain the updated target wheel speed; The closed-loop control module achieves closed-loop control of the actual wheel speed by adjusting the vehicle's drive torque based on the actual wheel speed and the updated target wheel speed.

[0041] In one embodiment of this application, the calculation module establishes a vehicle model based on current vehicle information and road condition information. The vehicle model includes a vehicle dynamics model and a road surface model, wherein the road surface model includes slope and vehicle adhesion state, and the vehicle dynamics model includes motor drive state, front and rear axle support forces, and rolling resistance. The calculation module calculates the current front axle limit drive torque and rear axle limit drive torque based on the vehicle model. The calculation module calculates the minimum value between the target front axle drive torque and the front axle limit drive torque, and outputs it as the actual front axle drive torque through the vehicle drive control module. The calculation module also calculates the minimum value between the target rear axle drive torque and the rear axle limit drive torque, and outputs it as the actual rear axle drive torque through the vehicle drive control module.

[0042] In one embodiment of this application, the acquisition module acquires the suspension travel of each wheel and determines whether it is a compression travel or a tension travel; The feedforward control module responds to the compression stroke of two diagonal wheels and the extension stroke of the other two diagonal wheels, limiting the rate of change of the overall vehicle driving torque to the preset torque change rate threshold.

[0043] In one embodiment of this application, a suspension control module and a gear adjustment module are also included; The acquisition module collects the vehicle's throttle opening and speed; The calculation module responds to the throttle opening being greater than a preset opening threshold and the vehicle speed being less than a preset vehicle speed threshold by determining whether the actual wheel speed is greater than a preset wheel speed threshold. The suspension control module responds to the actual wheel speed being greater than a preset wheel speed threshold by controlling the active suspension of each wheel to lower the vehicle body; and responds to the actual wheel speed being less than the preset wheel speed threshold by controlling the active suspension of each wheel to raise the vehicle body. Furthermore, the gear adjustment module controls the vehicle to downshift and increase torque after the vehicle body has been raised.

[0044] In one embodiment of this application, an EPS control module is also included; The acquisition module collects the suspension parameters and wheel dynamics of each wheel in real time, including wheel acceleration and slip ratio. The calculation module determines whether the current road condition belongs to a preset set of uneven road conditions and whether the wheel adhesion is lower than a preset adhesion threshold based on the suspension parameters and wheel dynamics. The EPS control module responds to the current road conditions belonging to a preset set of uneven road conditions and the wheel adhesion being lower than a preset adhesion threshold by controlling the EPS system to perform left and right steering fluctuations with a preset steering angle fluctuation amount. The acquisition module collects the wheel adhesion in real time during the fluctuation process. The EPS control module controls the EPS system to stop the left and right steering fluctuations when the wheel adhesion is greater than a preset adhesion threshold.

[0045] The vehicle traction control system has all the beneficial technical effects of the aforementioned vehicle traction control method, which will not be elaborated here.

[0046] A third aspect of this application provides a computer program product, including a computer program that, when executed, implements the vehicle traction control method described above.

[0047] A fourth aspect of this application provides a computer-readable storage medium on which a computer program is stored, which, when executed by a processor, implements the vehicle traction control method described above.

[0048] The fifth aspect of this application provides a computer device including a storage module, a processor, and a computer program stored on the storage module and executable on the processor, wherein the processor executes the computer program to implement the vehicle traction control method described above.

[0049] Those skilled in the art will understand that all or part of the processes in the vehicle traction control method of this application can be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which includes, but is not limited to, program code for executing the aforementioned vehicle traction control method. For ease of explanation, only the parts relevant to this application are shown. The computer program code can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable storage medium can include any entity or device capable of carrying the computer program code, a medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory, a random access memory, an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc. It should be noted that the content contained in the computer-readable storage medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable storage medium does not include electrical carrier signals and telecommunication signals.

[0050] It should be understood that all the above preferred embodiments are exemplary and not restrictive, and various modifications or variations made by those skilled in the art to the specific embodiments described above under the concept of this application should be within the scope of legal protection of this application.

Claims

1. A vehicle traction control method, characterized in that, Includes the following steps: Collect the vehicle's drive motor speed and actual wheel speed; The vehicle's drive torque is controlled by the feedforward control of the drive motor, and the first vehicle drive torque output by the feedforward control is calculated in real time. The vehicle drive torque is controlled in parallel through the closed-loop control of the traction control system, and the second vehicle drive torque output through the closed-loop control is calculated in real time. Calculate the minimum value of the first vehicle drive torque and the second vehicle drive torque, and output it as the target vehicle drive torque; The feedforward control involves controlling the rate of change of the vehicle's drive torque.

2. The vehicle traction control method according to claim 1, characterized in that, The feedforward control includes the following steps: The motor speed change rate is calculated in real time based on the drive motor speed. In response to the motor speed change rate being greater than a preset motor speed change rate threshold, the vehicle drive torque change rate is limited to a preset torque change rate threshold, and the first vehicle drive torque output through the feedforward control is calculated in real time.

3. The vehicle traction control method according to claim 2, characterized in that, The motor speed change rate threshold includes multiple speed change rate level thresholds arranged from smallest to largest. The torque change rate threshold includes torque change rate level thresholds that are matched one-to-one with the multiple speed change rate level thresholds. When the motor speed change rate is determined to be greater than the closest specific speed change rate level threshold, the vehicle drive torque change rate is restricted to the torque change rate level threshold that matches the specific speed change rate level threshold.

4. The vehicle traction control method according to claim 1, characterized in that, The closed-loop control includes the following steps: Based on the actual wheel speed and the preset target wheel speed, the vehicle drive torque is adjusted to achieve closed-loop control of the actual wheel speed, and the second vehicle drive torque output through closed-loop control is calculated in real time. The preset target wheel speed is related to the vehicle speed and the road surface adhesion coefficient.

5. The vehicle traction control method according to claim 4, characterized in that, Includes the following steps: Collect the vehicle's current slope gradient, throttle signal, acceleration, and calculate the vehicle's current rolling resistance; The target wheel speed compensation amount is calculated based on the slope, throttle signal, acceleration, and rolling resistance, and then summed to obtain the total target wheel speed compensation amount. The preset target wheel speed is summed with the total target wheel speed compensation amount to obtain the updated target wheel speed. Closed-loop control of the actual wheel speed is achieved by adjusting the vehicle's drive torque based on the actual wheel speed and the updated target wheel speed.

6. The vehicle traction control method according to claim 1, characterized in that, Includes the following steps: A vehicle model is established based on current vehicle and road condition information. The vehicle model includes a vehicle dynamics model and a road surface model. The road surface model includes slope and vehicle adhesion status. The vehicle dynamics model includes motor drive status, front and rear axle support forces, and rolling resistance. Calculate the current front axle limit drive torque and rear axle limit drive torque based on the vehicle model; Calculate the minimum value between the target front axle drive torque and the front axle limit drive torque and output it as the actual front axle drive torque. Calculate the minimum value between the target rear axle drive torque and the rear axle limit drive torque and output it as the actual rear axle drive torque.

7. The vehicle traction control method according to claim 2, characterized in that, Includes the following steps: Collect the suspension travel of each wheel and determine whether it is compression or extension travel; In response to two diagonal wheels being in compression stroke and the other two diagonal wheels being in extension stroke, the rate of change of the overall vehicle drive torque is limited to the preset torque change rate threshold.

8. The vehicle traction control method according to claim 1, characterized in that, Includes the following steps: Collect data on vehicle throttle opening and speed; In response to the throttle opening being greater than a preset opening threshold and the vehicle speed being less than a preset vehicle speed threshold, it is determined whether the actual wheel speed is greater than a preset wheel speed threshold. In response to the actual wheel speed being greater than a preset wheel speed threshold, the active suspension of each wheel is controlled to lower the vehicle body. In response to the actual wheel speed not exceeding the preset wheel speed threshold, the active suspension of each wheel is controlled to raise the vehicle body, and after the vehicle body is raised, the vehicle is controlled to downshift and increase torque.

9. The vehicle traction control method according to claim 1, characterized in that, Includes the following steps: The suspension parameters and wheel dynamics of each wheel are collected in real time, including wheel acceleration and slip ratio. Based on the suspension parameters and wheel dynamics, determine whether the current road condition belongs to a preset set of uneven road conditions and whether the wheel adhesion is lower than a preset adhesion threshold. In response to the current road conditions belonging to a preset set of uneven road conditions and the wheel adhesion being lower than a preset adhesion threshold, the EPS system performs left and right steering fluctuations with a preset steering angle fluctuation amount, and collects the wheel adhesion in real time during the fluctuation process. The left and right steering fluctuations stop when the wheel adhesion exceeds a preset adhesion threshold.

10. A vehicle traction control system, characterized in that, include: The data acquisition module collects the vehicle's drive motor speed and actual wheel speed. The feedforward control module controls the vehicle's drive torque through the feedforward control of the drive motor; The closed-loop control module controls the vehicle's drive torque in parallel through the closed-loop control of the traction control system; The calculation module calculates the first vehicle drive torque output by the feedforward control in real time, calculates the second vehicle drive torque output by the closed-loop control in real time, and calculates the minimum value of the first vehicle drive torque and the second vehicle drive torque. The vehicle drive control module outputs the minimum value as the actual vehicle drive torque; The feedforward control involves controlling the rate of change of the vehicle's drive torque.

11. A computer program product, comprising a computer program, characterized in that, When the computer program is executed, it implements the vehicle traction control method according to any one of claims 1 to 9.

12. A computer-readable storage medium on which a computer program is stored, characterized in that, When the computer program is executed by the processor, it implements the vehicle traction control method according to any one of claims 1 to 9.

13. A computer device comprising a storage module, a processor, and a computer program stored on the storage module and executable on the processor, characterized in that, When the processor executes the computer program, it implements the vehicle traction control method according to any one of claims 1 to 9.

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