A vehicle hill hold control method and apparatus

Abstract

The application discloses a vehicle hill-hold anti-slip control method and device, and the method comprises the following steps: determining a basic driving torque and a basic braking torque when a vehicle is in a steady hill-hold state; determining a maximum slip ratio of the vehicle based on a reference speed of the vehicle and wheel speeds of each wheel; wherein the reference speed is an estimated value of a longitudinal motion speed of the vehicle; if the vehicle appears wheel slip, obtaining an updated driving torque and an updated braking torque based on the maximum slip ratio, the basic driving torque and the basic braking torque; controlling the driving torque of the vehicle to be the updated driving torque and the braking torque to be the updated braking torque. The method can effectively identify and inhibit the wheel slip trend of the vehicle in the steady hill-hold state, avoid rapid hill sliding caused by the wheel breaking through the adhesion limit, and improve the hill-hold safety of the vehicle.

Description

Technical Field

[0001] This invention relates to the field of vehicle control technology, and in particular to a method and device for controlling vehicle anti-skid on slopes. Background Technology

[0002] Currently, with the continuous development of the automotive industry, vehicle safety and intelligence have increasingly become the focus of user attention. Among them, hill start assist or hill-start assist function, as an important driving assistance technology, has been widely used in various vehicle models. This function aims to prevent the vehicle from rolling backward due to gravity when it is parked on a slope by actively applying driving or braking force, thereby improving driving convenience and safety.

[0003] However, existing slope control solutions primarily focus on maintaining a reference vehicle speed of zero, without fully considering the adhesion limits between the wheels and the road surface. When a vehicle is parked on a slope with a low coefficient of friction (such as mud, ice, or compacted snow) or a steep incline, the drive wheels continuously experience significant driving torque. Once this torque exceeds the adhesion limits provided by the road surface, the wheels will slip (i.e., the wheels will spin). This wheel spin will further reduce the coefficient of friction between the vehicle and the road surface, causing the vehicle to lose longitudinal stability and fail to provide effective parking torque. Ultimately, this can lead to the vehicle rolling backward rapidly, and in extreme cases, even causing lateral deviation, posing a serious safety hazard.

[0004] Therefore, how to effectively identify and suppress the wheel slippage tendency of a vehicle in a steady-state parking slope, avoid rapid roll-off caused by the wheel exceeding the adhesion limit, and improve the parking safety of the vehicle has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] In order to effectively identify and suppress the wheel slippage tendency of a vehicle in a steady-state parking slope, avoid rapid roll-off caused by the wheels exceeding the adhesion limit, and improve the parking safety of the vehicle, this invention provides a vehicle parking slope anti-skid control method and device.

[0006] In a first aspect, embodiments of the present invention provide a vehicle hill-start assist control method, which may include: Determine the basic driving torque and basic braking torque of the vehicle when it is in a steady-state parking position on a slope; The maximum slip ratio of the vehicle is determined based on the reference vehicle speed and the wheel speed of each wheel; wherein the reference vehicle speed is an estimated value of the longitudinal speed of the vehicle. If the vehicle experiences wheel slippage, then based on the maximum slip ratio, the basic drive torque, and the basic braking torque, updated drive torque and updated braking torque are obtained. The driving torque of the vehicle is controlled to be the updated driving torque, and the braking torque is controlled to be the updated braking torque.

[0007] In one or more optional embodiments of this application, if the vehicle experiences wheel slippage, obtaining updated drive torque and updated braking torque based on the maximum slip ratio, the basic drive torque, and the basic braking torque includes: If the vehicle experiences wheel slippage, a drive torque correction coefficient is determined based on the maximum slip ratio; wherein the drive torque correction coefficient is a value between (0,1); Based on the drive torque correction coefficient, the base drive torque, and the base braking torque, the updated drive torque and the updated braking torque are obtained.

[0008] In one or more optional embodiments of this application, obtaining the updated drive torque and updated braking torque based on the drive torque correction coefficient, the base drive torque, and the base braking torque includes: The updated drive torque is determined based on the drive torque correction coefficient and the base drive torque; Based on the updated drive torque and the base drive torque, a torque correction value is determined; The updated braking torque is determined based on the torque correction value and the base braking torque.

[0009] In one or more optional embodiments of this application, determining the maximum slip ratio of the vehicle based on the reference vehicle speed and the wheel speeds of each wheel includes: The maximum wheel speed is defined as the maximum wheel speed among all the wheel speeds in the vehicle. The maximum slip ratio is obtained based on the maximum wheel speed and the reference vehicle speed.

[0010] In one or more optional embodiments of this application, after determining the updated drive torque and updated braking torque based on the maximum slip ratio, the basic drive torque, and the basic braking torque if wheel slip occurs in the vehicle, the method further includes: If the updated braking torque is greater than the vehicle's maximum braking torque, then the maximum braking torque is used as the updated braking torque.

[0011] In one or more optional embodiments of this application, wheel slippage of the vehicle is determined by the following method: If the maximum slip ratio is greater than the preset slip threshold, then it is determined that the vehicle has wheel slippage.

[0012] In one or more optional embodiments of this application, determining the basic driving torque and basic braking torque when the vehicle is steadily parking on a slope includes: If the vehicle needs to be in a steady-state parking position, determine the total parking torque required for the vehicle; The distribution ratios of driving torque and braking torque are determined based on the slope of the slope where the vehicle is located. The base drive torque and base braking torque are determined based on the distribution ratios of the total parking torque and the drive torque and braking torque, respectively.

[0013] In one or more optional embodiments of this application, after determining the base drive torque and base braking torque based on the distribution ratios corresponding to the total parking torque and the drive torque and braking torque, the method further includes: The driving torque of the vehicle is controlled to be the basic driving torque, and the braking torque is controlled to be the basic braking torque.

[0014] In one or more optional embodiments of this application, the following further includes: If the vehicle's drive motor or braking system is limited, causing the drive torque to fail to reach the base drive torque or the braking torque to fail to reach the base braking torque, the base drive torque and the base braking torque are dynamically adjusted, ensuring that the sum of the adjusted base drive torque and the base braking torque is still equal to the total parking torque.

[0015] Secondly, embodiments of the present invention provide a vehicle hill-start assist control device, which may include: The first determining module is used to determine the basic driving torque and basic braking torque of the vehicle when it is steadily parking on a slope. The second determining module is used to determine the maximum slip ratio of the vehicle based on the reference vehicle speed and the wheel speed of each wheel; wherein the reference vehicle speed is an estimated value of the longitudinal movement speed of the vehicle. An update module is used to obtain an updated drive torque and an updated braking torque based on the maximum slip ratio, the basic drive torque, and the basic braking torque if the vehicle experiences wheel slippage. The control module is used to control the vehicle's drive torque to the updated drive torque and braking torque to the updated braking torque.

[0016] Thirdly, embodiments of the present invention provide a computer-readable storage medium having a computer program / instruction stored thereon, which, when executed by a processor, implements the vehicle parking slope anti-skid control method as described above.

[0017] Fourthly, embodiments of the present invention provide a computer program product, including a computer program / instruction, which, when executed by a processor, implements the vehicle parking slope anti-skid control method as described above.

[0018] Fifthly, embodiments of the present invention provide a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the vehicle parking slope anti-skid control method as described above.

[0019] The beneficial effects of the above-described technical solutions provided in the embodiments of the present invention include at least the following: This invention provides a vehicle anti-skid control method for parking on slopes. This method monitors the vehicle's reference speed and the wheel speed of each wheel in real time, and can accurately calculate the maximum slip ratio of the vehicle when parking on a steady slope. If wheel slip is detected, the driving torque and braking torque are dynamically updated based on the maximum slip ratio. This allows for timely adjustment of power output and braking force distribution at the critical moment when the wheel is about to exceed the road surface adhesion limit, thereby effectively suppressing the wheel slipping trend and preventing the wheel from completely losing adhesion due to excessive slip. Compared with traditional slope control methods that only aim to maintain the reference speed at zero, this method can effectively solve the problem of rapid vehicle roll-off caused by wheel spin, and significantly improve the safety and stability of vehicle parking on slopes with low adhesion coefficients.

[0020] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0021] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0022] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 A flowchart illustrating the vehicle anti-skid control method for parking on slopes provided in an embodiment of the present invention; Figure 2 A schematic diagram of a framework for an example of a vehicle control module provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the vehicle hill-start assist control device provided in an embodiment of the present invention. Detailed Implementation

[0023] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0024] The inventors discovered that existing slope control schemes primarily focus on maintaining a reference vehicle speed of zero, without adequately considering the adhesion limits between the wheels and the road surface. When a vehicle is parked on a slope with a low coefficient of friction (such as mud, ice, or compacted snow) or a steep incline, the drive wheels continuously experience significant driving torque. Once this torque exceeds the adhesion limits provided by the road surface, the wheels will slip (i.e., the wheels will spin). This wheel spin further reduces the coefficient of friction between the vehicle and the road surface, causing the vehicle to lose longitudinal stability and fail to provide effective slope-holding torque. Ultimately, this leads to the vehicle rapidly rolling downhill, and in extreme cases, even causing lateral deviation, posing a serious safety hazard. Based on this, the inventors, through further research and development, created this invention, providing a vehicle slope-holding anti-skid control method and device.

[0025] Example 1 Embodiment 1 of the present invention provides a method for controlling vehicle anti-skid on a parking slope, referring to... Figure 1 As shown, the method may include the following steps S101-S104: S101: Determine the basic driving torque and basic braking torque when the vehicle is steadily parked on a slope.

[0026] S102: Determine the maximum slip ratio of the vehicle based on the vehicle's reference speed and the wheel speeds of each wheel. The reference speed is an estimate of the vehicle's longitudinal speed.

[0027] S103: If the vehicle experiences wheel slippage, the updated drive torque and updated braking torque are obtained based on the maximum slip ratio, the basic drive torque, and the basic braking torque.

[0028] S104: Control the vehicle's drive torque to update the drive torque and braking torque to update the braking torque.

[0029] This invention provides a vehicle anti-skid control method for parking on slopes. This method monitors the vehicle's reference speed and the wheel speed of each wheel in real time, and can accurately calculate the maximum slip ratio of the vehicle when parking on a steady slope. If wheel slip is detected, the driving torque and braking torque are dynamically updated based on the maximum slip ratio. This allows for timely adjustment of power output and braking force distribution at the critical moment when the wheel is about to exceed the road surface adhesion limit, thereby effectively suppressing the wheel slipping trend and preventing the wheel from completely losing adhesion due to excessive slip. Compared with traditional parking control methods that only aim to maintain the reference speed at zero, this method can effectively solve the problem of rapid vehicle roll-off caused by wheel spin, and significantly improve the safety and stability of vehicle parking on slopes with low adhesion coefficients.

[0030] In step S101 above, the basic driving torque and basic braking torque of the vehicle during steady-state parking on a slope are determined. Specifically, this includes the following steps S1011-S1013: S1011: If the vehicle needs to be in a steady-state parking position, determine the total parking torque required for the vehicle.

[0031] Specifically, when the preset conditions for activating the hill-holding function are met, such as detecting that the vehicle is on a slope and the vehicle speed is below a certain threshold, and that the accelerator pedal and brake pedal are both not depressed, or using other triggering logic depending on the vehicle configuration, it can be determined that it is necessary to enter the steady-state hill-holding mode.

[0032] It should be noted that the steady-state parking described in this method refers to the parking state with a reference vehicle speed of 0 km / h. The reference vehicle speed is an estimated value used to characterize the longitudinal speed of the vehicle body, calculated in real time by the vehicle control system based on wheel speed signals and vehicle acceleration signals; it is not necessarily equivalent to the actual longitudinal speed of the vehicle.

[0033] After entering steady-state parking mode, the total parking torque required to keep the vehicle stationary on the slope is first calculated. The total parking torque can be obtained by combining the tangential component torque due to gravity and the speed control torque based on proportional-integral control (PI).

[0034] The tangential component torque due to gravity is a theoretical torque value calculated based on the slope gradient and estimated vehicle mass, used to counteract the component of gravity along the slope. The PI-based speed control torque, calculated in real-time by the PI controller with a reference vehicle speed of zero as the control target, is a corrected torque value used to eliminate speed control deviations, providing fine-tuning force to prevent rollback / lurching and ensuring the vehicle remains stationary on the slope. Adding these two torque components together yields the total parking torque required for the vehicle.

[0035] S1012: Determine the distribution ratio of driving torque and braking torque according to the slope of the slope where the vehicle is located.

[0036] Specifically, after determining the total parking torque, it is necessary to reasonably distribute the total parking torque to the motor controller and the braking control system for joint execution. When the slope is small, steady-state parking can generally be accomplished by relying solely on the drive torque; when the slope is large, steady-state parking requires the drive torque and braking torque to be used together in a certain distribution ratio to address the temperature rise problem caused by relying solely on the drive torque when the total parking torque is large.

[0037] Obtain the vehicle's calibrated slope-distribution ratio table. Based on the slope of the slope where the vehicle is located, determine the basic driving torque / total parking torque and basic braking torque / total parking torque corresponding to the current slope in the slope-distribution ratio table. These are the distribution ratios corresponding to the driving torque and braking torque, respectively.

[0038] Different vehicle models should correspond to different slope-distribution ratio tables. In one specific embodiment, a slope-distribution ratio correspondence table is shown in Table 1 below.

[0039] Table 1 Slope-Distribution Ratio Table

[0040] Based on the slope-distribution ratio table shown in Table 1 above, when the slope of the vehicle is 40%, the corresponding basic driving torque / total parking torque is 80%, and the basic braking torque / total parking torque is 20%. That is, at this time, the distribution ratio of driving torque is 80%, and the distribution ratio of braking torque is 20%.

[0041] S1013: Determine the basic drive torque and basic braking torque based on the distribution ratios of the total parking torque, drive torque, and braking torque.

[0042] Specifically, after determining the total parking torque and the corresponding distribution ratios of driving torque and braking torque, the specific values ​​of the basic driving torque and basic braking torque can be calculated so that the sum of the two equals the total parking torque.

[0043] The specific calculation method is as follows: multiply the total parking torque by the distribution ratio of the driving torque to obtain the basic driving torque; multiply the total parking torque by the distribution ratio of the braking torque to obtain the basic braking torque.

[0044] In this embodiment of the application, after completing step S1013, the following steps S1014-S1015 are also included: S1014: Controls the vehicle's driving torque based on the driving torque and braking torque based on the braking torque.

[0045] Specifically, after calculating the basic drive torque and basic braking torque, preliminary control is first performed based on these results. A drive torque request command is sent to the motor controller, requesting the drive motor to output a drive torque equal to the basic drive torque; simultaneously, a braking torque request command is sent to the braking control system, requesting the braking control system to output a braking torque equal to the basic braking torque. During the control process, the actual drive torque fed back from the motor controller and the actual braking torque fed back from the braking control system are received in real time, forming a closed-loop control to ensure that the actual execution result is consistent with the request command.

[0046] By combining the driving torque and braking torque, the total parking torque is provided to the vehicle, enabling the vehicle to maintain a steady stop on a slope.

[0047] S1015: If the vehicle's drive motor or braking system is limited, causing the drive torque to fail to reach the basic drive torque or the braking torque to fail to reach the basic braking torque, the basic drive torque and basic braking torque will be dynamically adjusted, and the sum of the adjusted basic drive torque and basic braking torque will still be equal to the total parking torque.

[0048] Specifically, during actual control, the drive motor or braking control system may experience limitations in its capabilities due to temperature rise, malfunctions, or other reasons. For example, prolonged high-torque output by the drive motor may cause temperature rise, triggering power reduction protection, resulting in the actual maximum output drive torque being lower than the basic drive torque; or the braking system may experience a lower actual maximum output braking torque than the basic braking torque due to hydraulic failures, overheating, or other reasons.

[0049] When the aforementioned functional limitations occur, the distribution of basic drive torque and basic braking torque needs to be dynamically adjusted. The principle of adjustment is that, based on the limited party's maximum torque output capacity, the other party supplements the remaining torque demand, ensuring that the sum of the adjusted basic drive torque and basic braking torque still equals the total parking torque.

[0050] For example, if the drive motor's function is limited, and the maximum drive torque it can provide is less than the base drive torque, then the base drive torque will be adjusted to the maximum drive torque the drive motor can provide at this time. Simultaneously, the base braking torque will be adjusted to the difference between the total parking torque and the base drive torque. Similarly, if the braking control system is limited, the opposite adjustment will be made.

[0051] The base driving torque and base braking torque obtained after the above dynamic adjustment are still referred to as base driving torque and base braking torque in this method, and are used as the reference values ​​for subsequent slip ratio correction.

[0052] In step S102 above, the maximum slip ratio of the vehicle is determined based on the vehicle's reference speed and the wheel speeds of each wheel. The reference speed is an estimated value of the vehicle's longitudinal speed. Specifically, this includes the following steps S1021-S1022: S1021: The maximum wheel speed is the maximum wheel speed among all the wheel speeds in the vehicle.

[0053] Specifically, this can be achieved by acquiring the wheel speeds of each of the four wheels in real time while the vehicle is in a steady-state parking position. For a four-wheeled vehicle, the wheel speeds of the left front wheel, right front wheel, left rear wheel, and right rear wheel are acquired separately. These wheel speed values ​​are compared, and the maximum value is selected as the maximum wheel speed at the current moment, i.e., the maximum wheel speed that satisfies the relational expression. ,in, The left front wheel, The right front wheel, It is the left rear wheel. It is the right rear wheel.

[0054] The reason for selecting the maximum wheel speed is that when a vehicle is parked on a slope on a road surface with a low coefficient of friction, the wheel that first exceeds the friction limit and begins to slip will have its speed increase sharply. The wheel speed of this wheel will become the maximum value among the four wheels. Therefore, using the maximum wheel speed as the basis for subsequent calculation of the maximum slip ratio can most sensitively detect the occurrence of wheel slip.

[0055] S1022: The maximum slip ratio is obtained based on the maximum wheel speed and the reference vehicle speed.

[0056] Specifically, after obtaining the maximum wheel speed, the maximum slip ratio of the vehicle can be calculated based on the following formula 1, in conjunction with the reference vehicle speed:

[0057] In the formula, For the maximum slip ratio, For maximum wheel speed, For reference speed.

[0058] The reference speed is an estimated value used by the vehicle control system to characterize the longitudinal motion speed of the vehicle body, calculated in real time based on wheel speed signals and vehicle acceleration signals. In steady-state parking on a slope, the control target for the reference speed is 0 km / h, meaning the vehicle control system strives to keep the vehicle body stationary through closed-loop regulation.

[0059] When all wheels are not slipping, the wheel speeds are basically the same as the reference vehicle speed, with the maximum wheel speed close to 0. At this point, the calculated maximum slip ratio λ is close to 0. When a drive wheel exceeds its traction limit and begins to slip, its wheel speed rises rapidly, causing the maximum wheel speed to be significantly greater than the reference vehicle speed. In this case, the calculated maximum slip ratio is a large positive value. That is, the magnitude of the maximum slip ratio directly reflects the severity of wheel slippage; the larger the maximum slip ratio, the more severe the wheel spinning, and the higher the risk of the vehicle losing traction and rolling backwards. Therefore, this method can achieve quantitative monitoring of wheel slippage status by calculating the maximum slip ratio in real time.

[0060] In step S103 above, if wheel slippage occurs, updated drive torque and updated braking torque are obtained based on the maximum slip ratio, basic drive torque, and basic braking torque. Specifically, this includes the following steps S1031-S1032: S1031: If wheel slippage occurs in the vehicle, the drive torque correction coefficient is determined based on the maximum slip ratio. The drive torque correction coefficient is a value between (0,1).

[0061] Specifically, after obtaining the maximum slip ratio, it is necessary to determine whether wheel slippage has occurred. This determination is based on comparing the maximum slip ratio with a preset slip threshold. If the maximum slip ratio is greater than the preset slip threshold, wheel slippage is determined, and torque correction is required. If the maximum slip ratio is less than or equal to the preset slip threshold, wheel slippage is considered to have not occurred, and control continues according to the basic drive torque and basic braking torque. The preset slip threshold can be calibrated according to different vehicle models and road conditions, and can be set to 15% or 30% for example.

[0062] When wheel slippage is detected, it indicates that the current base drive torque has exceeded the adhesion limit provided by the sloped road surface, and the base drive torque needs to be attenuated. The degree of attenuation is determined by a drive torque correction factor, which is a value between 0 and 1.

[0063] The method for determining the drive torque correction coefficient is to obtain the maximum slip ratio-drive torque correction coefficient table calibrated for the vehicle, and then look up the corresponding drive torque correction coefficient in the maximum slip ratio-drive torque correction coefficient table based on the maximum slip ratio.

[0064] Different vehicle models should correspond to different maximum slip ratio-drive torque correction coefficient tables. In one specific embodiment, a maximum slip ratio-drive torque correction coefficient table is shown in Table 2 below.

[0065] Table 2 Maximum Slip Ratio - Drive Torque Correction Coefficient Table

[0066] As shown in Table 2 above, a higher maximum slip ratio indicates more severe wheel slippage, requiring more drive torque attenuation and a smaller drive torque correction coefficient. In the example shown in Table 2, the preset slip threshold is 30%. When the maximum slip ratio is below 30%, wheel slippage can be considered to have not yet occurred, and the drive torque correction coefficient is set to 1, meaning no drive torque attenuation is performed temporarily. As the maximum slip ratio increases, the drive torque correction coefficient gradually decreases. When the maximum slip ratio exceeds 90%, the correction coefficient can be reduced to 0.3, resulting in a significant attenuation of drive torque.

[0067] S1032: Based on the drive torque correction coefficient, the base drive torque, and the base braking torque, obtain the updated drive torque and the updated braking torque. This specifically includes the following steps S10321-S10323: S10321: Determine the updated drive torque based on the drive torque correction coefficient and the base drive torque.

[0068] Specifically, after obtaining the drive torque correction coefficient, the base drive torque can be attenuated based on the drive torque correction coefficient to obtain the updated drive torque. The calculation formula is as follows:

[0069] In the formula, To update the drive torque, Based on the driving torque, This is the driving torque correction factor.

[0070] Since the driving torque correction factor ranges from (0,1), the calculated updated driving torque is less than the base driving torque, meaning the driving torque has been attenuated. The degree of attenuation is determined by the magnitude of the driving torque correction factor; the higher the maximum slip ratio and the smaller the driving torque correction factor, the smaller the attenuated updated driving torque will be.

[0071] In this way, the method can reduce the output torque of the drive motor in time when the wheel slips, so as to suppress the tendency of the wheel to continue spinning and give the wheel a chance to regain road adhesion.

[0072] S10322: Determine the torque correction value based on the updated drive torque and the base drive torque.

[0073] Specifically, after obtaining the updated drive torque, the reduction in drive torque, i.e., the torque correction value, can be further calculated. The torque correction value represents the amount of torque attenuation from the base drive torque to the updated drive torque, and the calculation formula is as follows:

[0074] In the formula, This is the torque correction value. Based on the driving torque, This is the driving torque correction factor.

[0075] This torque correction value is the amount of torque subtracted from the drive motor. This torque was originally provided by the drive motor to maintain parking on the slope, but now it needs to be removed due to wheel slippage. In order to ensure that the vehicle can still maintain the total parking torque and prevent the vehicle from rolling downhill due to the reduction in the total parking torque, this reduced drive torque needs to be made up by increasing the braking torque.

[0076] S10323: Determine the updated braking torque based on the torque correction value and the base braking torque.

[0077] Specifically, the torque correction value for the decrease in driving torque needs to be supplemented by increasing the braking torque, that is, the amount of correction for the increase in braking torque should be equal to the amount of correction for the decrease in driving torque.

[0078] Based on the torque correction value and the base braking torque, the updated braking torque is calculated using the following formula 4:

[0079] In the formula, To update the braking torque, Based on the braking torque, This is the torque correction value. Based on the driving torque, This is the driving torque correction factor.

[0080] Based on the above calculations, the updated braking torque is increased compared to the base braking torque, and the increase is equal to the decrease in driving torque. This achieves the goal of transferring a portion of the driving torque to braking torque while maintaining the total parking torque, thus suppressing wheel spin and preserving hill-climbing ability.

[0081] In this embodiment of the application, after completing the above step S103 and obtaining the updated driving torque and the updated braking torque, the application further includes step S1033: if the updated braking torque is greater than the vehicle's maximum braking torque, then the maximum braking torque is used as the updated braking torque.

[0082] Specifically, in actual control, the maximum braking torque that the braking control system can provide is limited, constrained by factors such as the hardware capabilities of the braking control system, hydraulic pressure, and temperature. The calculated updated braking torque may exceed the maximum braking torque that the braking control system can provide. When this occurs, the braking control system cannot fully respond to the request for updated braking torque and sets the updated braking torque to the maximum braking torque of the braking control system. In this case, because the updated braking torque cannot fully compensate for the attenuation of the drive torque, the total parking torque cannot be fully satisfied, and the vehicle may experience a slow roll. However, compared to the risk of rapid roll and lateral deviation that may be caused by wheel spin, this controlled slow roll is safer, and the attenuation of the drive torque can effectively suppress the wheel spin, allowing the wheels to attempt to regain ground traction and avoiding serious loss of control such as rapid roll and lateral deviation due to the wheels completely losing traction.

[0083] In step S104 above, the driving torque of the vehicle is updated to the driving torque and the braking torque is updated to the braking torque.

[0084] Specifically, after determining the updated drive torque and updated braking torque, the vehicle can be controlled according to the updated results. A drive torque request command is sent to the motor controller, requesting the drive motor to output a drive torque equal to the updated drive torque; simultaneously, a braking torque request command is sent to the braking control system, requesting the braking control system to output a braking torque equal to the updated braking torque.

[0085] The combined action of driving torque and braking torque provides the vehicle with total parking torque, enabling the vehicle to maintain a steady stop on the slope. At this point, because the driving torque has been attenuated according to the maximum slip ratio, the tendency of the wheels to spin is effectively suppressed, allowing the drive wheels to regain or maintain road surface traction. Simultaneously, the braking torque increases accordingly to compensate for the portion lost due to the attenuation of driving torque, ensuring that the vehicle does not roll away due to insufficient total parking torque.

[0086] During the control process, the actual driving torque fed back by the motor controller and the actual braking torque fed back by the braking control system are received in real time to form a closed-loop control, so as to ensure that the actual execution result is consistent with the updated request command.

[0087] To enable those skilled in the art to further understand this solution, a specific embodiment is provided below, illustrating the method more clearly with reference to a vehicle control module comprising a vehicle control unit (VCU), a motor control unit (MCU), and an integrated brake control system (IBC): (Refer to...) Figure 2As shown, the vehicle controller, as the core control unit, interacts with the braking control system and the motor controller. Specifically, the vehicle controller sends a braking torque control request to the braking control system, while simultaneously receiving feedback from the braking control system regarding the actual braking torque, wheel speeds of each wheel, and a reference vehicle speed. The vehicle controller also sends a drive torque control request to the motor controller, while receiving feedback from the motor controller regarding the actual drive torque. During the control process, the vehicle controller first calculates the vehicle's maximum slip ratio based on the received wheel speeds and reference vehicle speed. Then, based on this maximum slip ratio, it corrects the base drive torque and base braking torque to calculate updated drive torque and updated braking torque. Finally, based on the updated drive torque and updated braking torque, it sends the corresponding drive torque request and braking torque request to the motor controller and braking control system for execution, respectively, thereby achieving anti-slip control during vehicle parking on slopes. Through this interaction process, the vehicle controller can monitor wheel status in real time and dynamically adjust torque distribution, effectively suppressing wheel spin and preventing vehicle rollback.

[0088] Example 2 Based on the same inventive concept, embodiments of the present invention also provide a vehicle parking slope anti-skid control device, referring to... Figure 3 As shown, the device includes: The first determining module 101 is used to determine the basic driving torque and basic braking torque of the vehicle when it is in a steady-state hill-climbing state. The second determining module 102 is used to determine the maximum slip ratio of the vehicle based on the reference vehicle speed and the wheel speed of each wheel; wherein the reference vehicle speed is an estimated value used to characterize the longitudinal movement speed of the vehicle. The update module 103 is used to obtain an updated drive torque and an updated braking torque based on the maximum slip ratio, the basic drive torque, and the basic braking torque when the vehicle experiences wheel slippage. The control module 104 is used to control the driving torque of the vehicle to be the updated driving torque and the braking torque to be the updated braking torque.

[0089] Example 3 Based on the same inventive concept, embodiments of the present invention also provide a computer-readable storage medium storing a computer program / instruction thereon, which, when executed by a processor, implements the vehicle parking slope anti-skid control method as described in Embodiment 1 above.

[0090] Example 4 Based on the same inventive concept, this embodiment of the invention also provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the vehicle parking slope anti-skid control method as described in Embodiment 1 above.

[0091] Example 5 Based on the same inventive concept, this embodiment of the invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory. When the processor executes the computer program, it implements the vehicle parking slope anti-skid control method as described in Embodiment 1 above.

[0092] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0093] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0094] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0095] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0096] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for controlling vehicle anti-skid on a slope, characterized in that, The method includes: Determine the basic driving torque and basic braking torque of the vehicle when it is in a steady-state parking position on a slope; The maximum slip ratio of the vehicle is determined based on the reference vehicle speed and the wheel speed of each wheel; wherein the reference vehicle speed is an estimated value of the longitudinal speed of the vehicle. If the vehicle experiences wheel slippage, then based on the maximum slip ratio, the basic drive torque, and the basic braking torque, updated drive torque and updated braking torque are obtained. The driving torque of the vehicle is controlled to be the updated driving torque, and the braking torque is controlled to be the updated braking torque.

2. The method according to claim 1, characterized in that, If the vehicle experiences wheel slippage, then based on the maximum slip ratio, the basic drive torque, and the basic braking torque, updated drive torque and updated braking torque are obtained, including: If the vehicle experiences wheel slippage, a drive torque correction coefficient is determined based on the maximum slip ratio; wherein the drive torque correction coefficient is a value between (0,1); Based on the drive torque correction coefficient, the base drive torque, and the base braking torque, the updated drive torque and the updated braking torque are obtained.

3. The method according to claim 2, characterized in that, The process of obtaining the updated drive torque and updated braking torque based on the drive torque correction coefficient, the base drive torque, and the base braking torque includes: The updated drive torque is determined based on the drive torque correction coefficient and the base drive torque; Based on the updated drive torque and the base drive torque, a torque correction value is determined; The updated braking torque is determined based on the torque correction value and the base braking torque.

4. The method according to claim 1, characterized in that, Determining the maximum slip ratio of the vehicle based on its reference vehicle speed and the wheel speeds of each wheel includes: The maximum wheel speed is defined as the maximum wheel speed among all the wheel speeds in the vehicle. The maximum slip ratio is obtained based on the maximum wheel speed and the reference vehicle speed.

5. The method according to claim 1, characterized in that, After obtaining the updated drive torque and updated braking torque based on the maximum slip ratio, the base drive torque, and the base braking torque if wheel slip occurs in the vehicle, the method further includes: If the updated braking torque is greater than the vehicle's maximum braking torque, then the maximum braking torque is used as the updated braking torque.

6. The method according to claim 1, characterized in that, The vehicle is determined to be experiencing wheel slippage in the following manner: If the maximum slip ratio is greater than the preset slip threshold, then it is determined that the vehicle has wheel slippage.

7. The method according to claim 1, characterized in that, The determination of the basic driving torque and basic braking torque when the vehicle is steadily parking on a slope includes: If the vehicle needs to be in a steady-state parking position, determine the total parking torque required for the vehicle; The distribution ratios of driving torque and braking torque are determined based on the slope of the slope where the vehicle is located. The base drive torque and base braking torque are determined based on the distribution ratios of the total parking torque and the drive torque and braking torque, respectively.

8. The method according to claim 7, characterized in that, After determining the base drive torque and base braking torque based on the distribution ratios corresponding to the total parking torque, the drive torque, and the braking torque, the method further includes: The driving torque of the vehicle is controlled to be the basic driving torque, and the braking torque is controlled to be the basic braking torque.

9. The method according to claim 8, characterized in that, Also includes: If the vehicle's drive motor or braking system is limited, causing the drive torque to fail to reach the base drive torque or the braking torque to fail to reach the base braking torque, the base drive torque and the base braking torque are dynamically adjusted, ensuring that the sum of the adjusted base drive torque and the base braking torque is still equal to the total parking torque.

10. A vehicle parking slope anti-skid control device, characterized in that, include: The first determining module is used to determine the basic driving torque and basic braking torque of the vehicle when it is steadily parking on a slope. The second determining module is used to determine the maximum slip ratio of the vehicle based on the reference vehicle speed and the wheel speed of each wheel; wherein the reference vehicle speed is an estimated value of the longitudinal movement speed of the vehicle. An update module is used to obtain an updated drive torque and an updated braking torque based on the maximum slip ratio, the basic drive torque, and the basic braking torque if the vehicle experiences wheel slippage. The control module is used to control the vehicle's drive torque to the updated drive torque and braking torque to the updated braking torque.

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