Vehicle control method and device, vehicle and storage medium

Abstract

Embodiments of the present application provide a vehicle control method and device, a vehicle and a storage medium. The method is applied to a vehicle, the vehicle adopts distributed driving, and the method comprises: in the case of monitoring that the vehicle travels on a split road surface, acquiring a working parameter of the vehicle; determining a maximum torque difference based on the working parameter of the vehicle; reducing the torque of a first wheel in a coaxial wheel, and controlling the working of the first wheel according to the reduced torque of the first wheel. In the technical solution provided in the embodiments of the present application, in the case of monitoring that the vehicle travels on a specified road surface, the vehicle determines the maximum torque difference between the torque of the high adhesion side wheel and the torque of the low adhesion side wheel based on the working parameter, and controls the torque of the high adhesion side wheel according to the maximum torque difference, which can reduce the probability of vehicle instability caused by excessive yaw moment, and increase the driving safety of the vehicle.

Description

Technical Field

[0001] The present application relates to the field of automobile technology, and more specifically, to a vehicle control method, device, vehicle, and storage medium. Background Art

[0002] An open road is a road where the coaxial wheels of a vehicle have significantly different adhesion coefficients. When a vehicle travels on an open road, the torque on the wheel with lower adhesion is reduced, which generates a yaw moment and reduces vehicle stability.

[0003] In related technologies, when a vehicle is traveling on a road with two opposite sides, the low-addition side wheels will slip. At this time, the traction control system is activated to reduce the torque of the low-addition side wheels, while the torque of the high-addition side wheels remains unchanged. At this time, the vehicle generates a yaw moment, and the driver resists the yaw moment by correcting the steering wheel.

[0004] However, if the difference between the torque of the high-addition wheel and the torque of the low-addition wheel is too large, the steering wheel cannot resist the yaw moment even if it is corrected to the maximum angle, causing the vehicle to lose stability. Summary of the Invention

[0005] Embodiments of the present application provide a vehicle control method, device, vehicle, and storage medium.

[0006] In a first aspect, an embodiment of the present application provides a vehicle control method, which is applied to a vehicle, and the vehicle adopts distributed drive. The method includes: when monitoring that the vehicle is traveling on a double road, obtaining the operating parameters of the vehicle, the operating parameters of the vehicle are used to characterize at least one of the vehicle's speed information, the vehicle's force condition, and the vehicle's torque; determining the maximum torque difference based on the vehicle's operating parameters; reducing the torque of a first wheel among coaxial wheels, and controlling the operation of the first wheel according to the reduced torque of the first wheel; wherein the difference between the reduced torque of the first wheel and the torque of the first wheel among the coaxial wheels is less than or equal to the maximum torque difference, and the adhesion coefficient of the road surface on which the first wheel travels is greater than the adhesion coefficient of the road surface on which the second wheel travels.

[0007] In a second aspect, an embodiment of the present application provides a vehicle control device, the device comprising: a parameter acquisition module configured to acquire a working parameter of a vehicle when it is detected that the vehicle is running on a split road, the working parameter of the vehicle being used to represent at least one of speed information of the vehicle, a force condition of the vehicle, and a torque of the vehicle; a torque difference determination module configured to determine a maximum torque difference based on the working parameter of the vehicle; and a control module configured to reduce a torque of a first wheel in a coaxial wheel, and control the first wheel to work according to the reduced torque of the first wheel, wherein a difference between the reduced torque of the first wheel and the torque of the first wheel in the coaxial wheel is less than or equal to the maximum torque difference, and an adhesion coefficient of a road on which the first wheel runs is greater than an adhesion coefficient of a road on which a second wheel runs.

[0008] In a third aspect, an embodiment of the present application provides a vehicle, comprising a processor and a memory, the memory storing computer program instructions, and the computer program instructions are invoked by the processor to execute the vehicle control method according to the first aspect.

[0009] In a fourth aspect, an embodiment of the present application provides a computer readable storage medium, the computer readable storage medium storing program codes, and the program codes are invoked by a processor to execute the vehicle control method according to the first aspect.

[0010] In a fifth aspect, an embodiment of the present application provides a computer program product, when the product is executed, the vehicle control method according to the first aspect can be implemented.

[0011] The vehicle control method provided by the embodiments of the present application can determine the maximum difference between the torque of the high adhesion side wheel and the torque of the low adhesion side wheel based on the working parameter when it is detected that the vehicle is running on a specified road condition (the coaxial wheels run on a road with a high adhesion coefficient and a road with a low adhesion coefficient), and then control the difference between the torque of the high adhesion side wheel and the torque of the high adhesion side wheel to be always less than the maximum torque difference. Since the maximum torque difference is the maximum torque difference allowed to maintain the stability of the vehicle, controlling the torque of the high adhesion side wheel according to the maximum torque difference can reduce the probability of the vehicle losing stability due to the excessive yaw moment, and increase the driving safety of the vehicle. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0013] Figure 1 is a schematic diagram of a vehicle provided by the related art driving on a split road.

[0014] Figure 2 FIG. 1 is a schematic diagram of a vehicle driving on a split road according to the related art.

[0015] Figure 3 FIG. 2 is a schematic diagram of a vehicle according to an embodiment of the present application.

[0016] Figure 4 FIG. 3 is a schematic diagram of a motor torque control system according to an embodiment of the present application.

[0017] Figure 5 FIG. 4 is a flowchart of a vehicle control method according to an embodiment of the present application.

[0018] Figure 6 FIG. 5 is a flowchart of a vehicle control method according to another embodiment of the present application.

[0019] Figure 7 FIG. 6 is a block diagram of a vehicle control apparatus according to an embodiment of the present application.

[0020] Figure 8 FIG. 7 is a functional block diagram of a vehicle according to an embodiment of the present application.

[0021] Figure 9 FIG. 8 is a functional block diagram of a computer-readable storage medium according to an embodiment of the present application. DETAILED DESCRIPTION

[0022] The embodiments of the present application will be described in detail below with reference to the drawings, wherein the same or like components are denoted by the same or like reference numerals throughout the drawings, and repetitive descriptions on the same or like components will be omitted. The embodiments described below are merely exemplary for explaining the present application, and should not be construed as limiting the present application.

[0023] In order to make the technical personnel in the art better understand the scheme of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0024] The technical terms related to the embodiments of the present application will be introduced below.

[0025] Open road: a road surface with a large difference in the adhesion coefficient for the coaxial wheels of a vehicle. For example, the first wheel in the coaxial wheels travels on a dry asphalt road surface with an adhesion coefficient of x1, and the second wheel in the coaxial wheels travels on an icy road surface with an adhesion coefficient of x2. If the absolute value of the difference between x1 and x2 is greater than a pre-set adhesion coefficient threshold a, it indicates that the vehicle is currently traveling on an open road.

[0026] Adhesion coefficient: the ratio of the adhesion force to the normal force of the wheel, which can be approximately considered as the road surface friction coefficient. A road surface with a high adhesion coefficient (such as a gravel road or an asphalt road) is less likely to cause the vehicle to skid and is safe for driving. A road surface with a low adhesion coefficient (such as snow or ice) is more likely to cause the vehicle to skid and poses a greater safety hazard.

[0027] Torque: the moment of force that causes an object to rotate, which is equal to the product of the force and the force arm. The international unit is newton-meter (N·m).

[0028] The inventors have found through long-term research that, for a vehicle with distributed driving, when the vehicle is driving on an open road, the wheels driving on a low adhesion coefficient ground (hereinafter referred to as low adhesion side wheels) will lose traction due to skidding, while the wheels driving on a high adhesion coefficient ground (hereinafter referred to as high adhesion side wheels) will continue to drive forward according to the original torque. At this time, the vehicle is subjected to a yaw force, resulting in a yaw angular acceleration and a yaw angular velocity. At this time, it is more difficult for the driver to control the vehicle, resulting in an increased probability of a safety accident of the vehicle.

[0029] Reference Figure 1 , which shows a working schematic diagram of a vehicle provided by the related art. In this example, the vehicle 110 is a four-wheel drive vehicle, the wheels 111 and 112 travel on a high adhesion coefficient ground, and the wheels 113 and 114 travel on a low adhesion coefficient ground. At this time, the vehicle 110 will generate a yaw angular acceleration and a yaw angular velocity as shown in the figure, making it more difficult for the driver to control the vehicle 110.

[0030] In the related art, when the vehicle is driving on an open road, the driver corrects the steering wheel angle to resist the yaw torque generated due to the difference between the torque of the high adhesion side wheels and the torque of the low adhesion side wheels.

[0031] Reference Figure 2 , which shows a working schematic diagram of a vehicle provided by the related art. In this example, the vehicle 110 is a four-wheel drive vehicle, the wheels 111 and 112 travel on a high adhesion coefficient ground, and the wheels 113 and 114 travel on a low adhesion coefficient ground. At this time, the driver turns the steering wheel in the opposite direction of the yaw torque to resist the yaw torque.

[0032] However, when the difference between the torque of the high adhesion side wheel and the torque of the low adhesion side wheel is too large, the yaw moment is also large, even if the driver turns the steering wheel to the maximum angle, the yaw moment cannot be resisted, at this time, the vehicle loses stability, and the driving safety of the vehicle cannot be guaranteed.

[0033] Based on the problems in the related art, the embodiments of the present application provide a vehicle control method and device, a vehicle and a storage medium. When it is monitored that the vehicle is running on a specified road condition (the same shaft wheels run on a high adhesion coefficient road and a low adhesion coefficient road respectively), the vehicle determines the maximum difference between the torque of the high adhesion side wheel and the torque of the low adhesion side wheel based on working parameters, and then controls the difference between the torque of the high adhesion side wheel and the torque of the low adhesion side wheel to be always less than the maximum torque difference. Since the maximum torque difference is the maximum torque difference allowed to maintain the stability of the vehicle, controlling the torque of the high adhesion side wheel according to the maximum torque difference can reduce the probability of the vehicle losing stability due to the too large yaw moment, and increase the driving safety of the vehicle.

[0034] Please refer to Figure 3 which shows a schematic diagram of a vehicle 300 provided by an embodiment of the present application. The vehicle 300 is a distributed drive vehicle, and the vehicle 300 can be an electric vehicle.

[0035] In some embodiments, the vehicle 300 is a four-motor driven vehicle, that is, the four wheels of the vehicle 300 are respectively controlled by four motors. In other embodiments, the vehicle 300 is a three-motor driven vehicle, wherein the two wheels of the rear axle are controlled by different motors, and the two wheels of the front axle are controlled by the same motor.

[0036] The vehicle 300 includes a traction control system (Traction Control System, TCS), a motor torque control system (Motor Torque Control, MTC) and a vehicle control unit (Vehicle Control Unit, VCU).

[0037] The traction control system is used to enable the vehicle 300 to obtain the best traction in various driving conditions. In the embodiments of the present application, the traction control system is used to control the torque of the low adhesion side wheel to be reduced when the vehicle 300 runs on a split road. The vehicle control unit is used to control the vehicle to run according to various working parameters. In the embodiments of the present application, the vehicle control unit is used to control the torque of the high adhesion side wheel according to the maximum torque difference.

[0038] The following will be described in combination with Figure 4The motor torque control system 400 is described. The motor torque control system 400 comprises a vehicle state monitoring module 410, an opposite open road identification module 420, a yaw moment calculation module 430 and a torque control module 440.

[0039] The vehicle state monitoring module 410 is configured to monitor the state of the vehicle, including but not limited to the speed, acceleration, steering wheel angle of the vehicle, the wheel speed, moment of inertia, angular acceleration of each wheel of the vehicle, the angular acceleration, moment of inertia of each motor of the vehicle, etc. Optionally, the vehicle state monitoring module 410 is in communication with each sensor provided on the vehicle, receives sensor data sent by each sensor through the communication connection, and monitors the state of the vehicle through the sensor data. The communication connection can be an I2C bus connection.

[0040] The sensors provided on the vehicle include but are not limited to wheel speed sensors, acceleration sensors, motor torque sensors, brake torque sensors, gravity sensors, steering wheel angle sensors, yaw rate sensors, etc. Among them, the wheel speed sensor is used to obtain the wheel speed of each wheel of the vehicle, and the wheel speed sensor can be provided on the wheel shaft. The number of wheel speed sensors is determined according to the number of wheels, and the wheel speed sensor can be a Hall type wheel speed sensor or a magneto type wheel speed sensor. The acceleration sensor is used to monitor the acceleration of the vehicle, including but not limited to longitudinal acceleration and lateral acceleration. The motor torque sensor is used to monitor the motor torque, and the number of motor torque sensors can be determined according to the number of motors. The brake torque sensor is used to monitor the brake torque, which can be provided on the brake system of the vehicle. The gravity sensor is used to monitor the weight of the vehicle. The steering wheel angle sensor is used to monitor the steering wheel angle, and the yaw rate sensor is used to monitor the yaw rate of the vehicle.

[0041] The opposite open road identification module 420 is configured to determine whether the vehicle is running on the opposite open road based on the difference between the wheel speeds of the coaxial wheels of the vehicle. Optionally, the opposite open road identification module 420 determines that the vehicle is running on the opposite open road when it identifies that the difference between the wheel speeds of the coaxial wheels is greater than a first threshold. Further, the opposite open road identification module 420 is configured to determine whether the vehicle is running on the opposite open road based on the difference between the wheel speeds of the coaxial wheels of the vehicle and the difference between the driving forces of the coaxial wheels. Optionally, the opposite open road identification module 420 determines that the vehicle is running on the opposite open road when it identifies that the difference between the wheel speeds of the coaxial wheels is greater than a first threshold and the difference between the driving forces of the coaxial wheels is greater than a second threshold. Optionally, the opposite open road identification module sets the flag bit of the opposite open road to a preset value after determining that the vehicle is running on the opposite open road. The preset value is set according to experience, and in the embodiment of the present application, the preset value is 1.

[0042] The yaw moment calculation module 430 is configured to calculate a maximum yaw moment according to the left front wheel side force and the right front wheel side force. The torque control module 440 is configured to calculate a maximum torque difference based on the maximum yaw moment, the longitudinal vehicle speed, and the yaw angular velocity.

[0043] Referring to Figure 5 FIG. 1 shows a flowchart of a vehicle control method according to an embodiment of the present application. The method includes the following steps S501-S503.

[0044] In step S501, the working parameters of the vehicle are obtained when it is detected that the vehicle is running on a split road surface.

[0045] The working parameters of the vehicle are used to represent at least one of the speed information of the vehicle, the torque of the vehicle, and the force condition of the vehicle. The speed information of the vehicle includes, but is not limited to, the wheel speed of each wheel of the vehicle, the running speed of the vehicle, the longitudinal acceleration of the vehicle, the lateral acceleration of the vehicle, the yaw angular velocity of the vehicle, and the like.

[0046] The wheel speed of the wheel refers to the rotational speed of the wheel, which can be measured by a wheel speed sensor. The longitudinal acceleration of the vehicle refers to the acceleration consistent with the running direction of the vehicle, which can be measured by an acceleration sensor. The lateral acceleration of the vehicle refers to the acceleration perpendicular to the running direction of the vehicle, which can also be measured by an acceleration sensor. The sensor for measuring the lateral acceleration and the longitudinal acceleration can be the same acceleration sensor or different acceleration sensors.

[0047] The torque information of the vehicle includes at least one of the torque of each motor of the vehicle, the braking torque, and the like.

[0048] The split road surface refers to a road surface with an absolute value of the difference between the adhesion coefficients of the coaxial wheels greater than a first threshold value.

[0049] The first threshold value is set according to experiments or experience, which is not limited in the embodiments of the present application. For example, the first threshold value is 0.5. In a specific example, the first adhesion coefficient is 0.1, the second adhesion coefficient is 0.7, and the absolute value of the difference between them is 0.6, which is greater than the first threshold value, indicating that the vehicle is currently running on a split road surface.

[0050] In step S502, the maximum torque difference is determined based on the working parameters of the vehicle.

[0051] The maximum torque difference refers to the upper limit of the torque difference of the coaxial wheels under the premise of maintaining the stability of the vehicle. Specifically, when the torque of the low adhesion side wheel is 50 N.m, the maximum torque difference is 100 N.m, and the maximum torque of the high adhesion side wheel is 150 N.m.

[0052] In the embodiment of the present application, in the case that the vehicle is running on a split road surface, the maximum torque difference of the coaxial wheels satisfying the stability of the vehicle is determined based on the working parameter of the vehicle, and then the torque of the high-attached side wheel and the torque of the low-attached side wheel are controlled to be less than the maximum torque difference, so that the yaw moment of the vehicle can be maintained at a low level, the driver is easier to control the vehicle, the probability of the vehicle losing stability due to the excessive yaw moment is reduced, and the driving safety of the vehicle is improved.

[0053] In some embodiments, the working parameter of the vehicle includes a maximum lateral force, and step 502 includes the following sub-steps S502a-S502c.

[0054] In step 502a, the maximum yaw moment is determined based on the maximum lateral force.

[0055] The lateral force refers to the force perpendicular to the main axis at the point of action of the axial force. In the embodiment of the present application, the maximum lateral force can be the lateral force of the left front wheel or the lateral force of the right front wheel.

[0056] In some embodiments, the maximum lateral force is the product of the adhesion coefficient and the gravity of the vehicle.

[0057] The adhesion coefficient refers to the ratio of the adhesion force to the normal pressure (the direction perpendicular to the road surface) of the wheel, which can be approximately regarded as the static friction coefficient between the wheel and the road surface. There is a preset mapping relationship between the adhesion coefficient and the slip ratio, which can be represented by a curve. Therefore, the vehicle can first determine the slip ratio, and then determine the adhesion coefficient based on the preset mapping relationship.

[0058] wherein the slip ratio can be calculated in the following two ways: in some embodiments, a wheel speed sensor is arranged on the wheel of the vehicle to detect the wheel speed, and after the vehicle obtains the wheel speed and the vehicle speed, the slip ratio of the wheel is calculated by the following calculation formula.

[0059]

[0060] wherein u represents the vehicle speed, u w represents the wheel speed, w represents the angular velocity of the wheel, and s represents the slip ratio.

[0061] In other embodiments, an angular velocity sensor is arranged on the wheel of the vehicle to detect the angular velocity of the wheel, and after the vehicle obtains the angular velocity of the wheel and the vehicle speed, the slip ratio of the wheel is calculated by the following calculation formula.

[0062]

[0063] wherein u represents the vehicle speed, w represents the angular velocity of the wheel, r represents the radius of the wheel, and s represents the slip ratio.

[0064] The gravity of the vehicle refers to the product of the mass of the vehicle and the gravitational acceleration.

[0065] The maximum lateral force can be calculated by the following mathematical formula: Fy=Mu x Mg.

[0066] Wherein, Mu refers to the adhesion coefficient, and Mg refers to the gravity of the vehicle.

[0067] In some embodiments, the vehicle determines the product of the maximum lateral force and the target distance as the maximum yaw moment. The target distance refers to the distance from the center of mass to the center of the front wheel. The maximum yaw moment can be calculated by the following mathematical formula: Mz=Fy x a. Wherein, Mz refers to the maximum yaw moment, and a refers to the target distance.

[0068] Step S502b, based on the maximum yaw moment, the longitudinal vehicle speed and the yaw angular velocity, determining the maximum driving force difference.

[0069] The vehicle first calculates the initial driving force difference based on the maximum yaw moment, and then determines the product of the driving force difference, the longitudinal vehicle speed and the yaw angular velocity as the maximum driving force difference.

[0070] In some embodiments, the vehicle takes the result of dividing the maximum yaw moment by the wheel track as the initial driving force difference. The calculation result of the initial driving force difference Fraw can be calculated by the following mathematical formula: Fraw=Mz ÷ b. Wherein, b is the wheel track.

[0071] Step S502c, determining the maximum torque difference based on the maximum driving force difference.

[0072] The vehicle determines the product of the maximum driving force difference and the wheel radius as the maximum torque difference.

[0073] Step S503, reducing the torque of the first wheel in the coaxial wheels, and controlling the first wheel to work according to the reduced torque of the first wheel.

[0074] The difference between the reduced torque of the first wheel and the torque of the second wheel in the coaxial wheels is less than or equal to the maximum torque difference. The adhesion coefficient of the road surface on which the first wheel travels is greater than the adhesion coefficient of the road surface on which the second wheel travels, that is, the road surface on which the first wheel travels is a high adhesion side road surface, and the road surface on which the second wheel travels is a low adhesion side road surface. Alternatively, the road surface on which the first wheel travels is a dry asphalt road surface, and the road surface on which the second wheel travels is an ice surface.

[0075] In the above manner, the yaw moment of the vehicle can be maintained at a lower level, so that the driver is easier to control the vehicle, the probability of the vehicle losing stability due to the yaw moment being too large is reduced, and the driving safety of the vehicle is increased.

[0076] In summary, the technical scheme provided by the embodiments of the present application, by monitoring the vehicle driving on the specified road conditions (coaxial wheels driving on the high adhesion coefficient road surface and low adhesion coefficient road surface), the vehicle determines the maximum difference between the torque of the high adhesion side wheel and the torque of the low adhesion side wheel based on the working parameters, and then controls the difference between the torque of the high adhesion side wheel and the torque of the high adhesion side wheel to be always less than the maximum torque difference. Since the maximum torque difference is the maximum torque difference allowed to maintain the stability of the vehicle, controlling the torque of the high adhesion side wheel according to the maximum torque difference can reduce the probability of the vehicle losing stability due to excessive yaw moment, and increase the driving safety of the vehicle.

[0077] Please refer to Figure 6 which shows a flowchart of the vehicle control method provided by an embodiment of the present application. The method comprises the following steps S601-S604.

[0078] Step S601, in the case of monitoring the vehicle driving on the split road surface, if the working signal of the traction control module is received, the expected steering wheel angle is obtained according to the working signal.

[0079] The working signal of the traction control module is used to indicate that the traction control system is in the working state, at this time the torque of the first wheel is reduced. The expected steering wheel angle refers to the steering wheel angle required to maintain the stability of the vehicle. In some embodiments, the vehicle obtains the current yaw moment, and then determines the steering wheel angle required to resist the current yaw moment as the expected steering wheel angle.

[0080] The vehicle can determine the steering wheel angle required to resist the current yaw moment according to the mapping relationship between the yaw moment and the steering wheel angle. The above-mentioned mapping relationship can be a curve set according to experiments or experience, or a function relationship formula fitting the curve.

[0081] Step S602, in the case of the expected steering wheel angle being greater than the second threshold value, the working parameters of the vehicle are obtained.

[0082] The second threshold value is set according to the actual demand. Optionally, the second threshold value is dynamically set according to the maximum steering angle of the steering wheel. The second threshold value is less than the maximum steering angle of the steering wheel. In a specific example, the maximum steering angle of the steering wheel is 100 degrees, and the second threshold value is 50 degrees.

[0083] In the embodiment of the present application, after the traction control system controls the torque reduction of the low adhesion side wheel, it is first determined whether the steering wheel angle required to resist the current yaw moment is less than a preset second threshold value. If it is less than or equal to the second threshold value, it indicates that the driver can resist the current yaw moment by turning the steering wheel, and the vehicle does not perform the subsequent torque control step for the high adhesion side wheel. If it is greater than the second threshold value, it indicates that the driver cannot resist the current yaw moment by turning the steering wheel, and the vehicle performs the subsequent torque control step for the high adhesion side wheel.

[0084] In the above manner, on the one hand, the power consumption of the torque control system can be saved, and on the other hand, unnecessary torque control can be avoided in the case where the driver resists the yaw moment by turning the steering wheel.

[0085] In step S603, the maximum torque difference is determined based on the working parameters of the vehicle.

[0086] In step S604, the torque of the first wheel in the coaxial wheel is reduced, and the first wheel is controlled to work according to the reduced torque of the first wheel.

[0087] The difference between the reduced torque of the first wheel and the torque of the first wheel in the coaxial wheel is less than or equal to the maximum torque difference, and the adhesion coefficient of the road surface on which the first wheel travels is greater than the adhesion coefficient of the road surface on which the second wheel travels.

[0088] In other embodiments, the vehicle can also monitor the case where the vehicle travels on a split road surface. If the working signal of the traction control module is received, the subsequent torque control step for the high adhesion side wheel is performed according to the working signal. If the working signal of the traction control system is not received, the subsequent torque control step for the high adhesion side wheel is not performed.

[0089] The vehicle receives the working signal of the traction control system, which indicates that the torque of the low adhesion side wheel is reduced, and the torque control step for the high adhesion side wheel is performed, which can make the control timing more accurate and avoid the case where the torque control step is performed unnecessarily, thereby saving the power consumption of the torque control system.

[0090] In summary, the technical scheme provided by the embodiment of the present application can avoid the case where the torque control step is performed unnecessarily and save the power consumption of the torque control system by performing the subsequent torque control step for the high adhesion side wheel when the vehicle receives the working signal of the traction control system.

[0091] Furthermore, after the traction control system controls the torque reduction of the low-addition wheel, it is first checked whether the steering wheel angle required to resist the current yaw moment is less than a second threshold value. If the steering wheel angle is less than or equal to the second threshold value, the subsequent torque control step for the high-addition wheel is not performed. If the steering wheel angle is greater than the second threshold value, the subsequent torque control step for the high-addition wheel is performed. This can save power consumption of the torque control system on the one hand, and avoid unnecessary torque control when the driver can resist the yaw moment by the steering wheel angle on the other hand.

[0092] The present embodiment provides a torque control solution for high-addition wheels when a vehicle is traveling on an open road. To improve control accuracy, it is necessary to ensure that the vehicle is traveling on the open road. The following describes an implementation method for monitoring whether a vehicle is traveling on an open road.

[0093] In some embodiments, the vehicle monitors whether it is traveling on an oncoming road by the following steps: obtaining the wheel speeds corresponding to the coaxial wheels respectively, the coaxial wheels being controlled by different motors, and the wheel speeds corresponding to the coaxial wheels respectively including a first wheel speed and a second wheel speed; when the absolute value of the difference between the first wheel speed and the second wheel speed is greater than a first threshold, it is determined that the vehicle is traveling on an oncoming road.

[0094] Wheel speed refers to the rotational speed of the wheel, which can be measured by a wheel speed sensor. The first threshold can be set based on experiments or experience, and is not limited in this embodiment of the present application.

[0095] In some embodiments, when the absolute value of the difference between the first wheel speed and the second wheel speed is greater than a first threshold, it is determined that the vehicle is traveling on an opposite road. It can also be alternatively implemented as follows: when the absolute value of the difference between the first wheel speed and the second wheel speed is greater than the first threshold, the driving forces corresponding to the coaxial wheels are obtained, and the driving forces corresponding to the coaxial wheels include a first driving force and a second driving force; when the absolute value of the difference between the first driving force and the second driving force is greater than a second threshold, it is determined that the vehicle is traveling on an opposite road.

[0096] The second threshold is set based on experiments or experience, and is not limited in the present embodiment. When it is determined that the wheel speed difference of the coaxial wheels is large, further judgment is made based on the driving force difference of the coaxial wheels, so that the judgment of the specified road condition is more accurate.

[0097] It should be noted that after determining that the vehicle is on a divided road through the difference in wheel speeds of the coaxial wheels, if the first wheel speed is greater than the second wheel speed, the wheel with the first wheel speed is the second wheel, and the wheel with the second wheel speed is the first wheel; if the first wheel speed is less than the second wheel speed, the wheel with the first wheel speed is the first wheel, and the wheel with the second wheel speed is the second wheel.

[0098] The vehicle can also determine whether the vehicle is running on the split road surface through at least one of a slip rate difference of the coaxial wheels, a difference in adhesion coefficients of road surfaces on which the coaxial wheels run respectively, and a driving force difference of the coaxial wheels, and the embodiments of the present application are not limited in this regard.

[0099] Please refer to Figure 7 which shows a functional block diagram of a vehicle control device 700 provided by an embodiment of the present application. The device is applied to a vehicle, and the vehicle adopts distributed driving. The vehicle control device 700 comprises a parameter acquisition module 710, a torque difference determination module 720, and a control module 730.

[0100] The parameter acquisition module 710 is configured to acquire working parameters of the vehicle when it is monitored that the vehicle is running on the split road surface. The working parameters of the vehicle are used to represent at least one of speed information of the vehicle and force conditions of the vehicle. The torque difference determination module 720 is configured to determine a maximum torque difference based on the working parameters of the vehicle. The control module 730 is configured to reduce the torque of a first wheel in the coaxial wheels, and control the first wheel to work according to the reduced torque of the first wheel. The difference between the reduced torque of the first wheel and the torque of the first wheel in the coaxial wheels is less than or equal to the maximum torque difference, and the adhesion coefficient of the road surface on which the first wheel runs is greater than the adhesion coefficient of the road surface on which a second wheel runs.

[0101] To sum up, the technical scheme provided by the embodiments of the present application determines the maximum difference between the torque of the high adhesion side wheel and the torque of the low adhesion side wheel based on the working parameters of the vehicle when it is monitored that the vehicle is running on the specified road condition (the coaxial wheels run on the road surface with high adhesion coefficient and the road surface with low adhesion coefficient respectively), and then controls the difference between the torque of the high adhesion side wheel and the torque of the high adhesion side wheel to be always less than the maximum torque difference. Since the maximum torque difference is the maximum torque difference allowed to maintain the stability of the vehicle, the torque of the high adhesion side wheel is controlled according to the maximum torque difference, which can reduce the probability of the vehicle losing stability due to the excessive yaw moment, and increase the driving safety of the vehicle.

[0102] In some embodiments, the working parameters of the vehicle comprise a maximum lateral force, a longitudinal vehicle speed, and a yaw angular velocity. The torque difference determination module 720 is configured to determine a maximum yaw moment based on the maximum lateral force, determine a maximum driving force difference value based on the maximum yaw moment, the longitudinal vehicle speed, and the yaw angular velocity, and determine the maximum torque difference based on the maximum driving force difference value.

[0103] In some embodiments, the torque difference determination module 720 is configured to determine an intermediate driving force difference value based on the maximum yaw moment, and determine the maximum driving force difference value as the product of the intermediate driving force difference value, the longitudinal vehicle speed, and the yaw angular velocity.

[0104] In some embodiments, the device further includes a road condition monitoring module (not shown). The road condition monitoring module is configured to obtain wheel speeds corresponding to coaxial wheels, the coaxial wheels being controlled by different motors, the wheel speeds corresponding to the coaxial wheels including a first wheel speed and a second wheel speed; and determine that the vehicle is traveling on an opposite road if the absolute value of the difference between the first wheel speed and the second wheel speed is greater than a first threshold.

[0105] In some embodiments, the road condition monitoring module is specifically used to obtain the driving forces corresponding to the coaxial wheels respectively when the absolute value of the difference between the first wheel speed and the second wheel speed is greater than a first threshold, and the driving forces corresponding to the coaxial wheels respectively include a first driving force and a second driving force; when the absolute value of the difference between the first driving force and the second driving force is greater than a second threshold, it is determined that the vehicle is traveling on an opposite road.

[0106] In some embodiments, the parameter acquisition module 710 is configured to acquire the vehicle's operating parameters based on the operating signal received from the traction control module when the vehicle is detected traveling on an open road.

[0107] In some embodiments, the parameter acquisition module 710 is used to obtain an expected steering wheel angle based on the working signal received from the traction control module when the vehicle is detected traveling on a double-sided road. The expected steering wheel angle refers to the steering wheel angle required to keep the vehicle stable. When the expected steering wheel angle is greater than a second threshold, the vehicle's operating parameters are obtained.

[0108] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0109] In several embodiments provided in this application, the coupling between modules may be electrical, mechanical or other forms of coupling.

[0110] In addition, the functional modules in the various embodiments of the present application may be integrated into a processing module, or each module may exist physically separately, or two or more modules may be integrated into a single module. The above-mentioned integrated modules may be implemented in the form of hardware or software functional modules.

[0111] like Figure 8 As shown, the example of the present application further provides a vehicle 800, which includes a processor 810 and a memory 820. The memory 820 stores computer program instructions.

[0112] The processor 810 can include one or more processing cores. The processor 810 utilizes various interfaces and lines to connect various parts within the entire battery management system, to execute various functions of the battery management system and process data by running or executing instructions, programs, code sets or instruction sets stored in the memory 820, and calling data stored in the memory 820. Optionally, the processor 810 can be implemented in at least one of a hardware form of a digital signal processing (DSP), a field-programmable gate array (FPGA), and a programmable logic array (PLA). The processor 810 can be integrated with a combination of one or more of a central processing unit (CPU), a graphics processing unit (GPU), and a modem. Among them, the CPU is mainly used to process operating systems, user interfaces, and application programs; the GPU is used to render and draw display content; and the modem is used to process wireless communication. It can be understood that the above-mentioned modem can also not be integrated into the processor 810, but can be realized by a separate communication chip.

[0113] The memory 820 can include a random access memory (RAM) and can also include a read-only memory (ROM). The memory 820 can be used to store instructions, programs, codes, code sets or instruction sets. The memory 820 can include a program storage area and a data storage area, wherein the program storage area can store instructions for implementing an operating system, instructions for implementing at least one function (such as a touch function, a sound playing function, an image playing function, etc.), instructions for implementing various method examples described below, etc. The data storage area can also store data created by the vehicle in use (such as a phone book, audio and video data, chat record data, etc.).

[0114] Referring to Figure 9 It is shown that the embodiments of the present application further provide a computer readable storage medium 900, in which computer program instructions 910 are stored, and the computer program instructions 910 can be called by a processor to execute the methods described in the above embodiments.

[0115] The computer-readable storage medium 900 can be an electronic, magnetic, optical, or other physical storage device that stores executable computer program instructions. Examples of computer-readable storage media include, but are not limited to, a magnetic disk, a magnetic disk drive, a magnetic tape drive, an optical storage medium, a flash memory, a solid-state drive, a RAM, a ROM, and any combination of these or other computer-readable storage media. The computer-readable storage medium 900 can be non-transitory, in the sense that the computer-readable storage medium 900 does not have a signal per se (e.g., does not have a transitory signal per se). The computer-readable storage medium 900 can be non-transitory, in the sense that the computer-readable storage medium 900 does not have a signal per se (e.g., does not have a transitory signal per se). The computer-readable storage medium 900 has a storage space for storing computer program instructions 910 that perform any of the method steps described above. These computer program instructions 910 can be read or written from / to one or more computer program products. The computer program instructions 910 can be compressed in an appropriate form.

[0116] The above merely provides the preferred examples of the present application and does not limit the present application in any form. Although the present application has been disclosed as the above preferred examples, the present application is not intended to be limited to the above examples. Any person skilled in the art can make some changes or modifications to the above disclosed technical contents without departing from the scope of the present application, and any equivalent examples with equivalent changes or modifications made according to the technical essence of the present application to the above examples are still within the scope of the present application.

Claims

1. A vehicle control method characterized by, The method is applied to a vehicle with distributed driving, and the method comprises: In the case of monitoring that the vehicle travels on a split road surface, obtaining working parameters of the vehicle, the working parameters of the vehicle being used to represent at least one of speed information of the vehicle, force conditions of the vehicle, and torque of the vehicle; the working parameters of the vehicle comprising: maximum lateral force, longitudinal vehicle speed, and yaw angular velocity; determining a maximum yaw moment based on the maximum lateral force; determining a maximum driving force difference based on the maximum yaw moment, the longitudinal vehicle speed, and the yaw angular velocity; determining a maximum torque difference based on the maximum driving force difference; reducing the torque of a first wheel in a coaxial wheel, and controlling the first wheel to work according to the reduced torque of the first wheel; wherein the difference between the reduced torque of the first wheel and the torque of a second wheel in the coaxial wheel is less than or equal to the maximum torque difference, and the adhesion coefficient of the road surface on which the first wheel travels is greater than the adhesion coefficient of the road surface on which the second wheel travels.

2. The method of claim 1, wherein, The method further comprises: obtaining wheel speeds corresponding to the coaxial wheels respectively, the coaxial wheels being controlled by different motors, the wheel speeds corresponding to the coaxial wheels respectively comprising a first wheel speed and a second wheel speed; in the case that the absolute value of the difference between the first wheel speed and the second wheel speed is greater than a first threshold, determining that the vehicle travels on the split road surface.

3. The method of claim 1, wherein, The method further comprises: in the case that the absolute value of the difference between the first wheel speed and the second wheel speed is greater than a first threshold, obtaining driving forces corresponding to the coaxial wheels respectively, the driving forces corresponding to the coaxial wheels respectively comprising a first driving force and a second driving force; in the case that the absolute value of the difference between the first driving force and the second driving force is greater than a second threshold, determining that the vehicle travels on the split road surface.

4. The method of claim 3, wherein, The method further comprises: in the case of monitoring that the vehicle travels on the split road surface, if a working signal of a traction control module is received, obtaining the working parameters of the vehicle according to the working signal. The method further comprises:

5. The method according to any one of claims 1 to 4, characterized in that, in the case of monitoring that the vehicle travels on the split road surface, if a working signal of a traction control module is received, obtaining an expected steering wheel angle according to the working signal, the expected steering wheel angle being a steering wheel angle required for keeping the vehicle stable. ​ 6. The method of claim 5, wherein, ​ ​ In a case where the expected steering wheel angle is greater than a second threshold value, an operating parameter of the vehicle is acquired.

7. A vehicle control device characterized by comprising: The device comprises: An operating parameter acquisition module is configured to acquire an operating parameter of the vehicle in a case where it is monitored that the vehicle travels on a split road surface, the operating parameter of the vehicle being used to represent at least one of speed information of the vehicle, a force condition of the vehicle, and a torque of the vehicle, and the operating parameter of the vehicle comprising a maximum lateral force, a longitudinal vehicle speed, and a yaw angular speed. A torque difference determination module is configured to determine a maximum yaw torque based on the maximum lateral force, determine a maximum driving force difference value based on the maximum yaw torque, the longitudinal vehicle speed, and the yaw angular speed, and determine a maximum torque difference based on the maximum driving force difference value. A control module is configured to reduce a torque of a first wheel in a same axle as a second wheel, and control the first wheel to work according to the reduced torque of the first wheel, wherein a difference between the reduced torque of the first wheel and a torque of the second wheel is less than or equal to the maximum torque difference, and an adhesion coefficient of a road surface on which the first wheel travels is greater than an adhesion coefficient of a road surface on which the second wheel travels.

8. A vehicle characterized by comprising: The vehicle comprises a processor and a memory, the memory stores computer program instructions, and the computer program instructions are invoked by the processor to execute the vehicle control method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The computer readable storage medium stores program code, and the program code is invoked by the processor to execute the vehicle control method according to any one of claims 1-6.

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