Vehicle control method and device, vehicle, electronic equipment and storage medium

Abstract

The application discloses a vehicle control method and device, a vehicle, an electronic device and a storage medium. The vehicle control method comprises the following steps: determining a braking reference yaw angular velocity of a vehicle based on vehicle data; determining a working interval of driving brake control of the vehicle based on the braking reference yaw angular velocity; and performing collaborative control on driving and braking of the vehicle based on an actual yaw angular velocity of the vehicle and the working interval, so as to exert driving force or braking force on the same wheel.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and more particularly to a vehicle control method, device, vehicle, electronic device, and storage medium. Background Technology

[0002] With the development of science and technology and the rapid increase in the number of vehicles, enhancing the stability control of vehicle systems has become particularly important. Existing technologies are mainly based on traditional drive systems (such as engines, central motors, etc.) and wheel cylinder braking systems, achieving wheel-end torque vector control during wheel drive by superimposing the equal driving torque at the wheel end with the vector braking torque of the wheel cylinder.

[0003] Vehicles maintain stability through vector driving force or vector braking force on both sides of the wheel. When driving force and braking force exist on the same wheel at the same time, the driving and braking forces will conflict with each other, which will cause severe wear of the braking system and reduce the life of the brake, resulting in poor vehicle economy and stability. Summary of the Invention

[0004] In view of the above problems, this application provides a vehicle control method, device, vehicle, electronic device and storage medium, which can effectively solve the problem of severe brake wear caused by wheel-end torque-driven braking conflict in distributed drive vehicles, ensure vehicle stability and improve vehicle economy.

[0005] In a first aspect, this application provides a vehicle control method, which includes: determining a braking reference yaw rate of the vehicle based on vehicle data; determining a working range for driving and braking control of the vehicle based on the braking reference yaw rate; and coordinating driving and braking control of the vehicle based on the actual yaw rate and the working range, so as to apply driving force or braking force on the same wheel.

[0006] In the technical solution of this application embodiment, based on the operating characteristics of the drive and braking systems of a distributed drive vehicle, the vehicle's braking reference yaw rate is determined based on vehicle data, and the working range is confirmed accordingly. After confirming the specific working range, drive and braking are coordinated and controlled according to the actual yaw rate and the working range, ensuring that only driving force or braking force exists on the same wheel, effectively improving brake wear and enhancing vehicle stability and economy.

[0007] In some embodiments, the operating range includes a control range and a stable range; based on the vehicle's actual yaw rate and the operating range, the driving and braking of the vehicle are coordinated and controlled, including: determining the current range from the control range and the stable range based on the vehicle's actual yaw rate; when the current range is the control range, driving control of the wheels is performed; when the current range is the stable range, driving control or braking control of the wheels is performed.

[0008] In the technical solution of this application embodiment, yaw rate is an important parameter describing vehicle stability. The working range is divided into a maneuvering range and a stable range. The specific working range is determined based on the actual yaw rate of the vehicle, so that the wheels are driven or braked accordingly. This can avoid the simultaneous existence of driving and braking at the same wheel end. When the working range is the maneuvering range, driving control is performed to ensure that the vehicle speed does not decrease. When the working range is the stable range, driving or braking control is performed to avoid complex wheel forces and improve the handling and stability of the vehicle.

[0009] In some embodiments, when the current interval is a stable interval, driving control or braking control of the wheel is performed, including: when the current interval is a stable interval, determining the longitudinal force; and determining whether to drive control or brake control of the wheel based on the direction of the longitudinal force.

[0010] In some embodiments, determining the direction of the longitudinal force to drive or brake the wheel includes: driving the wheel when the direction of the longitudinal force is consistent with the direction of vehicle travel; and braking the wheel when the direction of the longitudinal force is consistent with the direction of vehicle travel.

[0011] In the technical solution of this application embodiment, when the current interval is in a stable interval, the wheels are controlled in a coordinated manner for driving and braking. It is determined whether the direction of the longitudinal force at the wheel end is consistent with the vehicle's driving direction, and corresponding driving or braking control is performed based on the determination result. When the direction of the longitudinal force is consistent with the vehicle's driving direction, driving control is performed; when the direction of the longitudinal force is opposite to the vehicle's driving direction, braking control is performed, ensuring that driving and braking do not coexist on the same wheel, thus achieving coordinated driving and braking control.

[0012] In some embodiments, when the current interval is the operating interval, driving control of the wheels includes: determining a first additional yaw moment based on the deviation between the actual yaw rate of the vehicle and a driving reference yaw rate, wherein the driving reference yaw rate is associated with stability factors, wheel longitudinal speed, wheel wheelbase, and front wheel steering angle; determining the driving torque of the wheels based on the first additional yaw moment; and driving control of the wheels based on the driving torque of the wheels to reduce the deviation between subsequent actual yaw rates and subsequent driving reference yaw rates.

[0013] In the technical solution of this application embodiment, the driving reference yaw rate is related to stability factors, wheel longitudinal speed, wheel wheelbase, and front wheel steering angle. When the current working range is in the operating range, in order to reduce the deviation between the actual yaw rate of the vehicle and the driving reference yaw rate in subsequent driving, a first additional yaw torque is determined based on the deviation between the current actual and reference yaw rates of the vehicle, thereby determining the driving torque of the wheel and driving the wheel to control the drive, which can ensure that the current vehicle speed does not decrease and achieve stable acceleration.

[0014] In some embodiments, when the current interval is a stable interval, determining the longitudinal force includes: determining a second additional yaw moment based on the deviation between the vehicle's actual yaw rate and a braking reference yaw rate; and determining the longitudinal force based on the second additional yaw moment so as to determine the wheel's drive torque or braking torque based on the longitudinal force; wherein, when the wheel is driven based on the wheel's drive torque, the deviation between the subsequent actual yaw rate and the subsequent drive reference yaw rate can be reduced, and when the wheel is braked based on the wheel's braking torque, the deviation between the subsequent actual yaw rate and the subsequent braking reference yaw rate can be reduced.

[0015] In the technical solution of this application embodiment, when the vehicle is in a stable range, a second additional yaw moment is determined based on the deviation between the actual yaw rate of the vehicle and the braking reference yaw rate, thereby determining the longitudinal force. Then, based on the driving torque or braking torque, the wheels are subjected to corresponding driving control or braking control to reduce the deviation between the subsequent actual yaw rate and the subsequent driving or braking reference yaw rate, thereby decelerating the vehicle and enabling stable control when the vehicle is in extreme instability.

[0016] In some embodiments, the braking reference yaw rate includes an upper limit value and a lower limit value of the yaw rate; determining the working range for driving braking control of the vehicle based on the braking reference yaw rate includes: determining an initial braking dead zone based on the upper limit value and the lower limit value of the yaw rate; and determining the working range based on the initial braking dead zone.

[0017] In the technical solution of this application embodiment, the initial braking dead zone is determined based on the upper limit value and the lower limit value of the yaw rate, thereby improving the accuracy of the initial braking dead zone and further accurately determining the working range.

[0018] In some embodiments, the braking reference yaw rate further includes a braking reference yaw rate offset; determining the working range based on the initial braking dead zone includes: increasing the initial braking dead zone based on the braking reference yaw rate offset to obtain a target braking dead zone; and determining the working range based on the target braking dead zone.

[0019] In the technical solution of this application embodiment, the initial braking dead zone is increased based on the braking reference yaw rate offset to obtain the target braking dead zone. The working range is determined based on the target braking dead zone, and drive-braking coordinated control is performed as much as possible while maintaining the original system.

[0020] In some embodiments, determining the operating range based on the target braking dead zone includes: defining the target braking dead zone as the operating range; and defining the area outside the target braking dead zone as the stable range.

[0021] In the technical solution of this application embodiment, the target braking dead zone is defined as the operating range, thereby increasing the braking dead zone and increasing the area of ​​action of the driving force. The area outside the braking dead zone is defined as the stable range, thereby reducing the area of ​​action of the braking force. The driving needs of the vehicle are prioritized to be met within a larger operating range, thereby maintaining stability without reducing the wheel speed through the driving force, improving the vehicle's handling. Driving and braking are coordinated in the stable range where the vehicle may be unstable, ensuring the stability of the vehicle.

[0022] In some embodiments, the initial braking dead zone includes an upper limit value and a lower limit value of yaw rate; based on the braking reference yaw rate offset, the initial braking dead zone is increased to obtain the target braking dead zone, including: correcting the upper limit value and the lower limit value of yaw rate based on the braking reference yaw rate offset; and obtaining the target braking dead zone based on the corrected upper limit value and the corrected lower limit value of yaw rate.

[0023] In the technical solution of this application embodiment, the upper limit value of yaw rate and the lower limit value of yaw rate are corrected based on the braking reference yaw rate offset, thereby increasing the braking dead zone, that is, increasing the control range, thereby increasing the area of ​​action of driving force and decreasing the area of ​​action of braking force. It can improve vehicle handling by controlling the driving force without reducing the wheel speed, while reducing the modification to the original system.

[0024] In some embodiments, determining the braking reference yaw rate offset based on vehicle data includes: determining a driving yaw moment limit based on vehicle data; determining a yaw rate limit based on the driving yaw moment limit using a two-degree-of-freedom model of the vehicle; and determining the braking reference yaw rate offset based on the yaw rate limit.

[0025] In the technical solution of this application embodiment, the driving yaw moment limit is determined according to vehicle data, and the maximum yaw rate is determined based on the two-degree-of-freedom model that describes the steady state of the vehicle from the perspective of kinematics and dynamics when the driving yaw moment is at its maximum value. This determines the braking reference yaw rate offset, so as to correct the upper and lower limits of the braking reference yaw rate, thereby increasing the braking dead zone (handling range) and improving the vehicle's handling with reduced modifications to the original system.

[0026] On the other hand, this application provides a vehicle control device, which includes: a first determining module for determining a braking reference yaw rate of the vehicle based on vehicle data; a second determining module for determining a working range for driving and braking control of the vehicle based on the braking reference yaw rate; and a cooperative control module for coordinating the driving and braking of the vehicle based on the actual yaw rate and the working range, so as to apply driving force or braking force on the same wheel.

[0027] On the other hand, this application provides a vehicle including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of the method of any of the above embodiments.

[0028] On the other hand, this application provides an electronic device including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method of any of the above embodiments.

[0029] On the other hand, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method of any of the above embodiments.

[0030] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0031] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0032] Figure 1 A schematic diagram of a vehicle handling limit extension method based on drive-brake coordinated control is shown.

[0033] Figure 2A schematic diagram of a vehicle vector drive is shown;

[0034] Figure 3 A schematic flowchart of a vehicle control method according to an embodiment of this application is shown;

[0035] Figure 4 A schematic diagram of the initial braking dead zone of an embodiment of this application is shown;

[0036] Figure 5 A schematic diagram of the target braking dead zone according to an embodiment of this application is shown;

[0037] Figure 6 A schematic diagram of the drive-brake coordinated control process according to an embodiment of this application is shown;

[0038] Figure 7 A block diagram of a vehicle control device according to an embodiment of this application is shown. Detailed Implementation

[0039] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0041] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0042] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0043] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0044] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0045] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0046] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0047] With the development of science and technology and the rapid increase in the number of vehicles, enhancing the stability control of vehicle systems has become particularly important. Existing technologies are mainly based on TVC (traditional drive system, such as engine, central motor, etc.) and VDC (wheel cylinder braking system). TVC is installed in VCU (vehicle control unit), and VDC is installed in BCU (brake control unit). Wheel-end torque vector control is achieved by superimposing the equal driving torque at the wheel end with the vector braking torque of the wheel cylinder.

[0048] Vehicles maintain stability through vector driving force or vector braking force on both sides of the wheel. When driving force and braking force exist on the same wheel at the same time, the driving and braking forces will conflict with each other, which will cause severe wear of the braking system and reduce the life of the brake, resulting in poor vehicle economy and stability.

[0049] Figure 1A schematic diagram of a vehicle handling limit extension method based on drive-brake coordinated control is shown.

[0050] like Figure 1 As shown, the method includes steps S110 to S150.

[0051] Step S110: Calculate the expected additional yaw moment based on the deviation between the current vehicle state and the expected vehicle state.

[0052] Step S120: Distribute the required longitudinal force to different wheels according to the additional yaw moment and the additional longitudinal force and their expected values.

[0053] Step S130: The longitudinal force required by the wheel is corrected by the wheel slip ratio.

[0054] Step S140: Based on the longitudinal force required by the modified wheel, coordinate the braking pressure of the braking system on the wheel with the engine output torque to generate a longitudinal force acting on the wheel.

[0055] This solution can only enable vehicles equipped with traditional drive systems to achieve different driving or braking forces on different wheels of the drive axle, making the longitudinal force of the vehicle controllable and adjusting the vehicle speed. However, it does not consider the integration strategy of the drive system and the wheel cylinder braking system of distributed drive vehicles. Moreover, the drive torque vector is achieved by superimposing the equal driving torque at the wheel end with the vector braking torque of the wheel cylinder, which causes problems such as severe brake wear, short braking system life, and poor vehicle economy.

[0056] Figure 2 A schematic diagram of a vehicle vector drive is shown.

[0057] like Figure 2 As shown, vehicles can achieve vehicle stability control through vector drive. When a vehicle enters stability control mode, it uses vector driving forces on both wheels to ensure stability, but it also uses vector braking forces on both wheels to ensure stability. When driving and braking forces exist simultaneously on the same wheel, the conflict between these forces can cause severe wear on the braking system and reduced brake life. Furthermore, the vehicle's driving force is not fully utilized to propel the vehicle forward, resulting in poor fuel economy. The simultaneous presence of driving and braking forces on the wheel creates complex forces, leading to decreased vehicle stability.

[0058] In view of this, this application proposes an optimized vehicle control method that can effectively solve the problem of severe brake wear caused by torque-driven braking conflict at the wheel ends in distributed drive vehicles, ensuring vehicle stability and improving vehicle economy.

[0059] This application provides a vehicle control method based on the actuation characteristics of the drive and braking systems of a distributed drive vehicle. The method determines the vehicle's braking reference yaw rate based on vehicle data and uses this to define the operating range. After defining the specific operating range, the drive and braking systems are coordinated and controlled according to the actual yaw rate and the operating range. This ensures that only driving force or braking force exists on the same wheel, effectively reducing brake wear and improving vehicle stability and fuel economy.

[0060] Taking a four-wheel independent drive system as an example, this application considers designing a drive-brake coordinated control strategy while minimizing modifications to the original drive and braking systems. This avoids the simultaneous existence of drive and brake at the wheel ends, so that the driving force is used as much as possible to propel the vehicle forward. This maximizes the characteristics of the braking system in ensuring vehicle stability and the drive system in improving vehicle handling. It can also be applied to distributed drive vehicles with two-wheel side electric mechanism type, three-electric mechanism type, and other drive types.

[0061] Figure 3 A flowchart of a vehicle control method according to an embodiment of this application is shown.

[0062] like Figure 3 As shown, the vehicle control method 300 provided in this application includes steps S310 to S330.

[0063] Step S310: Based on vehicle data, determine the vehicle's braking reference yaw rate.

[0064] For example, the braking reference yaw rate may include at least one of an upper limit yaw rate, a lower limit yaw rate, and a braking reference yaw rate offset. Vehicle data may include, for example, data related to the vehicle's motor capabilities, vehicle kinematic data, vehicle dynamics data, vehicle motion data, vehicle attribute data, etc., and the vehicle's braking reference yaw rate is calculated based on the vehicle data.

[0065] Step S320: Based on the braking reference yaw rate, determine the working range for driving braking control of the vehicle.

[0066] For example, the working range can be determined based on the braking reference yaw rate, and the working range can be divided into a working range for drive control or a working range for braking control.

[0067] Step S330: Based on the vehicle's actual yaw rate and operating range, coordinate the vehicle's driving and braking to apply driving or braking force to the same wheel.

[0068] For example, the working range is associated with the actual yaw rate during vehicle movement. For instance, the working range represents the association between the actual yaw rate and the control strategy. For example, the working range into which the actual yaw rate falls can be determined, and drive or braking control can be performed based on the control strategy corresponding to the working range. For example, when the working range includes multiple working ranges, each working range corresponds to a different control strategy. The current working range among the multiple working ranges into which the current actual yaw rate falls is determined, and drive or braking control is performed based on the control strategy corresponding to the current working range. The vehicle's drive and braking are coordinated within the current working range to apply drive or braking force to the same wheel, avoiding the simultaneous presence of drive and braking force on the same wheel.

[0069] In the technical solution of this application embodiment, based on the operating characteristics of the drive and braking systems of a distributed drive vehicle, the vehicle's braking reference yaw rate is determined based on vehicle data, and the working range is confirmed accordingly. After confirming the specific working range, drive and braking are coordinated and controlled according to the actual yaw rate and the working range, ensuring that only driving force or braking force exists on the same wheel, avoiding conflict between driving and braking forces on the same wheel, effectively improving brake wear, and enhancing vehicle stability and economy while minimizing modifications to the original system.

[0070] In another example, the vehicle's operating range includes a handling range and a stability range. The operating range can be specifically divided based on the braking reference yaw rate, thereby enabling coordinated control of the vehicle's drive and braking.

[0071] For example, the braking reference yaw rate includes an upper limit and a lower limit of the yaw rate; based on the braking reference yaw rate, determining the operating range for driving braking control of the vehicle includes: firstly, determining the initial braking dead zone based on the upper and lower limits of the yaw rate (see below). Figure 4 Then, based on the initial braking dead zone, the working range is determined (see below). Figure 5 ).

[0072] In the technical solution of this application embodiment, the initial braking dead zone is determined based on the upper limit of the braking yaw rate and the lower limit of the braking reference yaw rate, thereby improving the accuracy of the initial braking dead zone and further accurately determining the working range.

[0073] First, combined Figure 4 This describes an example of determining the initial braking dead zone based on the upper and lower limits of the yaw rate.

[0074] Figure 4 A schematic diagram of the initial braking dead zone of an embodiment of this application is shown.

[0075] For example, the braking reference yaw rate (VDC reference yaw rate) is used as a reference during braking. The braking reference yaw rate planned by the braking system (vehicle stability system) is the braking dead zone. The dead zone means that only the driving force is applied in this area and there is no braking force. The braking reference yaw rate includes an upper limit value and a lower limit value of the yaw rate. The upper limit value and the lower limit value of the braking reference yaw rate can be calculated based on vehicle data according to the following formula (1):

[0076]

[0077] Where, ω r,VDC,up,raw ω is the upper limit of the braking reference yaw rate. r,VDC,lo,raw This refers to the lower limit of the braking reference yaw rate. u, L, u ch.up u ch.lo All represent vehicle data, u ch.up and u ch.lo Here, u represents the upper and lower limits of the characteristic vehicle speed, L represents the longitudinal speed, and L represents the wheelbase. In engineering applications, the characteristic vehicle speed is usually obtained through test calibration. The upper limit of the characteristic vehicle speed generally represents the self-steering characteristics of a car equipped with summer tires and of standard weight, while the lower limit of the characteristic vehicle speed generally represents the self-steering characteristics of a vehicle under special working conditions.

[0078] The upper limit of the yaw rate ω r,VDC,up,raw and the lower limit of yaw rate ω r,VDC,lo,raw The determined yaw rate range is defined as the initial braking dead zone. For example... Figure 4 As shown, Figure 4 The horizontal axis represents the actual yaw rate, and the vertical axis represents the driving reference yaw rate (TVC reference yaw rate) or the braking reference yaw rate (VDC reference yaw rate). The initial braking dead zone is shown in the red shaded area, and the upper and lower limits of this zone are the upper limits of the yaw rate ω, respectively. r,VDC,up,raw and the lower limit of yaw rate ω r, VDC,l o,raw .

[0079] If based on Figure 4The planned initial braking dead zone is used for vehicle drive and braking control. The braking principle aims to bring the vehicle's actual yaw rate close to the braking reference yaw rate (VDC reference yaw rate). Within this initial braking dead zone, the actual yaw rate and the braking reference yaw rate (VDC reference yaw rate) coincide, so braking is ineffective. Therefore, only drive is applied within the initial braking dead zone, allowing only driving force to exist on the same wheel. However, because the difference between the upper and lower limits of this initial braking dead zone is small, the timing of driving force application is less frequent. This makes it easy for the vehicle's control logic to jump out of the initial braking dead zone. After jumping out of the initial braking dead zone, the vehicle may begin braking and decelerating, reducing the duration of vehicle drive action and affecting the vehicle's operational stability.

[0080] Therefore, in order to further improve vehicle handling and stability, increase the duration of vehicle driving, and ensure that the vehicle maintains stability without reducing speed, it is necessary to expand the initial braking dead zone to increase the duration of vehicle driving.

[0081] The target braking dead zone can be obtained by expanding the initial braking dead zone. For example, the initial braking dead zone can be increased based on the braking reference yaw rate offset to obtain the target braking dead zone.

[0082] The following describes how to obtain the braking reference yaw rate offset Δω. r For example, the braking reference yaw rate offset can be determined based on vehicle data.

[0083] Specifically, based on vehicle data, the driving yaw moment limit is determined (e.g., including the maximum yaw moment M). z,drv,max Based on the vehicle's two-degree-of-freedom model, and according to the driving yaw moment limit (e.g., including the maximum yaw moment M), z,drv,max Determine the yaw rate limit (maximum yaw rate); based on the yaw rate limit (maximum yaw rate), determine the braking reference yaw rate offset Δω. r For example, the yaw rate limit (maximum yaw rate) can be used as the braking reference yaw rate offset Δω. r .

[0084] For example, the maximum yaw force achievable by the distributed drive is calculated based on the motor capacity and power limit, as shown in Equation (2):

[0085]

[0086] Among them, M z,drv,max B, T drv,max T drv,min All are vehicle speeds, Mz,drv,max The maximum yaw moment achievable by distributed drive, where B is the wheelbase and T is the maximum yaw moment achievable by distributed drive. drv,max T is the maximum positive torque that the drive motor can output. drv,min The maximum negative torque that the drive motor can output is related to the motor's capacity and power limitations.

[0087] For example, the maximum yaw rate that can be changed by the distributed drive energy is calculated using an improved formula of the vehicle's steady-state two-degree-of-freedom maneuvering model, which is reflected in the maximum yaw moment M. z,drv,max The maximum yaw rate is used as the braking reference yaw rate offset Δω. r The two-degree-of-freedom model is manipulated as shown in equation (3):

[0088]

[0089] Where k1 and k2 are the tire lateral stiffness of the front and rear axles, respectively; β is the center-of-gravity slip angle; a and b are the distances from the center of gravity to the front and rear axles, respectively; δ is the front wheel steering angle; m is the vehicle mass; v is the lateral velocity; u is the longitudinal velocity; and ω... r I is the yaw rate. Z The above parameters represent the yaw moment of inertia of the entire vehicle, and are all vehicle data.

[0090] The above formula is then subjected to steady-state processing (e.g., the differential on the right-hand side of the two-degree-of-freedom model formula is 0), and then the maximum yaw rate Δω after the maximum yaw moment is calculated. r The maximum yaw rate Δω r As a braking reference yaw rate offset Δω r As shown in formula (4):

[0091]

[0092] For example, the VCU (Vehicle Controller) sends the calculated reference yaw rate offset to the BCU (Brake Controller) for scene segmentation and motion planning compensation.

[0093] Obtain the braking reference yaw rate offset Δω r Subsequently, based on the braking reference yaw rate offset Δω r Increase the initial braking dead zone to obtain the target braking dead zone; see below. Figure 5 .

[0094] Figure 5 A schematic diagram of the target braking dead zone according to an embodiment of this application is shown.

[0095] like Figure 5 As shown, Figure 5 For the meaning of the x and y coordinates and the definitions of other parameters, please refer to the reference. Figure 4 .

[0096] For example, the braking reference yaw rate also includes the braking reference yaw rate offset Δω. r Based on the initial braking dead zone, the working range is determined, including: based on the braking reference yaw rate offset Δω. r Increase the initial braking dead zone to obtain the target braking dead zone; based on the target braking dead zone, determine the working range.

[0097] In the technical solution of this application embodiment, the initial braking dead zone is determined based on the braking reference yaw rate. The initial braking dead zone is then increased to obtain the target braking dead zone. Based on the target braking dead zone, the working range (maneuvering range and stability range) is determined. By increasing the braking dead zone while maintaining the original system as much as possible, the effective area of ​​the driving force is increased. The driving force improves wheel maneuverability by allowing the wheels to maintain their speed. Drive or braking coordination control is performed according to the specific working range, ensuring that only driving force or braking force exists on the same wheel. This effectively reduces brake wear and improves vehicle stability and economy. The specific process is described below.

[0098] like Figure 5 As shown, the target braking dead zone is an expanded braking dead zone. In this area, only the driving force acts, and there is no braking force. This increases the area where the driving force acts and decreases the area where the braking force acts. By controlling the driving force, the acceleration stability of the wheels can be improved without reducing the speed, thus improving the vehicle's handling.

[0099] Next, we will introduce how to increase the initial braking dead zone based on the braking reference yaw rate offset to obtain the target braking dead zone.

[0100] For example, based on the braking reference yaw rate offset Δω r The upper and lower limits of the yaw rate are corrected; based on the corrected upper and lower limits of the yaw rate, the target braking dead zone is obtained.

[0101] For example, the correction for the braking reference yaw rate is shown in equations (5) and (6) below:

[0102] ω r,VDC,up =ω r,VDC,up,raw +Δω r (5)

[0103] ω r,VDC,lo =ω r,VDC,lo,raw -Δω r (6)

[0104] The corrected braking reference yaw rate is shown in equation (7) below:

[0105]

[0106] Where, ω r,VDC,up The corrected upper limit of the braking reference yaw rate, ω r,VDC,lo ω is the corrected lower limit of the braking reference yaw rate. rdes,VDC For the corrected braking reference yaw rate, such as Figure 5 The red broken line represents the target braking dead zone. Figure 5 The area shaded in red.

[0107] In another example, after obtaining the target braking dead zone, the target braking dead zone is defined as the control range, and the area outside the target braking dead zone is defined as the stability range.

[0108] In the technical solution of this application embodiment, the initial braking dead zone is increased based on the braking reference yaw rate offset to obtain the target braking dead zone, and the target braking dead zone is determined as the handling range. The area outside the braking dead zone is determined as the stable range, the area where the driving force is increased, and the area where the braking force is reduced, thereby improving vehicle handling while ensuring that the wheel speed does not decrease.

[0109] After dividing the working range into the control range and the stability range, the current range is determined based on the vehicle's actual yaw rate. Based on the vehicle's actual yaw rate and the working range, the vehicle's driving and braking are controlled in a coordinated manner.

[0110] Specifically, based on the vehicle's actual yaw rate, the current range is determined from the control range and the stable range; if the current range is the control range, drive control is applied to the wheels; if the current range is the stable range, drive control or braking control is applied to the wheels. The control logic for the control range and the stable range are explained below.

[0111] First, regarding the control logic of the operating range, when the current range is the operating range, drive control is applied to the wheels to reduce the deviation between the subsequent actual yaw rate and the subsequent drive reference yaw rate.

[0112] When performing drive control, it is necessary to determine the drive reference yaw rate ω. rdes,TVC For reference. Driving reference yaw rate ω rdes,TVC It is related to factors such as stability, wheel longitudinal velocity, wheelbase, and front wheel steering angle. For example, the driving reference yaw rate ω can be determined based on formula (8). rdes,TVC .

[0113]

[0114] Where K is the stability factor, u is the longitudinal speed, L is the wheelbase, and δ is the front wheel steering angle.

[0115] Obtain the driving reference yaw rate ω rdes,TVC Next, based on the deviation between the vehicle's actual yaw rate and the driving reference yaw rate, a first additional yaw moment is determined. Then, based on the first additional yaw moment, the driving torque of the wheels is determined.

[0116] For example, within the operating range, control is performed by a TVC, which is integrated into the VCU. The TVC first uses a PID algorithm to determine the actual yaw rate and the driving reference yaw rate ω. rdes,TVC The deviation calculation requires the first additional yaw moment (additional yaw moment M) to stabilize the vehicle during acceleration. z,req ).

[0117] Then through the first additional yaw moment M z,req Calculate the required drive torque at both wheel ends. The longitudinal force at the wheel end can be calculated first based on the additional yaw moment, and then the drive torque can be calculated based on the longitudinal force at the wheel end. The drive torque is shown in equations (9) and (10) below:

[0118]

[0119]

[0120] Among them, T Drv,reqL and T Drv,reqR T represents the requested torque of the motors on both sides of the vehicle's drive shaft. reqAXLE R is the total driving torque of the drive shaft. w Let B be the wheel rolling radius, B be the drive axle track width, and i be the wheel rolling radius. L and i R This represents the reduction ratio of the motors on both sides.

[0121] After obtaining the driving torque, a PID algorithm is used to drive the reference yaw rate ω. rdes,TVC For reference, the driving torque of the wheel is used to control the wheel drive, so as to reduce the deviation between the subsequent actual yaw rate and the subsequent driving reference yaw rate.

[0122] In the technical solution of this application embodiment, the driving reference yaw rate is related to stability factors, wheel longitudinal speed, wheel wheelbase, and front wheel steering angle. When the current working range is in the operating range, in order to reduce the deviation between the actual yaw rate of the vehicle and the driving reference yaw rate in subsequent driving, a first additional yaw torque is determined based on the deviation between the current actual and reference yaw rates of the vehicle, thereby determining the driving torque of the wheel and then driving the wheel to control the drive. This can improve the vehicle's handling while maintaining the current vehicle speed.

[0123] Next, for the control logic in the stable range, if the current range is stable, drive control or braking control is applied to the wheels. For example, if the current range is stable, the longitudinal force is determined; based on the direction of the longitudinal force, drive control or braking control is applied to the wheels.

[0124] For example, the longitudinal force at the wheel end is a key factor affecting the longitudinal motion of the vehicle. Under the action of the longitudinal force, the vehicle will be affected by resistance. Driving control or braking control based on the direction of the longitudinal force can avoid the complex wheel force caused by the simultaneous existence of driving force and braking force on the same wheel, which would lead to poor vehicle stability. The calculation method of the longitudinal force is explained in detail below.

[0125] First, based on the vehicle's actual yaw rate and braking reference yaw rate ω rdes,VDC The deviation between the two values ​​is used to determine the second additional yaw moment (the calculation method is similar to that of the first additional yaw moment, and will not be repeated here). Then, the longitudinal force is determined based on the second additional yaw moment, so as to determine the driving torque or braking torque of the wheel based on the longitudinal force. When the wheel is driven and controlled based on the driving torque, the deviation between the subsequent actual yaw rate and the subsequent driving reference yaw rate can be reduced. When the wheel is braked and controlled based on the braking torque, the deviation between the subsequent actual yaw rate and the subsequent braking reference yaw rate can be reduced.

[0126] Specifically, when the direction of the longitudinal force is the same as the direction of vehicle travel, drive control is applied to the wheels; when the direction of the longitudinal force is the opposite of the direction of vehicle travel, braking control is applied to the wheels. When the direction of the longitudinal force is the same as the direction of vehicle travel, the longitudinal force is positive. When the direction of the longitudinal force is the opposite of the direction of vehicle travel, the longitudinal force is negative.

[0127] For example, the BCU sends a positive longitudinal force to the VCU, which arbitrates the force and then the drive motor executes it. For instance, it calculates the torque request (drive torque) based on the positive longitudinal force and outputs it. After obtaining the drive torque, it uses a PID algorithm to drive the reference yaw rate ω. rdes,TVC For reference, the wheel drive torque is used to control the wheel drive, thereby reducing the deviation between the subsequent actual yaw rate and the subsequent drive reference yaw rate. The negative longitudinal force is applied by the brake wheel cylinder; for example, the torque request is calculated based on the negative longitudinal force and then output. After obtaining the braking torque, a PID algorithm is used to apply the braking reference yaw rate ω. rdes,VDCFor reference, wheel drive control is performed based on the wheel's braking torque to reduce the deviation between the subsequent actual yaw rate and the subsequent braking reference yaw rate. The calculation method for the torque request is similar to that for the operating range, as explained above.

[0128] In the technical solution of this application embodiment, when the current interval is in a stable interval, the wheels are controlled in a coordinated manner for driving and braking. It is determined whether the direction of the longitudinal force at the wheel end is consistent with the vehicle's driving direction, and corresponding driving or braking control is performed based on the determination result. When the direction of the longitudinal force is consistent with the vehicle's driving direction, driving control is performed; when the direction of the longitudinal force is opposite to the vehicle's driving direction, braking control is performed. This ensures that driving and braking do not coexist on the same wheel, achieving coordinated driving and braking control and guaranteeing the stability and safety of the vehicle.

[0129] Figure 6 A schematic diagram of the drive-brake coordinated control process according to an embodiment of this application is shown.

[0130] For example, such as Figure 6 As shown, the VDC is integrated into the BCU, and the TVC is integrated into the VCU. The VDC performs motion control within the stable zone according to the motion plan, ensuring unified control of braking and drive by distributing torque at the wheel ends, and coordinating wheel-end torque based on the direction of the longitudinal force. When the longitudinal force is negative, it outputs a request for wheel cylinder braking torque. The TVC performs motion control within the operating zone according to the motion plan, distributing and controlling drive by distributing torque at the wheel ends, and coordinating wheel-end torque based on the longitudinal force, outputting a request for drive motor torque. Within the operating zone, the TVC performs drive control, and the VCU acquires the reference yaw rate offset Δω. r The data is sent to the BCU for scene segmentation and motion planning compensation. The VDC activation flag indicates entry into the stable region. Within the stable region, the TVC and VDC need to coordinate control. After entering the stable region, if the BCU calculates the positive longitudinal force (from which the drive torque is derived), it sends a drive torque request to the VCU. The VCU performs drive control based on the drive torque request and then returns a response to the BCU (e.g., a drive motor torque request). The VCU and TVC coordinate control to ensure that upper drive braking on the same wheel is not simultaneously present.

[0131] Figure 7 A block diagram of a vehicle control device according to an embodiment of this application is shown.

[0132] This application provides a vehicle control device 700. Please refer to [link / reference]. Figure 7 The vehicle control unit 700 includes:

[0133] The first determining module 710 is used to determine the vehicle's braking reference yaw rate based on vehicle data.

[0134] The second determining module 720 is used to determine the working range for driving braking control of the vehicle based on the braking reference yaw rate.

[0135] The cooperative control module 730 is used to coordinate the driving and braking of the vehicle based on the vehicle's actual yaw rate and operating range, so as to apply driving or braking force on the same wheel.

[0136] For example, the working range includes a control range and a stable range; the cooperative control module 730 is also used to: determine the current range from the control range and the stable range based on the actual yaw rate of the vehicle; when the current range is the control range, perform drive control on the wheels; when the current range is the stable range, perform drive control or braking control on the wheels.

[0137] For example, when the current interval is a stable interval, driving control or braking control of the wheel includes: determining the longitudinal force when the current interval is a stable interval; and determining whether to drive control or brake control of the wheel based on the direction of the longitudinal force.

[0138] For example, determining the direction of the longitudinal force to drive or brake the wheels includes: driving the wheels when the direction of the longitudinal force is in the same direction as the vehicle's travel; and braking the wheels when the direction of the longitudinal force is in the opposite direction to the vehicle's travel.

[0139] For example, when the current interval is the operating interval, driving control of the wheel includes: determining a first additional yaw moment based on the deviation between the actual yaw rate of the vehicle and the driving reference yaw rate, wherein the driving reference yaw rate is associated with stability factors, wheel longitudinal speed, wheel wheelbase, and front wheel steering angle; determining the driving torque of the wheel based on the first additional yaw moment; and driving control of the wheel based on the driving torque of the wheel to reduce the deviation between the subsequent actual yaw rate and the subsequent driving reference yaw rate.

[0140] For example, when the current interval is a stable interval, determining the longitudinal force includes: determining a second additional yaw moment based on the deviation between the vehicle's actual yaw rate and the braking reference yaw rate; determining the longitudinal force based on the second additional yaw moment, so as to determine the driving torque or braking torque of the wheel based on the longitudinal force; wherein, when the wheel is driven based on the driving torque of the wheel, the deviation between the subsequent actual yaw rate and the subsequent driving reference yaw rate can be reduced, and when the wheel is braked based on the braking torque of the wheel, the deviation between the subsequent actual yaw rate and the subsequent braking reference yaw rate can be reduced.

[0141] For example, the braking reference yaw rate includes an upper limit value and a lower limit value of the yaw rate; the second determining module 720 is further configured to: determine an initial braking dead zone based on the upper limit value and the lower limit value of the yaw rate; and determine a working range based on the initial braking dead zone.

[0142] For example, the braking reference yaw rate also includes a braking reference yaw rate offset; determining the working range based on the initial braking dead zone includes: increasing the initial braking dead zone based on the braking reference yaw rate offset to obtain a target braking dead zone; and determining the working range based on the target braking dead zone.

[0143] For example, determining the working range based on the target braking dead zone includes: defining the target braking dead zone as the operating range; and defining the area outside the target braking dead zone as the stable range.

[0144] For example, the initial braking dead zone includes an upper limit value and a lower limit value of yaw rate; based on the braking reference yaw rate offset, the initial braking dead zone is increased to obtain the target braking dead zone, including: correcting the upper limit value and the lower limit value of yaw rate based on the braking reference yaw rate offset; and obtaining the target braking dead zone based on the corrected upper limit value and the corrected lower limit value of yaw rate.

[0145] For example, the first determining module 710 is further configured to: determine a driving yaw moment limit based on vehicle data; determine a yaw rate limit based on the driving yaw moment limit according to the two-degree-of-freedom model of the vehicle; and determine a braking reference yaw rate offset based on the yaw rate limit.

[0146] It is understood that for a detailed description of the vehicle control device 700, please refer to the description of the vehicle control device method above.

[0147] This application provides a vehicle including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method described in any of the above embodiments.

[0148] This application provides an electronic device, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method in any of the above embodiments.

[0149] This application provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method in any of the above embodiments.

[0150] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequential list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this application, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which programs can be printed, because programs can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0151] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0152] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A vehicle control method, characterized in that, The method includes: Based on vehicle data, determine the vehicle's braking reference yaw rate; Based on the braking reference yaw rate, the working range for driving and braking control of the vehicle is determined. Based on the vehicle's actual yaw rate and the operating range, the vehicle's driving and braking are controlled in a coordinated manner to apply driving or braking force to the same wheel.

2. The method according to claim 1, characterized in that, The operating range includes a control range and a stability range; the coordinated control of the vehicle's drive and braking based on the vehicle's actual yaw rate and the operating range includes: The current interval is determined from the control interval and the stable interval based on the actual yaw rate of the vehicle. When the current interval is the operating interval, drive control is applied to the wheels; When the current interval is the stable interval, drive control or braking control is performed on the wheels.

3. The method according to claim 2, characterized in that, When the current interval is the stable interval, the method of performing drive control or braking control on the wheels includes: If the current interval is the stable interval, determine the longitudinal force; The direction of the longitudinal force determines whether to drive or brake the wheels.

4. The method according to claim 3, characterized in that, The method of determining the direction of the longitudinal force to perform drive control or braking control on the wheel includes: When the direction of the longitudinal force is consistent with the direction of vehicle travel, drive control is applied to the wheels; When the direction of the longitudinal force is in the opposite direction to the vehicle's movement, braking control is applied to the wheels.

5. The method according to any one of claims 2-4, characterized in that, When the current interval is the operating interval, the method of driving the wheels includes: A first additional yaw moment is determined based on the deviation between the vehicle’s actual yaw rate and the driving reference yaw rate, wherein the driving reference yaw rate is associated with stability factors, wheel longitudinal speed, wheelbase, and front wheel steering angle. Based on the first additional yaw moment, the driving torque of the wheel is determined; Based on the driving torque of the wheels, drive control is performed on the wheels to reduce the deviation between the subsequent actual yaw rate and the subsequent drive reference yaw rate.

6. The method according to any one of claims 3-5, characterized in that, Determining the longitudinal force when the current interval is the stable interval includes: The second additional yaw moment is determined based on the deviation between the vehicle’s actual yaw rate and the braking reference yaw rate. Based on the second additional yaw moment, the longitudinal force is determined so as to determine the driving torque or braking torque of the wheel based on the longitudinal force; Specifically, when the driving torque of the wheel is used to control the wheel drive, the deviation between the subsequent actual yaw rate and the subsequent driving reference yaw rate can be reduced. When the braking torque of the wheel is used to control the wheel brake, the deviation between the subsequent actual yaw rate and the subsequent braking reference yaw rate can be reduced.

7. The method according to any one of claims 1-6, characterized in that, The braking reference yaw rate includes an upper limit and a lower limit; determining the operating range for driving and braking control of the vehicle based on the braking reference yaw rate includes: The initial braking dead zone is determined based on the upper and lower limits of the yaw rate. The working range is determined based on the initial braking dead zone.

8. The method according to claim 7, characterized in that, The braking reference yaw rate also includes a braking reference yaw rate offset; determining the working range based on the initial braking dead zone includes: Based on the braking reference yaw rate offset, the initial braking dead zone is increased to obtain the target braking dead zone; The working range is determined based on the target braking dead zone.

9. The method according to claim 8, characterized in that, Determining the working range based on the target braking dead zone includes: The target braking dead zone is defined as the control range; The region outside the target braking dead zone is defined as the stable interval.

10. The method according to claim 8 or 9, characterized in that, The initial braking dead zone includes the upper limit of the yaw rate and the lower limit of the yaw rate; the step of increasing the initial braking dead zone based on the braking reference yaw rate offset to obtain the target braking dead zone includes: Based on the braking reference yaw rate offset, the upper limit value of the yaw rate and the lower limit value of the yaw rate are corrected; The target braking dead zone is obtained based on the corrected upper limit and lower limit of the yaw rate.

11. The method according to any one of claims 8-10, characterized in that, Based on vehicle data, determine the braking reference yaw rate offset, including: Based on vehicle data, determine the limit of drive yaw moment; Based on the two-degree-of-freedom model of the vehicle, the yaw rate limit is determined according to the driving yaw moment limit. Based on the yaw rate limit, the braking reference yaw rate offset is determined.

12. A vehicle control device, characterized in that, The device includes: The first determining module is used to determine the vehicle's braking reference yaw rate based on vehicle data; The second determining module is used to determine the working range for driving braking control of the vehicle based on the braking reference yaw rate. The cooperative control module is used to coordinate the driving and braking of the vehicle based on the vehicle's actual yaw rate and the operating range, so as to apply driving force or braking force on the same wheel.

13. A vehicle comprising a memory and a processor, said memory storing a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1-11.

14. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1-11.

15. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1-11.

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