Vehicle crabbing mode exit control method and related device

Abstract

The invention discloses an exit control method of a vehicle crabbing mode and a related device, and relates to the field of vehicle control, and the method comprises the steps: determining a change state identifier of a steering wheel angle according to the steering wheel angle at a collection moment and the change rate of the steering wheel angle, and determining a rear wheel target turning angle after exiting the crabbing mode according to the vehicle speed and the steering wheel angle at the acquisition moment, determining a rear wheel steering basic rate after exiting the crabbing mode according to the vehicle speed, and performing vehicle running control at least based on the rear wheel steering basic rate, the change state identifier and the rear wheel target turning angle after exiting the crabbing mode. The driving intention of the driver and the rear wheel steering angle range after the crabbing mode is quitted are determined by determining the change state identifier and the rear wheel target steering angle after the crabbing mode is quitted, and the rear wheel steering basic rate is configured to be smaller than the minimum rear wheel steering rate causing vehicle instability. Therefore, the vehicle can be accurately controlled after the crabbing mode is quitted under different driving intentions and vehicle speeds, and the stability of the vehicle is improved.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to a method and device for exiting a vehicle crabging mode. Background Technology

[0002] Crab mode refers to a driving mode in which the rear wheels steer in the same direction as the front wheels, thereby improving the vehicle's agility and stability. However, when the vehicle exits crab mode, the rear wheels switch from steerable in the same direction as the front wheels to steer in the opposite direction. Because the reverse rotation of the rear wheels causes changes in the vehicle's yaw rate, rate of change of yaw rate, and lateral acceleration, excessively large ranges or frequencies of these changes can compromise vehicle stability and affect driving safety. Therefore, improving vehicle stability after exiting crab mode has become a pressing issue. Summary of the Invention

[0003] In view of the above problems, this application provides a method and related device for exiting the vehicle's crabbing mode, so as to improve the driving stability of the vehicle after exiting the crabbing mode. The specific solution is as follows:

[0004] The first aspect of this application provides a method for exiting a vehicle's crabbing mode, comprising:

[0005] The steering wheel angle change status indicator is determined based on the steering wheel angle at the time of data collection and the rate of change of the steering wheel angle, and the target rear wheel turning angle after exiting the crab mode is determined based on the vehicle speed at the time of data collection and the steering wheel angle.

[0006] The rear wheel steering base rate after exiting the crab mode is determined based on the vehicle speed using a preset vehicle motion differential equation. After exiting the crab mode, vehicle driving control is performed based at least on the rear wheel steering base rate, the change state indicator, and the rear wheel target steering angle. The rear wheel steering base rate is less than the minimum rear wheel steering rate that would cause vehicle instability.

[0007] In one possible implementation, determining the steering wheel angle change status indicator based on the steering wheel angle at the time of data acquisition and the rate of change of the steering wheel angle includes:

[0008] A first change amount is determined based on the steering wheel angle at the acquisition time and the steering wheel angle at the adjacent historical acquisition time; a second change amount is determined based on the rate of change at the acquisition time and the rate of change of the steering wheel angle at the adjacent historical acquisition time.

[0009] The content of the change state identifier is determined based on the first change amount and the second change amount.

[0010] In one possible implementation, determining the content of the change state identifier based on the first change amount and the second change amount includes:

[0011] When the value of the first change is within its corresponding first preset range and the value of the second change is within its corresponding second preset range, the output content is the change state indicator without steering wheel operation.

[0012] When both the first change and the second change are positive, and the value of at least one of the first change and the second change is not within its corresponding target preset range, the output content is the change state indicator of the steering wheel turning, and the target preset range is at least one of the first preset range and the second preset range.

[0013] If one of the first change amount and the second change amount is positive and the other is negative, and the value of at least one of the first change amount and the second change amount is not within the corresponding target preset range, the output content is the change state indicator of the steering wheel returning to center.

[0014] In one possible implementation, the vehicle driving control after exiting the crab mode, based at least on the rear wheel steering base rate, the change state indicator, and the target rear wheel steering angle, includes:

[0015] When the change state identifier indicates that there is no steering wheel operation, the rear wheels are controlled to rotate from the current angle to the target rear wheel steering angle according to the rear wheel steering base rate.

[0016] When the change state identifier indicates that the steering wheel is turning, the product of the front wheel angle change rate at the moment of exiting the crab mode, the vehicle speed at the moment of exiting the crab mode, and the steering wheel angle at the moment of exiting the crab mode is determined as the rear wheel control steering rate, and the rear wheels are controlled to rotate to the rear wheel target angle according to the rear wheel control steering rate.

[0017] When the change state indicator indicates that the steering wheel is straightened, it is determined whether the rear wheel steering base rate is within a preset steering rate range. The lower limit of the preset steering rate range is the front wheel steering rate at the moment of exiting the crab mode, and the upper limit of the preset steering rate range is the maximum rear wheel steering rate. When the rear wheel steering base rate is within the preset steering rate range, the rear wheels are controlled to rotate to the target rear wheel angle according to the rear wheel steering base rate. When the rear wheel steering base rate is not within the preset steering rate range, the rear wheels are controlled to rotate to the target rear wheel angle according to the middle value of the preset steering rate range.

[0018] One possible implementation also includes:

[0019] If the difference between the current steering angle of the rear wheel and the target steering angle of the rear wheel is not greater than a preset steering angle threshold, the rear wheel is controlled to rotate to the target steering angle of the rear wheel at a preset minimum steering rate, wherein the preset minimum steering rate is less than the basic steering rate of the rear wheel.

[0020] In one possible implementation, determining the rear wheel steering base rate after exiting the crabging mode based on the vehicle speed using a preset vehicle motion differential equation includes:

[0021] Based on the vehicle speed u, using the formula:

[0022] ,

[0023] The rear wheel steering base rate was obtained. Wherein, k1 is the front wheel lateral stiffness, k2 is the rear wheel lateral stiffness, β is the vehicle's center of gravity sideslip angle, a is the distance from the center of gravity to the front axle, and b is the distance from the center of gravity to the rear axle. It is the yaw rate of the vehicle body. It is the front wheel steering angle, and m is the vehicle mass. It is the vehicle's lateral acceleration. It is the moment of inertia of the vehicle around the coordinate axis that is perpendicular to the ground and around the vehicle's center of mass.

[0024] A second aspect of this application provides a vehicle crab mode exit control system, comprising:

[0025] The parameter determination module is used to determine the change status indicator of the steering wheel angle based on the steering wheel angle at the time of data acquisition and the rate of change of the steering wheel angle, and to determine the target rear wheel turning angle after exiting the crab mode based on the vehicle speed at the time of data acquisition and the steering wheel angle.

[0026] The control module is used to determine the rear wheel steering base rate after exiting the crab mode based on the vehicle speed using a preset vehicle motion differential equation, and to perform vehicle driving control based at least on the rear wheel steering base rate, the change state indicator and the rear wheel target steering angle after exiting the crab mode, wherein the rear wheel steering base rate is less than the minimum rear wheel steering rate that would cause vehicle instability.

[0027] In one possible implementation, the parameter determination module is set to determine the steering wheel angle change status indicator based on the steering wheel angle at the acquisition time and the rate of change of the steering wheel angle:

[0028] A first change amount is determined based on the steering wheel angle at the acquisition time and the steering wheel angle at the adjacent historical acquisition time; a second change amount is determined based on the rate of change at the acquisition time and the rate of change of the steering wheel angle at the adjacent historical acquisition time.

[0029] The content of the change state identifier is determined based on the first change amount and the second change amount.

[0030] In one possible implementation, the parameter determination module is configured to determine the content of the change state identifier based on the first change amount and the second change amount as follows:

[0031] When the value of the first change is within its corresponding first preset range and the value of the second change is within its corresponding second preset range, the output content is the change state indicator without steering wheel operation.

[0032] When both the first change and the second change are positive, and the value of at least one of the first change and the second change is not within its corresponding target preset range, the output content is the change state indicator of the steering wheel turning, and the target preset range is at least one of the first preset range and the second preset range.

[0033] If one of the first change amount and the second change amount is positive and the other is negative, and the value of at least one of the first change amount and the second change amount is not within the corresponding target preset range, the output content is the change state indicator of the steering wheel returning to center.

[0034] In one possible implementation, the control module is configured to perform vehicle driving control based at least on the rear wheel steering base rate, the change state indicator, and the rear wheel target steering angle after exiting the crab mode:

[0035] When the change state identifier indicates that there is no steering wheel operation, the rear wheels are controlled to rotate from the current angle to the target rear wheel steering angle according to the rear wheel steering base rate.

[0036] When the change state identifier indicates that the steering wheel is turning, the product of the front wheel angle change rate at the moment of exiting the crab mode, the vehicle speed at the moment of exiting the crab mode, and the steering wheel angle at the moment of exiting the crab mode is determined as the rear wheel control steering rate, and the rear wheels are controlled to rotate to the rear wheel target angle according to the rear wheel control steering rate.

[0037] When the change state indicator indicates that the steering wheel is straightened, it is determined whether the rear wheel steering base rate is within a preset steering rate range. The lower limit of the preset steering rate range is the front wheel steering rate at the moment of exiting the crab mode, and the upper limit of the preset steering rate range is the maximum rear wheel steering rate. When the rear wheel steering base rate is within the preset steering rate range, the rear wheels are controlled to rotate to the target rear wheel angle according to the rear wheel steering base rate. When the rear wheel steering base rate is not within the preset steering rate range, the rear wheels are controlled to rotate to the target rear wheel angle according to the middle value of the preset steering rate range.

[0038] In one possible implementation, the control module, after exiting the crab mode, is further configured to perform vehicle driving control based at least on the rear wheel steering base rate, the change state indicator, and the rear wheel target steering angle.

[0039] If the difference between the current steering angle of the rear wheel and the target steering angle of the rear wheel is not greater than a preset steering angle threshold, the rear wheel is controlled to rotate to the target steering angle of the rear wheel at a preset minimum steering rate, wherein the preset minimum steering rate is less than the basic steering rate of the rear wheel.

[0040] In one possible implementation, the control module determines the rear wheel steering base rate after exiting the crabging mode based on the vehicle speed using a preset vehicle motion differential equation, including:

[0041] Based on the vehicle speed u, using the formula:

[0042] ,

[0043] The rear wheel steering base rate was obtained. Wherein, k1 is the front wheel lateral stiffness, k2 is the rear wheel lateral stiffness, β is the vehicle's center of gravity sideslip angle, a is the distance from the center of gravity to the front axle, and b is the distance from the center of gravity to the rear axle. It is the yaw rate of the vehicle body. It is the front wheel steering angle, and m is the vehicle mass. It is the vehicle's lateral acceleration. It is the moment of inertia of the vehicle around the coordinate axis that is perpendicular to the ground and around the vehicle's center of mass.

[0044] A third aspect of this application provides a computer program product including computer-readable instructions that, when executed on an electronic device, cause the electronic device to implement the vehicle crabging mode exit control method described in the first aspect or any implementation thereof.

[0045] A fourth aspect of this application provides an electronic device, including at least one processor and a memory connected to the processor, wherein:

[0046] The memory is used to store computer programs;

[0047] The processor is used to execute the computer program to enable the electronic device to implement the vehicle crabging mode exit control method of the first aspect or any implementation thereof.

[0048] The fifth aspect of this application provides a computer storage medium carrying one or more computer programs that, when executed by an electronic device, enable the electronic device to implement a vehicle crabging mode exit control method according to the first aspect or any implementation thereof.

[0049] By employing the aforementioned technical solution, this application provides a vehicle crab mode exit control method and related device. By configuring the system to determine a steering wheel angle change status indicator based on the steering wheel angle and its rate of change at the time of data acquisition, and to determine the target rear wheel steering angle after exiting crab mode based on the vehicle speed and steering wheel angle at the time of data acquisition, this method achieves the determination of the driver's driving intention and the range of rear wheel steering angles after exiting crab mode. This avoids the risk of vehicle instability caused by excessive changes in yaw rate, yaw rate of change, and lateral acceleration due to simply setting a specified rear wheel steering angle in existing technologies. Subsequently, by configuring the system to determine the rear wheel steering base rate after exiting crab mode based on the vehicle speed using a preset vehicle motion differential equation, and since the rear wheel steering base rate is less than the minimum rear wheel steering rate that causes vehicle instability, vehicle driving control is performed at least based on the rear wheel steering base rate, the steering wheel angle change status indicator, and the target rear wheel steering angle after exiting crab mode. This achieves accurate vehicle control after exiting crab mode under different driving intentions and vehicle speeds, avoiding driving safety problems caused by vehicle instability. Attached Figure Description

[0050] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the originals and elements are not necessarily drawn to scale.

[0051] Figure 1 A flowchart of a vehicle crab mode exit control method provided in this application;

[0052] Figure 2 A first control diagram provided for this application;

[0053] Figure 3 A second control diagram provided for this application;

[0054] Figure 4A third control diagram provided for this application;

[0055] Figure 5 A fourth control diagram provided in this application;

[0056] Figure 6 A block diagram of a vehicle crab mode exit control system provided in this application;

[0057] Figure 7 This is a schematic diagram of the structure of an electronic device provided in this application. Detailed Implementation

[0058] The embodiments of this application are described below with reference to the accompanying drawings. The terminology used in the implementation section of this application is for explaining specific embodiments only and is not intended to limit the scope of this application.

[0059] The embodiments of this application will now be described with reference to the accompanying drawings. Those skilled in the art will recognize that, with technological advancements and the emergence of new scenarios, the technical solutions provided in the embodiments of this application are equally applicable to similar technical problems.

[0060] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to those processes, methods, products, or apparatuses.

[0061] The first aspect of this application provides a method for controlling the exit of a vehicle's crabbing mode, such as... Figure 1 As shown, the method for exiting the vehicle's crab mode includes:

[0062] S101. Determine the steering wheel angle change status indicator based on the steering wheel angle and the rate of change of the steering wheel angle at the time of data collection, and determine the target rear wheel turning angle after exiting the crab mode based on the vehicle speed and steering wheel angle at the time of data collection.

[0063] It should be noted that, in practical applications, the above data collection time can be any time during the vehicle's journey.

[0064] It should be noted that in practical applications, the aforementioned steering wheel angle and rate of change of steering wheel angle can be collected by the steering wheel's angle sensor. The steering wheel angle refers to the difference between the steering wheel's rotation angle at the sampling moment and its zero-position angle, and the rate of change of steering wheel angle refers to the rotation speed at which the steering wheel rotates by that angle. Since the steering wheel angle and rate of change of steering wheel angle can characterize the driver's driving intention—for example, when the driver controls the vehicle to turn left, the steering wheel angle will increase, and the rate of change of steering wheel angle will also increase—this application achieves the determination of the driver's driving intention by configuring a steering wheel angle change status indicator based on the steering wheel angle and rate of change of steering wheel angle at the sampling moment.

[0065] It should be noted that in practical application scenarios, there are multiple ways to determine the target rear wheel turning angle after exiting the crab mode based on the vehicle speed and steering wheel angle at the time of data collection. Here, one method is provided as an example, including the following steps A1 to A2.

[0066] Step A1: Obtain the vehicle speed and steering wheel angle at the time of data collection. Then trigger step A2.

[0067] Step A2: From the preset rear wheel angle parameter table, find the rear wheel angle parameter that has a preset correspondence with the vehicle speed and steering wheel angle obtained in step A1 at the time of collection, and determine it as the target rear wheel angle after exiting the crab mode.

[0068] The aforementioned preset rear wheel steering angle parameters include vehicle speed, steering wheel angle, and rear wheel steering angle parameters. By simulating the driving stability of the vehicle at different vehicle speeds and steering wheel angles, the aforementioned rear wheel steering angle parameters are determined based on the proportional relationship between the front wheel steering angle parameters and the rear wheel steering angle parameters. The aforementioned rear wheel steering angle parameters are the maximum rear wheel steering angles that will prevent the vehicle from becoming unstable at the current vehicle speed and steering wheel angle.

[0069] It should be noted that when the driver intends to turn quickly or the rear wheel steering angle is too large, the vehicle's yaw rate, yaw rate change rate, and lateral acceleration will change significantly, thus reducing vehicle stability. This application addresses this by configuring a steering wheel angle change status indicator based on the steering wheel angle and its change rate at the time of data collection, and by determining the target rear wheel steering angle after exiting the crab mode based on the vehicle speed and steering wheel angle at the time of data collection. This achieves the determination of the driver's driving intention and the range of rear wheel steering angle after exiting the crab mode, avoiding the risk of vehicle instability caused by excessive changes in yaw rate, yaw rate change rate, and lateral acceleration resulting from simply setting a specified rear wheel steering angle and dynamically responding, as is common in existing technologies.

[0070] S102. Determine the rear wheel steering base rate after exiting the crab mode based on the vehicle speed using the preset vehicle motion differential equation, and perform vehicle driving control based at least on the rear wheel steering base rate, change status indicator and rear wheel target steering angle after exiting the crab mode. The rear wheel steering base rate is less than the minimum rear wheel steering rate that would cause vehicle instability.

[0071] It should be noted that, in practical applications, the aforementioned preset vehicle motion differential equation can be an equation characterizing the vehicle's lateral and yaw movements. This application configures the system to determine the rear wheel steering base rate after exiting the crabging mode based on the vehicle speed using the preset vehicle motion differential equation. Since the rear wheel steering base rate is less than the minimum rear wheel steering rate that causes vehicle instability, by configuring vehicle driving control after exiting the crabging mode based at least on the rear wheel steering base rate, steering wheel angle change status indicator, and rear wheel target steering angle, accurate vehicle control is achieved after exiting the crabging mode under different driving intentions and vehicle speeds, avoiding driving safety issues caused by vehicle instability.

[0072] It should be noted that, in practical application scenarios, the above-mentioned rear wheel steering baseline rate represents the steering rate baseline value after the rear wheel exits the crab mode, from the angle at the sampling time to the target steering angle of the rear wheel.

[0073] This application configures the system to determine the steering wheel angle change status indicator based on the steering wheel angle and the rate of change of the steering wheel angle at the time of data acquisition, and determines the target rear wheel steering angle after exiting the crab mode based on the vehicle speed and steering wheel angle at the time of data acquisition. This achieves the determination of the driver's driving intention and the range of rear wheel steering angle after exiting the crab mode, avoiding the risk of vehicle instability caused by excessive changes in vehicle yaw rate, yaw rate of change, and lateral acceleration due to setting only a specified rear wheel steering angle in existing technologies. Subsequently, by configuring the system to determine the rear wheel steering base rate after exiting the crab mode based on the vehicle speed using a preset vehicle motion differential equation, and since the rear wheel steering base rate is less than the minimum rear wheel steering rate that causes vehicle instability, the system configures vehicle driving control based at least on the rear wheel steering base rate, the steering wheel angle change status indicator, and the target rear wheel steering angle after exiting the crab mode. This achieves accurate vehicle control after exiting the crab mode under different driving intentions and vehicle speeds, avoiding driving safety problems caused by vehicle instability.

[0074] In one possible implementation, the change status indicator of the steering wheel angle is determined based on the steering wheel angle and the rate of change of the steering wheel angle at the time of data acquisition, including:

[0075] The first change is determined by comparing the steering wheel angle at the time of data collection with the steering wheel angle at adjacent historical data collection times. The second change is determined by comparing the rate of change at the time of data collection with the rate of change of the steering wheel angle at adjacent historical data collection times.

[0076] The content of the change state identifier is determined based on the first change and the second change.

[0077] It should be noted that in practical applications, since the rate of change of the vehicle's steering wheel angle and the line-laying reel angle changes in real time during vehicle operation, this application determines the first change amount based on the steering wheel angle at the time of sampling and the steering wheel angle at adjacent historical sampling times, and determines the second change amount based on the rate of change at the time of sampling and the rate of change of the steering wheel angle at adjacent historical sampling times. This determines the change amount of the steering wheel angle and the change amount of the rate of change of the steering wheel angle between each sampling time, and then uses the change amount to characterize the change characteristics of the vehicle's driving state at the current sampling time relative to the adjacent historical sampling times.

[0078] In one possible implementation, the content of the change state identifier is determined based on the first change and the second change, including:

[0079] When the value of the first change is within its corresponding first preset range and the value of the second change is within its corresponding second preset range, the output content is a change state indicator without steering wheel operation.

[0080] When both the first change and the second change are positive, and the value of at least one of the first change and the second change is not within its corresponding target preset range, the output content is a steering wheel turning status indicator, and the target preset range is at least one of the first preset range and the second preset range.

[0081] If one of the first change and the second change is positive and the other is negative, and the value of at least one of the first change and the second change is not within its corresponding target preset range, the output content is a status indicator indicating that the steering wheel has returned to center.

[0082] In one possible implementation, vehicle driving control is performed after exiting crab mode, based at least on the rear wheel steering base rate, change status indicator, and target rear wheel steering angle, including:

[0083] When the status indicator shows no steering wheel operation, control the rear wheels to rotate from the current angle to the target steering angle according to the basic rear wheel steering rate;

[0084] When the change status indicator indicates steering wheel turning, the product of the front wheel steering angle change rate at the moment of exiting crab mode, the vehicle speed at the moment of exiting crab mode, and the steering wheel angle at the moment of exiting crab mode is determined as the rear wheel control steering rate, and the rear wheels are controlled to rotate to the rear wheel target steering angle according to the rear wheel control steering rate.

[0085] When the status indicator indicates that the steering wheel is straight, determine whether the rear wheel steering base rate is within the preset steering rate range. The lower limit of the preset steering rate range is the front wheel steering rate at the moment of exiting the crab mode, and the upper limit of the preset steering rate range is the maximum rear wheel steering rate. When the rear wheel steering base rate is within the preset steering rate range, control the rear wheels to rotate to the target rear wheel angle according to the rear wheel steering base rate. When the rear wheel steering base rate is not within the preset steering rate range, control the rear wheels to rotate to the target rear wheel angle according to the middle value of the preset steering rate range.

[0086] It should be noted that, in practical applications, there are multiple implementation methods for controlling vehicle movement after exiting crab mode, based at least on the rear wheel steering base rate, change status indicator, and rear wheel target steering angle. One such method is provided here as an example:

[0087] It should be noted that the following are examples of... Figure 2 As for Figure 4 In the control diagram shown, the dashed line labeled 0 is the steering wheel zero-position indicator line, the solid line labeled 1 is the current direction line of the front wheels, the dashed line labeled 2 is the direction line after the front wheels have turned, the solid line labeled 3 is the current direction line of the rear wheels, and the dashed line labeled 4 is the direction line after the rear wheels have turned. The steering wheel zero-position indicator line coincides with the vehicle's centerline, which is the projection of the line connecting the center point of the front and rear of the vehicle onto the horizontal plane.

[0088] like Figure 2 The diagram shown illustrates the first control operation when the status indicator indicates no steering wheel operation. Figure 2 As shown, when there is no steering wheel operation, the current pointing line 1 of the front wheels remains stationary. Therefore, when exiting crab mode, the rear wheels are controlled to rotate from the current angle to the target steering angle according to the rear wheel steering base speed, i.e., as shown... Figure 2 As shown, the rear wheel pointing line rotates from the current rear wheel pointing line 3 to the pointing line 4 after the rear wheel has turned.

[0089] like Figure 3 The diagram shows a second control scheme when the status indicator indicates steering wheel turning. (Example:) Figure 3 As shown, when the steering wheel is turned, the front wheels rotate from the current pointing line 1 to the pointing line 2 after the front wheels have turned. Therefore, when exiting the crab mode, the product of the front wheel steering angle change rate at the moment of exiting the crab mode, the vehicle speed at the moment of exiting the crab mode, and the steering wheel angle at the moment of exiting the crab mode is determined as the rear wheel control steering rate. The rear wheels are then controlled to rotate to the target rear wheel steering angle according to this rear wheel control steering rate, i.e., as shown... Figure 3 As shown, the rear wheel pointing line rotates from the current rear wheel pointing line 3 to the pointing line 4 after the rear wheel has turned.

[0090] like Figure 4The diagram shown illustrates the third control mechanism when the steering wheel is returned to center, as indicated by the status indicator. Figure 4 As shown, when the steering wheel returns to center, the front wheels rotate from the current pointing line 1 to the steering wheel zero-position indicator line 0. When exiting the crab mode, it is determined whether the rear wheel steering base rate is within a preset steering rate range. The lower limit of the preset steering rate range is the front wheel steering rate at the moment of exiting crab mode, and the upper limit is the maximum rear wheel steering rate. When the rear wheel steering base rate is within the preset steering rate range, the rear wheels are controlled to rotate at the rear wheel steering base rate to the target rear wheel turning angle. When the rear wheel steering base rate is not within the preset steering rate range, the rear wheels are controlled to rotate at the midpoint of the preset steering rate range to the target rear wheel turning angle, i.e., as shown... Figure 4 As shown, the rear wheel pointing line rotates from the current rear wheel pointing line 3 to the pointing line 4 after the rear wheel has turned.

[0091] It should be noted that, in practical application scenarios, for the above... Figure 4 Before the steering wheel is straightened, the rear wheels are in one of two modes: the first is that the front and rear wheels are in the same direction, and the second is that the front and rear wheels are in opposite directions. At this time, the direction line 4 after the rear wheels turn coincides with the zero-position indicator line 0 of the steering wheel.

[0092] One possible implementation also includes:

[0093] If the difference between the current steering angle of the rear wheel and the target steering angle of the rear wheel is not greater than the preset steering angle threshold, the rear wheel is controlled to rotate to the target steering angle at a preset minimum steering rate. The preset minimum steering rate is less than the base steering rate of the rear wheel.

[0094] It should be noted that, in practical applications, the fourth control diagram of the control method described above, which controls the rear wheels to rotate to the target rear wheel angle at a preset minimum steering rate when the difference between the current rear wheel angle and the target rear wheel angle is not greater than a preset angle threshold, is shown below. Figure 5 As shown:

[0095] The dashed line labeled 5 is the rear wheel pointing line corresponding to the target rear wheel turning angle; the solid line labeled 6 is the current pointing line of the rear wheels when exiting crab mode; and the dashed line labeled 7 is the pointing line when the rear wheels rotate to a position with a preset turning angle threshold relative to the target rear wheel turning angle. If the difference between the current rear wheel turning angle and the target rear wheel turning angle is not greater than the preset turning angle threshold, the rear wheels are controlled to switch from rotating at the base rear wheel steering rate to rotating at the preset minimum steering rate.

[0096] It should be noted that this application controls the rear wheels to rotate to the target rear wheel angle at a preset minimum steering rate when the difference between the current rear wheel angle and the target rear wheel angle is not greater than a preset steering angle threshold. The preset minimum steering rate is less than the basic steering rate of the rear wheels, thereby avoiding the impact force on the steering mechanism when rotating to the target rear wheel angle at the basic steering rate of the rear wheels, thus extending the service life of the steering mechanism.

[0097] In one possible implementation, the base steering rate of the rear wheels after exiting crabging mode is determined based on the vehicle speed using a preset vehicle motion differential equation, including:

[0098] Based on the vehicle speed u, using the formula:

[0099] ,

[0100] Calculate the rear wheel steering base rate Where k1 is the front wheel sideslip stiffness, k2 is the rear wheel sideslip stiffness, β is the vehicle's center of gravity sideslip angle, a is the distance from the center of gravity to the front axle, and b is the distance from the center of gravity to the rear axle. It is the yaw rate of the vehicle body. It is the front wheel steering angle, and m is the vehicle mass. It is the vehicle's lateral acceleration. It is the moment of inertia of the vehicle around the coordinate axis that is perpendicular to the ground and around the vehicle's center of mass.

[0101] The second aspect of this application provides a vehicle crab mode exit control system, such as... Figure 6 As shown, it includes:

[0102] The parameter determination module 601 is used to determine the change status indicator of the steering wheel angle based on the steering wheel angle and the rate of change of the steering wheel angle at the time of data acquisition, and to determine the target rear wheel turning angle after exiting the crab mode based on the vehicle speed and steering wheel angle at the time of data acquisition.

[0103] The control module 602 is used to determine the rear wheel steering base rate after exiting the crab mode based on the vehicle speed using a preset vehicle motion differential equation, and to perform vehicle driving control based at least on the rear wheel steering base rate, the change status indicator and the rear wheel target steering angle after exiting the crab mode, wherein the rear wheel steering base rate is less than the minimum rear wheel steering rate that would cause vehicle instability.

[0104] In one possible implementation, the parameter determination module 601 is set to determine the steering wheel angle change status indicator based on the steering wheel angle and the rate of change of the steering wheel angle at the time of data acquisition as follows:

[0105] The first change is determined by comparing the steering wheel angle at the time of data collection with the steering wheel angle at adjacent historical data collection times. The second change is determined by comparing the rate of change at the time of data collection with the rate of change of the steering wheel angle at adjacent historical data collection times.

[0106] The content of the change state identifier is determined based on the first change and the second change.

[0107] In one possible implementation, the parameter determination module 601 is configured to determine the content of the change state identifier based on the first change amount and the second change amount as follows:

[0108] When the value of the first change is within its corresponding first preset range and the value of the second change is within its corresponding second preset range, the output content is a change state indicator without steering wheel operation.

[0109] When both the first change and the second change are positive, and the value of at least one of the first change and the second change is not within its corresponding target preset range, the output content is a steering wheel turning status indicator, and the target preset range is at least one of the first preset range and the second preset range.

[0110] If one of the first change and the second change is positive and the other is negative, and the value of at least one of the first change and the second change is not within its corresponding target preset range, the output content is a status indicator indicating that the steering wheel has returned to center.

[0111] In one possible implementation, the control module 602 described above is configured to perform vehicle driving control based at least on the rear wheel steering base rate, change status indicator, and rear wheel target steering angle after exiting the crab mode:

[0112] When the status indicator shows no steering wheel operation, control the rear wheels to rotate from the current angle to the target steering angle according to the basic rear wheel steering rate;

[0113] When the change status indicator indicates steering wheel turning, the product of the front wheel steering angle change rate at the moment of exiting crab mode, the vehicle speed at the moment of exiting crab mode, and the steering wheel angle at the moment of exiting crab mode is determined as the rear wheel control steering rate, and the rear wheels are controlled to rotate to the rear wheel target steering angle according to the rear wheel control steering rate.

[0114] When the status indicator indicates that the steering wheel is straight, determine whether the rear wheel steering base rate is within the preset steering rate range. The lower limit of the preset steering rate range is the front wheel steering rate at the moment of exiting the crab mode, and the upper limit of the preset steering rate range is the maximum rear wheel steering rate. When the rear wheel steering base rate is within the preset steering rate range, control the rear wheels to rotate to the target rear wheel angle according to the rear wheel steering base rate. When the rear wheel steering base rate is not within the preset steering rate range, control the rear wheels to rotate to the target rear wheel angle according to the middle value of the preset steering rate range.

[0115] In one possible implementation, when the control module 602 performs vehicle driving control based at least on the rear wheel steering base rate, the change state indicator, and the rear wheel target steering angle after exiting the crab mode, it is also configured to:

[0116] If the difference between the current steering angle of the rear wheel and the target steering angle of the rear wheel is not greater than the preset steering angle threshold, the rear wheel is controlled to rotate to the target steering angle at a preset minimum steering rate. The preset minimum steering rate is less than the base steering rate of the rear wheel.

[0117] In one possible implementation, the control module 602 determines the rear wheel steering base rate after exiting the crabging mode based on the vehicle speed using a preset vehicle motion differential equation, including:

[0118] Based on the vehicle speed u, using the formula:

[0119] ,

[0120] Calculate the rear wheel steering base rate Where k1 is the front wheel sideslip stiffness, k2 is the rear wheel sideslip stiffness, β is the vehicle's center of gravity sideslip angle, a is the distance from the center of gravity to the front axle, and b is the distance from the center of gravity to the rear axle. It is the yaw rate of the vehicle body. It is the front wheel steering angle, and m is the vehicle mass. It is the vehicle's lateral acceleration. It is the moment of inertia of the vehicle around the coordinate axis that is perpendicular to the ground and around the vehicle's center of mass.

[0121] A third aspect of this application provides a computer program product including computer-readable instructions that, when executed on an electronic device, cause the electronic device to implement the vehicle crabging mode exit control method described in the first aspect or any implementation thereof.

[0122] A fourth aspect of this application provides an electronic device, including at least one processor and a memory connected to the processor, wherein:

[0123] Memory is used to store computer programs;

[0124] The processor is used to execute computer programs to enable electronic devices to implement the vehicle crabging mode exit control method of the first aspect or any implementation thereof.

[0125] A schematic diagram of the structure of an electronic device is provided in the fourth aspect of this application, as shown below. Figure 7 As shown. The electronic devices in the embodiments of this application may include, but are not limited to, fixed terminals such as mobile phones, laptops, PDAs (personal digital assistants), PADs (tablet computers), desktop computers, etc. Figure 7 The electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0126] like Figure 7 As shown, the electronic device may include a processing unit (e.g., a central processing unit, a graphics processing unit, etc.) 701, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 702 or a program loaded from a storage device 708 into a random access memory (RAM) 703. When the electronic device is powered on, the RAM 703 also stores various programs and data required for the operation of the electronic device. The processing unit 701, ROM 702, and RAM 703 are interconnected via a bus 704. An input / output (I / O) interface 705 is also connected to the bus 704.

[0127] Typically, the following devices can be connected to I / O interface 705: input devices 706 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 707 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 708 including, for example, memory cards, hard drives, etc.; and communication devices 709. Communication device 709 allows electronic devices to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 7 Electronic devices with various devices are shown, but it should be understood that it is not required to implement or have all of the devices shown. More or fewer devices may be implemented or have alternatively.

[0128] The fifth aspect of this application provides a computer storage medium carrying one or more computer programs, which, when executed by an electronic device, enable the electronic device to exit the vehicle crabging mode control method described in the first aspect or any implementation thereof.

[0129] It should also be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. In addition, in the accompanying drawings of the device embodiments provided in this application, the connection relationship between modules indicates that they have a communication connection, which can be implemented as one or more communication buses or signal lines.

[0130] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware, or it can be implemented by special-purpose hardware including application-specific integrated circuits, special-purpose CPUs, special-purpose memory, special-purpose components, etc. Generally, any function performed by a computer program can be easily implemented by corresponding hardware, and the specific hardware structure used to implement the same function can also be diverse, such as analog circuits, digital circuits, or special-purpose circuits. However, for this application, software program implementation is more often the preferred implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a readable storage medium, such as a computer floppy disk, USB flash drive, mobile hard disk, ROM, RAM, magnetic disk, or optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, training equipment, or network device, etc.) to execute the methods of the various embodiments of this application.

[0131] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product.

[0132] A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this application is generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions may be transmitted from one website, computer, training device, or data center to another website, computer, training device, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a training device or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

Claims

1. A method for exiting a vehicle crabbing mode, characterized in that, include: The steering wheel angle change status indicator is determined based on the steering wheel angle at the time of data collection and the rate of change of the steering wheel angle, and the target rear wheel turning angle after exiting the crab mode is determined based on the vehicle speed at the time of data collection and the steering wheel angle. The rear wheel steering base rate after exiting the crab mode is determined based on the vehicle speed using a preset vehicle motion differential equation. After exiting the crab mode, vehicle driving control is performed based at least on the rear wheel steering base rate, the change state indicator, and the rear wheel target steering angle. The rear wheel steering base rate is less than the minimum rear wheel steering rate that would cause vehicle instability.

2. The vehicle crab mode exit control method according to claim 1, characterized in that, The step of determining the steering wheel angle change status indicator based on the steering wheel angle at the time of data acquisition and the rate of change of the steering wheel angle includes: A first change amount is determined based on the steering wheel angle at the acquisition time and the steering wheel angle at the adjacent historical acquisition time; a second change amount is determined based on the rate of change at the acquisition time and the rate of change of the steering wheel angle at the adjacent historical acquisition time. The content of the change state identifier is determined based on the first change amount and the second change amount.

3. The vehicle crab mode exit control method according to claim 2, characterized in that, The determination of the change state identifier based on the first change and the second change includes: When the value of the first change is within its corresponding first preset range and the value of the second change is within its corresponding second preset range, the output content is the change state indicator without steering wheel operation. When both the first change and the second change are positive, and the value of at least one of the first change and the second change is not within its corresponding target preset range, the output content is the change state indicator of the steering wheel turning, and the target preset range is at least one of the first preset range and the second preset range. If one of the first change amount and the second change amount is positive and the other is negative, and the value of at least one of the first change amount and the second change amount is not within the corresponding target preset range, the output content is the change state indicator of the steering wheel returning to center.

4. The vehicle crab mode exit control method according to claim 3, characterized in that, The method of controlling vehicle movement after exiting the crab mode, based at least on the rear wheel steering base rate, the change state indicator, and the rear wheel target steering angle, includes: When the change state identifier indicates that there is no steering wheel operation, the rear wheels are controlled to rotate from the current angle to the target rear wheel steering angle according to the rear wheel steering base rate. When the change state identifier indicates that the steering wheel is turning, the product of the front wheel angle change rate at the moment of exiting the crab mode, the vehicle speed at the moment of exiting the crab mode, and the steering wheel angle at the moment of exiting the crab mode is determined as the rear wheel control steering rate, and the rear wheels are controlled to rotate to the rear wheel target angle according to the rear wheel control steering rate. When the change state indicator indicates that the steering wheel is straightened, it is determined whether the rear wheel steering base rate is within a preset steering rate range. The lower limit of the preset steering rate range is the front wheel steering rate at the moment of exiting the crab mode, and the upper limit of the preset steering rate range is the maximum rear wheel steering rate. When the rear wheel steering base rate is within the preset steering rate range, the rear wheels are controlled to rotate to the target rear wheel angle according to the rear wheel steering base rate. When the rear wheel steering base rate is not within the preset steering rate range, the rear wheels are controlled to rotate to the target rear wheel angle according to the middle value of the preset steering rate range.

5. The vehicle crab mode exit control method according to claim 4, characterized in that, Also includes: If the difference between the current steering angle of the rear wheel and the target steering angle of the rear wheel is not greater than a preset steering angle threshold, the rear wheel is controlled to rotate to the target steering angle of the rear wheel at a preset minimum steering rate, wherein the preset minimum steering rate is less than the basic steering rate of the rear wheel.

6. The vehicle crab mode exit control method according to claim 1, characterized in that, The step of determining the rear wheel steering base rate after exiting crab mode based on the vehicle speed using a preset vehicle motion differential equation includes: Based on the vehicle speed u, using the formula: ， The rear wheel steering base rate was obtained. Wherein, k1 is the front wheel lateral stiffness, k2 is the rear wheel lateral stiffness, β is the vehicle's center of gravity sideslip angle, a is the distance from the center of gravity to the front axle, and b is the distance from the center of gravity to the rear axle. It is the yaw rate of the vehicle body. It is the front wheel steering angle, and m is the vehicle mass. It is the vehicle's lateral acceleration. It is the moment of inertia of the vehicle around the coordinate axis that is perpendicular to the ground and around the vehicle's center of mass.

7. A vehicle crab mode exit control system, characterized in that, include: The parameter determination module is used to determine the change status indicator of the steering wheel angle based on the steering wheel angle at the time of data acquisition and the rate of change of the steering wheel angle, and to determine the target rear wheel turning angle after exiting the crab mode based on the vehicle speed at the time of data acquisition and the steering wheel angle. The control module is used to determine the rear wheel steering base rate after exiting the crab mode based on the vehicle speed using a preset vehicle motion differential equation, and to perform vehicle driving control based at least on the rear wheel steering base rate, the change state indicator and the rear wheel target steering angle after exiting the crab mode, wherein the rear wheel steering base rate is less than the minimum rear wheel steering rate that would cause vehicle instability.

8. A computer program product, characterized in that, Includes computer-readable instructions that, when executed on an electronic device, cause the electronic device to implement the vehicle crabging mode exit control method as described in any one of claims 1 to 6.

9. An electronic device, characterized in that, It includes at least one processor and a memory connected to the processor, wherein: The memory is used to store computer programs; The processor is used to execute the computer program to enable the electronic device to implement the vehicle crab mode exit control method as described in any one of claims 1 to 6.

10. A computer storage medium, characterized in that, The storage medium carries one or more computer programs that, when executed by an electronic device, enable the electronic device to implement the vehicle crabging mode exit control method as described in any one of claims 1 to 6.

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