Active control method and system for vehicle steering, electronic equipment and medium

Abstract

The invention relates to the technical field of automobile body posture control, and discloses an active control method and system for vehicle steering, electronic equipment and a medium, and the method comprises the following steps: when a vehicle is in an insufficient steering state, obtaining a first front wheel side slip angle and a second front wheel side slip angle; determining a vehicle understeering degree coefficient according to the first front wheel slip angle and the second front wheel slip angle; determining a vehicle driving condition according to the vehicle steering insufficiency coefficient; and adjusting the brake torque of the inner side wheel of the front and rear wheels or the brake torque of the rear wheel shaft through the vehicle steering insufficiency degree coefficient according to the vehicle driving working condition. According to the method, the vehicle driving condition is judged by adding the vehicle steering insufficiency coefficient, the braking torque of different parts is adjusted through the vehicle steering insufficiency coefficient according to different working conditions, the vehicle body posture is corrected in advance, a driver feels smooth transition, and the vehicle maneuverability is improved.

Description

Background Art

[0002] In the field of chassis control, the current control of vehicle understeer is mainly through the intervention of the body stability program (ESP). By processing signals such as vehicle speed, lateral acceleration, and steering wheel angle, the body stability system calculates whether the current vehicle is in an understeer state. The body stability system adjusts the braking force distribution of the braking system after calculation, thereby correcting the vehicle's understeer phenomenon and maintaining the stability of the vehicle body.

[0003] However, when the above method is used to correct the vehicle's understeer, the body stability system will quickly intervene when it recognizes the vehicle's understeer, and correct the vehicle's trajectory by adjusting the wheel braking force distribution. This rapid intervention will change the driver's driving experience, especially in some extreme driving conditions. The intervention of the body stability system may make the driver feel that the vehicle's response is not direct enough or is "sluggish." Summary of the invention

[0004] In order to overcome the problem that the body stability system will quickly intervene when it recognizes that the vehicle is understeering, and correct the vehicle's driving trajectory by adjusting the wheel braking force distribution, and this rapid intervention will change the driver's driving experience, the present invention provides an active control method, system, electronic device and medium for vehicle steering.

[0005] In a first aspect, in order to solve the above technical problems, the present invention provides an active control method for vehicle steering, comprising:

[0006] When the vehicle is in understeering, obtaining a first front wheel sideslip angle in a rectangular coordinate system of the vehicle body and a second front wheel sideslip angle in a rectangular coordinate system of the front wheels;

[0007] determining a vehicle understeering degree coefficient according to a first front wheel sideslip angle and a second front wheel sideslip angle;

[0008] Determine the vehicle driving condition according to the vehicle understeering degree coefficient;

[0009] According to the vehicle's driving conditions, the braking torque of the inner wheels of the front and rear wheels, or the braking torque of the rear axle is adjusted by the vehicle's understeering degree coefficient.

[0010] In a second aspect, the present invention provides an active control system for vehicle steering, comprising:

[0011] A front wheel sideslip angle acquisition module, used for acquiring a first front wheel sideslip angle in a rectangular coordinate system of a vehicle body and a second front wheel sideslip angle in a rectangular coordinate system of a front wheel when the vehicle is in an understeering state;

[0012] A vehicle understeering degree coefficient determination module, used for determining the vehicle understeering degree coefficient according to the first front wheel sideslip angle and the second front wheel sideslip angle;

[0013] A vehicle driving condition determination module, used for determining the vehicle driving condition according to the vehicle understeering degree coefficient;

[0014] The active control module is used to adjust the braking torque of the inner wheels of the front and rear wheels, or the braking torque of the rear axle through the vehicle understeering degree coefficient according to the vehicle driving condition.

[0015] In a third aspect, the present invention provides a computing device, including a memory, a processor, and a program stored in the memory and running on the processor, and when the processor executes the program, the steps of an active control method for vehicle steering as described above are implemented.

[0016] In a fourth aspect, the present invention provides a computer-readable storage medium, in which instructions are stored. When the instructions are executed on a terminal device, the terminal device executes the steps of a method for active control of vehicle steering as described above.

[0017] The beneficial effect of the present invention is that when the vehicle is in an understeering state, the present application does not allow the body stability system to intervene quickly, but instead determines the vehicle understeering degree coefficient through the first front wheel sideslip angle and the second front wheel sideslip angle, and determines the vehicle driving condition according to the vehicle understeering degree coefficient, so as to adjust the braking torque of different components through the vehicle understeering degree coefficient under different vehicle driving conditions, correct the body posture in advance, let the driver feel a smooth transition, and improve the vehicle's maneuverability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0019] Figure 1 A schematic flow chart of an active control method for vehicle steering according to an embodiment of the present invention;

[0020] Figure 2 A schematic flow chart of an active control method for vehicle steering according to another embodiment of the present invention;

[0021] Figure 3 The figure is a schematic diagram of the structure of an active control system for vehicle steering according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] The following examples are provided to further explain and supplement the present invention and do not constitute any limitation to the present invention.

[0023] The following describes an active control method, system, electronic device and medium for vehicle steering according to an embodiment of the present invention in conjunction with the accompanying drawings.

[0024] like Figure 1As shown, the present invention provides an active control method for vehicle steering, comprising:

[0025] S1. When the vehicle is in an understeering state, a first front wheel sideslip angle in a rectangular coordinate system of the vehicle body and a second front wheel sideslip angle in a rectangular coordinate system of the front wheels are obtained.

[0026] S2. Determine a vehicle understeering degree coefficient according to the first front wheel sideslip angle and the second front wheel sideslip angle.

[0027] S3. Determine the vehicle driving condition according to the vehicle understeering degree coefficient.

[0028] S4. According to the vehicle driving condition, the braking torque of the inner wheels of the front and rear wheels or the braking torque of the rear wheel axle is adjusted by the vehicle understeering degree coefficient.

[0029] In the present embodiment, when the vehicle is in the state of understeering, the body stability system will not intervene quickly. Instead, the vehicle understeering degree coefficient is determined by the first front wheel sideslip angle and the second front wheel sideslip angle, and the vehicle driving condition is determined according to the vehicle understeering degree coefficient. Under different vehicle driving conditions, the braking torque of different components is adjusted by the vehicle understeering degree coefficient, the understeering is controlled in advance, the body posture is corrected in advance, the driver can feel a smooth transition, and the vehicle maneuverability is improved.

[0030] Optionally, when the vehicle is in understeering, a first front wheel sideslip angle in a rectangular coordinate system of the vehicle body and a second front wheel sideslip angle in a rectangular coordinate system of the front wheels are obtained, and the formula is as follows:

[0031]

[0032] Among them, β So V is the first front wheel side slip angle in the rectangular coordinate system of the vehicle body; yo V is the y-direction speed of the front wheel in the rectangular coordinate system of the vehicle body; xo is the speed of the front wheel in the x direction in the rectangular coordinate system of the vehicle body, β So’ V is the second front wheel side slip angle in the front wheel rectangular coordinate system; yo’ V is the speed of the front wheel in the y direction in the front wheel rectangular coordinate system; xo’ is the speed of the front wheel in the x direction at right angles to the front wheel.

[0033] In this embodiment, the steering degree of the vehicle can be obtained by using the first front wheel slip angle in the rectangular coordinate system of the vehicle body and the second front wheel slip angle in the rectangular coordinate system of the front wheel, thereby calculating the vehicle understeering degree coefficient, optimizing the limitation of using only the yaw rate to judge the vehicle understeering, and preventing misjudgment.

[0034] Optionally, determining the vehicle understeering degree coefficient according to the first front wheel sideslip angle and the second front wheel sideslip angle includes:

[0035] The absolute value of the difference between the first front wheel sideslip angle and the second front wheel sideslip angle is used as the third front wheel sideslip angle under vehicle understeering;

[0036] The product of the third front wheel sideslip angle and the first coefficient is used as the vehicle understeering degree coefficient; wherein the first coefficient takes a first preset value according to different vehicle models.

[0037] In this embodiment, the absolute value of the difference between the first front wheel slip angle and the second front wheel slip angle is used as the third front wheel slip angle under vehicle understeering, and the formula is as follows:

[0038] β US =|β So -β So’ |

[0039] Among them, β US Indicates the third front wheel slip angle.

[0040] In this embodiment, the product of the third front wheel sideslip angle and the first coefficient is used as the vehicle understeering degree coefficient, and the formula is as follows:

[0041] p=k s *β US

[0042] Where p represents the vehicle understeering coefficient, k s represents the first coefficient. In this embodiment, k s Different values ​​(first preset values) will be taken according to different vehicle models, and a corresponding relationship can be established between each vehicle model and its first preset value by constructing a relationship table.

[0043] In this embodiment, when the vehicle understeers through the yaw rate, it can be considered that the vehicle is about to understeer, and a prediction of the vehicle understeer is made. Then, the sizes of the front wheel slip angles in different coordinate systems are subtracted and the absolute values ​​are taken to avoid the influence of positive and negative signs when turning left or right. The absolute value of the front wheel slip angle is positively correlated with the vehicle understeer degree coefficient, that is, the understeer is predicted through the yaw rate. When the prediction result appears, the vehicle understeer degree coefficient is calculated through the front wheel slip angles in different coordinate systems.

[0044] Optionally, the vehicle driving condition includes a vehicle steady-state driving condition;

[0045] According to the vehicle's driving conditions, the braking torque of the inner wheels of the front and rear wheels, or the braking torque of the rear axle, is adjusted by the vehicle's understeering coefficient, including:

[0046] When the vehicle driving condition is a steady-state driving condition, the braking torque of the inner wheels of the front and rear wheels is adjusted according to the current vehicle speed, the second coefficient, and the vehicle understeer degree coefficient; wherein the second coefficient takes a second preset value according to different vehicle models.

[0047] In this embodiment, when the vehicle is in steady-state driving condition, the braking torque is positively correlated with the vehicle speed and the vehicle understeering coefficient, and the braking torque is distributed to the inner wheels of the front and rear wheels, and the vehicle body posture is corrected through torque distribution.

[0048] In this embodiment, when the vehicle driving condition is a steady-state driving condition, the braking torque of the inner wheels of the front and rear wheels is adjusted according to the current vehicle speed, the second coefficient, and the vehicle understeering degree coefficient. The formula is as follows:

[0049] M1=k u *v+k u *p

[0050] Among them, M1 represents the braking torque of the inner wheels of the front and rear wheels, v represents the current vehicle speed, and k u represents the second coefficient. In this embodiment, k u Different values ​​(second preset values) will be taken according to different vehicle models. By constructing a relationship table, a corresponding relationship can be established between each vehicle model and its second preset value.

[0051] Optionally, the vehicle driving condition further includes an extreme vehicle driving condition;

[0052] According to the vehicle's driving conditions, the braking torque of the inner wheels of the front and rear wheels, or the braking torque of the rear axle, is adjusted by the vehicle's understeering coefficient, including:

[0053] When the vehicle driving condition is an extreme vehicle driving condition, the braking torque of the rear axle is adjusted according to the current vehicle speed, the third coefficient, and the vehicle understeering degree coefficient; wherein the third coefficient takes a third preset value according to different vehicle models.

[0054] In this embodiment, when the vehicle is in extreme driving conditions, the braking torque is positively correlated with the vehicle speed and the vehicle understeer coefficient, and the braking torque is distributed to the rear axle of the rear wheels, and the vehicle body posture is corrected by reducing the vehicle speed.

[0055] In this embodiment, when the vehicle driving condition is an extreme vehicle driving condition, the braking torque of the rear axle is adjusted according to the current vehicle speed, the third coefficient, and the vehicle understeering degree coefficient. The formula is as follows:

[0056] M2=k e *v+k e *p

[0057] Among them, M2 represents the braking torque of the rear axle, v represents the current vehicle speed, and ke represents the second coefficient. In this embodiment, k e Different values ​​(third preset values) will be taken according to different vehicle models. By constructing a relationship table, a corresponding relationship can be established between each vehicle model and its third preset value.

[0058] In this embodiment, the vehicle speed can be reduced under extreme driving conditions (such as high-speed cornering conditions), so that the vehicle body stability system is controlled in the optimal control range, thereby optimizing the performance of the vehicle body stability system.

[0059] Optionally, the vehicle driving condition further includes a vehicle stable driving condition;

[0060] According to the vehicle driving condition, the braking torque of the inner wheels of the front and rear wheels or the braking torque of the rear axle is adjusted by the vehicle understeering degree coefficient, and also includes:

[0061] If the vehicle is in a stable driving condition, the vehicle steering is controlled by the body stability system.

[0062] In this embodiment, the existing vehicle body stability system function can be combined and extended to steady-state conditions and extreme conditions, so as to achieve understeer control of the vehicle under all conditions and improve driving stability and safety.

[0063] Optionally, when the vehicle is in understeering, obtaining a first front wheel sideslip angle in a rectangular coordinate system of the vehicle body and a second front wheel sideslip angle in a rectangular coordinate system of the front wheel further includes:

[0064] When the vehicle is turning, if the actual yaw rate collected by the vehicle sensor is less than the expected yaw rate, it is determined that the vehicle is understeering.

[0065] like Figure 2 As shown, another embodiment is used to illustrate an active control method for vehicle steering, which is specifically as follows:

[0066] When the vehicle is turning, if the actual yaw rate collected by the vehicle sensor is less than the expected yaw rate, it is judged that the vehicle is understeering. At this time, the front wheel slip angle (including the front wheel slip angle in the rectangular coordinate system of the vehicle body and the front wheel slip angle in the rectangular coordinate system of the front wheel) is obtained.

[0067] The understeering coefficient of the vehicle is calculated by the front wheel slip angle, and the vehicle driving condition is judged by the understeering coefficient. For example:

[0068] The numerical range of the vehicle understeering degree coefficient is (0~1). If the calculated vehicle understeering degree coefficient is 0.1~0.3, the vehicle understeering degree coefficient triggers the vehicle steady-state driving condition when it is in this interval. If the calculated vehicle understeering degree coefficient is 0.9~1, the vehicle understeering degree coefficient triggers the vehicle extreme driving condition when it is in this interval. If the calculated vehicle understeering degree coefficient is 0.3~0.8, the vehicle understeering degree coefficient triggers the vehicle stable driving condition when it is in this interval.

[0069] If the vehicle is in an extreme driving condition, the target braking torque is calculated and distributed to the axle end (rear axle) to reduce the vehicle speed and keep it within the working range where the body stability system can intervene.

[0070] If the vehicle is in a steady-state driving condition, the same target braking torque is calculated and distributed to the wheel ends (the inner wheels of the front and rear wheels) to reduce the vehicle speed in order to maintain the vehicle body posture adjustment.

[0071] like Figure 3 As shown, the present invention provides an active control system for vehicle steering, comprising:

[0072] A front wheel sideslip angle acquisition module, used for acquiring a first front wheel sideslip angle in a rectangular coordinate system of a vehicle body and a second front wheel sideslip angle in a rectangular coordinate system of a front wheel when the vehicle is in an understeering state;

[0073] A vehicle understeering degree coefficient determination module, used for determining the vehicle understeering degree coefficient according to the first front wheel sideslip angle and the second front wheel sideslip angle;

[0074] A vehicle driving condition determination module, used for determining the vehicle driving condition according to the vehicle understeering degree coefficient;

[0075] The active control module is used to adjust the braking torque of the inner wheels of the front and rear wheels, or the braking torque of the rear axle through the vehicle understeering degree coefficient according to the vehicle driving condition.

[0076] Optionally, the front wheel sideslip angle acquisition module is specifically used for:

[0077] When the vehicle is in understeering, the first front wheel slip angle in the rectangular coordinate system of the vehicle body and the second front wheel slip angle in the rectangular coordinate system of the front wheel are obtained. The formula is as follows:

[0078]

[0079] Among them, β So V is the first front wheel side slip angle in the rectangular coordinate system of the vehicle body; yo V is the y-direction speed of the front wheel in the rectangular coordinate system of the vehicle body;xo is the speed of the front wheel in the x direction in the rectangular coordinate system of the vehicle body, β So’ V is the second front wheel side slip angle in the front wheel rectangular coordinate system; yo’ V is the speed of the front wheel in the y direction in the front wheel rectangular coordinate system; xo’ is the speed of the front wheel in the x direction at right angles to the front wheel.

[0080] Optionally, the vehicle understeering degree coefficient determination module is specifically used to:

[0081] The absolute value of the difference between the first front wheel sideslip angle and the second front wheel sideslip angle is used as the third front wheel sideslip angle under vehicle understeering;

[0082] The product of the third front wheel sideslip angle and the first coefficient is used as the vehicle understeering degree coefficient; wherein the first coefficient takes a first preset value according to different vehicle models.

[0083] Optionally, the vehicle driving condition includes a vehicle steady-state driving condition;

[0084] The active control module is specifically used for:

[0085] When the vehicle driving condition is a steady-state driving condition, the braking torque of the inner wheels of the front and rear wheels is adjusted according to the current vehicle speed, the second coefficient, and the vehicle understeer degree coefficient; wherein the second coefficient takes a second preset value according to different vehicle models.

[0086] Optionally, the vehicle driving condition further includes an extreme vehicle driving condition;

[0087] The active control module is specifically used for:

[0088] When the vehicle driving condition is an extreme vehicle driving condition, the braking torque of the rear axle is adjusted according to the current vehicle speed, the third coefficient, and the vehicle understeering degree coefficient; wherein the third coefficient takes a third preset value according to different vehicle models.

[0089] Optionally, the vehicle driving condition further includes a vehicle stable driving condition;

[0090] The active control module is specifically used for:

[0091] If the vehicle is in a stable driving condition, the vehicle steering is controlled by the body stability system.

[0092] Optionally, the front wheel sideslip angle acquisition module is further used for:

[0093] When the vehicle is turning, if the actual yaw rate collected by the vehicle sensor is less than the expected yaw rate, it is determined that the vehicle is understeering.

[0094] An embodiment of the present invention also provides a computing device, including a memory, a manager, and a program stored in the memory and running on the manager. When the manager executes the program, it implements part or all of the steps of the above-mentioned active control method for vehicle steering.

[0095] Among them, the computing device can be a computer, and correspondingly, its program is computer software. The above-mentioned parameters and steps in the computing device of the present invention can refer to the parameters and steps in the embodiment of an active control method for vehicle steering mentioned above, and will not be repeated here.

[0096] Those skilled in the art know that the present invention can be implemented as a system, method or computer program product. Therefore, the present disclosure can be specifically implemented in the following forms, namely: it can be complete hardware, it can be complete software (including firmware, resident software, microcode, etc.), or it can be a combination of hardware and software, generally referred to as "circuit", "module" or "system" herein. In addition, in some embodiments, the present invention can also be implemented in the form of a computer program product in one or more computer-readable media, and the computer-readable medium contains computer-readable program code. Computer-readable storage media can be, for example, but not limited to - electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or devices, or any combination of the above.

[0097] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0098] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for active control of vehicle steering, characterized in that: include: When the vehicle is in understeering, obtaining a first front wheel sideslip angle in a rectangular coordinate system of the vehicle body and a second front wheel sideslip angle in a rectangular coordinate system of the front wheels; determining a vehicle understeering degree coefficient according to the first front wheel sideslip angle and the second front wheel sideslip angle; Determining a vehicle driving condition according to the vehicle understeering degree coefficient; According to the vehicle's driving conditions, the braking torque of the inner wheels of the front and rear wheels, or the braking torque of the rear axle is adjusted by the vehicle's understeering degree coefficient.

2. The method according to claim 1, characterized in that When the vehicle is in understeering, the first front wheel sideslip angle in the rectangular coordinate system of the vehicle body and the second front wheel sideslip angle in the rectangular coordinate system of the front wheel are obtained, and the formula is as follows: Among them, β So V is the first front wheel side slip angle in the rectangular coordinate system of the vehicle body; yo V is the y-direction speed of the front wheel in the rectangular coordinate system of the vehicle body; xo is the speed of the front wheel in the x direction in the rectangular coordinate system of the vehicle body, β So’ V is the second front wheel side slip angle in the front wheel rectangular coordinate system; yo’ V is the speed of the front wheel in the y direction in the front wheel rectangular coordinate system; xo’ is the speed of the front wheel in the x direction at right angles to the front wheel.

3. The method according to claim 1, characterized in that Determining a vehicle understeering degree coefficient according to the first front wheel sideslip angle and the second front wheel sideslip angle includes: taking the absolute value of the difference between the first front wheel sideslip angle and the second front wheel sideslip angle as a third front wheel sideslip angle under vehicle understeering; The product of the third front wheel sideslip angle and the first coefficient is used as the vehicle understeering degree coefficient; wherein the first coefficient takes a first preset value according to different vehicle models.

4. The method according to claim 1, characterized in that: The vehicle driving condition includes a vehicle steady-state driving condition; According to the vehicle's driving conditions, the braking torque of the inner wheels of the front and rear wheels, or the braking torque of the rear axle, is adjusted by the vehicle's understeering coefficient, including: When the vehicle driving condition is a steady-state driving condition, the braking torque of the inner wheels of the front and rear wheels is adjusted according to the current vehicle speed, the second coefficient, and the vehicle understeer degree coefficient; wherein the second coefficient takes a second preset value according to different vehicle models.

5. The method according to claim 4, characterized in that The vehicle driving conditions also include extreme vehicle driving conditions; According to the vehicle's driving conditions, the braking torque of the inner wheels of the front and rear wheels, or the braking torque of the rear axle, is adjusted by the vehicle's understeering coefficient, including: When the vehicle driving condition is an extreme vehicle driving condition, the braking torque of the rear axle is adjusted according to the current vehicle speed, the third coefficient, and the vehicle understeering degree coefficient; wherein the third coefficient takes a third preset value according to different vehicle models.

6. The method according to claim 5, characterized in that The vehicle driving condition also includes a vehicle stable driving condition; According to the vehicle driving condition, the braking torque of the inner wheels of the front and rear wheels or the braking torque of the rear axle is adjusted by the vehicle understeering degree coefficient, and also includes: If the vehicle is in a stable driving condition, the vehicle steering is controlled by the body stability system.

7. The method according to any one of claims 1 to 6, characterized in that: Also includes: When the vehicle is turning, if the actual yaw rate collected by the vehicle sensor is less than the expected yaw rate, it is determined that the vehicle is understeering.

8. An active control system for vehicle steering, characterized in that: include: A front wheel sideslip angle acquisition module, used for acquiring a first front wheel sideslip angle in a rectangular coordinate system of a vehicle body and a second front wheel sideslip angle in a rectangular coordinate system of a front wheel when the vehicle is in an understeering state; a vehicle understeering degree coefficient determining module, configured to determine a vehicle understeering degree coefficient according to the first front wheel sideslip angle and the second front wheel sideslip angle; A vehicle driving condition determination module, used for determining the vehicle driving condition according to the vehicle understeering degree coefficient; The active control module is used to adjust the braking torque of the inner wheels of the front and rear wheels, or the braking torque of the rear axle through the vehicle understeering degree coefficient according to the vehicle driving condition.

9. A computing device comprising a memory, a processor, and a program stored in the memory and running on the processor, characterized in that: When the processor executes the program, the steps of the active control method for vehicle steering as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that: Instructions are stored in the computer-readable storage medium. When the instructions are executed on the terminal device, the terminal device executes the steps of the active control method for vehicle steering as described in any one of claims 1 to 7.

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