Vehicle turning control device and vehicle

Abstract

An embodiment of the present invention provides a vehicle turning control device and a vehicle, comprising: a steering control device for providing a steering assist force, a vehicle braking control device for providing a braking force; an ECU control unit for obtaining a vehicle sideslip angle and, based on the vehicle sideslip angle, controlling the steering control device to adjust the steering assist force and / or controlling the vehicle braking control device to adjust the braking force, thereby reducing abnormal wear of tires and brake pads.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and in particular to a vehicle turning control device and a vehicle. Background Art

[0002] Conventional technology uses the steering direction of the steering wheel to improve the rotational characteristics of the braking force generated by the rear inner rotating wheel relative to the direction of travel. Various sensors measure the axle weight (load) of each wheel to calculate the slip angle and slip ratio. Based on these results, the magnitude of the braking force applied to the rear inner rotating wheel and the magnitude of the driving force applied to the front wheels are determined. The brakes corresponding to the rear inner rotating wheel are then controlled to apply the appropriate braking force to the rear inner rotating wheel, thereby controlling the vehicle's cornering. However, because the road's coefficient of friction is not taken into account, abnormal tire and brake pad wear cannot be reduced. Summary of the Invention

[0003] In view of the above problems, embodiments of the present invention are proposed to provide a vehicle turning control device and a vehicle that overcome the above problems or at least partially solve the above problems.

[0004] In order to solve the above problems, an embodiment of the present invention discloses a vehicle turning control device, comprising:

[0005] Steering control device, used to provide steering assist force,

[0006] Vehicle brake control device, used to provide braking force;

[0007] The ECU control unit is used to obtain the vehicle sideslip angle and, based on the vehicle sideslip angle, control the steering control device to adjust the steering assist force and / or control the vehicle brake control device to adjust the braking force.

[0008] Optionally, the ECU control unit is specifically configured to calculate a tire slip angle based on the vehicle sideslip angle calculated by the driving state detection unit; and determine whether vehicle turning control is allowed based on the tire slip angle.

[0009] Optionally, the ECU control unit is specifically configured to prohibit vehicle turning control when a tire slip angle of a front wheel rotating an outer ring or a rear wheel rotating an inner ring exceeds a limit threshold;

[0010] The vehicle turning prohibition control includes controlling the vehicle braking control device to maintain the braking force, and / or controlling the steering control device to maintain or reduce the steering assist force, and / or controlling the assist force in the direction of turning back the steering wheel.

[0011] Optionally, the ECU control unit is specifically used to control the rotating inner ring of the rear wheel by applying corresponding braking force according to the tire slip angle of the rotating outer ring of the front wheel or the rotating inner ring of the rear wheel when the tire slip angle of the rotating outer ring of the front wheel or the rotating inner ring of the rear wheel is lower than a limit threshold.

[0012] Optionally, the ECU control unit is further configured to obtain a road friction coefficient and adjust a limit threshold of a vehicle sideslip angle according to the road friction coefficient.

[0013] Optionally, the ECU control unit is specifically configured to, when the road friction coefficient is less than or equal to a first preset threshold value, maintain a limit threshold value of the vehicle sideslip angle unchanged as the road friction coefficient increases; and, when the road friction coefficient is greater than the first preset threshold value and less than or equal to a second preset threshold value, adjust the limit threshold value of the vehicle sideslip angle to increase accordingly as the road friction coefficient increases; and when the limit threshold value of the vehicle sideslip angle reaches a preset limit threshold value, maintain the limit threshold value of the vehicle sideslip angle unchanged as the friction coefficient increases.

[0014] An embodiment of the present invention further discloses a vehicle, comprising: a vehicle turning control device as described above.

[0015] The embodiments of the present invention include the following advantages: a steering control device for providing steering assist force, a vehicle braking control device for providing braking force; an ECU control unit for obtaining a vehicle sideslip angle and, based on the vehicle sideslip angle, controlling the steering control device to adjust the steering assist force and / or controlling the vehicle braking control device to adjust the braking force, thereby reducing abnormal wear of tires and brake pads. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a structural diagram of a vehicle turning control device provided by an embodiment of the present invention;

[0017] Figure 2 is a structural diagram of a vehicle provided by an embodiment of the present invention;

[0018] Figure 3 This is a flowchart of the steps of a vehicle turning control method provided by an embodiment of the present invention;

[0019] Figure 4 A diagram illustrating the relationship between a vehicle sideslip angle and a tire sliding angle is provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] In the previous system that uses braking force to improve the cornering characteristics of the vehicle, abnormal wear of the tires and brake pads occurred because the friction coefficient of the road was not taken into account. There was no device that took the friction coefficient of the road into consideration to avoid abnormal wear of the tires and brake pads.

[0022] One of the core concepts of an embodiment of the present invention is to obtain the vehicle sideslip angle through the ECU control unit, and control the steering control device to adjust the steering assist force and / or control the vehicle braking control device to adjust the braking force according to the vehicle sideslip angle, thereby reducing abnormal wear of the tires and abnormal wear of the brake pads.

[0023] Reference Figure 1 , shows a structural diagram of a vehicle turning control device provided by an embodiment of the present invention, including: a steering control device 101, used to provide steering assist force; a vehicle braking control device 102, used to provide braking force; an ECU control unit 103, used to obtain a vehicle sideslip angle and, based on the vehicle sideslip angle, control the steering control device to adjust the steering assist force and / or control the vehicle braking control device to adjust the braking force.

[0024] In an embodiment of the present invention, the vehicle turning control device may further be provided with an anti-skid device (ESC), which may enable the vehicle braking control device 102 to prevent the wheels of the vehicle from slipping when driving or braking, thereby maintaining the stability of the vehicle when turning and improving the handling stability of the vehicle, and may enable the steering control device 101 to further prevent the vehicle from shaking and maintain the stability of the vehicle during the process of steering control of the vehicle.

[0025] As an example, during vehicle turning control, the ECU control unit 103 can obtain the vehicle sideslip angle, and control the steering control device to adjust the steering assist force and / or control the vehicle braking control device to adjust the braking force according to the vehicle sideslip angle.

[0026] As an example, Figure 2The illustrated diagram shows a vehicle structure provided by an embodiment of the present invention. During vehicle turning control, the vehicle speed can be acquired via a vehicle speed sensor 104. When the vehicle speed is below a preset speed and the steering wheel angle is set to a preset angle, the ECU control unit 103 can control the steering control device to perform vehicle turning control. For example, steering wheel rotation generates torque, and the torque sensor transmits the torque sensing signal to the ECU control unit 103. The ECU control unit 103 generates a control signal and transmits it to the motor. The motor operates according to the control signal, which is transmitted to the rack and gear mechanism via the warm gear, thereby controlling the steering wheel through the rack and gear mechanism. During the auxiliary force steering control process, the auxiliary force can be maintained or reduced, or the steering wheel angle can be returned for control based on the calculated control value of the steering device control variable. Furthermore, the braking force control device can be controlled to perform braking force control, calculating the wheel cylinder pressure (braking force) and applying it to the inner wheel to brake the inner wheel. For example, if the vehicle speed is below the preset speed, the brake fluid pressure is controlled to decrease, thereby reducing the braking force.

[0027] In one embodiment of the present invention, the ECU control unit is specifically used to calculate the tire slip angle based on the vehicle sideslip angle calculated by the driving state detection unit; and determine whether vehicle turning control is allowed based on the tire slip angle.

[0028] In the embodiment of the present invention, the driving state of the vehicle may include a braking state in which a braking unit applies braking force to a wheel, a steering state in which a driver operates the steering wheel to change a steering wheel angle, and a normal state that is not any of the above states. The ECU control unit 103 may obtain any of the vehicle states: the braking state, the steering state, or the normal state.

[0029] Exemplarily, the vehicle braking control device 102 may include a braking unit and a driving state detection unit. During the vehicle braking control process, the driving state of the vehicle may be detected by the driving state detection unit, and the braking unit performs braking control on each wheel according to the vehicle driving state.

[0030] As an example, Figure 2 As shown in the structural diagram of a vehicle provided by an embodiment of the present invention, the ECU control unit 103 can obtain corresponding detection values ​​such as vehicle body speed V, wheel speed V1, yaw rate ψ, lateral acceleration Yg, etc. from the vehicle body speed sensor 104, wheel speed sensor 105, yaw rate sensor 106, and lateral G sensor 107 respectively; the vehicle's sideslip angle β can be calculated based on the detection values, and then the sliding angle of each tire can be calculated based on the vehicle's sideslip angle. Based on the tire sliding angle, it can be determined whether vehicle turning control is allowed.

[0031] In one embodiment of the present invention, the ECU control unit is specifically used to prohibit vehicle turning control when the tire slip angle of the outer ring rotating in front of the wheel or the inner ring rotating behind the wheel exceeds a limit threshold; wherein, prohibiting vehicle turning control includes controlling the vehicle braking control device to maintain braking force, and / or controlling the steering control device to maintain or reduce steering assist force, and / or controlling the assist force in the direction of turning back the steering wheel.

[0032] As an example, the ECU control unit 103 can calculate the sliding angle of each tire based on the vehicle sideslip angle β calculated by the driving state detection unit, and can determine whether vehicle turning control is allowed based on the tire sliding angle.

[0033] As an example, the ECU control unit 103 can further determine whether to continue vehicle turning control based on the slip angle of each tire. If the tire slip angle is greater than a threshold, vehicle turning control can be prohibited. For example, the braking control device can be controlled to maintain the braking force, and / or the steering device can be controlled to maintain or reduce the steering assist force, and / or the assist force can be controlled in the direction of turning the steering wheel back.

[0034] In one embodiment of the present invention, the ECU control unit is specifically used to control the corresponding braking force on the front rotating outer ring of the wheel or the rear rotating inner ring of the wheel according to the tire slip angle of the rear rotating inner ring of the wheel when the tire slip angle of the front rotating outer ring of the wheel or the rear rotating inner ring of the wheel is lower than a limit threshold.

[0035] As an example, if the sliding angle of the vehicle tire is less than or equal to a limit threshold during the turning process, the vehicle control device can calculate the amount of control over the wheel that needs to be adjusted based on the size of the tire sliding angle. For example, based on the tire sliding angle of the front rotating outer ring of the wheel or the rear rotating inner ring of the wheel, the brake hydraulic pressure of the vehicle control device is adjusted to apply corresponding braking force to the rear rotating inner ring of the wheel for control.

[0036] As an example, the vehicle control device can separately control different wheels of the same vehicle, and each wheel is independently controlled. Those skilled in the art can operate and control the wheels according to actual conditions, and the embodiments of the present invention do not limit this.

[0037] In one embodiment of the present invention, the ECU control unit is further configured to obtain a road friction coefficient and adjust a limit threshold of a vehicle sideslip angle according to the road friction coefficient.

[0038] For example, the correspondence between the road friction coefficient and the limit threshold of the vehicle sideslip angle can be pre-set, and the ECU control unit can adjust the limit threshold of the vehicle sideslip angle according to the correspondence between the road friction coefficient and the limit threshold of the vehicle sideslip angle.

[0039] As an example, the ECU control unit 103 can obtain the vehicle body speed V and the wheel speed V1 from the vehicle body speed sensor 104 and the wheel speed sensor 105 in the driving state detection unit, calculate the slip rate λ based on the vehicle body speed V and the wheel speed V1, and determine the road friction coefficient based on the characteristic curve formed by the braking force and the slip rate.

[0040] As an example, ECU control unit 103 may estimate and calculate the road friction coefficient μ corresponding to wheel slip ratio λ based on a λ-μ characteristic curve that shows the relationship between the road friction coefficient μ and the wheel slip ratio. The λ-μ characteristic curve has a variable characteristic, namely, as the wheel slip ratio λ increases, the road friction coefficient μ increases. If the wheel slip ratio λ reaches or exceeds a predetermined slip ratio, the road friction coefficient μ gradually decreases as the wheel slip ratio λ increases.

[0041] The corresponding relationship between the slip rate λ and the road friction coefficient μ can be pre-set. Different vehicle models form different λ-μ characteristic curves. Those skilled in the art can set them according to actual conditions, and the embodiments of the present invention do not limit this.

[0042] In addition, it is well known to those skilled in the art that determining the road friction coefficient based on the characteristic curve formed by the braking force and the slip rate is only an example of an embodiment of the present invention. Those skilled in the art can also determine the road friction coefficient in other ways, and the embodiment of the present invention does not limit this.

[0043] In one embodiment of the present invention, the ECU control unit is specifically configured to, when the road friction coefficient is less than or equal to a first preset threshold value, maintain the limit threshold value of the vehicle sideslip angle unchanged as the road friction coefficient increases; when the road friction coefficient is greater than the first preset threshold value and less than or equal to a second preset threshold value, adjust the limit threshold value of the vehicle sideslip angle to increase accordingly as the road friction coefficient increases; and when the limit threshold value of the vehicle sideslip angle reaches the preset limit threshold value, maintain the limit threshold value of the vehicle sideslip angle unchanged as the friction coefficient increases.

[0044] As an example, a correspondence between the road friction coefficient and a threshold value for the vehicle's sideslip angle can be preset. If the road friction coefficient is less than or equal to a first preset threshold, the threshold value for the vehicle's sideslip angle remains unchanged as the road friction coefficient increases. If the road friction coefficient is greater than the first preset threshold and less than or equal to a second preset threshold, the threshold value for the vehicle's sideslip angle increases as the road friction coefficient increases. If the road friction coefficient is greater than the second preset threshold, the threshold value for the vehicle's sideslip angle cannot increase further after reaching the preset threshold value and remains unchanged as the road friction coefficient increases.

[0045] In an embodiment of the present invention, a vehicle turning control device includes a vehicle braking control device, a steering control device and an ECU control unit. The ECU control unit controls the vehicle sideslip angle and controls the steering control device to adjust the steering assist force and / or controls the vehicle braking control device to adjust the braking force according to the vehicle sideslip angle, thereby reducing abnormal wear of tires and brake pads.

[0046] Reference Figure 3 , shows a flowchart of a vehicle turning control method provided by an embodiment of the present invention, the method may specifically include the following steps:

[0047] The process begins:

[0048] S1, obtain the detection values ​​of each vehicle sensor;

[0049] For example, the ECU control unit 103 can obtain corresponding detection values ​​such as vehicle body speed V, wheel speed V1, yaw rate ψ, lateral acceleration Yg, etc. from the vehicle body speed sensor 104, wheel speed sensor 105, yaw rate sensor 106, and lateral G sensor 107 respectively.

[0050] S2, the driving state detection unit calculates the vehicle driving state according to the detection values ​​of each sensor;

[0051] It should be noted that the vehicle driving state herein may include a braking state in which the braking system of the vehicle control device applies braking force to the wheels, a steering state in which the driver operates the steering wheel to change the steering wheel angle θ, and a normal state other than any of the above. In other words, the vehicle driving state may be any of the braking state, the steering state, or the normal state, and this is not limited in the present embodiment.

[0052] S3, calculates the sideslip angle of the vehicle;

[0053] In a specific implementation, the vehicle slip angle β may be obtained based on the relationship between the detection value Yg of the lateral G sensor 107 , the detection value V of the vehicle body speed sensor 104 , and the detection value ψ of the yaw rate sensor 106 .

[0054] For example: dβ / dt=Yg / V-ψ

[0055] It should be noted that, regarding the removal of the integral error, it can be set to 0 when the lateral acceleration and yaw rate are 0.

[0056] S4, calculates the tire slip angle of the vehicle;

[0057] For example, the vehicle can be simplified into a two-wheel model, and the sliding angle of the tires is calculated according to the following formula:

[0058]

[0059]

[0060] like Figure 4 The embodiment of the present invention shown in FIG. 1 provides a diagram for illustrating the relationship between a vehicle side slip angle and a tire slip angle, wherein: and are the front and rear wheel slip angles of the vehicle respectively; is the front wheel steering angle, and is the toe angle of the rear wheels; V is the vehicle body speed; β is the vehicle sideslip angle; and are the distances from the vehicle's center of mass to the front and rear axles respectively; ψ is the vehicle's yaw angular velocity (also known as the yaw rate).

[0061] For example, a characteristic value of the vehicle's sideslip angle β can be determined based on a characteristic curve formed by the vehicle's sideslip angle β and the vehicle's yaw rate ψ. During vehicle stability control, the vehicle's sideslip angle β can be limited to within the characteristic value range, thereby preventing the vehicle from slipping in emergency situations while ensuring that the gain in the vehicle's yaw rate ψ remains within a reasonable range. The control unit controls the vehicle before the characteristic value is reached to ensure that the wheels can brake or drive normally and generate sufficient additional yaw torque to maintain vehicle stability.

[0062] In addition, the corresponding relationship of the β-ψ characteristic curve can be preset. Different vehicle models form different β-ψ characteristic curves. Those skilled in the art can set them according to actual conditions, and the embodiment of the present invention does not limit them here.

[0063] S5, determining whether to allow or prohibit vehicle turning control;

[0064] For example, whether to perform vehicle turning control can be determined based on the vehicle speed and the steering wheel angle; for example, when the vehicle speed is lower than a preset speed and the steering wheel angle is greater than a preset angle, the ECU control unit controls the steering control device to perform vehicle turning control, or controls the vehicle braking control device to perform braking control; otherwise, control is prohibited, and the control amount of the steering wheel turning control is reset to "0".

[0065] S6, determining whether the vehicle turning control continues;

[0066] For example, if the tire slip angle of the front outer wheel or the rear inner wheel exceeds a preset threshold, tire and pad wear will increase. Therefore, if the slip angle of either or both wheels exceeds a certain value, control is disabled. If the slip angle of each wheel is below the threshold, braking force can be applied to the rear inner wheel based on the tire slip angle.

[0067] S7, if the vehicle turning control is determined to continue, the braking force required for control is calculated;

[0068] For example, the corresponding braking force calculation value can be obtained based on the correspondence between the steering wheel angle and the braking force during the vehicle turning control process, and the calculated braking force value can be converted into a wheel cylinder pressure value, which can be applied to the wheel for braking through the wheel cylinder pressure (i.e., braking force).

[0069] S8, calculating the limit threshold of the vehicle sideslip angle;

[0070] S9: Adjusts the steering assist force and braking force according to the vehicle's sideslip angle limit threshold;

[0071] For example, during vehicle turning control, if the vehicle sideslip angle reaches a limit threshold, the steering assist force or the braking force may be maintained or the steering wheel steering angle may be assisted in the return direction.

[0072] S10, applying the calculated braking force to the rear inner ring of the tire;

[0073] S11, if the vehicle turning control is determined not to continue, prohibiting the control;

[0074] The process ends.

[0075] It should be noted that for the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should be aware that the embodiments of the present invention are not limited by the order of the actions described, because according to the embodiments of the present invention, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in this specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present invention.

[0076] An embodiment of the present invention further provides a vehicle, comprising: the vehicle turning control device as described in the above embodiment.

[0077] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0078] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, apparatus, or computer program products. Thus, embodiments of the present invention may take the form of a fully hardware embodiment, a fully software embodiment, or an embodiment combining software and hardware. Furthermore, embodiments of the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0079] The embodiments of the present invention are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0080] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0081] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device so that a series of operating steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable terminal device to implement the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0082] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0083] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or terminal device that includes the element.

[0084] The vehicle turning control device and a vehicle provided by the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A vehicle turning control device, characterized in that: include: Steering control device, used to provide steering assist force, Vehicle brake control device, used to provide braking force; an ECU control unit, configured to obtain a sideslip angle of the vehicle and, based on the sideslip angle of the vehicle, control the steering control device to adjust the steering assist force and / or control the vehicle brake control device to adjust the braking force; The ECU control unit is further configured to calculate a tire slip angle based on the vehicle sideslip angle calculated by the driving state detection unit; and determine whether vehicle turning control is permitted based on the tire slip angle. The ECU control unit is further configured to prohibit vehicle turning control when the tire slip angle of the outer rotating wheel in front or the inner rotating wheel in rear exceeds a limit threshold; Wherein, the vehicle turning prohibition control includes: The vehicle brake control device is controlled to maintain the braking force, the steering control device is controlled to maintain the steering assist force, and the assist force is controlled to return to the steering angle of the steering wheel in the direction of turning the steering wheel back.

2. The vehicle turning control device according to claim 1, characterized in that: The ECU control unit is specifically used to control the rear rotating inner wheel by applying corresponding braking force according to the tire slip angle of the front rotating outer wheel or the rear rotating inner wheel when the tire slip angle of the front rotating outer wheel or the rear rotating inner wheel is lower than a limit threshold.

3. The vehicle turning control device according to claim 1 or 2, characterized in that: The ECU control unit is further configured to obtain a road friction coefficient and adjust a vehicle sideslip angle limit threshold based on the road friction coefficient.

4. The vehicle turning control device according to claim 3, characterized in that: The ECU control unit is specifically configured to adjust the limit threshold of the vehicle sideslip angle as the road friction coefficient increases when the road friction coefficient is less than or equal to a first preset threshold; and to increase the limit threshold of the vehicle sideslip angle accordingly as the road friction coefficient increases when the road friction coefficient is greater than the first preset threshold and less than or equal to a second preset threshold; and when the limit threshold of the vehicle sideslip angle reaches the preset limit threshold, maintain the limit threshold of the vehicle sideslip angle unchanged as the friction coefficient increases.

5. A vehicle, characterized in that: include: The vehicle turning control device according to any one of claims 1 to 4.

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