Four-wheel drive clutch control method and system

Abstract

The invention discloses a four-wheel-drive clutch control method and system, and belongs to the technical field of clutch control. The method comprises the steps that the position of a KP point of a four-wheel-drive clutch is obtained; according to the four-wheel-drive clutch KP point position, the four-wheel-drive clutch abrasion state is judged; when the abrasion state of the four-wheel-drive clutch is serious abrasion, a four-wheel-drive mode control instruction is obtained; when the four-wheel-drive mode control instruction is a four-wheel-drive stopping mode, the vehicle is controlled to stop the four-wheel-drive mode; and when the four-wheel-drive mode control instruction is to keep the four-wheel-drive mode, the vehicle is controlled to keep the four-wheel-drive mode, and the output torque of the clutch is reduced.

Description

Technical Field

[0001] This application relates to the technical field of clutch control, and particularly to a four-wheel drive clutch control method and system. Background Art

[0002] The statements in this part merely provide background technical information related to the present invention and do not necessarily constitute prior art.

[0003] The self-learning technology of the clutch semi-engagement point (KissPoint, KP point) is an important part of the vehicle power transmission system. It involves the accuracy and consistency of clutch control and is directly related to the handling stability and power performance of the vehicle.

[0004] Through the position of the clutch KP point, the wear state of the clutch can be reflected to a certain extent, and the wear state of the clutch affects the four-wheel drive ability of the vehicle, thereby affecting vehicle safety. However, currently, after it is determined that the clutch is worn based on the KP point position, only a reminder message is sent, and the mode state of the clutch is not automatically controlled.

[0005] When the driver ignores the reminder message due to clutch wear and continues to drive the vehicle in the four-wheel drive mode, the four-wheel drive ability of the vehicle is weakened, thus affecting the driving safety of the vehicle. Summary of the Invention

[0006] In view of this, the purpose of this application is to provide a four-wheel drive clutch control method and system, which can adaptively control the operation mode of the vehicle according to the wear state of the clutch to ensure vehicle driving safety.

[0007] This application mainly includes the following aspects:

[0008] In the first aspect, an embodiment of this application provides a four-wheel drive clutch control method, including:

[0009] Obtain the position of the four-wheel drive clutch KP point;

[0010] Determine the wear state of the four-wheel drive clutch according to the position of the four-wheel drive clutch KP point;

[0011] When the wear state of the four-wheel drive clutch is severe wear, obtain the four-wheel drive mode operation instruction;

[0012] When the four-wheel drive mode operation instruction is to stop the four-wheel drive mode, control the vehicle to stop the four-wheel drive mode;

[0013] When the four-wheel drive mode operation instruction is to maintain the four-wheel drive mode, control the vehicle to maintain the four-wheel drive mode and reduce the clutch output torque.

[0014] Further, when the wear state of the four-wheel drive clutch exceeds the limit, the vehicle is controlled to stop the four-wheel drive mode;

[0015] When the wear state of the four-wheel drive clutch is not worn, the vehicle is controlled to maintain the four-wheel drive mode.

[0016] Further, when the KP point position is greater than or equal to the first set position threshold, it is determined that the wear state of the four-wheel drive clutch exceeds the limit;

[0017] When the KP point position is less than the first set position threshold and greater than or equal to the second set position threshold, it is determined that the wear state of the four-wheel drive clutch is severely worn;

[0018] When the KP point position is less than the second set position threshold, it is determined that the wear state of the four-wheel drive clutch is not worn.

[0019] Further, when the wear state of the four-wheel drive clutch is severely worn, a reminder message of whether to stop the four-wheel drive mode is sent.

[0020] Further, when the four-wheel drive mode operation instruction is to maintain the four-wheel drive mode, the output torque of the clutch is obtained;

[0021] According to the KP point position of the four-wheel drive clutch, the torque limit coefficient is determined;

[0022] The obtained output torque of the clutch is multiplied by the torque limit coefficient to obtain the target value of the output torque of the four-wheel drive clutch;

[0023] The output torque of the four-wheel drive clutch is controlled to be reduced to the target value of the output torque of the four-wheel drive clutch.

[0024] Further, the KP point position and the torque limit coefficient are linearly negatively correlated.

[0025] In a second aspect, an embodiment of the present application further provides a four-wheel drive clutch control system, including:

[0026] A KP point position acquisition unit for acquiring the KP point position of the four-wheel drive clutch;

[0027] A clutch wear state determination unit for determining the wear state of the four-wheel drive clutch according to the KP point position of the four-wheel drive clutch;

[0028] A four-wheel drive mode operation instruction acquisition unit for acquiring the four-wheel drive mode operation instruction when the wear state of the four-wheel drive clutch is severely worn;

[0029] A four-wheel drive mode control unit for controlling the vehicle to stop the four-wheel drive mode when the four-wheel drive mode operation instruction is to stop the four-wheel drive mode; and for controlling the vehicle to maintain the four-wheel drive mode and reducing the output torque of the clutch when the four-wheel drive mode operation instruction is to maintain the four-wheel drive mode.

[0030] In a third aspect, an embodiment of the present application further provides a computer device, which includes:

[0031] a processor, adapted to execute a computer program;

[0032] a computer-readable storage medium storing a computer program, which when executed by the processor, implements a four-wheel drive clutch control method provided in the first aspect.

[0033] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium storing a computer program, and the computer program is adapted to be loaded and executed by a processor to implement a four-wheel drive clutch control method proposed in the first aspect.

[0034] In a fifth aspect, an embodiment of the present application further provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, it implements a four-wheel drive clutch control method proposed in the first aspect.

[0035] A four-wheel drive clutch control method and system provided by an embodiment of the present application. The method first determines the wear state of the four-wheel drive clutch according to the position of the KP point of the four-wheel drive clutch; then, controls the four-wheel drive mode of the vehicle according to the wear state of the clutch. Specifically, if the wear state of the four-wheel drive clutch is severe wear and the received driver's four-wheel drive mode operation instruction is to stop the four-wheel drive mode, the vehicle is controlled to stop the four-wheel drive mode; if the wear state of the four-wheel drive clutch is severe wear, but the received driver's four-wheel drive mode operation instruction is to maintain the four-wheel drive mode, the vehicle is controlled to maintain the four-wheel drive mode, but the output torque of the clutch is controlled to decrease, thereby reducing the wear of the clutch and extending the duration of the four-wheel drive, and ensuring the driving safety of the vehicle to a certain extent.

[0036] To make the above objects, features, and advantages of the present application more obvious and understandable, the following specifically gives preferred embodiments and, in conjunction with the accompanying drawings, makes a detailed description as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] To more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0038] Figure 1 It is a flowchart of a four-wheel drive clutch control method provided by an embodiment of the present application;

[0039] Figure 2Schematic diagram of whether to stop the four-wheel drive mode reminder information provided by the embodiments of the present application;

[0040] Figure 3 Clutch status confirmation reminder information provided by the embodiments of the present application;

[0041] Figure 4 Schematic diagram of signal flow provided by the embodiments of the present application.

[0042] Through the above-mentioned drawings, specific embodiments of the present application have been shown, and more detailed descriptions will be given later. These drawings and text descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. Detailed implementation manners

[0043] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Usually, the components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the present application to be protected, but only represents the selected embodiments of the present application. Based on the embodiments of the present application, every other embodiment obtained by those skilled in the art without creative efforts belongs to the scope of protection of the present application.

[0044] First, the applicable application scenarios and the architecture of the applicable system of the present application are introduced. The present application can be applied to the vehicle clutch scenario.

[0045] When the clutch wears, it will have an adverse impact on the four-wheel drive ability of the vehicle. At this time, if the vehicle continues to be in the four-wheel drive mode, the driving safety of the vehicle will be affected due to the weakened four-wheel drive ability of the vehicle.

[0046] The architecture of the applicable system of the present application includes a four-wheel drive controller, a four-wheel drive clutch, a motor, and a human-machine interaction module; the four-wheel drive controller is used to control the rotation of the motor, the rotation of the motor drives the gear in the clutch to rotate, and finally pushes the clutch pressure plate to move. The four-wheel drive controller is also used to control the separation and engagement of the clutch, so as to switch between the four-wheel drive mode and the two-wheel drive mode of the vehicle; the human-machine interaction module is used to display various alarm messages and receive the four-wheel drive mode operation instruction IHU_bCluUseChoise.

[0047] After introducing the structure and application scenarios of the system involved in the embodiments of the present application, to make the technical solutions and advantages of the present application clearer, the following will further describe the embodiments of the present application in detail with reference to the drawings.

[0048] An embodiment of the present application provides a four-wheel drive clutch control method. After determining the wear state of the clutch based on the KP point position of the clutch, the clutch is automatically controlled according to the wear state of the clutch and in combination with the four-wheel drive mode operation instruction issued by the driver to ensure the driving safety of the vehicle.

[0049] As Figures 1-4 shown, a four-wheel drive clutch control method provided by an embodiment of the present application includes:

[0050] Obtain the KP point position of the four-wheel drive clutch;

[0051] Determine the wear state of the four-wheel drive clutch according to the KP point position of the four-wheel drive clutch;

[0052] When the wear state of the four-wheel drive clutch is severe wear, obtain the four-wheel drive mode operation instruction;

[0053] When the four-wheel drive mode operation instruction is to stop the four-wheel drive mode, control the vehicle to stop the four-wheel drive mode;

[0054] When the four-wheel drive mode operation instruction is to maintain the four-wheel drive mode, control the vehicle to maintain the four-wheel drive mode and reduce the clutch output torque.

[0055] As the friction plate in the clutch wears, the zero position of the clutch will change. In order to ensure the accuracy of the obtained KP point position of the four-wheel drive clutch and thus accurately judge the wear state of the clutch, in some embodiments, first control the clutch to perform zero position self-learning to obtain the zero position of the clutch; then, control the clutch to perform KP point position learning to obtain the KP point position of the four-wheel drive clutch.

[0056] Specifically, control the motor through the four-wheel drive controller to reverse the gear in the clutch, so that the clutch pressure plate disengages to the motor stall position, record this position, and set this position as the zero position of the clutch.

[0057] After that, control the motor through the four-wheel drive controller to rotate the gear forward, push the clutch pressure plate to the just-engaged position, record this position, and use this position as the KP point position of the clutch.

[0058] As the four-wheel drive clutch is used, the clutch wear becomes heavier and the KP point position gradually increases. In order to effectively control the clutch according to different wear states of the clutch, in some embodiments, judge the wear state of the four-wheel drive clutch through the range where the KP point position of the clutch is located. Specifically:

[0059] When the KP point position is greater than or equal to the first set position threshold, determine that the wear state of the four-wheel drive clutch is excessive wear;

[0060] When the position of the KP point is less than the first set position threshold and greater than or equal to the second set position threshold, it is determined that the wear state of the four-wheel drive clutch is severely worn;

[0061] When the position of the KP point is less than the second set position threshold, it is determined that the wear state of the four-wheel drive clutch is not worn.

[0062] Among them, the first set position threshold and the second set position threshold can be defined according to actual needs. For example, the first set position threshold is set to 2.2, and the second set position threshold is set to 1.8.

[0063] In some embodiments, when the wear state of the four-wheel drive clutch exceeds the limit, the vehicle is controlled to stop the four-wheel drive mode;

[0064] When the wear state of the four-wheel drive clutch is not worn, the vehicle is controlled to maintain the four-wheel drive mode;

[0065] When the wear state of the four-wheel drive clutch is severely worn, a reminder message for whether to stop the four-wheel drive mode is issued, such as Figure 2 shown.

[0066] In some embodiments, when the wear state of the four-wheel drive clutch is severely worn, a reminder message that the four-wheel drive clutch is severely worn and please go to the service station to confirm the state of the four-wheel drive clutch is also issued, such as Figure 3 shown.

[0067] In some embodiments, the reminder message is displayed through the human-machine interaction module, and the human-machine interaction module can also accept the four-wheel drive mode operation instruction issued by the driver.

[0068] Such as Figure 2 shown, when the human-machine interaction module displays the reminder message for whether to stop the four-wheel drive mode, the "Yes" and "No" soft buttons are simultaneously displayed. When the driver selects "Yes", the four-wheel drive mode operation instruction obtained by the four-wheel drive controller is to maintain the four-wheel drive mode; when the driver selects "No", the four-wheel drive mode operation instruction obtained by the four-wheel drive controller is to stop the four-wheel drive mode.

[0069] When the stop four-wheel drive mode instruction is received, the vehicle is controlled to stop the four-wheel drive mode;

[0070] When the maintain four-wheel drive mode instruction is received, the vehicle is controlled to maintain the four-wheel drive mode and reduce the output torque.

[0071] In order to accurately control the clutch output torque in combination with the wear state of the four-wheel drive clutch, in some embodiments, when the four-wheel drive mode operation instruction is to maintain the four-wheel drive mode, the clutch output torque is obtained;

[0072] According to the position of the KP point of the four-wheel drive clutch, the torque limit coefficient is determined;

[0073] Multiply the obtained clutch output torque by a torque limit coefficient to obtain the target value of the four-wheel drive clutch output torque;

[0074] Control the four-wheel drive clutch output torque to decrease to the target value of the four-wheel drive clutch output torque.

[0075] Since the larger the KP point position, the more serious the clutch wear and the weaker the four-wheel drive ability of the vehicle, it is specified that the KP point position is linearly negatively correlated with the torque limit coefficient.

[0076] In some embodiments, look up a table according to the KP point position to determine the torque limit coefficient. When the KP point position changes from the second set position threshold to the first set position threshold, the torque limit coefficient linearly changes from 0.25 to 0.

[0077] A four-wheel drive clutch control method proposed in an embodiment of the present application is applied after the clutch self-learning function is activated.

[0078] As Figure 4 shown, in AWD (all-wheel drive), the BSW bottom-layer software in the BSW sends a clutch self-learning request bsw_bSLReq to the application layer; the four-wheel drive controller receives the actual engine speed Ems_nEngSpd through the CAN line; the four-wheel drive controller also sends a signal indicating serious four-wheel drive clutch wear AWD_bCluWearSer to the human-machine interaction module through the CAN line; the human-machine interaction module sends a four-wheel drive mode operation instruction signal IHU_bCluUseChoise selected by the driver to the four-wheel drive controller through the CAN line.

[0079] The application layer of the four-wheel drive controller receives the clutch self-learning request signal sent by the bottom layer, starts the clutch self-learning logic operation, receives the actual engine speed signal for logic operation. If Ems_nEngSpd≥300, it is determined that the clutch self-learning function is activated, and starts to execute a four-wheel drive clutch control method proposed in an embodiment of the present application to obtain the KP point position of the four-wheel drive clutch;

[0080] 1. Determine the wear state of the four-wheel drive clutch according to the four-wheel drive clutch KP point position signal SLM_dstKp. If SLM_dstKp < the second set position threshold 1.8, it indicates that the four-wheel drive clutch is not severely worn, and the four-wheel drive controller controls the clutch to remain engaged, and the vehicle maintains the four-wheel drive mode; if SLM_dstKp≥the first set position threshold 2.2, it indicates that the four-wheel drive clutch wear exceeds the limit, and the four-wheel drive controller controls the clutch to disengage, and the vehicle stops the four-wheel drive mode; if the first set position threshold 2.2 > SLM_dstKp≥the second set position threshold 1.8, the four-wheel drive controller sets AWD_bCluWearSer to 1, indicating that the four-wheel drive clutch is severely worn.

[0081] 2. The human-machine interaction module performs logical judgment: If AWD_bCluWearSer is 1, the human-machine interaction module pops up a reminder message "The four-wheel drive clutch is severely worn. Please go to the service station to confirm the status of the four-wheel drive clutch" and a reminder message "Please select whether to stop the four-wheel drive mode". When the driver selects "Yes", the signal IHU_bCluUseChoise is set to 1, the reminder message disappears, the clutch is controlled to disengage, and the vehicle stops the four-wheel drive mode; if the driver selects "No", the signal IHU_bCluUseChoise is set to 0, the reminder message disappears, the four-wheel drive clutch remains engaged, and the vehicle maintains the four-wheel drive mode until after the end of this drive, the information reminder display function of the human-machine interaction module is restored together with the vehicle's four-wheel drive mode.

[0082] 3. Human-machine interaction results:

[0083] When the driver selects "Yes", IHU_bRerAWDdisconnect is set to 1. After that, AWD_bClu_disconnect is set to 1, and the four-wheel drive controller controls the clutch to disengage, and the vehicle stops the four-wheel drive mode;

[0084] When the driver selects "No": IHU_bRerAWDdisconnect is set to 0, the vehicle's four-wheel drive mode is maintained, the output torque of the clutch is obtained, and the torque limit coefficient is determined by looking up the table according to the KP value; the obtained output torque of the clutch is multiplied by the torque limit coefficient to obtain the target value of the output torque of the four-wheel drive clutch; the output torque of the four-wheel drive clutch is reduced to the target value of the output torque of the four-wheel drive clutch, thereby reducing the wear of the four-wheel drive clutch, extending the duration of four-wheel drive, and improving the user's driving experience and driving safety.

[0085] Therefore, a four-wheel drive clutch control method provided by an embodiment of the present application can control the four-wheel drive mode of the vehicle according to the wear state of the clutch, thereby ensuring the driving safety of the vehicle to a certain extent.

[0086] An embodiment of the present application further provides a four-wheel drive clutch control system, including:

[0087] A KP point position acquisition unit for acquiring the KP point position of the four-wheel drive clutch;

[0088] A clutch wear state judgment unit for judging the wear state of the four-wheel drive clutch according to the KP point position of the four-wheel drive clutch;

[0089] A four-wheel drive mode operation instruction acquisition unit for acquiring a four-wheel drive mode operation instruction when the wear state of the four-wheel drive clutch is severely worn;

[0090] A four-wheel drive mode control unit is configured to control the vehicle to stop the four-wheel drive mode when the four-wheel drive mode operation instruction is to stop the four-wheel drive mode; and to control the vehicle to maintain the four-wheel drive mode and reduce the clutch output torque when the four-wheel drive mode operation instruction is to maintain the four-wheel drive mode.

[0091] An embodiment of the present application further provides a computer device, which includes:

[0092] A processor, adapted to execute a computer program;

[0093] A computer-readable storage medium, in which a computer program is stored, and when the computer program is executed by the processor, it implements a four-wheel drive clutch control method further provided by the embodiment of the present application.

[0094] An embodiment of the present application further provides a computer-readable storage medium, which stores a computer program, and the computer program is adapted to be loaded and executed by a processor to implement a four-wheel drive clutch control method further provided by the embodiment of the present application.

[0095] An embodiment of the present application further provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, it implements a four-wheel drive clutch control method further provided by the embodiment of the present application.

[0096] The method further provided by the embodiment of the present application can be directly embodied as being executed by a hardware processor, or by a combination of hardware and software modules in the processor. The software module can be located in a mature storage medium in the art such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, register, etc. This storage medium is located in the memory, and the processor reads the information in the memory and combines its hardware to complete the steps of the above method. To avoid repetition, it will not be described in detail here.

[0097] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with this embodiment can be implemented by electronic hardware or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present application.

[0098] Although the specific implementation manners of the present invention have been described above in conjunction with the accompanying drawings, it is not a limitation on the protection scope of the present invention. Those skilled in the art should understand that based on the technical solutions of the present invention, various modifications or deformations that can be made by those skilled in the art without creative efforts are still within the protection scope of the present invention.

Claims

1. A four-wheel drive clutch control method, characterized in that: include: Get the KP point position of the four-wheel drive clutch; Determine the wear status of the four-wheel drive clutch according to the four-wheel drive clutch KP point position; When the wear state of the four-wheel drive clutch is serious, a four-wheel drive mode control instruction is obtained; When the four-wheel drive mode operation instruction is to stop the four-wheel drive mode, the vehicle is controlled to stop the four-wheel drive mode; When the four-wheel drive mode operation instruction is to maintain the four-wheel drive mode, the vehicle is controlled to maintain the four-wheel drive mode and the clutch output torque is reduced.

2. A four-wheel drive clutch control method as claimed in claim 1, characterized in that: When the wear state of the four-wheel drive clutch is excessive wear, the vehicle is controlled to stop the four-wheel drive mode; When the wear state of the four-wheel drive clutch is not worn, the vehicle is controlled to maintain the four-wheel drive mode.

3. A four-wheel drive clutch control method as claimed in claim 2, characterized in that: When the KP point position is greater than or equal to the first set position threshold, it is determined that the wear state of the four-wheel drive clutch is excessive wear; When the KP point position is less than the first set position threshold and greater than or equal to the second set position threshold, it is determined that the wear state of the four-wheel drive clutch is severe wear; When the KP point position is less than the second set position threshold, it is determined that the wear state of the four-wheel drive clutch is not worn.

4. A four-wheel drive clutch control method as claimed in claim 1, characterized in that: When the wear state of the four-wheel drive clutch is serious, a reminder message is issued asking whether to stop the four-wheel drive mode.

5. A four-wheel drive clutch control method as claimed in claim 1, characterized in that: When the four-wheel drive mode control instruction is to maintain the four-wheel drive mode, the clutch output torque is obtained; Determine the torque limit coefficient according to the KP point position of the four-wheel drive clutch; The obtained clutch output torque is multiplied by the torque limit coefficient to obtain a target value of the four-wheel drive clutch output torque; The four-wheel drive clutch output torque is controlled to be reduced to the four-wheel drive clutch output torque target value.

6. A four-wheel drive clutch control method as claimed in claim 5, characterized in that: The KP point position is linearly negatively correlated with the torque limit coefficient.

7. A four-wheel drive clutch control system, characterized in that: include: A KP point position acquisition unit, used to acquire the KP point position of the four-wheel drive clutch; A clutch wear state judgment unit, used to judge the wear state of the four-wheel drive clutch according to the KP point position of the four-wheel drive clutch; A four-wheel drive mode control instruction acquisition unit, used for acquiring a four-wheel drive mode control instruction when the wear state of the four-wheel drive clutch is severe wear; The four-wheel drive mode control unit is used to control the vehicle to stop the four-wheel drive mode when the four-wheel drive mode operation instruction is to stop the four-wheel drive mode; when the four-wheel drive mode operation instruction is to maintain the four-wheel drive mode, control the vehicle to maintain the four-wheel drive mode and reduce the clutch output torque.

8. An electronic device, characterized in that: The device comprises: a processor adapted to execute a computer program; A computer-readable storage medium, wherein a computer program is stored in the computer-readable storage medium, and when the computer program is executed by the processor, a four-wheel drive clutch control method according to any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and the computer program is suitable for being loaded by a processor and executing a four-wheel drive clutch control method as described in any one of claims 1-6.

10. A computer program product, characterized in that The computer program product includes a computer program, and when the computer program is executed by a processor, a four-wheel drive clutch control method as described in any one of claims 1 to 6 is implemented.

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