Control method and equipment for HHC (hill start assist)

Abstract

The invention relates to a control method for an uphill start assist HHC. The method comprises the steps that it is determined that the uphill start assist HHC is activated; whether the gear is switched from the D / R gear to the P gear or not is judged; and when the gear is switched from the D / R gear to the P gear and parking braking is not applied, the uphill start assist HHC is kept in an activated state, and the pressure maintaining time of the uphill start assist HHC is prolonged. The application also relates to a control device of an uphill launch assist HHC, a computer program product and a braking system.

Description

Technical Field

[0001] The present application relates to the field of vehicle control, and more specifically, to a control method and device for a hill start assist (HHC), a computer program product, and a braking system. Background Art

[0002] For the existing Hill Start Assist (HHC) function, if the driver switches the gear from Drive (D) or Reverse (R) to Park (P) while it is active, the HHC function will be immediately deactivated. However, there is a possibility that the vehicle may roll backwards - for example, if the driver releases the brake pedal immediately after shifting the gear to Park, there is a certain time delay in applying the parking brake, so the vehicle may roll backwards on the slope. Summary of the Invention

[0003] According to one aspect of the present application, a control method for hill start assist HHC is provided, the method comprising: determining that the hill start assist HHC is activated; judging whether the gear is switched from D / R gear to P gear; and when the gear is switched from D / R gear to P gear and the parking brake is not applied, maintaining the hill start assist HHC in an activated state and extending the holding time of the hill start assist HHC.

[0004] As a supplement or alternative to the above solution, the method further includes: during the extended pressure holding time of the hill start assist HHC, when the gear is switched from P gear to D gear or R gear, exiting the extended pressure holding and switching back to normal pressure holding.

[0005] As a supplement or alternative to the above solution, the method further includes: during the extended dwell time of the hill start assist HHC, when the gear is switched from P gear to N gear or the parking brake is applied, exiting the hill start assist HHC.

[0006] During the extended holding time of the hill start assist HHC, when the gear is switched from the P gear to another gear or the parking brake is applied, the hill start assist HHC is exited.

[0007] As a supplement or alternative to the above solution, the method further includes: exiting the hill start assist HHC when a preset extended pressure holding time threshold of the hill start assist HHC is exceeded.

[0008] As a supplement or alternative to the above solution, in the above method, the hill start assist HHC is automatically activated when the vehicle is stationary and in an uphill driving condition, the brake pedal is released, the accelerator is not depressed, and the parking brake is not applied.

[0009] According to another aspect of the present application, there is provided a control device of a hill start assist HHC, the device comprising: determining means for determining that the hill start assist HHC has been activated; judging means for judging whether a gear is switched from D / R to P; and controlling means for keeping the hill start assist HHC in an activated state when the gear is switched from D / R to P and a parking brake is not applied, and extending a pressure maintaining time of the hill start assist HHC.

[0010] As a supplement or alternative to the above-mentioned solutions, in the above-mentioned device, the controlling means is further configured to: during the extended pressure maintaining time of the hill start assist HHC, when the gear is switched from P to D or R, exit the extended pressure maintaining and switch back to normal pressure maintaining.

[0011] As a supplement or alternative to the above-mentioned solutions, in the above-mentioned device, the controlling means is further configured to: during the extended pressure maintaining time of the hill start assist HHC, when the gear is switched from P to N or a parking brake is applied, exit the hill start assist HHC.

[0012] As a supplement or alternative to the above-mentioned solutions, in the above-mentioned device, the controlling means is further configured to: when a preset extended pressure maintaining time threshold of the hill start assist HHC is exceeded, exit the hill start assist HHC.

[0013] As a supplement or alternative to the above-mentioned solutions, in the above-mentioned device, the hill start assist HHC is automatically activated when the vehicle is at rest and in a hill working condition, a brake pedal is released, an accelerator is not depressed, and a parking brake is not working.

[0014] According to yet another aspect of the present application, there is provided a computer readable storage medium, the medium comprising instructions which, when executed, perform the method as described above.

[0015] According to yet another aspect of the present application, there is provided a computer program product comprising a computer program which, when executed by a processor, performs the method as described above.

[0016] According to yet another aspect of the present application, there is provided a brake system comprising the device as described above.

[0017] The control scheme of the hill start assist HHC of the embodiments of the present application determines whether the gear is switched from D / R range to P range after determining that the hill start assist HHC has been activated. And when the gear is switched from D / R range to P range and the parking brake is not applied, the hill start assist HHC is kept in the activated state, and the pressure maintaining time of the hill start assist HHC is prolonged. In this way, the hill start assist HHC function will remain activated before the parking brake works, prolonging the pressure maintaining time of the hill start assist HHC function, and ensuring that the vehicle is parked on the slope. BRIEF DESCRIPTION OF DRAWINGS

[0018] The above and other objects and advantages of the present application will become more apparent by describing in detail the following embodiments thereof in connection with the accompanying drawings, in which like reference numerals refer to like elements throughout the several views.

[0019] Figure 1 A flowchart of a control method of a hill start assist HHC according to an embodiment of the present application is shown;

[0020] Figure 2 A structural diagram of a control device of a hill start assist HHC according to an embodiment of the present application is shown;

[0021] Figure 3 A control flowchart of a hill start assist HHC prolonging pressure maintaining time according to an embodiment of the present application is shown; and

[0022] Figures 4 to 7 A schematic diagram of pressure output of a hill start assist HHC changing with time under different working conditions according to one or more embodiments of the present application is shown. DETAILED DESCRIPTION

[0023] In the following, the control scheme of a hill start assist HHC according to exemplary embodiments of the present application will be described in detail with reference to the accompanying drawings.

[0024] Figure 1 A flowchart of a control method 1000 of a hill start assist HHC according to an embodiment of the present application is shown. As shown in Figure 1 The control method 1000 of the hill start assist HHC includes the following steps:

[0025] In step S110, it is determined that the hill start assist HHC has been activated;

[0026] In step S120, it is determined whether the gear is switched from D / R range to P range; and

[0027] In step S130, when the gear is switched from D / R to P and the parking brake is not applied, the hill start assist HHC is kept activated and the pressure maintaining time of the hill start assist HHC is prolonged.

[0028] In the context of the present application, the hill start assist HHC function is also referred to as a hill holder function, which functions to temporarily maintain the braking state of the vehicle after the driver releases the brake pedal, allowing the driver time to transfer his foot from the brake pedal to the accelerator pedal, thereby preventing the vehicle from rolling down the hill. In one or more embodiments, the hill start assist HHC is automatically activated when the vehicle is stationary and in an uphill working condition, the brake pedal is released, the accelerator is not depressed, and the parking brake is not working. After the hill start assist HHC is activated (started), the system temporarily applies the brake to the wheels to maintain the stability of the vehicle on the hill. In general, the hill start assist HHC function is a very practical driving assistance function, especially in urban traffic congestion or environments with many hills, which can help the driver control the vehicle more easily and avoid accidents caused by rolling.

[0029] As described in the background, for the existing hill start assist HHC function, if the gear is switched from forward or reverse (D / R) to park (P) during the activation of the HHC function, the hill start assist HHC will immediately exit and release the pressure.

[0030] Unlike the existing hill start assist HHC function, in the control method 1000 of the hill start assist HHC of the above embodiments, referring to step S130, when the gear is switched from D / R to P and the parking brake is not applied, the hill start assist HHC is kept activated and the pressure maintaining time of the hill start assist HHC is prolonged.

[0031] Here, "the parking brake is not applied" means that the parking brake is not working or is not fully in the clamping state.

[0032] In general, the duration of the hill start assist HHC (i.e. the pressure maintaining time) is usually short, for example, about 1 second. The control method 1000 of the embodiments of the present application proposes to prolong the pressure maintaining time under certain conditions (i.e. when the gear is switched from D / R to P and the parking brake is not applied) to avoid the risk of the vehicle rolling backward due to the delay in the application of the parking brake.

[0033] Although Figure 1Not shown, in one embodiment, the control method 1000 further includes: during the extended hold time of the hill start assist HHC, when the gear is switched from P to D or R, exiting the extended hold and switching back to normal hold. In one embodiment, the control method 1000 further includes: during the extended hold time of the hill start assist HHC, when the gear is switched from P to N or the parking brake is applied, exiting the hill start assist HHC. In one embodiment, the control method 1000 further includes: when a preset extended hold time threshold (i.e., a maximum extended hold time) for the hill start assist HHC is exceeded, exiting the hill start assist HHC.

[0034] Figure 3 FIG. 1 shows a control flow diagram of extending the holding time of the hill start assist HHC according to an embodiment of the present application. Figure 3 As shown, the entire process begins in step S310. Next, in step S320, it is determined whether Hill Start Assist (HHC) is activated. If not, step S360 is executed to exit Hill Start Assist (HHC). If so, steps S325 and S330 are executed. In step S325, it is determined whether the current gear has been switched to P. If so, the process proceeds to step S340 to extend the hold time. In step S330, it is determined whether the current gear is in P (i.e., it has been previously switched to P and is still in P). If so, step S335 is executed; otherwise, the process proceeds to step S360 to exit Hill Start Assist (HHC). In step S335, it is further determined whether the vehicle is currently in the "extended hold time period" (i.e., it has not exceeded a preset hold time threshold). If so, step S340 is executed to extend the hold time; otherwise, the process proceeds to step S360 to exit Hill Start Assist (HHC). Furthermore, in step S350, it is determined whether the parking brake is applied. If not (ie, not applied yet), step S340 is executed to extend the pressure holding time, otherwise the process jumps to step S360 to exit the hill start assist HHC.

[0035] from Figure 3 As you can see, when the driver shifts from drive or reverse to park, HHC remains active and maintains pressure to hold the vehicle on the slope. Furthermore, if the extended hold time is detected and the current gear is P, the vehicle will maintain pressure. If the driver shifts gears or exceeds the maximum extended hold time, HHC will disengage. HHC will also disengage if the parking brake is detected to be applied during the extended hold period (i.e., the vehicle can now be parked on the slope).

[0036] Figures 4 to 7FIG2 shows a schematic diagram showing the change of the pressure output of the hill start assist HHC over time under different working conditions according to one or more embodiments of the present application. Figure 4 , which shows a first operating condition, namely, during the activation of the hill start assist HHC (i.e., during pressure output), the gear is switched to park at time 410. Unlike conventional hill start assist HHCs, the control scheme of the hill start assist HHC in this embodiment of the present application keeps the hill start assist HHC active and enters an extended pressure hold period (as shown at 430). The hill start assist HHC is not terminated until the maximum extended pressure hold time (as shown at 420) is exceeded.

[0037] Figure 5 The second operating condition is shown, in which the gear is switched to park at time 510 while the hill start assist HHC is active (i.e., during pressure output). Unlike conventional hill start assist HHCs, the control scheme of the hill start assist HHC in this embodiment of the present application maintains the hill start assist HHC in an active state and enters an extended pressure hold period (as shown at 530). During this extended pressure hold period 530, if the parking brake is detected to be applied (as shown at 520), the hill start assist HHC is immediately disengaged (even if the maximum extended pressure hold time has not yet been reached).

[0038] Figure 6 The third operating condition is shown, in which the gear is switched to Park at time 610 while the Hill Start Assist (HHC) is active (i.e., during pressure output). Unlike conventional Hill Start Assist (HHC), the Hill Start Assist (HHC) control scheme in this embodiment of the present application maintains the Hill Start Assist (HHC) in an extended pressure hold period (as shown at 640). During this extended pressure hold period 640, the driver shifts the gear from P to D / R (as shown at 620), indicating a driver's intention to start the vehicle, thereby exiting the delayed pressure hold logic. Subsequently, when the driver releases the brake pedal, the Hill Start Assist (HHC) is activated, maintaining pressure for, for example, 1 second (as shown at 650). Furthermore, after the Hill Start Assist (HHC) pressure hold period (e.g., 1 second) has expired (as shown at 630), the Hill Start Assist (HHC) is immediately exited.

[0039] Figure 7A fourth working condition is shown, in which during the hill start assist HHC activation (i.e. during the pressure output), at the time point shown in 710, the gear is switched to the parking gear. Unlike the existing hill start assist HHC, the control scheme of the hill start assist HHC of the embodiments of the present application keeps the hill start assist HHC in the activated state and enters an extended pressure maintaining period (as shown in 730). During the extended pressure maintaining period 730, if it is detected that the gear is switched to the neutral gear (as shown in 720), the hill start assist HHC is exited immediately (regardless of whether the driver releases the brake pedal).

[0040] In addition, it is easy for those skilled in the art to understand that the control method of the hill start assist HHC provided by one or more embodiments of the present application can be implemented by a computer program. For example, the computer program is contained in a computer program product, and when the computer program is executed by a processor, the control method of the hill start assist HHC of one or more embodiments of the present application is implemented. For another example, when a computer readable storage medium (such as a U disk) in which the computer program is stored is connected to a computer, the control method of the hill start assist HHC of one or more embodiments of the present application can be executed by running the computer program.

[0041] Reference Figure 2 , Figure 2 A structural schematic diagram of a control device 2000 of the hill start assist HHC according to an embodiment of the present application is shown. As shown in Figure 2 The control device 2000 of the hill start assist HHC includes a determination apparatus 210, a judgment apparatus 220 and a control apparatus 230. The determination apparatus 210 is configured to determine that the hill start assist HHC has been activated; the judgment apparatus 220 is configured to judge whether the gear is switched from the D / R gear to the P gear; and the control apparatus 230 is configured to keep the hill start assist HHC in the activated state when the gear is switched from the D / R gear to the P gear and the parking brake is not applied, and to extend the pressure maintaining time of the hill start assist HHC.

[0042] In the context of the present application, the hill start assist HHC function is also referred to as a hill holder function, which functions to temporarily maintain the braking state of the vehicle after the driver releases the brake pedal, allowing the driver to have time to transfer his foot from the brake pedal to the accelerator pedal, thereby preventing the vehicle from rolling down the hill. In one or more embodiments, the hill start assist HHC is automatically activated when the vehicle is at rest and in an uphill working condition, the brake pedal is released, the accelerator is not depressed, and the parking brake is not working. After the hill start assist HHC is activated (started), the system temporarily applies the brake to the wheels to maintain the stability of the vehicle on the hill. In general, the hill start assist HHC function is a very practical driving assistance function, especially in urban traffic congestion or environments with many hills, which can help the driver control the vehicle more easily and avoid accidents caused by rolling.

[0043] As described in the background section, for the existing hill start assist HHC function, if the gear is switched from forward or reverse (D / R) to park (P) during the activation of the HHC function, the hill start assist HHC will immediately exit and release the pressure.

[0044] Unlike the existing hill start assist HHC function, in the control device 2000 of the hill start assist HHC of the above embodiments, the control means 230 is configured to maintain the hill start assist HHC in an activated state when the gear is switched from D / R to P and the parking brake is not applied, and to extend the pressure maintaining time of the hill start assist HHC.

[0045] Here, "the parking brake is not applied" means that the parking brake is not working or is not fully in the clamped state.

[0046] In general, the duration of the hill start assist HHC (i.e. the pressure maintaining time) is usually short, for example, about 1 second. The control device 2000 of the embodiments of the present application can extend this pressure maintaining time under certain conditions (i.e. when the gear is switched from D / R to P and the parking brake is not applied) to avoid the risk of the vehicle rolling backward due to the delay in the application of the parking brake.

[0047] In one embodiment, the control means 230 is further configured to, during the extended pressure maintaining time of the hill start assist HHC, exit the extended pressure maintaining and switch back to normal pressure maintaining when the gear is switched from P to D or R. In one embodiment, the control means 230 is further configured to, during the extended pressure maintaining time of the hill start assist HHC, exit the hill start assist HHC when the gear is switched from P to N or the parking brake is applied.

[0048] In one embodiment, the control device 230 is further configured to: when a preset prolong pressure maintaining time threshold of the uphill start assist HHC is exceeded, the uphill start assist HHC is exited.

[0049] In one or more embodiments, the control device 2000 of the uphill start assist HHC of the above embodiments can be integrated in various types of brake systems, such as the vehicle body stability system ESP or the intelligent integrated brake system IPB.

[0050] In summary, the control scheme of the uphill start assist HHC of the embodiments of the present application determines whether the gear is switched from D / R to P after the uphill start assist HHC is activated. When the gear is switched from D / R to P and the parking brake is not applied, the uphill start assist HHC remains activated and the pressure maintaining time of the uphill start assist HHC is prolonged. In this way, the uphill start assist HHC function will remain activated before the parking brake works, the pressure maintaining time of the uphill start assist HHC function is prolonged, and the vehicle is ensured to be parked on the slope.

[0051] The above examples mainly illustrate the control scheme of the uphill start assist HHC of the embodiments of the present application. Although only some of the embodiments of the present application are described, it should be understood by those skilled in the art that the present application can be implemented in many other forms without departing from the spirit and scope of the present application. Therefore, the examples and embodiments shown are considered illustrative rather than limiting, and the present application can encompass various modifications and alternatives without departing from the spirit and scope of the present application as defined in the claims.

Claims

1. A control method for hill start assist HHC, characterized in that: The method comprises: Determining that the hill start assist HHC is activated; Determine whether the gear is switched from D / R to P; and When the gear is switched from the D / R gear to the P gear and the parking brake is not applied, the hill start assist HHC is kept in an activated state, and the pressure holding time of the hill start assist HHC is extended.

2. The method according to claim 1, wherein The method further comprises: During the extended dwell time of the hill start assist HHC, when the gear is switched from the P gear to the N gear or the parking brake is applied, the hill start assist HHC is exited.

3. The method according to claim 1, wherein The method further comprises: When a preset extended pressure holding time threshold of the hill start assist HHC is exceeded, the hill start assist HHC is exited.

4. The method according to claim 1, wherein The hill start assist HHC is automatically activated when the vehicle is stationary and driving uphill, the brake pedal is released, the accelerator is not depressed, and the parking brake is not applied.

5. A control device for a hill start assist HHC, characterized in that: The device comprises: a determining device for determining that the hill start assist HHC is activated; A judging device, used to judge whether the gear position is switched from D / R gear to P gear; and The control device is used to keep the hill start assist HHC in an activated state and extend the holding time of the hill start assist HHC when the gear is switched from the D / R gear to the P gear and the parking brake is not applied.

6. The apparatus of claim 5, wherein: The control device is further configured to: During the extended dwell time of the hill start assist HHC, when the gear is switched from the P gear to the N gear or the parking brake is applied, the hill start assist HHC is exited.

7. The apparatus of claim 5, wherein: The control device is further configured to: When a preset extended pressure holding time threshold of the hill start assist HHC is exceeded, the hill start assist HHC is exited.

8. The apparatus of claim 5, wherein: The hill start assist HHC is automatically activated when the vehicle is stationary and driving uphill, the brake pedal is released, the accelerator is not depressed, and the parking brake is not applied.

9. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 4 is implemented.

10. A braking system, characterized in that: The system comprises the apparatus according to any one of claims 5 to 8.

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