A shift control method for improving the stability of a vehicle on a curve

Abstract

The present application belongs to the field of automobile technology, and particularly relates to a shift control method for improving the stability of a vehicle in a curved road working condition. The method comprises the following steps: step one, judging whether the activation condition of the over-curve upshift prohibition function is met, and if yes, going to step two; step two, judging whether the engine speed is over-speed, and if yes, upshifting by one gear and keeping the gear position after upshifting, and if no, going to step three; step three, prohibiting upshifting; step four, judging whether the exit condition of the over-curve upshift prohibition function is met, and if yes, upshifting according to the shift map every certain time to exit the function, and if no, keeping the gear position. The present application can judge the over-curve condition of the vehicle based on the vehicle speed and the wheel speed difference, execute upshift prohibition, handle the situation of estimated over-speed, increase the interval time of out-curve upshifting, and include the use of a spare tire into the activation judgment condition, so as to ensure the upshifting quality, vehicle stability and safety in the over-curve condition, and improve the driving experience.

Description

Technical Field

[0001] This invention belongs to the field of automotive technology, specifically a shift control method to improve the stability of a vehicle under cornering conditions. Background Technology

[0002] Stability is a crucial function for ensuring vehicle safety and has significant implications for driving safety. When cornering, we typically release the accelerator and lightly apply the brakes to reduce speed for safe cornering. However, releasing the accelerator during this process triggers an upshift according to the shift chart, resulting in insufficient power during cornering. Conversely, when exiting a corner, we press the accelerator again, causing a downshift. On winding roads, frequent upshifting and downshifting can cause the clutch to overheat, affecting shift quality, safety, and the driving experience. Summary of the Invention

[0003] This invention provides a shift control method to improve vehicle stability in cornering conditions. It can determine the vehicle's cornering status based on vehicle speed and wheel speed difference, enforce upshift prohibition, handle the situation of estimated overspeed, increase the interval time for upshifting when exiting the corner, and include spare tire use in the function activation judgment condition to ensure shift quality, vehicle stability, and safety when cornering, thereby improving the driving experience. It solves the problem that frequent upshifting and downshifting operations can cause the clutch to overheat when driving on roads with many curves, affecting shift quality, safety, and driving experience.

[0004] The technical solution of this invention is described below in conjunction with the accompanying drawings:

[0005] A shift control method for improving vehicle stability under cornering conditions includes the following steps:

[0006] Step 1: Determine if the activation conditions for the cornering upshift prohibition function are met. If they are met, proceed to Step 2.

[0007] Step 2: Determine if the engine speed is too high. If so, shift to 1st gear and maintain the position after shifting. If not, proceed to Step 3.

[0008] Step 3: Do not upshift;

[0009] Step 4: Determine if the exit conditions for the cornering upshift prohibition function are met. If yes, gradually upshift according to the shift diagram at regular intervals to exit this function; otherwise, maintain the gear.

[0010] Furthermore, the activation conditions for the cornering upshift prohibition function in step one are as follows:

[0011] Condition 11) Current driving mode: Non-manual mode;

[0012] Condition 12) Gear shift lever position: D gear;

[0013] Condition 13) Vehicle speed ≥ cornering function activation speed threshold V Corner_start ;

[0014] Condition 14) Fault mode: No fault;

[0015] Condition 15) Difference in rotational speed between the left and right non-drive wheels: When the difference in rotational speed between the left and right non-drive wheels is greater than or equal to the cornering function activation threshold LRDiff start Beyond a certain time T LRDiff_start ;

[0016] Condition 16) Spare tire status: Not in use;

[0017] Condition 17) Cornering control: Not activated.

[0018] The activation condition for the cornering upshift prohibition function is met when all of the following conditions are met: Condition 11), Condition 12), Condition 13), Condition 14), Condition 15), Condition 16), and Condition 17).

[0019] Furthermore, the exit conditions for the cornering upshift prohibition function in step four are as follows:

[0020] Condition 21) Current driving mode: Manual transmission mode;

[0021] Condition 22) Gear shift lever position: P, R, N;

[0022] Condition 23) Vehicle speed < cornering function deactivation speed threshold V Corner_end ;

[0023] Condition 24) Fault mode: A fault was detected;

[0024] Condition 25) Speed ​​difference between the left and right non-drive wheels: When the speed difference between the left and right non-drive wheels is less than the cornering function exit threshold LRDiff end Beyond a certain time T LRDiff_end ;

[0025] Condition 26) Spare tire status: A spare tire has been detected;

[0026] When conditions 21), 22), 23), 24), 25), and 26) are met, the exit condition for the function of temporarily prohibiting upshifting during cornering is satisfied.

[0027] Furthermore, the method for detecting the status of the spare tire is as follows:

[0028] Condition 31) The difference between the speed difference between the left and right front wheels and the speed difference between the left and right rear wheels is greater than or equal to the Inhibit limit. Map And last for a certain period of time T FR_LR_diff ;

[0029] Condition 32) The speed difference between the left and right rear wheels is greater than or equal to the speed difference between the left and right non-drive wheels of the activated function, LRDiffstart_ Map And lasting for a certain period of time T LRdiff ;

[0030] When either condition 31) or condition 32) is met, it is determined that the spare tire is being used, and the cornering function is prohibited.

[0031] The beneficial effects of this invention are as follows:

[0032] This invention can quickly determine the vehicle's cornering status based on vehicle speed, wheel speed difference, etc., and enforce upshift prohibition. It also handles the situation of estimated overspeed, increases the interval time for upshifting when exiting a corner, and incorporates spare tire use into the function activation judgment condition to ensure the quality of gear shifting, vehicle stability, and safety when cornering, thereby improving the driving experience. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 Logic diagram for the function to prevent upshifting while cornering;

[0035] Figure 2 This is a diagram illustrating the function that prevents upshifting when cornering. Detailed Implementation

[0036] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0037] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0038] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0039] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0040] A shift control method for improving vehicle stability under cornering conditions includes the following steps:

[0041] See Figure 1 Step 1: Determine if the activation conditions for the cornering upshift prohibition function are met. If they are met, proceed to Step 2.

[0042] The activation conditions for the cornering upshift prohibition function are as follows:

[0043] Condition 11) Current driving mode: Non-manual mode;

[0044] Condition 12) Gear shift lever position: D gear;

[0045] Condition 13) Vehicle speed ≥ cornering function activation speed threshold V Corner_start ;

[0046] The cornering function activates the vehicle speed threshold V. Corner_start Confirmed through actual vehicle calibration, for example, but not limited to, 30km / h;

[0047] Condition 14) Fault mode: No fault;

[0048] Condition 15) Difference in rotational speed between the left and right non-drive wheels: When the difference in rotational speed between the left and right non-drive wheels is greater than or equal to the cornering function activation threshold LRDiff start Beyond a certain time T LRDiff_start ;

[0049] The T LRDiff_start The threshold is confirmed through actual vehicle calibration, for example, but not limited to 900 msec;

[0050] Condition 16) Spare tire status: Not in use;

[0051] Condition 17) Cornering control: Not activated.

[0052] The activation condition for the cornering upshift prohibition function is met when all of the following conditions are met: Condition 11), Condition 12), Condition 13), Condition 14), Condition 15), Condition 16), and Condition 17).

[0053] Step 2: Determine if the engine speed is too high. If so, shift to 1st gear and maintain the position after shifting. If not, proceed to Step 3.

[0054] This invention takes into account overspeed conditions. When overspeed is anticipated, the gear is shifted up one gear first and then upshifting is prohibited to prevent overspeed.

[0055] Step 3: Do not upshift;

[0056] See Figure 2 Step 4: Determine if the exit conditions for the cornering upshift prohibition function are met. If so, at regular intervals T... upshiftdelay Shift up gradually according to the shift diagram to exit this function; otherwise, maintain the gear.

[0057] The T upshiftdelay The threshold is confirmed through actual vehicle calibration, for example, but not limited to 1000 msec; the deactivation conditions for the cornering upshift prohibition function are as follows:

[0058] Condition 21) Current driving mode: Manual transmission mode;

[0059] Condition 22) Gear shift lever position: P, R, N;

[0060] Condition 23) Vehicle speed < cornering function deactivation speed threshold V Corner_end ;

[0061] The cornering function activates the vehicle speed threshold V. Corner_end Confirmed through actual vehicle calibration, for example, but not limited to, 15km / h;

[0062] Condition 24) Fault mode: A fault was detected;

[0063] Condition 25) Speed ​​difference between the left and right non-drive wheels: When the speed difference between the left and right non-drive wheels is less than the cornering function exit threshold LRDiff end Beyond a certain time T LRDiff_end ;

[0064] The T LRDiff_end The threshold is confirmed through actual vehicle calibration, for example, but not limited to 1600 msec;

[0065] Condition 26) Spare tire status: A spare tire has been detected;

[0066] When conditions 21), 22), 23), 24), 25), and 26) are met, the exit condition for the function of temporarily prohibiting upshifting during cornering is satisfied.

[0067] When the exit conditions are met, the interval between upshifts is increased to ensure the quality of gear shifts and vehicle stability when upshifting out of a curve.

[0068] The method for detecting the status of the spare tire is as follows:

[0069] Condition 31) The difference between the speed difference between the left and right front wheels and the speed difference between the left and right rear wheels, i.e., LRDiff_front - LRDiff_rear, is greater than or equal to the function prohibition limit Inhibit_. Map And last for a certain period of time T FR_LR_diff ;

[0070] The T FR_LR_diff The threshold is confirmed through actual vehicle calibration, for example, but not limited to 10,000 msec;

[0071] Condition 32) The speed difference between the left and right rear wheels, i.e., LRDiff_rear, is greater than or equal to the speed difference between the left and right non-drive wheels of the activated function, LRDiffstart_. Map And lasting for a certain period of time T LRdiff ;

[0072] The T LRdiff The threshold is confirmed through actual vehicle calibration, for example, but not limited to 10,000 msec;

[0073] When either condition 31) or condition 32) is met, it is determined that the spare tire is being used, and the cornering function is prohibited.

[0074] This invention takes into account the safety of using a spare tire and includes the use of a spare tire as a judgment condition.

[0075] In summary, this invention can quickly determine the vehicle's cornering status based on vehicle speed, wheel speed difference, etc., and enforce upshift prohibition. It also addresses the situation of estimated overspeed and increases the interval time for upshifting when exiting a corner. Furthermore, it incorporates spare tire usage into the function activation judgment condition to ensure the quality of gear shifting, vehicle stability, and safety when cornering, thereby improving the driving experience.

[0076] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A shift control method for improving vehicle stability under cornering conditions, characterized in that, Includes the following steps: Step 1: Determine if the activation conditions for the cornering upshift prohibition function are met. If they are met, proceed to Step 2. Step 2: Determine if the engine speed is too high. If so, shift to 1st gear and maintain the position after shifting. If not, proceed to Step 3. Step 3: Do not upshift; Step 4: Determine if the exit conditions for the cornering upshift prohibition function are met. If yes, gradually upshift according to the shift diagram at regular intervals to exit this function; otherwise, maintain the gear. The activation conditions for the cornering upshift prohibition function in step one are as follows: Condition 11) Current driving mode: Non-manual mode; Condition 12) Gear shift lever position: D gear; Condition 13) Vehicle speed ≥ cornering function activation speed threshold V Corner_start ; Condition 14) Fault mode: No fault; Condition 15) Difference in rotational speed between the left and right non-drive wheels: When the difference in rotational speed between the left and right non-drive wheels is greater than or equal to the cornering function activation threshold LRDiff start Beyond a certain time T LRDiff_start ; Condition 16) Spare tire status: Not in use; Condition 17) Cornering control: Not activated; The activation condition for the cornering upshift prohibition function is met when all of the following conditions are met: The conditions for disabling the cornering upshift prohibition function in step four are as follows: Condition 21) Current driving mode: Manual transmission mode; Condition 22) Gear shift lever position: P, R, N; Condition 23) Vehicle speed < cornering function deactivation speed threshold V Corner_end ; Condition 24) Fault mode: A fault was detected; Condition 25) Speed ​​difference between the left and right non-drive wheels: When the speed difference between the left and right non-drive wheels is less than the cornering function exit threshold LRDiff end Beyond a certain time T LRDiff_end ; Condition 26) Spare tire status: A spare tire has been detected; When conditions 21), 22), 23), 24), 25), and 26) are met, the exit condition for the temporary cornering upshift prohibition function is satisfied; The method for detecting the status of the spare tire is as follows: Condition 31) The difference between the speed difference between the left and right front wheels and the speed difference between the left and right rear wheels is greater than or equal to the Inhibit limit. Map And last for a certain period of time T FR_LR_diff ; Condition 32) The speed difference between the left and right rear wheels is greater than or equal to the speed difference between the left and right non-drive wheels of the activated function, LRDiffstart_ Map And lasting for a certain period of time T LRdiff ; When either condition 31) or condition 32) is met, it is determined that the spare tire is being used, and the cornering function is prohibited.

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