Vehicle and automatic transmission shift control method, device and storage medium thereof

Abstract

The present invention discloses a vehicle and its automatic transmission shift control method, device, and storage medium. The automatic transmission shift control method includes: obtaining the vehicle's theoretical speed and an anti-lock braking signal from the vehicle's anti-lock braking system in real time; the anti-lock braking signal includes at least the front axle speed of the anti-lock braking system; when the anti-lock braking system is determined to be in a normal state based on the anti-lock braking signal, determining the vehicle's current driving condition based on the vehicle's theoretical speed and the front axle speed of the anti-lock braking system; the vehicle's driving condition includes at least a low-adhesion road condition; and when the vehicle's current driving condition is a low-adhesion road condition, controlling the current gear position of the automatic transmission to remain unchanged. The above technical solution can prevent the vehicle from stalling due to a momentary loss of vehicle power caused by automatic transmission shifting when the vehicle is traveling on a low-adhesion road surface.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control technology, and in particular to a vehicle and an automatic transmission shift control method, device and storage medium thereof. Background Art

[0002] The automatic transmission can control the separation and engagement of the clutch in the transmission gear structure, as well as the braking and release of the brake according to the vehicle speed and engine speed, so as to change the power transmission route of the transmission gear mechanism and realize the change of transmission gear. This can reduce the driver's labor intensity and has the advantages of simple structure, simple control and low cost.

[0003] However, since automatic transmissions require the clutch to be disengaged during gear shifts, decoupling the engine from the automatic transmission, this loss of power can cause the engine speed to drop to a certain extent. This is particularly true when driving on low-adhesion surfaces, such as icy, snowy, or muddy roads, where the drive wheels are prone to slipping. This can cause the drive wheels to accelerate rapidly, leading to a sharp increase in engine speed. However, the actual vehicle speed is relatively low. If automatic transmission shifts (e.g., upshifts) based on these engine speeds and vehicle speed are used, the vehicle will experience a momentary loss of power, resulting in a stall and an inability to navigate low-adhesion surfaces, compromising safety and stability. Summary of the Invention

[0004] The present invention provides a vehicle and an automatic transmission shift control method, device and storage medium thereof, so as to solve the technical problem in the prior art that a vehicle cannot smoothly pass through a low-adhesion road surface.

[0005] According to one aspect of the present invention, there is provided an automatic transmission shift control method, which is applied to a vehicle and includes:

[0006] Acquiring in real time the theoretical speed of the vehicle and an anti-lock braking signal of an anti-lock braking system in the vehicle; the anti-lock braking signal at least includes the front axle speed of the anti-lock braking system;

[0007] When it is determined according to the anti-lock braking signal that the anti-lock braking system is in a normal state, determining a current driving condition of the vehicle according to a theoretical vehicle speed and a front axle speed of the anti-lock braking system; the driving condition of the vehicle at least includes a low-adhesion road condition;

[0008] When the current driving condition of the vehicle is the low-adhesion road condition, the current gear position of the automatic transmission is controlled to remain unchanged.

[0009] Optionally, the vehicle's driving condition further includes a normal road condition; and the automatic transmission shift control method further includes:

[0010] When the current driving condition of the vehicle is the normal road condition, obtaining the rotation speed of the engine in the vehicle in real time;

[0011] determining a target gear position of the automatic transmission according to a rotational speed of the engine;

[0012] The current gear position of the automatic transmission is controlled to be the target gear position.

[0013] Optionally, determining the current driving condition of the vehicle according to the theoretical vehicle speed and the front axle speed of the anti-lock braking system includes:

[0014] determining a current vehicle speed difference based on the front axle speed of the anti-lock braking system and the theoretical vehicle speed at the current moment;

[0015] determining a current vehicle speed change rate based on a front axle speed of the anti-lock braking system at a current moment and a front axle speed of the anti-lock braking system at a previous moment;

[0016] The current driving condition of the vehicle is determined according to the current vehicle speed difference and the current vehicle speed change rate.

[0017] Optionally, determining the current driving condition of the vehicle according to the current vehicle speed difference and the current vehicle speed change rate includes:

[0018] Determining whether the current vehicle speed difference and the current vehicle speed change rate meet a first preset condition; the first preset condition being that the current vehicle speed difference is greater than a first preset difference and the current vehicle speed change rate is greater than a first preset change rate;

[0019] If so, it is determined that the current driving condition of the vehicle is the low-adhesion road condition.

[0020] Optionally, before determining that the current driving condition of the vehicle is the low-adhesion road condition, the method further includes:

[0021] Obtaining a first duration in which the current vehicle speed difference and the current vehicle speed change rate meet a first preset condition;

[0022] When the first duration is greater than a first preset time, it is determined that the current driving condition of the vehicle is a low-adhesion road condition.

[0023] Optionally, the vehicle's driving condition also includes a normal road condition;

[0024] Determining the current driving condition of the vehicle according to the current vehicle speed difference and the current vehicle speed change rate further includes:

[0025] determining whether the current vehicle speed difference and the current vehicle speed change rate satisfy a second preset condition; the second preset condition being that the current vehicle speed difference is less than the second preset difference and the current vehicle speed change rate is less than the second preset change rate; the second preset difference is less than or equal to the first preset difference and the second preset change rate is less than or equal to the first preset change rate;

[0026] If so, it is determined that the current driving condition of the vehicle is a normal adhesion road condition.

[0027] Optionally, before determining that the current driving condition of the vehicle is a normal adhesion road condition, the method further includes:

[0028] Obtaining a second duration during which the current vehicle speed difference and the current vehicle speed change rate meet a second preset condition;

[0029] When the second duration is greater than a second preset time, it is determined that the current driving condition of the vehicle is a normal adhesion road condition.

[0030] Optionally, determining the current driving condition of the vehicle according to the current vehicle speed difference and the current vehicle speed change rate further includes:

[0031] If the current vehicle speed difference and the current vehicle speed change rate do not satisfy the first preset condition, and the current vehicle speed difference and the current vehicle speed change rate do not satisfy the second preset condition, obtaining the driving condition of the vehicle at the previous moment;

[0032] The current driving condition of the vehicle is determined as the driving condition of the vehicle at the previous moment.

[0033] Optionally, obtaining the theoretical speed of the vehicle includes:

[0034] acquiring the output shaft speed of the automatic transmission in real time;

[0035] The theoretical vehicle speed is determined according to the output shaft speed of the automatic transmission.

[0036] Optionally, determining the theoretical speed of the vehicle according to the output shaft speed of the automatic transmission includes:

[0037] The theoretical speed of the vehicle is calculated according to the output shaft speed of the automatic transmission based on a first calculation formula; the first calculation formula is:

[0038]

[0039] Among them, V l is the theoretical speed of the vehicle, N is the output shaft speed of the automatic transmission, i gis the final reduction ratio of the automatic transmission, r is the tire radius of the vehicle, and k is the vehicle speed calculation coefficient.

[0040] Optionally, the automatic transmission shift control method further includes:

[0041] When it is determined according to the anti-lock braking signal that the anti-lock braking system is in an abnormal state, obtaining the speed of the engine in the vehicle in real time;

[0042] determining a target gear position of the automatic transmission according to a rotational speed of the engine;

[0043] The current gear of the automatic transmission is controlled to be the target gear.

[0044] Optionally, the automatic transmission shift control method further includes:

[0045] When the loss of the anti-lock braking signal is obtained, obtaining the loss time of the anti-lock braking signal;

[0046] Determining whether the loss time reaches a third preset time;

[0047] If so, it is determined that the anti-lock braking system is in an abnormal state.

[0048] Optionally, the automatic transmission shift control method further includes:

[0049] acquiring the rotation speed of the engine in real time;

[0050] determining whether the current speed of the engine is within a preset speed range;

[0051] If not, the current gear of the automatic transmission is adjusted by a preset gear change amount.

[0052] Optionally, adjusting the current gear of the automatic transmission by a preset gear change amount includes:

[0053] When the current speed of the engine is greater than an upper limit of the preset speed range, increasing the current gear of the automatic transmission by a preset gear increment;

[0054] When the current speed of the engine is less than a lower limit of the preset speed range, the current gear of the automatic transmission is reduced by a preset gear reduction amount.

[0055] According to another aspect of the present invention, there is provided an automatic transmission shift control device for use in a vehicle, comprising:

[0056] a signal acquisition module, configured to acquire in real time the theoretical speed of the vehicle and an anti-lock braking signal of an anti-lock braking system in the vehicle; the anti-lock braking signal at least including the front axle speed of the anti-lock braking system;

[0057] a working condition determination module, configured to determine a current driving condition of the vehicle based on a theoretical vehicle speed and a front axle speed of the anti-lock braking system when the anti-lock braking system is determined to be in a normal state according to the anti-lock braking signal; the driving condition of the vehicle at least includes a low-adhesion road condition;

[0058] The gear control module is used to control the current gear of the automatic transmission to remain unchanged when the current driving condition of the vehicle is the low-adhesion road condition.

[0059] According to another aspect of the present invention, there is provided a vehicle comprising: an engine, an engine controller, an automatic transmission, and an anti-lock braking system;

[0060] The engine controller is used to control the operating state of the engine;

[0061] The automatic transmission comprises a transmission controller and a transmission body; the transmission body is mechanically connected to the engine;

[0062] The transmission controller is connected to the engine controller and the anti-lock braking system respectively, and is used to execute the above-mentioned automatic transmission shift control method to control the operating state of the transmission body.

[0063] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the above-mentioned automatic transmission shift control method when executed.

[0064] The technical solution of the present invention obtains the vehicle's theoretical speed and the anti-lock braking signal of the anti-lock braking system in the vehicle in real time, and when it is determined that the anti-lock braking system is in a normal state based on the anti-lock braking signal, determines the vehicle's current driving condition based on the vehicle's theoretical speed and the front axle speed of the anti-lock braking system, so that when the vehicle's current driving condition is a low-adhesion road condition, the current gear of the automatic transmission is controlled to remain unchanged, preventing the vehicle from being stopped due to the instantaneous loss of power of the vehicle due to the gear change of the automatic transmission, thereby improving the safety and stability of the vehicle operation, and further helping to improve the driving experience.

[0065] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0067] Figure 1 This is a flow chart of an automatic transmission shift control method provided by the first embodiment of the present invention;

[0068] Figure 2 This is a flow chart of an automatic transmission shift control method provided by the second embodiment of the present invention;

[0069] Figure 3 This is a flow chart of an automatic transmission shift control method provided by the third embodiment of the present invention;

[0070] Figure 4 This is a flow chart of an automatic transmission shift control method provided by a fourth embodiment of the present invention;

[0071] Figure 5 This is a flow chart of an automatic transmission shift control method provided by a fifth embodiment of the present invention;

[0072] Figure 6 This is a structural block diagram of an automatic transmission shift control device provided in Example 6 of the present invention. DETAILED DESCRIPTION

[0073] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0074] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0075] Example 1

[0076] Figure 1 This is a flow chart of an automatic transmission shift control method provided by the first embodiment of the present invention. This embodiment is applicable to the case where a vehicle is traveling on a low-adhesion road surface. The method can be executed by an automatic transmission shift control device. The automatic transmission shift control device can be implemented in the form of hardware and / or software. The automatic transmission shift control device can be configured in a transmission controller. Figure 1 As shown, the method includes:

[0077] S110 : Acquire the theoretical vehicle speed and the anti-lock braking signal of the anti-lock braking system in the vehicle in real time.

[0078] The anti-lock braking signal at least includes the front axle speed of the anti-lock braking system. In addition, the anti-lock braking signal may also include a signal for controlling the vehicle to brake.

[0079] It is understood that the front axle speed of the anti-lock braking system can represent the actual operating speed of the vehicle. The theoretical speed of the vehicle is the speed determined by theoretical calculation based on signals from sensors at various positions in the vehicle.

[0080] S120: When it is determined according to the anti-lock braking signal that the anti-lock braking system is in a normal state, determine the current driving condition of the vehicle according to the theoretical vehicle speed and the front axle speed of the anti-lock braking system.

[0081] The vehicle's driving conditions include at least low-adhesion road conditions, which can be understood as conditions when the vehicle is traveling on a road surface with low friction, such as icy, snowy, or muddy roads. Due to the low friction on low-adhesion roads, when a vehicle is traveling on such roads, its drive wheels may slip, causing a sharp increase in the vehicle's drive wheel speed and engine speed. In this case, the vehicle speed determined based on the drive wheel speed and engine speed is high and inconsistent with the vehicle's actual driving speed. Conversely, when the vehicle is traveling on a normal road surface, the road surface has a certain amount of friction, making it less likely for the drive wheels to slip, allowing the drive wheels to rotate normally and the engine to operate at an appropriate speed. In this case, the vehicle speed determined based on the drive wheel speed and engine speed may be consistent with the vehicle's actual driving speed. In this way, when the theoretical speed of the vehicle is significantly different from the front axle speed of the anti-lock braking system that can represent the actual speed of the vehicle, it can be considered that the current driving condition of the vehicle is a low-adhesion road condition, and when the difference between the theoretical speed of the vehicle and the front axle speed of the anti-lock braking system that can represent the actual speed of the vehicle is within an acceptable error range, it can be considered that the current driving condition of the vehicle is a normal road condition.

[0082] Furthermore, since the vehicle's current driving condition is determined by both the vehicle's theoretical speed and the front axle speed of the vehicle's anti-lock braking system, the anti-lock braking signal of the anti-lock braking system must be reliable to ensure the accuracy of the determined current driving condition of the vehicle. Prior to determining the vehicle's current driving condition, whether the anti-lock braking system is in a normal state can be determined based on the anti-lock braking signal. If the anti-lock braking system is in a normal state, the obtained anti-lock braking signal is reliable, and the vehicle's current driving condition can be accurately determined based on the front axle speed in the anti-lock braking signal. Conversely, if the anti-lock braking system is determined to be in an abnormal state based on the anti-lock braking signal, the obtained anti-lock braking signal is unreliable, and the vehicle's current driving condition cannot be accurately determined. In this case, the vehicle's current driving condition can be determined based on signals from other sensors in the vehicle, ensuring safe and stable operation of the vehicle.

[0083] The specific implementation of determining whether the anti-lock braking system is in a normal state based on the anti-lock braking signal of the anti-lock braking system may include: if the anti-lock braking signal can be obtained, or if the obtained anti-lock braking signal is within the reliability verification range, then the anti-lock braking system may be determined to be in a normal state; conversely, if the anti-lock braking signal cannot be obtained and / or the obtained anti-lock braking signal is not within the corresponding signal reliability verification range, then the anti-lock braking system may be determined to be in an abnormal state. It should be noted that in the embodiments of the present invention, the method for determining whether the anti-lock braking system is in a normal state can be designed according to actual needs and is not specifically limited in the embodiments of the present invention.

[0084] In an optional embodiment, the automatic transmission shift control method further includes: when the loss of the anti-lock braking signal is obtained, obtaining the loss time of the anti-lock braking signal; judging whether the loss time reaches a third preset time; if so, determining that the anti-lock braking system is in an abnormal state.

[0085] The loss of the anti-lock signal may be understood as the transmission controller being unable to obtain the anti-lock signal, so that the transmission controller is unable to determine the current driving condition of the vehicle based on the anti-lock signal; the third preset time may be the limit time for the loss of the anti-lock signal.

[0086] It is understandable that when the anti-lock brake signal is lost for a short period of time, the vehicle can still travel normally, and the vehicle's driving condition can be determined based on the last acquired anti-lock brake signal, and the vehicle's driving process can be controlled. However, when the anti-lock brake signal is lost for longer than the loss threshold, i.e., the third preset time, the vehicle's driving condition cannot be determined based on the anti-lock brake signal, and the vehicle's driving process can no longer be controlled based on the anti-lock brake signal.

[0087] In this embodiment, when the transmission controller acquires the anti-lock braking signal in real time, the time when the anti-lock braking signal is currently acquired and the time when the anti-lock braking signal is next acquired can be timed. Therefore, when the anti-lock braking signal cannot be acquired, the time when the anti-lock braking signal is lost can be timed. When the loss time reaches a third preset time and the anti-lock braking signal is still not acquired, it can be considered that an abnormality has occurred in the anti-lock braking system, that is, it can be determined that the anti-lock braking system is in an abnormal state; conversely, if the anti-lock braking signal is acquired again before the anti-lock braking signal is lost for a period of time, it can be determined that the anti-lock braking system is in a normal state.

[0088] Among them, when the anti-lock braking system is in a normal state, the transmission controller can periodically obtain the anti-lock braking signal, and the period for obtaining the anti-lock braking signal is, for example, T. At this time, the third preset time can be k*T, K can be greater than 1. In an exemplary embodiment, k can be 10. In other exemplary embodiments, k can also be other values. The embodiment of the present invention does not specifically limit this.

[0089] S130: When the vehicle is currently traveling on a low-adhesion road surface, control the current gear position of the automatic transmission to remain unchanged.

[0090] Because low-adhesion road conditions occur when a vehicle is traveling on a surface with low friction, the vehicle's drive wheels are prone to slipping, resulting in a high engine speed but a low actual vehicle speed. In these situations, shifting the automatic transmission can cause a momentary loss of power, leading to insufficient power and a potential stall. Therefore, when the vehicle is currently operating on a low-adhesion road, the automatic transmission's current gear can be controlled to remain unchanged, ensuring continuous engine power output to the vehicle's wheels, allowing the vehicle to slowly traverse the low-adhesion road surface.

[0091] This embodiment obtains the vehicle's theoretical speed and the anti-lock braking signal of the anti-lock braking system in the vehicle in real time, and when it is determined that the anti-lock braking system is in a normal state based on the anti-lock braking signal, determines the vehicle's current driving condition based on the vehicle's theoretical speed and the front axle speed of the anti-lock braking system. When the vehicle's current driving condition is a low-adhesion road condition, the current gear of the automatic transmission is controlled to remain unchanged, preventing the vehicle from being stopped due to instantaneous loss of power due to gear changes of the automatic transmission, thereby improving the safety and stability of vehicle operation, and further contributing to an improved driving experience.

[0092] Example 2

[0093] Figure 2 This is a flow chart of an automatic transmission shift control method provided by the second embodiment of the present invention. This embodiment, based on the above embodiment, describes the automatic transmission shift method when the vehicle's current driving condition is a normal road condition. Figure 2 As shown, the method includes:

[0094] S210: Acquire the theoretical vehicle speed and the anti-lock braking signal of the anti-lock braking system in the vehicle in real time.

[0095] S220: When it is determined according to the anti-lock braking signal that the anti-lock braking system is in a normal state, determine the current driving condition of the vehicle according to the theoretical vehicle speed and the front axle speed of the anti-lock braking system.

[0096] S230: When the current driving condition of the vehicle is a low-adhesion road condition, control the current gear position of the automatic transmission to remain unchanged.

[0097] S240: When the current driving condition of the vehicle is a normal road condition, or when the anti-lock braking system is determined to be in an abnormal state according to the anti-lock braking signal, obtain the rotation speed of the engine in the vehicle in real time.

[0098] It is understood that when a vehicle is traveling on a normal road, the road surface has a certain amount of friction, which prevents the vehicle's drive wheels from slipping, allowing the drive wheels to rotate normally and the vehicle's engine to operate at an appropriate speed. In this case, the engine speed can be obtained using a speed sensor installed on the engine, so that the gear position of the automatic transmission can be controlled based on the engine speed.

[0099] It can also be understood that when it is determined that the anti-lock braking system is in an abnormal state based on the anti-lock braking signal, it can be determined that the obtained anti-lock braking signal is no longer reliable. At this time, the current driving condition of the vehicle cannot be accurately determined based on the anti-lock braking signal and the theoretical speed of the vehicle. At this time, the gear of the automatic transmission can also be controlled according to the engine speed.

[0100] S250: Determine a target gear position of the automatic transmission according to the engine speed.

[0101] The engine speed, transmission gear, and vehicle speed must be matched to ensure safe, stable, and economical operation. For example, when the engine's torque is at its maximum, the vehicle's current speed will reach the maximum speed the automatic transmission's current gear can support, requiring an upshift. Conversely, when the engine's torque is at its minimum, the vehicle's current speed will reach the minimum speed the automatic transmission's current gear can support, requiring a downshift. Because the engine's maximum and minimum output torques correspond to different speeds, the engine's current output torque can be determined based on the engine's speed. This, in turn, allows the determination of whether an upshift or downshift is necessary, ultimately determining the target gear for the automatic transmission.

[0102] In an optional embodiment, determining the target gear of the automatic transmission based on the engine speed may include: when the engine speed is greater than a first preset speed, the target gear of the automatic transmission may be controlled to be the next gear of the current gear, that is, if the current gear is L0, the target gear is L0+1; when the engine speed is less than a second preset speed, the target gear of the automatic transmission may be controlled to be the unit before the current gear, that is, if the current gear is L0, the target gear is L0-1.

[0103] S260: Control the current gear position of the automatic transmission to be the target gear position.

[0104] Specifically, after determining the target gear of the automatic transmission based on the engine speed, it is possible to determine whether the target gear of the automatic transmission is the same as the current gear. If the target gear of the automatic transmission is the same as the current gear, no gear shift is required and the automatic transmission maintains the current gear. If the target gear of the automatic transmission is different from the current gear, the automatic transmission gear needs to be shifted. At this time, it is necessary to control the clutch to disengage and change the power transmission route of the gear mechanism corresponding to the current gear of the automatic transmission to the power transmission route of the gear mechanism corresponding to the target gear, thereby achieving the gear shift of the automatic transmission. After the gear shift of the automatic transmission is completed, the clutch can be controlled to engage to provide power for the engine to rotate and ensure normal driving of the vehicle.

[0105] This embodiment obtains the engine speed of the vehicle in real time when determining that the current driving condition of the vehicle is a normal road condition, determines the target gear of the automatic transmission based on the engine speed, and controls the current gear of the automatic transmission to be the target gear, so that the operating gear of the automatic transmission can match the engine speed, thereby meeting the requirements of vehicle operation safety, stability and economy.

[0106] Example 3

[0107] Figure 3 This is a flow chart of an automatic transmission shift control method provided by the third embodiment of the present invention. This embodiment, based on the above embodiment, explains how to determine the current driving condition of the vehicle. Figure 3 As shown, the method includes:

[0108] S310: Acquire the theoretical vehicle speed and the anti-lock braking signal of the anti-lock braking system in the vehicle in real time.

[0109] S320: When it is determined according to the anti-lock braking signal that the anti-lock braking system is in a normal state, determine a current vehicle speed difference according to the front axle speed of the anti-lock braking system at the current moment and the theoretical vehicle speed.

[0110] The current vehicle speed difference may be the difference between the front axle speed of the anti-lock braking system obtained at the current moment and the theoretical vehicle speed. A larger value of the difference indicates a greater difference between the theoretical vehicle speed and the actual vehicle speed.

[0111] S330: Determine a current vehicle speed change rate based on the front axle speed of the anti-lock braking system at the current moment and the front axle speed of the anti-lock braking system at the previous moment.

[0112] Among them, the current vehicle speed change rate can be the difference between the front axle speed of the anti-lock braking system obtained at the current moment and the front axle speed of the anti-lock braking system obtained at the previous moment. The larger the difference is, the faster the vehicle speed change rate is and the higher the vehicle acceleration is.

[0113] S340: Determine the current driving condition of the vehicle based on the current vehicle speed difference and the current vehicle speed change rate.

[0114] Among them, the larger the current speed difference is, the greater the difference between the vehicle's theoretical speed and actual speed is. At the same time, the higher the current speed change rate is, the greater the vehicle's speed change is. When the vehicle's current speed difference is large and the current speed change rate is high, it can be determined that the vehicle's current driving condition may be a low-adhesion road condition; conversely, when the vehicle's current speed difference is small and the current speed change rate is small, it can be determined that the vehicle's current driving condition may be a normal road condition.

[0115] Optionally, the current driving condition of the vehicle is determined based on the current vehicle speed difference and the current vehicle speed change rate, including: judging whether the current vehicle speed difference and the current vehicle speed change rate meet a first preset condition; the first preset condition is that the current vehicle speed difference is greater than the first preset difference, and the current vehicle speed change rate is greater than the first preset change rate; if so, it is determined that the current driving condition of the vehicle is a low-adhesion road condition.

[0116] The first preset difference and the first preset rate of change can be designed based on actual needs and can be determined based on experimental data. Different first preset differences and first preset rates of change can be used for vehicles of different models and weights. In an exemplary embodiment, the first preset difference can be 5 km / h, and the first preset rate of change can be 0.3 km / h. The embodiments of the present invention do not limit the specific values ​​of the first preset difference and the first preset rate of change.

[0117] Specifically, after determining the current vehicle speed difference and the current vehicle speed change rate, it can be judged whether the current vehicle speed difference is greater than the first preset difference, and whether the current vehicle speed change rate is greater than the first preset change rate; if the current vehicle speed difference is greater than the first preset difference, and the current vehicle speed change rate is greater than the first preset change rate, it can be determined that the current driving condition of the vehicle is a low-adhesion road condition.

[0118] Optionally, before determining that the current driving condition of the vehicle is a low-adhesion road condition, it also includes: obtaining a first duration in which the current vehicle speed difference and the current vehicle speed change rate meet a first preset condition; when the first duration is greater than the first preset time, determining that the current driving condition of the vehicle is a low-adhesion road condition.

[0119] The first preset time can be designed according to actual needs, and the embodiment of the present invention does not specifically limit this. In an exemplary embodiment, the first preset time can be 0.1s.

[0120] Specifically, when determining that the current vehicle speed difference is greater than the first preset difference and the current vehicle speed change rate is greater than the first preset change rate, it is also necessary to time the first duration of the current vehicle speed difference being greater than the first preset difference and the current vehicle speed change rate being greater than the first preset change rate; when the first duration is greater than the first preset time, it can be determined that the current vehicle speed difference being greater than the first preset difference and the current vehicle speed change rate being greater than the first preset change rate are not accidental situations, and it can be determined that the current driving condition of the vehicle is a low-adhesion road condition; and when the first duration of the current vehicle speed difference being greater than the first preset difference and the current vehicle speed change rate being greater than the first preset change rate is less than the first preset time, there may be calculation errors, etc., which cause the current vehicle speed difference to be greater than the first preset difference and the current vehicle speed change rate to be greater than the first preset change rate. At this time, the current driving condition of the vehicle can be determined as the condition determined at the previous moment. In this way, by judging whether the current vehicle speed difference is greater than the first preset difference and whether the first duration of the current vehicle speed change rate is greater than the first preset change rate is greater than the first preset time, it is possible to ensure that the current driving condition of the vehicle is determined more accurately, thereby improving the accuracy of the automatic transmission shifting control.

[0121] Optionally, when the vehicle's driving condition also includes normal road conditions, determining the vehicle's current driving condition based on the current vehicle speed difference and the current vehicle speed change rate also includes: judging whether the current vehicle speed difference and the current vehicle speed change rate meet a second preset condition; the second preset condition is that the current vehicle speed difference is less than the second preset difference, and the current vehicle speed change rate is less than the second preset change rate; the second preset difference is less than or equal to the first preset difference, and the second preset change rate is less than or equal to the first preset change rate; if so, determining that the vehicle's current driving condition is a normal adhesion road condition.

[0122] The second preset difference and the second preset rate of change can be designed based on actual needs and can be determined based on experimental data. Vehicles of different models and weights can use different second preset differences and different second preset rates of change. The second preset difference can be the same as or different from the first preset difference, and the second preset rate of change can be the same as or different from the first preset rate of change. The design can be based on actual needs. In an exemplary embodiment, the second preset difference can be 1 km / h, and the second preset rate of change can be 0.1 km / h. The embodiments of the present invention do not limit the specific difference between the second preset difference and the second preset rate of change.

[0123] Specifically, after determining the current vehicle speed difference and the current vehicle speed change rate, it can be judged whether the current vehicle speed difference is less than the second preset difference, and whether the current vehicle speed change rate is less than the first preset change rate; if the current vehicle speed difference is less than the second preset difference, and the current vehicle speed change rate is less than the second preset change rate, it can be determined that the current driving condition of the vehicle is a normal road condition.

[0124] Optionally, before determining that the current driving condition of the vehicle is a normal adhesion road condition, it also includes: obtaining a second duration in which the current vehicle speed difference and the current vehicle speed change rate meet a second preset condition; when the second duration is greater than the second preset time, determining that the current driving condition of the vehicle is a normal adhesion road condition.

[0125] The second preset time can be designed according to actual needs, and the embodiment of the present invention does not specifically limit this. In an exemplary embodiment, the second preset time can be 0.1s.

[0126] Specifically, when it is determined that the current vehicle speed difference is less than the second preset difference, and the current vehicle speed change rate is less than the second preset change rate, it is also necessary to time the second duration of the current vehicle speed difference being less than the second preset difference, and the current vehicle speed change rate being less than the second preset change rate; when the second duration is greater than the second preset time, it can be determined that the current vehicle speed difference being less than the second preset difference, and the current vehicle speed change rate being less than the second preset change rate are not accidental situations, and it can be determined that the current driving condition of the vehicle is a low-adhesion road condition; and when the second duration of the current vehicle speed difference being less than the second preset difference, and the current vehicle speed change rate being less than the second preset change rate is less than the first preset time, there may be calculation errors, etc., which cause the current vehicle speed difference to be less than the second preset difference, and the current vehicle speed change rate to be less than the second preset change rate. At this time, the current driving condition of the vehicle can be determined as the condition determined at the previous moment. In this way, by judging whether the current vehicle speed difference is less than the second preset difference and whether the first duration of the current vehicle speed change rate is less than the second preset change rate is greater than the second preset time, it is possible to ensure that the current driving condition of the vehicle is determined more accurately, thereby improving the accuracy of the automatic transmission shifting control.

[0127] Optionally, determining the current driving condition of the vehicle based on the current vehicle speed difference and the current vehicle speed change rate also includes: if the current vehicle speed difference and the current vehicle speed change rate do not meet the first preset condition, and the current vehicle speed difference and the current vehicle speed change rate do not meet the second preset condition, obtaining the driving condition of the vehicle at the previous moment; and determining the current driving condition of the vehicle as the driving condition of the vehicle at the previous moment.

[0128] Among them, if the current vehicle speed difference and the current vehicle speed change rate do not meet the first preset condition and the second preset condition, the current vehicle speed difference and the current vehicle speed change rate can have a variety of different combinations, for example, the current vehicle speed difference is less than or equal to the first preset difference and greater than or equal to the second preset difference, and the current vehicle speed change rate is less than or equal to the first preset change rate and greater than or equal to the second preset change rate; or, the current vehicle speed difference is less than or equal to the first preset difference and greater than or equal to the second preset difference, and the current vehicle speed change rate is greater than the first preset change rate; or, the current vehicle speed difference is less than or equal to the first preset difference and greater than or equal to the second preset difference. Equal to the second preset difference, and the current vehicle speed change rate is less than the first preset change rate; or, the current vehicle speed difference is greater than the first preset difference, and the current vehicle speed change rate is less than or equal to the first preset change rate and greater than or equal to the second preset change rate; or, the current vehicle speed difference is less than the second preset difference, and the current vehicle speed change rate is less than or equal to the first preset change rate and greater than or equal to the second preset change rate; or, the current vehicle speed difference is less than the second preset difference, and the current vehicle speed change rate is greater than the first preset change rate; or, the current vehicle speed difference is greater than the first preset difference, and the current vehicle speed change rate is less than the second preset change rate.

[0129] Specifically, when the current vehicle speed difference and the current vehicle speed change rate satisfy neither the first preset condition nor the second preset condition, it can be determined that the vehicle driving condition switching condition has not been met, and the vehicle's current driving condition can be determined to be the same as the vehicle's driving condition at the previous moment. For example, if the vehicle's driving condition at the previous moment was a low-adhesion road condition, if the current vehicle speed difference and the current vehicle speed change rate satisfy the first preset condition, it can be determined that the vehicle's current driving condition is still a low-adhesion road condition. If the current vehicle speed difference and the current vehicle speed change rate no longer satisfy the first preset condition and also do not satisfy the second preset condition, it can be determined that the vehicle's current driving condition is about to change but has not completely changed. In this case, to ensure smooth vehicle driving, the vehicle's current driving condition can continue to be determined as a low-adhesion road condition. If the current vehicle speed difference and the current vehicle speed change rate no longer satisfy the first preset condition but satisfy the second preset condition, it can be determined that the vehicle's current driving condition has changed, i.e., the vehicle's current driving condition can be determined to have switched from a low-adhesion road condition to a normal road condition. For the case where the vehicle's driving condition at the previous moment is a normal road driving condition, a determination method similar to the above is used. For details, please refer to the above description and will not be repeated here.

[0130] S350: When the vehicle is currently operating on a low-adhesion road surface, control the current gear position of the automatic transmission to remain unchanged.

[0131] S360: When the current driving condition of the vehicle is a normal road condition, obtain the rotation speed of the engine in the vehicle in real time.

[0132] S370: Determine a target gear position of the automatic transmission according to the engine speed.

[0133] S380: Control the current gear position of the automatic transmission to be the target gear position.

[0134] This embodiment determines the current vehicle speed difference and the current vehicle speed change rate respectively, so as to accurately determine the current driving condition of the vehicle based on the current vehicle speed difference and the current vehicle speed change rate, thereby being able to perform targeted control on the shifting mode of the automatic transmission according to the current driving condition of the vehicle, thereby ensuring that the vehicle can operate safely and stably.

[0135] Example 4

[0136] Figure 4 This is a flow chart of an automatic transmission shift control method provided by the fourth embodiment of the present invention. Based on the above embodiment, this embodiment describes how to determine the theoretical speed of the vehicle. Figure 4 As shown, the method includes:

[0137] S410: Acquire the output shaft speed of the automatic transmission in real time.

[0138] The output shaft speed of the automatic transmission can be obtained by using a speed sensor provided at the output shaft of the automatic transmission.

[0139] S420: Determine the theoretical speed of the vehicle according to the output shaft speed of the automatic transmission.

[0140] Specifically, since the output shaft of the automatic transmission is usually connected to the drive shaft of the vehicle, the output shaft speed of the automatic transmission can be used to characterize the theoretical vehicle speed during the vehicle's driving process, that is, the output shaft speed of the automatic transmission can be converted into the theoretical vehicle speed based on the corresponding proportional relationship.

[0141] Optionally, determining the theoretical speed of the vehicle according to the output shaft speed of the automatic transmission includes: calculating the theoretical speed of the vehicle based on a first calculation formula according to the output shaft speed of the automatic transmission.

[0142] Among them, the first calculation formula is:

[0143]

[0144] Among them, V l is the theoretical speed of the vehicle, N is the output shaft speed of the automatic transmission, i g is the main reduction ratio of the automatic transmission, r is the tire radius of the vehicle, and k is the vehicle speed calculation coefficient. k can be related to the conversion rate of each parameter in the first calculation formula. For example, k can be 0.377.

[0145] S430: Acquire an anti-lock braking signal of an anti-lock braking system in the vehicle in real time.

[0146] S440: When it is determined according to the anti-lock braking signal that the anti-lock braking system is in a normal state, determine the current driving condition of the vehicle according to the theoretical vehicle speed and the front axle speed of the anti-lock braking system.

[0147] S450: When the vehicle is currently operating on a low-adhesion road surface, control the current gear position of the automatic transmission to remain unchanged.

[0148] This embodiment obtains the output shaft speed of the automatic transmission connected to the vehicle's drive shaft, and determines the vehicle's theoretical speed based on the output speed of the automatic transmission and other known parameters, so as to accurately determine the vehicle's current driving condition based on the vehicle's theoretical speed and the front axle speed of the anti-lock braking system, thereby enabling targeted control of the automatic transmission's shifting mode based on the vehicle's current driving condition, thereby ensuring the vehicle's safe and stable operation.

[0149] Example 5

[0150] Figure 5 This is a flowchart of an automatic transmission shift control method provided by the fifth embodiment of the present invention. Based on the above embodiment, this embodiment describes the implementation method of adjusting the automatic transmission gear according to the engine speed. Figure 5 As shown, the method includes:

[0151] S510: Acquire the theoretical vehicle speed and the anti-lock braking signal of the anti-lock braking system in the vehicle in real time.

[0152] S520, when the anti-lock braking system is in a normal state according to the anti-lock braking signal, the current driving condition of the vehicle is determined based on the theoretical speed of the vehicle and the front axle speed of the anti-lock braking system.

[0153] S530: When the current driving condition of the vehicle is a low-adhesion road condition, control the current gear position of the automatic transmission to remain unchanged.

[0154] S540: Obtain the speed of the engine in the vehicle in real time.

[0155] The rotation speed of the engine in the vehicle can be obtained by using a rotation speed sensor provided at the engine.

[0156] S550: Determine whether the current engine speed is within a preset speed range; if not, execute S560.

[0157] S560: Adjust the current gear of the automatic transmission according to a preset gear change amount.

[0158] During engine operation, the engine must rotate within a predetermined speed range. Exceeding this speed range can cause abnormal engine operation or even damage. Therefore, during the period when the current gear of the automatic transmission remains constant, it is necessary to obtain the engine speed in real time and determine whether the current engine speed exceeds the predetermined speed range. If the current engine speed exceeds the predetermined speed range, it can be determined that the current gear of the transmission no longer matches the engine speed. In this case, the current gear of the automatic transmission can be adjusted by a predetermined gear change amount. For example, if the current gear of the automatic transmission is L0 and the predetermined gear change amount is ΔL, the current gear of the automatic transmission can be adjusted from L0 to L0+ΔL to provide a certain degree of protection for engine operation.

[0159] In other optional embodiments, if the current speed of the engine is within a preset speed range, the automatic transmission can continue to be controlled to maintain the current gear position unchanged to meet the power requirements of low-adhesion roads.

[0160] It is understood that the preset gear change amount can be a positive value or a negative value, and can be specifically determined according to the speed range to which the current speed of the engine belongs. In an exemplary embodiment, the preset gear change amount can be -1 or +1.

[0161] Optionally, the current gear of the automatic transmission is adjusted by a preset gear change, including: when the current speed of the engine is greater than the upper limit of the preset speed range, increasing the current gear of the automatic transmission by a preset gear increment; when the current speed of the engine is less than the lower limit of the preset speed range, reducing the current gear of the automatic transmission by a preset gear reduction.

[0162] The upper limit of the preset speed range may be the maximum protection speed of the engine, and the lower limit of the preset speed range may be the minimum protection speed of the engine. In this case, when the current speed of the engine is greater than the maximum protection speed of the engine, the current gear of the automatic transmission may be increased by a preset gear increment. For example, the current gear of the automatic transmission may be controlled from L0 to L0+1, so that the gear of the automatic transmission can match the speed of the engine. When the current speed of the engine is less than the minimum protection speed of the engine, the current gear of the automatic transmission may be decreased by a preset gear reduction. For example, the current gear of the automatic transmission may be controlled from L0 to L0-1, so that the gear of the automatic transmission can match the speed of the engine.

[0163] This embodiment obtains the engine speed and determines whether the current engine speed is within a preset speed range. When the current engine speed is not within the preset speed range, the current gear of the automatic transmission can be adjusted according to the preset gear change amount, so that the current gear of the automatic transmission can match the current engine speed, preventing the engine speed from being too high or too low, which affects the engine's operating life, thereby further improving the safety and stability of vehicle operation.

[0164] Example 6

[0165] Figure 6 Schematic diagram of the structure of an automatic transmission shift control device provided by the sixth embodiment of the present invention. Figure 6 As shown, the device includes:

[0166] The signal acquisition module 61 is used to obtain the theoretical vehicle speed and the anti-lock braking signal of the anti-lock braking system in the vehicle in real time; the anti-lock braking signal at least includes the front axle speed of the anti-lock braking system;

[0167] The operating condition determination module 62 is configured to determine the current driving condition of the vehicle based on the theoretical vehicle speed and the front axle speed of the anti-lock braking system when the anti-lock braking system is determined to be in a normal state according to the anti-lock braking signal; the driving condition of the vehicle at least includes a low-adhesion road condition;

[0168] The gear control module 63 is used to control the current gear of the automatic transmission to remain unchanged when the current driving condition of the vehicle is a low-adhesion road condition.

[0169] Optionally, the vehicle's driving conditions also include normal road conditions; and the automatic transmission shift control device further includes:

[0170] The engine speed acquisition module is used to obtain the engine speed of the vehicle in real time when the current driving condition of the vehicle is a normal road condition;

[0171] A target gear determination module, configured to determine a target gear of the automatic transmission according to the engine speed;

[0172] The gear control module 63 is further configured to control the current gear of the automatic transmission to be the target gear.

[0173] Optionally, the operating condition determination module 62 includes:

[0174] a vehicle speed difference determination unit, configured to determine a current vehicle speed difference based on the front axle speed of the anti-lock braking system at a current moment and the theoretical vehicle speed;

[0175] a vehicle speed change rate determination module, configured to determine a current vehicle speed change rate based on a front axle speed of the anti-lock braking system at a current moment and a front axle speed of the anti-lock braking system at a previous moment;

[0176] The operating condition determination unit is used to determine the current driving condition of the vehicle based on the current vehicle speed difference and the current vehicle speed change rate.

[0177] Optionally, the operating condition determination unit is specifically configured to:

[0178] Determine whether the current vehicle speed difference and the current vehicle speed change rate meet a first preset condition; the first preset condition is that the current vehicle speed difference is greater than the first preset difference and the current vehicle speed change rate is greater than the first preset change rate;

[0179] If so, it is determined that the current driving condition of the vehicle is a low-adhesion road condition.

[0180] Optionally, the operating condition determination unit is further configured to:

[0181] Before determining that the current driving condition of the vehicle is the low-adhesion road condition, obtaining a first duration in which the current vehicle speed difference and the current vehicle speed change rate meet a first preset condition;

[0182] When the first duration is greater than a first preset time, it is determined that the current driving condition of the vehicle is a low-adhesion road condition.

[0183] Optionally, when the vehicle's driving operating condition also includes a normal road operating condition, the operating condition determination unit is further specifically configured to:

[0184] Determining whether the current vehicle speed difference and the current vehicle speed change rate meet a second preset condition; the second preset condition being that the current vehicle speed difference is less than the second preset difference and the current vehicle speed change rate is less than the second preset change rate; the second preset difference is less than or equal to the first preset difference and the second preset change rate is less than or equal to the first preset change rate;

[0185] If so, it is determined that the current driving condition of the vehicle is a normal adhesion road condition.

[0186] Optionally, the operating condition determination unit is further configured to:

[0187] Before determining that the current driving condition of the vehicle is a normal adhesion road condition, obtaining a second duration during which the current vehicle speed difference and the current vehicle speed change rate meet a second preset condition;

[0188] When the second duration is greater than the second preset time, it is determined that the current driving condition of the vehicle is a normal adhesion road condition.

[0189] Optionally, the operating condition determination unit is further configured to:

[0190] If the current vehicle speed difference and the current vehicle speed change rate do not meet the first preset condition, and the current vehicle speed difference and the current vehicle speed change rate do not meet the second preset condition, then obtaining the vehicle's driving condition at the previous moment;

[0191] The current driving condition of the vehicle is determined as the driving condition of the vehicle at the previous moment.

[0192] Optionally, the signal acquisition module 61 includes:

[0193] An output shaft speed acquisition unit, used to acquire the output shaft speed of the automatic transmission in real time;

[0194] The theoretical vehicle speed determination unit is used to determine the theoretical vehicle speed of the vehicle according to the output shaft speed of the automatic transmission.

[0195] Optionally, the theoretical vehicle speed determination unit is specifically configured to:

[0196] According to the output shaft speed of the automatic transmission, the theoretical speed of the vehicle is calculated based on the first calculation formula; the first calculation formula is:

[0197]

[0198] Among them, V l is the theoretical speed of the vehicle, N is the output shaft speed of the automatic transmission, i g is the main reduction ratio of the automatic transmission, r is the tire radius of the vehicle, and k is the vehicle speed calculation coefficient.

[0199] Optionally, the automatic transmission shift control device further includes:

[0200] An engine speed acquisition module is used to acquire the engine speed of the vehicle in real time when it is determined that the anti-lock braking system is in an abnormal state according to the anti-lock braking signal;

[0201] A target gear determination module, configured to determine a target gear of the automatic transmission according to the engine speed;

[0202] The gear control module 63 is further configured to control the current gear of the automatic transmission to be the target gear.

[0203] Optionally, the automatic transmission shift control device further includes:

[0204] A loss time acquisition module is used to obtain the loss time of the anti-lock braking signal when the loss of the anti-lock braking signal is obtained;

[0205] A loss time determination module, configured to determine whether the loss time reaches a third preset time;

[0206] The system state determination module is configured to determine that the anti-lock braking system is in an abnormal state when the loss time reaches a third preset time.

[0207] Optionally, the automatic transmission shift control device further includes:

[0208] Engine speed acquisition module, used to obtain the engine speed in real time;

[0209] A speed determination module is used to determine whether the current speed of the engine is within a preset speed range;

[0210] The gear adjustment module is used to adjust the current gear of the automatic transmission by a preset gear change amount if the current speed of the engine is not within a preset speed range.

[0211] Optionally, the gear adjustment module is specifically used to:

[0212] When the current speed of the engine is greater than an upper limit of a preset speed range, increasing the current gear of the automatic transmission by a preset gear increment;

[0213] When the current speed of the engine is less than a lower limit value of a preset speed range, the current gear of the automatic transmission is reduced by a preset gear reduction amount.

[0214] The automatic transmission gear control device provided in the embodiment of the present invention can execute the automatic transmission shift control method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method. The similarities can be referred to the above description and will not be repeated here.

[0215] Example 7

[0216] This embodiment provides a vehicle, which includes an engine, an engine controller, an automatic transmission and an anti-lock braking system; the engine controller is used to control the operating state of the engine; the automatic transmission includes a transmission controller and a transmission body; the transmission body is mechanically connected to the engine; the transmission controller is connected to the engine controller and the anti-lock braking system respectively, and the transmission controller is used to execute the automatic transmission shift control method of any embodiment of the present invention to control the operating state of the transmission body.

[0217] It is understood that the connection method of the transmission controller, the engine controller and the anti-lock braking system can be designed according to actual needs, and the embodiment of the present invention does not specifically limit this. In an exemplary embodiment, the transmission controller can be communicated with the engine controller and the anti-lock braking system via a bus.

[0218] The transmission controller in the vehicle provided in the embodiment of the present invention can execute the automatic transmission shift control method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method. The similarities can be referred to the above description and will not be repeated here.

[0219] Example 8

[0220] This embodiment provides a computer-readable storage medium storing computer instructions. The computer instructions are used to enable a processor to implement the automatic transmission shift control method of any embodiment of the present invention when executed.

[0221] Wherein, computer readable storage medium can be tangible medium, and it can contain or store for use for instruction execution system, device or equipment or the computer program used in combination with instruction execution system, device or equipment.Computer readable storage medium can include but not limited to electronic, magnetic, optical, electromagnetic, infrared or semiconductor system, device or equipment, or any suitable combination of the above.Alternatively, computer readable storage medium can be machine readable signal medium.More specific examples of machine readable storage medium can include electrical connection based on one or more lines, portable computer disk, hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device or any suitable combination of the above.

[0222] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved. This is not limited herein.

[0223] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A method for controlling automatic transmission shifting, applied to a vehicle, characterized in that: include: Acquiring in real time the theoretical speed of the vehicle and an anti-lock braking signal of an anti-lock braking system in the vehicle; The anti-lock braking signal at least includes the front axle speed of the anti-lock braking system; When it is determined according to the anti-lock braking signal that the anti-lock braking system is in a normal state, determining a current vehicle speed difference according to the front axle speed of the anti-lock braking system at a current moment and the theoretical vehicle speed of the vehicle; determining a current vehicle speed change rate based on a front axle speed of the anti-lock braking system at a current moment and a front axle speed of the anti-lock braking system at a previous moment; Determining whether the current vehicle speed difference and the current vehicle speed change rate meet a first preset condition; the first preset condition being that the current vehicle speed difference is greater than a first preset difference and the current vehicle speed change rate is greater than a first preset change rate; If yes, obtaining a first duration in which the current vehicle speed difference and the current vehicle speed change rate meet a first preset condition; When the first duration is greater than a first preset time, determining that the current driving condition of the vehicle is a low-adhesion road condition; When the current driving condition of the vehicle is the low-adhesion road condition, the current gear position of the automatic transmission is controlled to remain unchanged.

2. The automatic transmission shift control method according to claim 1, characterized in that: The vehicle's driving condition also includes a normal adhesion road condition; the automatic transmission shift control method further includes: When the current driving condition of the vehicle is the normal adhesion road condition, obtaining the rotation speed of the engine in the vehicle in real time; determining a target gear position of the automatic transmission according to a rotational speed of the engine; The current gear position of the automatic transmission is controlled to be the target gear position.

3. The automatic transmission shift control method according to claim 1, wherein: The vehicle's driving condition also includes a normal adhesion road condition; Determining the current driving condition of the vehicle according to the current vehicle speed difference and the current vehicle speed change rate further includes: determining whether the current vehicle speed difference and the current vehicle speed change rate satisfy a second preset condition; the second preset condition being that the current vehicle speed difference is less than the second preset difference and the current vehicle speed change rate is less than the second preset change rate; the second preset difference is less than or equal to the first preset difference and the second preset change rate is less than or equal to the first preset change rate; If so, it is determined that the current driving condition of the vehicle is a normal adhesion road condition.

4. The automatic transmission shift control method according to claim 3, characterized in that: Before determining that the current driving condition of the vehicle is a normal adhesion road condition, the method further includes: Obtaining a second duration during which the current vehicle speed difference and the current vehicle speed change rate meet a second preset condition; When the second duration is greater than a second preset time, it is determined that the current driving condition of the vehicle is a normal adhesion road condition.

5. The automatic transmission shift control method according to claim 3, characterized in that: Determining the current driving condition of the vehicle according to the current vehicle speed difference and the current vehicle speed change rate further includes: If the current vehicle speed difference and the current vehicle speed change rate do not satisfy the first preset condition, and the current vehicle speed difference and the current vehicle speed change rate do not satisfy the second preset condition, obtaining the driving condition of the vehicle at the previous moment; The current driving condition of the vehicle is determined as the driving condition of the vehicle at the previous moment.

6. The automatic transmission shift control method according to claim 1, wherein: Obtaining the theoretical speed of the vehicle, including: acquiring the output shaft speed of the automatic transmission in real time; The theoretical vehicle speed is determined according to the output shaft speed of the automatic transmission.

7. The automatic transmission shift control method according to claim 6, characterized in that: Determining the theoretical speed of the vehicle according to the output shaft speed of the automatic transmission includes: The theoretical speed of the vehicle is calculated according to the output shaft speed of the automatic transmission based on a first calculation formula; the first calculation formula is: ； Among them, V l is the theoretical speed of the vehicle, N is the output shaft speed of the automatic transmission, i g is the final reduction ratio of the automatic transmission, r is the tire radius of the vehicle, and k is the vehicle speed calculation coefficient.

8. The automatic transmission shift control method according to claim 1, wherein: Also includes: When it is determined according to the anti-lock braking signal that the anti-lock braking system is in an abnormal state, obtaining the speed of the engine in the vehicle in real time; determining a target gear position of the automatic transmission according to a rotational speed of the engine; The current gear of the automatic transmission is controlled to be the target gear.

9. The automatic transmission shift control method according to claim 8, characterized in that: Also includes: When the loss of the anti-lock braking signal is obtained, obtaining the loss time of the anti-lock braking signal; Determining whether the loss time reaches a third preset time; If so, it is determined that the anti-lock braking system is in an abnormal state.

10. The automatic transmission shift control method according to claim 1, wherein: Also includes: obtaining the speed of the engine in the vehicle in real time; determining whether the current speed of the engine is within a preset speed range; If not, the current gear of the automatic transmission is adjusted by a preset gear change amount.

11. The automatic transmission shift control method according to claim 10, wherein: Adjusting the current gear of the automatic transmission by a preset gear change amount includes: When the current speed of the engine is greater than an upper limit of the preset speed range, increasing the current gear of the automatic transmission by a preset gear increment; When the current speed of the engine is less than a lower limit of the preset speed range, the current gear of the automatic transmission is reduced by a preset gear reduction amount.

12. An automatic transmission shift control device, used in a vehicle, characterized in that: include: a signal acquisition module, configured to acquire in real time the theoretical speed of the vehicle and an anti-lock braking signal of an anti-lock braking system in the vehicle; the anti-lock braking signal at least including the front axle speed of the anti-lock braking system; A working condition determination module, comprising a vehicle speed difference determination unit, a vehicle speed change rate determination module, and a working condition determination unit; The vehicle speed difference determination unit is configured to determine a current vehicle speed difference based on the front axle speed of the anti-lock braking system and the theoretical vehicle speed at the current moment when it is determined that the anti-lock braking system is in a normal state according to the anti-lock braking signal; The vehicle speed change rate determination module is used to determine the current vehicle speed change rate based on the front axle vehicle speed of the anti-lock braking system at the current moment and the front axle vehicle speed of the anti-lock braking system at the previous moment; The operating condition determination unit is used to determine whether the current vehicle speed difference and the current vehicle speed change rate meet a first preset condition; the first preset condition is that the current vehicle speed difference is greater than the first preset difference, and the current vehicle speed change rate is greater than the first preset change rate; If yes, obtaining a first duration in which the current vehicle speed difference and the current vehicle speed change rate meet a first preset condition; When the first duration is greater than a first preset time, determining that the current driving condition of the vehicle is a low-adhesion road condition; The gear control module is used to control the current gear of the automatic transmission to remain unchanged when the current driving condition of the vehicle is the low-adhesion road condition.

13. A vehicle, characterized in that: include: engines, engine controllers, automatic transmissions, and anti-lock braking systems; The engine controller is used to control the operating state of the engine; The automatic transmission comprises a transmission controller and a transmission body; the transmission body is mechanically connected to the engine; The transmission controller is connected to the engine controller and the anti-lock braking system respectively, and is used to execute the automatic transmission shift control method according to any one of claims 1 to 11 to control the operating state of the transmission body.

14. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the automatic transmission shift control method according to any one of claims 1 to 11 when executed.

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