Method and system for identifying operating condition of vehicle under traction control, and vehicle

Abstract

Disclosed in the present application are a method and system for identifying an operating condition of a vehicle under traction control, and a vehicle. In the present application, a wheel speed difference and a vehicle speed are determined, so as to identify that a vehicle is currently in a curve operating condition; a maximum braking force difference and a vehicle speed are determined, so as to identify that the vehicle is currently in an operating condition of driving in an opposite direction; a driving gradient and a vehicle speed are determined, so as to identify that the vehicle is currently in a ramp operating condition; and a current longitudinal friction coefficient potential, a longitudinal friction coefficient and a lateral friction coefficient are determined, so as to identify a friction coefficient utilization state.

Description

Traction control vehicle condition identification methods, systems and vehicles

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202411219574.8, filed on September 2, 2024, entitled “Vehicle Condition Identification Method, System and Vehicle for Traction Control”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the technical field of automobiles, specifically to a vehicle operating condition identification method, system, and vehicle for traction control. Background Technology

[0004] With the advancement of intelligent and electric vehicles, most vehicles are now equipped with Integrated Braking Control (IBC), which uses hydraulic brake lines to achieve braking. Traction control is one of the essential functions of IBC. Its main function is to promptly control the vehicle when wheel slippage occurs, ensuring stability and safety during vehicle operation. In real-world driving environments, road conditions are often complex, requiring different control methods and levels. When traction control is in operation, it employs different control methods for different road surfaces and conditions, intervening in the vehicle with a more rational approach to ensure more effective control. Therefore, identifying the vehicle's current operating condition is crucial. Summary of the Invention

[0005] This application aims to at least solve one of the technical problems existing in the prior art. To this end, this application provides a vehicle operating condition identification method for traction control. When the vehicle is under traction control, the method determines the actual operating condition of the vehicle, facilitating different control modes for the vehicle, ensuring the effectiveness and rationality of the control, and enabling the traction control system to exert sufficient power.

[0006] A vehicle operating condition identification method for traction control according to a first aspect of the embodiments of this application includes:

[0007] Obtain vehicle speed, wheel speed difference between the left and right wheels of the drive axle, maximum braking force difference between the left and right wheels of each axle, driving gradient, current potential longitudinal friction coefficient, longitudinal friction coefficient, and lateral friction coefficient;

[0008] When the wheel speed difference is greater than a first preset threshold and the vehicle speed is greater than a second preset threshold, it is determined that the current vehicle is in a curve condition.

[0009] When the maximum braking force difference is greater than the third preset threshold and the vehicle speed is less than the fourth preset threshold, it is determined that the current vehicle is in a two-way working condition.

[0010] When the driving gradient is greater than the fifth preset threshold and the vehicle speed is less than the sixth preset threshold, it is determined that the current vehicle is in a slope condition.

[0011] When the potential of the current longitudinal friction coefficient is less than the seventh preset threshold and the difference between the longitudinal friction coefficient and the potential of the current longitudinal friction coefficient is greater than the eighth preset threshold, it is determined that the longitudinal friction coefficient is overutilized.

[0012] If the difference between the longitudinal friction coefficient and the potential of the current longitudinal friction coefficient is greater than a ninth preset threshold and the lateral friction coefficient is greater than a tenth preset threshold, then it is determined that the longitudinal friction coefficient is underutilized.

[0013] The vehicle operating condition identification method for traction control according to the embodiments of this application has at least the following beneficial effects:

[0014] This application identifies the current vehicle's operating condition as a curve by judging wheel speed difference and vehicle speed, identifies the current vehicle's operating condition as a split-drive vehicle by judging maximum braking force difference and vehicle speed, identifies the current vehicle's operating condition as a slope by judging driving gradient and vehicle speed, and identifies the friction coefficient utilization state by judging the current longitudinal friction coefficient potential, longitudinal friction coefficient, and lateral friction coefficient. This application identifies the necessary operating conditions in the traction control system, ensuring timely judgment when the operating conditions are met and ensuring that the corresponding control mode is subsequently adopted.

[0015] According to some embodiments of this application, obtaining the vehicle speed, the wheel speed difference between the left and right wheels of the drive axle, the maximum braking force difference between the left and right wheels of each axle, the driving gradient, the current potential longitudinal friction coefficient, the longitudinal friction coefficient, and the lateral friction coefficient includes:

[0016] The wheel speeds of the left and right wheels of the drive shaft are detected, the difference is calculated, and the absolute value is taken to obtain the wheel speed difference.

[0017] According to some embodiments of this application, obtaining the vehicle speed, the wheel speed difference between the left and right wheels of the drive axle, the maximum braking force difference between the left and right wheels of each axle, the driving gradient, the current potential longitudinal friction coefficient, the longitudinal friction coefficient, and the lateral friction coefficient includes:

[0018] The braking force of the left and right wheels of each axle is detected, and the difference between the braking force of the left and right wheels of each axle is calculated. The absolute values ​​are then compared to obtain the maximum braking force difference.

[0019] According to some embodiments of this application, obtaining the vehicle speed, the wheel speed difference between the left and right wheels of the drive axle, the maximum braking force difference between the left and right wheels of each axle, the driving gradient, the current potential longitudinal friction coefficient, the longitudinal friction coefficient, and the lateral friction coefficient includes:

[0020] The driving gradient is calculated using Formula 1.

[0021] Formula 1 is: i = (ax - a) / g, where ax is the value of the inertial acceleration sensor, a is the actual acceleration of the vehicle, g is the acceleration due to gravity, and i is the driving slope.

[0022] According to some embodiments of this application, obtaining the vehicle speed, the wheel speed difference between the left and right wheels of the drive axle, the maximum braking force difference between the left and right wheels of each axle, the driving gradient, the current potential longitudinal friction coefficient, the longitudinal friction coefficient, and the lateral friction coefficient includes:

[0023] The residual friction coefficient is calculated using Formula 2.

[0024] The current longitudinal friction coefficient potential is obtained by a preset relationship between the remaining friction coefficient and the longitudinal friction coefficient potential.

[0025] Formula 2 is: muSquare = muEst 2 -muY 2 , muEst is the current estimated friction coefficient, muY is the lateral friction coefficient, and muSquare is the residual friction coefficient.

[0026] According to some embodiments of this application, the calculation of the residual friction coefficient using Formula 2 includes:

[0027] The intermediate variables are calculated using Formula 3;

[0028] The current estimated friction coefficient is obtained through a preset relationship between intermediate variables and the estimated friction coefficient;

[0029] Formula 3 is: S = (0.2a) x ) 2 +(0.2a y ) 2 a x For longitudinal acceleration, a y Let S be the lateral acceleration, and S be an intermediate variable.

[0030] According to some embodiments of this application, determining that the longitudinal friction coefficient utilization is too high when the current longitudinal friction coefficient potential is less than a seventh preset threshold and the difference between the longitudinal friction coefficient and the current longitudinal friction coefficient potential is greater than an eighth preset threshold includes:

[0031] The difference between the longitudinal friction coefficient and the potential of the current longitudinal friction coefficient is obtained by subtracting the potential of the current longitudinal friction coefficient from the longitudinal friction coefficient.

[0032] According to some embodiments of this application, the step of determining that the longitudinal friction coefficient is underutilized when the difference between the longitudinal friction coefficient and the current potential longitudinal friction coefficient is greater than a ninth preset threshold and the lateral friction coefficient is greater than a tenth preset threshold includes:

[0033] The difference between the potential longitudinal friction coefficient and the potential longitudinal friction coefficient is obtained by subtracting the potential longitudinal friction coefficient from the potential potential.

[0034] According to some embodiments of this application, the step of determining that the current vehicle is in a driving condition when the maximum braking force difference is greater than a third preset threshold and the vehicle speed is less than a fourth preset threshold further includes:

[0035] Check the stability of the wheels on each axle;

[0036] When the maximum braking force difference is greater than the third preset threshold, the vehicle speed is less than the fourth preset threshold, and each axle has single-wheel stability, it is determined that the current vehicle is in a two-wheel driving condition.

[0037] A vehicle operating condition recognition system for traction control according to a second aspect of an embodiment of this application includes:

[0038] The calculation and acquisition module is used to obtain vehicle speed, wheel speed difference between the left and right wheels of the drive axle, maximum braking force difference between the left and right wheels of each axle, driving gradient, current potential longitudinal friction coefficient, longitudinal friction coefficient, and lateral friction coefficient.

[0039] The judgment module is used to determine that the vehicle is currently in a curve condition when the wheel speed difference is greater than a first preset threshold and the vehicle speed is greater than a second preset threshold; to determine that the vehicle is currently in a driving condition when the maximum braking force difference is greater than a third preset threshold and the vehicle speed is less than a fourth preset threshold; to determine that the vehicle is currently in a slope condition when the driving gradient is greater than a fifth preset threshold and the vehicle speed is less than a sixth preset threshold; to determine that the longitudinal friction coefficient is overutilized when the current longitudinal friction coefficient potential is less than a seventh preset threshold and the difference between the longitudinal friction coefficient and the current longitudinal friction coefficient potential is greater than an eighth preset threshold; and to determine that the longitudinal friction coefficient is underutilized when the difference between the longitudinal friction coefficient and the current longitudinal friction coefficient potential is greater than a ninth preset threshold and the lateral friction coefficient is greater than a tenth preset threshold.

[0040] A vehicle according to a third aspect of an embodiment of this application includes the aforementioned traction control vehicle condition recognition system.

[0041] According to a fourth aspect of the present application, a computer-readable storage medium stores computer-executable instructions for causing a computer to perform the vehicle condition identification method for traction control.

[0042] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing the application. Attached Figure Description

[0043] The present application will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0044] Figure 1 is a flowchart of the vehicle operating condition identification method for traction control in this application;

[0045] Figure 2 is a linear schematic diagram of the preset relationship between the residual friction coefficient and the longitudinal friction coefficient potential of this application;

[0046] Figure 3 is a linear schematic diagram of the preset relationship between the intermediate variables and the estimated friction coefficient in this application;

[0047] Figure 4 is a schematic diagram of the working conditions that the traction control system of this application needs to identify;

[0048] Figure 5 is a schematic diagram of the specific identification process steps for the curved working condition in this application;

[0049] Figure 6 is a schematic diagram of the specific identification process steps for the split-type working condition in this application;

[0050] Figure 7 is a schematic diagram of the specific identification process steps for the ramp working conditions in this application;

[0051] Figure 8 is a schematic diagram of the specific identification process steps for the utilization state of the friction coefficient in this application. Embodiments of the present invention

[0052] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0053] In the description of this application, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, 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, and therefore should not be construed as a limitation of this application.

[0054] In the description of this application, "multiple" refers to two or more. The use of "first" and "second" is for the purpose of distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features indicated, or the order in which the technical features are indicated.

[0055] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0056] The technical solution of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are some embodiments of this application, not all embodiments.

[0057] In real-world driving environments, road conditions are often complex, and different conditions require different control methods and levels. Therefore, identifying the current operating condition of a vehicle is crucial. This application proposes a vehicle operating condition identification method applicable to traction control of redundant braking systems. When a vehicle is under traction control, the method determines the actual operating condition of the vehicle, facilitating different control methods and ensuring the effectiveness and rationality of the control, so that the traction control system can exert sufficient power.

[0058] As shown in Figure 1, the vehicle operating condition identification method for traction control in this application includes, but is not limited to, the following steps:

[0059] Step S100: Obtain vehicle speed, wheel speed difference between the left and right wheels of the drive axle, maximum braking force difference between the left and right wheels of each axle, driving gradient, current potential longitudinal friction coefficient, longitudinal friction coefficient, and lateral friction coefficient;

[0060] Step S200: When the wheel speed difference is greater than the first preset threshold and the vehicle speed is greater than the second preset threshold, it is determined that the current vehicle is in a curve condition;

[0061] Step S300: When the maximum braking force difference is greater than the third preset threshold and the vehicle speed is less than the fourth preset threshold, it is determined that the current vehicle is in a two-way working condition.

[0062] Step S400: When the driving gradient is greater than the fifth preset threshold and the vehicle speed is less than the sixth preset threshold, it is determined that the current vehicle is in a slope condition.

[0063] Step S500: When the current potential of the longitudinal friction coefficient is less than the seventh preset threshold and the difference between the longitudinal friction coefficient and the current potential of the longitudinal friction coefficient is greater than the eighth preset threshold, it is determined that the longitudinal friction coefficient is overutilized.

[0064] Step S600: When the difference between the longitudinal friction coefficient and the current potential longitudinal friction coefficient is greater than the ninth preset threshold and the lateral friction coefficient is greater than the tenth preset threshold, it is determined that the longitudinal friction coefficient is underutilized.

[0065] This application identifies the current vehicle's condition as a curve by judging wheel speed difference and vehicle speed, identifies the current vehicle's condition as a driving-in-a-row by judging maximum braking force difference and vehicle speed, identifies the current vehicle's condition as a slope by judging driving gradient and vehicle speed, and identifies the friction coefficient utilization state by judging the current longitudinal friction coefficient potential, longitudinal friction coefficient, and lateral friction coefficient. This application identifies the necessary operating conditions in the traction control system, ensuring timely judgment when the operating conditions are met and ensuring that the corresponding control method is subsequently adopted.

[0066] In step S100, the wheel speed difference is calculated by detecting the wheel speeds of the left and right wheels of the drive shaft, subtracting the wheel speeds of the left and right wheels and taking the absolute value to obtain the wheel speed difference. The wheel speeds of the left and right wheels of the drive shaft can be detected in real time by a speed sensor, while the vehicle speed is detected by a total speed sensor of the vehicle.

[0067] In step S100, the maximum braking force difference is calculated by detecting the braking force of the left and right wheels of each axle, subtracting the braking force of the left and right wheels of each axle, comparing the absolute values, and taking the maximum value to obtain the maximum braking force difference. The braking force of the left and right wheels of each axle can be detected by the real-time wheel speed through a torque sensor.

[0068] In step S100, the driving slope is calculated using Formula 1, where Formula 1 is: i = (ax - a) / g, ax is the value of the inertial acceleration sensor, a is the actual acceleration of the vehicle, g is the gravitational acceleration, and i is the driving slope.

[0069] In step S100, the calculation of the current longitudinal friction coefficient potential is first performed by calculating the remaining friction coefficient using Formula 2, and then by obtaining the current longitudinal friction coefficient potential through the preset relationship between the remaining friction coefficient and the longitudinal friction coefficient potential.

[0070] Formula 2 is: muSquare = muEst 2 -muY 2 , muEst is the current estimated friction coefficient, muY is the lateral friction coefficient, and muSquare is the residual friction coefficient.

[0071] The preset relationship between the remaining friction coefficient and the potential longitudinal friction coefficient in this embodiment is shown in FIG2. After obtaining the remaining friction coefficient, the current potential longitudinal friction coefficient is obtained according to the linear relationship graph in FIG2.

[0072] The lateral friction coefficient and longitudinal friction coefficient are determined according to the tire stress and tire model. In the embodiments of this application, the lateral friction coefficient and longitudinal friction coefficient are known quantities.

[0073] For the calculation of the current estimated friction coefficient muEst, the embodiments of this application first calculate the intermediate variable using Formula 3, and then obtain the current estimated friction coefficient through the preset relationship between the intermediate variable and the estimated friction coefficient;

[0074] Formula 3 is: S = (0.2a) x ) 2 +(0.2a y ) 2 a x For longitudinal acceleration, a y Let S be the lateral acceleration, and S be an intermediate variable.

[0075] The preset relationship between the intermediate variable and the estimated friction coefficient in this embodiment is shown in FIG3. After obtaining the intermediate variable, the current estimated friction coefficient is obtained according to the linear relationship graph in FIG3.

[0076] In step S300, it is also necessary to detect the stability of the wheels on each axle. When the wheel speed difference between the left and right wheels is greater than a set threshold, it is determined that there is single-wheel stability on that axle. The set threshold is determined according to different vehicle models. Only when the maximum braking force difference is greater than the third preset threshold and the vehicle speed is less than the fourth preset threshold, and there is single-wheel stability on each axle, is it determined that the current vehicle is in a driving condition.

[0077] In step S500, the longitudinal friction coefficient needs to be greater than the current longitudinal friction coefficient. At this time, the difference between the longitudinal friction coefficient and the current longitudinal friction coefficient potential is obtained by subtracting the current longitudinal friction coefficient potential from the longitudinal friction coefficient.

[0078] In step S600, the current longitudinal friction coefficient needs to be greater than the longitudinal friction coefficient. The difference between the current longitudinal friction coefficient potential and the longitudinal friction coefficient potential is obtained by subtracting the longitudinal friction coefficient potential from the current longitudinal friction coefficient potential.

[0079] As shown in Figure 4, the working conditions that need to be identified in the traction control system of this application mainly include curve working conditions, split working conditions, slope working conditions, and friction coefficient utilization status.

[0080] As shown in Figure 5, the specific identification process steps for the curve condition are as follows: the wheel speeds of the left and right wheels of the drive shaft are subtracted and the absolute value is taken to obtain the wheel speed difference; when the wheel speed difference is greater than the first preset threshold and the vehicle speed is greater than the second preset threshold, the current vehicle is considered to be in a curve condition, where the first and second preset thresholds are determined according to different vehicle models.

[0081] When identifying cornering conditions, a lower speed limit is set. Cornering is only detected when the vehicle speed exceeds a certain value, ensuring functional stability and preventing false identification of conditions. If the wheel speed difference is large enough but the vehicle speed is too low, it is not considered a cornering condition because no additional control is needed when cornering at low speeds; normal default control is sufficient. Only when the speed is high enough is it considered a cornering condition.

[0082] As shown in Figure 6, the specific identification process for the split-wheel driving condition is as follows: The braking forces of the left and right wheels of each axle are subtracted, their absolute values ​​are compared, and the maximum value is taken to obtain the maximum braking force difference. When the maximum braking force difference is greater than a third preset threshold, the vehicle speed is less than a fourth preset threshold, and each axle exhibits single-wheel stability, the vehicle is considered to be in a split-wheel driving condition. The third and fourth preset thresholds vary depending on the vehicle model.

[0083] When the braking force difference is large enough, but the vehicle speed is too high, it is not considered a split-drive condition. The purpose of identifying split-drive conditions is to provide the vehicle with a larger amount of slippage to ensure sufficient power. When the vehicle speed is high enough, no additional slippage is needed, and no additional control is required for split-drive conditions.

[0084] Figure 7 shows the specific steps for identifying slope conditions: The driving gradient is calculated using Formula 1; when the driving gradient is greater than the fifth preset threshold and the vehicle speed is less than the sixth preset threshold, the vehicle is considered to be in a slope condition. The fifth and sixth preset thresholds are determined according to different vehicle models.

[0085] When the slope calculated using acceleration meets the conditions, but the vehicle speed is too high, it is not considered a slope condition. In the traction control system, the slope condition is combined with the split-drive condition to form an uphill split-drive condition. Similarly, the uphill split-drive condition is designed to provide the vehicle with greater slippage to ensure sufficient power. When the vehicle speed is high enough, no additional slippage is needed, and therefore no additional control for the split-drive condition is required. In this application's embodiment, when identifying split-drive and slope conditions, an upper limit is set on the vehicle speed. When the vehicle speed exceeds a certain value, the condition is no longer activated, ensuring the rationality of condition identification. Because the split-drive condition provides more power, unnecessary energy consumption can be avoided.

[0086] Figure 8 shows the specific steps for identifying the utilization status of the friction coefficient: Calculate the remaining friction based on the current estimated friction coefficient and lateral friction coefficient; Calculate the current longitudinal friction coefficient potential based on the remaining friction coefficient;

[0087] The system determines whether the current longitudinal friction coefficient potential is less than the seventh preset threshold. If so, it indicates that the current longitudinal friction coefficient potential is too low, leading to excessive utilization of the lateral friction coefficient and consequently, excessive utilization of the longitudinal friction coefficient. Next, it determines whether the difference between the current longitudinal friction coefficient and the current longitudinal friction coefficient potential is greater than the eighth preset threshold. If so, it indicates excessive utilization of the longitudinal friction coefficient. If both conditions are met, the longitudinal friction coefficient is considered to be overutilized, reducing the vehicle's resistance to sideslip. The seventh and eighth preset thresholds vary depending on the vehicle model.

[0088] The system determines whether the difference between the current potential longitudinal friction coefficient and the actual longitudinal friction coefficient is greater than a ninth preset threshold. If so, the longitudinal friction coefficient is considered underutilized. Next, it determines whether the lateral friction coefficient is greater than a tenth preset threshold. If so, the lateral friction coefficient is considered overutilized. If both conditions are met, the longitudinal friction coefficient is considered underutilized, resulting in insufficient vehicle traction and power. The ninth and tenth preset thresholds vary depending on the vehicle model.

[0089] When assessing the utilization of the friction coefficient, excessive utilization of the longitudinal friction coefficient reduces the vehicle's ability to resist sideslip; excessive utilization of the lateral friction coefficient can lead to insufficient traction, necessitating timely adjustments to the vehicle's condition. Understandably, when a vehicle travels at high speeds on asphalt roads, excessive utilization of the longitudinal friction coefficient can easily lead to lateral instability and reduced resistance to sideslip. Conversely, during sharp turns, insufficient utilization of the longitudinal friction coefficient can result in insufficient traction.

[0090] This application also provides a vehicle operating condition recognition system for traction control, including: a calculation and acquisition module and a judgment module.

[0091] The calculation and acquisition module in this embodiment of the application is used to acquire vehicle speed, wheel speed difference between the left and right wheels of the drive axle, maximum braking force difference between the left and right wheels of each axle, driving slope, current potential longitudinal friction coefficient, longitudinal friction coefficient, and lateral friction coefficient.

[0092] The judgment module is used to determine that the vehicle is currently in a curve condition when the wheel speed difference is greater than a first preset threshold and the vehicle speed is greater than a second preset threshold; to determine that the vehicle is currently in a driving condition when the maximum braking force difference is greater than a third preset threshold and the vehicle speed is less than a fourth preset threshold; to determine that the vehicle is currently in a slope condition when the driving gradient is greater than a fifth preset threshold and the vehicle speed is less than a sixth preset threshold; to determine that the longitudinal friction coefficient is overutilized when the current longitudinal friction coefficient potential is less than a seventh preset threshold and the difference between the longitudinal friction coefficient and the current longitudinal friction coefficient potential is greater than an eighth preset threshold; and to determine that the longitudinal friction coefficient is underutilized when the difference between the longitudinal friction coefficient and the current longitudinal friction coefficient potential is greater than a ninth preset threshold and the lateral friction coefficient is greater than a tenth preset threshold.

[0093] This application also provides a vehicle including the aforementioned traction control vehicle condition recognition system. It is understood that the content of the above-mentioned traction control vehicle condition recognition method and system embodiments is applicable to this vehicle embodiment. The specific functions implemented in this vehicle embodiment are the same as those in the traction control vehicle condition recognition method and system embodiments, and the beneficial effects achieved are also the same as those achieved in the above-mentioned traction control vehicle condition recognition method and system embodiments.

[0094] Specifically, the vehicle can be a private car, such as a sedan, SUV, MPV, or pickup truck. The vehicle can also be a commercial vehicle, such as a van, bus, small truck, or large semi-trailer. The vehicle can be a gasoline-powered vehicle or a new energy vehicle. When the vehicle is a new energy vehicle, it can be a hybrid vehicle or a pure electric vehicle.

[0095] According to an embodiment of this application, a computer-readable storage medium stores a computer program thereon, which, when executed by a processor, implements the above-described vehicle condition identification method for traction control.

[0096] The computer-readable storage medium of this application embodiment can be any combination of one or more computer-readable media. The computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium can be, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of computer-readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable computer disk, a 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 thereof. In this application embodiment, the computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0097] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, capable of sending, propagating, or transmitting programs for use by or in connection with an instruction execution system, apparatus, or device.

[0098] Program code contained on a computer-readable medium may be transmitted using any suitable medium, including but not limited to: wireless, wire, optical fiber, RF, etc., or any suitable combination thereof.

[0099] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0100] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0101] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application.

Claims

1. A vehicle operating condition identification method for traction control, comprising: Obtain vehicle speed, wheel speed difference between the left and right wheels of the drive axle, maximum braking force difference between the left and right wheels of each axle, driving gradient, current potential longitudinal friction coefficient, longitudinal friction coefficient, and lateral friction coefficient; When the wheel speed difference is greater than a first preset threshold and the vehicle speed is greater than a second preset threshold, it is determined that the current vehicle is in a curve condition. When the maximum braking force difference is greater than the third preset threshold and the vehicle speed is less than the fourth preset threshold, it is determined that the current vehicle is in a two-way working condition. When the driving gradient is greater than the fifth preset threshold and the vehicle speed is less than the sixth preset threshold, it is determined that the current vehicle is in a slope condition. When the potential of the current longitudinal friction coefficient is less than the seventh preset threshold and the difference between the longitudinal friction coefficient and the potential of the current longitudinal friction coefficient is greater than the eighth preset threshold, it is determined that the longitudinal friction coefficient is overutilized. If the difference between the longitudinal friction coefficient and the potential of the current longitudinal friction coefficient is greater than a ninth preset threshold and the lateral friction coefficient is greater than a tenth preset threshold, then it is determined that the longitudinal friction coefficient is underutilized.

2. The vehicle operating condition identification method for traction control according to claim 1, wherein: The acquisition of vehicle speed, wheel speed difference between the left and right wheels of the drive axle, maximum braking force difference between the left and right wheels of each axle, driving gradient, current potential longitudinal friction coefficient, longitudinal friction coefficient, and lateral friction coefficient includes: The wheel speeds of the left and right wheels of the drive shaft are detected, the difference is calculated, and the absolute value is taken to obtain the wheel speed difference.

3. The vehicle operating condition identification method for traction control according to claim 1, wherein: The acquisition of vehicle speed, wheel speed difference between the left and right wheels of the drive axle, maximum braking force difference between the left and right wheels of each axle, driving gradient, current potential longitudinal friction coefficient, longitudinal friction coefficient, and lateral friction coefficient includes: The braking force of the left and right wheels of each axle is detected, and the difference between the braking force of the left and right wheels of each axle is calculated. The absolute values ​​are then compared to obtain the maximum braking force difference.

4. The vehicle operating condition identification method for traction control according to claim 1, wherein: The acquisition of vehicle speed, wheel speed difference between the left and right wheels of the drive axle, maximum braking force difference between the left and right wheels of each axle, driving gradient, current potential longitudinal friction coefficient, longitudinal friction coefficient, and lateral friction coefficient includes: The driving gradient is calculated using Formula 1. Formula 1 is: i = (ax - a) / g, where ax is the value of the inertial acceleration sensor, a is the actual acceleration of the vehicle, g is the acceleration due to gravity, and i is the driving slope.

5. The vehicle operating condition identification method for traction control according to claim 1, wherein: The acquisition of vehicle speed, wheel speed difference between the left and right wheels of the drive axle, maximum braking force difference between the left and right wheels of each axle, driving gradient, current potential longitudinal friction coefficient, longitudinal friction coefficient, and lateral friction coefficient includes: The residual friction coefficient is calculated using Formula 2. The current longitudinal friction coefficient potential is obtained by a preset relationship between the remaining friction coefficient and the longitudinal friction coefficient potential. Formula 2 is: muSquare = muEst 2 -muY 2 , muEst is the current estimated friction coefficient, muY is the lateral friction coefficient, and muSquare is the residual friction coefficient.

6. The vehicle operating condition identification method for traction control according to claim 5, wherein: The residual friction coefficient calculated using Formula 2 includes: The intermediate variables are calculated using Formula 3; The current estimated friction coefficient is obtained through a preset relationship between intermediate variables and the estimated friction coefficient; Formula 3 is: S = (0.2a) x ) 2 +(0.2a y ) 2 a x For longitudinal acceleration, a y Let S be the lateral acceleration, and S be an intermediate variable.

7. The vehicle operating condition identification method for traction control according to claim 1, wherein: The step of determining that the longitudinal friction coefficient utilization is too high when the current potential longitudinal friction coefficient is less than a seventh preset threshold and the difference between the longitudinal friction coefficient and the current potential longitudinal friction coefficient is greater than an eighth preset threshold includes: The difference between the longitudinal friction coefficient and the potential of the current longitudinal friction coefficient is obtained by subtracting the potential of the current longitudinal friction coefficient from the longitudinal friction coefficient.

8. The vehicle operating condition identification method for traction control according to claim 1, wherein: The step of determining that the longitudinal friction coefficient is underutilized when the difference between the longitudinal friction coefficient and the current potential longitudinal friction coefficient is greater than a ninth preset threshold and the lateral friction coefficient is greater than a tenth preset threshold includes: The difference between the potential longitudinal friction coefficient and the potential longitudinal friction coefficient is obtained by subtracting the potential longitudinal friction coefficient from the potential potential.

9. The vehicle operating condition identification method for traction control according to claim 1, wherein: The step of determining that the current vehicle is in a driving condition when the maximum braking force difference is greater than a third preset threshold and the vehicle speed is less than a fourth preset threshold further includes: Check the stability of the wheels on each axle; When the maximum braking force difference is greater than the third preset threshold, the vehicle speed is less than the fourth preset threshold, and each axle has single-wheel stability, it is determined that the current vehicle is in a two-wheel driving condition.

10. A vehicle operating condition recognition system for traction control, comprising: The calculation and acquisition module is used to obtain vehicle speed, wheel speed difference between the left and right wheels of the drive axle, maximum braking force difference between the left and right wheels of each axle, driving gradient, current potential longitudinal friction coefficient, longitudinal friction coefficient, and lateral friction coefficient. The judgment module is used to determine that the current vehicle is in a curve condition when the wheel speed difference is greater than a first preset threshold and the vehicle speed is greater than a second preset threshold. When the maximum braking force difference is greater than the third preset threshold and the vehicle speed is less than the fourth preset threshold, it is determined that the current vehicle is in a two-way working condition. When the driving gradient is greater than the fifth preset threshold and the vehicle speed is less than the sixth preset threshold, it is determined that the current vehicle is in a slope condition; when the current longitudinal friction coefficient potential is less than the seventh preset threshold and the difference between the longitudinal friction coefficient and the current longitudinal friction coefficient potential is greater than the eighth preset threshold, it is determined that the longitudinal friction coefficient is overutilized. If the difference between the longitudinal friction coefficient and the potential of the current longitudinal friction coefficient is greater than a ninth preset threshold and the lateral friction coefficient is greater than a tenth preset threshold, then it is determined that the longitudinal friction coefficient is underutilized.

11. A vehicle comprising a vehicle condition recognition system for traction control as described in claim 10.

12. A computer-readable storage medium storing computer-executable instructions for causing a computer to perform the vehicle condition identification method for traction control as described in any one of claims 1 to 9.

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