Road surface adhesion recognition method and device, storage medium and product

Abstract

The application provides a road adhesion recognition method and device, a storage medium and a product. The method obtains state information of a vehicle during driving, determines a vehicle working state, wherein the vehicle working state includes multiple different states, obtains corresponding recognition parameters according to the vehicle working state, matches the recognition parameters corresponding to the vehicle working state and corresponding parameter thresholds, obtains a road adhesion degree level under the vehicle working state, and determines a road adhesion degree parameter according to the road adhesion degree level and the vehicle working state. Therefore, the application determines corresponding adhesion degree parameters through different vehicle working states, thereby avoiding the defect that a dynamic equation cannot obtain an accurate road adhesion coefficient when the vehicle is driving stably, and improving the accuracy of obtaining the road adhesion coefficient.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle control, and in particular to a road adhesion identification method and device, a storage medium and a product. BACKGROUND

[0002] The road adhesion coefficient refers to the friction coefficient between the tire of a vehicle and the ground. The road adhesion coefficient has an important influence on the driving and braking control of the vehicle.

[0003] The existing scheme for obtaining the road adhesion coefficient is usually based on a pre-established dynamic model to determine the corresponding road adhesion coefficient. However, the scheme based on the dynamic model cannot accurately obtain the road adhesion coefficient when the vehicle is in a uniform speed state. SUMMARY

[0004] The present application provides a road adhesion identification method and device, a storage medium and a product to solve the problem that the existing scheme cannot accurately obtain the road adhesion coefficient when the vehicle is in a uniform speed state.

[0005] In a first aspect, the present application provides a road adhesion identification method, comprising:

[0006] According to the state information of the vehicle in the driving process, the working state of the vehicle is determined, and the working state of the vehicle is one of the following: driving state, braking state, driving state, anti-lock braking system (ABS) state, acceleration slip regulation (ASR) state, and unknown state.

[0007] According to the working state of the vehicle, the corresponding identification parameter is obtained. The identification parameter of the driving state includes the fitting straight line slope between the total slip rate of each wheel on the vehicle and the longitudinal acceleration. The identification parameter of the braking state includes the ratio between the longitudinal acceleration and the total slip rate. The identification parameter of the driving state includes the longitudinal acceleration and the drive shaft slip rate. The identification parameters of the ABS state and the ASR state are both the longitudinal acceleration. The drive shaft slip rate is the average value of the slip rate of the wheels on the drive shaft. The slip rate of the wheel is the proportion of the difference between the wheel speed and the vehicle speed in the vehicle speed.

[0008] The identification parameter corresponding to the working state of the vehicle and the corresponding parameter threshold are matched to obtain the road adhesion level of the working state of the vehicle.

[0009] According to the road adhesion level and the working state of the vehicle, the road adhesion level parameter is determined.

[0010] In a possible implementation, the driving state satisfies the following conditions: an absolute value of the longitudinal acceleration is less than a first acceleration threshold value, an absolute value of a total slip ratio of each wheel on the vehicle is less than a first total slip ratio threshold value, an accelerator pedal opening degree is less than a first accelerator opening degree threshold value, a brake pedal opening degree is less than a first brake opening degree threshold value, a vehicle speed is greater than or equal to a first vehicle speed threshold value, an absolute value of a drive shaft slip ratio is less than a first drive slip ratio threshold value, and an absolute value of a steering wheel rotation angle is less than a first rotation angle threshold value;

[0011] The braking state satisfies the following conditions: the brake pedal opening degree is greater than or equal to a second brake opening degree threshold value, the vehicle speed is greater than or equal to a second vehicle speed threshold value, ABS is not activated, the absolute value of the longitudinal acceleration is less than a second acceleration threshold value, and the absolute value of the total slip ratio is less than a second total slip ratio threshold value;

[0012] The driving state satisfies the following conditions: ASR is not activated, no gear shifting is performed, the drive shaft slip ratio is greater than or equal to a third drive slip ratio threshold value, and the longitudinal acceleration is greater than or equal to a third acceleration threshold value;

[0013] The ABS state satisfies the following conditions: ABS is activated, the ABS activation signal indicates an activated state, and ABS working states of at least two wheels are in a pressure reduction state;

[0014] The ASR state satisfies the following condition: an ASR activation signal indicates an activated state.

[0015] In a possible implementation, the matching of the identification parameter corresponding to the vehicle working state and the corresponding parameter threshold value obtains a road adhesion degree level in the vehicle working state, including:

[0016] One or more value ranges are constructed according to the parameter threshold value corresponding to each vehicle working state, and different value ranges correspond to different levels;

[0017] The value range in which the identification parameter is located is determined as a target value range, and a level corresponding to the target value range is taken as the road adhesion degree level.

[0018] In a possible implementation, in the driving state, the road adhesion degree level is positively correlated with a fitting straight line slope, and the fitting straight line slope is fitted with the total slip ratio as the horizontal axis and the longitudinal acceleration as the vertical axis;

[0019] In the braking state, the road adhesion degree level is positively correlated with the ratio;

[0020] In the driving state, the road adhesion level is positively correlated with the longitudinal acceleration and positively correlated with the drive shaft slip rate;

[0021] In the ABS state, the road adhesion level is positively correlated with the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in a time period, the maximum longitudinal acceleration and the minimum longitudinal acceleration are equal in absolute value but opposite in sign;

[0022] In the ASR state, the road adhesion level is positively correlated with the maximum longitudinal acceleration in a time period;

[0023] In the unknown state, the last identified road adhesion level is the road adhesion level identified this time.

[0024] In a possible implementation, when the slope of the fitted straight line is greater than or equal to a first slope threshold, the road adhesion level is a first level, when the slope of the fitted straight line is less than the first slope threshold and greater than or equal to a second slope threshold, the road adhesion level is a second level, and when the slope of the fitted straight line is less than the second slope threshold, the road adhesion level is a third level;

[0025] In the braking state, when a plurality of consecutive ratios are greater than or equal to a first ratio threshold, the road adhesion level is a first level, when a plurality of consecutive ratios are less than the first ratio threshold and greater than or equal to a second ratio threshold, the road adhesion level is a second level, and when the ratio is less than the second ratio threshold, the road adhesion level is a third level;

[0026] In the driving state, when the longitudinal acceleration is greater than or equal to a fourth acceleration threshold for a plurality of times, the road adhesion level is a first level, when the longitudinal acceleration is less than the fourth acceleration threshold but greater than or equal to a fifth acceleration threshold for a plurality of times, and the drive shaft slip rate is greater than or equal to a fourth drive slip rate threshold for a plurality of times, the road adhesion level is a second level, otherwise, the road adhesion level is a third level;

[0027] In the ABS state, when the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in a plurality of consecutive time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion level is a first level, when the maximum longitudinal deceleration in a plurality of consecutive time periods is less than the first maximum acceleration threshold and greater than or equal to a second maximum acceleration threshold, the road adhesion level is a second level, and when the maximum longitudinal deceleration in a plurality of consecutive time periods is less than the second maximum acceleration threshold, the road adhesion level is the third level;

[0028] In the ASR state, when the maximum longitudinal acceleration of the continuous multiple time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion degree level is a first level, when the maximum longitudinal acceleration of the continuous multiple time periods is less than the first maximum acceleration threshold and greater than or equal to a second maximum acceleration threshold, the road adhesion degree level is a second level, and when the maximum longitudinal acceleration of the continuous multiple time periods is less than the second maximum acceleration threshold, the road adhesion degree level is the third level.

[0029] In a possible implementation, when the vehicle working state is a target working mode, a corresponding road adhesion degree parameter is determined according to the road adhesion degree level, the road adhesion degree parameter is positively correlated with the road adhesion degree level, and the target working mode includes the driving state, the driving state, the braking state and the unknown state.

[0030] When the vehicle working state is a mode other than the target working mode, the longitudinal acceleration is determined as the road adhesion degree parameter.

[0031] In a second aspect, the embodiments of the present application provide a road adhesion recognition device, comprising:

[0032] The acquisition module is configured to determine a vehicle working state according to state information of the vehicle in a driving process, and the vehicle working state is one of the following: a driving state, a braking state, a driving state, an anti-lock braking system (ABS) state, an acceleration slip regulation (ASR) state, and an unknown state.

[0033] The first processing module is configured to obtain a corresponding recognition parameter according to the vehicle working state, the recognition parameter of the driving state includes a fitting straight line slope between a total slip rate of each wheel on the vehicle and a longitudinal acceleration, the recognition parameter of the braking state includes a ratio between the longitudinal acceleration and the total slip rate, the recognition parameter of the driving state includes the longitudinal acceleration and a drive shaft slip rate, the recognition parameter of the ABS state and the ASR state is the longitudinal acceleration, the drive shaft slip rate is an average value of slip rates of wheels on the drive shaft, and the slip rate of the wheel is a proportion of a difference between a wheel speed and a vehicle speed in the vehicle speed.

[0034] The second processing module is configured to match the recognition parameter corresponding to the vehicle working state and a corresponding parameter threshold to obtain a road adhesion degree level in the vehicle working state.

[0035] The control module is configured to determine a road adhesion degree parameter according to the road adhesion degree level and the vehicle working state.

[0036] In a possible implementation, the obtaining module is specifically configured to match the identification parameter corresponding to the vehicle working state with the parameter threshold value corresponding to the vehicle working state, to obtain the road adhesion degree level in the vehicle working state, including:

[0037] the brake state satisfies the following conditions: the brake pedal opening degree is greater than or equal to a second brake opening degree threshold value, the vehicle speed is greater than or equal to a second vehicle speed threshold value, ABS is not activated, the absolute value of the longitudinal acceleration is less than a second acceleration threshold value, and the absolute value of the total slip rate is less than a second total slip rate threshold value;

[0038] the drive state satisfies the following conditions: ASR is not activated, gear shifting is not performed, the drive shaft slip rate is greater than or equal to a third drive slip rate threshold value, and the longitudinal acceleration is greater than or equal to a third acceleration threshold value;

[0039] the ABS state satisfies the following conditions: ABS is activated, the ABS activation signal indicates an activated state, and the ABS working state of at least two wheels is a pressure reduction state;

[0040] the ASR state satisfies the following conditions: an ASR activation signal indicates an activated state.

[0041] In a possible implementation, the obtaining module is specifically configured to match the identification parameter corresponding to the vehicle working state with the parameter threshold value corresponding to the vehicle working state, to obtain the road adhesion degree level in the vehicle working state, including:

[0042] one or more value ranges are constructed according to the parameter threshold value corresponding to each vehicle working state, and different value ranges correspond to different levels;

[0043] the value range in which the identification parameter is located is determined as a target value range, and the level corresponding to the target value range is taken as the road adhesion degree level.

[0044] In a possible implementation, the first processing module is specifically configured to, in the driving state, the road adhesion degree level is positively correlated with the slope of the fitting straight line, the slope of the fitting straight line is obtained by fitting the total slip rate as the horizontal axis and the longitudinal acceleration as the vertical axis;

[0045] in the brake state, the road adhesion degree level is positively correlated with the ratio;

[0046] in the driving state, the road adhesion level is positively correlated with the longitudinal acceleration and positively correlated with the drive shaft slip rate;

[0047] in the ABS state, the road adhesion level is positively correlated with the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in a time period, the maximum longitudinal acceleration and the minimum longitudinal acceleration have equal absolute values but opposite signs;

[0048] in the ASR state, the road adhesion level is positively correlated with the maximum longitudinal acceleration in a time period;

[0049] in the unknown state, the last identified road adhesion level is the road adhesion level identified this time.

[0050] in a possible implementation, the first processing module is specifically configured to: when the slope of the fitting straight line is greater than or equal to a first slope threshold, the road adhesion level is a first level; when the slope of the fitting straight line is less than the first slope threshold and greater than or equal to a second slope threshold, the road adhesion level is a second level; and when the slope of the fitting straight line is less than the second slope threshold, the road adhesion level is a third level;

[0051] in the braking state, when a plurality of consecutive ratios are greater than or equal to a first ratio threshold, the road adhesion level is a first level; when the plurality of consecutive ratios are less than the first ratio threshold and greater than or equal to a second ratio threshold, the road adhesion level is a second level; and when the ratio is less than the second ratio threshold, the road adhesion level is a third level;

[0052] in the driving state, when the longitudinal acceleration is greater than or equal to a fourth acceleration threshold for a plurality of times, the road adhesion level is a first level; when the longitudinal acceleration is less than the fourth acceleration threshold but greater than or equal to a fifth acceleration threshold for a plurality of times, and the drive shaft slip rate is greater than or equal to a fourth drive slip rate threshold for a plurality of times, the road adhesion level is a second level; otherwise, the road adhesion level is a third level;

[0053] in the ABS state, when the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in a plurality of consecutive time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion level is a first level; when the maximum longitudinal deceleration in the plurality of consecutive time periods is less than the first maximum acceleration threshold and greater than or equal to a second maximum acceleration threshold, the road adhesion level is a second level; and when the maximum longitudinal deceleration in the plurality of consecutive time periods is less than the second maximum acceleration threshold, the road adhesion level is the third level.

[0054] In the ASR state, when the maximum longitudinal acceleration of the continuous multiple time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion degree level is a first level, when the maximum longitudinal acceleration of the continuous multiple time periods is less than the first maximum acceleration threshold and greater than or equal to a second maximum acceleration threshold, the road adhesion degree level is a second level, and when the maximum longitudinal acceleration of the continuous multiple time periods is less than the second maximum acceleration threshold, the road adhesion degree level is the third level.

[0055] In a possible implementation, the control module is specifically configured to determine a corresponding road adhesion degree parameter according to the road adhesion degree level when the vehicle working state is a target working mode, the road adhesion degree parameter is positively correlated with the road adhesion degree level, and the target working mode includes the driving state, the driving state, the braking state and the unknown state.

[0056] When the vehicle working state is a mode other than the target working mode, the longitudinal acceleration is determined as the road adhesion degree parameter.

[0057] In a third aspect, an embodiment of the present application provides an electronic device, comprising: a processor, and a memory connected with the processor in communication;

[0058] The memory stores computer execution instructions;

[0059] The processor executes the computer execution instructions stored in the memory to implement the method as described above.

[0060] In a fourth aspect, an embodiment of the present application provides a computer readable storage medium, and the computer readable storage medium stores computer execution instructions, and the computer execution instructions are executed by a processor to implement the method as described above.

[0061] In a fifth aspect, an embodiment of the present application provides a computer program product, and the computer program product comprises a computer program, and the computer program is executed by a processor to implement the method as described above.

[0062] The road surface adhesion recognition method, device, storage medium and product provided by the embodiment of the present application, by acquiring the state information of the vehicle in the driving process, determining the working state of the vehicle, wherein the working state of the vehicle includes a plurality of different states, acquiring the corresponding recognition parameter according to the working state of the vehicle, matching the recognition parameter corresponding to the working state of the vehicle and the corresponding parameter threshold, obtaining the road surface adhesion degree level under the working state of the vehicle, and determining the road surface adhesion degree parameter according to the road surface adhesion degree level and the working state of the vehicle. Therefore, the present application determines the corresponding adhesion degree parameter through different working states of the vehicle, thereby avoiding the defect that the kinetic equation cannot obtain an accurate road surface adhesion coefficient when the vehicle is driving smoothly, and improving the accuracy of obtaining the road surface adhesion coefficient. BRIEF DESCRIPTION OF DRAWINGS

[0063] The accompanying drawings, which are incorporated herein and constitute part of the specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0064] Figure 1 The basic framework schematic diagram provided by the present application is shown in the following figure;

[0065] Figure 2 The flowchart of the road surface adhesion recognition method provided by the present application is shown in the following figure Figure 1 ;

[0066] Figure 3 The flowchart of the road surface adhesion recognition method provided by the present application is shown in the following figure Figure 2 ;

[0067] Figure 4 The structure schematic diagram of the road surface adhesion recognition device provided by the present application is shown in the following figure;

[0068] Figure 5 The structure schematic diagram of the electronic device provided by the present application is shown in the following figure.

[0069] Through the above-mentioned drawings, the specific embodiments of the present application have been shown, and more detailed descriptions will be given in the following. These drawings and textual descriptions are not intended to limit the scope of the concept of the present application by any means, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0070] The exemplary embodiments will be described in detail herein with reference to the accompanying drawings. Unless otherwise indicated, the same numbers on different drawings represent the same or similar elements. The following detailed description does not limit the present application to particular embodiments described, but the application extends to other embodiments as noted.

[0071] It should be noted that the user information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in one or more embodiments of the present specification are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of related data need to comply with relevant laws, regulations and standards, and provide corresponding operation portal for user to choose authorization or rejection.

[0072] It should be noted that in the embodiments of the present application, some industry existing solutions of software, components, models, etc. may be mentioned, which should be considered as exemplary, and the purpose is only to illustrate the feasibility in the implementation of the technical solutions of the present application, but it does not mean that the applicant has or will necessarily use the solution.

[0073] The road adhesion coefficient is an important parameter to measure the friction between the tire and the road, which directly affects the driving safety, stability and handling performance of the vehicle. The road adhesion coefficient is affected by many factors, including road material, dry or wet condition, tire structure, tread pattern and vehicle speed.

[0074] The existing scheme for obtaining the road adhesion coefficient includes an estimation method based on an empirical model and a real-time estimation method based on an observation model. For the estimation method based on the empirical model, the main factor parameters affecting the adhesion coefficient are measured by various vehicle sensors, and the road adhesion coefficient is estimated by combining the established tire mechanics model with the empirical formula; for the real-time estimation method based on the observation model, the sensor data obtained is processed by combining various sensor data such as vehicle-mounted camera and high-precision map sensing data, and by filtering algorithm, the motion state of the wheel is determined according to the processed sensor data, and the road adhesion coefficient is estimated in real time according to the motion state.

[0075] It is found that the working process of the above-mentioned existing scheme is that when the tire mechanics model is established, only when the wheel appears obvious slip such as vehicle rapid acceleration or deceleration, the accurate tire mechanics model can be established according to the vehicle slip data, so as to obtain the road adhesion coefficient based on the established tire mechanics model, at this time the observability of the road adhesion coefficient is high; when the vehicle is running smoothly such as uniform speed or slow acceleration and deceleration, there is no obvious vehicle slip data, and the accurate and suitable tire mechanics model cannot be established, at this time the observability of the road adhesion coefficient is poor, and the road adhesion coefficient cannot be accurately obtained.

[0076] Therefore, the application provides a road adhesion recognition method, which acquires state information of a vehicle in a driving process, determines a vehicle working state, wherein the vehicle working state includes a plurality of different states, acquires corresponding recognition parameters according to the vehicle working state, matches the recognition parameters corresponding to the vehicle working state and corresponding parameter thresholds, obtains a road adhesion degree level in the vehicle working state, and determines a road adhesion degree parameter according to the road adhesion degree level and the vehicle working state. Therefore, the application determines corresponding adhesion degree parameters through different vehicle working states, thereby avoiding the defect that a dynamic equation cannot acquire an accurate road adhesion coefficient when the vehicle is driving stably, and improving the accuracy of acquiring the road adhesion coefficient.

[0077] The technical solutions of the application and how the technical solutions solve the above technical problems will be described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes can not be described again in some embodiments. The embodiments of the application will be described below with reference to the drawings.

[0078] Figure 1 The basic framework provided by the application is shown in the following schematic diagram, Figure 2 The flowchart of the road adhesion recognition method provided by the application is shown in the following schematic diagram Figure 1 , combined with Figure 2 and Figure 3 , the method comprises:

[0079] S101, determining a vehicle working state according to state information of the vehicle in a driving process, wherein the vehicle working state is one of the following: a driving state, a braking state, a driving state, an ABS (Anti-lock Braking System) state, an ASR (Acceleration Slip Regulation) state, and an unknown state.

[0080] Specifically, when the vehicle is driving normally, the state information of the vehicle at this time is acquired through various vehicle-mounted sensors, wherein the vehicle state information includes wheel speeds of various wheels, longitudinal accelerations, total slip rates of various wheels, accelerator pedal opening degrees, brake pedal opening degrees, vehicle speeds, drive shaft slip rates, steering wheel angles, ABS (Anti-lock Braking System) activation states, and ASR (Acceleration Slip Regulation) activation states. The unknown state is a state other than the driving state, the braking state, the driving state, the ABS state, and the ASR state.

[0081] Further, for the longitudinal acceleration, after the vehicle obtains the acceleration signal and the vehicle speed signal through a sensor such as an inertial measurement unit (IMU), the acceleration signal and the vehicle speed signal are filtered through a Kalman filtering algorithm to obtain the filtered longitudinal acceleration and the vehicle speed.

[0082] Further, according to the wheel speed of each wheel and the vehicle speed, the slip ratio of each wheel is calculated and obtained, the sum of the slip ratios of each wheel is obtained as the total slip ratio, and the average of the slip ratios of the two wheels of the rear axle is obtained as the drive axle slip ratio.

[0083] S102, according to the vehicle working state, the corresponding identification parameter is obtained, the identification parameter of the driving state includes: the fitting straight line slope between the total slip ratio of each wheel on the vehicle and the longitudinal acceleration, the identification parameter of the braking state includes: the ratio between the longitudinal acceleration and the total slip ratio, the identification parameter of the driving state includes: the longitudinal acceleration and the drive axle slip ratio, the identification parameter of the ABS state and the ASR state is the longitudinal acceleration, the drive axle slip ratio is the average of the slip ratios of the wheels on the drive axle, and the slip ratio of the wheel is the proportion of the difference between the wheel speed and the vehicle speed in the vehicle speed.

[0084] Specifically, after determining the corresponding vehicle working state according to the state information, in the obtained state information, the corresponding state information is obtained according to the vehicle working state, and the corresponding identification parameter is obtained according to the corresponding state information.

[0085] Further, for the identification parameter of the driving state, a plurality of total slip ratios and corresponding longitudinal accelerations within a preset driving time in the driving state are obtained, a plurality of total slip ratios and corresponding longitudinal accelerations are linearly fitted through the recursive least square method, and the slope of the fitting straight line is obtained as the identification parameter of the driving state.

[0086] Further, for the identification parameter of the braking state, a plurality of longitudinal accelerations and corresponding total slip ratios within a preset continuous braking time in the braking state are obtained, and the ratio of the plurality of longitudinal accelerations to the corresponding total slip ratios is recorded as the identification parameter of the braking state.

[0087] S103, the identification parameter corresponding to the vehicle working state and the corresponding parameter threshold are matched to obtain the road adhesion degree grade in the vehicle working state.

[0088] Specifically, after determining the vehicle working state and obtaining the identification parameter corresponding to the vehicle working state, the corresponding parameter threshold is obtained from the threshold database according to the vehicle working state. After obtaining the corresponding parameter threshold, the identification parameter corresponding to the vehicle working state is compared with the obtained parameter threshold, and the road adhesion degree level under the corresponding vehicle working state is determined according to the comparison result. Wherein, a plurality of different vehicle working states and corresponding parameter thresholds are pre-associated and stored in the threshold database.

[0089] S104, determining a road adhesion degree parameter according to the road adhesion degree level and the vehicle working state.

[0090] Specifically, after determining the road adhesion degree level according to the vehicle working state and the corresponding identification parameter, the corresponding adhesion data group is obtained from the road adhesion database according to the vehicle working state. In the adhesion data group, the road surface type is confirmed according to the road adhesion degree level, and the corresponding road adhesion degree parameter is obtained according to the road surface type. The obtained road surface type and road adhesion degree parameter are taken as output to be used for vehicle control unit to control the vehicle according to the road surface type and road adhesion degree parameter.

[0091] Wherein, a plurality of vehicle working states and corresponding adhesion data groups are pre-associated and stored in the road adhesion database, and a plurality of different road adhesion degree levels, road surface types and corresponding road adhesion degree parameters are pre-associated and stored in the adhesion data group.

[0092] The road adhesion recognition method provided by the embodiment of the application determines the vehicle working state by obtaining the state information of the vehicle in the driving process, wherein the vehicle working state includes a plurality of different states, obtains the corresponding identification parameter according to the vehicle working state, matches the identification parameter corresponding to the vehicle working state with the corresponding parameter threshold, obtains the road adhesion degree level under the vehicle working state, and determines the road adhesion degree parameter according to the road adhesion degree level and the vehicle working state. Therefore, the application determines the corresponding adhesion degree parameter through different vehicle working states, thereby avoiding the defect that the dynamic equation cannot obtain accurate road adhesion coefficient when the vehicle is driving smoothly, and improving the accuracy of obtaining the road adhesion coefficient.

[0093] Figure 2 The flowchart of the road adhesion recognition method provided by the application is shown Figure 3 As shown in Figure 1 the embodiment Figure 4 on the basis of the embodiment, the road adhesion recognition method is described in detail, which comprises:

[0094] S201, determining the vehicle working state according to the state information of the vehicle in the driving process.

[0095] Specifically, the vehicle state information is acquired by the vehicle-mounted sensors, and the working state of the vehicle at the moment is determined according to the state information. When the absolute value of the longitudinal acceleration in the state information is less than a first acceleration threshold, the absolute value of the total slip ratio is less than a first total slip ratio threshold, the accelerator pedal opening is less than a first accelerator opening threshold, the brake pedal opening is less than a first brake opening threshold, the vehicle speed is greater than or equal to a first vehicle speed threshold, the absolute value of the drive shaft slip ratio is less than a first drive slip ratio threshold, and the absolute value of the steering wheel angle is less than a first angle threshold, it is determined that the vehicle is in a driving state at the moment.

[0096] Further, when the brake pedal opening in the state information is greater than or equal to a second brake opening threshold, the vehicle speed is greater than or equal to a second vehicle speed threshold, the ABS activation state indicates that the ABS is not activated, the absolute value of the longitudinal acceleration is less than a second acceleration threshold, and the absolute value of the total slip ratio is less than a second total slip ratio threshold, it is determined that the vehicle is in a braking state at the moment.

[0097] Further, when the ASR activation state in the state information indicates that the ASR is not activated, there is no gear shifting, the drive shaft slip ratio is greater than or equal to a third drive slip ratio threshold, and the longitudinal acceleration is greater than or equal to a third acceleration threshold, it is determined that the vehicle is in a driving state at the moment.

[0098] Further, when the ABS activation state in the state information indicates that the ABS is activated, the ABS activation signal indicates that the ABS is in an activated state, and the ABS working state of at least two wheels is a pressure reduction state, it is determined that the vehicle is in an ABS state at the moment; when the ASR activation state in the state information indicates that the ASR is in an activated state, it is determined that the vehicle is in an ASR state at the moment.

[0099] Further, when the above conditions are not met, an unknown state is entered.

[0100] S202, one or more value ranges are constructed according to the parameter thresholds corresponding to each vehicle working state, and different value ranges correspond to different levels.

[0101] Specifically, after determining the working state of the vehicle at the moment according to the acquired state information, the corresponding state information is acquired from the acquired state information according to the vehicle working state, and the corresponding identification parameters are acquired according to the corresponding state information. According to the vehicle working state, the corresponding parameter thresholds are acquired in the threshold database. One or more value ranges are constructed according to the parameter thresholds.

[0102] Further, for the parameter threshold of the driving state such as the first slope threshold, a value range greater than or equal to the first slope threshold is determined as a first driving value range of the driving state, a value range less than the first slope threshold and greater than or equal to the second slope threshold is determined as a second driving value range of the driving state, and a value range less than the second slope threshold is determined as a third driving value range of the driving state.

[0103] Further, for the parameter threshold of the braking state such as the first ratio threshold, a value range greater than or equal to the first ratio threshold is determined as a first braking value range of the braking state, a value range less than the first ratio threshold and greater than or equal to the second ratio threshold is determined as a second braking value range of the braking state, and a value range less than the second ratio threshold is determined as a third braking value range of the braking state.

[0104] Further, for the parameter threshold of the driving state such as the first slope threshold, a value range greater than or equal to the first slope threshold is determined as a first driving value range of the driving state, a value range less than the first slope threshold and greater than or equal to the second slope threshold is determined as a second driving value range of the driving state, and a value range less than the second slope threshold is determined as a third driving value range of the driving state.

[0105] Further, for the parameter threshold of the ABS state such as the first maximum acceleration threshold and the second maximum acceleration threshold, a value range greater than the first maximum acceleration threshold is determined as a first anti-lock value range of the ABS state, a value range less than the first maximum acceleration threshold and greater than or equal to the second maximum acceleration threshold is determined as a second anti-lock value range of the ABS state, and a value range less than the second maximum acceleration threshold is determined as a third anti-lock value range of the ABS state.

[0106] Further, for the parameter threshold of the ASR state such as the first maximum acceleration threshold and the second maximum acceleration threshold, a value range greater than or equal to the first maximum acceleration threshold is determined as a first anti-slip value range of the ASR state, a value range less than the first maximum acceleration threshold and greater than or equal to the second maximum acceleration threshold is determined as a second anti-slip value range of the ASR state, and a value range less than the second maximum acceleration threshold is determined as a third anti-slip value range of the ASR state.

[0107] S203, determining the value range in which the identified parameter is located as a target value range.

[0108] Specifically, after determining the vehicle working state and obtaining the identification parameter corresponding to the vehicle working state, the identification parameter corresponding to the vehicle working state is detected to determine the value range in which the identification parameter falls, and the value range in which the identification parameter falls is taken as the target value range. The value range in which the identification parameter falls is determined as the target value range, and the level corresponding to the target value range is taken as the road surface adhesion degree level.

[0109] S204, when the slope of the fitting straight line is greater than or equal to a first slope threshold, the road surface adhesion degree level is a first level, when the slope of the fitting straight line is less than the first slope threshold and greater than or equal to a second slope threshold, the road surface adhesion degree level is a second level, and when the slope of the fitting straight line is less than the second slope threshold, the road surface adhesion degree level is a third level.

[0110] Specifically, when the vehicle working state is the driving state, the identification parameter corresponding to the driving state, i.e. the slope of the fitting straight line, is greater than or equal to the first slope threshold, the identification parameter of the driving state falls into the first driving value range, and at this time the first driving value range is taken as the target value range, and at this time the road surface adhesion degree level is the first level.

[0111] Further, when the identification parameter corresponding to the driving state, i.e. the slope of the fitting straight line, is less than the first slope threshold and greater than or equal to the second slope threshold, the identification parameter of the driving state falls into the second driving value range, at this time the second driving value range is taken as the target value range, and at this time the road surface adhesion degree level is the second level.

[0112] Further, when the identification parameter corresponding to the driving state, i.e. the slope of the fitting straight line, is less than the second slope threshold, the identification parameter of the driving state falls into the third driving value range, at this time the third driving value range is taken as the target value range, and at this time the road surface adhesion degree level is the third level.

[0113] Wherein, the first level is used to indicate the high road surface adhesion degree, the second level is used to indicate the medium-low road surface adhesion degree, and the third level is used to indicate the low road surface adhesion degree; in the driving state, the road surface adhesion degree level is positively correlated with the slope of the fitting straight line, and the slope of the fitting straight line is obtained by fitting the total slip rate as the horizontal axis and the longitudinal acceleration as the vertical axis.

[0114] S205, in the braking state, when the plurality of consecutive ratios are greater than or equal to a first ratio threshold, the road surface adhesion degree level is a first level, when the plurality of consecutive ratios are less than the first ratio threshold and greater than or equal to a second ratio threshold, the road surface adhesion degree level is a second level, and when the ratio is less than the second ratio threshold, the road surface adhesion degree level is a third level.

[0115] Specifically, when the vehicle working state is the braking state, if the ratio between the longitudinal acceleration and the corresponding total slip rate corresponding to the braking state is greater than or equal to the first ratio threshold value for three consecutive times within the preset braking time, the identification parameter of the braking state falls into the first braking value range, the first braking value range is taken as the target value range, and the road adhesion degree level is the first level.

[0116] Further, when the ratio is less than the first ratio threshold value and greater than or equal to the second ratio threshold value for three consecutive times, the identification parameter of the braking state falls into the second braking value range, the second braking value range is taken as the target value range, and the road adhesion degree level is the second level.

[0117] Further, when the ratio between the longitudinal acceleration and the corresponding total slip rate is less than the second ratio threshold value, the identification parameter of the braking state falls into the third braking value range, the third braking value range is taken as the target value range, and the road adhesion degree level is the third level. In the braking state, the road adhesion degree level is positively correlated with the ratio.

[0118] S206, in the driving state, when the longitudinal acceleration is greater than or equal to the fourth acceleration threshold value for multiple consecutive times, the road adhesion degree level is the first level, when the longitudinal acceleration is less than the fourth acceleration threshold value but greater than or equal to the fifth acceleration threshold value for multiple consecutive times, and the drive shaft slip rate is greater than or equal to the fourth drive slip rate threshold value for multiple consecutive times, the road adhesion degree level is the second level, otherwise, the road adhesion degree level is the third level.

[0119] Specifically, when the vehicle working state is the driving state, if the ratio between the longitudinal acceleration and the corresponding drive shaft slip rate corresponding to the driving state is greater than or equal to the fourth acceleration threshold value for three consecutive times within the preset driving time, the identification parameter of the driving state falls into the first driving value range, the first driving value range is taken as the target value range, and the road adhesion degree level is the first level.

[0120] Further, when the longitudinal acceleration is less than the fourth acceleration threshold value but greater than or equal to the fifth acceleration threshold value, and the drive shaft slip rate is greater than or equal to the fourth drive slip rate threshold value for three consecutive times, the identification parameter of the driving state falls into the second driving value range, the second driving value range is taken as the target value range, and the road adhesion degree level is the second level.

[0121] Further, when the identification parameter of the driving state does not fall into the first driving value range and the second driving value range, it is determined that the identification parameter of the driving state falls into the third driving value range at this time, the third driving value range is taken as the target value range, and the road adhesion degree level is the third level.

[0122] Further, when the vehicle working state is the ABS state, when the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in the continuous multiple time periods is greater than or equal to the first maximum acceleration threshold, at this time the identification parameter corresponding to the ABS state falls into the first anti-lock value range, the first anti-lock value range is taken as the target value range, and at this time the road adhesion degree level is the first level.

[0123] Further, when the maximum longitudinal deceleration in the continuous multiple time periods is less than the first maximum acceleration threshold and greater than or equal to the second maximum acceleration threshold, at this time the identification parameter corresponding to the ABS state falls into the second anti-lock value range, the second anti-lock value range is taken as the target value range, and at this time the road adhesion degree level is the second level. When the maximum longitudinal deceleration in the continuous multiple time periods is less than the second maximum acceleration threshold, at this time the identification parameter corresponding to the ABS state falls into the third anti-lock value range, and at this time the road adhesion degree level is the third level.

[0124] Further, in the ABS state, the road adhesion degree level is positively correlated with the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in the time period, the maximum longitudinal acceleration and the minimum longitudinal acceleration have equal absolute values but opposite signs.

[0125] Further, when the vehicle working state is the ASR state, when the maximum longitudinal acceleration in the continuous multiple time periods, such as three time periods, is greater than or equal to the first maximum acceleration threshold, the identification parameter corresponding to the ASR state falls into the first anti-slip value range, the first anti-slip value range is taken as the target value range, and at this time the road adhesion degree level is the first level.

[0126] Further, when the maximum longitudinal acceleration in the continuous three time periods is less than the first maximum acceleration threshold and greater than or equal to the second maximum acceleration threshold, the identification parameter corresponding to the ASR state falls into the second anti-slip value range, the second anti-slip value range is taken as the target value range, and at this time the road adhesion degree level is the second level. When the maximum longitudinal acceleration in the continuous three time periods is less than the second maximum acceleration threshold, the identification parameter corresponding to the ASR state falls into the third anti-slip value range, the third anti-slip value range is taken as the target value range, and at this time the road adhesion degree level is the third level.

[0127] Further, in the ASR state, the road adhesion degree level is positively correlated with the maximum longitudinal acceleration in the time period.

[0128] S207, when the vehicle working state is the target working mode, determining a corresponding road adhesion degree parameter according to the road adhesion degree level, the road adhesion degree parameter is positively correlated with the road adhesion degree level, and the target working mode includes the driving state, the driving state, the braking state and the unknown state.

[0129] Specifically, after determining the road adhesion degree level according to the vehicle working state and the corresponding identification parameter, it is detected whether the vehicle working state is the target working mode. If so, the corresponding target adhesion data set is obtained in the road adhesion database according to the target working mode.

[0130] Among them, for a plurality of different road adhesion degree levels, road types and corresponding road adhesion degree parameters pre-stored in the target adhesion data set, when the road adhesion degree level is the first level indicating high road adhesion degree, the corresponding road type is high adhesion road, and the road adhesion degree parameter corresponding to the high adhesion road is set to zero point eight.

[0131] Further, when the road adhesion degree level is the second level indicating medium-low road adhesion degree, the corresponding road type is medium-low adhesion road, and the road adhesion degree parameter corresponding to the medium-low adhesion road is set to zero point four; when the road adhesion degree level is the third level indicating low road adhesion degree, the corresponding road type is low adhesion road, and the road adhesion degree parameter corresponding to the low adhesion road is set to zero point two.

[0132] In the unknown state, the last identified road type and road adhesion degree parameter are the identified road type and road adhesion degree parameter. The identified road type and road adhesion degree parameter are output for the vehicle control unit to control the vehicle according to the road type and road adhesion degree parameter.

[0133] S208, when the vehicle working state is the mode other than the target working mode, the longitudinal acceleration is determined as the road adhesion degree parameter.

[0134] Specifically, when the vehicle working state is not the target working mode, that is, when the vehicle working state is the ABS state or the ASR state, the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in the longitudinal acceleration in the continuous time period is taken as the road adhesion degree parameter corresponding to the ABS state or the ASR state.

[0135] Further, for the road surface type in the ABS state or the ASR state, when the road surface adhesion degree level is the first level, the corresponding road surface type is high adhesion road surface, when the road surface adhesion degree level is the second level, the corresponding road surface type is medium-low adhesion road surface, and when the road surface adhesion degree level is the third level, the corresponding road surface type is low adhesion road surface. The identified road surface type and the road surface adhesion degree parameter are taken as outputs for the vehicle control unit to control the vehicle according to the road surface type and the road surface adhesion degree parameter.

[0136] The road surface adhesion recognition method provided by the embodiments of the present application determines the vehicle working state by acquiring the state information of the vehicle in the driving process, wherein the vehicle working state includes multiple different states, acquires the corresponding recognition parameter according to the vehicle working state, matches the recognition parameter corresponding to the vehicle working state with the corresponding parameter threshold value, obtains the road surface adhesion degree level in the vehicle working state, and determines the road surface adhesion degree parameter according to the road surface adhesion degree level and the vehicle working state. Therefore, the present application determines the corresponding adhesion degree parameter through different vehicle working states, thereby avoiding the defect that the kinetic equation cannot obtain the accurate road surface adhesion coefficient when the vehicle is driving stably, and improving the accuracy of obtaining the road surface adhesion coefficient.

[0137] Figure 4 The structural schematic diagram of the road surface adhesion recognition device provided by the present application is shown in FIG. 4, which comprises: Figure 5

[0138] The acquisition module 401 is configured to determine the vehicle working state according to the state information of the vehicle in the driving process, wherein the vehicle working state is one of the following: driving state, braking state, driving state, ABS state, ASR state, and unknown state.

[0139] The first processing module 402 is configured to acquire the corresponding recognition parameter according to the vehicle working state, wherein the recognition parameter of the driving state includes the fitting straight line slope between the total slip rate of each wheel on the vehicle and the longitudinal acceleration, the recognition parameter of the braking state includes the ratio between the longitudinal acceleration and the total slip rate, the recognition parameter of the driving state includes the longitudinal acceleration and the drive shaft slip rate, the recognition parameters of the ABS state and the ASR state are both the longitudinal acceleration, the drive shaft slip rate is the average value of the slip rate of the wheels on the drive shaft, and the slip rate of the wheels is the proportion of the difference between the wheel speed and the vehicle speed in the vehicle speed.

[0140] The second processing module 403 is configured to match the recognition parameter corresponding to the vehicle working state with the corresponding parameter threshold value, and obtain the road surface adhesion degree level in the vehicle working state. ​

[0141] The control module 404 is configured to determine a road adhesion degree parameter according to the road adhesion degree level and the vehicle working state.

[0142] In a possible implementation, the acquisition module 401 is configured to, when the driving state satisfies the following conditions: the absolute value of the longitudinal acceleration is less than a first acceleration threshold, the absolute value of the total slip ratio of each wheel of the vehicle is less than a first total slip ratio threshold, the accelerator pedal opening degree is less than a first accelerator opening degree threshold, the brake pedal opening degree is less than a first brake opening degree threshold, the vehicle speed is greater than or equal to a first vehicle speed threshold, the absolute value of the drive shaft slip ratio is less than a first drive slip ratio threshold, and the absolute value of the steering wheel rotation angle is less than a first rotation angle threshold;

[0143] The brake state satisfies the following conditions: the brake pedal opening degree is greater than or equal to a second brake opening degree threshold, the vehicle speed is greater than or equal to a second vehicle speed threshold, the ABS is not activated, the absolute value of the longitudinal acceleration is less than a second acceleration threshold, and the absolute value of the total slip ratio is less than a second total slip ratio threshold;

[0144] The drive state satisfies the following conditions: the ASR is not activated, the gear is not shifted, the drive shaft slip ratio is greater than or equal to a third drive slip ratio threshold, and the longitudinal acceleration is greater than or equal to a third acceleration threshold;

[0145] The ABS state satisfies the following conditions: the ABS is activated, the ABS activation signal indicates an activated state, and the ABS working state of at least two wheels is a pressure reduction state;

[0146] The ASR state satisfies the following condition: the ASR activation signal indicates an activated state.

[0147] In a possible implementation, the acquisition module 401 is configured to match the identification parameter corresponding to the vehicle working state with a corresponding parameter threshold to obtain the road adhesion degree level in the vehicle working state, including:

[0148] One or more value ranges are constructed according to the parameter threshold corresponding to each vehicle working state, and different value ranges correspond to different levels.

[0149] The value range in which the identification parameter is located is determined as a target value range, and the level corresponding to the target value range is taken as the road adhesion degree level.

[0150] In a possible implementation, the first processing module 402 is configured to, in the driving state, positively correlate the road adhesion degree level with a fitting straight line slope, and the fitting straight line slope is fitted with the total slip ratio as the horizontal axis and the longitudinal acceleration as the vertical axis.

[0151] In the braking state, the road adhesion level is positively correlated with the ratio;

[0152] In the driving state, the road adhesion level is positively correlated with the longitudinal acceleration and positively correlated with the drive shaft slip rate;

[0153] In the ABS state, the road adhesion level is positively correlated with the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in a time period, the maximum longitudinal acceleration and the minimum longitudinal acceleration have equal absolute values but opposite signs;

[0154] In the ASR state, the road adhesion level is positively correlated with the maximum longitudinal acceleration in a time period;

[0155] In the unknown state, the last identified road adhesion level is the road adhesion level identified this time.

[0156] In a possible implementation, the first processing module 402 is configured to: when the slope of the fitted straight line is greater than or equal to a first slope threshold, the road adhesion level is a first level; when the slope of the fitted straight line is less than the first slope threshold and greater than or equal to a second slope threshold, the road adhesion level is a second level; and when the slope of the fitted straight line is less than the second slope threshold, the road adhesion level is a third level;

[0157] In the braking state, when a plurality of consecutive ratios are greater than or equal to a first ratio threshold, the road adhesion level is a first level; when a plurality of consecutive ratios are less than the first ratio threshold and greater than or equal to a second ratio threshold, the road adhesion level is a second level; and when the ratio is less than the second ratio threshold, the road adhesion level is a third level;

[0158] In the driving state, when the longitudinal acceleration is greater than or equal to a fourth acceleration threshold for a plurality of consecutive times, the road adhesion level is a first level; when the longitudinal acceleration is less than the fourth acceleration threshold but greater than or equal to a fifth acceleration threshold for a plurality of consecutive times, and the drive shaft slip rate is greater than or equal to a fourth drive slip rate threshold for a plurality of consecutive times, the road adhesion level is a second level; otherwise, the road adhesion level is a third level;

[0159] In the ABS state, when the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in a plurality of continuous time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion degree level is a first level, when the maximum longitudinal deceleration in the plurality of continuous time periods is less than the first maximum acceleration threshold and greater than or equal to a second maximum acceleration threshold, the road adhesion degree level is a second level, and when the maximum longitudinal deceleration in the plurality of continuous time periods is less than the second maximum acceleration threshold, the road adhesion degree level is the third level.

[0160] In the ASR state, when the maximum longitudinal acceleration in a plurality of continuous time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion degree level is a first level, when the maximum longitudinal acceleration in the plurality of continuous time periods is less than the first maximum acceleration threshold and greater than or equal to a second maximum acceleration threshold, the road adhesion degree level is a second level, and when the maximum longitudinal acceleration in the plurality of continuous time periods is less than the second maximum acceleration threshold, the road adhesion degree level is the third level.

[0161] In a possible implementation, the control module 404 is configured to, when the vehicle working state is a target working mode, determine a corresponding road adhesion degree parameter according to the road adhesion degree level, the road adhesion degree parameter being positively correlated with the road adhesion degree level, and the target working mode including the driving state, the driving state, the braking state, and the unknown state.

[0162] When the vehicle working state is a mode other than the target working mode, the longitudinal acceleration is determined as the road adhesion degree parameter.

[0163] The road adhesion recognition device provided in the embodiment can execute the method provided in the method embodiment, and has similar implementation principles and technical effects. Details are not described herein.

[0164] Figure 5 A structural schematic diagram of an electronic device provided in the present application is shown in FIG. 1. ​ As shown in the figure, the electronic device 50 provided in the embodiment includes at least one processor 501 and a memory 502. Optionally, the device 50 further includes a communication component 503. The processor 501, the memory 502, and the communication component 503 are connected through a bus 504.

[0165] In the specific implementation process, the at least one processor 501 executes the computer execution instructions stored in the memory 502, so that the at least one processor 501 executes the method described above.

[0166] The specific implementation process of the processor 501 can refer to the method embodiments described above, which have similar implementation principles and technical effects, and thus will not be described here again.

[0167] In the above embodiments, it should be understood that the processor can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), etc. The general-purpose processor can be a microprocessor or any conventional processor, etc. The steps of the method disclosed in the application can be directly embodied as hardware processor execution, or executed by a combination of hardware and software modules in the processor.

[0168] The memory can include a random access memory (RAM), and can also include a non-volatile memory (NVM), such as at least one disk memory.

[0169] The bus can be an industry standard architecture (ISA) bus, a peripheral component (PCI) bus, an extended industry standard architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the convenience of representation, the bus in the drawings of the present application does not limit to only one bus or one type of bus.

[0170] The present application also provides a computer program product, comprising a computer program, which is executed by a processor to implement the above method.

[0171] The present application also provides a computer readable storage medium, which stores computer execution instructions, and when a processor executes the computer execution instructions, the above method is implemented.

[0172] The above-mentioned readable storage medium can be realized by any type of volatile or nonvolatile storage devices or their combinations, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk or optical disk. The readable storage medium can be any available medium that can be accessed by a general or special purpose computer.

[0173] An exemplary readable storage medium is coupled to the processor, so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be an integral part of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist as discrete components in the device.

[0174] The division of units is only a logical functional division, and in actual implementation, there can be another division manner, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0175] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on multiple network units. According to actual needs, part or all of the units can be selected to achieve the purpose of the embodiment scheme.

[0176] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit.

[0177] If the functions are implemented in the form of software function units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application or the parts of the technical solutions that essentially contribute to the prior art can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the embodiments of the method of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0178] It can be understood by those skilled in the art that all or part of the steps of the above-mentioned method embodiments can be completed by program instruction related hardware. The aforementioned program can be stored in a computer readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk, and various media that can store program codes.

[0179] Finally, it should be noted that: those skilled in the art will easily think of other embodiments of the present application after considering the specification and practicing the application disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application that follow the general principles of the present application and include common knowledge or conventional technical means in the art that are not disclosed in the present application, and is not limited to the precise structure described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the present application is only limited by the appended claims.

Claims

1. A road surface adhesion recognition method characterized by comprising: The method comprises: determining a vehicle working state according to state information of the vehicle during driving, the vehicle working state being one of the following: driving state, braking state, driving state, ABS state, ASR state, unknown state; obtaining corresponding identification parameters according to the vehicle working state, the identification parameters of the driving state including a fitting straight line slope between total slip rates of wheels on the vehicle and longitudinal acceleration, the identification parameters of the braking state including a ratio between the longitudinal acceleration and the total slip rate, the identification parameters of the driving state including the longitudinal acceleration and driving axle slip rate, the identification parameters of the ABS state and the ASR state both being the longitudinal acceleration, the driving axle slip rate being an average of slip rates of wheels on the driving axle, the slip rate of the wheel being a proportion of a difference between a wheel speed of the wheel and a vehicle speed in the vehicle speed; matching the identification parameters corresponding to the vehicle working state with corresponding parameter thresholds to obtain a road adhesion level of the vehicle working state; determining a road adhesion parameter according to the road adhesion level and the vehicle working state; the driving state satisfying the following conditions: an absolute value of the longitudinal acceleration being less than a first acceleration threshold, an absolute value of the total slip rate of the wheels on the vehicle being less than a first total slip rate threshold, an accelerator pedal opening being less than a first accelerator opening threshold, a brake pedal opening being less than a first brake opening threshold, a vehicle speed being greater than or equal to a first vehicle speed threshold, an absolute value of the driving axle slip rate being less than a first driving slip rate threshold, and an absolute value of a steering wheel angle being less than a first angle threshold; the braking state satisfying the following conditions: the brake pedal opening being greater than or equal to a second brake opening threshold, the vehicle speed being greater than or equal to a second vehicle speed threshold, ABS not being activated, the absolute value of the longitudinal acceleration being less than a second acceleration threshold, and the absolute value of the total slip rate being less than a second total slip rate threshold; the driving state satisfying the following conditions: ASR not being activated, no gear shifting, the driving axle slip rate being greater than or equal to a third driving slip rate threshold, and the longitudinal acceleration being greater than or equal to a third acceleration threshold; the ABS state satisfying the following conditions: ABS being activated, the ABS activation signal indicating an activated state, and ABS working states of at least two wheels being pressure reduction states; the ASR state satisfying the following condition: an ASR activation signal indicating an activated state; the unknown state being a state other than the driving state, the braking state, the driving state, the ABS state, and the ASR state.

2. The method of claim 1, wherein, The matching of the identification parameters corresponding to the vehicle working state with the corresponding parameter thresholds to obtain the road adhesion level of the vehicle working state comprises: constructing one or more value ranges according to the parameter thresholds corresponding to each vehicle working state, different value ranges corresponding to different levels; determining a target value range in which the identification parameter is located, and taking a level corresponding to the target value range as the road adhesion level.

3. The method of claim 2, wherein, in the driving state, the road adhesion level is positively correlated with the slope of the fitting straight line, the slope of the fitting straight line being fitted with the total slip rate as the horizontal axis and the longitudinal acceleration as the vertical axis; in the braking state, the road adhesion level is positively correlated with the ratio; in the driving state, the road adhesion level is positively correlated with the longitudinal acceleration and positively correlated with the drive axle slip rate; in the ABS state, the road adhesion level is positively correlated with the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in a time period, the maximum longitudinal acceleration and the minimum longitudinal acceleration having the same absolute value but opposite signs; in the ASR state, the road adhesion level is positively correlated with the maximum longitudinal acceleration in a time period; in the unknown state, the road adhesion level identified last time is the road adhesion level identified this time.

4. The method of claim 3, wherein, when the slope of the fitting straight line is greater than or equal to a first slope threshold, the road adhesion level is a first level, when the slope of the fitting straight line is less than the first slope threshold and greater than or equal to a second slope threshold, the road adhesion level is a second level, and when the slope of the fitting straight line is less than the second slope threshold, the road adhesion level is a third level; in the braking state, when a plurality of the ratios are greater than or equal to a first ratio threshold, the road adhesion level is a first level, when a plurality of the ratios are less than the first ratio threshold and greater than or equal to a second ratio threshold, the road adhesion level is a second level, and when the ratio is less than the second ratio threshold, the road adhesion level is a third level; in the driving state, when the longitudinal acceleration is greater than or equal to a fourth acceleration threshold for a plurality of times, the road adhesion level is a first level, when the longitudinal acceleration is less than the fourth acceleration threshold but greater than or equal to a fifth acceleration threshold for a plurality of times and the drive axle slip rate is greater than or equal to a fourth drive slip rate threshold for a plurality of times, the road adhesion level is a second level, and otherwise, the road adhesion level is a third level; in the ABS state, when the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in a plurality of time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion level is a first level, when the maximum longitudinal deceleration in a plurality of time periods is less than the first maximum acceleration threshold and greater than or equal to a second maximum acceleration threshold, the road adhesion level is a second level, and when the maximum longitudinal deceleration in a plurality of time periods is less than the second maximum acceleration threshold, the road adhesion level is the third level; In the ASR state, when the maximum longitudinal acceleration of the continuous multiple time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion level is a first level, when the maximum longitudinal acceleration of the continuous multiple time periods is less than the first maximum acceleration threshold and greater than or equal to a second maximum acceleration threshold, the road adhesion level is a second level, and when the maximum longitudinal acceleration of the continuous multiple time periods is less than the second maximum acceleration threshold, the road adhesion level is the third level.

5. The method according to any one of claims 1 to 4, characterized in that, The determination of the road adhesion level parameter according to the road adhesion level and the vehicle working state comprises: When the vehicle working state is a target working mode, a corresponding road adhesion level parameter is determined according to the road adhesion level, the road adhesion level parameter being positively correlated with the road adhesion level, and the target working mode comprising the driving state, the driving state, the braking state and the unknown state; When the vehicle working state is a mode other than the target working mode, the longitudinal acceleration is determined as the road adhesion level parameter.

6. A road surface adhesion recognition device characterized by comprising: Comprise: The acquisition module is used for determining a vehicle working state according to state information of the vehicle in the driving process, and the vehicle working state is one of the following: driving state, braking state, driving state, anti-lock braking system (ABS) state, acceleration slip regulation (ASR) state and unknown state; The first processing module is used for acquiring a corresponding identification parameter according to the vehicle working state, the identification parameter of the driving state comprising a fitting straight line slope between a total slip rate of each wheel on the vehicle and the longitudinal acceleration, the identification parameter of the braking state comprising a ratio between the longitudinal acceleration and the total slip rate, the identification parameter of the driving state comprising the longitudinal acceleration and a drive shaft slip rate, the identification parameters of the ABS state and the ASR state both being the longitudinal acceleration, the drive shaft slip rate being an average value of slip rates of wheels on the drive shaft, and the slip rate of the wheel being a proportion of a difference between a wheel speed and a vehicle speed in the vehicle speed; The second processing module is used for matching the identification parameter corresponding to the vehicle working state with a corresponding parameter threshold to obtain a road adhesion level in the vehicle working state; The control module is used for determining a road adhesion level parameter according to the road adhesion level and the vehicle working state; The driving state satisfies the following conditions: the absolute value of the longitudinal acceleration is less than a first acceleration threshold, the absolute value of the total slip rate of each wheel on the vehicle is less than a first total slip rate threshold, the opening degree of the accelerator pedal is less than a first accelerator opening degree threshold, the opening degree of the brake pedal is less than a first brake opening degree threshold, the vehicle speed is greater than or equal to a first vehicle speed threshold, the absolute value of the drive shaft slip rate is less than a first drive slip rate threshold, and the absolute value of the steering wheel angle is less than a first steering angle threshold. the brake state satisfies the following conditions: the brake pedal opening is greater than or equal to a second brake opening threshold, the vehicle speed is greater than or equal to a second vehicle speed threshold, ABS is not activated, the absolute value of the longitudinal acceleration is less than a second acceleration threshold, and the absolute value of the total slip ratio is less than a second total slip ratio threshold; the drive state satisfies the following conditions: ASR is not activated, no gear shifting is performed, the drive axle slip ratio is greater than or equal to a third drive slip ratio threshold, and the longitudinal acceleration is greater than or equal to a third acceleration threshold; the ABS state satisfies the following conditions: ABS is activated, the ABS activation signal indicates an activated state, and the ABS working state of at least two wheels is a pressure reduction state; the ASR state satisfies the following condition: an ASR activation signal indicates an activated state; the unknown state is a state other than the driving state, the brake state, the drive state, the ABS state, and the ASR state.

7. An electronic device, comprising: comprising: a processor, and a memory connected to the processor in communication; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the method according to any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are executed by the processor to implement the method according to any one of claims 1 to 5.

9. A computer program product, characterised in that, comprising a computer program, which, when executed by a processor, implements the method according to any one of claims 1 to 5.

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