Road surface attachment identification method and device, storage medium and product

Abstract

The invention provides a road adhesion identification method and device, a storage medium and a product. According to the method, the working states of the vehicle are determined by obtaining the state information of the vehicle in the driving process, the working states of the vehicle comprise multiple different states, corresponding identification parameters are obtained according to the working states of the vehicle, the identification parameters corresponding to the working states of the vehicle are matched with corresponding parameter thresholds, and the working states of the vehicle are determined. And obtaining a road adhesion degree grade under the vehicle working state, and determining a road adhesion degree parameter according to the road adhesion degree grade and the vehicle working state. Therefore, the corresponding adhesion degree parameters are determined according to different vehicle working states, so that the defect that an accurate road adhesion coefficient cannot be obtained by a kinetic equation when the vehicle runs stably is overcome, and the accuracy of obtaining the road adhesion coefficient is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a road adhesion recognition method, device, storage medium and product. Background Art

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

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

[0004] The present application provides a road adhesion identification method, device, storage medium and product to achieve the effect of solving the defect of existing solutions in that the road adhesion coefficient cannot be accurately obtained when the vehicle is in a constant speed state.

[0005] In a first aspect, an embodiment of the present application provides a road surface adhesion recognition method, comprising:

[0006] Determine the working state of the vehicle according to the state information of the vehicle during driving, wherein the working state of the vehicle is one of the following: driving state, braking state, driving state, anti-lock braking system ABS state, acceleration anti-skid system ASR state, unknown state;

[0007] Acquire corresponding identification parameters according to the working state of the vehicle, the identification parameters of the driving state include: the slope of the fitted straight line between the total slip rate of each wheel on the vehicle and the longitudinal acceleration, the identification parameters of the braking state include: the ratio between the longitudinal acceleration and the total slip rate, the identification parameters of the driving state include: 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 slip rate of the wheels on the drive shaft, and 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] Matching the identification parameter corresponding to the vehicle working state with the corresponding parameter threshold to obtain the road adhesion level under the vehicle working state;

[0009] A road adhesion parameter is determined according to the road adhesion level and the vehicle operating state.

[0010] In a possible implementation manner, 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 accelerator pedal opening is less than a first acceleration 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 rate is less than a first drive slip rate threshold, and the absolute value of the steering wheel angle is less than a first angle threshold;

[0011] The braking 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;

[0012] The driving state satisfies the following conditions: ASR is not activated, 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;

[0013] The ABS state satisfies the following conditions: the ABS is activated, wherein 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 decompression state;

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

[0015] In a possible implementation manner, matching the identification parameter corresponding to the vehicle working state with a corresponding parameter threshold to obtain a road surface adhesion level under the vehicle working state includes:

[0016] Construct one or more value ranges according to the parameter threshold corresponding to each of the vehicle operating states, and different value ranges correspond to different levels;

[0017] The value range of the identification parameter is determined as a target value range, and the level corresponding to the target value range is used as the road surface adhesion level.

[0018] In a possible implementation manner, in the driving state, the road adhesion level is positively correlated with the slope of the fitting line, and the slope of the fitting line is obtained by fitting with the total slip rate as the horizontal axis and the longitudinal acceleration as the vertical axis;

[0019] In the braking state, the road surface adhesion 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 the time period, and 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 the time period;

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

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

[0025] In the braking state, when a plurality of the ratios are continuously greater than or equal to a first ratio threshold, the road surface adhesion level is a first level; when a plurality of the ratios are continuously less than the first ratio threshold and greater than or equal to a second ratio threshold, the road surface adhesion level is a second level; and when the ratio is less than the second ratio threshold, the road surface 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 value for multiple consecutive times, the road adhesion level is the first level; when the longitudinal acceleration is less than the fourth acceleration threshold value but greater than or equal to a fifth acceleration threshold value for multiple consecutive times, and the drive shaft slip rate is greater than or equal to a fourth drive slip rate threshold value for multiple consecutive times, the road adhesion level is the second level; otherwise, the road adhesion level is the third level;

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

[0029] In a possible implementation manner, when the vehicle operating state is a target operating mode, a corresponding road surface adhesion parameter is determined according to the road surface adhesion level, the road surface adhesion parameter is positively correlated with the road surface adhesion level, and the target operating mode includes: the driving state, the driving state, the braking state, and the unknown state;

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

[0031] In a second aspect, an embodiment of the present application provides a road surface adhesion recognition device, comprising:

[0032] An acquisition module is used to determine the working state of the vehicle according to the state information of the vehicle during driving, wherein the working state of the vehicle is one of the following: driving state, braking state, driving state, anti-lock braking system ABS state, acceleration anti-skid system ASR state, and unknown state;

[0033] a first processing module, configured to obtain corresponding identification parameters according to the working state of the vehicle, wherein the identification parameters of the driving state include: the slope of a fitted straight line between the total slip rate of each wheel on the vehicle and the longitudinal acceleration, the identification parameters of the braking state include: the ratio between the longitudinal acceleration and the total slip rate, the identification parameters of the driving state include: 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 slip rate of the wheels on the drive shaft, and the wheel slip rate is the proportion of the difference between the wheel speed and the vehicle speed in the vehicle speed;

[0034] A second processing module is used to match the identification parameter corresponding to the vehicle working state with the corresponding parameter threshold to obtain the road adhesion level under the vehicle working state;

[0035] A control module is used to determine a road surface adhesion parameter according to the road surface adhesion level and the vehicle operating state.

[0036] In a possible implementation, the acquisition module satisfies the following conditions in the driving state: the absolute value of the longitudinal acceleration is less than the first acceleration threshold, the absolute value of the total slip rate of each wheel on the vehicle is less than the first total slip rate threshold, the accelerator pedal opening is less than the first acceleration opening threshold, the brake pedal opening is less than the first brake opening threshold, the vehicle speed is greater than or equal to the first vehicle speed threshold, the absolute value of the drive shaft slip rate is less than the first drive slip rate threshold, and the absolute value of the steering wheel angle is less than the first angle threshold;

[0037] The braking 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;

[0038] The driving state satisfies the following conditions: ASR is not activated, 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;

[0039] The ABS state satisfies the following conditions: the ABS is activated, wherein 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 decompression state;

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

[0041] In a possible implementation, the acquisition module is specifically used to match the identification parameter corresponding to the vehicle working state with the corresponding parameter threshold to obtain the road adhesion level under the vehicle working state, including:

[0042] Construct one or more value ranges according to the parameter threshold corresponding to each of the vehicle operating states, and different value ranges correspond to different levels;

[0043] The value range of the identification parameter is determined as a target value range, and the level corresponding to the target value range is used as the road surface adhesion level.

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

[0045] In the braking state, the road surface adhesion 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 the time period, and the maximum longitudinal acceleration and the minimum longitudinal acceleration are equal in absolute value but opposite in sign;

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

[0049] In the unknown state, the road adhesion level identified last time 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 fitted straight line is greater than or equal to a first slope threshold, the road surface adhesion level is the 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 surface adhesion level is the second level; when the slope of the fitted straight line is less than the second slope threshold, the road surface adhesion level is the third level;

[0051] In the braking state, when a plurality of the ratios are continuously greater than or equal to a first ratio threshold, the road surface adhesion level is a first level; when a plurality of the ratios are continuously less than the first ratio threshold and greater than or equal to a second ratio threshold, the road surface adhesion level is a second level; and when the ratio is less than the second ratio threshold, the road surface 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 value for multiple consecutive times, the road adhesion level is the first level; when the longitudinal acceleration is less than the fourth acceleration threshold value but greater than or equal to a fifth acceleration threshold value for multiple consecutive times, and the drive shaft slip rate is greater than or equal to a fourth drive slip rate threshold value for multiple consecutive times, the road adhesion level is the second level; otherwise, the road adhesion level is the third level;

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

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

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

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

[0058] The memory stores computer-executable instructions;

[0059] The processor executes the computer-executable 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, in which computer-readable storage medium is stored computer-executable instructions, and the computer-executable instructions are used to implement the method described above when executed by a processor.

[0061] In a fifth aspect, an embodiment of the present application provides a computer program product, characterized in that it includes a computer program that implements the above method when executed by a processor.

[0062] The road adhesion identification method, device, storage medium and product provided in the embodiments of the present application determine the working state of the vehicle by acquiring the state information of the vehicle during driving, wherein the working state of the vehicle includes a plurality of different states, obtains the corresponding identification parameters according to the working state of the vehicle, matches the identification parameters corresponding to the working state of the vehicle with the corresponding parameter threshold, obtains the road adhesion level under the working state of the vehicle, and determines the road adhesion parameters according to the road adhesion level and the working state of the vehicle. Therefore, the present application determines the corresponding adhesion parameters according to different working states of the vehicle, thereby avoiding the defect that the dynamic equation cannot obtain the accurate road adhesion coefficient when the vehicle is driving steadily, and improves the accuracy of obtaining the road adhesion coefficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] The accompanying drawings, which are incorporated in and constitute a part of this 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 A schematic diagram of the basic framework provided for this application;

[0065] Figure 2 Schematic diagram of the process of road adhesion identification method provided in this application Figure 1 ;

[0066] Figure 3 Schematic diagram of the process of road adhesion identification method provided in this application Figure 2 ;

[0067] Figure 4 A schematic diagram of the structure of the road surface adhesion identification device provided in this application;

[0068] Figure 5 A schematic diagram of the structure of the electronic device provided in this application.

[0069] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0070] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0071] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in one or more embodiments of this specification are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards, and corresponding operation entrances shall be provided for users to choose to authorize or refuse.

[0072] It should be noted that in the embodiments of the present application, certain software, components, models and other existing solutions in the industry may be mentioned, and they should be regarded as exemplary. Their purpose is only to illustrate the feasibility of implementing the technical solution 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 car. The road adhesion coefficient is affected by many factors, including road material, dry or wet conditions, tire structure, tread pattern and vehicle speed.

[0074] Existing solutions for obtaining the road adhesion coefficient include 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 parameters affecting the adhesion coefficient are measured through 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, by combining multiple sensor data, such as the sensor data of the vehicle-mounted camera and the high-precision map, and processing the acquired sensor data through a filtering algorithm, the movement state of the wheel is determined based on the processed sensor data, and the road adhesion coefficient is estimated in real time based on the movement state.

[0075] A study of the working process of the above-mentioned existing scheme found that when establishing a tire mechanics model, only when there is obvious wheel slippage, such as when the vehicle accelerates or decelerates suddenly, can an accurate tire mechanics model be established based on the vehicle slip data, so that the road adhesion coefficient can be obtained based on the established tire mechanics model. At this time, the observability of the road adhesion coefficient is high; when the vehicle is driving smoothly, such as when the vehicle is driving at a constant speed or accelerating or decelerating slowly, there is no obvious vehicle slippage data, and an accurate and appropriate 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] In view of this, the present application provides a road adhesion identification method, which determines the vehicle working state by acquiring the state information of the vehicle during driving, wherein the vehicle working state includes a plurality of different states, obtains the corresponding identification parameters according to the vehicle working state, matches the identification parameters corresponding to the vehicle working state with the corresponding parameter threshold, obtains the road adhesion level under the vehicle working state, and determines the road adhesion parameters according to the road adhesion level and the vehicle working state. Therefore, the present application determines the corresponding adhesion parameters through different vehicle working states, thereby avoiding the defect that the dynamic equation cannot obtain the accurate road adhesion coefficient when the vehicle is driving steadily, and improves the accuracy of obtaining the road adhesion coefficient.

[0077] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are 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 may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0078] Figure 1 The basic framework diagram provided for this application is as follows: Figure 2 Schematic diagram of the process of road adhesion identification method provided in this application Figure 1 , combined with Figure 1 and Figure 2 As shown, the method includes:

[0079] S101. Determine a vehicle operating state according to state information of the vehicle during driving, where the vehicle operating state is one of the following: driving state, braking state, driving state, anti-lock braking system (ABS) state, acceleration anti-skid system (ASR) state, or unknown state.

[0080] Specifically, when the vehicle is driving normally, the vehicle status information at this time is obtained through various on-board sensors, where the vehicle status information includes the wheel speed of each wheel, longitudinal acceleration, total slip rate of each wheel, accelerator pedal opening, brake pedal opening, vehicle speed, drive shaft slip rate, steering wheel angle, ABS activation status (Anti-lock Braking System) and ASR (Acceleration Slip Regulation) activation status. Unknown status refers to the status other than driving status, braking status, driving status, ABS status and ASR status.

[0081] Furthermore, for longitudinal acceleration, after the vehicle obtains acceleration signals and vehicle speed signals through sensors such as an inertial measurement unit (IMU), the acceleration signals and vehicle speed signals are filtered through a Kalman filter algorithm to obtain filtered longitudinal acceleration and vehicle speed.

[0082] Furthermore, the slip rate of each wheel is calculated based on the wheel speed and vehicle speed, the sum of the slip rates of each wheel is obtained as the total slip rate, and the average slip rate of the two wheels on the rear axle is obtained as the drive shaft slip rate.

[0083] S102. Acquire corresponding identification parameters according to the working state of the vehicle, wherein the identification parameters of the driving state include: the slope of a fitted straight line between the total slip rate of each wheel on the vehicle and the longitudinal acceleration, the identification parameters of the braking state include: the ratio between the longitudinal acceleration and the total slip rate, the identification parameters of the driving state include: 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 slip rate of the wheels on the drive shaft, and the slip rate 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 operating state according to the state information, in the acquired state information, the corresponding state information is acquired according to the vehicle operating state, and the corresponding identification parameter is acquired according to the corresponding state information.

[0085] Furthermore, for the identification parameters of the driving state, multiple total slip rates and corresponding longitudinal accelerations within a preset driving time in the driving state are obtained, and linear fitting is performed on the multiple total slip rates and corresponding longitudinal accelerations through the recursive least squares method, and the slope of the fitting line is obtained as the identification parameter of the driving state.

[0086] Furthermore, for the identification parameters of the braking state, multiple longitudinal accelerations and corresponding total slip rates are obtained during the preset continuous braking time in the braking state, and the ratios of the multiple longitudinal accelerations to the corresponding total slip rates are recorded as the identification parameters of the braking state.

[0087] S103: Match the identification parameter corresponding to the vehicle working state with the corresponding parameter threshold to obtain the road adhesion level under the vehicle working state.

[0088] Specifically, after determining the vehicle working state and obtaining the identification parameters corresponding to the vehicle working state, the corresponding parameter threshold is obtained in the threshold database according to the vehicle working state. After obtaining the corresponding parameter threshold, the identification parameters corresponding to the vehicle working state are compared with the obtained parameter threshold, and the road adhesion level under the corresponding vehicle working state is determined according to the comparison result. Among them, the threshold database pre-associates and stores multiple groups of different vehicle working states and corresponding parameter thresholds.

[0089] S104: Determine a road surface adhesion parameter according to the road surface adhesion level and the vehicle operating state.

[0090] Specifically, after determining the road adhesion level according to the vehicle working state and the corresponding identification parameters, in the road adhesion database, the corresponding adhesion data group is obtained according to the vehicle working state, in the adhesion data group, the road type is confirmed according to the road adhesion level, and the corresponding road adhesion parameters are obtained according to the road type. The obtained road type and road adhesion parameters are used as outputs for the vehicle control unit to control the vehicle according to the road type and road adhesion parameters.

[0091] The road adhesion database stores a plurality of vehicle operating states and corresponding adhesion data groups in association with each other in advance, and the adhesion data group stores a plurality of different road adhesion levels, road types and corresponding road adhesion parameters in association with each other in advance.

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

[0093] Figure 3 Schematic diagram of the process of road adhesion identification method provided in this application Figure 2 ,like Figure 3 As shown, in this embodiment Figure 1 Based on the embodiment, a road surface adhesion recognition method is described in detail, and the method includes:

[0094] S201. Determine a vehicle operating state according to state information of the vehicle during driving.

[0095] Specifically, after obtaining the state information of the vehicle in motion through each vehicle-mounted sensor, the working state of the vehicle at this time is determined according to the state information. When the absolute value of the longitudinal acceleration in the state information is less than the first acceleration threshold, the absolute value of the total slip ratio is less than the first total slip ratio threshold, the accelerator pedal opening is less than the first acceleration opening threshold, the brake pedal opening is less than the first brake opening threshold, the vehicle speed is greater than or equal to the first vehicle speed threshold, the absolute value of the drive shaft slip ratio is less than the first drive slip ratio threshold, and the absolute value of the steering wheel angle is less than the first angle threshold, it is determined that the vehicle is in the driving state at this time.

[0096] Further, when the brake pedal opening in the status 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 status indicates that the ABS is not activated, the absolute value of the longitudinal acceleration is less than the second acceleration threshold, and the absolute value of the total slip rate is less than the second total slip rate threshold, it is determined that the vehicle is in a braking state at this time.

[0097] Further, when the ASR activation state in the state information indicates that the ASR is not activated, the gear is not shifted, the drive shaft slip rate is greater than or equal to the third drive slip rate threshold, and the longitudinal acceleration is greater than or equal to the third acceleration threshold, it is determined that the vehicle is in a driving state at this time.

[0098] Further, when the ABS activation status in the status information indicates that the ABS is activated, the ABS activation includes an ABS activation signal indicating that it is in an activated state, and the ABS working state of at least two wheels is a decompression state, it is determined that the vehicle is in an ABS state at this time; when the ASR activation status in the status information indicates that the ASR is activated, it is determined that the vehicle is in an ASR state at this time.

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

[0100] S202. Construct one or more value ranges according to the parameter threshold corresponding to each vehicle operating state, where different value ranges correspond to different levels.

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

[0102] Furthermore, for parameter thresholds of driving status such as the first slope threshold, a numerical range greater than or equal to the first slope threshold is used as the first driving value range of the driving status, a numerical range less than or equal to the first slope threshold and greater than or equal to the second slope threshold is used as the second driving value range of the driving status, and a numerical range less than the second slope threshold is used as the third driving value range of the driving status.

[0103] Furthermore, for parameter thresholds of the braking state such as the first ratio threshold, a numerical range greater than or equal to the first ratio threshold will be used as the first braking value range of the braking state, a numerical range less than the first ratio threshold and greater than or equal to the second ratio threshold will be used as the second braking value range of the braking state, and a numerical range less than the second ratio threshold will be used as the third braking value range of the braking state.

[0104] Furthermore, for parameter thresholds of the driving state, such as the fourth acceleration threshold and the fourth driving slip rate threshold, a numerical range that is greater than or equal to the fourth acceleration threshold for multiple times, such as three times, is used as the first driving value range of the driving state; when it is less than the fourth acceleration threshold but greater than or equal to the fifth acceleration threshold, a numerical range that is greater than or equal to the fourth driving slip rate threshold for multiple times is used as the second driving value range of the driving state; and the numerical ranges corresponding to other situations are used as the third driving value range of the driving state.

[0105] Furthermore, for parameter thresholds of the ABS state, such as the first maximum acceleration threshold and the second maximum acceleration threshold, a numerical range greater than the first maximum acceleration threshold will be used as the first anti-lock braking value range of the ABS state, a numerical range less than the first maximum acceleration threshold and greater than or equal to the second maximum acceleration threshold will be used as the second anti-lock braking value range of the ABS state, and a numerical range less than the second maximum acceleration threshold will be used as the third anti-lock braking value range of the ABS state.

[0106] Furthermore, for the parameter thresholds of the ASR state such as the first maximum acceleration threshold and the second maximum acceleration threshold, a numerical range greater than or equal to the first maximum acceleration threshold will be used as the first anti-skid value range of the ASR state, a numerical range less than the first maximum acceleration threshold and greater than or equal to the second maximum acceleration threshold will be used as the second anti-skid value range of the ASR state, and a numerical range less than the second maximum acceleration threshold will be used as the third anti-skid value range of the ASR state.

[0107] S203: Determine the value range of the identification parameter as a target value range.

[0108] Specifically, after determining the vehicle operating state and obtaining the identification parameter corresponding to the vehicle operating state, the identification parameter corresponding to the vehicle operating state is detected to determine the value range in which the identification parameter falls, and the value range in which it falls is used 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 used as the road adhesion 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 level is the 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 level is the second level; when the slope of the fitting straight line is less than the second slope threshold, the road surface adhesion level is the third level.

[0110] Specifically, when the vehicle is in a driving state, when the identification parameter corresponding to the driving state, that is, the slope of the fitting straight line is greater than or equal to a first slope threshold, the identification parameter of the driving state falls into a first driving value range. At this time, the first driving value range is used as the target value range, and the road adhesion level is the first level.

[0111] Furthermore, when the identification parameter corresponding to the driving state, that is, 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 used as the target value range, and the road adhesion level is the second level.

[0112] Furthermore, when the identification parameter corresponding to the driving state, that is, 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 used as the target value range, and the road adhesion level is the third level.

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

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

[0115] Specifically, when the vehicle is in a braking state, after a preset braking time, when the identification parameter corresponding to the braking state, that is, the ratio between multiple longitudinal accelerations and the corresponding total slip rate, is greater than or equal to a first ratio threshold for three consecutive times, the identification parameter of the braking state falls into a first braking value range, and the first braking value range is used as the target value range. At this time, the road adhesion level is the first level.

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

[0117] Further, when the ratio between the longitudinal acceleration and the corresponding total slip ratio is less than the second ratio threshold, the identification parameter of the braking state falls into the third braking value range, and the third braking value range is used as the target value range, and the road adhesion level is the third level. In the braking state, the road adhesion 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 for multiple consecutive times, the road adhesion level is the first level; when the longitudinal acceleration is less than the fourth acceleration threshold but greater than or equal to the fifth acceleration threshold for multiple consecutive times, and the drive shaft slip rate is greater than or equal to the fourth drive slip rate threshold for multiple consecutive times, the road adhesion level is the second level; otherwise, the road adhesion level is the third level.

[0119] Specifically, when the vehicle is in a driving state, after a preset driving time, the identification parameters corresponding to the driving state, i.e., multiple longitudinal accelerations and the corresponding drive shaft slip rate, when the longitudinal acceleration is greater than or equal to the fourth acceleration threshold for three consecutive times, the identification parameters of the driving state fall into the first driving value range, and the first driving value range is used as the target value range. At this time, the road adhesion level is the first level.

[0120] Furthermore, when the longitudinal acceleration is less than the fourth acceleration threshold but greater than or equal to the fifth acceleration threshold, and the drive shaft slip is greater than or equal to the fourth drive slip threshold for three consecutive times, the identification parameters of the driving state fall into the second driving value range, and the second driving value range is used as the target value range. At this time, the road adhesion level is the second level.

[0121] Further, when the identification parameters of the driving state do not fall within the first driving value range and the second driving value range, it is determined that the identification parameters of the driving state at this time fall within the third driving value range, and the third driving value range is used as the target value range. At this time, the road adhesion level is the third level.

[0122] Furthermore, when the vehicle is in the ABS state, when the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration of multiple consecutive time periods is greater than or equal to the first maximum acceleration threshold, the identification parameter corresponding to the ABS state falls into the first anti-lock braking value range, and the first anti-lock braking value range is used as the target value range. At this time, the road adhesion level is the first level.

[0123] Further, when the maximum longitudinal deceleration of multiple consecutive 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 ABS state falls into the second anti-lock value range, the second anti-lock value range is used as the target value range, and the road adhesion level is the second level. When the maximum longitudinal deceleration of multiple consecutive time periods is less than the second maximum acceleration threshold, the identification parameter corresponding to the ABS state falls into the third anti-lock value range, and the road adhesion level is the third level.

[0124] Furthermore, in the ABS state, the road adhesion level is positively correlated with the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration in the time period, and the maximum longitudinal acceleration and the minimum longitudinal acceleration are equal in absolute value but opposite in sign.

[0125] Furthermore, when the vehicle operating state is the ASR state, when the maximum longitudinal acceleration of multiple consecutive time periods such as three sections is greater than or equal to the first maximum acceleration threshold, the identification parameters corresponding to the ASR state fall into the first anti-skid value range, and the first anti-skid value range is used as the target value range. At this time, the road adhesion level is the first level.

[0126] Further, when the maximum longitudinal acceleration of three consecutive 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-skid value range, and the second anti-skid value range is used as the target value range. At this time, the road surface adhesion level is the second level. When the maximum longitudinal acceleration of three consecutive time periods is less than the second maximum acceleration threshold, the identification parameter corresponding to the ASR state falls into the third anti-skid value range, and the third anti-skid value range is used as the target value range. At this time, the road surface adhesion level is the third level.

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

[0128] S207. When the vehicle operating state is a target operating mode, a corresponding road adhesion parameter is determined according to the road adhesion level, wherein the road adhesion parameter is positively correlated with the road adhesion level, and the target operating mode includes: the traveling state, the driving state, the braking state and the unknown state.

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

[0130] Among them, for the multiple different road adhesion levels, road types and corresponding road adhesion parameters pre-stored in the target adhesion data group, when the road adhesion level is the first level indicating a high road adhesion level, the corresponding road type is a high-adhesion road surface, and the road adhesion parameter corresponding to the high-adhesion road surface is set to 0.8.

[0131] Furthermore, when the road surface adhesion level is the second level indicating medium-low adhesion of the road surface, the corresponding road surface type is a medium-low adhesion road surface, and the road surface adhesion parameter corresponding to the medium-low adhesion road surface is set to 0.4; when the road surface adhesion level is the third level indicating low adhesion of the road surface, the corresponding road surface type is a low adhesion road surface, and the road surface adhesion parameter corresponding to the low adhesion road surface is set to 0.2.

[0132] In an unknown state, the road surface type and road surface adhesion parameters identified last time are used as the road surface type and road surface adhesion parameters identified this time. The identified road surface type and road surface adhesion parameters are used as outputs for the vehicle control unit to control the vehicle according to the road surface type and road surface adhesion parameters.

[0133] S208: When the vehicle operating state is a mode other than the target operating mode, determine the longitudinal acceleration as the road adhesion parameter.

[0134] Specifically, when the vehicle operating state is not the target operating mode, that is, when the vehicle operating state is the ABS state or the ASR state, among the longitudinal accelerations in multiple consecutive time periods, the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration is used as the road adhesion 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 level is the first level, the corresponding road surface type is a high adhesion road surface, when the road surface adhesion level is the second level, the corresponding road surface type is a medium-low adhesion road surface, and when the road surface adhesion level is the third level, the corresponding road surface type is a low adhesion road surface. The identified road surface type and road surface adhesion parameter are used as outputs for the vehicle control unit to control the vehicle according to the road surface type and the road surface adhesion parameter.

[0136] The road adhesion identification method provided in the embodiment of the present application determines the working state of the vehicle by acquiring the state information of the vehicle during driving, wherein the working state of the vehicle includes a plurality of different states, obtains the corresponding identification parameters according to the working state of the vehicle, matches the identification parameters corresponding to the working state of the vehicle with the corresponding parameter threshold, obtains the road adhesion level under the working state of the vehicle, and determines the road adhesion parameters according to the road adhesion level and the working state of the vehicle. Therefore, the present application determines the corresponding adhesion parameters according to different working states of the vehicle, thereby avoiding the defect that the dynamic equation cannot obtain the accurate road adhesion coefficient when the vehicle is driving steadily, and improves the accuracy of obtaining the road adhesion coefficient.

[0137] Figure 4 The schematic diagram of the structure of the road surface adhesion identification device provided in this application is as follows: Figure 4 As shown, the device 40 includes:

[0138] The acquisition module 401 is used to determine the vehicle working state according to the state information of the vehicle during driving, and the vehicle working state is one of the following: driving state, braking state, driving state, anti-lock braking system ABS state, acceleration anti-skid system ASR state, and unknown state.

[0139] The first processing module 402 is used to obtain corresponding identification parameters according to the working state of the vehicle, the identification parameters of the driving state include: the slope of the fitted straight line between the total slip rate of each wheel on the vehicle and the longitudinal acceleration, the identification parameters of the braking state include: the ratio between the longitudinal acceleration and the total slip rate, the identification parameters of the driving state include: 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 slip rate of the wheels on the drive shaft, and the slip rate of the wheel 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 used to match the identification parameter corresponding to the vehicle working state with the corresponding parameter threshold to obtain the road adhesion level under the vehicle working state.

[0141] The control module 404 is used to determine a road surface adhesion parameter according to the road surface adhesion level and the vehicle operating state.

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

[0143] The braking 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;

[0144] The driving state satisfies the following conditions: ASR is not activated, 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, wherein 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 decompression 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 used to match the identification parameter corresponding to the vehicle working state with the corresponding parameter threshold to obtain the road adhesion level under the vehicle working state, including:

[0148] Construct one or more value ranges according to the parameter threshold corresponding to each of the vehicle operating states, and different value ranges correspond to different levels;

[0149] The value range of the identification parameter is determined as a target value range, and the level corresponding to the target value range is used as the road surface adhesion level.

[0150] In a possible implementation, the first processing module 402 is configured to, in the driving state, positively correlate the road adhesion level with the slope of the fitting line, where the slope of the fitting line is obtained by fitting with the total slip rate as the horizontal axis and the longitudinal acceleration as the vertical axis;

[0151] In the braking state, the road surface 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 the time period, and the maximum longitudinal acceleration and the minimum longitudinal acceleration are equal in absolute value but opposite in sign;

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

[0155] In the unknown state, the road adhesion level identified last time 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, set the road surface adhesion level to 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, set the road surface adhesion level to a second level; and when the slope of the fitted straight line is less than the second slope threshold, set the road surface adhesion level to a third level;

[0157] In the braking state, when a plurality of the ratios are continuously greater than or equal to a first ratio threshold, the road surface adhesion level is a first level; when a plurality of the ratios are continuously less than the first ratio threshold and greater than or equal to a second ratio threshold, the road surface adhesion level is a second level; and when the ratio is less than the second ratio threshold, the road surface 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 value for multiple consecutive times, the road adhesion level is the first level; when the longitudinal acceleration is less than the fourth acceleration threshold value but greater than or equal to a fifth acceleration threshold value for multiple consecutive times, and the drive shaft slip rate is greater than or equal to a fourth drive slip rate threshold value for multiple consecutive times, the road adhesion level is the second level; otherwise, the road adhesion level is the third level;

[0159] In the ABS state, when the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration of multiple consecutive time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion level is the first level; when the maximum longitudinal deceleration of multiple 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 the second level; when the maximum longitudinal deceleration of multiple consecutive time periods is less than the second maximum acceleration threshold, the road adhesion level is the third level;

[0160] In the ASR state, when the maximum longitudinal acceleration of multiple consecutive time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion level is the first level; when the maximum longitudinal acceleration of multiple 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 the second level; when the maximum longitudinal acceleration of multiple consecutive time periods is less than the second maximum acceleration threshold, the road adhesion level is the third level.

[0161] In a possible implementation, the control module 404 is configured to determine a corresponding road adhesion parameter according to the road adhesion level when the vehicle operating state is a target operating mode, wherein the road adhesion parameter is positively correlated with the road adhesion level, and the target operating mode includes: the driving state, the driving state, the braking state, and the unknown state;

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

[0163] The road adhesion identification device provided in this embodiment can execute the method provided in the above method embodiment, and its implementation principle and technical effect are similar, which will not be described in detail in this embodiment.

[0164] Figure 5 This is a schematic diagram of the structure of the electronic device provided in this application. Figure 5 As shown, the electronic device 50 provided in this embodiment includes: at least one processor 501 and a memory 502. Optionally, the device 50 also includes a communication component 503. The processor 501, the memory 502 and the communication component 503 are connected via a bus 504.

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

[0166] The specific implementation process of the processor 501 can be found in the above method embodiment, and its implementation principle and technical effect are similar, so this embodiment will not be repeated here.

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

[0168] The memory may include a high-speed memory (Random Access Memory, RAM), and may also include a non-volatile memory (NVM), such as at least one disk storage.

[0169] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or 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 ease of representation, the bus in the drawings of this application is not limited to only one bus or one type of bus.

[0170] The present application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0171] The present application also provides a computer-readable storage medium, in which computer-executable instructions are stored. When a processor executes the computer-executable instructions, the above method is implemented.

[0172] The above-mentioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, 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 memory, 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 a 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 a component of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (Application Specific Integrated Circuits, referred to as: ASIC). Of course, the processor and the readable storage medium can also exist in the device as discrete components.

[0174] The division of units is only a logical function division, and there may be other divisions in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

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

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

[0177] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0178] Those skilled in the art can understand that all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to program instructions. 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, disk or optical disk and other media that can store program codes.

[0179] Finally, it should be noted that those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses or adaptations of the present invention, which follow the general principles of the present invention and include common knowledge or customary technical means in the art not disclosed by the present invention, are not limited to the precise structure described above and shown in the drawings, and may be modified and changed in various ways without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A road surface adhesion recognition method, characterized in that: include: Determine the working state of the vehicle according to the state information of the vehicle during driving, wherein the working state of the vehicle is one of the following: driving state, braking state, driving state, anti-lock braking system ABS state, acceleration anti-skid system ASR state, unknown state; Acquire corresponding identification parameters according to the working state of the vehicle, the identification parameters of the driving state include: the slope of the fitted straight line between the total slip rate of each wheel on the vehicle and the longitudinal acceleration, the identification parameters of the braking state include: the ratio between the longitudinal acceleration and the total slip rate, the identification parameters of the driving state include: 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 slip rate of the wheels on the drive shaft, and the slip rate of the wheel is the proportion of the difference between the wheel speed and the vehicle speed in the vehicle speed; Matching the identification parameter corresponding to the vehicle working state with the corresponding parameter threshold to obtain the road adhesion level under the vehicle working state; A road adhesion parameter is determined according to the road adhesion level and the vehicle operating state.

2. The method according to claim 1, characterized in that The driving state satisfies the following conditions: the absolute value of the longitudinal acceleration is less than the first acceleration threshold, the absolute value of the total slip rate of each wheel on the vehicle is less than the first total slip rate threshold, the accelerator pedal opening is less than the first acceleration opening threshold, the brake pedal opening is less than the first brake opening threshold, the vehicle speed is greater than or equal to the first vehicle speed threshold, the absolute value of the drive shaft slip rate is less than the first drive slip rate threshold, and the absolute value of the steering wheel angle is less than the first angle threshold; The braking 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 driving state satisfies the following conditions: ASR is not activated, 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; The ABS state satisfies the following conditions: the ABS is activated, wherein 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 decompression state; The ASR state satisfies the following condition: the ASR activation signal indicates an activated state.

3. The method according to claim 2, characterized in that The matching of the identification parameter corresponding to the vehicle working state with the corresponding parameter threshold to obtain the road adhesion level under the vehicle working state includes: Construct one or more value ranges according to the parameter threshold corresponding to each of the vehicle operating states, and different value ranges correspond to different levels; The value range of the identification parameter is determined as a target value range, and the level corresponding to the target value range is used as the road surface adhesion level.

4. The method according to claim 3, characterized in that: In the driving state, the road adhesion level is positively correlated with the slope of the fitting straight line, and the slope of the fitting straight line is obtained by fitting with the total slip rate as the horizontal axis and the longitudinal acceleration as the vertical axis; In the braking state, the road surface 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 shaft 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 the time period, and the maximum longitudinal acceleration and the minimum longitudinal acceleration are equal in absolute value but opposite in sign; In the ASR state, the road adhesion level is positively correlated with the maximum longitudinal acceleration in the time period; In the unknown state, the road adhesion level identified last time is the road adhesion level identified this time.

5. The method according to claim 4, characterized in that When the slope of the fitted straight line is greater than or equal to a first slope threshold, the road surface adhesion level is the 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 surface adhesion level is the second level; when the slope of the fitted straight line is less than the second slope threshold, the road surface adhesion level is the third level; In the braking state, when a plurality of the ratios are continuously greater than or equal to a first ratio threshold, the road surface adhesion level is a first level; when a plurality of the ratios are continuously less than the first ratio threshold and greater than or equal to a second ratio threshold, the road surface adhesion level is a second level; and when the ratio is less than the second ratio threshold, the road surface adhesion level is a third level; In the driving state, when the longitudinal acceleration is greater than or equal to a fourth acceleration threshold value for multiple consecutive times, the road adhesion level is the first level; when the longitudinal acceleration is less than the fourth acceleration threshold value but greater than or equal to a fifth acceleration threshold value for multiple consecutive times, and the drive shaft slip rate is greater than or equal to a fourth drive slip rate threshold value for multiple consecutive times, the road adhesion level is the second level; otherwise, the road adhesion level is the third level; In the ABS state, when the maximum longitudinal deceleration corresponding to the minimum longitudinal acceleration of multiple consecutive time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion level is the first level; when the maximum longitudinal deceleration of multiple 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 the second level; when the maximum longitudinal deceleration of multiple consecutive 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 multiple consecutive time periods is greater than or equal to a first maximum acceleration threshold, the road adhesion level is the first level; when the maximum longitudinal acceleration of multiple 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 the second level; when the maximum longitudinal acceleration of multiple consecutive time periods is less than the second maximum acceleration threshold, the road adhesion level is the third level.

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

7. A road surface adhesion recognition device, characterized in that: include: An acquisition module is used to determine the working state of the vehicle according to the state information of the vehicle during driving, wherein the working state of the vehicle is one of the following: driving state, braking state, driving state, anti-lock braking system ABS state, acceleration anti-skid system ASR state, and unknown state; a first processing module, configured to obtain corresponding identification parameters according to the working state of the vehicle, wherein the identification parameters of the driving state include: the slope of a fitted straight line between the total slip rate of each wheel on the vehicle and the longitudinal acceleration, the identification parameters of the braking state include: the ratio between the longitudinal acceleration and the total slip rate, the identification parameters of the driving state include: 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 slip rate of the wheels on the drive shaft, and the wheel slip rate is the proportion of the difference between the wheel speed and the vehicle speed in the vehicle speed; A second processing module is used to match the identification parameter corresponding to the vehicle working state with the corresponding parameter threshold to obtain the road adhesion level under the vehicle working state; A control module is used to determine a road surface adhesion parameter according to the road surface adhesion level and the vehicle operating state.

8. An electronic device, characterized in that: include: A processor, and a memory communicatively connected to the processor; 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 6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 6 when executed by a processor.

10. A computer program product, characterized in that The invention comprises a computer program, which implements the method according to any one of claims 1 to 6 when being executed by a processor.

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