Method and apparatus for determining road friction coefficient, and device and readable storage medium

Abstract

A method and apparatus for determining a road friction coefficient, and a device and a readable storage medium. The method for determining a road friction coefficient comprises: acquiring first road friction coefficients which are uploaded by target vehicles traveling on the same road within a preset duration (S11); on the basis of the first road friction coefficients which are uploaded by the target vehicles, determining a second road friction coefficient of the road (S12); sending the second road friction coefficient to a subsequent vehicle on the road, such that the subsequent vehicle performs control on the basis of the second road friction coefficient (S13); and receiving a slip rate uploaded by the subsequent vehicle, and on the basis of the slip rate, updating the second road friction coefficient of the road (S14). By means of determining a second road friction coefficient of a road on the basis of first road friction coefficients uploaded by vehicles on the same road, and updating the second road friction coefficient of the road on the basis of a slip rate of a subsequent vehicle, the accuracy of determining a road friction coefficient is improved; and by means of providing the second road friction coefficient of the road to the subsequent vehicle, the subsequent vehicle learns the road friction coefficient in advance.

Description

Method, device, apparatus and readable storage medium for determining road adhesion coefficient

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application number 202410264316.5 filed on March 7, 2024, entitled “Method, device, apparatus and readable storage medium for determining road adhesion coefficient,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of vehicle information technology, and in particular to a method, device, equipment and readable storage medium for determining a road adhesion coefficient. Background Art

[0004] TRFE (Tire-Road Friction Estimation) is a research field in vehicle information technology, which can provide important road adhesion information for drivers and vehicle active control systems.

[0005] At present, the methods for estimating the road adhesion coefficient can generally be divided into two types: experimental-based and model-based. The experimental-based method is to install special sensors such as radar and optics on the vehicle, and pre-calibrate the correspondence between the special sensor parameters and the road adhesion coefficient. The road adhesion coefficient is then determined based on the current special sensor parameters and the pre-calibrated correspondence. The model-based method uses common on-board sensors such as speed sensors to obtain vehicle dynamic response signals related to the road adhesion coefficient in the vehicle, and estimates the road adhesion coefficient in combination with relevant models.

[0006] Of the two methods mentioned above, the experimental approach relies heavily on the reliability of specific sensors. When these sensors are unreliable, the resulting road adhesion coefficient becomes less accurate. Model-based methods, when the vehicle operates within the linear range, rely primarily on the tire's lateral and longitudinal forces, independent of the road's properties. Therefore, the road adhesion coefficient cannot be estimated in this case. Furthermore, in practice, when tire damage causes changes in vertical elastic stiffness, the estimated road adhesion coefficient can deviate significantly. Furthermore, these two methods cannot estimate the subsequent road adhesion coefficient in advance, thus shortening the driver's reaction time.

[0007] In summary, how to improve the accuracy of determining the road adhesion coefficient and predict the road adhesion coefficient in advance is a technical problem that currently needs to be solved urgently by those skilled in the art.

[0008] Summary of the Invention

[0009] In view of the above problems, the present application provides a method, device, equipment and readable storage medium for determining a road adhesion coefficient, which are used to improve the accuracy of determining the road adhesion coefficient and predict the road adhesion coefficient in advance.

[0010] In a first aspect, the present application provides a method for determining a road surface adhesion coefficient, comprising: obtaining a first road surface adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period; determining a second road surface adhesion coefficient of the road based on the first road surface adhesion coefficient of the road uploaded by each target vehicle; sending the second road surface adhesion coefficient to subsequent vehicles on the road, so that the subsequent vehicles are controlled according to the second road surface adhesion coefficient; receiving a slip rate uploaded by the subsequent vehicles, and updating the second road surface adhesion coefficient of the road according to the slip rate.

[0011] The above-mentioned technical solution disclosed in the embodiment of the present application improves the accuracy of the road adhesion coefficient determination by determining the second road adhesion coefficient of the road based on the first road adhesion coefficient uploaded by each target vehicle traveling on the same road within a preset time period and iteratively updating the second road adhesion coefficient of the road based on the slip rate uploaded by subsequent vehicles on the road. The determined second road adhesion coefficient of the road is provided to subsequent vehicles on the road for use, so that the subsequent vehicles can obtain the road adhesion coefficient of the road in advance, thereby improving the vehicle driving experience and safety.

[0012] In some embodiments, before updating the second road adhesion coefficient of the road according to the slip rate, the method further includes: receiving the first road adhesion coefficient uploaded by the subsequent vehicle;

[0013] The second road adhesion coefficient of the road is updated according to the slip rate, including: if the slip rates of at least N of the subsequent vehicles are less than a first preset slip rate, the second road adhesion coefficient of the road is increased; N is greater than or equal to 2; if the slip rates of at least N of the subsequent vehicles are not less than the first preset slip rate and less than a second preset slip rate, the second road adhesion coefficient of the road is maintained; the second preset slip rate is greater than the first preset slip rate; if the slip rates of at least N of the subsequent vehicles are not less than the second preset slip rate, the second road adhesion coefficient of the road is updated according to the first road adhesion coefficient of the road uploaded by the first preset number of the subsequent vehicles most recently received.

[0014] Through the above process, the second road surface adhesion coefficient of the determined road is verified using the slip rate of the subsequent vehicle on the road, and the second road surface adhesion coefficient of the road is updated based on the verification result to improve the accuracy of the determination of the second road surface adhesion coefficient of the road.

[0015] In some embodiments, it also includes: if the slip rate of a single subsequent vehicle is not less than the second preset slip rate, determining the single subsequent vehicle as a target subsequent vehicle, and notifying the target subsequent vehicle to control according to the first road surface adhesion coefficient of the road obtained by itself; when the slip rate of the target subsequent vehicle is not less than the second preset slip rate, if the slip rate of the vehicle behind the target subsequent vehicle is less than the second preset slip rate, determining that there is a health problem with the tires of the target subsequent vehicle, and sending a reminder to replace the tires to the target subsequent vehicle; when the slip rate of the target subsequent vehicle is not less than the second preset slip rate, if the slip rate of a predetermined number or a predetermined proportion of vehicles behind the target subsequent vehicle is not less than the second preset slip rate, executing the step of updating the second road surface adhesion coefficient of the road according to the first road surface adhesion coefficients of the road uploaded by the most recently received first preset number of subsequent vehicles, determining that the road surface of the road has changed, and issuing a notification of the road surface change.

[0016] Through the above, if only a single vehicle experiences wheel slippage, it can be determined that there is a health problem with the vehicle's tire, and the driver can be reminded to replace the tire in time to reduce the occurrence of tire blowout accidents. If multiple vehicles experience wheel slippage, it can be determined that the road surface has changed. At this time, not only the second road adhesion coefficient of the road is updated for subsequent vehicles to verify, but also a notification of the road surface change is issued to allow subsequent vehicles to be informed of the relevant situation in advance and take measures in advance to improve driving safety.

[0017] In some embodiments, the method further includes: obtaining location information, road surface type, and weather conditions of the road; and determining a third road surface adhesion coefficient of the road based on the location information, road surface type, and weather conditions of the road.

[0018] The second road surface adhesion coefficient of the road is determined based on the first road surface adhesion coefficient of the road uploaded by each target vehicle, including: averaging the first road surface adhesion coefficient of the road uploaded by each target vehicle to obtain a first average value of the first road surface adhesion coefficient; and determining the smallest of the first average value of the first road surface adhesion coefficient and the third road surface adhesion coefficient as the second road surface adhesion coefficient of the road.

[0019] A more accurate second road adhesion coefficient is obtained by simultaneously using the vehicle itself as a sensor to detect and obtain the first road adhesion coefficient and the third road adhesion coefficient estimated based on the road surface type and weather conditions to participate in the determination of the second road adhesion coefficient.

[0020] In some embodiments, the second road adhesion coefficient of the road is updated based on the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles that have been received the most recently, including: averaging the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles that have been received the most recently, to obtain a second average value of the first road adhesion coefficient; and determining the minimum of the second average value of the first road adhesion coefficient and the third road adhesion coefficient that has been obtained the most recently as the second road adhesion coefficient of the road.

[0021] The second road adhesion coefficient of the road is reduced by averaging the first road adhesion coefficients of the road uploaded by the first preset number of subsequent vehicles, and the smallest of the average calculation result and the third road adhesion coefficient newly obtained is determined as the second road adhesion coefficient of the road, thereby improving the accuracy of updating the second road adhesion coefficient of the road.

[0022] In some embodiments, the second road adhesion coefficient of the road is determined based on the first road adhesion coefficient of the road uploaded by each of the target vehicles, including: averaging the first road adhesion coefficients of the road uploaded by each of the target vehicles to obtain a third average value of the first road adhesion coefficient; and determining the smallest of the third average value of the first road adhesion coefficient and a preset road adhesion coefficient as the second road adhesion coefficient of the road.

[0023] By implementing the above, the second road surface adhesion coefficient of the road is determined based on the first road surface adhesion coefficients detected by multiple vehicles, thereby improving the accuracy of determining the second road surface adhesion coefficient of the road.

[0024] In some embodiments, updating the second road surface adhesion coefficient of the road according to the first road surface adhesion coefficients of the road uploaded by the first preset number of subsequent vehicles that have been received most recently includes:

[0025] performing an averaging operation on the first road surface adhesion coefficients of the road uploaded by a first preset number of the subsequent vehicles to obtain a fourth average value of the first road surface adhesion coefficients;

[0026] The smallest one of the fourth average value of the first road surface adhesion coefficient and the preset road surface adhesion coefficient is determined as the second road surface adhesion coefficient of the road.

[0027] The second road surface adhesion coefficient of the road is re-determined based on the first road surface adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles, so as to improve the accuracy of determining the second road surface adhesion coefficient of the road.

[0028] In some embodiments, before determining the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each target vehicle, the method further includes: obtaining a slip rate uploaded by each target vehicle, and eliminating the first road adhesion coefficient of the road uploaded by a target vehicle whose slip rate is not within a preset slip rate range;

[0029] And / or, the first road surface adhesion coefficients of the roads uploaded by the target vehicles that meet a preset data removal rule are eliminated.

[0030] Through the above two processes, the abnormal first road adhesion coefficient is first removed, and then the second road adhesion coefficient of the road is determined according to the first road adhesion coefficients uploaded by the remaining target vehicles, so as to improve the accuracy of the determination of the second road adhesion coefficient of the road.

[0031] In some embodiments, the preset data removal rule includes removing maximum and minimum values, or removing data whose deviation from the mean exceeds a preset threshold.

[0032] Abnormal data is removed by removing the maximum and minimum values ​​of the first road adhesion coefficients, or removing the first road adhesion coefficients whose deviation from the mean exceeds a preset threshold, thereby facilitating improving the accuracy of determining the second road adhesion coefficient of the road.

[0033] In some embodiments, the method further includes: storing the position information of the road, the second road adhesion coefficient of the road, and the time of determining the second road adhesion coefficient in a road adhesion coefficient map.

[0034] By saving the road's location information, the road's second road adhesion coefficient, and the time when the road's second road adhesion coefficient is determined in a road adhesion coefficient map, subsequent queries can facilitate the acquisition of the road's second road adhesion coefficient at a certain time or times, and can facilitate the acquisition of changes in the road's second road adhesion coefficient over time.

[0035] In some embodiments, obtaining the first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period includes: obtaining the first road adhesion coefficient uploaded by each vehicle and the time when each vehicle uploaded the first road adhesion coefficient, and obtaining the position information of each vehicle in real time; obtaining the first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within the preset time period based on the position information of each vehicle, the time when each vehicle uploaded the first road adhesion coefficient, and the first road adhesion coefficient uploaded by each vehicle.

[0036] By improving the reliability and accuracy of obtaining the first road surface adhesion coefficient of the road as described above, the accuracy of determining the second road surface adhesion coefficient of the road is improved.

[0037] In some embodiments, it also includes: if the slip rate uploaded by the subsequent vehicle is not received within a preset time threshold, obtaining the first road adhesion coefficient of the road uploaded by a second preset number of target vehicles that have recently traveled on the road, and returning to execute the step of determining the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each of the target vehicles.

[0038] If the cloud server does not receive the slip rate uploaded by subsequent vehicles within a preset time threshold, the current round of iteration for updating the second road surface adhesion coefficient of the road is terminated and a new round of iteration is started, thereby improving the accuracy of determining the second road surface adhesion coefficient of the road.

[0039] In the second aspect, the present application provides a road adhesion coefficient determination device, including: an acquisition module for acquiring a first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period; a first determination module for determining a second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each target vehicle; a sending module for sending the second road adhesion coefficient to subsequent vehicles on the road, so that the subsequent vehicles are controlled according to the second road adhesion coefficient; an updating module for receiving the slip rate uploaded by the subsequent vehicles, and updating the second road adhesion coefficient of the road according to the slip rate.

[0040] In a third aspect, the present application provides a road adhesion coefficient determination device, comprising: a memory for storing a computer program; and a processor for implementing the steps of the road adhesion coefficient determination method as described in any one of the above items when executing the computer program.

[0041] In a fourth aspect, the present application provides a readable storage medium, in which a computer program is stored. When the computer program is executed by a processor, the steps of the method for determining the road adhesion coefficient as described in any one of the above items are implemented.

[0042] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0044] FIG1 is a flow chart of a method for determining a road adhesion coefficient according to some embodiments of the present application;

[0045] FIG2 is a flowchart of controlling according to the slip ratio of a subsequent vehicle according to some embodiments of the present application;

[0046] FIG3 is a flow chart of a method for determining a road adhesion coefficient according to some embodiments of the present application;

[0047] FIG4 is a flow chart of updating a second road surface adhesion coefficient of a road in some embodiments of the present application;

[0048] FIG5 is a flowchart of updating a second road surface adhesion coefficient of a road in some embodiments of the present application;

[0049] FIG6 is a flowchart of determining a second road surface adhesion coefficient of a road in some embodiments of the present application;

[0050] FIG7 is a schematic structural diagram of a device for determining a road adhesion coefficient according to some embodiments of the present application;

[0051] FIG8 is a schematic structural diagram of a road adhesion coefficient determination device according to some embodiments of the present application. DETAILED DESCRIPTION

[0052] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0054] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0055] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0056] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0057] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0058] TRFE is a widely studied area of ​​vehicle information technology. It provides crucial road adhesion information to drivers (both human and machine) and active vehicle control systems. If drivers can keep abreast of changes in road adhesion information, they can proactively adopt appropriate driving strategies to ensure adequate safety margins. For example, when cornering on slippery roads, the vehicle speed should be kept lower than on high-adhesion surfaces. For the ACC (Adaptive Cruise Control) system, if the road adhesion coefficient is low, the safe distance from the vehicle ahead should be increased appropriately. In the vehicle's Electronic Stability Control (ESC) system, the control algorithm adjusts the desired values ​​of control targets such as yaw angle and slip angular velocity based on the estimated road adhesion coefficient. Furthermore, the road adhesion coefficient is also a crucial piece of road surface information in intelligent transportation systems.

[0059] At present, the road adhesion coefficient estimation methods can generally be divided into two types: experimental-based and model-based. The experimental-based method is to install special sensors such as radar and optics on the vehicle, and pre-calibrate the correspondence between the special sensor parameters and the road adhesion coefficient. The road adhesion coefficient is then determined based on the current special sensor parameters and the correspondence between the pre-calibrated special sensor parameters and the road adhesion coefficient. The model-based method uses common on-board sensors such as vehicle speed sensors to obtain vehicle dynamic response signals related to the road adhesion coefficient in the vehicle, and estimates the road adhesion coefficient in combination with relevant models.

[0060] Of the two methods mentioned above, the experimental approach relies heavily on the reliability of specific sensors. When this reliability decreases, the resulting road adhesion coefficient becomes less accurate. Furthermore, the model-based approach, for typical sensors used in control systems to improve vehicle stability, cannot determine the road adhesion coefficient as long as the vehicle operates within the linear range. Within this range, the lateral and longitudinal forces exerted by the tires are primarily determined by their elastic properties and are independent of road surface characteristics. Furthermore, in actual use, when tire damage causes changes in vertical elastic stiffness, the results of existing estimation methods often deviate significantly, converging to erroneous values. Furthermore, traditional methods cannot estimate the subsequent road adhesion coefficient in advance, significantly shortening the driver's reaction time.

[0061] To this end, the applicant has proposed a method, device, equipment and readable storage medium for determining a road surface adhesion coefficient. The method improves the accuracy of determining the second road surface adhesion coefficient of a road by determining the second road surface adhesion coefficient of the road based on the first road surface adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period, and updating the second road surface adhesion coefficient of the road based on the slip rate uploaded by subsequent vehicles on the road. The method also improves the accuracy of determining the second road surface adhesion coefficient of the road by providing the second road surface adhesion coefficient of the road determined each time to subsequent vehicles on the road for use, so that subsequent vehicles can obtain the road surface adhesion coefficient of the road in advance, thereby facilitating extending the driver's reaction time and improving the driving experience and safety of the vehicle.

[0062] 1 , which is a flow chart of a method for determining a road adhesion coefficient according to some embodiments of the present application, may include the following steps:

[0063] S11: Obtaining a first road adhesion coefficient uploaded by each target vehicle traveling on the same road within a preset time period.

[0064] It should be noted that the execution entity of the road adhesion coefficient determination method provided in the embodiment of the present application can be a road adhesion coefficient determination device, and the road adhesion coefficient determination device can specifically be a cloud server, a notebook, a tablet computer, etc. The embodiment of the present application is explained using the execution entity as a cloud server as an example.

[0065] When determining the road adhesion coefficient, a cloud server can obtain location information for each road, and each vehicle can transmit its location information to the cloud server in real time. This allows the cloud server to identify target vehicles traveling on the same road based on this information. A target vehicle is defined as a vehicle traveling on the same road. Furthermore, each vehicle traveling on the same road can be used as a sensor to detect and obtain a first road adhesion coefficient for the road, and the detected first road adhesion coefficient can be promptly transmitted to the cloud server. The vehicle can determine the first road adhesion coefficient based on drive wheel torque, lateral and longitudinal acceleration, yaw angular velocity, and wheel slip rate; braking force, driving force, or road support force; or using specialized sensors, modeling methods, or other methods.

[0066] Based on the above, the cloud server can determine the target vehicles traveling on the same road. Furthermore, considering that the road adhesion coefficient varies with road conditions (e.g., dryness, wetness), vehicle speed, etc., to improve the accuracy of the road adhesion coefficient determination, the cloud server can obtain the first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period. The preset time period can be set in advance through experiments or experience, such as 10 minutes, 30 minutes, etc., and the number of target vehicles traveling on the same road within the preset time period can be greater than or equal to 1.

[0067] S12: Determine a second road surface adhesion coefficient of the road according to the first road surface adhesion coefficient of the road uploaded by each target vehicle.

[0068] On the basis of step S11, the cloud server may determine the second road adhesion coefficient of the corresponding road according to the first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period.

[0069] When a plurality of target vehicles travel on the road within a preset time period, the accuracy of determining the second road surface adhesion coefficient of the road can be improved through the above process.

[0070] S13: Sending the second road adhesion coefficient to subsequent vehicles on the road, so that the subsequent vehicles are controlled according to the second road adhesion coefficient.

[0071] After determining the second road adhesion coefficient for a road, the cloud server can transmit this information to subsequent vehicles on the road. Subsequent vehicles on the road are vehicles that subsequently travel on the road. Upon receiving the second road adhesion coefficient from the cloud server, subsequent vehicles on the road can use this information to control wheel torque, thereby improving driving experience and safety.

[0072] By determining the second road adhesion coefficient of the road and sending the determined second road adhesion coefficient of the road to subsequent vehicles on the road, subsequent vehicles on the road can know the road adhesion coefficient of the road in advance, thereby improving vehicle driving safety and driver experience.

[0073] S14: receiving the slip rate uploaded by the subsequent vehicle, and updating the second road surface adhesion coefficient of the road according to the slip rate.

[0074] When a subsequent vehicle on the road is controlling its vehicle according to the second road adhesion coefficient, it can monitor the slip rate of its own wheel in real time and transmit the monitored slip rate to the cloud server. The slip rate can be specifically determined by vehicle speed and wheel speed. After receiving the slip rate uploaded by the subsequent vehicle on the road, the cloud server can update the second road adhesion coefficient based on the slip rate of the subsequent vehicle to obtain an updated second road adhesion coefficient for the road. The cloud server can then return to steps S13 and S14, transmitting the updated second road adhesion coefficient to the subsequent vehicle on the road, causing the subsequent vehicle to control its vehicle according to the received second road adhesion coefficient. The cloud server also receives the slip rate uploaded by the subsequent vehicle and updates the second road adhesion coefficient based on the slip rate of the subsequent vehicle. This process is then repeated repeatedly, i.e., continuously updating the second road adhesion coefficient based on the slip rate of the subsequent vehicle on the road (the slip rate being the slip rate obtained after the subsequent vehicle controls its vehicle according to the pre-updated second road adhesion coefficient). This allows for iterative updates of the second road adhesion coefficient, thereby improving the accuracy of determining the second road adhesion coefficient.

[0075] The above-mentioned technical solution disclosed in the embodiment of the present application improves the accuracy of the road adhesion coefficient determination by determining the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period, and iteratively updating the second road adhesion coefficient of the road based on the slip rate uploaded by subsequent vehicles on the road. The determined second road adhesion coefficient of the road is provided to subsequent vehicles on the road for use, so that the subsequent vehicles can obtain the road adhesion coefficient of the road in advance, thereby improving the vehicle driving experience and safety.

[0076] According to some embodiments of the present application, before updating the second road surface adhesion coefficient of the road according to the slip rate, the following steps may also be included:

[0077] receiving a first road adhesion coefficient uploaded by a subsequent vehicle;

[0078] Updating the second road adhesion coefficient of the road according to the slip rate may include:

[0079] If the slip ratios of at least N following vehicles are less than a first predetermined slip ratio, increasing a second road surface adhesion coefficient of the road; N is greater than or equal to 2;

[0080] If the slip ratio of at least N following vehicles is not less than a first preset slip ratio and less than a second preset slip ratio, maintaining the second road surface adhesion coefficient of the road; the second preset slip ratio is greater than the first preset slip ratio;

[0081] If the slip ratios of at least N subsequent vehicles are not less than the second preset slip ratio, the second road surface adhesion coefficient of the road is updated according to the first road surface adhesion coefficients of the road uploaded by the first preset number of subsequent vehicles most recently received.

[0082] In an embodiment of the present application, before updating the second road adhesion coefficient of the road according to the slip rate, the cloud server may also receive the first road adhesion coefficient of the road obtained by the subsequent vehicle itself as a sensor detection and uploaded by the subsequent vehicle. Specifically, the cloud server may upload itself as the first road adhesion coefficient of the road obtained by the sensor detection while uploading the slip rate, so that the first road adhesion coefficient uploaded by the subsequent vehicle can participate in the update of the second road adhesion coefficient of the road, thereby improving the accuracy of the determination of the second road adhesion coefficient of the road.

[0083] When the second road surface adhesion coefficient of the road is updated according to the slip rate of the following vehicle on the road, the following strategy may be used to update the second road surface adhesion coefficient of the road:

[0084] (1) If at least N (N is an integer greater than or equal to 2, such as 2 or 3) subsequent vehicles have slip rates less than the first preset slip rate, it indicates that the second road adhesion coefficient of the determined road is a safe value, that is, it indicates that the second road adhesion coefficient of the determined road is too small. In this case, the second road adhesion coefficient of the road can be increased so that the subsequent vehicles can fully utilize the road adhesion coefficient, thereby ensuring the safety of the subsequent vehicles. The first preset slip rate can be determined based on a slip rate threshold. For example, the slip rate threshold can be any value within the range of 15%-20%. The first preset slip rate can specifically be 0.8*the first slip rate threshold. Of course, the first preset slip rate can also be the product of other ratios and the slip rate threshold.

[0085] When increasing the second road adhesion coefficient, a fixed value can be added to the second road adhesion coefficient to update the second road adhesion coefficient. Specifically, the second road adhesion coefficient can be updated using TRFE2 = TRFE2 + α, where TRFE2 before the equal sign is the updated second road adhesion coefficient, TRFE2 after the equal sign is the pre-updated second road adhesion coefficient, and α is a fixed value. It should be noted that the value of α can vary depending on the road surface type (specifically, the corresponding α for each road surface type can be pre-calibrated). Of course, α can also be a uniform value.

[0086] In the above process, a judgment can be made based on the order in which subsequent vehicles enter the road. Taking N=2 as an example, if the slip ratio of the first subsequent vehicle is less than the first preset slip ratio, the condition of the above update strategy is not met. In this case, the first subsequent vehicle continues to be controlled according to the road's second road adhesion coefficient before the update (i.e., the road's current second road adhesion coefficient), and the above update strategy is not executed. If the slip ratio of the second subsequent vehicle is not less than the first preset slip ratio, the condition of the above update strategy is not met. In this case, the second subsequent vehicle continues to be controlled according to the road's second road adhesion coefficient before the update (i.e., the road's current second road adhesion coefficient), and the above update strategy is not executed. If the slip ratio of the second subsequent vehicle is less than the first preset slip ratio, the condition of the above update strategy is met. In this case, the above update strategy can be executed, i.e., the road's second road adhesion coefficient can be increased, and the updated second road adhesion coefficient of the road can be sent to subsequent vehicles traveling on the road (i.e., subsequent vehicles on the road), so that subsequent vehicles on the road are controlled according to the updated second road adhesion coefficient of the road.

[0087] (2) If the slip ratios of at least N following vehicles are not less than the first preset slip ratio and less than the second preset slip ratio, then the second road adhesion coefficient of the determined road is a warning value, that is, the second road adhesion coefficient of the determined road is relatively appropriate. In this case, the second road adhesion coefficient of the road can be kept unchanged, that is, TRFE2 can be iterated at the original value. The second preset slip ratio is greater than the first preset slip ratio. The second preset slip ratio can also be determined based on a slip ratio threshold. For example, the second preset slip ratio can be specifically 0.95*slip ratio threshold. Of course, the second preset slip ratio can also be the product of other ratios and the slip ratio threshold.

[0088] It should be noted that, in the above process, the condition judgment may also be performed according to the order in which subsequent vehicles enter the road, and the specific process will not be repeated here.

[0089] (3) If the slip ratios of at least N subsequent vehicles are not less than the second preset slip ratio, it indicates that the second road adhesion coefficient of the determined road is a dangerous value, that is, it indicates that the second road adhesion coefficient of the determined road is too large. Specifically, it may be that the road surface condition of the road has changed significantly (for example, the road has become relatively wet, etc.), resulting in the excessive slip ratio of the subsequent vehicles. At this time, the second road adhesion coefficient of the road can be updated based on the first road adhesion coefficients of the road uploaded by the first preset number of subsequent vehicles most recently received, so as to re-determine the second road adhesion coefficient of the road based on the first road adhesion coefficients of the road uploaded by the first preset number of subsequent vehicles most recently traveling on the road, thereby reducing the second road adhesion coefficient of the road and improving the accuracy of determining the second road adhesion coefficient of the road. The size of the first preset number can be set in advance based on experience, etc., and the above process can ensure that sufficiently new and sufficient first road adhesion coefficients are involved in updating the second road adhesion coefficient of the road, so as to improve the accuracy of determining the second road adhesion coefficient of the road.

[0090] In addition, when the slip rates of at least N following vehicles are not less than the second preset slip rate, if these vehicles are still traveling on the aforementioned road, they can be controlled using the first road adhesion coefficient obtained by themselves.

[0091] It should be noted that, in the above process, the condition judgment can also be performed according to the order in which subsequent vehicles enter the road, and the specific process will not be repeated here.

[0092] The at least N subsequent vehicles in the three update strategies described above may specifically be at least N discontinuous subsequent vehicles. As long as the slip ratios of at least N subsequent vehicles appear in chronological order to meet the conditions corresponding to any of the three update strategies described above, the second road surface adhesion coefficient of the road is updated according to the update method of the corresponding update strategy. Alternatively, the at least N subsequent vehicles in the three update strategies described above may be at least N consecutive subsequent vehicles.

[0093] After the cloud server updates the second road surface adhesion coefficient of the road according to the above-mentioned update strategy, it can send the updated second road surface adhesion coefficient of the road to subsequent vehicles on the road, so that the subsequent vehicles are controlled according to the updated second road surface adhesion coefficient of the road. The cloud server can also receive the slip rate uploaded by the subsequent vehicles after they are controlled according to the updated second road surface adhesion coefficient of the road, and update the second road surface adhesion coefficient of the road according to the slip rate uploaded by the subsequent vehicles. The cloud server can cycle in this way to iteratively update the second road surface adhesion coefficient of the road, thereby improving the accuracy of determining the second road surface adhesion coefficient of the road.

[0094] Through the above process, the second road surface adhesion coefficient of the determined road is verified using the slip rate of the subsequent vehicle on the road, and the second road surface adhesion coefficient of the road is updated based on the verification result to improve the accuracy of the determination of the second road surface adhesion coefficient of the road.

[0095] According to some embodiments of the present application, see FIG2 , which is a flow chart of controlling according to the slip rate of the following vehicle in some embodiments of the present application. The road adhesion coefficient determination method may further include:

[0096] If the slip ratio of the single following vehicle is not less than the second preset slip ratio, the single following vehicle is determined as a target following vehicle, and the target following vehicle is notified to perform control according to the first road surface adhesion coefficient obtained by the target following vehicle;

[0097] When the slip ratio of the target following vehicle is not less than a second preset slip ratio, if the slip ratio of the vehicle behind the target following vehicle is less than the second preset slip ratio, determining that there is a health problem with the tire of the target following vehicle, and sending a reminder to the target following vehicle to replace the tire;

[0098] When the slip rate of the target subsequent vehicle is not less than the second preset slip rate, if the slip rates of a predetermined number or a predetermined proportion of vehicles behind the target subsequent vehicle are not less than the second preset slip rate, a step of updating the second road surface adhesion coefficient of the road based on the first road surface adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles most recently received is executed, and a change in the road surface of the road is determined, and a notification of the change in the road surface is issued.

[0099] In an embodiment of the present application, when the second road adhesion coefficient of the road is updated based on the slip rate uploaded by subsequent vehicles on the road, if the slip rate of a single subsequent vehicle is not less than the second preset slip rate, the single subsequent vehicle can be determined as the target subsequent vehicle, and the target subsequent vehicle can be notified to control according to the first road adhesion coefficient of the road obtained by itself to limit the torque output or reduce the braking force, so as to improve the driving safety of the target subsequent vehicle.

[0100] On the basis that the slip rate of the target subsequent vehicle is not less than the second preset slip rate, if the slip rate of the vehicle behind the target subsequent vehicle is less than the second preset slip rate (specifically, the slip rate of a predetermined number or a predetermined proportion of vehicles behind the target subsequent vehicle is less than the second preset slip rate, the predetermined number or the predetermined proportion can be set in advance, and the predetermined number can be greater than 1), it can be determined that the tires of the target subsequent vehicle itself have health problems (such as wear, aging, etc.) and cause its slip rate to be too large. At this time, a reminder to replace the tire can be sent to the target subsequent vehicle through the on-board display screen or head-up display system of the target subsequent vehicle, so that the driver in the target subsequent vehicle can be informed of the reminder in time, thereby facilitating timely replacement of the tires, etc., so that the target subsequent vehicle will not have the problem of tire blowout, reduce the occurrence of driving hazards, and improve vehicle driving safety. That is, through the above process, the known second road adhesion coefficient of the road can be used to judge the health status of the tire based on the verification of the slip rate of a specific vehicle. Specifically, when a specific vehicle uses the second road adhesion coefficient of the determined road to control the wheel torque and a large wheel slip occurs, while other vehicles are normal, it can be determined that the decrease in the single vehicle friction coefficient is due to severe wheel wear. At this time, the driver can be reminded to replace the tire in time.

[0101] On the basis that the slip rate of the target subsequent vehicle is not less than the second preset slip rate, if the slip rates of at least a predetermined number or a predetermined proportion of vehicles behind the target subsequent vehicle are not less than the second preset slip rate, it is determined that the problem is not with the target subsequent vehicle itself, but rather that the road surface has changed. Therefore, not only can the step of updating the second road surface adhesion coefficient of the road according to the first road surface adhesion coefficient of the road uploaded by the most recently received first preset number of subsequent vehicles be performed to achieve the update of the second road surface adhesion coefficient of the road, so that the subsequent vehicles on the road are controlled according to the updated second road surface adhesion coefficient of the road, but also a notification of the change in the road surface can be issued through broadcasting or the like, so that the vehicles that are about to travel on the road can be prepared in advance, thereby ensuring the vehicle driving experience and safety.

[0102] Through the above, if only a single vehicle experiences wheel slippage, it can be determined that there is a health problem with the vehicle's tire, and the driver can be reminded to replace the tire in time to reduce the occurrence of tire blowout accidents. If multiple vehicles experience wheel slippage, it can be determined that the road surface has changed. At this time, not only the second road adhesion coefficient of the road is updated for subsequent vehicles to verify, but also a notification of the road surface change is issued to allow subsequent vehicles to be informed of the relevant situation in advance and take measures in advance to improve driving safety.

[0103] According to some embodiments of the present application, see FIG3 , which is a flow chart of a method for determining a road adhesion coefficient in some embodiments of the present application. FIG3 illustrates an example in which n target vehicles on the same road upload a first road adhesion coefficient for the road within a preset time period, and each of the n target vehicles determines the first road adhesion coefficient for the road based on drive wheel torque, lateral and longitudinal acceleration, yaw angular velocity, and wheel slip rate. The method for determining a road adhesion coefficient may further include:

[0104] Obtaining location information, road surface type, and weather conditions of the road, and determining a third road surface adhesion coefficient of the road based on the location information, road surface type, and weather conditions of the road;

[0105] Determining the second road surface adhesion coefficient of the road based on the first road surface adhesion coefficient of the road uploaded by each target vehicle may include:

[0106] Performing an average calculation on the first road surface adhesion coefficients of the roads uploaded by each target vehicle to obtain a first average value of the first road surface adhesion coefficients;

[0107] The smallest of the first average value of the first road surface adhesion coefficient and the third road surface adhesion coefficient is determined as the second road surface adhesion coefficient of the road.

[0108] In the embodiment of the present application, the cloud server can also obtain the road's location information, road surface type, and weather conditions. The road surface type refers to the road's pavement material, such as concrete pavement, asphalt pavement, etc., and the weather conditions can be sunny, rainy, snowy, etc. Considering that weather conditions may change, the cloud server can obtain the road's location information, road surface type, and weather conditions in real time or at regular intervals to improve the accuracy of determining the second road surface adhesion coefficient.

[0109] After obtaining the road's location information, road surface type, and weather conditions, the cloud server can determine the third road surface adhesion coefficient based on the road's location information, road surface type, and weather conditions. Specifically, a correspondence table or a correspondence model between the road's location information, road surface type, and weather conditions, and the third road surface adhesion coefficient can be pre-stored in the cloud server. Then, after obtaining the road's location information, road surface type, and weather conditions, the third road surface adhesion coefficient can be determined based on the correspondence table or the correspondence model.

[0110] Based on the above, the cloud server can determine the second road adhesion coefficient for the road based on the first road adhesion coefficients uploaded by each target vehicle traveling on the same road within a preset time period, and the third road adhesion coefficient for the road determined by the cloud server at the corresponding time based on the road's location information, road type, and weather conditions. The second road adhesion coefficient for the road can be determined based on the latest third road adhesion coefficient and the current first road adhesion coefficients. It should be noted that if the time each target vehicle uploads its first road adhesion coefficient and the time it obtains the third road adhesion coefficient are the same, the third road adhesion coefficient and the first road adhesion coefficient for the same time are obtained. If the time each target vehicle uploads its first road adhesion coefficient and the time it obtains the third road adhesion coefficient are different, the first road adhesion coefficients within the latest preset time period from the time the third road adhesion coefficient was obtained are obtained to contribute to the determination of the second road adhesion coefficient for the road. By simultaneously using the first road adhesion coefficient detected by the vehicle itself as a sensor and the third road adhesion coefficient estimated by the cloud server to determine the second road adhesion coefficient for the road, a more accurate second road adhesion coefficient can be obtained.

[0111] Specifically, the above process may be as follows: averaging the first road adhesion coefficients of the road uploaded by each target vehicle to obtain a first average value of the first road adhesion coefficient; then, obtaining the minimum value from the first average value of the first road adhesion coefficient and the third road adhesion coefficient; and determining the obtained minimum value as the second road adhesion coefficient of the road. This allows the second road adhesion coefficient of the determined road to be instantly lowered by taking the minimum value if conditions such as rain occur that reduce the road adhesion coefficient, thereby improving the timeliness and accuracy of determining the second road adhesion coefficient of the road.

[0112] According to some embodiments of the present application, referring to FIG4 , which is a flow chart of updating a second road surface adhesion coefficient of a road in some embodiments of the present application, the second road surface adhesion coefficient of the road is updated based on the first preset number of first road surface adhesion coefficients received, including:

[0113] Performing an average calculation on the first road adhesion coefficients of the roads uploaded by a first preset number of subsequent vehicles to obtain a second average value of the first road adhesion coefficients;

[0114] The smallest of the second average value of the first road surface adhesion coefficient and the most recently acquired third road surface adhesion coefficient is determined as the second road surface adhesion coefficient of the road.

[0115] In the case where the cloud server determines the third road adhesion coefficient of the road based on the location information, road surface type and weather conditions of the road, when the second road adhesion coefficient of the road is updated based on the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles, the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles can be averaged to obtain a second average value of the first road adhesion coefficient. Then, the minimum one is obtained from the second average value of the first road adhesion coefficient and the third road adhesion coefficient obtained most recently, and the obtained minimum one is determined as the second road adhesion coefficient of the road, so as to reduce the second road adhesion coefficient of the road and improve the accuracy of the update of the second road adhesion coefficient of the road. Among them, before averaging the first road surface adhesion coefficients of the road uploaded by the first preset number of subsequent vehicles that have been received recently, the first road surface adhesion coefficients of the road uploaded by subsequent vehicles whose slip rates are not within the preset slip rate range can be eliminated, and / or the first road surface adhesion coefficients that meet the preset data removal rules can be eliminated. The preset slip rate range can be specifically 15%-20%, and the preset data removal rules can specifically be removing the maximum and minimum values ​​or removing data whose deviation from the mean exceeds a preset threshold, so as to remove abnormal first road surface adhesion coefficients, thereby improving the accuracy of updating the second road surface adhesion coefficient of the road.

[0116] According to some embodiments of the present application, determining a second road surface adhesion coefficient of a road based on a first road surface adhesion coefficient of the road uploaded by each target vehicle may include:

[0117] Performing an average calculation on the first road surface adhesion coefficients of the roads uploaded by each target vehicle to obtain a third average value of the first road surface adhesion coefficients;

[0118] The smallest of the third average value of the first road surface adhesion coefficient and the preset road surface adhesion coefficient is determined as the second road surface adhesion coefficient of the road.

[0119] If the cloud server has not determined the third road adhesion coefficient based on the road's location information, road surface type, and weather conditions, a preset road adhesion coefficient can be set for the road based on the road surface type through testing, calibration, or experience. This preset road adhesion coefficient can be the road adhesion coefficient for scenarios such as rainy days. The process of determining the second road adhesion coefficient based on the first road adhesion coefficient uploaded by each target vehicle can specifically include averaging the first road adhesion coefficients uploaded by each target vehicle to obtain a third average first road adhesion coefficient. The minimum of the third average first road adhesion coefficient and the preset road adhesion coefficient is then determined as the second road adhesion coefficient. This allows the second road adhesion coefficient to be determined based on the first road adhesion coefficients detected by multiple vehicles, thereby improving the accuracy of determining the second road adhesion coefficient.

[0120] Of course, the third average value of the first road adhesion coefficient obtained by averaging the first road adhesion coefficients uploaded by each target vehicle may also be determined as the second road adhesion coefficient of the road to improve the accuracy of determining the second road adhesion coefficient of the road.

[0121] According to some embodiments of the present application, referring to FIG5 , which is a flow chart of updating a second road surface adhesion coefficient of a road in some embodiments of the present application, the second road surface adhesion coefficient of the road is updated based on the first preset number of first road surface adhesion coefficients received, including:

[0122] performing an averaging operation on the first road surface adhesion coefficients of the roads uploaded by a first preset number of subsequent vehicles to obtain a fourth average value of the first road surface adhesion coefficients;

[0123] The smallest of the fourth average value of the first road surface adhesion coefficient and the preset road surface adhesion coefficient is determined as the second road surface adhesion coefficient of the road.

[0124] When the cloud server has not determined the third road adhesion coefficient of the road based on the location information, road surface type and weather conditions of the road, the specific process of updating the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles that have been received the most recently can be to average the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles that have been received the most recently to obtain a fourth average value of the first road adhesion coefficient, and then select the smallest one from the fourth average value of the first road adhesion coefficient and the preset road adhesion coefficient, and determine the selected smallest one as the second road adhesion coefficient of the road, so as to redetermine the second road adhesion coefficient of the road, thereby achieving an update of the second road adhesion coefficient of the road and improving the accuracy of determining the second road adhesion coefficient of the road. Among them, before averaging the first preset number of first road surface adhesion coefficients received most recently, the first road surface adhesion coefficients uploaded by subsequent vehicles whose slip rates are not within the preset slip rate range can be eliminated, and / or the first road surface adhesion coefficients that meet the preset data removal rules can be eliminated. The preset slip rate range can be specifically 15%-20%, and the preset data removal rules can specifically be removing the maximum and minimum values ​​or removing data whose deviation from the mean exceeds a preset threshold, so as to remove abnormal first road surface adhesion coefficients, thereby improving the accuracy of updating the second road surface adhesion coefficient of the road.

[0125] According to some embodiments of the present application, see FIG6 , which is a flow chart of determining a second road adhesion coefficient for some embodiments of the present application. FIG6 illustrates an example of road 1 and n target vehicles uploading the first road adhesion coefficient of road 1 to a cloud server within a preset time period. Before determining the second road adhesion coefficient of the road based on the first road adhesion coefficient uploaded by each target vehicle, the following steps may also be included:

[0126] Obtaining the slip ratio uploaded by each target vehicle, and eliminating the first road surface adhesion coefficient of the road uploaded by the target vehicle whose slip ratio is not within the preset slip ratio range;

[0127] And / or, the first road surface adhesion coefficients of the roads uploaded by each target vehicle that meet a preset data removal rule are eliminated.

[0128] In addition to uploading the first road adhesion coefficient detected by the target vehicle's sensor to the cloud server, the target vehicle may also upload its own slip ratio to the cloud server. Specifically, the target vehicle may upload its own slip ratio simultaneously with the first road adhesion coefficient. The slip ratio can be determined based on vehicle speed and wheel speed. Accordingly, before determining the second road adhesion coefficient based on the first road adhesion coefficient uploaded by each target vehicle, the cloud server may obtain the slip ratios uploaded by each target vehicle within a preset time period. The cloud server may then exclude first road adhesion coefficients uploaded by target vehicles whose slip ratios are not within the preset slip ratio range. This eliminates inaccurate first road adhesion coefficient measurements based on the target vehicle's own driving conditions. This allows only target vehicles with optimal braking performance and maximum first road adhesion coefficients to participate in the determination of the second road adhesion coefficient, thereby improving the accuracy of the determination. The preset slip ratio range may be 15%-20%, although other ranges may be set as needed.

[0129] And / or, when processing the first road adhesion coefficients of the roads uploaded by each target vehicle, the cloud server can eliminate the first road adhesion coefficients of the roads uploaded by each target vehicle that meet the preset data removal rules. For example, the maximum and minimum values ​​of the first road adhesion coefficients uploaded by each target vehicle within a preset time period can be removed to remove abnormal first road adhesion coefficients, reduce errors, and thus improve the accuracy of determining the second road adhesion coefficient of the road.

[0130] Through the above two processes, the abnormal first road adhesion coefficient is first removed, and then the second road adhesion coefficient of the road is determined according to the first road adhesion coefficients uploaded by the remaining target vehicles, so as to improve the accuracy of the determination of the second road adhesion coefficient of the road.

[0131] According to some embodiments of the present application, the preset data removal rule includes removing the maximum value and the minimum value, or removing data whose deviation from the mean value exceeds a preset threshold.

[0132] The preset data removal rules mentioned above may include removing maximum and minimum values, or removing data whose deviation from the mean exceeds a preset threshold. The preset threshold may be 3 times the standard deviation. Of course, the size of the preset threshold may also be adjusted as needed.

[0133] Abnormal data in the first road surface adhesion coefficients uploaded by each vehicle is removed by removing the maximum first road surface adhesion coefficient and the minimum first road surface adhesion coefficient from the first road surface adhesion coefficients uploaded by each vehicle, or by removing the first road surface adhesion coefficients whose deviation from the mean of the first road surface adhesion coefficients exceeds a preset threshold from the first road surface adhesion coefficients uploaded by each vehicle, thereby facilitating improving the accuracy of determining the second road surface adhesion coefficient of the road.

[0134] According to some embodiments of the present application, the method may further include:

[0135] The position information of the road, the second road surface adhesion coefficient of the road, and the time of determining the second road surface adhesion coefficient are stored in a road surface adhesion coefficient map.

[0136] In an embodiment of the present application, the location information of a road can be obtained and stored in a road adhesion coefficient map. Furthermore, each time a road's second road adhesion coefficient is determined (including the initial determination and each subsequent update iteration), the determined second road adhesion coefficient and the time of determination can be stored in the corresponding road adhesion coefficient map. That is, the road adhesion coefficient map can include the location information of the road, the second road adhesion coefficient of the road, and the time of determination of the second road adhesion coefficient of the road, so that the second road adhesion coefficient of the road at a specific time or times can be subsequently queried and obtained, and the change in the second road adhesion coefficient of the road over time can be easily obtained.

[0137] According to some embodiments of the present application, obtaining a first road surface adhesion coefficient of a road uploaded by each target vehicle traveling on the same road within a preset time period may include:

[0138] Obtain the first road adhesion coefficient uploaded by each vehicle and obtain the position information of each vehicle in real time;

[0139] The first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period is obtained according to the position information of each vehicle and the first road adhesion coefficient uploaded by each vehicle.

[0140] In an embodiment of the present application, the process of obtaining the first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period can be specifically as follows: first, the first road adhesion coefficient uploaded by each vehicle is obtained, and the position information of each vehicle and the current time information corresponding to the position information of each vehicle are obtained in real time, and the position information of each road can also be obtained in advance; then, the target vehicles traveling on the same road within the preset time period can be determined based on the position information of each vehicle obtained in real time, the current time information corresponding to the position information of each vehicle, and the position information of each road obtained in advance, and the first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within the preset time period can be obtained from the first road adhesion coefficients uploaded by each vehicle based on the time when each vehicle uploads the first road adhesion coefficient, so as to improve the reliability and accuracy of obtaining the first road adhesion coefficient of the road, thereby improving the accuracy of determining the second road adhesion coefficient of the road.

[0141] Of course, it is also possible to first identify the time when each vehicle traveling on the same road enters the road and the time when it leaves the road through image detection or other methods, and determine the target vehicles traveling on the same road within a preset time period based on the time when each vehicle enters the road and the time when it leaves the road, and obtain the first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within the preset time period.

[0142] According to some embodiments of the present application, the method may further include:

[0143] If the slip rate uploaded by the subsequent vehicle is not received within the preset time threshold, the first road adhesion coefficient of the road uploaded by the second preset number of target vehicles traveling on the road is obtained, and the process returns to the step of determining the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each target vehicle.

[0144] In an embodiment of the present application, if the cloud server does not receive the slip rate uploaded by a subsequent vehicle for a period exceeding a preset time threshold (the specific duration can be set as needed, such as several hours), it can be determined that no vehicles have traveled on the corresponding road for a relatively long period of time. Therefore, the current iteration of updating the second road adhesion coefficient of the road can be terminated, and the first road adhesion coefficients of the road uploaded by a second preset number of target vehicles most recently traveling on the road can be obtained. The second preset number can be set in advance based on experience. Thereafter, the process can return to the step of determining the second road adhesion coefficient of the road based on the first road adhesion coefficients uploaded by each target vehicle, i.e., the process can return to step S12 and begin a new iteration, thereby improving the accuracy of determining the second road adhesion coefficient of the road.

[0145] The present application also provides a road adhesion coefficient determination device. Referring to FIG7 , which is a schematic structural diagram of a road adhesion coefficient determination device according to some embodiments of the present application, the road adhesion coefficient determination device 70 may include: an acquisition module 71, a first determination module 72, a sending module 73, and an updating module 74. The acquisition module 71 is configured to acquire a first road adhesion coefficient for a road uploaded by each target vehicle traveling on the same road for a preset duration; the first determination module 72 is configured to determine a second road adhesion coefficient for the road based on the first road adhesion coefficient uploaded by each target vehicle; the sending module 73 is configured to send the second road adhesion coefficient to subsequent vehicles on the road, so that the subsequent vehicles are controlled according to the second road adhesion coefficient; and the updating module 74 is configured to receive a slip rate uploaded by the subsequent vehicle and update the second road adhesion coefficient for the road based on the slip rate.

[0146] According to some embodiments of the present application, the road surface adhesion coefficient determining device 70 may further include a receiving module for receiving a first road surface adhesion coefficient uploaded by a subsequent vehicle before updating the second road surface adhesion coefficient of the road according to the slip rate;

[0147] The updating module 74 updates the second road adhesion coefficient of the road according to the slip rate, and is specifically used to increase the second road adhesion coefficient of the road if the slip rates of at least N subsequent vehicles are less than a first preset slip rate; N is greater than or equal to 2; if the slip rates of at least N subsequent vehicles are not less than the first preset slip rate and less than the second preset slip rate, maintain the second road adhesion coefficient of the road; the second preset slip rate is greater than the first preset slip rate; if the slip rates of at least N subsequent vehicles are not less than the second preset slip rate, update the second road adhesion coefficient of the road according to the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles most recently received.

[0148] According to some embodiments of the present application, the update module 74 is also used to determine a single subsequent vehicle as a target subsequent vehicle if the slip rate of a single subsequent vehicle is not less than a second preset slip rate, and notify the target subsequent vehicle to control according to the first road surface adhesion coefficient of the road obtained by itself; when the slip rate of the target subsequent vehicle is not less than the second preset slip rate, if the slip rate of the vehicle behind the target subsequent vehicle is less than the second preset slip rate, it is determined that there is a health problem with the tire of the target subsequent vehicle, and a reminder to replace the tire is sent to the target subsequent vehicle; when the slip rate of the target subsequent vehicle is not less than the second preset slip rate, if the slip rate of a predetermined number or a predetermined proportion of vehicles behind the target subsequent vehicle is not less than the second preset slip rate, then execute the step of updating the second road surface adhesion coefficient of the road according to the first road surface adhesion coefficient of the road uploaded by the most recently received first preset number of subsequent vehicles, determine that the road surface of the road has changed, and issue a notification of the change in the road surface.

[0149] According to some embodiments of the present application, the road adhesion coefficient determining device 70 may further include a second determining module for obtaining location information, road surface type, and weather conditions of the road, and determining a third road adhesion coefficient of the road based on the location information, road surface type, and weather conditions of the road;

[0150] The first determination module 72 determines the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each target vehicle, and is specifically used to average the first road adhesion coefficients of the road uploaded by each target vehicle to obtain a first average value of the first road adhesion coefficient; and determine the smallest of the first average value of the first road adhesion coefficient and the third road adhesion coefficient as the second road adhesion coefficient of the road.

[0151] According to some embodiments of the present application, the update module 74 updates the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles that have been most recently received, and is specifically used to average the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles that have been most recently received to obtain the second average value of the first road adhesion coefficient; and determine the minimum of the second average value of the first road adhesion coefficient and the third road adhesion coefficient that has been most recently obtained as the second road adhesion coefficient of the road.

[0152] According to some embodiments of the present application, the first determination module 72 determines the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each target vehicle, and is specifically used to average the first road adhesion coefficient of the road uploaded by each target vehicle to obtain a third average value of the first road adhesion coefficient; and determines the minimum of the third average value of the first road adhesion coefficient and the preset road adhesion coefficient as the second road adhesion coefficient of the road.

[0153] According to some embodiments of the present application, the update module 74 updates the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles that have been most recently received, and is specifically used to average the first road adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles that have been most recently received to obtain a fourth average value of the first road adhesion coefficient; and determine the minimum of the fourth average value of the first road adhesion coefficient and the preset road adhesion coefficient as the second road adhesion coefficient of the road.

[0154] According to some embodiments of the present application, the road adhesion coefficient determination device 70 may further include a elimination module for obtaining the slip rate uploaded by each target vehicle before determining the second road adhesion coefficient of the road based on the first road adhesion coefficient uploaded by each target vehicle, and eliminating the first road adhesion coefficient of the road uploaded by the target vehicle whose slip rate is not within the preset slip rate range; and / or, eliminating the first road adhesion coefficient of the road uploaded by each target vehicle that meets the preset data removal rule.

[0155] According to some embodiments of the present application, the preset data removal rules may include removing maximum and minimum values, or removing data whose deviation from the mean exceeds a preset threshold.

[0156] According to some embodiments of the present application, the road adhesion coefficient determining device 70 may further include a storage module for storing the position information of the road, the second road adhesion coefficient of the road, and the time of determining the second road adhesion coefficient in a road adhesion coefficient map.

[0157] According to some embodiments of the present application, the acquisition module 71 acquires the first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period, specifically used to acquire the first road adhesion coefficient uploaded by each vehicle and acquire the position information of each vehicle in real time; based on the position information of each vehicle and the first road adhesion coefficient uploaded by each vehicle, the first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period is acquired.

[0158] According to some embodiments of the present application, the road adhesion coefficient determination device 70 may further include an execution module for obtaining the first road adhesion coefficient of the road uploaded by a second preset number of target vehicles most recently traveling on the road if the slip rate uploaded by a subsequent vehicle is not received within a preset time threshold, and returning to execute the step of determining the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each target vehicle.

[0159] The present application also provides a road adhesion coefficient determination device. Referring to FIG8 , which is a schematic structural diagram of a road adhesion coefficient determination device according to some embodiments of the present application, the road adhesion coefficient determination device may include:

[0160] Memory 81, for storing computer programs;

[0161] The processor 82, when used to execute the computer program stored in the memory 81, can implement the following steps:

[0162] The method comprises obtaining a first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period; determining a second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each target vehicle; sending the second road adhesion coefficient to subsequent vehicles on the road so that the subsequent vehicles are controlled according to the second road adhesion coefficient; receiving a slip rate uploaded by the subsequent vehicle, and updating the second road adhesion coefficient of the road based on the slip rate.

[0163] The present application also provides a readable storage medium, wherein the readable storage medium stores a computer program, and when the computer program is executed by a processor, the following steps can be implemented:

[0164] The method comprises obtaining a first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period; determining a second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each target vehicle; sending the second road adhesion coefficient to subsequent vehicles on the road so that the subsequent vehicles are controlled according to the second road adhesion coefficient; receiving a slip rate uploaded by the subsequent vehicle, and updating the second road adhesion coefficient of the road based on the slip rate.

[0165] For the description of the relevant parts of the road adhesion coefficient determination device, equipment and readable storage medium provided in the embodiments of the present application, please refer to the detailed description of the corresponding parts of the road adhesion coefficient determination method provided in the embodiments of the present application, and will not be repeated here.

[0166] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A method for determining a road adhesion coefficient, characterized in that: include: Obtaining a first road surface adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period; Determining a second road surface adhesion coefficient of the road according to the first road surface adhesion coefficient of the road uploaded by each target vehicle; sending the second road adhesion coefficient to a subsequent vehicle on the road, so that the subsequent vehicle is controlled according to the second road adhesion coefficient; Receive the slip rate uploaded by the subsequent vehicle, and update the second road surface adhesion coefficient of the road according to the slip rate.

2. The method for determining the road adhesion coefficient according to claim 1, characterized in that: Before updating the second road adhesion coefficient of the road according to the slip rate, the method further includes: receiving a first road adhesion coefficient uploaded by the subsequent vehicle; Updating a second road surface adhesion coefficient of the road according to the slip rate includes: If the slip ratios of at least N of the following vehicles are less than a first preset slip ratio, increasing a second road surface adhesion coefficient of the road; N is greater than or equal to 2; If the slip ratios of at least N of the following vehicles are not less than the first preset slip ratio and less than a second preset slip ratio, maintaining the second road surface adhesion coefficient of the road; the second preset slip ratio is greater than the first preset slip ratio; If the slip ratios of at least N of the following vehicles are not less than the second preset slip ratio, the second road surface adhesion coefficient of the road is updated according to the first road surface adhesion coefficients of the road uploaded by the first preset number of the following vehicles most recently received.

3. The method for determining the road adhesion coefficient according to claim 2, characterized in that: Also includes: If the slip ratio of a single following vehicle is not less than the second preset slip ratio, the single following vehicle is determined as a target following vehicle, and the target following vehicle is notified to perform control according to the first road surface adhesion coefficient obtained by the target following vehicle; When the slip ratio of the target following vehicle is not less than the second preset slip ratio, if the slip ratio of the vehicle behind the target following vehicle is less than the second preset slip ratio, determining that there is a health problem with the tire of the target following vehicle, and sending a reminder to the target following vehicle to replace the tire; When the slip rate of the target subsequent vehicle is not less than the second preset slip rate, if the slip rates of a predetermined number or a predetermined proportion of vehicles behind the target subsequent vehicle are not less than the second preset slip rate, the step of updating the second road surface adhesion coefficient of the road based on the first road surface adhesion coefficient of the road uploaded by the first preset number of subsequent vehicles that have been received most recently is executed, and it is determined that the road surface of the road has changed, and a notification of the change in the road surface is issued.

4. The method for determining the road adhesion coefficient according to claim 2, wherein: Also includes: obtaining location information, road surface type, and weather conditions of the road, and determining a third road surface adhesion coefficient of the road based on the location information, road surface type, and weather conditions of the road; Determining a second road surface adhesion coefficient of the road according to the first road surface adhesion coefficient of the road uploaded by each target vehicle includes: performing an average calculation on the first road surface adhesion coefficients of the road uploaded by each target vehicle to obtain a first average value of the first road surface adhesion coefficients; The smallest of the first average value of the first road surface adhesion coefficient and the third road surface adhesion coefficient is determined as the second road surface adhesion coefficient of the road.

5. The method for determining the road adhesion coefficient according to claim 4, characterized in that: Updating the second road surface adhesion coefficient of the road according to the first road surface adhesion coefficients of the road uploaded by the first preset number of subsequent vehicles that have been received most recently, including: performing an averaging operation on the first road surface adhesion coefficients of the road uploaded by a first preset number of the subsequent vehicles to obtain a second average value of the first road surface adhesion coefficients; The smallest of the second average value of the first road surface adhesion coefficient and the third road surface adhesion coefficient obtained most recently is determined as the second road surface adhesion coefficient of the road.

6. The method for determining the road adhesion coefficient according to claim 2, characterized in that: Determining a second road surface adhesion coefficient of the road according to the first road surface adhesion coefficient of the road uploaded by each target vehicle includes: performing an average calculation on the first road surface adhesion coefficients of the road uploaded by each of the target vehicles to obtain a third average value of the first road surface adhesion coefficients; The smallest one of the third average value of the first road surface adhesion coefficient and a preset road surface adhesion coefficient is determined as the second road surface adhesion coefficient of the road.

7. The method for determining the road adhesion coefficient according to claim 6, characterized in that: Updating the second road surface adhesion coefficient of the road according to the first road surface adhesion coefficients of the road uploaded by the first preset number of subsequent vehicles that have been received most recently, including: performing an averaging operation on the first road surface adhesion coefficients of the road uploaded by a first preset number of the subsequent vehicles to obtain a fourth average value of the first road surface adhesion coefficients; The smallest one of the fourth average value of the first road surface adhesion coefficient and the preset road surface adhesion coefficient is determined as the second road surface adhesion coefficient of the road.

8. The method for determining the road adhesion coefficient according to any one of claims 1 to 7, characterized in that: Before determining the second road surface adhesion coefficient of the road according to the first road surface adhesion coefficient of the road uploaded by each target vehicle, the method further includes: Obtaining the slip rate uploaded by each target vehicle, and eliminating the first road adhesion coefficient of the road uploaded by the target vehicle whose slip rate is not within the preset slip rate range; And / or, the first road surface adhesion coefficients of the roads uploaded by the target vehicles that meet a preset data removal rule are eliminated.

9. The method for determining the road adhesion coefficient according to claim 8, characterized in that: The preset data removal rule includes removing the maximum value and the minimum value, or removing data whose deviation from the mean value exceeds a preset threshold.

10. The method for determining the road adhesion coefficient according to any one of claims 1 to 9, characterized in that: Also includes: The position information of the road, the second road surface adhesion coefficient of the road, and the time of determining the second road surface adhesion coefficient are stored in a road surface adhesion coefficient map.

11. The method for determining the road adhesion coefficient according to any one of claims 1 to 9, characterized in that: Obtaining a first road surface adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period, including: Obtaining the first road adhesion coefficient uploaded by each vehicle and the time when each vehicle uploaded the first road adhesion coefficient, and obtaining the position information of each vehicle in real time; The first road adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within the preset time period is obtained based on the position information of each vehicle, the time when each vehicle uploaded the first road adhesion coefficient, and the first road adhesion coefficient uploaded by each vehicle.

12. The method for determining the road adhesion coefficient according to any one of claims 1 to 9, characterized in that: Also includes: If the slip rate uploaded by the subsequent vehicle is not received within the preset time threshold, the first road adhesion coefficient of the road uploaded by the second preset number of target vehicles that have traveled on the road is obtained, and the process returns to the step of determining the second road adhesion coefficient of the road based on the first road adhesion coefficient of the road uploaded by each of the target vehicles.

13. A device for determining a road adhesion coefficient, characterized in that: include: An acquisition module, configured to acquire a first road surface adhesion coefficient of the road uploaded by each target vehicle traveling on the same road within a preset time period; a first determining module, configured to determine a second road surface adhesion coefficient of the road according to the first road surface adhesion coefficient of the road uploaded by each target vehicle; a sending module, configured to send the second road adhesion coefficient to a subsequent vehicle on the road, so that the subsequent vehicle is controlled according to the second road adhesion coefficient; An updating module is configured to receive the slip rate uploaded by the subsequent vehicle and update the second road surface adhesion coefficient of the road according to the slip rate.

14. A device for determining a road adhesion coefficient, characterized in that: include: Memory for storing computer programs; A processor, configured to implement the steps of the method for determining a road adhesion coefficient as claimed in any one of claims 1 to 12 when executing the computer program.

15. A readable storage medium, characterized in that The readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method for determining the road adhesion coefficient according to any one of claims 1 to 12 are implemented.

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