A recommended speed determination method, apparatus and device

Abstract

The application provides a recommended speed determination method, device and equipment, and relates to the technical field of vehicle-road cooperation, and the recommended speed determination method comprises the following steps: acquiring map information of a target area and historical traffic information in the target area; the historical traffic information comprises trajectory points of vehicles, historical speeds of the vehicles at each trajectory point and geographical positions where traffic accidents of the vehicles occur; according to the historical traffic information, historical average speeds of the vehicles at target positions and traffic accident frequencies are counted; the target positions are determined according to the map information, the trajectory points of the vehicles and the geographical positions where the traffic accidents of the vehicles occur; a risk model is established according to the historical average speeds of the vehicles at the target positions and the traffic accident frequencies; and recommended speeds of different trajectory points in the target area are obtained according to the risk model and the historical speeds of each trajectory point. According to the application, fine-grained recommended speeds can be obtained, and driving safety is considered while driving efficiency is taken into account.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of vehicle-road cooperation technology, and in particular to a recommended speed determination method, device and equipment. BACKGROUND

[0002] A road system is often a complex system, and the ideal speed at different positions is often affected by traffic pressure, road conditions, visibility, etc.

[0003] The speed control judgment basis of automatic driving or assisted driving often has a wide range. There are generally three kinds of existing schemes for dynamically determining driving speed: one is based on vision, obtaining control speed and control distance from surrounding vehicles; the second is based on roadside perception, obtaining current speed or predicted speed from traffic information; the third is based on floating cars, obtaining current speed or predicted speed.

[0004] In the prior art, according to the existing implementation path, the trajectory planning module of the vehicle calculates the speed change cost according to the current speed and the recommended speed (the recommended speed can be determined according to the speed of the surrounding vehicles or the historical speed), and then calculates the appropriate control conditions, but the existing implementation path has the following disadvantages: (1) the recommended speed can be the maximum historical speed, but this case often contains dangerous behavior, and in actual situations, due to traffic pressure and specific road conditions, drivers are prone to accelerate and sudden braking, etc., so the historical speed often contains these dangerous driving behaviors; (2) the recommended speed is the speed limit value, but the speed limit value is too coarse, and in individual road sections, the actual driving speed is often lower than the speed limit, affecting driving efficiency; (3) the recommended speed can be the middle value of the historical speed or the 75th percentile value of the historical speed, which will also make the autonomous vehicle appear more conservative driving behavior.

[0005] In summary, the existing scheme for determining driving speed has a coarse driving speed granularity, and has the problem of being unable to balance driving safety and driving efficiency. SUMMARY

[0006] The embodiments of the present application provide a recommended speed determination method, device and equipment to solve the problem of coarse driving speed granularity in the prior art, which cannot balance driving safety and driving efficiency.

[0007] In order to solve the above technical problems, the embodiments of the present application provide the following technical solutions:

[0008] The embodiments of the present application provide a recommended speed determination method, comprising:

[0009] obtain map information of a target area and historical traffic information in the target area; the historical traffic information includes trajectory points of vehicles, historical speeds of vehicles at each trajectory point, and geographical positions of traffic accidents of vehicles;

[0010] According to the historical traffic information, a historical average speed of the vehicle at a target position and a number of traffic accidents are counted, wherein the target position is determined according to the map information, the trajectory points of the vehicle and geographical positions where the vehicle has traffic accidents;

[0011] According to the historical average speed of the vehicle at the target position and the number of traffic accidents, a risk model is established, wherein the risk model is used to represent a corresponding relationship between the number of traffic accidents and the historical average speed of the vehicle in the target region;

[0012] According to the risk model and the historical speed of each trajectory point, a recommended speed of different trajectory points in the target region is obtained.

[0013] Optionally, the counting of the historical average speed of the vehicle at the target position and the number of traffic accidents according to the historical traffic information comprises:

[0014] According to road nodes in the map information, first position encodings corresponding to the road nodes are obtained by using a preset geographical encoding mechanism;

[0015] According to the trajectory points of the vehicle and the historical speed of the vehicle at each trajectory point, second position encodings corresponding to the trajectory points of the vehicle and historical speeds corresponding to each second position encoding are obtained by using the preset geographical encoding mechanism;

[0016] According to the geographical positions where the vehicle has traffic accidents, third position encodings corresponding to the geographical positions where the vehicle has traffic accidents and numbers of traffic accidents corresponding to each third position encoding are obtained by using the preset geographical encoding mechanism;

[0017] The position encodings that coincide in the first position encodings, the second position encodings and the third position encodings are taken as geographical encodings of the target position;

[0018] According to the historical speed corresponding to each second position encoding and the number of traffic accidents corresponding to each third position encoding, the historical average speed of the vehicle at the target position and the number of traffic accidents are obtained.

[0019] Optionally, the preset geographical encoding mechanism is a geographical hash encoding mechanism.

[0020] Optionally, the establishment of the risk model according to the historical average speed of the vehicle at the target position and the number of traffic accidents comprises:

[0021] The risk model is established by taking the number of traffic accidents of the vehicle at the target position as the dependent variable and the historical average speed of the vehicle at the target position as the independent variable, wherein the number of traffic accidents of the vehicle at the target position is a linear function of the historical average speed of the vehicle at the target position.

[0022] Optionally, the recommended speed of each trajectory point in the target region is obtained according to the risk model and the historical speed of each trajectory point, comprising:

[0023] The slope value of the linear function in the risk model is obtained.

[0024] For a target trajectory point, a plurality of historical speeds of the target trajectory point are obtained, and a recommended speed of the target trajectory point is determined according to the slope value and the plurality of historical speeds of the target trajectory point; the recommended speed of the target trajectory point is between the upper and lower limits of the plurality of historical speeds of the target trajectory point, and the recommended speed of the target trajectory point is negatively correlated with the slope value.

[0025] The target trajectory point is any one of the different trajectory points in the target region.

[0026] Optionally, the recommended speed of the target trajectory point is determined according to the slope value and the plurality of historical speeds of the target trajectory point, comprising:

[0027] The N historical speeds of the target trajectory point are sorted in descending order.

[0028] In a case where K is greater than a first preset threshold and less than a second preset threshold, the Mth historical speed is selected as the recommended speed of the target trajectory point.

[0029] M is equal to N multiplied by K and rounded down; K is equal to 1 minus the slope value.

[0030] The first preset threshold is less than the second preset threshold.

[0031] Optionally, the recommended speed of the target trajectory point is determined according to the slope value and the plurality of historical speeds of the target trajectory point, comprising:

[0032] The N historical speeds of the target trajectory point are sorted in descending order.

[0033] In a case where K is less than or equal to a first preset threshold, the Pth historical speed is selected as the recommended speed of the target trajectory point; P is equal to N multiplied by the first preset threshold and rounded down.

[0034] Optionally, the determining the recommended speed of the target trajectory point according to the slope value and the plurality of historical speeds of the target trajectory point comprises:

[0035] sorting the N historical speeds of the target trajectory point in descending order;

[0036] in a case that K is greater than or equal to a second preset threshold, selecting the Qth historical speed as the recommended speed of the target trajectory point; Q is equal to N multiplied by the second preset threshold and rounded down.

[0037] Optionally, the method further comprises:

[0038] adding the recommended speeds of different trajectory points in the target area to the map information of the target area.

[0039] Optionally, the method further comprises:

[0040] sending the recommended speeds of different trajectory points in the target area to the target vehicle before the target vehicle enters the target area; the target vehicle is configured to determine a final driving speed of the vehicle according to the recommended speed and first information;

[0041] wherein the first information comprises at least one of:

[0042] the speed of the preceding vehicle, the current speed of the target vehicle and the road speed limit.

[0043] Optionally, the method further comprises:

[0044] receiving recommended speed request information sent by the target vehicle;

[0045] sending the recommended speeds of different trajectory points in the target area to the target vehicle according to the recommended speed request information; the target vehicle is configured to determine a final driving speed of the vehicle according to the recommended speed and first information;

[0046] wherein the first information comprises at least one of:

[0047] the speed of the preceding vehicle, the current speed of the target vehicle and the road speed limit.

[0048] Embodiments of the present application also provide a recommended speed determination device, comprising:

[0049] an information acquisition module configured to acquire map information of a target area and historical traffic information in the target area; the historical traffic information comprises trajectory points of vehicles, historical speeds of vehicles at each trajectory point and geographical positions of traffic accidents of vehicles;

[0050] The information statistics module is configured to statistically determine a historical average speed of a vehicle at a target position and a number of traffic accidents according to the map information and the historical traffic information, wherein the target position is determined according to the map information, a trajectory point of the vehicle, and a geographical position where the vehicle has a traffic accident.

[0051] The model establishing module is configured to establish a risk model according to the historical average speed of the vehicle at the target position and the number of traffic accidents, wherein the risk model is used to represent a corresponding relationship between a number of traffic accidents and a historical average speed of a vehicle in the target region.

[0052] The first processing module is configured to obtain a recommended speed of different trajectory points in the target region according to the risk model and the historical speed of each trajectory point.

[0053] The embodiment of the present application further provides a recommended speed determination device, which comprises a processor, a memory, and a program stored in the memory and executable on the processor, and the program is used to implement the steps of the recommended speed determination method according to any one of the above.

[0054] The embodiment of the present application further provides a readable storage medium, wherein the readable storage medium stores a program, and the program is used to implement the steps of the recommended speed determination method according to any one of the above when the program is executed by a processor.

[0055] The present application has the following advantages:

[0056] According to the present application, the map information of a target region and historical traffic information in the target region are obtained, the historical average speed of a vehicle at a target position in the target region and the number of traffic accidents are statistically determined according to the map information and the historical traffic information, the risk model is established according to the historical average speed of the vehicle at the target position and the number of traffic accidents, and the recommended speed of different trajectory points in the target region is obtained according to the risk model and the historical speed of each trajectory point, so that the recommended speed with fine granularity can be obtained, and the driving safety is considered while the driving efficiency is taken into account. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 A flow chart of a recommended speed determination method provided by the embodiment of the present application is shown in the figure.

[0058] Figure 2 A structure schematic diagram of a vehicle-road cooperative system provided by the embodiment of the present application is shown in the figure.

[0059] Figure 3 A schematic diagram of a road node of a target region provided by the embodiment of the present application is shown in the figure.

[0060] Figure 4This is a schematic diagram of the structure of the vehicle provided in an embodiment of the present invention;

[0061] Figure 5 This is a schematic diagram of the recommended speed determination device provided in an embodiment of the present invention;

[0062] Figure 6 This is a schematic diagram illustrating the structure of the recommended speed determination device provided in an embodiment of the present invention. Detailed Implementation

[0063] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0064] This invention addresses the problem that existing technologies, which recommend driving speeds with coarse granularity, cannot simultaneously ensure driving safety and efficiency. It provides a method, apparatus, and device for determining recommended speeds.

[0065] like Figure 1 As shown, an embodiment of the present invention provides a method for determining a recommended speed, including:

[0066] Step 101: Obtain map information of the target area and historical traffic information within the target area; the historical traffic information includes vehicle trajectory points, historical speed of the vehicle at each trajectory point, and geographical location of the vehicle traffic accident.

[0067] It should be noted that the embodiments of the present invention provide a vehicle-road cooperative system, such as... Figure 2 As shown, the vehicle-road cooperative system includes roadside-deployed terminal equipment (such as roadside units (RSUs)), vehicle speed sensing equipment (such as laser radar (LIDAR) or cameras), onboard units (OBUs) installed in conventional vehicles, and vehicle-to-everything (V2X) data servers (also known as cloud devices or cloud servers) deployed in the cloud. The OBUs can be installed at the front or rear of the vehicle.

[0068] The recommended speed determination method provided in this embodiment of the invention is executed by a cloud device.

[0069] In this step, the historical traffic information can be collected by the roadside sensing device RSU or the on-board unit OBU. For example, the trajectory points of the vehicle and the geographical positions where the vehicle has traffic accidents in the historical traffic information are collected by the roadside sensing device RSU, and the historical speed of the vehicle at each trajectory point in the historical traffic information is collected by the on-board unit OBU. The historical traffic information collected by the RSU can be transmitted to the cloud device through a multi-access edge computing (MEC) private line. The historical traffic information collected by the RSU with uu interface capability can also be uploaded to the cloud device through the uu interface. The OBU collected historical traffic information can be uploaded to the cloud device through the RSU or the uu interface. The cloud device deploys a data storage service, i.e., stores the historical traffic information, and is also used for data mining services and data distribution services. Specifically, the data distribution can be performed by the cloud device to the MEC, and then distributed to the vehicle through the RSU. The data distribution can also be distributed by the OBU actively accessing the server. Please refer to Figure 2 The vehicle also has an autonomous driving module or an auxiliary driving module deployed thereon, which is used to receive the distributed data.

[0070] Preferably, the geographical positions where the vehicle has traffic accidents in the historical traffic information stored by the cloud device can be the geographical positions where the vehicle has traffic accidents more than 1 year away from the current time. The trajectory points of the vehicle and the historical speed of the vehicle at each trajectory point in the historical traffic information can be the trajectory points of the vehicle and the historical speed of the vehicle at each trajectory point within 1 week, 2 weeks, 1 month or 2 months away from the current time.

[0071] After the cloud device stores the geographical positions where the vehicle has traffic accidents more than 1 year away from the current time and the trajectory points of the vehicle and the historical speed of the vehicle at each trajectory point within 1 week, 2 weeks, 1 month or 2 months away from the current time, the learning and calculation of the recommended speed can be performed according to the following steps.

[0072] Step 102: According to the historical traffic information, the historical average speed of the vehicle at the target position and the number of traffic accidents are counted; the target position is determined according to the map information, the trajectory points of the vehicle and the geographical positions where the vehicle has traffic accidents.

[0073] In this step, the cloud device first determines the target position in the target area according to the map information, the trajectory points of the vehicle and the geographical positions where the vehicle has traffic accidents. Then, according to the historical speed of the vehicle at each trajectory point and the geographical positions where the vehicle has traffic accidents in the historical traffic information, the historical average speed of the vehicle at each target position and the number of traffic accidents are counted.

[0074] Step 103: establishing a risk model according to the historical average speed of the vehicle at the target position and the number of traffic accidents; the risk model is used to represent the corresponding relationship between the number of traffic accidents in the target area and the historical average speed of the vehicle.

[0075] That is, in this step, the cloud device establishes a risk model representing the corresponding relationship between the number of traffic accidents in the target area and the historical average speed of the vehicle according to the historical average speed of the vehicle at the target position and the number of traffic accidents.

[0076] Step 104: obtaining the recommended speed of different trajectory points in the target area according to the risk model and the historical speed of each trajectory point.

[0077] In this step, the recommended speed is determined according to the historical speed of each trajectory point and the risk model described above, that is, the number of traffic accidents and the historical average speed are considered, so that the driving efficiency is considered while the driving safety is considered, and the phenomenon of easy emergency braking or the speed being in an undesirable state due to the influence of the speed of surrounding vehicles when the vehicle drives according to the recommended speed is avoided.

[0078] And this step is to obtain the recommended speed of different trajectory points in the target area according to the risk model and the historical speed of each trajectory point, which ensures the fine granularity of the recommended speed and avoids the situation that the speed control of the autonomous vehicle is not smooth.

[0079] The following describes the process of obtaining the historical average speed of the vehicle at the target position and the number of traffic accidents according to historical traffic information in an optional embodiment:

[0080] According to the road nodes in the map information, a first position code corresponding to the road node is obtained by using a preset geographic coding mechanism; wherein the preset geographic coding mechanism can be a geographic hash coding mechanism or other geographic coding mechanism, and preferably, in this embodiment, the preset geographic coding mechanism is a geographic hash coding mechanism.

[0081] Specifically, first, the latitude and longitude of the road nodes are extracted according to the map information (high-definition map) of the selected target area, and the schematic diagram of the road nodes of the target area is as shown in Figure 3 The interval between every two adjacent road nodes is less than 100 meters, and it should be noted that the road nodes are obtained by thinning the map nodes in the map information, as shown in Figure 3 In the case where a road includes multiple cables (lanes), multiple road nodes are obtained for each cable.

[0082] It should be noted that the geographic hash coding mechanism is a general geographic coding method for encoding geographic coordinates such as longitude and latitude into a short alphanumeric string.

[0083] For example, as shown in Table 1 below, the geographic coordinates of the longitude and latitude of the road node are converted into geographic hash codes (i.e., first position codes) using the geographic hash coding mechanism.

[0084] Table 1: First position code table

[0085]

[0086] Then, according to the trajectory points of the vehicle and the historical speed of the vehicle at each trajectory point, the second position code corresponding to the trajectory point of the vehicle and the historical speed corresponding to each second position code are obtained using a preset geographic coding mechanism, for example, as shown in Table 2 below, the geographic coordinates of the longitude and latitude of each trajectory point of the vehicle are converted into geographic hash codes (i.e., second position codes) using the geographic hash coding mechanism, and the historical speed corresponding to each second position code is determined according to the historical speed of the vehicle at each trajectory point.

[0087] Table 2: Second position code table

[0088]

[0089] Then, according to the geographic location of the traffic accident of the vehicle, the third position code corresponding to the geographic location of the traffic accident of the vehicle and the number of traffic accidents corresponding to each third position code are obtained using a preset geographic coding mechanism, for example, as shown in Table 3 below, the geographic coordinates of the longitude and latitude of the geographic location of the traffic accident of the vehicle are converted into geographic hash codes (i.e., third position codes) using the geographic hash coding mechanism, and the number of traffic accidents corresponding to each third position code is counted.

[0090] Table 3: Third position code table

[0091]

[0092] The position codes that coincide in the first position codes, the second position codes and the third position codes are taken as the geographic codes of the target position, and the historical average speed and the number of traffic accidents of the vehicle at the target position are obtained according to the historical speed corresponding to each second position code and the number of traffic accidents corresponding to each third position code, i.e., the geographic hash codes of the road, the trajectory point and the number of traffic accidents are connected, for example, as shown in Table 4 below, Table 4 includes the obtained geographic hash codes of the target position and the historical average speed and the number of traffic accidents of the target position.

[0093] Table 4 Geohash encoding of target location

[0094]

[0095] As an optional embodiment of the present application, the risk model is established according to the historical average speed of the vehicle at the target location and the number of traffic accidents, and the risk model includes:

[0096] The risk model is established with the number of traffic accidents of the vehicle at the target location as the dependent variable and the historical average speed of the vehicle at the target location as the independent variable, and in the risk model, the number of traffic accidents of the vehicle at the target location is a linear function of the historical average speed of the vehicle at the target location.

[0097] Specifically, a risk model with the number of traffic accidents of the vehicle at the target location as the dependent variable is established by using a statistical model (such as a linear regression model, a random forest model, etc.), and the risk model includes the following linear function:

[0098] cnt i = β0+ β i spd i + ∈ i

[0099] Wherein, cnt i represents the number of traffic accidents of the vehicle at the target location, β0represents a constant, spd i represents the historical average speed of the vehicle at the target location, and ∈ i represents a residual error.

[0100] It should be noted that before the risk model is established according to the historical average speed of the vehicle at the target location and the number of traffic accidents, it is necessary to determine whether the historical average speed and the number of traffic accidents conform to the normal distribution, whether normalization needs to be done, etc.

[0101] The following is an embodiment to illustrate the process of obtaining the recommended speed of different trajectory points in the target area according to the risk model and the historical speed of each trajectory point:

[0102] The slope value of the linear function in the risk model is obtained, that is, the slope value of the above linear function is obtained by regression, and the slope value is regarded as the sine value of the included angle between the change relationship of the historical average speed and the number of traffic accidents of the above linear function, that is, tan(β i ).

[0103] For any one of the different trajectory points in the target area (i.e., a target trajectory point), a plurality of historical speeds of the target trajectory point are obtained, and the slope value tan(β idetermining a recommended speed of the target trajectory point according to the slope value and the plurality of historical speeds of the target trajectory point, wherein the recommended speed of the target trajectory point is between the upper limit and the lower limit of the plurality of historical speeds of the target trajectory point, and the recommended speed of the target trajectory point is negatively correlated with the slope value tan(β i ) and the plurality of historical speeds of the target trajectory point.

[0104] Further, the determining the recommended speed of the target trajectory point according to the slope value and the plurality of historical speeds of the target trajectory point comprises:

[0105] arranging the N historical speeds of the target trajectory point in descending order, wherein N represents the sample quantity, i.e. arranging all the N historical speeds of the target trajectory point in descending order.

[0106] obtaining the K value by using the formula: K = 1-tan(β i ) and the plurality of historical speeds of the target trajectory point.

[0107] Further, in the case that K is less than the first preset threshold (preferably, the first preset threshold is 0.5), the Pth historical speed is selected as the recommended speed of the target trajectory point; P is equal to N multiplied by the first preset threshold and is rounded down, for example, the target trajectory point has N = 25 historical speeds, and if K is equal to 0.4, the 12th historical speed is selected as the recommended speed of the target trajectory point.

[0108] Further, in the case that K is greater than the second preset threshold, the Qth historical speed is selected as the recommended speed of the target trajectory point; Q is equal to N multiplied by the second preset threshold and is rounded down. For example, the target trajectory point has N = 25 historical speeds, and if K is equal to 0.8, the 18th historical speed is selected as the recommended speed of the target trajectory point.

[0109] As an optional embodiment of the present application, after the recommended speeds of different trajectory points in the target area are obtained, the method further comprises:

[0110] The recommended speed of each trajectory point is added to the map information of the target area, that is, after the hash code value corresponding to each trajectory point corresponds to a recommended speed, the recommended speed of each trajectory point is supplemented into the road segment attribute of the map information (high-definition map) of the target area. Generally, the road segment attribute includes the road segment speed limit, that is, the information of the recommended speed is additionally added to the road segment attribute of the target area.

[0111] As another optional embodiment of the present application, after obtaining the recommended speeds of the different trajectory points in the target area, the method further comprises:

[0112] Before the target vehicle enters the target area, the recommended speeds of the different trajectory points in the target area are sent to the target vehicle; and the target vehicle is used to determine the final driving speed of the vehicle according to the recommended speeds and first information, wherein the first information includes at least one of the following: the speed of the front vehicle, the current speed of the target vehicle, and the road speed limit.

[0113] Preferably, the cloud device broadcasts the recommended speeds of the different trajectory points in the target area to the target vehicle through the PC5 interface of the RSU before the target vehicle enters the target area. After receiving the recommended speeds of the different trajectory points in the target area, the communication module on the target vehicle sends the recommended speeds of the different trajectory points to the automatic driving module or the auxiliary driving module on the vehicle. The automatic driving module or the auxiliary driving module can fuse and compare the recommended speeds with the speed of the front vehicle, the current speed of the target vehicle, and the road speed limit to determine the final driving speed of the vehicle.

[0114] As another optional embodiment of the present application, after obtaining the recommended speeds of the different trajectory points in the target area, the method further comprises:

[0115] The recommended speed request information sent by the target vehicle is received, that is, the cloud device can establish a data service (such as an Application Program Interface (API) service). When the target vehicle needs to adjust or calculate the speed, the API service is accessed through the UU interface, and the recommended speed request information is sent to the cloud device. The recommended speed request information is used to request the recommended speed of one trajectory point or multiple trajectory points.

[0116] According to the recommended speed request information, the recommended speed of different trajectory points in the target area is sent to the target vehicle; and the target vehicle is configured to determine the final driving speed of the vehicle according to the recommended speed and first information; wherein the first information comprises at least one of the following: the speed of the preceding vehicle, the current speed of the target vehicle and the road speed limit. Specifically, after receiving the recommended speed request information, the cloud device sends the recommended speed of one trajectory point or multiple trajectory points requested by the target vehicle according to the recommended speed request information. After receiving the recommended speed of one trajectory point or multiple trajectory points in the target area, the communication module on the target vehicle sends the recommended speed of different trajectory points to the automatic driving module or the auxiliary driving module on the vehicle. The automatic driving module or the auxiliary driving module can compare and fuse the recommended speed with the speed of the preceding vehicle, the current speed of the target vehicle and the road speed limit to determine the final driving speed of the vehicle.

[0117] The following will be described in detail Figure 4 , the process of determining the final driving speed of the vehicle by the target vehicle, as shown in Figure 4 , the vehicle comprises a communication module, which comprises a UU interface, a PC5 interface, a global navigation satellite system (GNSS) unit, a basic safety message (BSM), a map message unit and a position message unit. The UU interface and the PC5 interface are interfaces for communication between the target vehicle and the cloud device, that is, the recommended speed of different trajectory points sent by the cloud device is received through the UU interface and the PC5 interface. The GNSS unit is used for positioning. The map message unit is used to obtain the map information of the current area. The position message unit is used to obtain the position information of the vehicle and the position information of other vehicles. The BSM is the most widely used application layer message and is used for exchanging safety state data between vehicles.

[0118] The vehicle further comprises an automatic driving module or an auxiliary driving module, which comprises a positioning unit, a perception unit, a path decision unit, a speed control unit and a steering control unit. The positioning unit is used for vehicle positioning. The perception unit is used for perception. The path decision unit is used for path decision by calculating the cost. The speed control unit is used for determining the final driving speed of the vehicle according to the recommended speed, the speed of the preceding vehicle, the current speed of the target vehicle and the road speed limit. The steering control unit is used for steering control of the vehicle.

[0119] After the communication module receives the recommended speed of different trajectory points, the recommended speed is sent to the automatic driving module or the assisted driving module, and a speed control unit in the automatic driving module or the assisted driving module fuses and compares the recommended speed with the speed of the preceding vehicle, the current speed of the target vehicle and the road speed limit to determine the final driving speed of the vehicle.

[0120] In the embodiment of the application, the risk model is established by using the number of traffic accidents and the historical speed of the vehicle, the slope value of the risk model is used to obtain the recommended speed of different trajectory points, the speed adjustment in the micro environment is performed by using the vehicle-road cooperation system, the vehicle with the automatic driving module or the assisted driving module can have the speed control with the active risk avoidance capability by using the vehicle-road cooperation system, the driving risk can be predicted, the driving safety and the driving efficiency are taken into account, and the recommended speed of different trajectory points with fine granularity is obtained, the local speed is fine-tuned, and the rigid behavior of the automatic driving is avoided.

[0121] In the embodiment of the application, the vehicle with the automatic driving module or the assisted driving module can obtain the recommended speed conforming to the road condition and having the risk avoidance prediction, a more conservative driving strategy is adopted in the area with the risk behavior set to avoid the dangerous behavior such as the emergency braking, a more optimal driving strategy is adopted in the area without the risk behavior set, and the driving smoothness is achieved to improve the comfort.

[0122] As shown in Figure 5 the embodiment of the application is a recommended speed determination device, which comprises:

[0123] The information acquisition module 501 is configured to acquire map information of a target area and historical traffic information in the target area, wherein the historical traffic information comprises trajectory points of a vehicle, historical speeds of the vehicle at each trajectory point and geographical positions of traffic accidents of the vehicle.

[0124] The information statistics module 502 is configured to statistically acquire historical average speeds of the vehicle at target positions and the number of traffic accidents according to the map information and the historical traffic information, wherein the target positions are determined according to the map information, the trajectory points of the vehicle and the geographical positions of the traffic accidents of the vehicle.

[0125] The model establishment module 503 is configured to establish a risk model according to the historical average speeds of the vehicle at the target positions and the number of traffic accidents, wherein the risk model is used to represent the corresponding relationship between the number of traffic accidents in the target area and the historical average speeds of the vehicle.

[0126] The first processing module 504 is configured to obtain recommended speeds of different trajectory points in the target area according to the risk model and the historical speed of each trajectory point.

[0127] Optionally, the information statistics module 502 comprises:

[0128] a first processing unit configured to obtain, by using a preset geocoding mechanism, first location codes corresponding to road nodes in the map information according to the road nodes;

[0129] a second processing unit configured to obtain, by using the preset geocoding mechanism, second location codes corresponding to trajectory points of the vehicle and historical speeds corresponding to each second location code according to the trajectory points of the vehicle and historical speeds of the vehicle at each trajectory point;

[0130] a third processing unit configured to obtain, by using the preset geocoding mechanism, third location codes corresponding to geographical positions where the vehicle has traffic accidents and traffic accident frequencies corresponding to each third location code according to the geographical positions where the vehicle has traffic accidents;

[0131] a fourth processing unit configured to take a location code that coincides in the first location codes, the second location codes and the third location codes as a geocode of the target location;

[0132] a fifth processing unit configured to obtain a historical average speed and a traffic accident frequency of the vehicle at the target location according to the historical speed corresponding to each second location code and the traffic accident frequency corresponding to each third location code.

[0133] Optionally, the preset geocoding mechanism is a geohash coding mechanism.

[0134] Optionally, the model establishing module 503 comprises:

[0135] a model establishing unit configured to take a traffic accident frequency of the vehicle at the target location as a dependent variable and take a historical average speed of the vehicle at the target location as an independent variable to establish the risk model, wherein in the risk model, the traffic accident frequency of the vehicle at the target location is a linear function of the historical average speed of the vehicle at the target location.

[0136] Optionally, the first processing module 504 comprises:

[0137] an obtaining unit configured to obtain a slope value of the linear function in the risk model;

[0138] a determining unit configured to obtain a plurality of historical speeds of a target trajectory point and determine a recommended speed of the target trajectory point according to the slope value and the plurality of historical speeds of the target trajectory point, wherein the recommended speed of the target trajectory point is between upper and lower limits of the plurality of historical speeds of the target trajectory point, and the recommended speed of the target trajectory point is negatively correlated with the slope value.

[0139] wherein the target trajectory point is any one of different trajectory points in the target region.

[0140] Optionally, the determining unit is specifically configured to:

[0141] sort the N historical speeds of the target trajectory point in descending order;

[0142] select the Mth historical speed as the recommended speed of the target trajectory point when K is greater than a first preset threshold and less than a second preset threshold;

[0143] wherein M is equal to N multiplied by K and rounded down; and K is equal to 1 minus the slope value;

[0144] the first preset threshold is less than the second preset threshold.

[0145] Optionally, the determining unit is specifically configured to:

[0146] sort the N historical speeds of the target trajectory point in descending order;

[0147] select the Pth historical speed as the recommended speed of the target trajectory point when K is less than or equal to the first preset threshold; and P is equal to N multiplied by the first preset threshold and rounded down.

[0148] Optionally, the determining unit is specifically configured to:

[0149] sort the N historical speeds of the target trajectory point in descending order;

[0150] select the Qth historical speed as the recommended speed of the target trajectory point when K is greater than or equal to the second preset threshold; and Q is equal to N multiplied by the second preset threshold and rounded down.

[0151] Optionally, the apparatus further comprises:

[0152] an information adding module configured to add the recommended speeds of different trajectory points in the target region to map information of the target region.

[0153] Optionally, the apparatus further comprises:

[0154] a first sending module configured to send the recommended speeds of different trajectory points in the target region to a target vehicle before the target vehicle enters the target region; and the target vehicle is configured to determine a final driving speed of the vehicle according to the recommended speeds and first information.

[0155] wherein the first information comprises at least one of:

[0156] The front vehicle speed, the current speed of the target vehicle, and a road speed limit.

[0157] Optionally, the device further comprises:

[0158] The receiving module is configured to receive recommended speed request information sent by the target vehicle;

[0159] The second sending module is configured to send recommended speeds of different trajectory points in the target area to the target vehicle according to the recommended speed request information, so that the target vehicle determines a final driving speed of the vehicle according to the recommended speeds and the first information.

[0160] The first information includes at least one of the following:

[0161] The front vehicle speed, the current speed of the target vehicle, and a road speed limit.

[0162] It should be noted that the recommended speed determination device provided in the embodiments of the present application is a device capable of executing the recommended speed determination method described above, and all embodiments of the recommended speed determination method described above are applicable to the device and can achieve the same or similar technical effects.

[0163] As shown in Figure 6 The present application also provides a recommended speed determination device, which comprises a processor 601, a memory 602, and a program stored in the memory 602 and executable on the processor 601, wherein the program is executed by the processor 601 to implement the recommended speed determination method described above.

[0164] Optionally, the device further comprises a transceiver 603, which is configured to receive and send data under the control of the processor 601.

[0165] Specifically, the processor 601 performs the following processes:

[0166] Obtain map information of a target area and historical traffic information in the target area; the historical traffic information includes trajectory points of vehicles, historical speeds of vehicles at each trajectory point, and geographical positions where traffic accidents of vehicles occur;

[0167] According to the historical traffic information, the historical average speed of vehicles at a target position and the number of traffic accidents are counted; the target position is determined according to the map information, the trajectory points of the vehicles, and the geographical positions where the traffic accidents of the vehicles occur;

[0168] According to the historical average speed of vehicles at the target position and the number of traffic accidents, a risk model is established; the risk model is used to represent the corresponding relationship between the number of traffic accidents in the target area and the historical average speed of vehicles.

[0169] According to the risk model and the historical speed of each trajectory point, a recommended speed of different trajectory points in the target area is obtained.

[0170] Optionally, the processor 601 is configured to:

[0171] According to the road nodes in the map information, a first position code corresponding to each road node is obtained by using a preset geocoding mechanism.

[0172] According to the trajectory points of the vehicle and the historical speed of the vehicle at each trajectory point, a second position code corresponding to each trajectory point of the vehicle and a historical speed corresponding to each second position code are obtained by using a preset geocoding mechanism.

[0173] According to the geographical position of the traffic accident of the vehicle, a third position code corresponding to the geographical position of the traffic accident of the vehicle and a traffic accident frequency corresponding to each third position code are obtained by using a preset geocoding mechanism.

[0174] The position code that coincides in the first position code, the second position code and the third position code is taken as the geocoding of the target position.

[0175] According to the historical speed corresponding to each second position code and the traffic accident frequency corresponding to each third position code, a historical average speed and a traffic accident frequency of the vehicle at the target position are obtained.

[0176] Optionally, the preset geocoding mechanism is a geohashing coding mechanism.

[0177] Optionally, the processor 601 is configured to:

[0178] The traffic accident frequency of the vehicle at the target position is taken as the dependent variable, and the historical average speed of the vehicle at the target position is taken as the independent variable, to establish the risk model; in the risk model, the traffic accident frequency of the vehicle at the target position is a linear function of the historical average speed of the vehicle at the target position.

[0179] Optionally, the processor 601 is configured to:

[0180] The slope value of the linear function in the risk model is obtained.

[0181] For a target trajectory point, a plurality of historical speeds of the target trajectory point are obtained, and according to the slope value and the plurality of historical speeds of the target trajectory point, a recommended speed of the target trajectory point is determined; the recommended speed of the target trajectory point is between the upper and lower limits of the plurality of historical speeds of the target trajectory point, and the recommended speed of the target trajectory point is negatively correlated with the slope value.

[0182] The target trajectory point is any one of different trajectory points in the target region.

[0183] Optionally, the processor 601 is specifically configured to:

[0184] sort the N historical speeds of the target trajectory point in descending order;

[0185] In a case where K is greater than a first preset threshold and less than a second preset threshold, the Mth historical speed is selected as the recommended speed of the target trajectory point;

[0186] M is equal to N multiplied by K and rounded down; and K is equal to 1 minus the slope value.

[0187] The first preset threshold is less than the second preset threshold.

[0188] Optionally, the processor 601 is specifically configured to:

[0189] sort the N historical speeds of the target trajectory point in descending order;

[0190] In a case where K is less than or equal to the first preset threshold, the Pth historical speed is selected as the recommended speed of the target trajectory point; and P is equal to N multiplied by the first preset threshold and rounded down.

[0191] Optionally, the processor 601 is specifically configured to:

[0192] sort the N historical speeds of the target trajectory point in descending order;

[0193] In a case where K is greater than or equal to the second preset threshold, the Qth historical speed is selected as the recommended speed of the target trajectory point; and Q is equal to N multiplied by the second preset threshold and rounded down.

[0194] Optionally, the processor 601 is further configured to:

[0195] add the recommended speeds of the different trajectory points in the target region to map information of the target region.

[0196] Optionally, the transceiver 603 is configured to:

[0197] send the recommended speeds of the different trajectory points in the target region to a target vehicle before the target vehicle enters the target region; and the target vehicle is configured to determine a final driving speed of the vehicle according to the recommended speeds and first information.

[0198] The first information includes at least one of the following:

[0199] a speed of the preceding vehicle, a current speed of the target vehicle, and a road speed limit.

[0200] Optionally, the transceiver 603 is configured to:

[0201] receive the recommended speed request information sent by the target vehicle;

[0202] send the recommended speed of different trajectory points in the target area to the target vehicle according to the recommended speed request information, so that the target vehicle determines a final driving speed of the vehicle according to the recommended speed and the first information.

[0203] The first information includes at least one of the following:

[0204] a speed of the preceding vehicle, a current speed of the target vehicle, and a road speed limit.

[0205] wherein, in the first information, Figure 6 The bus architecture can include any number of interconnecting buses and bridges, depending on the specific application of the processor 601 and the memory represented by the memory 602. The bus architecture can also include various other circuits, which are well known to those skilled in the art, and thus will not be described further. A bus interface provides the user interface 604. The transceiver 603 can be a plurality of elements, including a transmitter and a receiver, which provides a means for communicating with various other apparatuses over a transmission medium. The processor 601 is responsible for managing the bus architecture and general processing, and the memory 602 can store data used by the processor 601 in executing operations.

[0206] In addition, the embodiments of the present application also provide a readable storage medium, and the readable storage medium stores a program, and the program is executed by a processor to implement the steps in any one of the recommended speed determination methods.

[0207] The above is the preferred embodiment of the present application, and it should be pointed out that for ordinary people in the technical field, several improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements are also within the scope of protection of the present application.

Claims

1. A recommended speed determination method characterized by, The method comprises the following steps: obtaining map information of a target area and historical traffic information in the target area; the historical traffic information comprises trajectory points of vehicles, historical speeds of the vehicles at each trajectory point, and geographical positions where the vehicles have traffic accidents; according to the historical traffic information, counting a historical average speed of the vehicles at a target position and a number of traffic accidents; the target position is determined according to the map information, the trajectory points of the vehicles, and the geographical positions where the vehicles have traffic accidents; according to the historical average speed of the vehicles at the target position and the number of traffic accidents, establishing a risk model; the risk model is used to represent a corresponding relationship between the number of traffic accidents and the historical average speed of the vehicles in the target area; according to the risk model and the historical speed of each trajectory point, obtaining a recommended speed of different trajectory points in the target area; wherein, according to the risk model and the historical speed of each trajectory point, obtaining the recommended speed of different trajectory points in the target area comprises: obtaining a slope value of a linear function in the risk model; for a target trajectory point, obtaining a plurality of historical speeds of the target trajectory point, and according to the slope value and the plurality of historical speeds of the target trajectory point, determining a recommended speed of the target trajectory point; the recommended speed of the target trajectory point is between the upper and lower limits of the plurality of historical speeds of the target trajectory point, and the recommended speed of the target trajectory point is negatively correlated with the slope value; wherein, the target trajectory point is any one of the different trajectory points in the target area.

2. The recommended speed determination method according to claim 1, characterized by, According to the historical traffic information, counting a historical average speed of the vehicles at a target position and a number of traffic accidents comprises: using a preset geographic coding mechanism to obtain a first position code corresponding to a road node in the map information according to the road node; using a preset geographic coding mechanism to obtain a second position code corresponding to a trajectory point of the vehicle and a historical speed corresponding to each second position code according to the trajectory point of the vehicle and the historical speed of the vehicle at each trajectory point; using a preset geographic coding mechanism to obtain a third position code corresponding to a geographical position where the vehicle has a traffic accident and a number of traffic accidents corresponding to each third position code according to the geographical position where the vehicle has the traffic accident; taking the position codes that coincide in the first position code, the second position code and the third position code as the geographical code of the target position; according to the historical speed corresponding to each second position code and the number of traffic accidents corresponding to each third position code, obtaining the historical average speed of the vehicles at the target position and the number of traffic accidents.

3. The recommended speed determination method according to claim 2, characterized by, The preset geographic coding mechanism is a geographic hash coding mechanism.

4. The recommended speed determination method according to claim 1, characterized by, According to the historical average speed of the vehicles at the target position and the number of traffic accidents, establishing a risk model comprises: establishing the risk model with the number of traffic accidents of the vehicles at the target position as the dependent variable and the historical average speed of the vehicles at the target position as the independent variable; in the risk model, the number of traffic accidents of the vehicles at the target position is a linear function of the historical average speed of the vehicles at the target position.

5. The recommended speed determination method according to claim 1, characterized by, The method further comprises: adding the recommended speeds of different trajectory points in the target region into the map information of the target region. The method further comprises: sending the recommended speeds of different trajectory points in the target region to the target vehicle before the target vehicle enters the target region; the target vehicle is configured to determine a final driving speed of the vehicle according to the recommended speeds and first information; wherein the first information comprises at least one of the following:

6. The recommended speed determination method according to claim 1, characterized by, a speed of a preceding vehicle, a current speed of the target vehicle, and a road speed limit. The method further comprises: receiving recommended speed request information sent by the target vehicle; 7. The recommended speed determination method according to claim 1, characterized by, sending the recommended speeds of different trajectory points in the target region to the target vehicle according to the recommended speed request information; the target vehicle is configured to determine a final driving speed of the vehicle according to the recommended speeds and first information; wherein the first information comprises at least one of the following: a speed of a preceding vehicle, a current speed of the target vehicle, and a road speed limit.

8. The recommended speed determination method according to claim 1, characterized by, The method further comprises: an information acquisition module configured to acquire map information of a target region and historical traffic information in the target region; the historical traffic information comprises trajectory points of vehicles, historical speeds of the vehicles at each trajectory point, and geographical positions where the vehicles have traffic accidents; 9. The recommended speed determination method according to claim 1, characterized by, an information statistics module configured to statistically determine historical average speeds of vehicles at target positions and numbers of traffic accidents according to the map information and the historical traffic information; the target positions are determined according to the map information, the trajectory points of the vehicles, and the geographical positions where the vehicles have traffic accidents; a model establishment module configured to establish a risk model according to the historical average speeds of the vehicles at the target positions and the numbers of traffic accidents; the risk model is configured to represent a corresponding relationship between the numbers of traffic accidents and the historical average speeds of the vehicles in the target region; ​ 10. The recommended speed determination method according to claim 1, characterized by, ​ ​ ​ ​ ​ 11. A recommended speed determination apparatus characterized by comprising: ​ ​ ​ ​ ​ The first processing module is configured to obtain recommended speeds of different trajectory points in the target area according to the risk model and historical speeds of each trajectory point. The first processing module comprises: An acquisition unit configured to acquire a slope value of a linear function in the risk model; A determination unit configured to, for a target trajectory point, acquire a plurality of historical speeds of the target trajectory point, and determine a recommended speed of the target trajectory point according to the slope value and the plurality of historical speeds of the target trajectory point; the recommended speed of the target trajectory point is between upper and lower limits of the plurality of historical speeds of the target trajectory point, and the recommended speed of the target trajectory point is negatively correlated with the slope value; The target trajectory point is any one of different trajectory points in the target area.

12. A recommended speed determination device characterized by comprising: The program is executed by the processor to implement the steps of the recommended speed determination method according to any one of claims 1 to 10. The program is stored on the readable storage medium and is executed by the processor to implement the steps of the recommended speed determination method according to any one of claims 1 to 10.

13. A readable storage medium, characterized by, ​

Images