A method for implementing a real-time road surface condition detection system under severe weather conditions

Abstract

This invention proposes a method for implementing a real-time road surface condition detection system under severe weather conditions. The system includes a server, multiple robot nodes, multiple vehicle nodes, and multiple access nodes. Access nodes send registration messages to the server to create an access table. After creating data, robot nodes send upload messages to the server to establish a data table. Vehicle nodes send detection messages to obtain real-time data on the physical condition of the road surface. This method can collect real-time parameters of the target road, such as water accumulation and road icing conditions, ensuring driving safety under severe weather conditions and has broad application prospects.

Description

Technical Field

[0001] This invention relates to the field of detection technology, and in particular to a method for implementing a real-time road surface condition detection system under severe weather conditions. Background Technology

[0002] In harsh weather conditions, traditional road surface physical condition detection mainly relies on manual inspections, which has obvious limitations. Specifically, these limitations include low detection accuracy, limited data dimensions, poor real-time performance, and high safety risks for inspection personnel—the accident rate is high in snowy or rainy weather, and low temperatures can easily cause frostbite to inspection personnel.

[0003] This system aims to overcome the above limitations, quickly acquire the physical condition of the road surface under severe weather conditions, and achieve real-time monitoring around the clock. Summary of the Invention

[0004] Purpose of the invention: The technical problem to be solved by the present invention is to provide a method for implementing a real-time road surface condition detection system under severe weather conditions, addressing the shortcomings of the existing technology.

[0005] Technical solution: This invention discloses a method for implementing a real-time road surface condition detection system under severe weather conditions. The system includes a server, multiple robot nodes, multiple vehicle nodes, and multiple access nodes.

[0006] The access node sends a registration message to the server to create an access table; after the robot node creates data, it sends an upload message to the server to establish a data table; the vehicle node sends a detection message to obtain the real-time physical status of the road surface.

[0007] If the distance between the coordinates of the vehicle node that receives the detection message and the destination coordinates in the detection message is less than the distance between the source coordinates and the destination coordinates in the detection message, then the source coordinates of the detection message are set as the vehicle node's own coordinates, and the detection message is forwarded.

[0008] If the access node that receives the detection message does not have a road segment table entry whose destination coordinate tuple and source coordinate tuple are equal to the destination coordinate tuple and source coordinate tuple in the detection message, then it creates a road segment table entry and forwards the detection message from the wired interface.

[0009] The server that receives the detection message sends the road surface message from the interface where the detection message was received; if the access node that receives the road surface message has a road segment table entry whose destination coordinate tuple matches any data table entry in the road surface message, then selects the entry and performs the following operation for each selected matching road segment table entry: set the destination coordinate of the road surface message to the coordinate in the source coordinate tuple of the road segment table entry that is not equal to its own coordinate, and forward the road surface message.

[0010] If the distance between the coordinates of the vehicle node that receives the road message and the destination coordinates in the road message is less than the distance between the source coordinates and the destination coordinates in the road message, then the source coordinates of the road message are set to the vehicle node's own coordinates, and the road message is forwarded.

[0011] If the vehicle node that sent the detection message receives the road surface message, it saves the data table in the road surface message.

[0012] The method further includes:

[0013] Upon receiving the detection message, the server selects all data table entries whose coordinate tuples are equal to the destination coordinate tuple in the detection message, and selects an access entry whose interface ID is equal to the interface ID of the interface that received the detection message. In the road surface message sent by the server, the data table contains all the selected data table entries, the source coordinates are the coordinates of the selected access entry, and the destination coordinates are empty.

[0014] The method further includes:

[0015] If the distance between the robot node coordinates that received the upload message and the destination coordinates in the upload message is less than the distance between the source coordinates and the destination coordinates in the upload message, and there is no sequence list entry with a sequence number equal to the sequence number in the upload message, then the robot node sets a time variable, with the initial value of the time variable equal to the current time t1, sets a message variable whose value is equal to the received upload message, creates a sequence list entry with a sequence number equal to the sequence number in the upload message, and sets the lifetime of the entry to the maximum value. If, within the time period from time t1 to time t1 + T × d1 / d2, the robot node does not receive an upload message with a sequence number equal to the sequence number in the message variable, then it sets the source coordinates of the received upload message to its own coordinates and forwards the upload message. T is a preset time, d1 is the distance between the robot coordinates and the destination coordinates in the upload message, and d2 is the distance between the source coordinates and the destination coordinates in the upload message.

[0016] The method further includes:

[0017] The access node that receives the upload message forwards the upload message from the wired interface;

[0018] If the server receiving the upload message has a data entry whose coordinate tuple and identifier are equal to those in the upload message, then the server sets the data of the data entry to the data in the upload message and sets its lifetime to the maximum value. Otherwise, the server creates a new data entry whose coordinate tuple and identifier are equal to those in the upload message, sets the data of the new data entry to the data in the upload message, and sets its lifetime to the maximum value.

[0019] The method further includes:

[0020] Each access node stores a road segment table. Each road segment table entry contains a target coordinate tuple, a source coordinate tuple, and a lifecycle. The initial value of the road segment table is an empty table.

[0021] The detection message contains a message ID, a destination coordinate tuple, a source coordinate tuple, source coordinates, and destination coordinates;

[0022] The road surface message includes a message ID, a data table, source coordinates, and destination coordinates;

[0023] In the detection message sent by the vehicle node, the message ID is 3, the destination coordinate tuple is preset, the source coordinate tuple is the coordinate tuple of the road segment where the vehicle node is located, the source coordinate is equal to the current coordinate of the vehicle node, and the destination coordinate is set to any coordinate in the source coordinate tuple.

[0024] The method further includes:

[0025] In the road segment table entry created by the access node that receives the detection message, the destination coordinate tuple and the source coordinate tuple are equal to the destination coordinate tuple and the source coordinate tuple in the detection message, respectively, and the lifetime is equal to the maximum value.

[0026] The method further includes:

[0027] Upon receiving a road surface message, the access node selects all road segment entries whose destination coordinate tuples are equal to any data table entry coordinate tuple in the road surface message and deletes these road segment entries.

[0028] Upon receiving a road surface message, the vehicle node performs the following operation for each data table entry DE1 in the road surface message: It determines whether its own data table contains a data table entry whose coordinate tuple and identifier are equal to those of data table entry DE1. If it exists, it updates the data of that data table entry to the data in data table entry DE1 and sets its lifetime to the maximum value. Otherwise, it creates a new data table entry whose coordinate tuple, identifier, and data are equal to those of data table entry DE1, and sets its lifetime to the maximum value.

[0029] The method further includes:

[0030] Each type of data is uniquely identified by an identifier;

[0031] The server, each robot, and each vehicle node each store a data table. Each data table item contains a coordinate tuple, an identifier, data, and lifecycle.

[0032] Each robot node stores a sequence list, and each sequence list entry contains a sequence number and a lifecycle.

[0033] The uploaded message contains a message ID, sequence number, coordinate tuple, data, identifier, source coordinates, and destination coordinates;

[0034] The robot node creates data and a random number. In the upload message it sends, the message ID is 2, the sequence number is the created random number, the coordinate tuple is the coordinate tuple of the road segment where the robot node is located, the data is the created data, the identifier is the identifier of the created data, the source coordinates are its current coordinates, and the destination coordinates are set to any coordinate in the coordinate tuple.

[0035] The method further includes:

[0036] Access nodes are evenly distributed on both sides of the road, and each access node has unique coordinates; the road between two adjacent access nodes is called a road segment, which is uniquely identified by a coordinate tuple of the two adjacent access nodes, and the coordinate tuple is composed of the coordinates of the two connected access nodes.

[0037] Each access node is configured with one wired interface and one wireless interface. The wired interface connects to the server, and the wireless interface connects to the vehicle node or robot node. The server is configured with multiple wired interfaces, the number of which is greater than the total number of all access nodes in the system. Each access node is connected to one wired interface. Each interface is uniquely identified by an interface ID.

[0038] Each vehicle node is configured with a wireless interface to connect to other vehicle nodes or access nodes; each robot node is configured with a wireless interface to connect to other robot nodes or access nodes; each message is uniquely identified by a message ID; the server maintains an access table, and each access table entry contains the interface ID, coordinates, and lifecycle.

[0039] The method further includes:

[0040] The registration message includes a message ID and coordinates. In the registration message sent by the access node from the wired interface, the message ID is 1, and the coordinates are the coordinates of the access node. After receiving the registration message, if the server has an access entry whose interface ID is equal to the interface ID of the interface that received the registration message, then the coordinates of the access entry are set to the coordinates in the registration message, and the lifespan is set to the maximum value. Otherwise, an access entry is created, whose interface ID is equal to the interface ID of the interface that received the registration message, and the coordinates of the access entry are set to the coordinates in the registration message, and the lifespan is set to the maximum value.

[0041] Beneficial Effects: This invention proposes a method for implementing a real-time road surface condition detection system under severe weather conditions. This method can collect real-time parameters of the target road, such as water accumulation and road icing conditions, effectively overcoming the limitations of existing manual inspections, ensuring driving safety under severe weather conditions, and has broad application prospects. Attached Figure Description

[0042] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0043] Figure 1 This is a flowchart of the real-time road surface physical condition detection system of the present invention.

[0044] Figure 2 Create a flowchart for the access table.

[0045] Figure 3 This is a flowchart for real-time data acquisition of road surface physical conditions.

[0046] Figure 4 This is a flowchart for real-time data detection of road surface physical conditions. Detailed Implementation

[0047] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0048] Figure 1 This is a flowchart of the real-time road surface physical state detection system of the present invention; Figure 2 A flowchart is created for the access table. The system includes robot nodes, vehicle nodes, access nodes, and a server; the system contains only one server.

[0049] The access nodes are evenly distributed on both sides of the road, and each access node has unique coordinates.

[0050] The road between two adjacent access nodes is called a road segment, which is composed of a coordinate tuple of the two adjacent access nodes.<CO0, CO00> Unique identifier: CO0 represents the coordinates of one access node, and CO00 represents the coordinates of another access node;

[0051] Robot nodes are evenly distributed on the road segments that need to be detected. They can establish continuous paths to any access node on the road segment and monitor that no vehicle nodes are traveling on the road segment.

[0052] Vehicle nodes are evenly distributed on road sections where traffic can proceed normally, and can establish continuous paths to any access node on the road section. Robot nodes are not included on road sections where traffic can proceed normally.

[0053] The access node is configured with a wired interface and a wireless interface. The wired interface connects to the server, and the wireless interface connects to the vehicle node or robot node.

[0054] The server is configured with multiple wired interfaces, which is greater than the total number of all access nodes in the system. Each access node is connected to one wired interface. Each interface is uniquely identified by an interface ID, and the interface with interface ID x is abbreviated as interface x.

[0055] Each vehicle node is configured with a wireless interface to connect to other vehicle nodes or access nodes.

[0056] The robot node is configured with a wireless interface to connect with other robot nodes or access nodes;

[0057] Each message is uniquely identified by a message ID;

[0058] The server maintains an access table, and each access table entry contains the interface ID, coordinates, and lifecycle.

[0059] The registration message includes a message ID and coordinates;

[0060] Access node AP3, with coordinates CO3, periodically performs the following operations:

[0061] Step 101: Begin;

[0062] Step 102: Access node AP3 sends a registration message from the wired interface. The message ID of this message is 1, and the coordinates are CO3.

[0063] Step 103: After receiving the registration message from interface x0, the server determines whether there is an access entry with an interface ID equal to x0. If it exists, the coordinates of the entry are set to the coordinates in the registration message, and the lifecycle is set to the maximum value. Otherwise, an access entry is created with an interface ID equal to x0, the coordinates of the entry are set to the coordinates in the registration message, and the lifecycle is set to the maximum value.

[0064] Step 104: End.

[0065] The access node sends a registration message through the above process to establish an access table on the server. The server can then obtain the coordinates of the connected access node based on the interface ID of each entry in the access table, thereby enabling the correct transmission of real-time data on the physical state of the road surface and ensuring safe driving. The above process ensures the validity of the access table through a lifecycle, thus ensuring the validity and correctness of the access table.

[0066] Figure 3 This is a flowchart illustrating the real-time data acquisition process for road surface physical conditions. Each data type is uniquely identified by an identifier, such as icing status.

[0067] The server, each robot, and each vehicle node each store a data table. Each data table item contains a coordinate tuple, an identifier, data, and lifecycle.

[0068] Each robot node stores a sequence list, and each sequence list entry contains a sequence number and a lifecycle.

[0069] The uploaded message contains a message ID, sequence number, coordinate tuple, data, identifier, source coordinates, and destination coordinates;

[0070] Robot node R1 is located on the detection segment RS1, which is identified by the coordinate tuple TP1. If robot node R1 creates data identified by identifier NA1, the following operation is performed:

[0071] Step 201: Begin;

[0072] Step 202: Robot node R1 creates a random number RN1 and sends an upload message. The message ID is 2, the sequence number is RN1, the coordinate tuple is TP1, the data is the created data, the identifier is NA1, the source coordinates are its current coordinates, and the destination coordinates are set to any coordinate in the coordinate tuple TP1.

[0073] Step 203: If the access node receives the upload message, proceed to step 208; otherwise, proceed to step 204.

[0074] Step 204: The robot node that receives the upload message determines whether the distance between its own coordinates and the destination coordinates in the message is less than the distance between the source coordinates and the destination coordinates in the message. If so, proceed to step 205; otherwise, proceed to step 209.

[0075] Step 205: The robot node that receives the upload message determines whether there is a sequence list entry whose sequence number is equal to the sequence number in the upload message. If it exists, proceed to step 209; otherwise, proceed to step 206.

[0076] Step 206: The robot node that receives the upload message sets a time variable, with the initial value of the time variable equal to the current time t1. It also sets a message variable, with the initial value of the message variable equal to the received upload message. A sequence list entry is created, with the sequence number of the entry equal to the sequence number in the upload message. The lifetime of the entry is set to the maximum value, for example, 500ms. If the robot node does not receive an upload message with a sequence number equal to the sequence number in the message variable within the time period from time t1 to time t1 + T × d1 / d2, then proceed to step 207; otherwise, proceed to step 209. Here, T is a preset time, for example, equal to 1s, d1 is the distance between the robot coordinates and the destination coordinates in the upload message, and d2 is the distance between the source coordinates and the destination coordinates in the upload message.

[0077] Step 207: The robot node that receives the upload message sets the source coordinates of the message to its own coordinates, forwards the upload message, and executes step 203;

[0078] Step 208: The access node that receives the upload message forwards the upload message from the wired interface. The server that receives the upload message determines whether there is a data entry whose coordinate tuple and identifier are equal to the coordinate tuple and identifier in the upload message. If it exists, the data of the entry is set to the data in the message, and the lifetime is set to the maximum value. Otherwise, the server creates a data entry whose coordinate tuple and identifier are equal to the coordinate tuple and identifier in the upload message, sets the data of the entry to the data in the message, and sets the lifetime to the maximum value.

[0079] Step 209: End.

[0080] After the robot node creates real-time road physical state data, it sends an upload message through the above process to upload the real-time road physical state data to the server for storage. In this way, the server can provide real-time road physical state data to other vehicle nodes. The innovations of the above process include: (1) The robot node selects the shortest route path through coordinates to transmit the data to the server; (2) The use of sequence lists effectively prevents repeated message forwarding, thereby improving the upload efficiency of real-time road physical state data; (3) The robot coordinates are used to set time variables to ensure that the robot node closest to the access node transmits data, reducing the number of robot nodes transmitting data, ensuring the real-time nature of the real-time road physical state data, and reducing the transmission of redundant data.

[0081] Figure 4 This is a flowchart for real-time data detection of road surface physical conditions. Each access node stores a road segment table, and each road segment table entry contains a target coordinate tuple, a source coordinate tuple, and a lifecycle; the initial value of the road segment table is an empty table.

[0082] The detection message contains a message ID, a destination coordinate tuple, a source coordinate tuple, and source and destination coordinates;

[0083] The road surface message includes a message ID, a data table, source coordinates, and destination coordinates;

[0084] Road segment RS1 is identified by coordinate tuple TP1. Vehicle node V2 is located on normal road segment RS2, which is identified by coordinate tuple TP2. If the server has a data table entry with coordinate tuple equal to TP1, vehicle node V2 executes the following procedure to obtain the data table for road segment RS1:

[0085] Step 301: Begin;

[0086] Step 302: Vehicle node V2 sends a detection message with message ID 3, destination coordinate tuple TP1, source coordinate tuple TP2, source coordinate equal to its current coordinate, and destination coordinate equal to any coordinate in coordinate tuple TP2.

[0087] Step 303: If the access node receives the detection message, proceed to step 306; otherwise, proceed to step 304.

[0088] Step 304: The vehicle node that receives the detection message determines whether the distance between its own coordinates and the destination coordinates in the message is less than the distance between the source coordinates and the destination coordinates in the message. If so, proceed to step 305; otherwise, proceed to step 318.

[0089] Step 305: The vehicle node that receives the detection message sets the source coordinates of the message to its own coordinates, forwards the detection message, and executes step 303;

[0090] Step 306: The access node that receives the detection message determines whether there is a road segment entry whose destination coordinate tuple and source coordinate tuple are equal to the destination coordinate tuple and source coordinate tuple in the detection message, respectively. If it exists, proceed to step 309; otherwise, proceed to step 307.

[0091] Step 307: The access node that receives the detection message creates a road segment entry. The destination coordinate tuple and source coordinate tuple of the road segment entry are equal to the destination coordinate tuple and source coordinate tuple in the detection message, respectively. The lifecycle is set to the maximum value. The maximum lifecycle value is preset, for example, 1 second. The access node forwards the detection message from the wired interface.

[0092] Step 308: The server that receives the detection message from interface x1 selects all data table entries whose coordinate tuples are equal to the destination coordinate tuple in the detection message, selects an access table entry whose interface ID is equal to x1, and sends a road surface message from interface x1 with message ID 4. The data table contains all selected data table entries, the source coordinates are equal to the coordinates of the selected access table entry, and the destination coordinates are empty.

[0093] Step 309: If the access node receives the road surface message, proceed to step 310; otherwise, proceed to step 313.

[0094] Step 310: The access node that receives the road surface message determines whether there is a road segment table entry whose destination coordinate tuple is equal to the coordinate tuple of any data table entry in the data table of the message. If it exists, proceed to step 311; otherwise, proceed to step 318.

[0095] Step 311: The access node that receives the road message selects all road segment entries whose destination coordinate tuple is equal to the coordinate tuple of any data table entry in the message. For each selected road segment entry, the following operation is performed: select a coordinate in the source coordinate tuple of the road segment entry, which is not equal to its own coordinate, set the destination coordinate of the road message as the selected coordinate, and forward the road message.

[0096] Step 312: The access node that receives the road surface message selects all road segment entries whose destination coordinate tuple is equal to any data table entry coordinate tuple in the message, deletes these road segment entries, and proceeds to step 309.

[0097] Step 313: If vehicle node V2 receives a road surface message, proceed to step 317; otherwise, proceed to step 314.

[0098] Step 314: The vehicle node that receives the road message performs the following operation for each data table entry DE1 in the road message: The vehicle node determines whether there is a data table entry in its own data table whose coordinate tuple and identifier are equal to the coordinate tuple and identifier of data table entry DE1, respectively. If it exists, the data of the entry is updated to the data in data table entry DE1, and the lifecycle is set to the maximum value. Otherwise, a data table entry is created, whose coordinate tuple and identifier are equal to the coordinate tuple and identifier of data table entry DE1, the data of the entry is set to the data in data table entry DE1, and the lifecycle is set to the maximum value.

[0099] Step 315: The vehicle node that receives the road message determines whether the distance between its own coordinates and the destination coordinates in the message is less than the distance between the source coordinates and the destination coordinates in the message. If so, proceed to step 316; otherwise, proceed to step 318.

[0100] Step 316: The vehicle node that receives the road surface message sets the source coordinates of the message to its own coordinates, forwards the road surface message, and executes step 309;

[0101] Step 317: The vehicle node V2 that receives the road surface message saves the data table in the road surface message;

[0102] Step 318: End.

[0103] Vehicle nodes send detection messages and road surface messages through the above process to obtain real-time data on the physical state of the road surface from the server. In the above process, data sharing between multiple vehicle nodes is realized through road segment table entries, thereby realizing real-time monitoring of the physical state of the road surface. The specific innovations include: (1) Access nodes use road segment tables to achieve aggregation, avoiding repeated forwarding of detection messages and greatly improving detection efficiency; (2) Vehicles can obtain real-time data on the physical state of the road surface of any detection road segment, realizing remote monitoring; (3) Using coordinates reduces the number of vehicle nodes forwarding data and minimizes the data forwarding delay; (4) All vehicles on the source road segment can obtain the real-time data table of the physical state of the target road surface, realizing multi-dimensional data monitoring and improving detection efficiency; (5) Using the coordinates of the access node to transmit real-time data on the physical state of the road surface avoids the problem of data acquisition failure caused by the mobility of vehicle nodes and ensures that vehicle nodes obtain data.

[0104] Example 1

[0105] Based on the simulation parameters in Table 1, this embodiment simulates the implementation method of a real-time road surface condition detection system under severe weather conditions in this invention. The performance analysis is as follows: When the vehicle is far from the access node, the success rate of the vehicle node in obtaining road surface physical condition data decreases. When the vehicle is close to the access node, the success rate of the vehicle node in obtaining real-time road surface physical condition increases. The average success rate of the vehicle in obtaining road surface physical condition is 97.9%.

[0106] Table 1

[0107] Parameter Description Parameter value MAC protocol IEEE 802.11 Simulation times 50 Transmission radius 250 meters Simulation time 6 hours

[0108] This invention provides a method for implementing a real-time road surface condition detection system under severe weather conditions. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment of the invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A method for implementing a real-time road surface condition detection system under severe weather conditions, characterized in that, The system includes a server, multiple robot nodes, multiple vehicle nodes, and multiple access nodes. The access nodes are evenly distributed on both sides of the road, and each access node has unique coordinates. The road between two adjacent access nodes is called a road segment, which is uniquely identified by a coordinate tuple of the two adjacent access nodes. Each access node is configured with one wired interface and one wireless interface. The wired interface connects to the server, and the wireless interface connects to the vehicle node or robot node. The server is configured with multiple wired interfaces, the number of which is greater than the total number of all access nodes in the system. Each access node is connected to one wired interface. Each interface is uniquely identified by an interface ID. Each vehicle node is configured with a wireless interface to connect with other vehicle nodes or access nodes; each robot node is configured with a wireless interface to connect with other robot nodes or access nodes; each message is uniquely identified by a message ID; the server maintains an access table, and each entry in the access table contains the interface ID, coordinates, and lifecycle. The access node sends a registration message to the server to create an access table; after the robot node creates data, it sends an upload message to the server to establish a data table; the vehicle node sends a detection message to obtain real-time data on the physical state of the road surface. If the distance between the coordinates of the vehicle node that receives the detection message and the destination coordinates in the detection message is less than the distance between the source coordinates and the destination coordinates in the detection message, then the source coordinates of the detection message are set as the vehicle node's own coordinates, and the detection message is forwarded. If the access node that receives the detection message does not have a road segment table entry whose destination coordinate tuple and source coordinate tuple are equal to the destination coordinate tuple and source coordinate tuple in the detection message, then it creates a road segment table entry and forwards the detection message from the wired interface. The server that receives the detection message sends the road surface message from the interface where the detection message was received; if the access node that receives the road surface message has a road segment table entry whose destination coordinate tuple matches any data table entry in the road surface message, then selects the entry and performs the following operation for each selected matching road segment table entry: set the destination coordinate of the road surface message to the coordinate in the source coordinate tuple of the road segment table entry that is not equal to its own coordinate, and forward the road surface message. If the distance between the coordinates of the vehicle node that receives the road message and the destination coordinates in the road message is less than the distance between the source coordinates and the destination coordinates in the road message, then the source coordinates of the road message are set to the vehicle node's own coordinates, and the road message is forwarded. If the vehicle node that sent the detection message receives the road surface message, it saves the data table in the road surface message.

2. The implementation method of the real-time road surface condition detection system under severe weather conditions according to claim 1, characterized in that, The method further includes: Upon receiving the detection message, the server selects all data table entries whose coordinate tuples are equal to the destination coordinate tuple in the detection message, and selects an access entry whose interface ID is equal to the interface ID of the interface that received the detection message. In the road surface message sent by the server, the data table contains all the selected data table entries, the source coordinates are the coordinates of the selected access entry, and the destination coordinates are empty.

3. The implementation method of the real-time road surface condition detection system under severe weather conditions according to claim 1, characterized in that, The method further includes: If the distance between the robot node coordinates that received the upload message and the destination coordinates in the upload message is less than the distance between the source coordinates and the destination coordinates in the upload message, and there is no sequence list entry with a sequence number equal to the sequence number in the upload message, then the robot node sets a time variable, with the initial value of the time variable equal to the current time t1, sets a message variable whose value is equal to the received upload message, creates a sequence list entry with a sequence number equal to the sequence number in the upload message, and sets the lifetime of the entry to the maximum value. If, within the time period from time t1 to time t1+T×d1 / d2, the robot node does not receive an upload message with a sequence number equal to the sequence number in the message variable, then it sets the source coordinates of the received upload message to its own coordinates and forwards the upload message. T is a preset time, d1 is the distance between the robot coordinates and the destination coordinates in the upload message, and d2 is the distance between the source coordinates and the destination coordinates in the upload message.

4. A method for implementing a real-time road surface condition detection system under severe weather conditions according to any one of claims 1 to 3, characterized in that, The access node that receives the upload message forwards the upload message from the wired interface; If the server receiving the upload message has a data entry whose coordinate tuple and identifier are equal to those in the upload message, then the server sets the data of the data entry to the data in the upload message and sets its lifetime to the maximum value. Otherwise, the server creates a new data entry whose coordinate tuple and identifier are equal to those in the upload message, sets the data of the new data entry to the data in the upload message, and sets its lifetime to the maximum value.

5. A method for implementing a real-time road surface condition detection system under severe weather conditions according to any one of claims 1 to 3, characterized in that, The method further includes: Each access node stores a road segment table. Each road segment table entry contains a target coordinate tuple, a source coordinate tuple, and a lifecycle. The initial value of the road segment table is an empty table. The detection message contains a message ID, a destination coordinate tuple, a source coordinate tuple, source coordinates, and destination coordinates; The road surface message includes a message ID, a data table, source coordinates, and destination coordinates; In the detection message sent by the vehicle node, the message ID is 3, the destination coordinate tuple is preset, the source coordinate tuple is the coordinate tuple of the road segment where the vehicle node is located, the source coordinate is equal to the current coordinate of the vehicle node, and the destination coordinate is set to any coordinate in the source coordinate tuple.

6. A method for implementing a real-time road surface condition detection system under severe weather conditions according to any one of claims 1 to 3, characterized in that, The method further includes: In the road segment table entry created by the access node that receives the detection message, the destination coordinate tuple and the source coordinate tuple are equal to the destination coordinate tuple and the source coordinate tuple in the detection message, respectively, and the lifetime is equal to the maximum value.

7. A method for implementing a real-time road surface condition detection system under severe weather conditions according to any one of claims 1 to 3, characterized in that, Upon receiving a road surface message, the access node selects all road segment entries whose destination coordinate tuples are equal to any data table entry coordinate tuple in the road surface message and deletes these road segment entries. Upon receiving a road surface message, the vehicle node performs the following operation for each data table entry DE1 in the road surface message: It determines whether its own data table contains a data table entry whose coordinate tuple and identifier are equal to those of data table entry DE1. If it exists, it updates the data of that data table entry to the data in data table entry DE1 and sets its lifetime to the maximum value. Otherwise, it creates a new data table entry whose coordinate tuple, identifier, and data are equal to those of data table entry DE1, and sets its lifetime to the maximum value.

8. A method for implementing a real-time road surface condition detection system under severe weather conditions according to any one of claims 1 to 3, characterized in that, The method further includes: Each type of data is uniquely identified by an identifier; the server, each robot, and each vehicle node each maintain a data table, and each data table entry contains a coordinate tuple, identifier, data, and lifecycle; each robot node maintains a sequence table, and each sequence table entry contains a sequence number and lifecycle; the uploaded message contains a message ID, sequence number, coordinate tuple, data, identifier, source coordinates, and destination coordinates; The robot node creates data and a random number. In the upload message it sends, the message ID is 2, the sequence number is the created random number, the coordinate tuple is the coordinate tuple of the road segment where the robot node is located, the data is the created data, the identifier is the identifier of the created data, the source coordinates are its current coordinates, and the destination coordinates are set to any coordinate in the coordinate tuple.

9. A method for implementing a real-time road surface condition detection system under severe weather conditions according to any one of claims 1 to 3, characterized in that, The method further includes: The registration message includes a message ID and coordinates. In the registration message sent by the access node from the wired interface, the message ID is 1, and the coordinates are the coordinates of the access node. After receiving the registration message, if the server has an access entry whose interface ID is equal to the interface ID of the interface that received the registration message, then the coordinates of the access entry are set to the coordinates in the registration message, and the lifespan is set to the maximum value. Otherwise, an access entry is created, whose interface ID is equal to the interface ID of the interface that received the registration message, and the coordinates of the access entry are set to the coordinates in the registration message, and the lifespan is set to the maximum value.

Images