CN110996292B

CN110996292B - Implementation method of safety alarm system based on Internet of vehicles

Info

Publication number: CN110996292B
Application number: CN201911177788.2A
Authority: CN
Inventors: 王晓喃; 蔡少豪; 陆奕敏
Original assignee: Changshu Institute of Technology
Current assignee: Changshu Institute of Technology
Priority date: 2019-11-27
Filing date: 2019-11-27
Publication date: 2021-10-22
Anticipated expiration: 2039-11-27
Also published as: CN110996292A

Abstract

The invention provides a method for realizing a safety alarm system based on an internet of vehicles, wherein the internet of vehicles consists of equipment and access nodes; the device comprises a pedestrian node and a vehicle node; the pedestrian node is an intelligent device which contains a mobile phone number and can carry out data communication. The vehicle node can rapidly acquire the service data through the method provided by the invention, so that the delay and cost for acquiring the service data are reduced, and the safety alarm is realized, so that the traffic accident is effectively avoided, and the method has wide application prospect.

Description

Implementation method of safety alarm system based on Internet of vehicles

Technical Field

The invention relates to an implementation method, in particular to an implementation method of a safety alarm system based on Internet of vehicles.

Background

The internet of vehicles is a service model that is built on vehicles and can provide local services. In recent years, much research has been devoted to the internet of vehicles in order to enable vehicle drivers to quickly obtain network services. With the development of network technology, the internet of vehicles will become a mode for providing services in the future.

At present, the implementation mode of the internet of vehicles is realized through broadcasting, so that both delay and cost are large, and the network service performance is reduced. Therefore, how to reduce the delay and cost of providing services by the car-mounted network becomes a hot issue of research in recent years.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to solve the technical problem of the prior art and provides a method for realizing a safety alarm system based on Internet of vehicles. The vehicle cloud is realized by replacing broadcasting with unicast, so that delay and cost of service provided by a vehicle network are reduced, and network service performance is effectively improved.

The technical scheme is as follows: the invention discloses a method for realizing a safety alarm system based on an internet of vehicles, wherein the internet of vehicles consists of equipment and access nodes; the device comprises a pedestrian node and a vehicle node; the pedestrian node is an intelligent device which contains a mobile phone number and can carry out data communication; for example, a person walking on the roadside and carrying a smart device, including a cell phone, etc.;

each vehicle node is provided with an interface W1 and an interface W2, wherein the interface W1 is used for communicating with the pedestrian node, and the interface W2 is used for communicating with other vehicle nodes or access nodes;

each access node is provided with an interface W3 and an interface W4, wherein the interface W3 is used for communicating with a pedestrian node, and the interface W4 is used for communicating with a vehicle node;

a pedestrian node is provided with an interface W0;

the interface W0, the interface W1, the interface W2, the interface W3 and the interface W4 are all wireless interfaces;

the communication radius of the interface W0, the interface W1 and the interface W3 is R1, such as 50m-100 m; the communication radius of the interface W2 and the interface W4 is R2, such as 250m-300 m;

each access node has unique coordinates;

each pedestrian node, each vehicle node and each access node have unique addresses, and each address is composed of coordinates and a hardware ID; the hardware ID of the pedestrian node is the telephone number of the pedestrian node, and the hardware ID of the vehicle node is the license plate number of the vehicle node; the hardware ID of the access node is the media access control address of the access node, namely the MAC address;

a device obtains the coordinates of each access node through an electronic map;

a message is uniquely identified by a message type, as shown in the following table:

a pedestrian node, a vehicle node and an access node respectively store a neighbor table, and each neighbor table comprises an address, an interface and a life cycle;

a neighbor message contains message type, role and address; the angular color value is 1 to represent a vehicle node, the angular color value is 0 to represent an access node, and the role value is 2 to represent a pedestrian node;

the vehicle node V1 periodically performs the following operations:

step 101: starting;

step 102: the vehicle node V1 constructs an address, the coordinates of the address are the current coordinates of the vehicle node V1, and the hardware ID is the license plate number of the vehicle node V1; the vehicle node V1 sends a neighbor message from the interface W1 and the interface W2 respectively, wherein the message type value of the neighbor message is 1, the angle value is 1, and the address is a constructed address;

step 103: if the pedestrian node receives the neighbor message from the interface W0, step 104 is executed, otherwise step 105 is executed;

step 104: the pedestrian node which receives the neighbor message from the interface W0 checks the neighbor table, if a neighbor table entry exists, the hardware ID of the address of the neighbor table entry is equal to the hardware ID of the address of the neighbor message, the address of the neighbor table entry is updated to the address of the neighbor message, the interface domain value is updated to the interface W0, and the life cycle is set to the maximum value; otherwise, the pedestrian node creates a neighbor table entry, the address of the neighbor table entry is equal to the address of the neighbor message, the interface domain value is interface W0, the life cycle is set to the maximum value, and step 108 is executed;

step 105: after the access node receives the neighbor message from the interface W4 or the vehicle node receives the neighbor message from the interface W2, the role value of the neighbor message is checked, if the role value is equal to 0 or 1, the step 106 is executed, otherwise, the step 107 is executed;

step 106: the access node that received the neighbor message from the interface W4 or the vehicle node that received the neighbor message from the interface W2 looks at the neighbor table, and if there is one neighbor table entry, the hardware ID of the neighbor table entry address is equal to the hardware ID of the neighbor message address, the address of the neighbor table entry is updated to the address of the neighbor message, if the access node receives the neighbor message from W4, the interface domain value is updated to interface W4, otherwise, the interface domain value is updated to interface W2, the lifetime is set to the maximum value, if there is no neighbor entry as described above, the access node or the vehicle node creates a neighbor entry, the address of which equals the address of the neighbor message, if the access node receives the neighbor message from W4, setting the interface domain value as interface W4, otherwise, setting the interface domain value as interface W2, and setting the life cycle of the neighbor table entry as the maximum value;

step 107: the access node receives the neighbor message from the interface W3 or the vehicle node receives the neighbor message from the interface W1 and then checks the neighbor table, if a neighbor table entry exists, the hardware ID of the address of the neighbor table entry is equal to the hardware ID of the address of the neighbor message, the address of the neighbor table entry is updated to the address of the neighbor message, if the access node receives the neighbor message from the interface W3, the interface domain value is updated to the interface W3, otherwise, the interface domain value is updated to the interface W1, and the life cycle of the neighbor table entry is set to the maximum value; if the neighbor table entry does not exist, the access node or the vehicle node creates a neighbor table entry, the address of the neighbor table entry is equal to the address of the neighbor message, if the access node receives the neighbor message from the interface W3, the interface domain value is set to be the interface W3, otherwise, the interface domain value is set to be the interface W1, and the life cycle of the neighbor table entry is set to be the maximum value;

step 108: and (6) ending.

The vehicle node establishes the neighbor table through the process, so that the real-time coordinate and the license plate number of the vehicle node can be obtained through the address of the neighbor table, and whether the distance between the adjacent pedestrian nodes or the adjacent vehicle nodes is small or not is judged, and the traffic accident is effectively avoided.

In the method of the invention, the pedestrian node N1 periodically executes the following operations:

step 201: starting;

step 202: the pedestrian node N1 constructs an address, the coordinate of the address is the current coordinate of the pedestrian node N1, the hardware ID is the telephone number of the pedestrian node N1, the pedestrian node N1 sends a neighbor message from the interface W0, the message type value of the neighbor message is 1, the angular color value is 2, and the address is the constructed address;

step 203: if the pedestrian node receives the neighbor message from the interface W0, step 204 is executed, otherwise step 205 is executed;

step 204: the pedestrian node receiving the neighbor message from the interface W0 checks the neighbor table, if a neighbor table entry exists and the hardware ID of the address of the neighbor table entry is equal to the hardware ID of the address of the neighbor message, the address of the neighbor table entry is updated to the address of the neighbor message, the interface domain value is updated to the interface W0, the life cycle is set to the maximum value, otherwise, the pedestrian node creates a neighbor table entry, the address of the neighbor table entry is equal to the address of the neighbor message, the interface domain value is the interface W0, and the life cycle is set to the maximum value; step 208 is executed;

step 205: after the access node receives the neighbor message from the interface W3 or the vehicle node receives the neighbor message from the interface W1, the role value of the neighbor message is checked, if the role value is equal to 0 or 1, step 207 is executed, otherwise step 206 is executed;

step 206: the access node that received the neighbor message from W3 or the vehicle node that received the neighbor message from interface W1 looks at the neighbor table; if a neighbor table entry exists, the hardware ID of the address of the neighbor table entry is equal to the hardware ID of the address of the neighbor message, the address of the neighbor table entry is updated to the address of the neighbor message, if the access node receives the neighbor message from W3, the interface domain value is updated to interface W3, otherwise, the interface domain value is updated to interface W1, the life cycle is set to the maximum value, if the neighbor table entry does not exist, the access node or the vehicle node creates a neighbor table entry, the address of the neighbor table entry is equal to the address of the neighbor message, if the access node receives the neighbor message from W3, the interface domain value is interface W4, otherwise, the interface domain value is set to interface W1, and the life cycle is set to the maximum value;

step 207: the access node receives the neighbor message from the interface W4 or the vehicle node receives the neighbor message from the interface W2 and then checks the neighbor table, if a neighbor table entry exists, the hardware ID of the address of the neighbor table entry is equal to the hardware ID of the address of the neighbor message, the address of the neighbor table entry is updated to the address of the neighbor message, if the access node receives the neighbor message from the interface W4, the interface domain value is updated to the interface W4, otherwise, the interface domain value is updated to the interface W2, and the life cycle is set to the maximum value; if the neighbor table entry does not exist, the access node or the vehicle node creates a neighbor table entry, the address of the neighbor table entry is equal to the address of the neighbor message, if the access node receives the neighbor message from the interface W4, the interface domain value is set to be the interface W4, otherwise, the interface domain value is set to be the interface W2, and the life cycle is set to be the maximum value;

step 208: and (6) ending.

The pedestrian node establishes the neighbor table through the process, so that the real-time coordinate and the telephone number of the pedestrian node can be obtained through the address of the neighbor table, whether the pedestrian node has the condition of small distance with the adjacent vehicle node or the pedestrian node or not is judged, and the traffic accident is effectively avoided.

In the method of the present invention, the access node AP1 periodically performs the following operations:

step 301: starting;

step 302: the access node AP1 constructs an address, the coordinate of the address is the current coordinate of the access node AP1, and the hardware ID is the MAC address of the access node AP 1; the access node AP1 sends a neighbor message from the interface W3 and the interface W4 respectively, wherein the message type value of the neighbor message is 1, the angle value is 0, and the address is a constructed address;

step 303: if the pedestrian node receives the neighbor message from the interface W0, step 304 is executed, otherwise step 305 is executed;

step 304: the pedestrian node that receives the neighbor message from the interface W0 looks at the neighbor table; if a neighbor table entry exists, the hardware ID of the address of the neighbor table entry is equal to the hardware ID of the address of the neighbor message, the address of the neighbor table entry is updated to the address of the neighbor message, the interface domain value is updated to the interface W0, and the life cycle is set to be the maximum value; otherwise, the pedestrian node creates a neighbor table entry, the address of the neighbor table entry is equal to the address of the neighbor message, the interface domain value is interface W0, the life cycle is set to the maximum value, and step 308 is executed;

step 305: after the access node receives the neighbor message from the interface W4 or the vehicle node receives the neighbor message from the interface W2, the role value of the neighbor message is checked, if the role value is equal to 0 or 1, step 306 is executed, otherwise step 307 is executed;

step 306: the access node that received the neighbor message from the interface W4 or the vehicle node that received the neighbor message from the interface W2 looks at the neighbor table; if a neighbor table entry exists, the hardware ID of the address of the neighbor table entry is equal to the hardware ID of the address of the neighbor message, the address of the neighbor table entry is updated to the address of the neighbor message, if the access node receives the neighbor message from W4, the interface domain value is updated to interface W4, otherwise, the interface domain value is updated to interface W2, the life cycle is set to the maximum value, if the neighbor table entry does not exist, the access node or the vehicle node creates a neighbor table entry, the address of the neighbor table entry is equal to the address of the neighbor message, if the access node receives the neighbor message from W4, the interface domain value is interface W4, otherwise, the interface domain value is set to interface W2, and the life cycle is set to the maximum value;

step 307: the access node receives the neighbor message from the interface W3 or the vehicle node receives the neighbor message from the interface W1 and then checks the neighbor table, if a neighbor table entry exists, the hardware ID of the address of the neighbor table entry is equal to the hardware ID of the address of the neighbor message, the address of the neighbor table entry is updated to the address of the neighbor message, if the access node receives the neighbor message from the interface W3, the interface domain value is updated to the interface W3, otherwise, the interface domain value is updated to the interface W1, and the life cycle is set to the maximum value; if the neighbor table entry does not exist, the access node or the vehicle node creates a neighbor table entry, the address of the neighbor table entry is equal to the address of the neighbor message, if the access node receives the neighbor message from the interface W3, the interface domain value is set to be the interface W3, otherwise, the interface domain value is set to be the interface W1, and the life cycle is set to be the maximum value;

step 308: and (6) ending.

The access node establishes the neighbor table through the process, so that the access node can acquire the real-time coordinates of the neighbor vehicle nodes or the pedestrian nodes through the addresses in the neighbor table, and further judge whether the distance between the adjacent pedestrian nodes or the adjacent vehicle nodes is smaller, and further effectively avoid traffic accidents.

In the method of the invention, each access node stores an equipment list, and each equipment list comprises an address and a life cycle;

the device message contains a message type, a final address, a destination address and a source address;

among all the access nodes, if the device D1 is closest to the access node AP1, the device D1 periodically performs the following operations:

step 401: starting;

step 402: the device D1 constructs an address A1 and an address A2, if the device D1 is a vehicle node, the coordinates of the address A1 are the current coordinates of the device D1, the hardware ID is the license plate number of the device D1, if the device D1 is not a vehicle node, the coordinates of the address A1 are the current coordinates of the device D1, and the hardware ID is the telephone number of the device D1; in the address A2, the coordinate is the coordinate of the access node AP1, and the hardware ID is the MAC address of the access node AP 1; the device D1 constructs a device message, the message type value of the device message is 2, the source address is the address A1, and the final address is the address A2; the device D1 checks the neighbor table, if there is a neighbor table entry whose address is equal to the address a2, then step 403 is executed, otherwise step 404 is executed;

step 403: the device D1 selects a neighbor table entry with an address equal to the address a2, sets the destination address of the device message as the address of the neighbor table entry, sends the device message from the interface of the neighbor table entry, and executes step 405;

step 404: the device D1 selects a neighbor table entry, the coordinate of the address of the neighbor table entry is closest to the coordinate of the final address of the constructed device message, the destination address of the device message is set as the address of the neighbor table entry, and the device message is sent from the interface of the neighbor table entry;

step 405: if the access node AP1 receives the device message, then step 410 is performed, otherwise step 406 is performed;

step 406: the device receiving the device message checks whether the hardware ID of the device is equal to the hardware ID of the destination address of the device message, if so, the step 407 is executed, otherwise, the step 410 is executed;

step 407: the device receiving the device message checks the neighbor table, if a neighbor table entry exists, the address of the neighbor table entry is equal to the final address of the device message, step 408 is executed, otherwise, step 409 is executed;

step 408: the device receiving the device message selects a neighbor table entry, the address of the neighbor table entry is equal to the final address of the device message, the destination address of the device message is set as the address of the neighbor table entry, the device message is sent from the interface of the neighbor table entry, and step 405 is executed;

step 409: the device receiving the device message selects a neighbor table entry, the coordinate of the address of the neighbor table entry is closest to the coordinate of the final address of the device message, the destination address of the device message is set as the address of the neighbor table entry, the device message is sent from the interface of the neighbor table entry, and step 405 is executed;

step 410: the access node AP1 checks the device table after receiving the device message; if an equipment list item exists, the hardware ID of the address of the equipment list item is equal to the hardware ID of the source address of the equipment message, the address of the equipment list item is updated to the source address of the equipment message, and the life cycle is set to be the maximum value; otherwise, the access node AP1 creates a device table entry whose address is equal to the source address of the device message and whose life cycle is set to the maximum value;

step 411: and (6) ending.

The access node establishes the equipment table through the process, so that the access node can acquire the real-time coordinates of the vehicle node or the pedestrian node through the address in the equipment table, and an optimal routing path reaching the target vehicle node or the pedestrian node is established, so that the alarm message is quickly sent to effectively avoid traffic accidents.

In the method, a path from an access node to a device is represented by an address set, and the address set is composed of addresses of vehicle nodes or pedestrian nodes contained in the path;

if the hardware ID of the device D1 is HID1, among all access nodes, the device D1 is closest to the access node AP 1; the access node AP1 obtains the set of addresses to reach device D1 by:

step 501: starting;

step 502: the access node AP1 acquires the communication radius R by using a formula (1), and sets an address set parameter as1, wherein the initial value of the address set parameter as1 is null; the access node AP1 selects a device table entry E1, and the hardware ID of the device table entry E1 address is equal to HID 1; if the distance between the coordinates of the access node AP1 and the coordinates of the device table entry E1 address is smaller than the communication radius R, executing step 506, otherwise executing step 503;

step 503: the access node AP1 selects an equipment table entry E2, the distance between the coordinate of the equipment table entry E2 address and the coordinate of the access node AP1 is smaller than the transmission radius R, the distance between the coordinate of the equipment table entry E2 address and the coordinate of the equipment table entry E1 address is minimum, and the address of the equipment table entry E2 is added into the address set parameter as1 and serves as the last element;

step 504: the access node AP1 selects a device table entry E3, the hardware ID of the address of the device table entry E3 is equal to the last element of the address set parameter as 1; if the distance between the coordinates of the device table entry E3 address and the coordinates of the device table entry E1 address is smaller than the communication radius R, executing the step 506, otherwise executing the step 505;

step 505: the access node AP1 selects an equipment table entry E4, the distance between the coordinate of the equipment table entry E4 address and the coordinate of the equipment table entry E3 address is smaller than the transmission radius R, the distance between the coordinate of the equipment table entry E4 address and the coordinate of the equipment table entry E1 address is minimum, and the address of the equipment table entry E4 is added into the address set parameter as1 and serves as the last element; step 504 is executed;

step 506: the access node AP1 adds the address of the device table entry E1 to the address set parameter as1 as the last element;

step 507: and (6) ending.

The access node establishes the optimal routing path to the destination device through the process, and the process acquires the real-time coordinate of the device through the address in the device table, so that the optimal routing path to the destination device is established, and the alarm message is quickly sent to effectively avoid the occurrence of the traffic accident.

In the method of the invention, a local early warning message comprises a message type, a destination address and a source address; device D1 periodically performs the following operations:

step 601: starting;

step 602: device D1 looks at the neighbor table, and for each neighbor table entry, device D1 performs the following operations: the device D1 checks whether the distance between the current coordinate of the device D1 and the coordinate of the neighbor table entry address is greater than a threshold TH1, for example, 5-10 meters, if so, the device D1 does not perform any operation, otherwise, the device D1 constructs an address, if the device D1 is a vehicle node, the coordinate of the address is the current coordinate of the device D1, the hardware ID is the license plate number of the device D1, if the device D1 is a pedestrian node, the coordinate of the address is the current coordinate of the device D1, and the hardware ID is the phone number of the device D1; the device D1 sends a local warning message through the interface of the neighbor table entry, where the message type value in the local warning message is 3, the destination address is the address of the neighbor table entry, and the source address is the created address;

step 603: if the access node receives the local early warning message, executing step 606, otherwise executing step 604;

step 604: after receiving the local early warning message, the device judges whether the address of the device is equal to the destination address of the local early warning message, if so, the step 605 is executed, otherwise, the step 606 is executed;

step 605: the equipment receiving the local early warning message stores the source address in the local early warning message;

step 606: and (6) ending.

The device realizes local safety alarm through the process, and the device acquires real-time coordinates of the neighbor vehicle nodes or the pedestrian nodes through the addresses in the neighbor table so as to judge whether the distance between the device and the adjacent pedestrian nodes or the adjacent vehicle nodes is smaller than a critical value, and if the distance between the device and the adjacent vehicle nodes is smaller than the critical value, the device sends local early warning information to the adjacent pedestrian nodes or the adjacent vehicle nodes so as to effectively avoid traffic accidents.

In the method of the invention, a remote early warning message comprises a message type, an address set and a load; the access node AP1 periodically performs the following operations:

step 701: starting;

step 702: the access node AP1 checks the equipment table, and sets an early warning identification parameter p1, wherein the initial value of the early warning identification parameter p1 is 0; for each device table entry T1, the access node AP1 performs the following: the access node AP1 selects all device table entries that meet condition 1: if the number of the device table entries meeting the condition 1 is 0, no operation is executed, otherwise, the access node AP1 sets the early warning identification parameter p1 to 1, and executes

step

501 and 507 to calculate an address set parameter as1, where the address set parameter as1 represents a path from the access node AP1 to the target device, and the hardware ID of the target device is equal to the hardware ID of the address of the device table entry T1; the access node AP1 constructs a remote early warning message, the message type value of the remote early warning message is 4, the address set is a parameter as1, and the load is the equipment table item meeting the condition 1; the access node AP1 selects a neighbor table entry whose address is equal to the first element in the remote early warning message address set, and forwards the remote early warning message from the interface of the neighbor table entry;

condition 1: the device table entry is not equal to the device table entry T1, and the distance between the coordinate of the address of the device table entry T1 and the coordinate of the address of the device table entry is less than the threshold TH 1;

step 703: if the early warning identification parameter p1 is 0, executing step 708, otherwise executing step 704;

step 704: after receiving the remote early warning message, the device determines whether its address is equal to the first element in the remote early warning message address set, if so, executes step 705, otherwise executes step 708;

step 705: the device receiving the remote early warning message deletes the first element from the remote early warning message address set, if the remote early warning message address set is empty, step 707 is executed, otherwise step 706 is executed;

step 706: the device receiving the remote early warning message selects a neighbor table entry, the address of which is equal to the first element in the remote early warning message address set, forwards the remote early warning message from the interface of the neighbor table entry, and executes step 704;

step 707: the equipment receiving the remote early warning message stores the equipment list item in the remote early warning message load;

step 708: and (6) ending.

The access node realizes remote safety alarm through the process, acquires the real-time coordinates of the vehicle node or the pedestrian node through the address in the equipment table so as to judge whether the distance between the access node and the adjacent pedestrian node or the adjacent vehicle node is smaller than a critical value, and if the distance between the access node and the adjacent pedestrian node or the adjacent vehicle node is smaller than the critical value, the access node sends a remote early warning message to the pedestrian node or the vehicle node so as to effectively avoid traffic accidents.

Has the advantages that: the invention provides a method for realizing a safety alarm system based on the Internet of vehicles, a vehicle node can quickly acquire service data through the method provided by the invention, the delay and the cost for acquiring the service data are reduced, and the invention realizes safety alarm so as to effectively avoid traffic accidents, thereby having wide application prospect.

Drawings

The foregoing and/or other advantages of the invention will become further apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings.

FIG. 1 is a schematic diagram illustrating a process for establishing a neighbor list by a vehicle node according to the present invention.

Fig. 2 is a schematic flow chart of a pedestrian node neighbor table establishment process according to the present invention.

Fig. 3 is a schematic diagram of a flow of establishing a neighbor table by an access node according to the present invention.

Fig. 4 is a flow chart of the device table establishment according to the present invention.

Fig. 5 is a schematic diagram of a path establishment process according to the present invention.

Fig. 6 is a schematic view of a local early warning process according to the present invention.

Fig. 7 is a schematic diagram of a remote early warning process according to the present invention.

The specific implementation mode is as follows:

the invention provides a method for realizing a safety alarm system based on the Internet of vehicles, a vehicle node can quickly acquire service data through the method provided by the invention, the delay and the cost for acquiring the service data are reduced, and the invention realizes safety alarm so as to effectively avoid traffic accidents, thereby having wide application prospect.

FIG. 1 is a schematic diagram illustrating a process for establishing a neighbor list by a vehicle node according to the present invention. The Internet of vehicles consists of equipment and access nodes; the device comprises a pedestrian node and a vehicle node; the pedestrian node is an intelligent device which contains a mobile phone number and can carry out data communication; for example, a person walking on the roadside and carrying a smart device, including a cell phone, etc.;

a pedestrian node is provided with an interface W0;

each access node has unique coordinates;

a device obtains the coordinates of each access node through an electronic map;

value of message type	Message name
		1	Neighbor messages
2	Device messages
		3	Local early warning message
4	Remote early warning message

the vehicle node V1 periodically performs the following operations:

step 101: starting;

step 108: and (6) ending.

Fig. 2 is a schematic flow chart of a pedestrian node neighbor table establishment process according to the present invention. The pedestrian node N1 periodically performs the following operations:

step 201: starting;

step 208: and (6) ending.

Fig. 3 is a schematic diagram of a flow of establishing a neighbor table by an access node according to the present invention. The access node AP1 periodically performs the following operations:

step 301: starting;

step 308: and (6) ending.

Fig. 4 is a flow chart of the device table establishment according to the present invention. Each access node stores an equipment list, and each equipment list item comprises an address and a life cycle;

step 401: starting;

step 411: and (6) ending.

Fig. 5 is a schematic diagram of a path establishment process according to the present invention. The path from the access node to a device is represented by an address set, and the address set is composed of the addresses of vehicle nodes or pedestrian nodes contained in the path;

step 501: starting;

step 507: and (6) ending.

Fig. 6 is a schematic view of a local early warning process according to the present invention. A local early warning message contains a message type, a destination address and a source address; device D1 periodically performs the following operations:

step 601: starting;

step 606: and (6) ending.

Fig. 7 is a schematic diagram of a remote early warning process according to the present invention. A remote early warning message contains a message type, an address set and a load; the access node AP1 periodically performs the following operations:

step 701: starting;

step

step 708: and (6) ending.

Example 1

Based on the simulation parameters in table 1, this embodiment simulates a method for implementing a security alarm system based on internet of vehicles in the present invention, after the network is started, each vehicle node periodically executes

step

101 and 108 to establish a neighbor table, and the real-time coordinates and license plate numbers of the neighbor vehicle nodes can be obtained through the addresses of the vehicle nodes, and whether there is a situation where the distance between the neighboring vehicle nodes is small is determined, where the distance is set according to the traffic conditions of different countries and different areas, and the distance is set to a default value of a safe distance of 20m, so as to effectively avoid traffic accidents, for example, the addresses of the neighbor list items related to the vehicle nodes established by pedestrian nodes are (120, 31)/three 99999 (simulated license plate numbers), the interface is W0, the life cycle is 1s, the addresses of the neighbor list items related to the vehicle nodes established by access nodes are (120,31) the address of the neighbor table entry related to the vehicle node established by the vehicle node is (120, 31)/SuE 99999, the interface is W2, and the life cycle is 1 s. After the network is started, each pedestrian node periodically executes step 201 and step 208 to establish a neighbor table, the frequency for establishing the neighbor table is set according to the network stability of different countries and different regions, the frequency for establishing the neighbor table is set to 10/s, the real-time coordinate and telephone number of the pedestrian node can be obtained through the address of the pedestrian node, whether the distance between the adjacent vehicle node and the pedestrian node is smaller is judged, the distance is set according to the traffic road condition of different countries and different regions, the distance is set to a safety distance default value of 20m, and thus traffic accidents are effectively avoided, for example, the address of a neighbor table item related to the pedestrian node established by the pedestrian node is (140,51)/18900000001, the interface is W0, the life cycle is 1s, the address of a neighbor table item related to the pedestrian node established by the access node is (140,51) 18900000001, the interface is W3, the life cycle is 1s, the address of the neighbor table entry related to the pedestrian node established by the vehicle node is (140,51)/18900000001, the interface is W1, and the life cycle is 1 s. After the network is started, each access node periodically executes step 301 and step 308 to establish a neighbor table, the frequency for establishing the neighbor table is set according to the network stability of different countries and different regions, the frequency for establishing the neighbor table is set to 10/s, the access node can acquire the real-time coordinates of the neighbor vehicle nodes or the pedestrian nodes through the addresses in the neighbor table, so as to judge whether the distance between the adjacent pedestrian nodes or the adjacent vehicle nodes is smaller, the distance is set according to the traffic road conditions of different countries and different regions, the distance is set to a safe distance default value of 20m, so as to effectively avoid traffic accidents, for example, the addresses of the neighbor table entries related to the access node established by the pedestrian node are (180,90)/000A:000B:000C, the interface is W0, the life cycle is 1s, the addresses of the neighbor table entries related to the access node established by the vehicle node are (180,90) the interface is W0, the life cycle is 1 s. Then, each vehicle node or pedestrian node executes

step

401 and 411 so that the access node can establish a device table, so that the access node can obtain real-time coordinates of the vehicle node or pedestrian node through addresses in the device table, thereby establishing an optimal routing path to the destination vehicle node or pedestrian node to quickly send an alarm message to effectively avoid occurrence of a traffic accident, for example, the address in the device table entry corresponding to the vehicle node is (120, 31)/threo E99999, the lifetime is 1s, the address in the device table entry corresponding to the pedestrian node is (140,51)/18900000001, and the lifetime is 1 s. After the access node establishes the device table, it establishes the optimal routing path to the destination device by performing

step

501 and 507, and the optimal routing path is stored in the address set parameter as1, for example, the access node establishes that the address set parameter as1 to the vehicle node with address (120, 31)/threo E99999 is { (118, 31)/threo E11111, (119, 31)/threo E66666, (120, 31)/threo E99999 }. After each device establishes a neighbor table, the

step

601 and 606 are periodically executed to realize local early warning to avoid car accidents, if the device detects that the distance between the device and the neighbor device is less than an early warning value, the early warning value is set according to traffic road conditions of different countries and different regions, the invention sets the distance as a default value of safe distance of 20m, and then the local early warning message is sent to the neighbor device, so that the neighbor device can obtain a mobile phone number or a license plate number of the device needing attention through the source address of the local early warning message. Each access node periodically executes steps 701-708 to implement remote early warning to avoid car accidents, that is, if the access node detects that the distance between one device and a neighboring device is less than an early warning value, the access node sends a remote early warning message to the device through an optimal routing path, so that the device can obtain the address of the device needing attention through the device table entry in the remote early warning message load to avoid car accidents.

The performance analysis was as follows: in the process of local early warning, the success rate of receiving the local early warning message by the target device is 99.7%, and the packet loss rate generated by the wireless link due to unsuccessful reasons is 99% because the access node adopts the optimal routing path to send the remote early warning message in the process of remote early warning.

TABLE 1 simulation parameters

The invention provides a method for implementing a safety alarm system based on internet of vehicles, and a plurality of methods and ways for implementing the technical scheme, and the above description is only a preferred embodiment of the invention, and it should be noted that, for those skilled in the art, a plurality of improvements and embellishments can be made without departing from the principle of the invention, and these improvements and embellishments should also be regarded as the protection scope of the invention. The components not specified in this embodiment can be implemented by the prior art.

Claims

1. The implementation method of the security alarm system based on the Internet of vehicles is characterized in that the Internet of vehicles is composed of equipment and access nodes; the device comprises a pedestrian node and a vehicle node; the pedestrian node is an intelligent device which contains a mobile phone number and can carry out data communication;

each access node is provided with an interface W3 and an interface W4, wherein the interface W3 is used for communicating with a pedestrian node, and the interface W4 is used for communicating with a vehicle node or an access node;

a pedestrian node is provided with an interface W0;

the communication radius of the interface W0, the interface W1 and the interface W3 is R1, and the communication radius of the interface W2 and the interface W4 is R2;

each access node has unique coordinates;

a device obtains the coordinates of each access node through an electronic map;

the vehicle node V1 periodically performs the following operations:

step 101: starting;

step 108: and (6) ending.

2. The implementation method of the internet of vehicles-based safety alarm system according to claim 1, wherein the pedestrian node N1 periodically performs the following operations:

step 201: starting;

step 208: and (6) ending.

3. The method for implementing the security alarm system based on the internet of vehicles as claimed in claim 2, wherein the access node AP1 periodically performs the following operations:

step 301: starting;

step 308: and (6) ending.

4. The method for implementing the security alarm system based on the Internet of vehicles as claimed in claim 3, wherein each access node stores a device table, each device table entry contains an address and a life cycle;

step 401: starting;

step 411: and (6) ending.

5. The method for implementing the safety alarm system based on the internet of vehicles as claimed in claim 1, wherein the path from the access node to a device is represented by an address set, and the address set is composed of the addresses of the vehicle nodes or the pedestrian nodes contained in the path;

step 501: starting;

step 507: and (6) ending.

6. The method for implementing the safety alarm system based on the internet of vehicles as claimed in claim 5, wherein a local early warning message comprises a message type, a destination address and a source address; device D1 periodically performs the following operations:

step 601: starting;

step 602: device D1 looks at the neighbor table, and for each neighbor table entry, device D1 performs the following operations: the device D1 checks whether the distance between the current coordinate of the device D1 and the coordinate of the neighbor table entry address is larger than a threshold TH1, if so, the device D1 does not execute any operation, otherwise, the device D1 constructs an address, if the device D1 is a vehicle node, the coordinate of the address is the current coordinate of the device D1, the hardware ID is the license plate number of the device D1, if the device D1 is a pedestrian node, the coordinate of the address is the current coordinate of the device D1, and the hardware ID is the telephone number of the device D1; the device D1 sends a local warning message through the interface of the neighbor table entry, where the message type value in the local warning message is 3, the destination address is the address of the neighbor table entry, and the source address is the created address;

step 606: and (6) ending.

7. The method for implementing the safety alarm system based on the Internet of vehicles as claimed in claim 6, wherein a remote early warning message comprises a message type, an address set and a load; the access node AP1 periodically performs the following operations:

step 701: starting;

step 702: the access node AP1 checks the equipment table, and sets an early warning identification parameter p1, wherein the initial value of the early warning identification parameter p1 is 0; for each device table entry T1, the access node AP1 performs the following: the access node AP1 selects all device table entries that meet condition 1: if the number of the device table entries meeting the condition 1 is 0, no operation is executed, otherwise, the access node AP1 sets the early warning identification parameter p1 to 1, and executes step 501 and 507 to calculate an address set parameter as1, where the address set parameter as1 represents a path from the access node AP1 to the target device, and the hardware ID of the target device is equal to the hardware ID of the address of the device table entry T1; the access node AP1 constructs a remote early warning message, the message type value of the remote early warning message is 4, the address set is a parameter as1, and the load is the equipment table item meeting the condition 1; the access node AP1 selects a neighbor table entry whose address is equal to the first element in the remote early warning message address set, and forwards the remote early warning message from the interface of the neighbor table entry;

step 708: and (6) ending.