CN113781819A - Vehicle-road cooperative vehicle positioning system and method for realizing simultaneous positioning of multiple vehicles - Google Patents

Vehicle-road cooperative vehicle positioning system and method for realizing simultaneous positioning of multiple vehicles Download PDF

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CN113781819A
CN113781819A CN202110883855.3A CN202110883855A CN113781819A CN 113781819 A CN113781819 A CN 113781819A CN 202110883855 A CN202110883855 A CN 202110883855A CN 113781819 A CN113781819 A CN 113781819A
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vehicle
information
positioning
positioning information
roadside
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乔智杰
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Shenzhen Zhicheng Technology Co ltd
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Shenzhen Zhicheng Technology Co ltd
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    • G—PHYSICS
    • G08—SIGNALLING
    • G08G—TRAFFIC CONTROL SYSTEMS
    • G08G1/00—Traffic control systems for road vehicles
    • G08G1/123—Traffic control systems for road vehicles indicating the position of vehicles, e.g. scheduled vehicles; Managing passenger vehicles circulating according to a fixed timetable, e.g. buses, trains, trams
    • G—PHYSICS
    • G08—SIGNALLING
    • G08G—TRAFFIC CONTROL SYSTEMS
    • G08G1/00—Traffic control systems for road vehicles
    • G08G1/01—Detecting movement of traffic to be counted or controlled
    • G08G1/0104—Measuring and analyzing of parameters relative to traffic conditions
    • G08G1/0108—Measuring and analyzing of parameters relative to traffic conditions based on the source of data
    • G08G1/0116—Measuring and analyzing of parameters relative to traffic conditions based on the source of data from roadside infrastructure, e.g. beacons
    • G—PHYSICS
    • G08—SIGNALLING
    • G08G—TRAFFIC CONTROL SYSTEMS
    • G08G1/00—Traffic control systems for road vehicles
    • G08G1/01—Detecting movement of traffic to be counted or controlled
    • G08G1/017—Detecting movement of traffic to be counted or controlled identifying vehicles
    • G08G1/0175—Detecting movement of traffic to be counted or controlled identifying vehicles by photographing vehicles, e.g. when violating traffic rules
    • G—PHYSICS
    • G08—SIGNALLING
    • G08G—TRAFFIC CONTROL SYSTEMS
    • G08G1/00—Traffic control systems for road vehicles
    • G08G1/01—Detecting movement of traffic to be counted or controlled
    • G08G1/04—Detecting movement of traffic to be counted or controlled using optical or ultrasonic detectors
    • G—PHYSICS
    • G08—SIGNALLING
    • G08G—TRAFFIC CONTROL SYSTEMS
    • G08G1/00—Traffic control systems for road vehicles
    • G08G1/01—Detecting movement of traffic to be counted or controlled
    • G08G1/042—Detecting movement of traffic to be counted or controlled using inductive or magnetic detectors
    • G—PHYSICS
    • G08—SIGNALLING
    • G08G—TRAFFIC CONTROL SYSTEMS
    • G08G1/00—Traffic control systems for road vehicles
    • G08G1/01—Detecting movement of traffic to be counted or controlled
    • G08G1/052—Detecting movement of traffic to be counted or controlled with provision for determining speed or overspeed

Abstract

The invention discloses a vehicle-road cooperative vehicle positioning system and a method for realizing simultaneous positioning of multiple vehicles, wherein the identity of a vehicle is obtained by comparing first positioning information and second positioning information which are simultaneously obtained in an overlapping area, so that the vehicle identity information is transmitted from a vehicle-mounted system to a road side system, and the road side system can send vehicle positioning information with vehicle identity information.

Description

Vehicle-road cooperative vehicle positioning system and method for realizing simultaneous positioning of multiple vehicles
Technical Field
The invention relates to a vehicle-road cooperative vehicle positioning system and method, in particular to a vehicle-road cooperative vehicle positioning system and method for realizing simultaneous positioning of multiple vehicles.
Background
At present, vehicles are positioned by global navigation satellite systems (GNS) such as Global Positioning System (GPS) and Beidou. However, in areas with weak or no GNSS signals, such as tunnels, the satellite navigation devices, such as GPS and beidou, cannot work, and thus global continuous positioning cannot be provided.
To address this problem, inertial navigation is currently used to locate the vehicle in the tunnel. However, inertial navigation has two problems, namely the problem of long-term drift, namely the inherent drift rate of inertial components causes the positioning error to gradually increase along with the accumulation of time. Another problem is that it is expensive. The price of the currently prevailing IMU on the market, which is capable of providing lane-level positioning within 10 seconds after GNSS signal loss, is around 20 ten thousand dollars. For example, a hundred-degree APOLLO autonomous vehicle may use a NovAtel inertial navigation device that costs approximately 20-25 ten thousand dollars (see: [1] http:// www.360doc.com/content/19/1021/11/66850528_868133210.shtml, [2] http:// www.360doc15.net/wxarticleene/858667603. html). Therefore, inertial navigation cannot meet the positioning requirements of the vehicle in the tunnel in terms of performance and price.
Chinese patent document CN208953695U "location system for autonomous vehicles and location management system" proposes a vehicle-road cooperative vehicle location system, which consists of a road side system and a vehicle-mounted system, wherein the road side system consists of a vehicle information measurement unit, a processor and a road side wireless communication device; the vehicle-mounted system is a vehicle-mounted wireless communication device. The vehicle information measuring unit is generally a sensing device such as a radar or a camera that can measure vehicle motion information. The processor is a computational unit with computational capabilities. Roadside wireless communication devices are typically communication units for V2X signals. The vehicle-mounted wireless communication device is generally a communication unit of a V2X signal corresponding to the roadside wireless communication device, and can communicate with the roadside wireless communication device.
When the system works, the vehicle information measuring unit on the road side measures the motion information of the vehicle, the motion information is processed by the processor to obtain the positioning information of the vehicle, the measured positioning information is sent out in a wireless information mode through the wireless communication device on the road side, the vehicle-mounted wireless communication device receives the wireless information, and the vehicle can obtain the positioning information of the vehicle after the steps of decoding and the like.
However, such a vehicle-road cooperative vehicle positioning system can only realize positioning of a single vehicle, and cannot realize simultaneous positioning of multiple vehicles. When a plurality of vehicles (not less than 2) need to be positioned at the same time, the roadside vehicle information measurement unit cannot acquire the vehicle identity information, so that the wireless information communicated by the roadside wireless communication device and the vehicle-mounted wireless communication device does not contain the vehicle identity information, and the vehicle cannot analyze the positioning information of the vehicle.
Disclosure of Invention
In order to make up for the defects of the prior art, the invention provides a vehicle-road cooperative vehicle positioning system and method for realizing simultaneous positioning of multiple vehicles.
The technical problem of the invention is solved by the following technical scheme:
a vehicle-road cooperative vehicle positioning method comprises the following steps: s1, obtaining first positioning information of the vehicle, which is measured in an overlapping area of a first positioning system and a second positioning system, wherein the first positioning information of the vehicle is measured by a first positioning system on a vehicle-mounted system; the system is communicated with a road side system to realize assignment and correspondence of vehicle identity information of the same vehicle with the road side system, so that second combined information sent by a subsequent road side system in a broadcasting mode can contain the vehicle identity information subjected to assignment and correspondence and second positioning information corresponding to the vehicle; when the number of vehicles is not less than 2, the plurality of second combined information form a second combined information sequence; and S2, when the positioning is required to be carried out through the second positioning system, repeatedly receiving a second combined information sequence sent by the road side system through a broadcasting mode, extracting the vehicle identity information in the second combined information sequence, and when the extracted identity information is consistent with the identity information of the vehicle, determining that the second positioning information corresponding to the identity information contained in the second combined information is the second positioning information of the vehicle measured by the road side system.
In some embodiments, the following technical features are also included:
in step S1, the vehicle identification information is identification information unique to the vehicle or vehicle identification information temporarily distributed by the road side system; the method for realizing the assignment and the correspondence of the vehicle identity information by the vehicle-mounted system and the road side system through the communication with the road side system comprises at least one of the following steps:
the method comprises the following steps: combining the first positioning information and the vehicle identity information to form first combined information which is sent out by a wireless signal, so that a road side system can execute the following steps: respectively comparing the first positioning information in the first combined information with second positioning information in a second positioning information sequence of the vehicle at the same time period, which is measured by a road side system, and extracting vehicle identity information in the first combined information when the comparison is successful, wherein the vehicle identity information is the vehicle identity information for realizing assignment correspondence of the vehicle-mounted system and the road side system;
the second method comprises the following steps: and receiving a second combined information sequence sent by the road side system in a broadcasting mode, extracting second positioning information of the vehicle measured by the road side system contained in the second combined information and vehicle identity information temporarily distributed to the vehicle by the road side system corresponding to the second positioning information, and when the extracted second positioning information is consistent with the first positioning information of the vehicle obtained from the first positioning system by the vehicle, extracting corresponding identity information as the identity information of the vehicle, namely the vehicle identity information assigned and corresponding by the vehicle-mounted system and the road side system.
And step S3, at least when the first positioning information is not available, the second positioning information is used as the self positioning information of the vehicle to realize continuous navigation or automatic driving.
The first combined information also comprises real-time clock information.
The first positioning information includes vehicle position information and vehicle speed information.
Also comprises the following steps: s4, receiving relocation request information from a road side system; s5, reading a vehicle historical first positioning information sequence in an overlapping area stored in a vehicle-mounted memory, framing the first positioning information sequence and vehicle identity information, and sending the first positioning information sequence and the vehicle identity information to a roadside system; the framing comprises historical time information, vehicle positioning information corresponding to the historical time and self vehicle identity information; so that the road side can realize the re-matching of the vehicle identity information and the vehicle positioning information.
Also comprises the following steps: s5', sending a relocation request command in a wireless mode; s6', receiving historical second positioning information sequences and corresponding vehicle identity information sequences of different vehicles in the overlapping region stored in a road side memory which is sent by framing of a road side system; s7', decoding the frame to obtain an identity information sequence and a corresponding vehicle history second positioning information sequence; s8', reading the vehicle history first positioning information sequence in the overlapping area stored in the vehicle-mounted memory, comparing with the received vehicle history second positioning information sequence of different vehicles, judging as the vehicle when finding the consistent person, and determining the vehicle identity information in the overlapping area of the vehicle.
The invention also provides a method for generating and sending the vehicle-road cooperative vehicle positioning signal, which comprises the following steps: a1, obtaining second positioning information of the vehicle measured in an overlapping area of the first positioning system and the second positioning system, wherein the second positioning information of the vehicle is measured by a second positioning system on the road side; the system is communicated with a vehicle-mounted system to realize the assignment and the correspondence of the vehicle identity information of the same vehicle with the vehicle-mounted system; a2, sending second combined information in a broadcast mode, wherein the second combined information comprises vehicle identity information corresponding to the assignment and second positioning information corresponding to the vehicle; when the vehicle is not less than 2, the plurality of second combined information forms a second combined information sequence.
In some embodiments, the following features are also included:
the first positioning information is obtained by extracting from received first combined information sent by a vehicle-mounted system in a wireless signal mode;
the vehicle identity information is inherent identity information of a vehicle or temporarily distributed by a road side system;
the step a1 is performed with a vehicle-mounted system, and the method for implementing assignment and correspondence of vehicle identity information by the vehicle-mounted system and the road side system includes at least one of the following steps:
the method comprises the following steps: receiving first combined information sent by a vehicle-mounted system through a wireless signal, wherein the first combined information comprises first positioning information and vehicle identity information, respectively comparing the first positioning information in the first combined information with second positioning information in a vehicle second positioning information sequence of the same time period measured by a road side system, and extracting the vehicle identity information in the first combined information when the comparison is successful, namely the vehicle identity information for realizing assignment correspondence of the vehicle-mounted system and the road side system; the second method comprises the following steps: sending a second combined information sequence in a broadcasting mode, wherein the second combined information comprises second positioning information of the vehicle measured by the road side system and vehicle identity information temporarily distributed to the vehicle by the road side system corresponding to the second positioning information; and when the second positioning information extracted by the vehicle-mounted system is consistent with the first positioning information of the vehicle acquired by the vehicle from the first positioning system, extracting corresponding vehicle identity information as the identity information of the vehicle, namely the vehicle identity information assigned and corresponding by the vehicle-mounted system and the road side system.
The method for processing by the roadside processor to obtain the second positioning information of the vehicle comprises the following steps: when the vehicle information measuring unit is a millimeter wave radar, the roadside processor reads positioning information of a millimeter wave radar installation position preset in the roadside memory, and obtains second positioning information of the vehicle by combining vehicle relative positioning information output by the millimeter wave radar; when the vehicle information measuring unit is a laser radar or a camera, the roadside processor processes point cloud output by the laser radar or image information output by the camera to obtain relative positioning information of the vehicle, and reads positioning information of the installation position of the laser radar or the camera preset in the roadside memory to obtain second positioning information of the vehicle; when the vehicle information measuring unit is a geomagnetic array, the roadside processor judges whether a vehicle passes through according to the received geomagnetic measurement quantity, and reads a geomagnetic sensor number and corresponding longitude and latitude preset in a roadside memory; and the roadside processor confirms the longitude and latitude of the vehicle according to the sensor number, namely determines second positioning information of the vehicle.
In step a2, the clock information is also combined and transmitted.
The second positioning information includes vehicle position information and vehicle speed information.
When the comparison is performed in step a1, the processor of the roadside system compares the second positioning information in the vehicle second positioning information sequence measured by the vehicle information measuring unit of the roadside system with the first positioning information of the vehicle from the roadside wireless communication device, and when the two positioning information are smaller than a certain threshold, the two positioning information can be regarded as the same vehicle.
Further comprising the steps of: a4', broadcasting and sending a relocation request command to request the vehicle-mounted system to send out vehicle identity information and a first locating information sequence of corresponding historical time in an overlapping area; a5', receiving vehicle identity information sent by a vehicle-mounted system and a first positioning information sequence corresponding to historical time; a6', reading the historical second positioning information sequence of the vehicle at the corresponding historical time in the overlapping area stored in the roadside memory, respectively comparing the received historical first positioning information sequence of the vehicle stored in the vehicle-mounted system with the historical second positioning information sequence of different vehicles stored in the roadside system, and judging the same vehicle when the comparison is consistent, thereby realizing the re-matching of the identity information and the positioning information of the vehicle.
Further comprising the steps of: a4' receiving a relocation request command sent by a vehicle-mounted system in a wireless mode; a5', framing and sending the historical second positioning information sequence and the corresponding vehicle identity information sequence of different vehicles in the overlapping area stored in the memory of the road side system; thereby enabling the vehicle-mounted system to realize the following steps: the frame is decoded to obtain an identity information sequence and a corresponding vehicle historical second positioning information sequence; and reading the historical first positioning information sequence of the vehicle in the overlapping area stored in the vehicle-mounted memory, respectively comparing the historical first positioning information sequence with the received historical second positioning information sequences of different vehicles, and judging the vehicle as the own vehicle when finding a consistent person, so that the identification information of the vehicle in the overlapping area of the own vehicle can be determined.
The invention also provides a method for generating and sending the vehicle-road cooperative vehicle positioning signal, which comprises the following steps: a1, in the overlapping area of the action ranges of the first vehicle information measuring unit and the second vehicle information measuring unit, the roadside system processor receives third combined information from the first vehicle information measuring unit, wherein the third combined information comprises a third positioning information sequence and a corresponding vehicle identity information sequence; a2, the roadside system processor respectively compares the third positioning information in the third positioning information sequence with the fourth positioning information in the fourth positioning information sequence of the vehicle measured by the second vehicle information measuring unit, and extracts the vehicle identity information corresponding to the third positioning information as the vehicle identity information of the fourth positioning information which is compared and consistent when the comparison is consistent; a3, continuously measuring by a second vehicle information measuring unit to obtain a fourth positioning information sequence of the vehicle, continuously tracking the vehicle by using the continuity of the motion state of the vehicle in time and space, and matching the identity information of the vehicle with the continuously measured fourth positioning information by a roadside system processor to form a fourth combined information sequence; and A4, sending out the fourth combined information by wireless signal broadcast, so that the roadside system provides the multi-vehicle simultaneous location service for the vehicle-mounted system by using the second vehicle information measuring unit.
In some embodiments, further comprising:
when the vehicle runs out of the overlapping area, the vehicle enters a non-overlapping area in the measuring range of the second vehicle information measuring unit, the second vehicle information measuring unit continuously measures, the roadside system processor combines the vehicle identity information with the corresponding vehicle positioning information, when the vehicle is not less than 2, a vehicle positioning information sequence containing the vehicle identity information is formed, and the vehicle positioning information sequence is sent out in a wireless information mode through the roadside wireless communication device, so that the continuous positioning of multiple vehicles is realized.
And the camera is matched with the image recognition to assist in vehicle identity recognition.
The invention also provides a vehicle-mounted system of the vehicle-road cooperative vehicle positioning system, which comprises a processor, a memory, a satellite navigation receiver and a wireless communication device, wherein the memory stores a computer program, and the computer program can be executed by the processor to realize the method.
The invention also provides a roadside system of the vehicle-road cooperative vehicle positioning system, which comprises a processor, a memory, a vehicle information measuring unit and a wireless communication device, wherein the vehicle information measuring unit and the action range of the satellite positioning signal have an overlapping region; the memory has stored therein a computer program executable by the processor to implement the method described above.
The invention also provides a roadside system of the vehicle-road cooperative vehicle positioning system, which comprises a processor, a memory, two or more vehicle information measuring units and a wireless communication device, and is characterized in that an action range overlapping area is arranged between the adjacent vehicle information measuring units; the memory has stored therein a computer program executable by the processor to implement the method described above.
The invention also provides a vehicle-road cooperative vehicle positioning system which is characterized by comprising the road side system.
Compared with the prior art, the invention has the advantages that: according to the invention, the vehicle identity is obtained by comparing the first positioning information and the second positioning information which are simultaneously obtained in the overlapping area, so that the vehicle identity information is transmitted to the road side system from the vehicle-mounted system, and the road side system can send the vehicle positioning information with the vehicle identity information, therefore, when a plurality of vehicles pass through simultaneously, each vehicle can respectively obtain which positioning information belongs to the vehicle through the matching of the identity information, and thus, the simultaneous positioning of the plurality of vehicles is realized. The roadside system also realizes the long-distance continuous simultaneous positioning of multiple vehicles by utilizing the overlapping area of the roadside information measuring unit.
In some embodiments, the following benefits are also achieved:
when the vehicle identity information is unavailable or mismatched, the road side system also provides positioning information for the vehicle by temporarily endowing the vehicle identity information, so that simultaneous positioning of multiple vehicles is continuously realized.
When the vehicle identity information is unavailable or mismatched, the roadside system can also obtain the identity information of the vehicle through the historical positioning information in the overlapping area in a repositioning request mode, so that the simultaneous positioning of multiple vehicles is continuously realized.
When the vehicle identity information is unavailable or mismatched, the vehicle-mounted system can also obtain the identity information of the vehicle through the historical positioning information in the overlapping area in a repositioning request mode, so that the simultaneous positioning of multiple vehicles is continuously realized.
Further advantageous effects of the invention will be further elucidated in the examples.
Drawings
FIG. 1 is a schematic diagram of a vehicle-road cooperative vehicle positioning system according to an embodiment of the invention.
FIG. 2 is a schematic diagram of an overlap region according to an embodiment of the present invention.
Fig. 3 is a schematic diagram of a positioning scene in a tunnel formed by two vehicle information measurement units according to an embodiment of the present invention.
FIG. 4 is a schematic diagram of determining whether a vehicle is in a detection zone according to an embodiment of the invention.
FIG. 5 is a schematic flow chart of a vehicle-mounted system according to an embodiment of the invention.
FIG. 6 is a schematic view of a multi-vehicle positioning process of the roadside system according to the embodiment of the invention.
FIG. 7 is a schematic diagram of a continuous positioning process of a roadside system according to an embodiment of the invention.
Detailed Description
The invention will be further described with reference to the accompanying drawings and preferred embodiments. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.
It should be noted that the terms of orientation such as left, right, up, down, top and bottom in the present embodiment are only relative concepts to each other or are referred to the normal use state of the product, and should not be considered as limiting.
In view of the above problem that the vehicle-road cooperative vehicle positioning system cannot realize simultaneous positioning of multiple vehicles, the following embodiments of the present patent show a vehicle-road cooperative vehicle positioning system and method for realizing simultaneous positioning of multiple vehicles.
As shown in FIG. 1, the vehicle-road cooperative vehicle positioning system includes a roadside system and an on-board system.
The roadside system includes a vehicle information measurement unit 1 installed at the roadside, a processor 2, and a roadside wireless communication device 3 and a memory (which may be integrated with the processor).
The vehicle information measuring unit may be a sensor such as a radar, a camera, a geomagnetic array, or the like, for measuring vehicle motion information.
Further, the vehicle information measuring unit is a millimeter wave radar, and can simultaneously detect the motion state of the vehicle within a certain distance range, such as the vehicle within a range of 200 meters in 8 lanes, and output the relative position and speed of the vehicle within the region.
Or, the vehicle information measuring unit is a laser radar and can output point clouds within a certain distance range, such as a point cloud map within a range of 200 meters in a 3-lane.
Or the vehicle information measuring unit is a camera and can shoot a video containing vehicle information in a certain area, such as a road video in a range of 4 lanes and 50 meters.
Or the vehicle information measuring unit is a geomagnetic array, one geomagnetic sensor is arranged on the ground at certain intervals to form a geomagnetic sensor array, and the installation position of each geomagnetic sensor is marked; when a vehicle passes by, the corresponding sensor measurement value changes, and the sensor number and the corresponding measurement quantity are output.
The roadside processor can be an ARM processor or a computing unit with computing capability such as an Edge computing unit mec (mobile Edge computing);
the roadside memory is equipment capable of storing data, such as a TF memory card, an EEPROM, a FLASH or a hard disk, and pre-set data are stored in the roadside memory. The roadside memory is connected with the roadside processor.
Further, when the vehicle information measuring unit is a millimeter wave radar, a laser radar and a camera, the preset data in the roadside memory is positioning information of the installation positions of the millimeter wave radar and the laser radar, such as longitude and latitude; when the vehicle information measuring unit is a geomagnetic array, the data preset in the roadside memory are geomagnetic sensor numbers and corresponding longitudes and latitudes.
The roadside wireless communication device may be, but is not limited to, a wireless communication unit of signals such as LTE-V2X or 5G-V2X.
The roadside system may include a roadside clock unit and an onboard clock unit. The road side clock unit is a device capable of providing time information, can be a circuit composed of electronic components such as a GPS satellite navigation receiver device or a crystal oscillator and can provide clock information. The onboard clock unit is connected to an onboard processor.
It is to be emphasized that the processor may be composed of several sub-processors, and the vehicle information measurement unit and/or the roadside wireless communication device may be combined with different sub-processors, respectively. For example, in the existing apparatuses, the roadside wireless communication apparatus is usually integrated with a roadside clock unit, a sub-processor, and a roadside memory into one device, which is called a roadside unit rsu (road Side unit); the vehicle information measurement unit radar is also generally integrated with the sub-processor.
The vehicle-mounted system comprises a satellite navigation receiver, a vehicle-mounted wireless communication device, a vehicle-mounted processor and a vehicle-mounted memory, wherein the satellite navigation receiver, the vehicle-mounted wireless communication device, the vehicle-mounted processor and the vehicle-mounted memory are mounted on a vehicle.
The satellite navigation receiver may output positioning information of the vehicle. The positioning information includes, but is not limited to, the position, speed of the vehicle movement.
The satellite navigation receiver is mounted on the vehicle and connected to the on-board processor.
The satellite navigation receiver can be a GPS receiver, a Beidou receiver, a GPS/Beidou dual-mode receiver or a multi-mode GNSS signal receiver combined with other satellite navigation systems; the receiver comprises an RTK receiver.
Further, the satellite navigation receiver may be used in combination with an IMU inertial measurement unit to improve navigation accuracy. The combined use of the satellite navigation receiver and the IMU inertial measurement unit is a typical usage method in the industry and will not be described herein.
The vehicle-mounted wireless communication device is a communication unit matched with a road side wireless communication device in a road side system and comprises but not limited to signals such as LTE-V2X or 5G-V2X, and the vehicle-mounted wireless communication device and the road side wireless communication device can communicate with each other through wireless signals.
The in-vehicle wireless communication device is connected to an in-vehicle processor.
The onboard processor is a computing unit with computing capabilities, such as an ARM-series processor.
The vehicle-mounted memory is a TF memory card, FLASH or hard disk and other devices capable of storing data. The vehicle identification information is stored in the memory in advance. The vehicle identity information includes, but is not limited to, the license plate number of the vehicle.
The onboard system may include an onboard clock unit. The on-board clock unit is a device capable of providing time information, and may be a circuit composed of electronic components such as the satellite navigation receiver or the crystal oscillator, and may provide clock information. The onboard clock unit is connected to an onboard processor.
In the existing device, the vehicle-mounted wireless communication device, the processor, the vehicle-mounted clock unit and the vehicle-mounted memory are combined together to form a device, which is called an on Board unit (obu).
In the following embodiments of the present application, the roadside system is configured to include an overlap region, namely: the positioning area containing the vehicle identity information and the vehicle positioning information and the positioning area containing no vehicle identity information and only containing the vehicle positioning information have an overlapping area.
The length of the overlapping area is not less than a certain threshold value.
For the GNSS signal and vehicle-road cooperative positioning overlapping area, the value range of the threshold is 5-1000 m, so that the vehicle-mounted system can be ensured to simultaneously obtain enough GNSS positioning information and vehicle-road cooperative positioning information; a preferred value of the threshold is 30 meters.
For the overlapping area of the action range of the vehicle information measuring unit of the vehicle-road cooperative positioning system, the value range of the threshold value is 5-300 meters, so that the roadside system can obtain enough measured values in the overlapping area; a preferred value of the threshold is 10 meters.
And in the overlapping area, the measurement frequency of a vehicle information measurement unit of the road side system is not less than a certain threshold value so as to ensure that the road side system obtains a sufficient number of measurement values in the overlapping area. The value range of the threshold is 1-300 Hz; a preferred value of the threshold is 50 Hz.
If the area is the GNSS signal and the area of overlap of the cooperative localization of the vehicle and the road, the GNSS positioning data received by the satellite navigation receiver in the vehicle-mounted system should meet the following requirements to ensure that the received GNSS can be effectively positioned:
the number of satellites is not less than 4;
furthermore, the intensity factor PDOP of the satellite space geometric distribution is not less than a certain threshold, and the value range of the threshold is 0.01-10; a preferred value of the threshold is 3;
furthermore, the horizontal geometric distribution intensity factor HDOP of the satellite is not less than a certain threshold, and the value range of the threshold is 0.001-2.0; a preferred value of the threshold is 0.5;
furthermore, the plane precision HRMS is not less than a certain threshold, and the value range of the threshold is 0.001-2; a preferred value of the threshold is 0.05.
Example one
In this embodiment, the overlap region is implemented by setting a part of the roadside system in an area covered by GNSS signals, and as shown in fig. 5 and 6, the method for implementing simultaneous positioning of multiple vehicles includes:
and in the area where the roadside system is located, an overlapping area covered by the GNSS signals is formed, and the vehicle-mounted system satellite navigation receiver measures the positioning information of the vehicle in real time and transmits the positioning information to the vehicle-mounted processor.
The vehicle-mounted wireless communication device and the road side wireless communication device in the road side system are communicated with each other through wireless signals.
The vehicle-mounted processor in the vehicle-mounted system frames the vehicle positioning information from the satellite navigation receiver and the vehicle identity information prestored in the vehicle-mounted system according to a certain format, and sends the frame in a wireless signal mode through the vehicle-mounted wireless communication device.
The framing format may be
Figure BDA0003193226630000111
The framing information may include real-time clock information provided by the vehicle-mounted clock unit, and the framing format is as follows. The framing format may be
Figure BDA0003193226630000112
The onboard processor may, in an extensible manner, save the framing information to onboard memory.
And the road side wireless communication device in the road side system receives the wireless signal sent by the vehicle-mounted wireless communication device, converts the wireless signal into an electronic signal and transmits the electronic signal to the processor in the road side system. And a processor in the road side system decodes the frame to obtain the vehicle identity information and the vehicle positioning information.
Meanwhile, a vehicle information measuring unit in the roadside system measures vehicle motion information and then transmits the vehicle motion information to the roadside processor. And the roadside processor processes the vehicle positioning information without the vehicle identity information. And when the number of vehicles in the measuring range is not less than 2, the roadside processor processes the vehicle positioning information sequence which does not contain the vehicle identity information.
The method for obtaining the vehicle positioning information by the roadside processor comprises the following steps:
when the vehicle information measuring unit is a millimeter wave radar, the road side processor reads positioning information of a millimeter wave radar installation position preset in the road side memory, and obtains positioning information (geographical positioning information such as longitude and latitude) of the vehicle by combining vehicle relative positioning information output by the millimeter wave radar.
When the vehicle information measuring unit is a laser radar or a camera, the roadside processor processes point cloud output by the laser radar or image information output by the camera to obtain relative positioning information of the vehicle, reads positioning information of the installation position of the laser radar or the camera preset in the roadside memory, and obtains positioning information (geographical positioning information such as longitude and latitude) of the vehicle.
And when the vehicle information measuring unit is a geomagnetic array, the roadside processor judges whether a vehicle passes through according to the received geomagnetic measurement quantity, and reads the number of the geomagnetic sensor preset in the roadside memory and the corresponding longitude and latitude. And the roadside processor confirms the longitude and latitude of the vehicle according to the sensor number, namely the positioning information of the vehicle is determined.
The roadside processor can store the real-time clock information provided by the roadside clock unit and the vehicle positioning information into the vehicle-mounted memory in an extensible manner.
The vehicle identity information and the positioning information from the roadside wireless communication device, which are obtained by the roadside system processor at a certain moment, are recorded as shown in a table one:
Figure BDA0003193226630000121
note that the vehicle positioning information sequence which is obtained by the roadside system processor at the same time interval and does not contain the vehicle identity information from the vehicle information measurement unit is shown in table two:
Figure BDA0003193226630000122
the processor of the road side system compares the vehicle positioning information from the road side wireless communication device at the same time interval with the vehicle positioning information in the vehicle positioning information sequence from the vehicle information measuring unit of the road side system respectively, and when the vehicle positioning information and the vehicle positioning information are smaller than a certain threshold value, the two vehicles can be considered as the same vehicle, namely the vehicle positioning information from the vehicle information measuring unit obtained by the processor of the road side system is matched with the corresponding vehicle identity information.
When the number of vehicles is not less than 2, the roadside processor receives vehicle positioning information which is sent by each vehicle and contains vehicle identity information, the roadside processor compares the vehicle positioning information of each vehicle with the vehicle positioning information in the vehicle positioning information sequence from the roadside system vehicle information measuring unit respectively, and the vehicle positioning information from the vehicle information measuring unit obtained by the roadside system processor can be matched with the corresponding vehicle identity information.
It is to be noted that, since the information from the roadside wireless communication device and the information from the vehicle information measurement unit may not be in agreement in frequency, the same period of time is a period of time during which both the latest information are received before or after the time.
To determine { pr1,Vr1For example, the vehicle identity information of { p } will ber1,Vr1And { { p { }v1,Vv1},{pv2,Vv2},...,{pvn,VvnAre compared separately, one preferred method is to consider both vehicles the same when they are less than a certain threshold, thus obtaining { p }r1,Vr1The vehicle identity information of.
The comparison method comprises
Figure BDA0003193226630000131
Wherein epsilonpAnd εVIs any value chosen according to the characteristics of the system. And meanwhile, a more accurate comparison result can be obtained by comparing the position information with the speed information.
Notably, p isrThe position of the representation is generally expressed as a position p in 3 directions in space in practical applicationrx,pry,przSame principle, VrAlso denoted as { Vrx,Vry,VrzIs then the above formula can be further expressed as
Figure BDA0003193226630000132
Wherein epsilonpx,εpy,εpzAnd εVx,εVy,εVzIs a value selected according to the characteristics of the system.
A selection method is that according to positioning errors of a satellite navigation receiver provided by a product manual of the satellite navigation receiver and positioning errors of a vehicle information measuring unit of a road side system provided by a vehicle information measuring unit manual of the road side system, the sum of the positioning errors is 1.5 times. For example, if the position error and the speed error of the satellite navigation receiver are 0.3m and 0.1m/s, and the position accuracy and the speed error of the road side system vehicle information measuring unit are 0.5m and 0.2m/s, then epsilon is takenpx、εpyAnd εpz1.5 (0.3+0.5) ═ 1.2, let ε be takenVx、εVyAnd εVzIs 1.5 × (0.1+0.2) ═ 0.45)
Further, may be for { εpx,εpy,εpzAnd eVx,εVy,εVzComparing any norm of e.g.
Figure BDA0003193226630000133
Wherein epsilonpAnd εVIs a value selected according to the characteristics of the system.
A selection method is that according to positioning errors of a satellite navigation receiver provided by a product manual of the satellite navigation receiver and positioning errors of a vehicle information measuring unit of a road side system provided by a vehicle information measuring unit manual of the road side system, the sum of the positioning errors is 1.5 times. For example, if the position error and the speed error of the satellite navigation receiver are 0.3m and 0.1m/s, and the position accuracy and the speed error of the road side system vehicle information measuring unit are 0.5m and 0.2m/s, then epsilon is takenp1.5 (0.3+0.5) ═ 1.2, let ε be takenVThe ratio was 1.5 × (0.1+0.2) ═ 0.45.
It is also possible to compare only the location information in the xy-direction, i.e. to compare
Figure BDA0003193226630000141
Further, in order to improve the accuracy of matching, the comparison may be performed continuously for a certain time or for a certain number of times. When the condition is met for a continuous time or a certain number of times, the vehicle can be confirmed to be the same vehicle, and matching of the vehicle identity information and the vehicle positioning information of the road side system is achieved. At this time, the roadside system processor obtains a vehicle positioning information sequence including vehicle identification information.
Then, the roadside system processor can frame the vehicle identity information and the positioning information sequence according to a certain format and broadcast and send the vehicle identity information and the positioning information sequence in a wireless information mode through the roadside wireless communication device. The framing format may be
Figure BDA0003193226630000142
The vehicle-mounted wireless communication device receives the wireless information, converts the wireless information into electronic information and transmits the electronic information to the vehicle-mounted processor, and the vehicle-mounted processor obtains a vehicle positioning information sequence containing vehicle identity information after analysis.
The vehicle-mounted processor reads the vehicle identity information prestored in the vehicle-mounted system memory, compares the vehicle identity information with the vehicle identity information in the received vehicle positioning information sequence, and if the vehicle identity information is the same as the own vehicle identity, the corresponding positioning information is the own positioning information. For example, the vehicle identity information 2 in the vehicle positioning information sequence is the same as the vehicle identity information pre-stored in the memory, and then the positioning information of the current vehicle is the vehicle positioning information 2.
In this way, the positioning of the vehicle is achieved. Once the matching of the vehicle identity information and the vehicle positioning information is completed, the matching of the vehicle identity information and the vehicle positioning information can be realized by utilizing the continuity of the vehicle motion state in time and space. The road side system processor frames the vehicle identity information and corresponding vehicle positioning information obtained by processing the vehicle motion information measured by the road side system vehicle information measuring unit, and sends the frame in a wireless information mode through the road side wireless communication device. The vehicle-mounted wireless communication device and the vehicle-mounted processor repeat the above steps, and the vehicle can obtain the vehicle self-positioning information from the road side system.
The continuity of the motion state of the vehicle in time and space means that the difference between the adjacent two times of the vehicle positioning information (such as the position) is not large because the time interval between the two adjacent times of the processor is short. If the difference is less than a selected value, it is considered the position of the same vehicle at two adjacent times.
Further, the roadside system comprises a roadside clock unit, and the on-board system comprises an on-board clock unit.
The road side clock unit and the vehicle-mounted clock unit are devices capable of providing time information, and can be circuits formed by electronic components such as the satellite navigation receiver device or a crystal oscillator and the like, and can provide real-time clock information. The road side clock unit is connected to the road side processor, and the vehicle-mounted clock unit is connected to the vehicle-mounted processor.
The vehicle-mounted processor in the vehicle-mounted system reads real-time clock information provided by the vehicle-mounted clock unit, frames the real-time clock information together with vehicle positioning information of the self-satellite navigation receiver and vehicle identity information prestored in the vehicle-mounted system according to a certain format, and sends the frame in a wireless signal mode through the vehicle-mounted wireless communication device. And simultaneously, the vehicle-mounted processor stores the framing information into a vehicle-mounted memory.
The framing format may be
Figure BDA0003193226630000151
And the road side wireless communication device in the road side system receives the wireless signal sent by the vehicle-mounted wireless communication device, converts the wireless signal into an electronic signal and transmits the electronic signal to the processor in the road side system. And a processor in the road side system decodes the frame to obtain the vehicle identity information and the vehicle positioning information. When the number of the vehicles is not less than 2, a processor in the road side system obtains a vehicle identity information sequence and a corresponding vehicle positioning information sequence.
Meanwhile, a vehicle information measuring unit in the roadside system measures vehicle motion information and then transmits the vehicle motion information to the roadside processor. And the roadside processor processes the vehicle positioning information without the vehicle identity information. When the number of vehicles is not less than 2, the roadside processor obtains a vehicle positioning information sequence which does not contain vehicle identity information.
And the roadside processor reads the real-time clock information provided by the roadside clock unit and stores the real-time clock information and the vehicle positioning information sequence which does not contain the vehicle identity information into the roadside memory.
Further, when the roadside system does not receive the vehicle positioning information containing the vehicle identity information sent by the vehicle-mounted system due to some abnormal reasons (such as unexpected situations like wireless communication packet loss) and the matching of the vehicle identity information and the vehicle position information by the roadside system in the overlapping area fails, the roadside system broadcasts and sends a relocation request command. The relocation request command may be predefined specific information, such as a "request location" character.
After the vehicle-mounted system receives the repositioning request information, the vehicle-mounted processor reads the vehicle historical positioning information sequence in the overlapping area stored in the vehicle-mounted memory, and frames the vehicle historical positioning information sequence together with the vehicle identity information and sends the vehicle historical positioning information sequence to the roadside system. The framing format may be
Figure BDA0003193226630000161
And after receiving the information, the road side system obtains the historical positioning information sequence of the vehicle in the overlapping area, which is stored by the vehicle-mounted system, the road side system processor reads the historical positioning information sequence of different vehicles from the road side system in the overlapping area, which is stored by the road side memory, compares the historical positioning information sequence with the historical positioning information of the vehicle, which is stored by the vehicle-mounted system, and judges the vehicle as the same vehicle when the historical positioning information sequence and the historical positioning information of the vehicle are consistent, so that the matching of the vehicle identity information and the vehicle positioning information of the road side system in the overlapping area can be realized. And the identity matching of the current vehicle can be completed according to the continuity of the motion state of the vehicle in time and space in later time.
A preferred comparison method is that a certain number of time points are randomly selected in a historical time period corresponding to the overlap region, difference values between the historical positioning information of the same vehicle stored by the road side system and the historical positioning information of the vehicle from the vehicle-mounted system at different time points are respectively calculated, if the difference values of the two at all the time points are smaller than a certain threshold value, the two are considered to be consistent, that is, the same vehicle is judged, that is, the vehicle is re-matched with the corresponding vehicle identity by the road side system. The historical positioning information of different vehicles stored in the road side system is processed in sequence, so that the identity information and the positioning information of all vehicles can be re-matched. The positioning information may be a vehicle position.
Further, since the operating frequencies of the on-board system and the roadside system may not be completely the same, so that the timestamp of the vehicle historical positioning information stored by the on-board system and the timestamp of the vehicle historical positioning information stored by the roadside system may not be completely consistent, the time point may be a time period before the time point and including the on-board system and the roadside system recording the latest data or a time period before and after the time point and including the on-board system and the roadside system recording the latest data.
Example two
The embodiment provides another method for completing vehicle identity matching, which specifically comprises the following steps:
a roadside processor of the roadside system assigns a temporary identity to the vehicle location information, the temporary identity being valid at a later time.
One preferable method for giving temporary identity is that the position of the vehicle positioning information is numbered from small to large according to the x-axis value, and the number is 001, 002 … …
And the roadside processor frames the temporary identity and vehicle positioning information obtained by processing the vehicle motion information measured by the roadside system vehicle information measuring unit according to a certain format, and transmits the framed vehicle positioning information to the roadside wireless communication device to be sent out in a wireless signal mode. When the number of the vehicles is not less than 2, the temporary identity is a temporary identity sequence, and the vehicle positioning information is a vehicle positioning information sequence.
The framing format may be such that,
Figure BDA0003193226630000171
and in an expandable way, the roadside processor reads the real-time information provided by the roadside clock unit and stores the real-time information, the temporary identity sequence and the vehicle positioning information sequence into the roadside memory according to a certain format. The format may be
Figure BDA0003193226630000172
And the vehicle-mounted wireless communication device in the vehicle-mounted system receives the wireless signal sent by the road-side wireless communication device and transmits the wireless signal to the vehicle-mounted processor. And the vehicle-mounted processor decodes the frame to obtain a temporary identity sequence and a corresponding vehicle positioning information sequence.
The vehicle-mounted processor reads the positioning information of the vehicle measured by the satellite navigation receiver in real time, compares the positioning information with the vehicle positioning information in the vehicle positioning information sequence respectively, and when the difference value of the two is smaller than a certain threshold value, the two are considered as the positioning data of the same vehicle, namely the vehicle determines the temporary identity of the vehicle.
In an extensible way, the vehicle-mounted processor reads the real-time information provided by the vehicle-mounted clock unit and stores the real-time information and the vehicle positioning information measured by the satellite navigation receiver in a certain format into the vehicle-mounted memory. The format may be
Time information Vehicle positioning information
And then, the vehicle-mounted wireless communication device in the vehicle-mounted system receives the wireless signal sent by the road-side wireless communication device and transmits the wireless signal to the vehicle-mounted processor. And the vehicle-mounted processor decodes the frame to obtain a temporary identity sequence and a corresponding vehicle positioning information sequence.
And comparing the temporary identity obtained for the first time with the elements in the temporary identity sequence by the vehicle-mounted processor, wherein when the two temporary identities are the same, the corresponding vehicle positioning information is the current positioning information of the vehicle.
The above process is repeated later.
Therefore, the vehicle-road cooperative vehicle positioning system realizes the simultaneous positioning of a plurality of vehicles, and can provide simultaneous positioning service for the plurality of vehicles even under the condition that a road side system cannot receive vehicle positioning information which is sent by a vehicle-mounted system and measured by a satellite navigation receiver in real time.
Further, when the vehicle-mounted system does not complete the matching with the vehicle temporary identity information in the overlapping area due to some abnormal reasons (such as unexpected situations like wireless communication packet loss) that the vehicle-mounted system does not receive the vehicle positioning information containing the vehicle temporary identity information sent by the roadside system), and the vehicle-mounted system needs to be re-matched, the vehicle-mounted system sends the relocation request command in a wireless mode. The relocation request command may be predefined specific information, such as a "request location" character.
After the roadside system receives the relocation request information, the roadside processor reads different vehicle historical positioning information sequences in the overlapping area stored in the vehicle-mounted memory, and frames the different vehicle historical positioning information sequences with the corresponding vehicle temporary identity sequences together to send the vehicle historical positioning information sequences to the roadside system. The framing format may be, for example, in the form of:
Figure BDA0003193226630000181
and the vehicle-mounted wireless communication device in the vehicle-mounted system receives the wireless signal sent by the road-side wireless communication device and transmits the wireless signal to the vehicle-mounted processor. And the vehicle-mounted processor decodes the frame to obtain a temporary identity sequence and a corresponding vehicle historical positioning information sequence.
The vehicle-mounted processor reads the vehicle historical positioning information sequence in the overlapping area stored in the vehicle-mounted memory, compares the vehicle historical positioning information sequence with the received historical positioning information sequences of different vehicles respectively, and judges the same vehicle when the vehicle historical positioning information sequences are consistent with the received historical positioning information sequences of different vehicles, so that the temporary identity information of the vehicle in the overlapping area of the vehicle can be determined. And then extracting the positioning information corresponding to the temporary identity from the information sent by the road side system, thereby realizing subsequent positioning.
A preferred comparison method is that a certain number of time points are randomly selected in a historical time period corresponding to the overlap region, a difference between the historical positioning information of the vehicle stored in the vehicle-mounted system at each time point and the historical positioning information of the same vehicle from the roadside system is respectively calculated, if the difference between the two time points is smaller than a certain threshold value, the two time points are considered to be consistent, that is, the vehicle is judged to be the same vehicle, and the temporary identity information corresponding to the roadside system is the temporary identity information of the vehicle matched by the vehicle-mounted system to the roadside system.
Further, since the operating frequencies of the on-board system and the roadside system may not be completely the same, so that the timestamp of the vehicle historical positioning information stored by the on-board system and the timestamp of the vehicle historical positioning information stored by the roadside system may not be completely consistent, the time point may be a time period before the time point and including the on-board system and the roadside system recording the latest data or a time period before and after the time point and including the on-board system and the roadside system recording the latest data.
When the GNSS signal of the area where the roadside system is located disappears, although the satellite navigation receiver of the vehicle-mounted positioning system cannot receive the effective GNSS signal and cannot work normally, the vehicle-mounted processor cannot obtain the positioning information from the satellite navigation receiver; but the vehicle-road cooperative vehicle positioning system still works normally, and the vehicle-mounted processor can still obtain the vehicle positioning information from the roadside system.
EXAMPLE III
The embodiment is to realize continuous positioning of multiple vehicles in a large-area long-distance range on the premise that the embodiment realizes matching of vehicle positioning information and vehicle identity information. An overlap region is also used in this example: the vehicle information measuring units of the road side system are sequentially arranged on the road side, so that the action range is ensured to have an appropriate range overlapping area and to be mutually connected in a seamless manner, and the whole action range can fully cover the specified road section.
The following description will take an example in which the vehicle information measurement unit group is two vehicle information measurement units, as shown in fig. 2.
A. B is the action range of the two vehicle information measuring units respectively, and C is the overlapping area of the two action ranges.
As shown in fig. 7, the method is described as follows:
when the vehicle passes through the overlapping area of the action ranges of the vehicle information measuring units, a road side processor in the road side system simultaneously receives the vehicle motion information measured by the first vehicle information measuring unit and the vehicle motion information measured by the second vehicle information measuring unit in the road side system, and a third vehicle positioning information sequence and a fourth vehicle positioning information sequence are obtained after processing.
And the roadside system processor respectively compares the vehicle positioning information in the fourth vehicle positioning information sequence with the vehicle positioning information in the third vehicle positioning information sequence, and if the difference value between the vehicle positioning information in the fourth vehicle positioning information sequence and the vehicle positioning information in the third vehicle positioning information sequence is less than a certain threshold value, the vehicles are considered to be the same vehicle, so that the identity matching of the vehicle positioning information measured by the second vehicle information measuring unit is completed.
Then, if the vehicle is still in the overlapping area of the action range of the vehicle information measuring unit, for the second vehicle information measuring unit, there are two methods to identify the vehicle identity information:
one is to identify the vehicle identity by using the temporal and spatial continuity of the vehicle motion state. The identification method is to compare the current vehicle positioning information with the last vehicle positioning information of the second vehicle information measuring unit, and if the position difference between the current vehicle positioning information and the last vehicle positioning information is smaller than a certain threshold value, the vehicles are considered to be the same vehicle, and the vehicle identity identification is completed.
And if the difference value between the vehicle positioning information in the fourth vehicle positioning information sequence and the vehicle positioning information in the third vehicle positioning information sequence is smaller than a certain threshold value, the vehicle positioning information is regarded as the same vehicle, and therefore the identity matching of the vehicle positioning information measured by the second vehicle information measuring unit is completed.
The roadside processor combines the vehicle identity information and the corresponding vehicle positioning information respectively to form a vehicle positioning information combination sequence containing the vehicle identity information, and sends the vehicle positioning information combination sequence in a wireless information mode through the roadside wireless communication device.
The above process is repeated later.
When the vehicle moves out of the overlapping area, the vehicle enters a non-overlapping area in the measuring range of the second vehicle information measuring unit, the vehicle information measuring unit in the road side system measures, and the road side processor in the road side system receives the vehicle motion information measured by the vehicle information measuring unit in the road side system and obtains vehicle positioning information after processing.
And the vehicle identity is identified by utilizing the continuity of the motion state of the vehicle in time and space. The roadside processor frames the vehicle identity information and the vehicle positioning information and sends the information in a wireless information mode through the roadside wireless communication device.
In this way, a continuous positioning of the vehicles is achieved.
Examples are:
for the positioning scene in the tunnel formed by two vehicle information measuring units, as shown in FIG. 3
The vehicle runs from left to right, A, B is the action range of the first and second vehicle information measuring units respectively, C is the overlapping area of the action ranges of the first and second vehicle information measuring units, D is a section of road outside the tunnel in the tunnel direction, and is the overlapping area of the first vehicle information measuring unit and the GNSS signal.
Matching and simultaneous positioning of the identity and vehicle positioning information of the multiple vehicles are completed in the area D by the method in the embodiment 1.
And in the area A in the tunnel, matching and simultaneous positioning of the identity and the vehicle positioning information of the vehicles of the multiple vehicles are completed through the continuity of the motion state of the vehicles in time and space.
And in the overlapping area C of the action ranges of the first vehicle information measuring unit and the second vehicle information measuring unit, matching and simultaneous positioning of the identity and the vehicle positioning information of multiple vehicles are completed according to the continuity of the motion state of the vehicles in time and space or by comparing the vehicle positioning information from the first vehicle information measuring unit and the second vehicle information measuring unit in the road side system.
And the area B in the tunnel and the area A in the tunnel complete the matching and simultaneous positioning of the identity of the multiple vehicles and the positioning information of the vehicles through the continuity of the motion state of the vehicles in time and space.
Therefore, continuous positioning of multiple vehicles in the tunnel environment is achieved.
Example four
The embodiment shows another vehicle-road cooperative vehicle positioning system and method for realizing simultaneous positioning of multiple vehicles, which can be used for the assistance of the method in the above embodiment.
In this embodiment, the roadside system includes a vehicle information measurement unit installed at the roadside, a roadside camera, a roadside processor, a roadside memory, and a roadside wireless communication device.
The vehicle information measuring unit may be a sensor such as a radar, a camera, a geomagnetic array, or the like, for measuring vehicle motion information.
The method for realizing the simultaneous positioning of the multiple vehicles comprises the following steps:
and a vehicle information measuring unit in the road side system transmits the measured vehicle motion information to a road side processor, and the road side processor processes the vehicle motion information to obtain a vehicle positioning information sequence. And meanwhile, the identity information of the vehicle is identified.
One preferable vehicle identification information recognition method is as follows:
and the road side processor reads the preset detection area positioning information in the road side memory and judges whether the vehicle is in the detection area or not according to the vehicle positioning information of the road side processor.
For example, as shown in fig. 4, the vehicle position of the vehicle positioning information is { p }x,pyThe position of the positioning information of the detection area is that four angular points are ({ p) in sequence1x,p1y},{p2x,p2y},{p3x,p3y},{p4x,p4y}) of the rectangular shape, judges { px,pyWhether it is inside the rectangle.
The judging method can be
Figure BDA0003193226630000221
εxAnd εyAny number not less than 0 selected according to the motion characteristics of the vehicle, such as
εx＝n·Vx·Δt
εy＝n·Vy·Δt
Wherein, VxAnd VySpeed of the vehicle in x and y directions, respectively, Δ t is a measurement time interval of the vehicle information measuring unit, and n is an arbitrary number from 0 to 3.
When the above formula is established, the vehicle enters the detection area; otherwise the vehicle does not enter the detection zone.
When the vehicle is judged to enter the detection area, the roadside processor controls the roadside camera to take a picture. The road side camera transmits the shot picture to the road side processor, and the road side processor performs license plate recognition on the picture to obtain a vehicle identity information sequence.
Another preferable method of recognizing the vehicle identification information is,
the roadside processor reads a detection area image preset in the roadside memory and sends the detection area image to a sub-processor (integrated with the roadside camera) of the roadside processor, and the sub-processor of the roadside processor detects whether the vehicle is in the detection area or not according to the detection area image.
The roadside camera uninterruptedly shoots images in the detection area and transmits the images to the subprocessor of the roadside processor, and the subprocessor performs target detection locally and detects whether vehicles enter the detection area. When the fact that the vehicle enters the detection area is detected, the sub-processor conducts license plate recognition on the current shot image and sends a detection result and a license plate number information sequence to the road side processor. The method is already well applied to video vehicle detectors (for example, the document: design and development of video vehicle detector products of Zhumin, Zhejiang university of industry, and for example, a webpage: http:// www.ia.cas.cn/kygz/cgzh/201210/t20121031_3674522.html), and details are not repeated herein. When it is not detected that the vehicle enters the detection area, no processing is performed.
The roadside processor takes the license plate number information sequence as a vehicle identity information sequence, frames the vehicle identity information sequence and a corresponding vehicle positioning information sequence according to a certain format, and sends the vehicle identity information sequence and the corresponding vehicle positioning information sequence in a wireless information mode through the roadside wireless communication device. The framing format may be
Figure BDA0003193226630000222
The vehicle-mounted wireless communication device receives the wireless information, converts the wireless information into electronic information and transmits the electronic information to the vehicle-mounted processor, and the vehicle-mounted processor obtains a vehicle positioning information sequence containing vehicle identity information after analysis.
And comparing the vehicle identity information in the vehicle positioning information sequence with the vehicle identity information prestored in the memory by the vehicle-mounted processor, and when the vehicle identity information and the vehicle identity information are the same, determining the vehicle positioning information corresponding to the vehicle identity information as the positioning information of the vehicle.
And then, a vehicle information measuring unit in the road side system measures, and a road side processor in the road side system receives the vehicle motion information measured by the vehicle information measuring unit in the road side system and obtains a vehicle positioning information sequence after processing.
And matching the vehicle identity and the vehicle positioning information by utilizing the continuity of the vehicle motion state in time and space. The identification method comprises the steps of comparing the current vehicle positioning information with the last vehicle positioning information, and if the position difference between the current vehicle positioning information and the last vehicle positioning information is smaller than a certain threshold value, the same vehicle is considered, and the matching of the vehicle identity and the vehicle positioning information is completed.
The roadside processor frames the vehicle identity information and the vehicle positioning information and sends the information in a wireless information mode through the roadside wireless communication device.
The vehicle-mounted wireless communication device receives the wireless information, converts the wireless information into electronic information and transmits the electronic information to the vehicle-mounted processor, and the vehicle-mounted processor obtains a vehicle positioning information sequence containing vehicle identity information after analysis.
And comparing the vehicle identity information in the vehicle positioning information sequence with the vehicle identity information prestored in the vehicle-mounted memory by the vehicle-mounted processor, and when the vehicle identity information and the vehicle identity information are the same, determining the vehicle positioning information corresponding to the vehicle identity information as the positioning information of the vehicle.
And measuring for the third time, and repeating the process for the second time.
Thus, the vehicle-road cooperative vehicle positioning system realizes the simultaneous positioning of multiple vehicles.
The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several equivalent substitutions or obvious modifications can be made without departing from the spirit of the invention, and all the properties or uses are considered to be within the scope of the invention.

Claims (22)

1. A vehicle-road cooperative vehicle positioning method is characterized by comprising the following steps:
s1, obtaining first positioning information of the vehicle, which is measured in an overlapping area of a first positioning system and a second positioning system, wherein the first positioning information of the vehicle is measured by a first positioning system on a vehicle-mounted system; the system is communicated with a road side system to realize assignment and correspondence of vehicle identity information of the same vehicle with the road side system, so that second combined information sent by a subsequent road side system in a broadcasting mode can contain the vehicle identity information subjected to assignment and correspondence and second positioning information corresponding to the vehicle; when the number of vehicles is not less than 2, the plurality of second combined information form a second combined information sequence; the second positioning information of the vehicle is measured by a second positioning system on the road side system;
and S2, when the positioning is required to be carried out through the second positioning system, repeatedly receiving a second combined information sequence sent by the road side system through a broadcasting mode, extracting the vehicle identity information in the second combined information sequence, and when the extracted identity information is consistent with the identity information of the vehicle, determining that the second positioning information corresponding to the identity information contained in the second combined information is the second positioning information of the vehicle measured by the road side system.
2. The vehicle-road cooperative vehicle positioning method according to claim 1, wherein in step S1, the vehicle identification information is identification information inherent to the vehicle or vehicle identification information temporarily distributed by a roadside system; the method for realizing the assignment and correspondence of the vehicle identity information by the vehicle-mounted system and the road side system through the communication with the road side system comprises at least one of the following steps:
the method comprises the following steps: combining the first positioning information and the vehicle identity information to form first combined information which is sent out by a wireless signal, so that a road side system can execute the following steps: respectively comparing the first positioning information in the first combined information with second positioning information in a second positioning information sequence of the vehicle at the same time period, which is measured by a road side system, and extracting vehicle identity information in the first combined information when the comparison is successful, wherein the vehicle identity information is the vehicle identity information for realizing assignment correspondence of the vehicle-mounted system and the road side system;
the second method comprises the following steps: and receiving a second combined information sequence sent by the road side system in a broadcasting mode, extracting second positioning information of the vehicle measured by the road side system contained in the second combined information and vehicle identity information temporarily distributed to the vehicle by the road side system corresponding to the second positioning information, and when the extracted second positioning information is consistent with the first positioning information of the vehicle obtained from the first positioning system by the vehicle, extracting corresponding identity information as the identity information of the vehicle, namely the vehicle identity information assigned and corresponding by the vehicle-mounted system and the road side system.
3. The method for vehicle-road cooperative vehicle localization according to claim 1, further comprising the steps of:
and S3, at least when the first positioning information is not available subsequently, the second positioning information is used as the self positioning information of the vehicle to realize continuous navigation or automatic driving.
4. The method according to claim 1, wherein the first combination information further comprises real-time clock information.
5. The vehicle-road cooperative vehicle positioning method according to claim 1, wherein the first positioning information includes vehicle position information and vehicle speed information.
6. The vehicle-road cooperative vehicle positioning method according to claim 1, characterized by further comprising the steps of:
s4, receiving relocation request information from a road side system;
s5, reading a vehicle historical first positioning information sequence in an overlapping area stored in a vehicle-mounted memory, framing the first positioning information sequence and vehicle identity information, and sending the first positioning information sequence and the vehicle identity information to a roadside system; the framing comprises historical time information, vehicle positioning information corresponding to the historical time and self vehicle identity information; so that the road side can realize the re-matching of the vehicle identity information and the vehicle positioning information.
7. The vehicle-road cooperative vehicle positioning method according to claim 1, characterized by further comprising the steps of:
s5', sending a relocation request command in a wireless mode;
s6', receiving historical second positioning information sequences and corresponding vehicle identity information sequences of different vehicles in the overlapping region stored in a road side memory which is sent by framing of a road side system;
s7', decoding the frame to obtain an identity information sequence and a corresponding vehicle history second positioning information sequence;
s8', reading the vehicle history first positioning information sequence in the overlapping area stored in the vehicle-mounted memory, comparing with the received vehicle history second positioning information sequence of different vehicles, judging as the vehicle when finding the consistent person, and determining the vehicle identity information in the overlapping area of the vehicle.
8. A method for generating and sending a vehicle-road cooperative vehicle positioning signal is characterized by comprising the following steps:
a1, obtaining second positioning information of the vehicle measured in an overlapping area of the first positioning system and the second positioning system, wherein the second positioning information of the vehicle is measured by a second positioning system on the road side; the system is communicated with a vehicle-mounted system to realize the assignment and the correspondence of the vehicle identity information of the same vehicle with the vehicle-mounted system;
a2, sending second combined information in a broadcast mode, wherein the second combined information comprises vehicle identity information corresponding to the assignment and second positioning information corresponding to the vehicle; when the vehicle is not less than 2, the plurality of second combined information forms a second combined information sequence.
9. The method for generating and transmitting a vehicle-road cooperative vehicle locating signal according to claim 8,
the vehicle identity information is inherent identity information of a vehicle or temporarily distributed by a road side system;
the step a1 is performed with a vehicle-mounted system, and the method for implementing assignment and correspondence of vehicle identity information by the vehicle-mounted system and the road side system includes at least one of the following steps:
the method comprises the following steps: receiving first combined information sent by a vehicle-mounted system through a wireless signal, wherein the first combined information comprises first positioning information and vehicle identity information, respectively comparing the first positioning information in the first combined information with second positioning information in a vehicle second positioning information sequence of the same time period measured by a road side system, and extracting the vehicle identity information in the first combined information when the comparison is successful, namely the vehicle identity information for realizing assignment correspondence of the vehicle-mounted system and the road side system; the first positioning information of the vehicle is measured by a first positioning system on the vehicle-mounted system;
the second method comprises the following steps: sending a second combined information sequence in a broadcasting mode, wherein the second combined information comprises second positioning information of the vehicle measured by the road side system and vehicle identity information temporarily distributed to the vehicle by the road side system corresponding to the second positioning information; and when the second positioning information extracted by the vehicle-mounted system is consistent with the first positioning information of the vehicle acquired by the vehicle from the first positioning system, extracting corresponding vehicle identity information as the identity information of the vehicle, namely the vehicle identity information assigned and corresponding by the vehicle-mounted system and the road side system.
10. The method for generating and transmitting the vehicle-road cooperative vehicle positioning signal according to claim 8, wherein the method for the roadside processor to process and obtain the second positioning information of the vehicle comprises:
when the vehicle information measuring unit is a millimeter wave radar, the roadside processor reads positioning information of a millimeter wave radar installation position preset in the roadside memory, and obtains second positioning information of the vehicle by combining vehicle relative positioning information output by the millimeter wave radar;
when the vehicle information measuring unit is a laser radar or a camera, the roadside processor processes point cloud output by the laser radar or image information output by the camera to obtain relative positioning information of the vehicle, and reads positioning information of the installation position of the laser radar or the camera preset in the roadside memory to obtain second positioning information of the vehicle;
when the vehicle information measuring unit is a geomagnetic array, the roadside processor judges whether a vehicle passes through according to the received geomagnetic measurement quantity, and reads a geomagnetic sensor number and corresponding longitude and latitude preset in a roadside memory; and the roadside processor confirms the longitude and latitude of the vehicle according to the sensor number, namely determines second positioning information of the vehicle.
11. The method for generating and transmitting a vehicle-road cooperative vehicle-positioning signal according to claim 8, wherein in step a2, the clock information is also transmitted in combination.
12. The method for generating and transmitting a vehicle-road cooperative vehicle locating signal according to claim 8, wherein the second locating information includes vehicle position information and vehicle speed information.
13. The method for generating and transmitting the vehicle-road cooperative vehicle positioning signal according to claim 9, wherein when the comparing in step a1, the processor of the roadside system compares the second positioning information in the second positioning information sequence of the vehicle measured by the vehicle information measuring unit of the roadside system with the first positioning information of the vehicle from the roadside wireless communication device, and when the two positioning information are smaller than a certain threshold, the two positioning information are considered as the same vehicle.
14. The method for generating and transmitting the vehicle-road cooperative vehicle positioning signal according to claim 8, further comprising the steps of:
a4', broadcasting and sending a relocation request command to request the vehicle-mounted system to send out vehicle identity information and a first locating information sequence of corresponding historical time in an overlapping area;
a5', receiving vehicle identity information sent by a vehicle-mounted system and a first positioning information sequence corresponding to historical time;
a6', reading the historical second positioning information sequence of the vehicle at the corresponding historical time in the overlapping area stored in the roadside memory, respectively comparing the received historical first positioning information sequence of the vehicle stored in the vehicle-mounted system with the historical second positioning information sequence of different vehicles stored in the roadside system, and judging the same vehicle when the comparison is consistent, thereby realizing the re-matching of the identity information and the positioning information of the vehicle.
15. The method for generating and transmitting the vehicle-road cooperative vehicle positioning signal according to claim 8, further comprising the steps of:
a4' receiving a relocation request command sent by a vehicle-mounted system in a wireless mode;
a5', framing and sending the historical second positioning information sequence and the corresponding vehicle identity information sequence of different vehicles in the overlapping area stored in the memory of the road side system; thereby enabling the vehicle-mounted system to realize the following steps: the frame is decoded to obtain an identity information sequence and a corresponding vehicle historical second positioning information sequence; and reading the historical first positioning information sequence of the vehicle in the overlapping area stored in the vehicle-mounted memory, respectively comparing the historical first positioning information sequence with the received historical second positioning information sequences of different vehicles, and judging the vehicle as the own vehicle when finding a consistent person, so that the identification information of the vehicle in the overlapping area of the own vehicle can be determined.
16. A method for generating and sending a vehicle-road cooperative vehicle positioning signal is characterized by comprising the following steps:
a1, in the overlapping area of the action ranges of the first vehicle information measuring unit and the second vehicle information measuring unit, the roadside system processor receives third combined information from the first vehicle information measuring unit, wherein the third combined information comprises a third positioning information sequence and a corresponding vehicle identity information sequence;
a2, the roadside system processor respectively compares the third positioning information in the third positioning information sequence with the fourth positioning information in the fourth positioning information sequence of the vehicle measured by the second vehicle information measuring unit, and extracts the vehicle identity information corresponding to the third positioning information as the vehicle identity information of the fourth positioning information which is compared and consistent when the comparison is consistent;
a3, continuously measuring by a second vehicle information measuring unit to obtain a fourth positioning information sequence of the vehicle, continuously tracking the vehicle by using the continuity of the motion state of the vehicle in time and space, and matching the identity information of the vehicle with the continuously measured fourth positioning information by a roadside system processor to form a fourth combined information sequence;
and A4, sending out the fourth combined information by wireless signal broadcast, so that the roadside system provides the multi-vehicle simultaneous location service for the vehicle-mounted system by using the second vehicle information measuring unit.
17. The method according to claim 16, wherein when the vehicle exits the overlapping area and enters a non-overlapping area within a measurement range of the second vehicle information measurement unit, the second vehicle information measurement unit continuously performs measurement, the roadside system processor combines the vehicle identification information with the corresponding vehicle positioning information, and when the number of vehicles is not less than 2, a vehicle positioning information sequence containing the vehicle identification information is formed and sent out in a wireless information manner through the roadside wireless communication device, thereby realizing continuous positioning of multiple vehicles.
18. The method for generating and transmitting the vehicle-road cooperative vehicle positioning signal according to any one of claims 16 to 17, wherein a camera is used in cooperation with image recognition assistance for vehicle identification.
19. A vehicle-mounted system for a vehicle-road cooperative vehicle positioning system, comprising a processor, a memory, a satellite navigation receiver, and a wireless communication device, the memory having stored therein a computer program executable by the processor to perform the method of any one of claims 1-7.
20. A road side system of a vehicle-road cooperative vehicle positioning system comprises a processor, a memory, a vehicle information measuring unit and a wireless communication device, and is characterized in that the action ranges of the vehicle information measuring unit and a satellite positioning signal have an overlapping region; the memory has stored therein a computer program executable by a processor to implement the method of any one of claims 8-15.
21. A road side system of a vehicle-road cooperative vehicle positioning system comprises a processor, a memory, two or more vehicle information measuring units and a wireless communication device, and is characterized in that an action range overlapping area is arranged between the adjacent vehicle information measuring units; the memory has stored therein a computer program executable by a processor to implement the method of any one of claims 16-18.
22. A vehicle-road cooperative vehicle positioning system characterized by comprising an on-board system as claimed in claim 19 and a roadside system as claimed in claim 20 or 21.
CN202110883855.3A 2021-06-01 2021-08-03 Vehicle-road cooperative vehicle positioning system and method for realizing simultaneous positioning of multiple vehicles Pending CN113781819A (en)

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