Traffic incident detection method based on intelligent spikes

Abstract

The invention discloses a traffic incident detection method based on intelligent spikes, and relates to the technical field of intelligent highway traffic incident detection. The intelligent spikes are arranged at fixed intervals according to numbers and the road direction; collecting a background magnetic field initial reference value of a set position, and obtaining an initial reference value vector sum; detecting the real-time magnetic field intensity when the vehicle passes, obtaining the real-time magnetic field intensity vector sum, and obtaining the magnetic field change value of the magnetic field at the position where the intelligent spike is arranged under the influence of the vehicle through the real-time magnetic field intensity vector sum and the initial reference value vector sum; calculating the passing speed of the vehicle according to the fixed interval of the adjacent intelligent spikes and the time of the vehicle passing through the intelligent spikes determined by a fluctuation threshold value generated by the influence of the preset vehicle on the earth magnetic field; and according to the number, the road driving direction, the fixed interval, the vehicle speed, the change value, the fluctuation threshold value and a preset speed threshold value, carrying out traffic event judgment. According to the invention, the detection precision is improved, and the construction fund is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent highway traffic incident detection, and more particularly to a traffic incident detection method based on intelligent road spikes. Background Art

[0002] Traffic incident detection, as one of the important technologies of intelligent transportation system, plays a vital role in alleviating traffic congestion, improving traffic safety and ensuring travel efficiency. Timely, accurate and effective detection of road traffic incident information is the basis of highway operation management, which will directly affect the level of road emergency control, traffic safety warning and driving guidance strategy and traffic information release service level.

[0003] However, since traffic events themselves are highly random and the road traffic environment is highly complex and changeable, the difficulty of accurately detecting traffic events is increased.

[0004] There are still some problems in the current highway traffic incident information perception and collection technology, mainly reflected in the fact that the detection equipment is mostly based on roadside sensing means such as high-definition cameras, millimeter-wave radars, integrated radar and lidar. These devices need to be installed on poles, which are relatively expensive, have large layout spacings, and lack continuity, which can easily lead to detection blind spots, and cannot accurately detect traffic event information on the entire road section and lanes.

[0005] Therefore, how to make accurate and rapid judgments on traffic incidents is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0006] In view of this, the present invention provides a traffic incident detection method based on intelligent road studs. Intelligent road studs integrate the collection, communication and release of traffic information and are buried on the road surface at certain intervals along the road lanes. In terms of collection, the intelligent road studs have built-in three-axis geomagnetic sensors. Compared with cameras, radars and other equipment, they have the characteristics of a wide variety of collection parameters, low manufacturing costs, simple installation and maintenance, strong environmental adaptability, and no influence from bad weather. The use of traffic incident detection methods based on intelligent road studs can enhance the continuity range of highway traffic incident detection, reduce detection costs, improve the cost-effectiveness of road electromechanical system construction, and achieve high-precision, all-weather traffic incident detection capabilities.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A method for detecting traffic incidents based on intelligent road spikes comprises: numbering a plurality of intelligent road spikes and arranging them in sequence at fixed intervals according to a specified road driving direction; collecting an initial reference value of a background magnetic field at a set position by means of the energized intelligent road spikes, and obtaining an initial reference value vector sum according to the initial reference value; using the intelligent road spikes to detect the real-time magnetic field intensity when a vehicle passes by, further obtaining a real-time magnetic field intensity vector sum, and obtaining a change value of the magnetic field intensity caused by the magnetic field at the set position of the intelligent road spikes being affected by the vehicle by means of the real-time magnetic field intensity vector sum and the initial reference value vector sum; calculating the speed of the vehicle passing by means of a fixed interval between two adjacent intelligent road spikes and a time when the vehicle passes by the intelligent road spikes determined by a preset fluctuation threshold value generated by the vehicle's influence on the earth's magnetic field; and determining a traffic incident according to the number, road driving direction, fixed interval, vehicle speed, change value, fluctuation threshold value and preset speed threshold value.

[0009] Preferably, the obtaining of the initial reference value vector and the specific method include collecting the background magnetic field of the surrounding environment to generate the initial reference value B after the smart road stud is powered on. x-base , B y-base , B z-base , perform vector sum calculation on the three-dimensional data to obtain the reference value vector sum, as shown in the following formula:

[0010]

[0011] In the formula, B x-base , B y-base , B z-base They respectively represent the initial reference values ​​of the background magnetic field data, and x, y, and z represent different directions in three-dimensional space.

[0012] Preferably, the change value of the magnetic field strength specifically includes:

[0013] The intelligent road stud is used to detect the real-time magnetic field strength B when a vehicle passes by. x1 , B y1 , B z1 , further obtain the real-time magnetic field intensity vector and

[0014] The change value ΔB of the magnetic field strength caused by the magnetic field at the location where the smart road spike is set due to the influence of the vehicle is obtained by using the real-time magnetic field strength vector sum and the initial reference value vector sum,

[0015] Preferably, the time when the vehicle passes through the smart road stud specifically includes:

[0016] When the change value ΔB is greater than the fluctuation threshold B thWhen , it is considered that a vehicle has arrived at the detection point. At this time, the start time of the vehicle passing the detection point is recorded;

[0017] When the vehicle passes, the change value ΔB gradually decreases, and when ΔB is less than the fluctuation threshold B th And when it is within the allowable range of the reference value error, it is considered that the vehicle leaves the detection point. At this time, the departure time of the vehicle passing the detection point is recorded, and the time interval between the start time and the departure time is the vehicle passing time T.

[0018] Preferably, the calculating of the speed of the vehicle passing by specifically includes:

[0019] v=S / (T 1 -T 2 );

[0020] Among them, T 1 is the time to pass the first smart spike, T 2 is the time it takes to pass the second smart road stud, S is the fixed interval between the first and second smart road studs, v is the speed at which the vehicle passes, and the positive or negative value of the speed represents the direction in which the vehicle is traveling.

[0021] Preferably, the traffic events include parking events, wrong-way events, and congestion events.

[0022] Preferably, the judgment criterion for the parking event is: when a vehicle arrives at the detection point, the change value is greater than the fluctuation threshold, that is, after the determination of the arrival of the vehicle is detected, the recorded time for the vehicle to pass the detection point exceeds the preset time and the change value is greater than the fluctuation threshold, and the vehicle still does not leave the detection point, it means that the vehicle is parked at the detection point.

[0023] Preferably, the judgment standard of the wrong-way event is: after detecting the numbered smart road studs installed in sequence at fixed intervals according to the specified road driving direction, when n consecutive road studs from the smart road stud with small numbers to the smart road stud with large numbers detect that the speed of n-1 vehicles passing by is negative, it is determined to be a wrong-way event.

[0024] Preferably, the judgment standard of the parking event is: intelligent road studs are installed at regular intervals on the road, and when 10 consecutive intelligent road studs detect that 90% of the absolute values ​​of vehicle speeds are lower than a preset speed threshold, it is determined to be a congestion event.

[0025] Preferably, the method further includes initializing the smart road stud after being powered on.

[0026] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a traffic incident detection method based on intelligent road studs, which, on the one hand, will effectively improve the detection accuracy of road traffic incident information; on the other hand, compared with roadside sensing equipment methods such as radar and video, it can save a lot of construction capital costs. In addition, the research and development of the present invention will make the intelligent road studs an intelligent road test device that integrates perception and early warning, and has multiple functions of information perception and release, which is not available in most current smart highway equipment. The application of the present invention will effectively improve the driving safety and intelligence level of roads, and improve operational efficiency and travel service experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0028] Figure 1 A flow chart of traffic incident detection provided by the present invention;

[0029] Figure 2 This is a schematic diagram of the deployment of the intelligent road spikes provided by the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Smart road studs mainly detect vehicles through three-axis geomagnetic sensors. Based on the fact that magnetic fields can be affected by ferromagnetic metals (generally iron, cobalt, nickel, etc.), three-axis geomagnetic sensors can detect vehicles containing ferromagnetic metals by detecting changes in the earth's magnetic field. Through analog-to-digital conversion, it is converted into a digital quantity that is easy to calculate to represent the local earth's magnetic field strength.

[0032] The embodiment of the present invention discloses a traffic incident detection method based on intelligent road studs, such as Figure 1 As shown, it includes: numbering a plurality of intelligent road studs and arranging them in sequence at fixed intervals according to the specified road driving direction, such as Figure 2As shown; the background magnetic field initial reference value of the setting position is collected by the powered-on smart road stud, and the initial reference value vector sum is obtained according to the initial reference value; the real-time magnetic field strength when the vehicle passes by is detected by the smart road stud, and the real-time magnetic field strength vector sum is further obtained, and the change value of the magnetic field strength caused by the magnetic field at the setting position of the smart road stud affected by the vehicle is obtained by the real-time magnetic field strength vector sum and the initial reference value vector sum; the speed of the vehicle passing is calculated according to the fixed interval between two adjacent smart road studs and the time when the vehicle passes the smart road stud determined by the fluctuation threshold generated by the influence of the vehicle on the earth's magnetic field; the traffic event is judged according to the number, road driving direction, fixed interval, vehicle speed, change value, fluctuation threshold and preset speed threshold.

[0033] Among them, through a large number of experiments, the threshold B of the fluctuation of the vehicle's influence on the earth's magnetic field was obtained. th ,The threshold can be adjusted according to the sensitivity and other requirements;

[0034] In a specific embodiment, the fixed interval is 15 meters.

[0035] In a specific embodiment, obtaining the initial reference value vector and specifically including collecting the background magnetic field of the surrounding environment after the smart road stud is powered on to generate the initial reference value B x-base , B y-base , B z-base , perform vector sum calculation on the three-dimensional data to obtain the reference value vector sum, as shown in the following formula:

[0036]

[0037] In the formula, B x-base , B y-base , B z-base They respectively represent the initial reference values ​​of the background magnetic field data, and x, y, and z represent different directions in three-dimensional space.

[0038] In a specific embodiment, the change value of the magnetic field strength specifically includes:

[0039] Intelligent road studs are used to detect the real-time magnetic field strength when vehicles pass by. x1 , B y1 , B z1 , further obtain the real-time magnetic field intensity vector and

[0040] The change value ΔB of the magnetic field intensity caused by the influence of the vehicle on the magnetic field at the location where the smart road spike is set is obtained by comparing the real-time magnetic field intensity vector and the initial reference value vector.

[0041] In a specific embodiment, the time when a vehicle passes through a smart road stud specifically includes:

[0042] When the change value ΔB is greater than the fluctuation threshold B th When , it is considered that a vehicle has arrived at the detection point. At this time, the start time of the vehicle passing the detection point is recorded;

[0043] When the vehicle passes, the change value ΔB gradually decreases. When ΔB is less than the fluctuation threshold B th And when it is within the allowable range of the reference value error, it is considered that the vehicle leaves the detection point. At this time, the departure time of the vehicle passing the detection point is recorded, and the time interval between the start time and the departure time is the vehicle passing time T.

[0044] In a specific embodiment, calculating the speed of a vehicle passing by specifically includes:

[0045] v=S / (T 1 -T 2 );

[0046] Among them, T 1 is the time to pass the first smart spike, T 2 is the time it takes to pass the second smart road stud, S is the fixed interval between the first and second smart road studs, v is the speed at which the vehicle passes, and the positive or negative value of the speed represents the direction in which the vehicle is traveling.

[0047] Smart road studs are installed on both sides of the lane, one between every two dotted lines, and one every 15 meters. Vehicle speed detection based on smart road studs requires two road studs installed at 15-meter intervals to jointly determine.

[0048] In a specific embodiment, the traffic events include parking events, wrong-way events, and congestion events.

[0049] In a specific embodiment, the judgment criteria for a parking event are: when a vehicle arrives at a detection point, the change value is greater than a fluctuation threshold, that is, after the determination that a vehicle has arrived is detected, the recorded time for the vehicle to pass the detection point exceeds a preset time and the change value is greater than the fluctuation threshold, and the vehicle still has not left the detection point, it indicates that the vehicle is parked at the detection point.

[0050] In a specific embodiment, the judgment standard of the wrong-way event is: after detecting the numbered smart road studs installed in sequence at fixed intervals according to the specified road driving direction, when n consecutive road studs from the small-numbered smart road studs to the large-numbered smart road studs detect that the speed of n-1 vehicles passing by is negative, it is determined to be a wrong-way event.

[0051] In one specific embodiment, n is 4 (60 meters distance).

[0052] In a specific embodiment, the judgment standard of the parking event is: the road is installed with smart road studs at regular intervals, and when 10 consecutive smart road studs (150 meters apart) detect that the absolute values ​​of the speeds of 90% of the vehicles are lower than the preset speed threshold V 0 (generally 30km / h, and a reasonable congestion speed threshold can be formulated based on the actual road conditions) is determined as a congestion event.

[0053] In a specific embodiment, the method further includes initializing the powered-on smart road studs, wherein the initialization includes: finding a roadside controller wireless network, networking multiple smart road stud wireless networks, clearing an internal buffer of the device, collecting external earth magnetic field background, and preprocessing vehicle detection.

[0054] In a specific embodiment, when a traffic event is detected, the smart road stud transmits the event information to the roadside smart road stud controller via a wireless network, and the controller uploads the traffic event information to a central monitoring platform via a fiber optic network.

[0055] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0056] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A traffic incident detection method based on intelligent road studs, characterized in that: include: A plurality of intelligent road studs are numbered and arranged in sequence at fixed intervals according to a specified road driving direction; an initial reference value of a background magnetic field at a set position is collected by the energized intelligent road stud, and an initial reference value vector sum is obtained according to the initial reference value; the real-time magnetic field strength when a vehicle passes by is detected by the intelligent road stud, and a real-time magnetic field strength vector sum is further obtained, and a change value of the magnetic field strength caused by the magnetic field at the set position of the intelligent road stud affected by the vehicle is obtained by the real-time magnetic field strength vector sum and the initial reference value vector sum; the speed of the vehicle passing through is calculated according to the fixed interval between two adjacent intelligent road studs and the time when the vehicle passes through the intelligent road stud determined by a preset fluctuation threshold generated by the vehicle's influence on the earth's magnetic field; and a traffic event is judged according to the number, road driving direction, fixed interval, vehicle speed, change value, fluctuation threshold and preset speed threshold.

2. The method for detecting traffic incidents based on intelligent road studs according to claim 1, characterized in that: The obtaining of the initial reference value vector and the specific method include collecting the background magnetic field of the surrounding environment to generate the initial reference value B after the intelligent road stud is powered on. x-base , B y-base , B z-base , perform vector sum calculation on the three-dimensional data to obtain the reference value vector sum, as shown in the following formula: In the formula, B x-base , B y-base , B z-base They respectively represent the initial reference values ​​of the background magnetic field data, and x, y, and z represent different directions in three-dimensional space.

3. The method for detecting traffic incidents based on intelligent road studs according to claim 2, characterized in that: The change value of the magnetic field strength specifically includes: The intelligent road stud is used to detect the real-time magnetic field strength B when a vehicle passes by. x1 , B y1 , B z1 , further obtain the real-time magnetic field intensity vector and The change value ΔB of the magnetic field strength caused by the magnetic field at the location where the smart road spike is set due to the influence of the vehicle is obtained by using the real-time magnetic field strength vector sum and the initial reference value vector sum, 4. The method for detecting traffic incidents based on intelligent road studs according to claim 3, characterized in that: The time when the vehicle passes through the smart road stud specifically includes: When the change value ΔB is greater than the fluctuation threshold B th When , it is considered that a vehicle has arrived at the detection point. At this time, the start time of the vehicle passing the detection point is recorded; When the vehicle passes, the change value ΔB gradually decreases, and when ΔB is less than the fluctuation threshold B th And when it is within the allowable range of the reference value error, it is considered that the vehicle leaves the detection point. At this time, the departure time of the vehicle passing the detection point is recorded, and the time interval between the start time and the departure time is the vehicle passing time T.

5. The method for detecting traffic incidents based on intelligent road studs according to claim 1, characterized in that: The calculation of the speed at which the vehicle passes specifically includes: v = S / (T1 - T2); Among them, T1 is the time of passing the first smart road stud, T2 is the time of passing the second smart road stud, S is the fixed interval between the first smart road stud and the second smart road stud, v is the speed of the vehicle passing, and the positive or negative speed represents the direction of the vehicle.

6. The method for detecting traffic incidents based on intelligent road studs according to claim 1, characterized in that: The traffic events include parking events, wrong-way events, and congestion events.

7. The method for detecting traffic incidents based on intelligent road studs according to claim 6, characterized in that: The judgment standard of the parking event is: when a vehicle arrives at the detection point, the change value is greater than the fluctuation threshold, that is, after the determination of the arrival of the vehicle is detected, the recorded time of the vehicle passing the detection point exceeds the preset time and the change value is greater than the fluctuation threshold, and the vehicle still does not leave the detection point, it means that the vehicle is parked at the detection point.

8. The method for detecting traffic incidents based on intelligent road studs according to claim 6, characterized in that: The judgment standard of the wrong-way event is: after detecting the numbered smart road studs installed in sequence at fixed intervals according to the specified road driving direction, when n consecutive road studs from the smart road stud with small numbers to the smart road stud with large numbers detect that the speed of n-1 vehicles passing by is negative, it is determined to be a wrong-way event.

9. The method for detecting traffic incidents based on intelligent road studs according to claim 6, characterized in that: The judgment standard of the parking event is: intelligent road studs are installed at regular intervals on the road, and when 10 consecutive intelligent road studs detect that the absolute values ​​of 90% of the vehicle speeds are lower than a preset speed threshold, it is determined as a congestion event.

10. The method for detecting traffic incidents based on intelligent road studs according to claim 1, characterized in that: It also includes initializing the smart road studs after they are powered on.

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