CN202615608U - Road vehicle information collection node device based on laser rangefinding - Google Patents

Abstract

The utility model relates to a road vehicle information collection node device based on laser ranging, which includes a laser distance sensor and a data processor built in the laser distance sensor. The node device is erected above a lane on the road, and the laser distance The sensor adopts a large-angle laser transceiver ranging sensor, and the data processor has a vehicle information identification module, which is connected to the laser distance sensor and the external road control system server. Utilizing the node device of the present utility model, the data processor can realize vehicle speed measurement, vehicle behavior triggering, vehicle contour drawing, traffic flow statistics, etc. Many functions, and the road vehicle information collection node device based on laser ranging of the utility model has a simple structure, simple layout and application, low cost, good application effect, good application scalability, and a wide range of applications.

Description

Road Vehicle Information Acquisition Node Device Based on Laser Ranging

technical field

The utility model relates to traffic information collection equipment, in particular to laser equipment for traffic information collection, in particular to a road vehicle information collection node device based on laser distance measurement.

Background technique

Laser distance sensor (also known as laser rangefinder) is an instrument that uses laser to accurately measure the distance of the target. The laser distance sensor relies on the reflection of the target to identify: the sensor emits a pulsed laser to the target, the photoelectric element receives the laser pulse reflected by the target, and the time discrimination measures the pulse flight time of the laser beam from emission to reception, and the distance from the sensor to the target can be obtained. distance. The laser radar developed on the basis of the laser distance sensor can not only measure the distance, but also measure the target orientation, movement speed and acceleration. Laser distance sensor is a comprehensive application of multidisciplinary technologies such as laser, precision machinery, embedded technology and optoelectronics. Because the laser has the advantages of high directivity, high monochromaticity and high power, the application field of the laser distance sensor is constantly expanding due to the advantages of long distance measurement, convenient determination of target orientation, high accuracy and resolution, and strong anti-interference ability. The needs of the industry are numerous.

The reason why intelligent transportation has huge development potential and has become a key area of the development of the Internet of Things is inseparable from my country's national conditions. With the vigorous development of my country's economic construction, the scale of cities continues to expand, the number of cars continues to grow rapidly, traffic congestion is becoming more and more serious, and traffic accidents occur from time to time. Traffic problems have become a major social problem in urban management. It is very important to use advanced electronics, communication and other technologies to develop my country's intelligent transportation system, strengthen the transportation management of existing road traffic, and improve the traffic capacity and traffic service quality of the road network.

At present, my country's highway traffic information collection mainly includes monitoring methods such as ground sensing coils, microwave detection, ultrasonic detection, video image recognition, and piezoelectric weighing, all of which have their own limitations. For example, the effect is single, and a set of instruments can only detect a single traffic information feature; the detection accuracy is not high, and when there are vehicles that are close to each other or obstruct each other, part of the vehicle speed and flow information will be lost or misjudged; the cost is high , The construction is troublesome, such as the ground sense coil needs to be buried on the road in advance, and the cost of the video analysis server has been high.

In the relevant application fields of using laser technology for traffic information collection, Chinese patent application 200810079778.0 discloses a laser information collection that uses infrared light sensors to cooperate with paved reflective tape on the road surface, and scans point by point along the length of the reflective tape. The device, two groups of such infrared light sensors are located at a distance of d, and can measure the length, driving speed, etc. of the vehicle. However, this type of information collection has many disadvantages, such as the need to use two sets of light sensor systems; the need to set reflective tape on the road; if the desired effect of this patent is to be achieved, the sensor needs to scan back and forth at a speed of hundreds or even It is difficult to achieve a mechanical scanning structure with such a scanning range of up to kilohertz. Chinese patent application 200910092596.1 introduces a method of monitoring road vehicles using a laser rangefinder or ultrasonic rangefinder placed vertically on the road surface, which can achieve the purpose of identifying the type of road vehicle and monitor the distance change point during identification. However, this patent The sampling rate of the method for vehicle identification is low, and the vehicle cannot be carefully screened; another shortcoming of this patent is that because this patent does not consider the influence of the speed of the vehicle on the sampling rate of the vehicle height point, the recognition rate of the vehicle type Very low, less effective application.

Utility model content

The purpose of this utility model is to overcome the shortcomings of the above-mentioned prior art, and provide a vehicle speed measurement, vehicle behavior trigger, vehicle outline drawing, traffic flow statistics and many other functions, with simple structure, convenient layout and application, and low cost. A road vehicle information collection node device based on laser distance measurement that is cheap, has good application effects, and has a wide range of applications.

In order to achieve the above-mentioned purpose, the road vehicle information collection node device based on laser ranging of the present invention has the following composition:

The node device includes a laser distance sensor and a data processor built in the laser distance sensor, the node device is erected above a lane of the road, and the laser distance sensor is a large-angle laser transceiver ranging sensor, The data processor has a vehicle information identification module, and the signal output end of the laser distance sensor is connected to the signal input end of the vehicle information identification module.

In the road vehicle information collection node device based on laser ranging, the large-angle laser transceiver ranging sensor includes a control circuit, a pulsed laser transmitting circuit and a laser receiving circuit, and the pulsed laser transmitting circuit and the laser receiving circuit are connected to The control circuit, the control circuit is also connected to the data processor.

In the road vehicle information collection node device based on laser ranging, the laser emission direction of the pulsed laser emission circuit faces the incoming vehicle direction of the lane, and the angle between the laser emission direction and the lane is within 20 ° to 60°.

In the road vehicle information collection node device based on laser ranging, the receiving aperture angle of the large-angle laser transceiver ranging sensor is between 20 milliradians and 100 milliradians.

In the road vehicle information collection node device based on laser ranging, the receiving range of the laser receiving circuit is a circular range with a diameter of 2.7 meters.

In the road vehicle information collection node device based on laser ranging, the data processor also includes a time signal receiving end and a signal processing module, and the output end of the laser distance sensor passes through the time signal receiving end and the signal processing module. The processing module is connected to the vehicle information identification module.

In the road vehicle information collection node device based on laser ranging, the vehicle information identification module includes a trigger judgment unit, a vehicle speed judgment unit, and a vehicle type identification unit, and the outputs of the trigger judgment unit, vehicle speed judgment unit, and vehicle type identification unit are All terminals are connected to an external road control system or server.

Adopting the road vehicle information collection node device based on laser distance measurement of the utility model, it includes a laser distance sensor and a data processor built in the laser distance sensor, the node device is erected above a lane on the road, The laser distance sensor adopts a large-angle laser transceiver ranging sensor, and the data processor has a vehicle information identification module, and the vehicle information identification module is connected to the laser distance sensor, and can utilize distance measurement data, thereby realizing many functions such as vehicle speed measurement, vehicle behavior triggering, vehicle outline drawing, traffic flow statistics, etc., and the road vehicle information collection node device based on laser distance measurement of the utility model is simple in structure, convenient in layout and application, The cost is low, the application effect is good, the application scalability is good, and the application range is relatively wide.

Description of drawings

Fig. 1 is a schematic diagram of the application mode of the road vehicle information collection node device based on laser ranging of the present invention.

Fig. 2 is a schematic diagram of the principle of the road vehicle information collection node device based on laser ranging according to the present invention.

Fig. 3 is an effect diagram of scanning and identifying a small car by using the road vehicle information collection node device based on laser ranging of the utility model.

Fig. 4 is an effect diagram of scanning and identifying taxis using the road vehicle information collection node device based on laser ranging of the utility model.

Fig. 5 is an effect diagram of scanning and identifying container trucks by using the road vehicle information collection node device based on laser ranging of the utility model.

Fig. 6 is an effect diagram of scanning and identifying a truck by using the road vehicle information collection node device based on laser ranging of the utility model.

Fig. 7 is an effect diagram of scanning and identifying a mixer truck by using the road vehicle information collection node device based on laser ranging of the utility model.

Detailed ways

In order to understand the technical content of the present utility model more clearly, the following examples are given in detail.

Please refer to FIG. 1 , which is a schematic diagram of the application mode of the road vehicle information collection node device based on laser ranging of the present invention.

The road vehicle information collection node device 1 based on laser ranging of the present invention is erected on the upper gantry 2 of a lane on the road 6, and is connected to the server 4 of the external road control system through a cable 5 . In one embodiment, the node device 1 includes a laser distance sensor and a data processor built in the laser distance sensor. The laser distance sensor is a large-angle laser transceiver ranging sensor, as shown in Figure 2, the large-angle laser transceiver ranging sensor includes a control circuit, a pulsed laser emitting circuit and a laser receiving circuit, the pulsed laser emitting circuit and The laser receiving circuits are all connected to the control circuit, and the control circuit is also connected to the data processor. The data processor has a vehicle information identification module, and the signal output end of the laser distance sensor is connected to the signal input end of the vehicle information identification module.

In a more preferred embodiment, the laser emission direction of the pulsed laser emission circuit faces the direction of the vehicle on the lane (as shown by the arrow in Figure 1), and the laser emission direction is in the same direction as the lane between the lanes. The angle of the corners is between 20° and 60°. The laser emitted by the pulsed laser emitting circuit forms a rectangular spot 3 of 2.5 meters by 1 meter on the said lane. The distance between the light spot 3 and the laser distance sensor is 25 meters.

In another preferred embodiment, the receiving aperture angle of the large-angle laser transceiver ranging sensor is between 20 milliradians and 100 milliradians. The receiving range of the laser receiving circuit is a circular range with a diameter of 2.7 meters.

In a more preferred embodiment, the data processor also includes a time signal receiving end and a signal processing module, and the output end of the laser distance sensor is connected to the described time signal receiving end and the signal processing module. Vehicle information identification module. The vehicle information identification module includes a trigger judging unit, a vehicle speed judging unit and a vehicle type identification unit, and the output ends of the trigger judging unit, vehicle speed judging unit and vehicle type identification unit are all connected to an external road control system or server.

In practical applications, unlike previous patents or products that can only collect a single traffic information, the utility model provides a miniaturized and node-based solution based on the Internet of Things. A laser ranging node can realize a laser intelligent traffic information collection node including vehicle speed measurement, vehicle behavior triggering, vehicle outline drawing, traffic flow statistics and many other functions. This intelligent transportation node can output the trigger signal of the arrival of the vehicle, and provide a time trigger signal for photo evidence collection or video processing; and can output the speed of the road vehicle and the outline of the vehicle in real time. A set of nodes is arranged on one bayonet to form a system, which can have a comprehensive understanding of vehicle information on this road, such as congestion, traffic conditions, and vehicle model distribution. Described technical scheme is as follows:

When in use, the laser is emitted from the top of the bayonet pole or on the gantry at a certain angle to the direction of the incoming vehicle of a single lane. This angle can ensure that the sensor node can measure the vehicle speed without causing the vehicle model to scan the outline. Too blurry (recommend setting an inclination between 20 and 60 degrees to the ground). The scan profile obtained in this way combined with the speed information of the vehicle can make an accurate judgment on the vehicle type. The laser adopts a large-angle transmission and reception method, so that the distance measuring device can basically cover a lane when the beam reaches the road at a certain angle above the gantry or pole, which can effectively prevent the occurrence of false alarms in vehicle detection.

The intelligent traffic information collection node is a miniaturized high-precision high-repetition frequency laser distance sensor, which can output distance data streams and some data processing results in real time, such as vehicle types, trigger signals, and vehicle speeds. The laser of the rangefinder adopts a large angle of emission and reception, and makes appropriate corrections to the shape of the spot, so that the emitted laser is a spot of about 2.5 meters x 1 meter at a distance of 25 meters. The accuracy of the rangefinder is less than 1cm, and the pulse repetition frequency is greater than 1k Hz.

The plurality of intelligent transportation information collection nodes constitute a complete coverage of a road surface, and the data of these sensor nodes are connected to the data analysis server through the transmission line to provide data and service support for the intelligent transportation network.

When the vehicle arrives, the previous set of data obtained by the sensor node first detects the change of the distance and judges whether it is a vehicle or an interference signal, and then sends a trigger signal to the background camera or host to indicate the arrival of the vehicle. Calculate the speed of the vehicle according to the change of the measured distance signal, store a complete vehicle profile information, compare and identify the type of the vehicle combined with the vehicle speed, and obtain the vehicle model information. The trigger signal of a bayonet or a sensor node of a complete lane, vehicle speed and model information are transmitted to the bayonet control box or server in the background, and the traffic information of the entire road is synthesized.

Specifically, as shown in Figure 1: a ranging node is placed on each lane of the road, and it is erected at an angle of 20 degrees to 60 degrees facing the direction of the arrival of the car; the ranging nodes are set up according to a certain frequency (≥ 1KHz) to the road (about 25 meters away) to emit ranging laser pulses to monitor the vehicles passing through the lane, so that the vehicle body with a speed of 200Km/h can measure a point every 5cm, which can ensure the effective depiction of the vehicle outline; The distance measuring node laser adopts a large-angle emission and receiving method, forming a light spot of about 2.5m×1m on the road surface, which is our information collection and detection area; when the vehicle arrives, the detection node first judges according to a set of distance changes When the vehicle arrives, it transmits a signal to other linkage sensing devices such as cameras to transmit a trigger pulse. The response time of the arrival of the vehicle is very short, about 10 milliseconds; when the license plate of the vehicle enters the detection area, the comprehensive A component of vehicle travel speed in the direction of the laser is considered by the formula:

$\mathrm{<span\; class="notranslate">\; V</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&Delta;D</span>}}{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; cos</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}}$

Where θ is the angle between the laser direction and the road surface, from which the speed V of the vehicle can be calculated; when the vehicle passes through completely, the vehicle profile can be restored by comprehensively measuring the angle θ and the vehicle speed V according to the distance change measured by the ranging node. The height can be reduced to:

h=H-Dsinθ

Among them, H is the height of the ranging node from the ground. Therefore, the h value and the speed V can describe the contour characteristics of the vehicle. By comparing and identifying the obtained vehicle contour characteristics with the sample vehicle appearance characteristics, the passing vehicle can be obtained. type. As shown in Fig. 3 to Fig. 7, the characteristic effect of the vehicle outline after scanning and identifying small cars, taxis, container trucks, trucks and mixer trucks using the utility model road vehicle information collection node device based on laser ranging In the figure, the abscissa in the figure is 50 points/grid, and the ordinate is 0.6m/grid. The determined vehicle type information can be obtained by comparing the vehicle profile feature map with the preset vehicle model library data in the node device.

The vehicles of all bayonet sensor nodes are sent to the background through information trigger count, vehicle speed, vehicle type and other information for data analysis, and can obtain the overall road surface traffic flow, congestion situation, vehicle distribution and other information, and cooperate with other information collection methods such as cameras , can have a more comprehensive and intuitive understanding of road conditions, and provide a basis for traffic guidance, vehicle supervision, and information release.

In the technical scheme of the road vehicle information collection node device based on laser ranging of the present invention, each functional module and module unit included therein can correspond to specific hardware circuits in the integrated circuit structure, so these modules and units only use The hardware circuit structure can be realized, and the corresponding functions can be automatically realized without the assistance of specific control software.

And the utility model includes the following features:

1. It can use infrared light as the detection medium, and can collect traffic information all-weather without being affected by ambient light;

2. There is no need to construct the road surface or lay cooperation targets, and compared with the ground sense coil, it can judge the arrival time of the vehicle more accurately;

3. It can realize the speed measurement of vehicles in a single lane, reduce the interference of vehicles between different lanes, avoid false positives and missed negatives of vehicle information, and facilitate the capture and identification of lanes. Provide valid evidence;

4. Only a single sensor node is needed to detect a large number of traffic information, the overall cost is low, and it is suitable for the layout of high-density detection points;

5. The front-end traffic information node has the characteristics of intelligent processing, which can detect basic information such as vehicle speed and vehicle type. Based on the advantages of the front-end functional node, it can realize multi-node networking, so that it can make a comprehensive analysis of the information of the entire road.

Adopting the road vehicle information collection node device based on laser distance measurement of the utility model, it includes a laser distance sensor and a data processor built in the laser distance sensor, the node device is erected above a lane on the road, The laser distance sensor adopts a large-angle laser transceiver ranging sensor, and the data processor has a vehicle information identification module, and the vehicle information identification module is connected to the laser distance sensor, and can utilize distance measurement data, thereby realizing many functions such as vehicle speed measurement, vehicle behavior triggering, vehicle outline drawing, traffic flow statistics, etc., and the road vehicle information collection node device based on laser distance measurement of the utility model is simple in structure, convenient in layout and application, The cost is low, the application effect is good, the application scalability is good, and the application range is relatively wide.

In this specification, the invention has been described with reference to specific embodiments thereof. However, it is obvious that various modifications and changes can be made without departing from the spirit and scope of the present invention. Accordingly, the specification and drawings are to be regarded as illustrative rather than restrictive.

Claims (7)

1. road vehicle information acquisition node apparatus based on laser ranging; It is characterized in that; Described node apparatus comprises laser distance sensor and is built in the data processor in the described laser distance sensor; Described node apparatus is set up in the top in a track of road; Described laser distance sensor is a wide-angle laser transmitting-receiving distance measuring sensor, and described data processor has the information of vehicles identification module, and the signal output part of described laser distance sensor connects the signal input part of described information of vehicles identification module.

2. the road vehicle information acquisition node apparatus based on laser ranging according to claim 1; It is characterized in that; Described wide-angle laser transmitting-receiving distance measuring sensor comprises control circuit, pulse laser radiating circuit and laser pick-off circuit; Described pulse laser radiating circuit all is connected described control circuit with the laser pick-off circuit, and described control circuit also connects described data processor.

3. the road vehicle information acquisition node apparatus based on laser ranging according to claim 2; It is characterized in that; The Laser emission direction of described pulse laser radiating circuit is met the direction to the car to the track, place, and between described Laser emission direction and track the angle of angle between 20 ° to 60 °.

4. the road vehicle information acquisition node apparatus based on laser ranging according to claim 2 is characterized in that the receiving aperture angle of described wide-angle laser transmitting-receiving distance measuring sensor is between 20 milliradian to 100 milliradians.

5. the road vehicle information acquisition node apparatus based on laser ranging according to claim 2 is characterized in that the range of receiving of described laser pick-off circuit is the circular scope of 2.7 meters of diameters.

6. according to each described road vehicle information acquisition node apparatus in the claim 1 to 5 based on laser ranging; It is characterized in that; Described data processor also comprises time signal receiving end and signal processing module, and the output terminal of described laser distance sensor is connected described information of vehicles identification module through described time signal receiving end with signal processing module.

7. the road vehicle information acquisition node apparatus based on laser ranging according to claim 6; It is characterized in that; Described information of vehicles identification module comprises triggering judging unit, speed of a motor vehicle judging unit and vehicle recognition unit, and the output terminal of described triggering judging unit, speed of a motor vehicle judging unit and vehicle recognition unit all is connected outside road path control system or server.

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