JP3804404B2 - Vehicle detection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
This invention detects a vehicle running on a road, further relates to a vehicle detection device which measures the specifications of the vehicle height and vehicle width or the like of the vehicle.
[0002]
[Prior art]
If the vehicle traveling on the road is very heavy, it will damage the road, which contributes to shortening the road life. Further, when the vehicle is very heavy, it is known that the traveling performance such as changing the traveling direction of the vehicle or stopping the vehicle is low. Furthermore, it is known that driving a very large vehicle is difficult for the driver of the vehicle. These factors contribute to dangers such as traffic accidents.
[0003]
Large vehicles are generally known to be heavy. Therefore, a large vehicle is inspected to determine whether it is within a predetermined size, and only a vehicle that is within a predetermined size by the inspection is allowed to travel on the road.
[0004]
Therefore, an apparatus for measuring specifications such as the length, width, height, and shape of a vehicle has been developed. In particular, as the above device, the laser beam is scanned from above the road in the direction perpendicular to the traveling direction of the vehicle, and the reflected light intensity of the scanned laser beam and the time difference between the irradiation of the laser beam and the reception of the reflected light are measured. Thus, a laser type vehicle detection device having a function of calculating specifications of a vehicle traveling on a road is used. Patent applications relating to these are disclosed in JP-A-11-191196, JP-A-10-256607, JP-A-2000-20878, and the like.
[0005]
[Problems to be solved by the invention]
By the way, in the laser type vehicle detection device, in order to secure the received light amount of the reflected light reflected by the vehicle, the spot shape of the laser beam to be irradiated (the shape of the portion where the laser beam is effectively irradiated) is a circle of φ50 mm or more. Or oval shape. In addition, in order to measure the vehicle width with high accuracy without being influenced by the curvature of the vehicle side surface, the spot shape of the laser beam is long in the traveling direction of the vehicle and short in the direction perpendicular to the traveling direction of the vehicle. It is desirable. For the above reasons, the conventional laser type vehicle detection apparatus has an elliptical shape in which the spot shape of the laser beam to be irradiated is elongated in the traveling direction of the vehicle.
[0006]
However, when the road is irradiated with a laser beam and the vehicle on the road is detected from the amount of reflected light, the detection position where the vehicle is detected is the maximum in the direction of travel of the vehicle due to the difference in reflectance due to the difference in the color of the vehicle. In other words, the laser beam is shifted by the length in the vehicle traveling direction. And the shift | offset | difference of the detection position which detects this vehicle has caused the measurement precision, such as the length (henceforth a vehicle length) of the advancing direction of this vehicle, to fall. As described above, the conventional laser type vehicle detection device has an elliptical shape in which the spot shape of the irradiated laser beam is elongated in the vehicle traveling direction so that the vehicle width can be measured with high accuracy without being affected by the curvature of the vehicle side surface. Therefore, the vehicle length could not be measured accurately.
[0008]
The purpose of the invention This improves the positional accuracy of detecting a vehicle passing through a road, is to provide a vehicle detection apparatus which can measure the specifications of the vehicle with high accuracy.
[0010]
[Means for Solving the Problems]
Car both detection apparatus of this invention includes the following configurations in order to solve the above problems.
[0017]
( 1 ) First to third light emitting units that emit laser beams arranged in the width direction of the passage above the passage through which the vehicle passes;
A fourth light emitting unit that emits a laser beam attached above the passage that is a predetermined distance away in the vehicle passing direction than the first to third light emitting units;
The first to provided third respectively for each emission of the first to third scanning unit for scanning in the vertical direction emitted laser beam with respect to the passing direction of vehicles,
A fourth scanning unit that scans the laser beam emitted from the fourth light emitting unit in the vehicle passing direction;
Provided with each of the first to fourth scanning units, and first to fourth light receiving units for receiving reflected light of the scanned laser beam, and
The laser beam spot shape that will be emitted from the first light-emitting portion located at the center is an elongated shape in the scanning direction of the laser beam by the first scanning unit,
Elongated in a direction perpendicular to the spot shape of the second, and the laser beam that will be emitted from the third light emitting part, the scanning direction of the laser beam by each of the second and third scan portion located on both sides And
The spot shape of the laser beam emitted from the fourth light emitting unit is a shape elongated in a direction perpendicular to the scanning direction of the laser beam by the fourth scanning unit,
Emitted from the first light emitting portion, and a vehicle detector for detecting the presence or absence of a vehicle passing through the passage from the reflected light of the laser beam received by the first light receiving portion,
The emission time of the laser beam emitted from the second and third light emitting units, the reception time of the reflected light in the second and third light receiving units, and the laser beam in the second and third scanning units A vehicle width calculation unit that measures the side shape of the vehicle passing through the passage using the scanning angle and calculates the width of the vehicle;
Using the emission time of the laser beam emitted from the fourth light emitting unit, the reception time of the reflected light in the fourth light receiving unit, and the scanning angle of the laser beam in the fourth scanning unit, The laser beam emitted from the fourth light emitting unit at the timing when the vehicle detecting unit detects the rear end of the vehicle passing through the passing path while measuring the cross-sectional shape of the front surface of the passing vehicle. A vehicle length calculation unit that calculates the length of the vehicle passing through the passage from the distance to the vehicle front surface measured using
[0018]
In this configuration, the laser beam emitted from the first light emitting unit located at the center is scanned in a direction perpendicular to the passing direction of the vehicle, that is, in the width direction of the passing path, and the vehicle is more than the first light emitting unit. The laser beam emitted from the fourth light emitting unit provided at a predetermined distance in the passing direction is scanned in the passing direction of the vehicle. Further, since the elongated shape in the vertical direction of the laser beam spot shape is irradiated from the first light emitting portion to the passage direction of the vehicle, it is possible to improve the positional accuracy of detecting a vehicle passing through over-road .
In addition, the spot shape of the laser beam emitted from the fourth light emitting unit is similarly elongated in the direction perpendicular to the vehicle passing direction, so that the positional accuracy for detecting the vehicle passing through the passage is improved. Can be made. Further, since the laser beam emitted from the fourth light emitting unit is configured to scan in the passing direction of the vehicle, the cross-sectional shape of the front surface of the vehicle passing through the passage can be measured. Further, at the timing when the rear end of the vehicle is detected by the laser beam emitted from the first light emitting unit, from the distance to the vehicle front surface measured using the laser beam emitted from the fourth light emitting unit. The length of the vehicle passing through the passage can be calculated, and the measurement accuracy of the vehicle length can be improved.
[0019]
Moreover, the second, and the third laser beam spot shape which is emitted from the light emitting unit since the elongated shape in the passing direction of the vehicle located on both sides, without being affected by the curvature of the car sides, the side of the vehicle The shape and the vehicle width can be accurately measured.
[0020]
( 2 ) Use the emission time of the laser beam emitted from the first light emitting unit, the reception time of the reflected light at the light receiving unit, and the scanning angle of the laser beam at the first scanning unit to pass through the passage. A vehicle height calculation unit is provided for calculating the height of the running vehicle .
[0021]
In this configuration, the position accuracy of detecting a vehicle passing through the passage over the road is improved, also measuring the height of the vehicle performed with high accuracy.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a diagram showing a configuration of a vehicle detection system according to an embodiment of the present invention. The vehicle detection system of this embodiment uses four laser vehicle shape sensors 1 to 4 that scan the vehicle with a laser beam and measure the shape of the vehicle, and the measurement results of these laser vehicle shape sensors 1 to 4. And a dimension measurement calculation unit 5 for calculating vehicle specifications (vehicle width, vehicle height, vehicle length, shape, etc.). As shown in FIG. 1, the laser vehicle shape sensors 1 to 3 are attached to the first gantry 6 arranged on the road side by side in a direction perpendicular to the traveling direction of the vehicle. The gantry 6 is attached to a second gantry 7 disposed on a road that is a certain distance away from the gantry 6 in the traveling direction of the vehicle. The distance between the first gantry 6 and the second gantry 7 is the maximum vehicle length that can be measured by this vehicle detection system.
[0023]
Laser vehicle shape sensors 1 to 3 attached to the first gantry 6 scan laser light in a direction perpendicular to the traveling direction of a vehicle traveling on the road (hereinafter referred to as the vehicle width direction). is there. Specifically, the laser vehicle shape sensor 1 attached to the center of the first gantry 6 measures the shape of the vehicle upper surface and the vehicle height. On the other hand, the laser vehicle shape sensors 2 and 3 attached to both sides of the laser vehicle shape sensor 1 measure the shape of the vehicle side surface and the vehicle width, respectively. On the other hand, the laser vehicle shape sensor 4 attached to the second gantry 7 is attached to the center of the first gantry 6 by scanning the laser beam in the traveling direction of the vehicle traveling on the road. The vehicle length is measured in combination with the obtained laser vehicle shape sensor 1.
[0024]
Each of the laser vehicle shape sensors 1 to 4 has the configuration shown in FIG. The laser car shape sensors 1 to 4 include a control unit 10 that controls the operation of the main body, a laser diode 11 (LD11) that emits a laser beam, and a laser beam emitted from the laser diode 11 that is condensed into a parallel beam. And a polygon mirror 13 that reflects the laser beam condensed by the light projecting lens 12 and scans it on the road. The laser diode 11 emits pulses at a predetermined cycle. The mirror 14 shown in FIG. 2 guides the laser beam that has passed through the light projecting lens 12 to the polygon mirror 13, and the laser beam reflected by the polygon mirror 13 is irradiated onto the road via an optical window.
[0025]
The polygon mirror 13 is driven to rotate at a constant speed by a motor (not shown), and the rotation angle of the polygon mirror 13 is detected by the encoder 15. Each of the laser wheel sensors 1 to 4 includes an LD driver 16 that causes the laser diode 11 to emit light at a predetermined cycle, and a laser power monitor 17 that detects the power of the laser beam emitted from the laser diode 11. . The laser beam emitted from the laser diode 11 must be kept at a level that is safe for the eyes of the driver. Therefore, the power is constantly monitored by the laser power monitor 17 and the emission of the laser beam is stopped when abnormal output occurs. To do.
[0026]
Furthermore, a light receiving lens 21 that condenses the laser beam reflected by the road surface or a running vehicle, and a photodiode 22 that receives the laser beam condensed by the light receiving lens 21 and converts it into an electrical signal are provided. . The photodiode 22 is an avalanche photodiode (APD), and as is well known, since the multiplication factor greatly changes with respect to the temperature change, a temperature compensation circuit 23 for monitoring the temperature of the photodiode 22 and performing temperature compensation is provided. ing. The output of the photodiode 22 is subjected to I / V conversion by the I / V conversion circuit 24, and after the noise component is removed by the anti-pass filter (BPF) 25, it is amplified by the amplifier 26. The signal amplified by the amplifier 26 is input to a time difference detection unit 27 that detects a time difference between the laser beam emitted from the laser diode 11 and the laser beam received by the photodiode 22. A signal indicating the light emission timing of the laser diode 11 is input from the LD driver 16 to the time difference detection unit 27.
[0027]
The measurement results measured by the vehicle measurement sensors 1 to 4 are input to the dimension measurement calculation unit 5, and the dimensions of the vehicle are calculated in the dimension measurement calculation unit 5.
[0028]
Hereinafter, the measurement operation | movement of the item of the vehicle by the vehicle detection system of this embodiment is demonstrated. As for the size of the vehicle, the maximum width, height and length, including the luggage loaded on the loading platform, are defined as the vehicle width, vehicle height and vehicle length, respectively. Since there are special vehicles as shown in FIG. 3, for example, in order to measure vehicle dimensions, the vehicle shape must be measured from the vehicle head to the vehicle tail. 3A is a top view of the vehicle, and FIG. 3B is a side view of the vehicle. Further, in FIG. 3, hatched portions are loads loaded on the loading platform.
[0029]
First, referring to FIG. 4, an operation for measuring the top surface shape and the vehicle height of a vehicle traveling on a road by the vehicle shape sensor 1 attached to the center of the first gantry 6 will be described. As described above, the vehicle shape sensor 1 scans the laser beam in a direction perpendicular to the traveling direction of the vehicle. As shown in FIG. 5, the spot shape of the laser beam to be scanned is an elliptical shape that is short in the traveling direction of the vehicle and long in the direction perpendicular to the traveling direction. The laser beam emitted from the laser diode 11 of the vehicle type sensor 1 is reflected on the upper surface of the vehicle traveling on the road. When there is no traveling vehicle, the laser beam emitted from the laser diode 11 is reflected on the road surface. This reflected light is received by the photodiode 22 which is a light receiving element.
[0030]
The output of the photodiode 22 is I / V converted by the I / V conversion circuit 24, and after the noise component is removed by the anti-pass filter (BPF) 25, it is amplified by the amplifier 26 and input to the time difference detection unit 27. Is done. In addition, a signal indicating the light emission timing in the laser diode 11 is input from the LD driver 16 to the time difference detection unit 27. Therefore, the time difference detection unit 27 can detect the time difference T1 between the emission time of the laser beam at the laser diode 11 and the reception time of the reflected light at the photodiode 22.
[0031]
The control unit 10 calculates the distance from the time difference T1 to the reflecting surface (road surface or vehicle traveling on the road) reflecting the laser beam emitted from the laser diode 11 from the following equation.
2 × L1 = C × T1 where C is the speed of light.
[0032]
On the other hand, the distance Lr from the laser vehicle shape sensor 1 to the road surface is known. The laser beam emitted from the laser diode 11 is scanned in the width direction of the vehicle by the polygon mirror 13, and the scanning angle θ 1 of the laser beam by the polygon mirror 13 is detected by the encoder 15. The control unit 10 calculates the height H1 of the reflecting surface that reflects the laser beam emitted from the laser diode 11 from the following equation.
[0033]
H1 = Lr−L1 × cos θ1
Here, the vehicle sensor 1 scans the laser beam emitted from the laser diode 11 in the width direction of the vehicle by the polygon mirror 13, and the vehicle is scanned with respect to the scanning direction of the laser beam emitted from the laser diode 11. Traveling vertically. Therefore, the vehicle shape sensor 1 can measure the upper surface shape of the vehicle from the vehicle head to the vehicle tail.
[0034]
The vehicle height is measured from the vehicle height measured from the vehicle head to the vehicle tail,
Measured value of vehicle height = Lr−H1
Among these, the maximum value is the vehicle height of the vehicle. Further, the vehicle height measurement value measured from the vehicle head to the vehicle tail by the vehicle shape sensor 1 is input to the dimension measurement calculation unit 6.
[0035]
Further, the detection position where the vehicle sensor 1 detects the presence or absence of the vehicle is shifted in the vehicle traveling direction by the length of the laser beam emitted from the laser diode 11 at the maximum in the vehicle traveling direction. Since the laser beam emitted from the laser diode 11 has a shape that is short in the traveling direction of the vehicle (an elliptical shape that is elongated in a direction perpendicular to the traveling direction of the vehicle), the vehicle-shaped sensor 1 is on the road where the presence or absence of the vehicle is detected. Deviation in detection position can be suppressed. Therefore, the detection accuracy of the front and rear ends of the vehicle traveling on the road is improved, and as a result, the measurement accuracy of the vehicle length is improved.
[0036]
Next, the operation of measuring the side shape and the vehicle width of the vehicle traveling on the road by the vehicle shape sensors 2 and 3 attached to both sides of the first gantry 6 will be described with reference to FIG. As shown below, the vehicle shape sensor 2 scans one side (left side) of a vehicle traveling on a road with a laser beam to measure the shape of the left side of the vehicle. The other side surface (right side surface) of the vehicle is scanned with a laser beam to measure the shape of the right side surface of the vehicle. As shown in FIG. 7, the spot shape of the laser beam emitted from the laser diodes 11 of the vehicle shape sensors 2 and 3 is a short shape perpendicular to the traveling direction of the vehicle (an elliptical shape elongated in the traveling direction of the vehicle). is there. Similarly to the vehicle sensor 1, the vehicle sensors 2 and 3 also have the time difference detector 27 to emit the laser beam from the laser diode 11 and the light reception time of the reflected light reflected from the side surface of the vehicle at the photodiode 22. , Time differences T2 and T3 are detected.
[0037]
The control unit 10 of each of the vehicle sensors 2 and 3 determines the distances L2 and L3 from the time differences T2 and T3 to the reflecting surface (the road surface or the vehicle traveling on the road) that reflects the laser beam emitted from the laser diode 11. Is calculated from the following equation.
Vehicle shape sensor 2: 2 × L2 = C × T2
Vehicle shape sensor 3: 2 × L3 = C × T3 where C is the speed of light.
[0038]
On the other hand, the installation interval Lw between the laser vehicle shape sensor 2 and the laser vehicle shape sensor 3 is known. Further, the encoders 15 detect the scanning angles θ2 and θ3 at which the laser beam emitted from the laser diode 11 is scanned by the polygon mirror 13 in the vehicle width direction. Accordingly, the control units 10 of the vehicle sensors 2 and 3 can respectively calculate horizontal distances w2 and w3 to the reflecting surface that reflects the laser beam emitted from the laser diode 11.
[0039]
Vehicle shape sensor 2: w2 = L2 × sin θ2
Vehicle shape sensor 3 : w3 = L3 × sin θ3
Here, the vehicle sensors 2 and 3 scan the laser beam emitted from the laser diode 11 in the width direction of the vehicle by the polygon mirror 13, and the vehicle moves in the scanning direction of the laser beam emitted from the laser diode 11. On the other hand, since the vehicle travels in the vertical direction, the side shape of the vehicle can be measured from the vehicle head to the vehicle tail. The vehicle shape sensor 2 measures the shape of the left side surface of the vehicle from the vehicle head to the vehicle tail, and the vehicle shape sensor 3 measures the shape of the right side surface of the vehicle from the vehicle head to the vehicle tail.
[0040]
As apparent from the above description, the following equation using the measurement result of the vehicle type sensors 2, Ki de is possible to calculate the width of the vehicle over Kuzumo from Headway,
Vehicle width = Lw-(w2 + w3)
The maximum value of the vehicle width obtained here is the measured vehicle width (vehicle width).
[0041]
Furthermore, the operation | movement which the vehicle shape sensor 4 attached to the 2nd gantry 7 measures the front shape of the vehicle which drive | works on a road is demonstrated referring FIG. As described above, the vehicle shape sensor 4 scans the laser beam in the traveling direction of the vehicle. Further, as shown in FIG. 9, the spot shape of the laser beam is an elliptical shape that is short in the traveling direction of the vehicle and long in the vertical direction with respect to the traveling direction. The laser beam emitted from the laser diode 11 of the vehicle shape sensor 4 is reflected on the front surface of the vehicle traveling on the road as shown in FIG. When there is no traveling vehicle, the laser beam emitted from the laser diode 11 is reflected on the road surface. Similarly to the above-described vehicle sensors 1 to 3, the vehicle-type sensor 4 also includes a time difference detection unit 27 that calculates a laser beam emission time at the laser diode 11 and a reception time of reflected light reflected from the front of the vehicle at the photodiode 22. The time difference T4 is detected.
[0042]
The controller 10 calculates a distance L4 from the time difference T4 to the reflecting surface (road surface or vehicle traveling on the road) reflecting the laser beam emitted from the laser diode 11 from the following equation.
2 × L4 = C × T4 where C is the speed of light.
[0043]
Here, since the vehicle shape sensor 4 also scans the laser beam emitted from the laser diode 11 in the traveling direction of the vehicle with the polygon mirror 13, the cross-sectional shape of the front surface of the vehicle can be measured.
[0044]
Further, the vehicle length can be measured by a combination with the vehicle-type sensor 1 attached to the center of the first gantry 6. Specifically, it is measured by the vehicle sensor 4 attached to the second gantry 7 at the timing when the vehicle sensor 1 attached to the center of the first gantry 6 detects the passage of the rear end of the vehicle. It is calculated from the horizontal distance Lc to the front of the vehicle (the horizontal distance between the vehicle shape sensor 4 and the front of the vehicle).
[0045]
The horizontal distance Lc is
Lc = L4 × sin θ4 The horizontal distance Lx between the vehicle sensor 1 attached to the center of the first gantry 6 and the vehicle sensor 4 attached to the center of the second gantry 7 is known. Therefore, the vehicle length can be calculated by vehicle length = Lx−Lc.
[0046]
Here, as described above, the laser beam emitted from the laser diode 11 of the vehicle shape sensor 1 has a shape that is short in the traveling direction of the vehicle (an elliptical shape that is elongated in a direction perpendicular to the traveling direction of the vehicle). Since the shift of the detection position on the road where the presence or absence of the vehicle is detected in 1 is suppressed, the detection accuracy of the rear end of the vehicle traveling on the road is improved. Therefore, the measurement accuracy of the vehicle length measured by the above method is also improved.
[0047]
Thus, in the vehicle detection system of the above embodiment, the spot shape of the laser beam that scans in the direction perpendicular to the passing direction of the vehicle is elongated in the scanning direction, so the amount of reflected light reflected by the vehicle is received. It is possible to improve the position accuracy for detecting the passing object while ensuring the above. Thereby, the length (vehicle length) in the traveling direction of the vehicle can be measured with high accuracy.
[0048]
As the vehicle progresses, the laser beam emitted from the laser diode 11 of the vehicle sensor 4 attached to the second gantry 7 is reflected from the upper surface of the vehicle. Can be measured. Here, if the height of the vehicle measured by the vehicle shape sensor 1 and the height of the vehicle measured by the vehicle shape sensor 4 are greatly different values, it is considered that some measurement error has occurred. By measuring the measurement result at this time as error data, the measurement accuracy can be further improved.
[0049]
In addition, the measurement by laser car shape sensor may be affected by reflection of rain and snow, but the reflection by rain and snow is discontinuous in time and space, so the continuity at the measurement point is calculated. In addition, by removing discontinuous points, the influence of rain and snow can be suppressed, and the measurement accuracy can be further improved.
[0050]
【The invention's effect】
As described above, according to the present invention, it is possible to measure the specifications of a vehicle passing through a road with high accuracy.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a vehicle measurement system according to an embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a laser vehicle type sensor according to an embodiment of the present invention.
FIG. 3 is a diagram illustrating a vehicle width, a vehicle height, and a vehicle length in a vehicle.
FIG. 4 is a diagram for explaining measurement of the shape of the upper surface of the vehicle.
FIG. 5 is a diagram showing the shape of a laser beam used for measuring the upper surface shape of a vehicle.
FIG. 6 is a diagram illustrating measurement of a side shape of a vehicle.
FIG. 7 is a diagram showing the shape of a laser beam used for measuring the side shape of a vehicle.
FIG. 8 is a diagram illustrating measurement of the shape of the front surface of the vehicle.
FIG. 9 is a diagram showing the shape of a laser beam used for measuring the shape of the front surface of the vehicle.
[Explanation of symbols]
1 to 4-laser vehicle type sensor 5-dimension measuring unit 6-first gantry 7-second gantry 10-control unit 11-laser diode 12-projecting lens 13-polygon mirror 15-encoder 21-receiving lens 22-photo Diode 27-time difference detector

Claims (2)

First to third light emitting units that emit laser beams arranged in the width direction of the passageway above the passageway through which the vehicle passes;
A fourth light emitting unit that emits a laser beam attached above the passage that is a predetermined distance away in the vehicle passing direction than the first to third light emitting units;
The first to provided third respectively for each emission of the first to third scanning unit for scanning in the vertical direction emitted laser beam with respect to the passing direction of vehicles,
A fourth scanning unit that scans the laser beam emitted from the fourth light emitting unit in the vehicle passing direction;
Provided with each of the first to fourth scanning units, and first to fourth light receiving units for receiving reflected light of the scanned laser beam, and
The laser beam spot shape that will be emitted from the first light-emitting portion located at the center is an elongated shape in the scanning direction of the laser beam by the first scanning unit,
Elongated in a direction perpendicular to the spot shape of the second, and the laser beam that will be emitted from the third light emitting part, the scanning direction of the laser beam by each of the second and third scan portion located on both sides And
The spot shape of the laser beam emitted from the fourth light emitting unit is a shape elongated in a direction perpendicular to the scanning direction of the laser beam by the fourth scanning unit,
Emitted from the first light emitting portion, and a vehicle detector for detecting the presence or absence of a vehicle passing through the passage from the reflected light of the laser beam received by the first light receiving portion,
The emission time of the laser beam emitted from the second and third light emitting units, the reception time of the reflected light in the second and third light receiving units, and the laser beam in the second and third scanning units A vehicle width calculation unit that measures the side shape of the vehicle passing through the passage using the scanning angle and calculates the width of the vehicle;
Using the emission time of the laser beam emitted from the fourth light emitting unit, the reception time of the reflected light in the fourth light receiving unit, and the scanning angle of the laser beam in the fourth scanning unit, The laser beam emitted from the fourth light emitting unit at the timing when the vehicle detecting unit detects the rear end of the vehicle passing through the passing path while measuring the cross-sectional shape of the front surface of the passing vehicle. A vehicle length calculation unit that calculates a length of a vehicle passing through the passage from a distance to the front surface of the vehicle measured using the vehicle detection device. A vehicle passing through the passage using the emission time of the laser beam emitted from the first light emitting unit, the reception time of the reflected light at the light receiving unit, and the scanning angle of the laser beam at the first scanning unit. The vehicle detection device according to claim 1 , further comprising a vehicle height calculation unit that calculates the height of the vehicle.

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