JPH10293897A - Vehicle shape discrimination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the structure of a vehicle shape discrimination device and to inexpensively discriminate the shape of a vehicle by deciding the height of the vehicle based on the displacement of reflecting position of the detected beam light and sorting the vehicle based on its sectional outline set in its height direction. SOLUTION: An illumination part 4 is attached to the arm of a support 3 and emits a fine beam light onto the road surface with an LED, etc., used as its light source. A BPF 6 that is corresponding to the wavelength of irradiated light is attached to the front face of a camera 5, and the camera 5 detects the reflection of the light of the part 4 as the image information. A video interface part 71 of a vehicle shape discrimination device 7 outputs the commands to the part 4 and the camera 5 and inputs the images received from the camera 5. An image processing part 72 detects the position of reflected light based on the image signals inputted via the part 71. A vehicle height calculation part 73 calculates the height of a vehicle from the position of reflected light detected at the part 72. Then a vehicle shape discrimination part 74 decides the shape of the vehicle based on the height of each part of the vehicle, i.e., the sectional shape of the vehicle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring the shape of a vehicle by using an image processing technique and determining the shape of the vehicle.

[0002]

2. Description of the Related Art FIG. 13 is a conceptual diagram showing an example of a conventionally used apparatus for recognizing the shape of a vehicle. In FIG. 13, 1 is a road, 2 is a vehicle running on the road, and 3 is a column installed on the road. Reference numeral 14 denotes a laser light emitter / receiver installed on the arm of the column 3, and reference numeral 15 denotes a determination unit that measures a cross-sectional shape of the vehicle 2 from a signal from the laser light emitter / receiver 14.

FIG. 14 is a diagram showing the internal structure of a laser projector. In FIG. 14, reference numeral 16 denotes a distance measuring unit that measures a distance from the light emitting and receiving unit 14 to the vehicle 2 by detecting a difference between light emission and light reception, and 17 emits a laser based on a command from the distance measuring unit 16. Floodlight unit, 18 is vehicle 2 or road 1
This is a light receiving unit that receives the reflected light of the laser from the camera. One more
Reference numeral 9 denotes a polygon mirror that scans the laser beam output from the light projecting unit 17 in the width direction of the road 1 and receives reflected light to enter the light receiving unit 18.

FIG. 15 is an explanatory view showing the irradiation direction of the laser beam. As shown in FIG. 15, the laser beam output from the laser projector 14 is reflected on the surface of the road 1 or on the vehicle 2 to project the laser beam. Return to the light receiver 14. Conventional vehicle shape discriminator
As described above, the laser is constantly scanned on one section in the width direction of the road 1 using the polygon mirror 19 to measure the distance to the reflecting object at each position, and when the vehicle 2 passes through the inside, the distance is measured. The shape of the vehicle 2 is obtained by measuring the difference in distance to the target.

[0005]

Since the conventional vehicle shape discriminating apparatus scans using the polygon mirror 19, it is necessary to rotate the polygon mirror 19 with a predetermined accuracy. However, such moving parts are the MT of the system.
This was a major factor in lowering BF. Further, there is a problem that the apparatus becomes complicated in terms of a hermetic structure for protecting the laser projector / receiver 14 and the polygon mirror 19 from a bad environment on the road 1 and cooling. In addition, the cost of the laser element is high, and in the case of continuous operation for 24 hours such as monitoring, the frequency of replacing the laser element increases, and the maintenance cost is higher than other light sources. .

[0006] In order to solve such a problem, a vehicle shape discriminating apparatus according to the present invention can discriminate a vehicle shape by a simple method.

[0007]

According to a first aspect of the present invention, there is provided a vehicle shape discriminating apparatus for irradiating a road surface with a light beam;
An imaging unit that receives the light beam, a vehicle height calculation unit that determines a vehicle height from a displacement of a reflection position of the light beam detected by the imaging unit, and a height direction from a road surface at each part of the vehicle. And a vehicle determination unit for classifying the vehicle into one of several preset vehicle profiles based on the cross-sectional contour (profile) of the vehicle.

The vehicle type discriminating apparatus according to a second aspect of the present invention includes a speed sensor for measuring the speed of the vehicle and a vehicle length calculator for measuring the length of the vehicle from the speed information.

[0009] The vehicle shape discriminating apparatus according to the third invention comprises:
In order to reduce the influence of halation, a plurality of imaging units are provided.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. 1 and 2 are an external view and a configuration diagram, respectively, showing a first embodiment of the present invention. In the drawings, 1 to 3 have functions similar to those of the conventional example shown in FIG. Reference numeral 2 denotes a vehicle running on a road, and reference numeral 3 denotes a support installed on the road. Reference numeral 4 denotes an illumination unit which is attached to the arm of the column 3 and emits a thin beam of light to the road surface using an LED or the like as a light source. Reference numeral 5 denotes an illumination unit which is attached to the arm of the column 3 and reflects light emitted from the illumination unit 4. A camera 7 for detecting as image information receives a video signal from the camera 5, calculates the height of the vehicle 2 from the position of the reflected light,
This is a vehicle shape discriminating device that discriminates the vehicle shape from the value. Also,
As shown in FIG. 2, a band-pass filter 6 corresponding to the wavelength of the illumination light is attached to the front of the camera 5, and the vehicle shape discriminating device 7 outputs a command to the illumination unit 4 and the camera 5. A video interface unit 71 for inputting an image from the camera 5; an image processing unit 72 for detecting the position of reflected light from the image signal input to the video interface unit 71; The vehicle height calculation unit 73 calculates the vehicle height from the position of the light, and the vehicle shape determination unit 74 determines the vehicle shape from the vehicle height of each part, that is, the cross-sectional shape of the vehicle.

The operation of the vehicle type discriminating apparatus shown in the first embodiment will be described below. First, the illumination unit 4 emits a beam of light to the road 1. The camera 5 is set so that its optical axis forms an angle with the optical axis of the illumination unit 4 and the scanning direction is the road 1.
And the position where the beam hits the surface of the road 1 or the vehicle 2 is captured as an image. FIG. 3A is a diagram illustrating a light path when the vehicle 2 is not on the road 1, that is, when light emitted from the illumination unit 4 is reflected on the surface of the road 1 and enters the camera 5. ,
FIG. 3B is a diagram illustrating a light path when the vehicle 2 is on the road 1. FIG. 4 shows an example of a multi-value image on a display of an image taken by the camera 5,
FIG. 4A shows the case where there is no vehicle, and FIG. 4B shows the case where there is a vehicle. In this way, the reflected light from the illumination 4
Is shifted right and left on the screen depending on the presence or absence of the vehicle 2 and the height of the vehicle 2. For example, under the installation condition as shown in FIG. 3, as the vehicle height is higher, the vehicle is displaced rightward in the figure as shown in FIG. In the device according to the present invention, the height of the vehicle 2 is measured from the deviation.

Next, the flow of signals and data will be described. As shown in FIG. 2, first, the video interface unit 71 internally generates an imaging timing signal,
And a light emission command 9 synchronized with the imaging timing is output to the illumination unit 4. Further, an image signal 10 captured based on the imaging timing signal 8 is input.

The image processing section 72 detects the position of the reflection from the image input to the video interface section 71 by a predetermined image processing technique. FIG. 5 shows an example of the image processing method. In FIG. 5, the fact that the magnitude of the reflection of the light beam to be detected in the image is known in advance and that the region where the position of the light beam should exist is limited is used. Finding a point of a predetermined luminance or more from the valued image,
Detect the light beam. FIG. 5A shows a multi-value image of the input image on the display. As shown in FIG. 6, if the reflection position on the screen is known, the actual height of the vehicle 2 can be obtained geometrically. The vehicle height calculation unit 73 obtains the relationship between the spot position of the reflected light in the image and the actual vehicle height in advance, and calculates the vehicle height using a preset conversion table.

If the above processing is performed at a cycle sufficiently faster than the speed of the vehicle 2, the height of the ground at a plurality of points in the longitudinal direction of one vehicle 2 is obtained. 7, a cross-sectional shape in the height direction of the vehicle 2 is obtained. In FIG. 7, the horizontal axis represents time, and the vertical axis represents the position of reflected light at each position, that is, the vehicle height.
Based on this cross-sectional shape, the shapes of large one-box vehicles (such as buses), small sedans, and small one-boxes are classified. For example, as illustrated in FIG. 8A, when the distribution in the height direction is divided into two or more portions such as a hood portion and a driver's cab, the sedan system is used. One box. Further, even in the same one box, a bus having a height equal to or more than a certain value is determined to be a large bus by determining the height. In the first embodiment, an example in which an area sensor is used as the camera 5 has been described. However, if a line sensor is used, the interval between image inputs is further reduced, and the vehicle 2
The resolution in the traveling direction with respect to is improved.

Embodiment 2 9 and 10 are an external view and a configuration diagram showing a second embodiment of the present invention, in which 1 to 7 have the same functions as those of the embodiment shown in FIG. A speed sensor 11 measures the speed of the vehicle using the Doppler effect of a microwave or the like.

The operation of the vehicle type discriminating apparatus according to the second embodiment will be described below. In FIG. 10, a lighting unit 4, a camera 5, a video interface unit 71 to a vehicle height calculation unit 7
The operations up to 3 are the same as in FIG. The speed sensor 11
It is installed slightly upstream of the camera 5 and detects the approach of the vehicle 2 and measures the speed V of the vehicle 2. On the other hand, the vehicle height calculation unit 73 always measures the height of the passing vehicle 2 and obtains the profile of the vehicle 2 by measuring the height of each part of the vehicle 2 every time the camera 5 captures an image as shown in FIG. . By setting the time when the vehicle 2 rises from the road 1 to the vehicle 2 in this profile to time S and the time when the vehicle 2 falls to the road 1 to time E, the transit time from the front end to the rear end of the vehicle 2 is measured. The vehicle length calculator 75 calculates the vehicle length by the following calculation. Front-to-rear end transit time T = E−S Vehicle length L = T × V The vehicle shape determination unit 74 performs the determination with reference to the vehicle length to perform the determination with higher determination accuracy.

Embodiment 3 FIGS. 11 and 12 are an external view and a configuration diagram, respectively, showing a third embodiment of the present invention. In the drawings, 1 to 7 have functions similar to those of the first embodiment shown in FIG. Reference numeral 12 denotes an auxiliary camera having the same function as the camera 5,
It is installed at another angle. Reference numeral 13 denotes a bandpass filter having the same function as the bandpass filter 6 provided on the front of the camera 5.

The operation of the vehicle type discriminating apparatus according to the third embodiment will be described below. The vehicle shape discrimination device according to the present invention measures the vehicle height based on the position of the reflected light from the illumination unit 4, but cannot measure when the vehicle is subjected to halation by sunlight or the like. Therefore, the auxiliary camera 12 is installed at an angle different from that of the original camera 5, and even if the camera 5 is in a position where it is easily affected by disturbance light, the reflected light is not affected by disturbance when viewed from another direction. It is to detect. As for the signal flow, as shown in FIG. 12, the video interface unit 71 similarly outputs the imaging trigger signals 8 and 8 ′ to the camera 5 and the auxiliary camera 12, and similarly outputs the video signals 10 and 10 ′. Is entered. The vehicle shape discriminating unit 7 performs similar processing on both video signals in parallel. The vehicle height determination unit 73 normally uses the measurement result based on the video signal 8, but when the spot light cannot be detected due to the influence of disturbance light such as sunlight, the result based on 8 ′ is used. Thus, even if the camera 5 cannot correctly detect the reflection position of the illumination light due to halation of disturbance light, the possibility that the camera 5 can detect the reflection position with the other auxiliary camera 12 increases.

[0019]

According to the first aspect of the invention, the profile of the longitudinal section of the vehicle can be obtained with the configuration of one lighting unit and the imaging unit such as a camera, so that the apparatus is simplified and the vehicle shape is reduced. Can be determined.

According to the second aspect of the present invention, the speed of the vehicle is measured by the speed sensor, and not only the information on the shape of the vehicle but also the actual vehicle length can be calculated.

According to the third aspect, by using a plurality of imaging units, even if any one of the imaging units becomes unmeasurable due to halation of sunlight or the like, another imaging unit having a different installation angle is used. , It is possible to suppress the influence of performance degradation due to the environment.

[Brief description of the drawings]

FIG. 1 is a first embodiment of a vehicle shape discriminating apparatus according to the present invention;
It is a key map showing appearance of.

FIG. 2 is a first embodiment of a vehicle shape discriminating apparatus according to the present invention;
FIG. 3 is a diagram showing the configuration of FIG.

FIG. 3 is a first embodiment of a vehicle shape discriminating apparatus according to the present invention;
It is a figure explaining operation of.

FIG. 4 is a first embodiment of a vehicle shape discriminating apparatus according to the present invention;
It is a figure explaining operation of.

FIG. 5 is a first embodiment of a vehicle shape discriminating apparatus according to the present invention;
It is a figure explaining operation of.

FIG. 6 is a first embodiment of a vehicle shape discriminating apparatus according to the present invention;
It is a figure explaining operation of.

FIG. 7 is a first embodiment of a vehicle shape discriminating apparatus according to the present invention;
It is a figure explaining operation of.

FIG. 8 is a first embodiment of a vehicle shape discriminating apparatus according to the present invention;
It is a figure explaining operation of.

FIG. 9 is a second embodiment of the vehicle shape discriminating apparatus according to the present invention;
It is a key map showing appearance of.

FIG. 10 is a diagram showing a configuration of a second embodiment of a vehicle shape discriminating apparatus according to the present invention.

FIG. 11 is a conceptual diagram showing an appearance of a vehicle shape discriminating apparatus according to a third embodiment of the present invention.

FIG. 12 is a diagram showing a configuration of a third embodiment of the vehicle shape discrimination device according to the present invention.

FIG. 13 is a conceptual diagram showing the actual appearance of a conventional vehicle type discriminating apparatus.

FIG. 14 is a diagram for explaining the operation of a conventional vehicle shape discriminating apparatus.

FIG. 15 is a view for explaining the operation of a conventional vehicle shape discriminating apparatus.

[Explanation of symbols]

1 Road, 2 target vehicles, 3 pillars, 4 lighting section, 5
Camera, 6 bandpass filter, 7 vehicle shape discriminator,
8 imaging trigger signal, 8 ′ imaging trigger signal, 9 flash command, 10 video signal, 10 ′ video signal, 11
Speed sensor, 12 auxiliary camera, 13 bandpass filter, 14 laser emitter / receiver, 15 discriminator, 16 distance measuring unit, 17 light emitting unit, 18 light receiving unit, 19 polygon mirror, 71 video interface unit, 72 image processing unit, 73 Vehicle height calculation unit, 74 vehicle type discrimination unit, 75 vehicle length calculation unit.

Claims (3)

[Claims] An illumination device installed on a road for irradiating a light beam with a narrow beam on a road surface, and an angle with an optical axis of the illumination device for capturing an image of an area irradiated with the light beam. An image pickup unit installed with: an image processing unit that detects a reflection position of illumination light from an image each time an image is picked up by the image pickup unit; and a reflection position when passing through a vehicle obtained as a result of image processing by the image processing unit. And a vehicle height calculator for sequentially calculating the height of the vehicle from the amount of deviation from the reflection position when there is no vehicle and the geometrical conditions of light incidence and reflection, and outputting a contour (profile) in the height direction of the vehicle. A vehicle shape discriminating unit for judging to which of a predetermined vehicle type the vehicle belongs based on the vehicle height calculation result of the vehicle height calculating unit. 2. The vehicle shape discriminating apparatus according to claim 1,
A speed sensor unit that measures the speed of the vehicle and a time required to pass from the front end to the rear end of the vehicle are obtained by using a vehicle profile obtained by the vehicle height calculation unit, and the speed information from the speed sensor unit is used. And a vehicle length calculating unit for calculating the length of the vehicle. 3. The vehicle shape discriminating apparatus according to claim 1,
A vehicle shape discriminating apparatus, wherein a plurality of the image pickup units are installed at different angles.