JP3822154B2 - Vehicle detection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle detection device that detects surrounding vehicles using laser light.
[0002]
[Prior art]
Conventionally, at an intersection with poor visibility, a curve mirror or the like has been installed so that the direction of the blind spot area can be seen in order to prevent a collision accident between vehicles.
In addition, in order to make the other vehicle recognize the presence of the host vehicle in the blind spot area, or to recognize the other vehicle in the blind spot area on the host vehicle side, irradiate the laser beam to the irradiation distance according to the vehicle speed, There is a device that displays the position of a vehicle in the surroundings by the laser light (see Patent Document 1).
[0003]
[Patent Document 1]
Japanese Utility Model Publication No. 06-65089
[Problems to be solved by the invention]
However, when a curved mirror is installed as in the conventional case, the other vehicle that is projected appears to be small because the area of the mirror is not sufficient, or the other vehicle that is projected appears to be distorted due to the curved shape of the mirror. Therefore, there is a problem that it is difficult to confirm the existence of other vehicles, particularly from a distance.
Further, when laser light is irradiated and the position of the vehicle is displayed around by the laser light, it is assumed in the prior art that the laser light itself (the path of the laser light in the air) is visible with the naked eye. However, it is difficult to see the laser beam with the naked eye unless there are many reflectors such as raindrops, fog, dust, and smoke particles in the air. It is difficult to recognize a vehicle existing in the vehicle or to recognize another vehicle in the blind spot area on the own vehicle side. On the other hand, in a situation where there are many laser beam reflectors in the air, the reachable distance of the laser beam itself becomes short, so that there is a problem that a sufficient warning cannot be given to other vehicles.
Furthermore, when there are a plurality of vehicles in the blind spot area, the number of laser beams is also plural, so there is a problem that the moving direction and moving speed of the target object can be accurately recognized or difficult to recognize. .
[0005]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle detection device that can detect a vehicle existing in a blind spot area together with its moving direction and moving speed.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, a vehicle detection device according to the invention of claim 1 is mounted on a vehicle and emits laser light in the traveling direction of the vehicle (for example, the laser of the embodiment). The light projector 2), the laser light recognition means (for example, the infrared camera 3 of the embodiment) capable of recognizing the laser light reflected on the road surface, and whether or not the recognized laser light is from a vehicle other than the own vehicle. If it is determined that the recognized laser beam is a laser beam irradiated by the other vehicle, the laser beam determining unit (for example, the laser beam determining unit 11 of the embodiment) It is provided with a traveling state detecting means (for example, the traveling state detecting means 12 in the embodiment) for detecting the traveling state of the other vehicle based on at least one of a movement locus, a shape, and a lighting state.
[0007]
The vehicle detection apparatus having the above configuration irradiates laser beams indicating the presence of the own vehicle toward the road surface by the laser beam projecting unit and also reflects the laser beam reflected on the road surface by the laser beam recognition unit. When recognized, it is determined whether or not the recognized laser beam is from a vehicle other than the own vehicle, and the recognized laser beam is determined to be a laser beam emitted from another vehicle other than the own vehicle. In this case, the traveling state detection means detects the traveling state of the other vehicle based on at least one of the recognized movement locus, shape, and lighting state of the laser beam, and notifies the driver of this, The host vehicle can be driven in response to the running state of the other vehicle.
[0008]
According to a second aspect of the present invention, there is provided the vehicle detection device according to the first aspect, wherein the traveling state detection means is configured to move the moving direction or the moving speed of the other vehicle based on the recognized movement path of the laser beam. Is detected.
The vehicle detection device having the above configuration notifies the driver of this by accurately detecting the moving direction or moving speed of the other vehicle based on the recognized moving locus of the laser beam, and the driving of the other vehicle. The host vehicle can be driven in response to the situation.
[0009]
A vehicle detection apparatus according to a third aspect of the present invention is the vehicle detection apparatus according to the first or second aspect, wherein the blinking interval changing means is capable of changing the blinking interval of the laser light in accordance with the traveling speed of the vehicle. (For example, the blinking interval changing unit 13 of the embodiment), and the traveling state detecting unit detects the traveling speed of the other vehicle based on the recognized blinking interval of the laser beam.
The vehicle detection apparatus having the above configuration notifies the driver of this by accurately detecting the moving speed of the other vehicle from the blinking speed of the laser light without calculating the moving distance of the laser light. The host vehicle can be driven in response to the running state of the other vehicle.
[0010]
A vehicle detection device according to a fourth aspect of the present invention is the vehicle detection device according to any one of the first to third aspects, wherein the laser beam is an infrared laser beam.
The vehicle detection apparatus having the above-described configuration allows the vehicles to confirm the presence of each other with an infrared laser beam that is invisible to the driver's eyes, so that the actual driver's field of view is not affected. The presence can be notified to the driver, and the driver can be driven to deal with the traveling state of the other vehicle.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of a vehicle detection device according to an embodiment of the present invention.
In FIG. 1, reference numeral 1 denotes an on-vehicle ECU (Electronic Control Unit) having a CPU (Central Processing Unit) for controlling the vehicle detection device of the present embodiment, which is mounted on the vehicle detection device of the present embodiment. A laser beam projector 2 for irradiating infrared laser light in the traveling direction of the vehicle and an infrared camera 3 capable of recognizing infrared laser light reflected on the road surface are connected, and vehicle speed information of the vehicle is acquired. A vehicle speed sensor 4 is connected.
[0012]
Thereby, the ECU 1 indicates the existence of the own vehicle to other vehicles by irradiating the infrared laser beam toward the road surface using the laser light projector 2 and other than the own vehicle reflected by the infrared camera 3 on the road surface. When the infrared laser beam is recognized, the traveling state of the other vehicle is detected based on at least one of the movement locus, shape, and lighting state of the recognized infrared laser beam. And the information which shows the driving state of this other vehicle can be given to the driver | operator of the own vehicle, and the driver | operator's attention with respect to a driving | operation can be called.
[0013]
Further, the ECU 1 displays alarm means 5 including a speaker and an alarm lamp for issuing an alarm by voice, light, etc., and an image photographed by the infrared camera 3, and informs the driver of the own vehicle of the presence of other vehicles. For example, a meter-integrated display integrated with a meter that expresses the running state of the host vehicle in numerical form, a NAVID display installed on the console of the host vehicle, and a driver's front view of the front window (front window shield) A monitor 6 including a HUD (Head Up Display) or the like for displaying information at a position not hindering is connected.
[0014]
The ECU 1 also includes an A / D conversion circuit that converts an input analog signal into a digital signal, an image memory that stores a digitized image signal, a CPU (central processing unit) that performs various arithmetic processes, and data that the CPU is in the middle of calculating. RAM (Random Access Memory) used for storage, ROM (Read Only Memory) for storing programs and tables executed by the CPU, maps, etc., drive signal for alarm means 5, output signal for display of monitor 6, etc. A circuit is provided, and an image captured by the infrared camera 3 and an output signal of the vehicle sensor 4 are converted into a digital signal and input to the CPU.
[0015]
In addition, the ECU 1 includes a laser light determination unit 11, a traveling state detection unit 12, and a blinking interval change unit 13.
Here, the laser light determination means 11 reflects the infrared laser light reflected by the road surface and recognized by the infrared camera 3, or the infrared laser light emitted from the laser light projector 2 of the own vehicle or the laser light of another vehicle. It is determined whether the infrared laser light is emitted by the projector 2. The determination method is based on the shape of the road surface reflected spot light of the infrared laser beam or the relationship between the imaging area on the screen and the irradiation position of the infrared laser beam of the host vehicle. The specific determination method will be described later in detail.
[0016]
Further, the traveling state detection unit 12 recognizes the infrared laser beam recognized when the laser beam determination unit 11 determines that the infrared laser beam recognized by the infrared camera 3 is an infrared laser beam emitted from another vehicle. The traveling state of the other vehicle is detected based on at least one of the movement trajectory, shape, and lighting state. The specific method for detecting the traveling state will be described later in detail.
Further, the blinking interval changing means 13 changes the blinking interval of the infrared laser light emitted by the laser light projector 2 according to the traveling speed of the vehicle acquired by the vehicle speed sensor 4.
[0017]
Next, attachment positions of a laser beam projector, an infrared camera, a display, and the like used in the vehicle detection device of the present embodiment will be described with reference to the drawings.
FIG. 2 is a diagram showing attachment positions of a laser beam projector, an infrared camera, a display, and the like in the vehicle.
As shown in FIG. 2, the laser light projector 2 is disposed at a position substantially symmetrical with respect to the vehicle width direction of the host vehicle 10 on the front grill of the host vehicle 10, and the infrared light irradiated from the laser beam projector 2. The laser light spreads in a conical shape that spreads toward the far end. When the infrared laser light is projected onto the road surface (road horizontal surface), the shape of the road surface reflected spot light 31 becomes an elliptical shape. In addition, the infrared laser light is applied to a position at a distance P of about 30 [m] from the host vehicle, for example.
[0018]
Next, the operation of the present embodiment will be described with reference to the drawings.
FIG. 3 is a schematic diagram illustrating an approaching other vehicle detection example in an intersection blind spot area using the vehicle detection device of the present embodiment. FIG. 4 is a schematic diagram illustrating a situation in which another vehicle approaches at the intersection, and FIG. 5 is a schematic diagram illustrating a distance traveled by the other vehicle at the intersection.
In FIG. 3, a frame 14 is a frame indicating the imaging range of the infrared camera 3, and when the host vehicle 10 reaches an intersection 20 with poor visibility due to a building 15 or the like, for example, the other vehicle 30 moves from the left lateral direction. When approaching the intersection 20, first, the tip of the road surface reflected spot light 31 of the infrared laser light of the other vehicle 30 appears from behind the object.
[0019]
Although the road surface reflected spot light 31 of the infrared laser light cannot be seen with the naked eye, other vehicles entering the intersection 20 by capturing the road surface reflected spot light 31 through the infrared camera 3 mounted on the host vehicle 10. 30 approaches can be detected.
Then, the surrounding image of the host vehicle 10 captured by the infrared camera 3 and the captured road surface reflected spot light 31 of the infrared laser light are displayed on a front window (front window shield) or the like using a monitor device such as HUD7. Thus, the driver can grasp the approach information of the other vehicle 30 without looking at the other vehicle 30 itself existing in the blind spot area.
[0020]
That is, regarding the position of the road surface reflected spot light 31 of the infrared laser light photographed by the infrared camera 3, when comparing the frames of the images photographed by the infrared camera 3 in time series, first, as shown in FIG. In the frame at time “tn”, the tip of the road surface reflected spot light 31 of the infrared laser light irradiated by the other vehicle 30 existing in the blind spot region appears from the shadow.
Further, as shown in FIG. 4B, in the frame at the next time “tn + 1”, about half of the road surface reflected spot light 31 of the infrared laser light emitted by the other vehicle 30 existing in the blind spot area is It can be recognized on the road surface.
Further, as shown in FIG. 4C, in the next frame “tn + 2”, all of the road surface reflected spot light 31 of the infrared laser light irradiated by the other vehicle 30 existing in the blind spot area is converted to the road surface of the intersection 20. While being able to recognize above, the front-end | tip of the other vehicle 30 appears from a shadow.
[0021]
In this way, the road surface reflected spot light 31 is projected so as to appear slightly shifted in the traveling direction as the other vehicle 30 approaches the intersection 20. Therefore, the traveling state detection means 12 included in the ECU 1 calculates the moving speed of the other vehicle 30 from the moving distance L of the road surface reflected spot light 31 shown in FIG. 5 and the frame rate of the infrared camera 3 according to the following equation (1). V is obtained.
Movement speed V = movement distance L / [(1 / frame rate) × number of frames] (1)
Further, the traveling state detection means 12 displays the approaching speed (= moving speed V) of the other vehicle 30 to the intersection 20 thus obtained in real time in the HUD 7, so that the driver of the own vehicle 10 can It is possible to determine whether or not the other vehicle 30 is decelerating from the approach speed V of 30 and the amount of change thereof, and it is possible to enter the intersection 20 and pass through the intersection 20 more safely.
[0022]
The movement distance of the road surface reflected spot light 31 can be easily calculated by comparing a reference distance obtained in advance from a distance from the lower end on the screen and the actual movement amount of the pixel. Further, the moving distance of the road surface reflected spot light 31 may be measured by other measuring means such as stereo vision.
Further, the road surface reflected spot light 31 emitted from the host vehicle 10 and the road surface reflected spot light 31 emitted from the other vehicle 30 are discriminated by the laser light determination means 11 included in the ECU 1 reflecting the road surface of infrared laser light. The determination is made based on the shape of the spot light 31 or the relationship between the imaging region on the screen and the irradiation position of the infrared laser light of the host vehicle 10.
[0023]
Specifically, when the determination is made based on the shape of the road surface reflected spot light 31, the road surface reflected spot light 31 by the infrared laser light irradiated by the host vehicle 10 looks like a vertically long elliptical shape when viewed from the host vehicle 10. The road surface reflected spot light 31 by the infrared laser light emitted from the other vehicle 30 can be determined from the fact that it looks like a horizontally long oval when viewed from the host vehicle 10.
On the other hand, when determining based on the relationship between the imaging area on the screen and the irradiation position of the infrared laser beam of the host vehicle 10, the irradiation position of the infrared laser beam of the host vehicle 10 is determined in advance, so The appearing road surface reflected spot light 31 is assumed to be from the host vehicle 10, and the other can be determined as the road surface reflected spot light 31 by the infrared laser light irradiated by the other vehicle 30.
[0024]
Further, the ECU 1 may change the blinking interval of the infrared laser light emitted by the laser light projector 2 according to the traveling speed of the vehicle acquired by the vehicle speed sensor 4 by the blinking interval changing unit 13. In this case, the speed of the opponent vehicle can be recognized based on the blinking interval of the infrared laser light recognized by the vehicle infrared camera 3 and the running state detection means 12.
In addition, the road surface reflected spot light 31 of the infrared laser beam and the speed display may be displayed using a display device (for example, a meter-integrated display or NAVI Display) other than the HUD 7 which is one of the monitors 6. An alarm may be issued to the driver of the host vehicle 10 by using means such as sound from a speaker included or light by lighting an alarm lamp.
[0025]
Furthermore, the traveling direction of the vehicle can be specified by making the shape of the road surface reflected spot light 31 of the infrared laser light asymmetrical before and after the traveling direction. In this case, since the traveling direction of the vehicle can be specified by the shape of the road surface reflected spot light 31, it is possible to grasp the traveling direction of the vehicle even when the vehicle is stopped. Specifically, for example, as shown in FIGS. 6A and 6B, the traveling direction of the vehicle can be identified at a glance by directing the tip of the arrow or the tip of the triangle toward the traveling direction of the vehicle. Can do.
[0026]
The shape of the infrared laser beam is not limited to a conical shape, and may be any shape as long as the shape can be easily grasped by the infrared camera 3, such as a fan shape or a cylindrical shape.
Further, the wavelength of the laser light emitted by the laser light projector 2 is not limited to the infrared laser light as long as it can be captured by the camera, and may be laser light such as visible light. For the recognition, it is assumed that a camera capable of recognizing laser light such as visible light is used instead of the infrared camera 3.
[0027]
As described above, in the vehicle detection device of the present embodiment, for example, the own vehicle 10 and the other vehicle 30 or the like use the laser light projector 2 to direct laser light indicating the presence of the own vehicle 10 toward the road surface. When irradiating and recognizing the laser light reflected on the road surface by the infrared camera 3 and determining that the laser light recognized by the laser light determination means 11 is laser light irradiated by a vehicle other than the own vehicle The driving state detecting means 12 detects the driving state such as the moving direction and the moving speed of the other vehicle based on at least one of the recognized movement locus, shape, and lighting state of the laser beam, thereby driving the vehicle. This can be notified to the person, and the host vehicle can be driven in response to the running state of the other vehicle.
[0028]
As a result, for example, in the vicinity of the intersection 20 where visibility is poor due to the shadow of the building 15, the presence information of the other vehicle 30 approaching from the lateral direction of the traveling direction of the host vehicle 10 and the traveling speed thereof can be grasped in advance. Therefore, it is possible to prevent an encounter accident at the intersection 20 with poor visibility.
In addition, when overtaking a forward stop vehicle or the like, a collision with another vehicle coming from the left side or a frontal collision with an oncoming vehicle can be prevented.
[0029]
Furthermore, when infrared laser light is used as the laser light, it becomes possible for the vehicles to recognize other surrounding vehicles regardless of day and night, and the road surface reflected spot light 31 is not visible, so the driver of the oncoming vehicle As long as the user sees the outside world through the front window (front window shield), the driver's field of view of the host vehicle is not disturbed at all.
[0030]
【The invention's effect】
As described above, according to the vehicle detection device of the first and second aspects, the vehicles irradiate the laser beam indicating the existence of the own vehicle toward the road surface, and the irradiation of the other vehicle reflected by the road surface. By detecting a traveling state such as a moving direction and a moving speed of the other vehicle based on at least one of the movement locus, shape, and lighting state of the recognized laser beam, This can be notified to the driver, and the host vehicle can be driven in response to the running state of the other vehicle.
Therefore, the existence of other vehicles existing in the blind spot area in the own vehicle can be recognized early together with the running state, or the other vehicle can be recognized early together with the running state. The effect that it is possible to avoid the collision or the like is obtained.
[0031]
According to the vehicle detection device of the third aspect, even if the moving distance of the laser beam is not calculated, the moving speed of the other vehicle is accurately detected from the blinking speed of the laser beam, and this is notified to the driver. The host vehicle can be driven in response to the running state of the other vehicle.
Therefore, the circuit configuration can be simplified and the scale of the apparatus can be reduced by deleting the memory for storing a plurality of frames of images necessary for calculating the moving distance of the laser beam from the vehicle detection apparatus. It is done.
[0032]
According to the vehicle detection device of the fourth aspect, by using the infrared laser light that is invisible to the driver's eyes, the presence of other vehicles is notified to the driver without affecting the actual driver's field of view. In addition, the driver can drive the host vehicle in response to the traveling state of the other vehicle.
Therefore, it becomes possible for vehicles to recognize other surrounding vehicles regardless of day and night, and since infrared laser light is invisible, it does not give unnecessary dazzling to the driver of the oncoming vehicle, As long as the outside world is seen through the front window (front window shield), there is an effect that the driver's field of view of the host vehicle is not obstructed at all.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a vehicle detection apparatus according to an embodiment of the present invention.
FIG. 2 is a diagram showing attachment positions of a laser beam projector, an infrared camera, a display, and the like in a vehicle.
FIG. 3 is a schematic view showing an approaching other vehicle detection example in an intersection blind spot area using the vehicle detection device of the embodiment.
FIG. 4 is a schematic diagram showing how another vehicle approaches at an intersection.
FIG. 5 is a schematic diagram showing a distance traveled by another vehicle at an intersection.
FIG. 6 is a diagram showing the shape of the road surface reflected spot light of the asymmetric infrared laser light before and after the vehicle traveling direction.
[Explanation of symbols]
1 ECU
2 Laser light projector 3 Infrared camera (laser light recognition means)
4 Vehicle speed sensor 5 Alarm means 6 Monitor 7 HUD
DESCRIPTION OF SYMBOLS 10 Own vehicle 11 Laser light determination means 12 Running state detection means 13 Flashing interval change means 20 Intersection 30 Other vehicle

Claims (4)

A laser beam projecting unit that is mounted on a vehicle and irradiates a laser beam in a traveling direction of the vehicle;
Laser light recognition means capable of recognizing laser light reflected on the road surface;
Laser light determination means for determining whether the recognized laser light is from a vehicle other than the own vehicle;
When it is determined that the recognized laser beam is a laser beam emitted from the other vehicle, the other vehicle travels based on at least one of the movement path, shape, and lighting state of the recognized laser beam. A vehicle detection device comprising: a traveling state detection means for detecting a state. 2. The vehicle detection apparatus according to claim 1, wherein the running state detection unit detects a movement direction or a movement speed of the other vehicle based on the recognized movement locus of the laser beam. A blinking interval changing means capable of changing the blinking interval of the laser light according to the traveling speed of the vehicle;
The vehicle detection apparatus according to claim 1, wherein the traveling state detection unit detects a traveling speed of the other vehicle based on the recognized blinking interval of the laser beam. The vehicle detection device according to any one of claims 1 to 3, wherein the laser beam is an infrared laser beam.

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