JP2004252550A - Driving support device - Google Patents

Abstract

An object of the present invention is to provide a driving support device capable of appropriately judging a situation around a host vehicle, detecting a danger scene, and notifying a driver.
In a captured image in front of a vehicle, a road edge and a vertical line segment are detected, and a crossing point between the two is detected to identify a dangerous scene. The dangerous scene detected by this means has a high degree of accuracy that accurately reflects the situation around the host vehicle. By notifying the driver of the dangerous scene by limiting the moving speed of the dangerous scene to the road surface to be equal to or less than the predetermined value, it is possible to further reduce the erroneous recognition of the dangerous scene and to realize a driving support device that does not bother the driver.
[Selection] Fig. 2

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a technique for preventing an accident in a driving assistance system for a vehicle by detecting a dangerous scene and notifying the driver of the situation.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there has been proposed a driver support system that warns a driver that a vehicle is traveling in an area where there is a high risk of encountering jumping of a pedestrian, a bicycle, or the like using a navigation system. Reference 1).
[0003]
[Patent Document 1]
JP-A-2002-213970 (Claims)
[0004]
[Problems to be solved by the invention]
However, in the driver assistance system described in Patent Literature 1, since the danger is determined based on the navigation system, the situation around the vehicle cannot be properly determined, and it is difficult to provide accurate information. In addition, since the judgment of danger is affected by the presence of other vehicles and poor visibility, it is often not possible to detect a danger scene only with data mounted on the navigation system.
[0005]
In view of these problems, the present invention has an object to provide a driving assistance device that can appropriately detect a danger scene that cannot be detected by a navigation system, such as another vehicle or an intersection with poor visibility, and notify the driver. I do.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an image capturing unit that captures an image ahead of a vehicle, a road edge detecting unit that detects a road edge of a road surface on which the vehicle travels from the captured image, A vertical line segment detecting unit that detects a vertical line segment included in the image, and a dangerous scene detecting unit that detects a dangerous scene where the vertical edge intersects with the road edge, wherein the dangerous scene is detected. In this case, the driving assistance device notifies the driver of the presence of the dangerous scene.
[0007]
In the above-mentioned driving support device, it is preferable that the dangerous scene detection unit notifies the driver of the presence of the dangerous scene only when the moving speed of the detected dangerous scene with respect to the road surface is lower than a predetermined value.
[0008]
Further, the driving support device of the present invention further includes a vehicle state detecting means for detecting a speed and / or an acceleration of the vehicle, and when the vehicle is lower than a predetermined speed or decelerating, the presence of the dangerous scene is determined. It is preferable not to notify the driver.
[0009]
[Action]
On a general road, a place where a pedestrian or a bicycle is expected to jump out is a blind spot due to another vehicle or a wall at an intersection. When an image including such a dangerous scene is taken, the dangerous scene is composed of a vertical line segment and intersects a road edge in many cases. The driving support device of the present invention detects a road edge and a vertical line segment from an image photographed in front of the vehicle, detects a crossing point between the two, and identifies a danger scene. The scene can be accurately notified, and the safety of vehicle operation can be ensured.
[0010]
Further, the driving support device measures a moving speed of the detected dangerous scene with respect to the road surface, and notifies the driver of the presence of the dangerous scene only when the speed is lower than a predetermined value. As a result, it is possible to prevent erroneous recognition of a dangerous scene, and to suppress the driver from being notified of a detected dangerous scene with a low degree of danger, thereby reducing the troublesomeness of the notification.
[0011]
If the host vehicle is at or below a predetermined speed or is decelerating, it can be determined that the driver has an intention to stop or decelerate. In such a case, the driving assistance device suppresses notification of the detected dangerous scene to the driver, so that it is possible to reduce annoyance.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
First, FIG. 1 shows a typical example of an image photographed in front of a vehicle. FIG. 1A shows an intersection with poor visibility, and FIG. 1B shows an intersection with good visibility. Generally, an image of an intersection with poor visibility has a vertical line segment as shown in FIG. On the other hand, an image of an intersection with good visibility does not have a vertical line segment as shown in FIG. Therefore, by detecting this vertical line segment, it is possible to detect a dangerous scene that is a blind spot. Further, a vertical line segment caused by such a dangerous scene often intersects with a diagonal line representing a road edge (FIG. 1A). Therefore, it is possible to accurately detect a dangerous scene by detecting a point where a vertical line segment and a road edge in the image intersect.
[0013]
The vertical line segment considered to be a dangerous scene is often caused by a wall at an intersection, an entrance of a building, a stopped car, a telephone pole, and the like. The road edge is specified by a white line, a side gutter, or the like drawn on the boundary with the sidewalk.
[0014]
The basic operation of the driving support device according to the present invention will be described with reference to FIG. First, an image of the front of the vehicle is taken with a vehicle-mounted camera such as a CCD attached to the vehicle (101). Next, road edges and vertical line segments are detected from the captured images (102, 103). Then, a portion where the detected road edge intersects with the vertical line segment is detected to identify a dangerous scene (104). The driver is notified of the last detected danger scene (105).
[0015]
The road edge detection unit 102 detects a road edge in the following manner. First, an edge portion of luminance is detected by differentiating the photographed image to recognize an outline. Next, a road edge can be specified by detecting a pair of diagonal lines that converge toward the top of the screen from among the contours existing in the lower half of the image. At this time, if one of the pair of diagonal lines exists in the left half of the image and the other diagonal line exists in the right half, it is effective in preventing misidentification.
[0016]
FIG. 3 shows a specific scene of an image taken by the on-vehicle camera. When such an image is taken, the road edge 301 is detected first. At the same time, a vertical line segment is detected to identify a dangerous scene 302 where the two intersect. Dangerous scenes detected from this image include a shadow of the stopped vehicle 303, a blind spot due to an intersection wall, and a shadow of a telephone pole.
[0017]
Even at the point where the road edge intersects with the vertical line segment, the driver may not be blind spot. For example, 304 in FIG. 3 is not a blind spot of the driver. In such a case, the danger scene detection unit can determine the danger scene by comprehensively determining the positional relationship between the road edge and the vertical line segment and the like.
[0018]
When the dangerous scene 302 is detected, the presence of the dangerous scene is notified to the driver. At this time, the driver can be notified by voice and displayed on a vehicle-mounted display or a windshield.
[0019]
When detecting a dangerous scene, it is preferable to consider the moving speed of the vertical line obtained from the image with respect to the road surface. That is, when the detected vertical line segment is moving at a high speed, the vertical line segment is often caused by a car running in parallel, and such a case should not be regarded as a dangerous scene. On the other hand, if the detected moving speed of the vertical line relative to the road surface is smaller than the predetermined value, it can be regarded as a dangerous scene where a bicycle or a pedestrian is likely to jump out. Here, the predetermined value of the moving speed with respect to the road surface of the vertical line segment to be considered is not particularly limited, but may be, for example, 20 km / h.
[0020]
Although the driving assistance device described above is very useful with few misidentifications, a device that informs the driver of all danger scenes where the vehicle approaches may sometimes be troublesome for the driver. Specifically, this is a case where the driver is aware of a danger scene and is notified of the danger scene when the driver is appropriately decelerating or traveling at a sufficiently low speed.
[0021]
The embodiment of the present invention shown in FIG. 4 is to solve such a problem. The driving support device includes a vehicle state detection unit 402 that detects and outputs the speed and acceleration of the own vehicle, and determines whether or not the own vehicle is running in a dangerous state based on the output. The determination is made at 401. When it is determined that the own vehicle is traveling at a dangerous speed even though the dangerous scene is approaching, the dangerous driving determination unit 401 notifies the driver of the dangerous scene. On the other hand, when the host vehicle is running at a sufficiently low speed or decelerating, it is considered that the driver is aware of the dangerous scene, and no notification is made. This makes it possible to realize a driving support device that does not bother the driver.
[0022]
FIG. 5 is a diagram showing a processing flow of the driving support device in the embodiment of FIG. 4 described above. When the dangerous scene detection unit detects a dangerous scene (502), it is first determined whether or not the own vehicle is traveling at a predetermined speed or less, that is, at a safe speed (503). If the speed is safe, it is considered that the driver has already recognized the dangerous scene, so it is not necessary to notify the driver of the dangerous scene again. Even if the speed exceeds the safe speed, it is not necessary to notify the danger scene similarly if the own vehicle is decelerating (504). If the vehicle is not decelerating at a dangerous speed, it is considered that the driver has not noticed the dangerous scene, and the driver is notified of the dangerous scene (505).
[0023]
The safe speed described above differs depending on the location where the host vehicle is traveling. Therefore, as shown in FIG. 6, a safe speed is determined for each category of place, and it is determined whether the vehicle is running at a safe speed based on whether or not the speed exceeds this speed (503). . In this example, when a dangerous scene is detected while traveling at an intersection with poor visibility, the dangerous scene is given to the driver only when the speed of the own vehicle is 40 km / h or more and the vehicle is not decelerating. You will be notified. A scene in which the own vehicle is running as shown in FIG. 6 can be easily obtained by using a navigation system.
【The invention's effect】
According to the driving support device of the present invention, a dangerous scene at the place is detected by using a captured image, so that it is possible to appropriately determine a situation around the own vehicle and provide accurate information. Further, by considering the speed and acceleration of the host vehicle, it is possible to provide information that does not bother the driver.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of an image obtained by photographing the front of a vehicle.
FIG. 2 is a diagram showing a basic operation of the driving support device according to the present invention.
FIG. 3 is a more specific example of an image obtained by photographing the front of a vehicle.
FIG. 4 is a diagram showing a mode of reducing the burden on the driver.
FIG. 5 is a diagram showing a flow of a process for reducing annoyance of a driver.
FIG. 6 is a diagram illustrating a safe speed for each scene.
[Explanation of symbols]
101 Image photographing unit 102 Road edge detecting unit 103 Vertical line segment detecting unit 104 Danger scene detecting unit 105 Information providing device 301 Road edge 302 Danger scene 303 Stopped vehicle 401 Dangerous traveling determining unit 402 Vehicle state detecting means

Claims (3)

An image capturing unit that captures an image in front of the vehicle,
A road edge detection unit that detects a road edge of a road surface on which the vehicle travels from the captured image,
A vertical line segment detection unit that detects a vertical line segment included in the captured image,
A dangerous scene detection unit that detects a dangerous scene where the road edge and the vertical line segment intersect,
When the dangerous scene is detected, a driver is notified of the presence of the dangerous scene to a driver. The driving method according to claim 1, wherein the dangerous scene detection unit notifies the driver of the presence of the dangerous scene only when the moving speed of the detected dangerous scene with respect to the road surface is smaller than a predetermined value. Support equipment. The vehicle further includes a vehicle state detection unit that detects a speed and / or an acceleration of the vehicle, and does not notify a driver of the presence of the dangerous scene when the vehicle is lower than a predetermined speed or is decelerating. The driving support device according to claim 1 or 2, wherein

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