JP2000344006A - Road illuminating device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve road illumination and to reduce an accident at night by providing a drive control means for driving a road illuminating lamp to point to an illuminating direction determined by an image processing means. SOLUTION: As an image sensor 7, for example, a CCD camera is used and disposed in a substantially central position between head lamps 2, 3, for example, in a back mirror 9. The image sensor 7 obtains image information including an image of a road ahead according to the advance of a vehicle 1 and sends it to an image processor 6. Secondly, the image processor 6 processes the image information from the image sensor 7 to determine the illuminating direction of a road illuminating lamp 4, and transmits the information to a lamp driving control device 5 for directing the road illuminating lamp 4 toward the determined direction. The lamp driving control device 5 controls the drive of a stepping motor 8 in response to a lamp driving signal to turn the road illuminating lamp 4, thereby illuminating in the determined direction. Thus, lighting for the non-illuminated zone of the road can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a road lighting device for a vehicle, which drives and controls a road lighting lamp provided on a front surface of a vehicle in a predetermined lighting direction in accordance with image information from an image sensor. About.

[0002]

2. Description of the Related Art Currently, commercially available vehicle lighting devices include:
This is a front lighting device using a fixed headlamp. Because this device uses fixed headlamps,
Road lighting for various situations can only be performed incompletely. For example, when the vehicle rotates at night, the conventional lighting device cannot illuminate the driver so that the driver can clearly see a curved part of the road. Accordingly, various types of vehicle headlamp control devices are currently being developed.
These devices are all based on the control of the rotation of the headlamp according to the steering angle of the vehicle or its shaking rate. These prior art techniques utilize a steering angle sensor or shaking rate sensor to determine the desired lateral rotation of the headlamp. These conventional devices are usually controlled by a microcomputer and continuously process information from the sensors.

[0003]

One of the problems with the above-described apparatus is that it must process information in real time and send accurate and up-to-date information to a stepping motor for driving a headlamp. That is, these devices receive the information from the sensor and send the information to the stepping motor with a certain delay time, during which time a situation requiring the correction of the headlamp direction has already started. In other words, the conventional device cannot solve the above problem because it does not have the ability to predict the situation.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a new and original vehicle lighting device capable of reducing accidents occurring at night.

[0005]

In order to achieve the above object, a road lighting device for a vehicle according to the present invention includes a road lighting lamp provided on the front of a vehicle and image information of a road according to the progress of the vehicle. An image sensor for obtaining the image data, image processing means for determining an illumination direction of the road illumination lamp from the image information, and driving for driving the road illumination lamp in the illumination direction determined by the image processing means. And control means.

In the present invention, the road lighting lamp may be installed between head lamps installed on the left and right sides of the front of the vehicle.

In the present invention, the image sensor is a CCD
A camera may be attached to the rearview mirror.

In the present invention, the road lighting lamp is pivotally supported by a lamp holder around a horizontal axis and a vertical axis, and the lamp holder is rotated around a vertical axis by the drive control means. The lamp holder may be provided with a rotation adjusting means around the horizontal axis of the road lighting lamp.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A road lighting device for a vehicle according to the present invention comprises:
For example, it is configured as shown in FIGS. In the figure, 1 is a passenger car as a vehicle, 2 and 3 are left and right headlamps, 4 is a lamp for road illumination additionally provided in the present invention, 5 is a lamp drive control device, 6 is an image processing device , 7 are image sensors, and 8 is a stepping motor for rotating a road illumination lamp. Incidentally, the headlights 2 and 3 for illuminating a road ahead of the vehicle 1 may be used as the road illumination lamp 4.

The image sensor 7 uses, for example, a CCD camera, and is arranged at a substantially central position between the headlamps 2 and 3, for example, at a rear-view mirror 9. The image sensor 7 obtains image information including an image of a road ahead in accordance with the progress of the vehicle 1 and sends the image information to the image processing device 6.

The image processing device 6 includes, for example, a decoder (A
/ D converter) 6a, digital filter 6b, lane detecting device 6c, CPU 6d, signal transmitting device 6e, etc., and image information (analog signal) from image sensor 7
Is converted into a digital signal by the decoder 6a and supplied to the lane detecting device 6c via the digital filter 6b. The operations of the digital filter 6b, the lane detecting device 6c and the signal transmitting device 6e are controlled by the CPU 6d,
The lane detecting device 6c processes the digital filter signal to determine the illumination direction of the road illumination lamp 4 from the road image information according to the traveling of the vehicle, and to drive the road illumination lamp 4 in this direction. A signal is sent from the signal sending device 6e to the lamp drive control device 5.

The lamp drive control device 5 drives and controls the stepping motor 8 in response to the lamp drive signal, rotates the road illumination lamp 4 and illuminates the lamp 4 in the determined direction.

In the above-described apparatus of the present invention, the road lighting is performed by driving and controlling the added road lighting lamp 4 based on the analysis of the road image information by the image sensor (CCD camera). In addition, it is possible to perform ideal road illumination that cannot be achieved with the fixed headlamps 2 and 3 alone. In addition, since the rotation of the road illumination lamp 4 is controlled by predicting the progress of the vehicle by the image information analysis, optimal road illumination can always be performed.

Further, since the turning of the lamp 4 is controlled by knowing the state of the road on which the vehicle is not traveling yet, better road illumination is performed. In particular, if an edge detection method that detects the display of a lane mark on a road is used, the heading angle of the vehicle on the road surface can be effectively determined.

Further, since the illumination light of the road illumination lamp 4 is additionally superimposed on the illumination light of the conventional headlamps 2 and 3, the road illumination is greatly improved, and the illumination of the non-illuminated zone of the road is improved. improves.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the above-mentioned apparatus of the present invention will be described more specifically. First, the CCD camera 7 as an image sensor
For example, an analog black and white camera is used. This camera may be located anywhere between the headlamps 2 and 3 as shown in FIG. 1, but is mounted, for example, on the back side of the rearview mirror 9 (on the front side of the vehicle). The CCD camera 7 captures an image of the front of the road on which the vehicle 1 is traveling, and can continuously obtain information on the road condition on which the vehicle is traveling based on the obtained image signal. The lens of the CCD camera 7 is selected so as to effectively monitor the traveling road. For example, the horizontal field of view is 3
0 °, vertical field of view is 22 °. The image signal output from the CCD camera 7 is sent to the image processing device 6 and digitally processed for detecting a lane marker.

The edge detection filter in the lane detection device 6c detects the lane marker on the image plane by detecting the contrast of the pixel intensity between the white lane marker and the road plane. After independent point removal and noise reduction, curve fitting is used to extract road features.

The position of the vehicle between the lane boundaries is calculated based on the extraction of road features such as the radius of curvature of the road.
The desired lateral movement of the ramp 4 can be calculated from these road features.

The processed signal is sent to the lamp drive control device 5 by the signal sending device 6e. The lamp drive control device 5 converts the processed signal into a signal for rotating the additional light beam from the lamp 4.

For example, the rotation of the beam of the lamp 4 can be performed by rotating the lamp 4 itself.

FIGS. 3 and 4 show examples of the structure of the lamp 4. FIG.
In the figure, 4a is a lamp ball, 4b is a reflector, 4c is a lens, 4d is a lamp case, 4e is a lamp holder,
The lamp 4 is pivotally supported by a holder 4e so as to be rotatable about a vertical axis 4f and a horizontal axis 4g.

The rotation of the beam can be performed by rotating the reflector 4b or by another method.
Here, the correction of the lateral direction of the lamp is performed by rotating the lamp 4.

The lamp 4 is rotated around a vertical axis 4f by a stepping motor (which may be a DC motor) 8. As a result, the lateral movement range of the lamp is, for example, ±
Set to 30 °.

The lamp 4 can be directed vertically (vertically) around a horizontal axis 4g. This is performed by adjusting a screw (not shown) provided on the side surface of the lamp holder 4e. The direction of the light beam of the lamp 4 is screw 4h so as not to give intense light to the oncoming driver.
Is fixed downward by the adjustment of.

In FIG. 4, light from a lamp bulb 4a is reflected by a reflector 4b and distributed on a road by a lens 4c. The light beam generated by the lamp 4 is preferably narrow and of high intensity. This light beam is chosen to illuminate most of the traveling road lane, keeping it unobtrusive to other drivers and creating a bright spot on the road in front of the vehicle. This spot focuses the driver's attention and guides them with light,
Reduce nighttime traffic accidents.

FIG. 5 (a) shows road illumination by a conventional headlamp. In this case, only a low beam 31 pattern by a headlamp is generated for a lane marker 30 on the road.

However, according to the present invention, FIG.
As shown in (c), an additional beam 32 is added to the pattern of the low beam 31. As is clear from the figure, a bright spot P is generated in front of the low beam 31. FIG.
(C) shows that after the lateral control of the beam 32 of the ramp 4, the road is illuminated inside the curve.
Thus, the lateral control allows the driver to see parts of the road that could not be seen without this control. That is, the driver can see the road portion that the driver intends to enter.

Comparing FIG. 5 (a) with FIGS. 5 (b), (c), it is clear that the device of the present invention extends the driver's field of view at night.

In the present invention, it is important to pay attention to selecting a narrow beam because guiding by light is one of the objects of the present invention. However, it is also possible to use a broadened beam, which may be laterally wider than the low beam of a conventional headlamp. This wide beam makes it easier for drivers to see pedestrians and road signs.

As described above, after detecting the lane marker,
Curve fitting method
hod) is used for road feature extraction. This method is implemented, for example, from markers detected by using a second-order polynomial approximation.

The general form of a second order polynomial is given by: y = ax ² + bx + c Here, x and y correspond to positions on the image plane. The coefficients a, b and c are determined from the curve fitting method. The curve fitting method is realized only from lines provided outside (left) of the image plane. The correspondence between the image plane and the road plane must be determined in order to find the desired rotation of the ramp 4. It is determined by the geometry of perspective, a point of the road surface _P (X _p, Y _p) corresponds to the position of the image plane (x _p, y _p).

For example, the desired distance of a bright spot is _defined as Y _p
= 50 mm, the corresponding lateral deviation _Xp is calculated by equation 1 to match the corresponding position on the road. Equation 1 is used to give a point P on the imaginary centerline. The imaginary centerline is calculated from the left lane marker and the actual centerline. It corresponds to the middle line of the traveling lane. In this case, y-coordinate is chosen in the Y _p = 50 mm. This is because, as apparent from FIGS. 5B and 5C (point P), this corresponds to the distance at which the brightness of the ordinary low beam 31 needs to be increased. Then, a desired rotation angle of the lamp 4 is determined. The angle j is an angle determined by the center line of the image plane and the line (0P). Point 0 corresponds to the origin of the image plane. The center line of the image plane corresponds to the optical axis of the camera 7. After determining the angle j, the lamp 4 is driven to provide optimal road lighting.

[0033]

As described above, according to the present invention, the following effects can be obtained. (I) Accidents occurring at night can be reduced. (Ii) Safety is improved by always optimal road lighting. (Iii) Appropriate ramp control can be performed by predicting changes in road conditions due to the progress of the vehicle. (Iv) The device of the present invention can be added to existing lighting systems in vehicles without modification.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an embodiment of the apparatus of the present invention.

FIG. 3 is an explanatory diagram of a driving method of a road illumination lamp.

FIG. 4 is an explanatory diagram showing a configuration example of the lamp.

FIGS. 5A and 5B are explanatory diagrams of road lighting, in which FIG. 5A is a diagram illustrating conventional road lighting, and FIGS. 5B and 5C are diagrams illustrating road lighting according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle 2, 3 Headlamp 4 Roadway lamp 5 Lamp drive control device 6 Image processing device 7 Image sensor 8 Stepping motor 9 Rearview mirror

Claims (5)

[Claims] 1. A road illumination lamp provided on a front surface of a vehicle, an image sensor for obtaining image information of a road according to the progress of the vehicle, and an illumination direction of the road illumination lamp is determined from the image information. A road lighting device for a vehicle, comprising: an image processing unit configured to drive the road lighting lamp in a lighting direction determined by the image processing unit. 2. The vehicle road lighting device according to claim 1, wherein the road lighting lamp is installed between headlamps installed on the left and right of the front of the vehicle. 3. The image sensor is a CCD camera,
The vehicle road lighting device according to claim 1, wherein the vehicle road lighting device is attached to a rearview mirror. 4. The lamp for road illumination is pivotally supported by a lamp holder around a horizontal axis and a vertical axis, and the lamp holder is rotated around the vertical axis by the drive control means. 4. The vehicle road lighting device according to claim 1, wherein the vehicle road lighting device is configured. 5. The vehicle road lighting device according to claim 4, wherein said lamp holder is provided with a rotation adjusting means around a horizontal axis of said road lighting lamp.