JP2012051488A - Lamp control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lamp control device improving visibility of a front area on a snow road for securing safe travel on the snow road.SOLUTION: The lamp control device includes a road condition detecting means 1 for detecting that a road condition in which a vehicle travels is at least a snow covering condition and a light distribution control means 2 for reducing brightness of lighting of at least a part of the front area of the vehicle when the snow covering condition is detected. Or the lamp control device includes the light distribution control means 2 for lighting tracks detected in the front area of the vehicle more brightly than their surrounding area when the snow covering condition is detected.

Description

  The present invention relates to a lamp control device that detects a road situation in a front area of a host vehicle and controls light distribution of a lamp of the host vehicle based on the detected road situation.

  As a technique for automatically controlling the light distribution of a headlamp of an automobile, as described in Patent Document 1, lines on both sides of a travel route of the host vehicle (lanes, hereinafter referred to as white lines in the present specification) from an image obtained by imaging the front of the host vehicle ), A travel region of the host vehicle is recognized based on the detected white line, and a headlamp irradiation direction is controlled toward the recognized travel region. This technology is called the white line sensitive mode. In this white line sensitive mode, the driver's steering angle is used for safe driving because the driving area of the vehicle is reliably illuminated even when the driver performs an inappropriate steering. It can be said that it is preferable to the steering angle sensitive mode in which the irradiation direction of the headlamp is controlled corresponding to the above. However, this technique cannot be applied to a road situation in which a white line cannot be detected, for example, a road in which the white line is covered with snow, such as a snowy road where the road is covered with snow. On the other hand, Patent Document 2 proposes a technique for improving visibility on a snowy road by lighting an auxiliary lamp provided at a high position of the vehicle body when running on a snowy road.

JP-A-5-338487 JP-A-7-186824

In the technique of Patent Document 1, when a white line cannot be detected, for example, measures such as fixing the light distribution in the straight direction or fixing in the direction immediately before the white line cannot be detected are taken. There is no particular mention of the brightness. For this reason, if the headlamp illumination during driving on a snowy road remains in the normal driving state, the illumination light of the host vehicle is reflected by the snow on the road surface, which dazzles the driver of the preceding vehicle or the oncoming vehicle, or The driver of the vehicle is dazzled and the visibility of the front area, particularly the area just before, is reduced. Patent Document 2 is effective in preventing the visibility from being deteriorated due to the unevenness of snow on the road surface or the snow being attached to the lamp. However, the brightness of the headlamp is the same as that during normal driving. It is the same, and cannot prevent a decrease in visibility due to dazzling.

  An object of the present invention is to provide a lamp control device that improves visibility especially on snowy roads and ensures safe driving on snowy roads.

  According to a first aspect of the present invention, when a snow condition is detected by a road condition detecting unit that detects at least a snow condition as a road condition on which the vehicle travels, at least a part of the illumination in the front area of the host vehicle is detected. A light distribution control means for reducing the brightness is provided.

According to a second aspect of the present invention, a road detected by a road area detecting means for detecting at least a snowy situation as a road condition on which the vehicle is traveling is detected from the surroundings when the snowy situation is detected by the road area detecting unit. Further, the light distribution control means for illuminating brightly is provided.

  In the first aspect of the invention, when the vehicle travels on a snowy road, that is, the brightness of the front area is reduced, the reflected light of the illumination light due to snow is suppressed, and dazzling with respect to other vehicles is prevented and the driving of the host vehicle is performed. It also prevents dazzling people and improves visibility and ensures safe driving.

  In the second aspect of the present invention, when driving on a snowy road, a bag (wadder: a concave portion generated by a wheel) is illuminated brighter than the surroundings, so that the driver can easily see the bag and ensure safe driving.

The conceptual block diagram of the motor vehicle provided with the lamp | ramp control apparatus of this invention. Diagram showing headlamp configuration and illumination area The figure explaining the image analysis and light distribution control in a normal road condition. The figure explaining the image analysis and light distribution control in rainy / snowy road conditions. The figure explaining the image analysis and light distribution control in a snowy road condition.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a conceptual configuration diagram of an automobile according to an embodiment to which the present invention is applied. The car CAR includes a road condition detection device 1 that detects a road condition, particularly a road surface condition, based on an image obtained by an image pickup camera CAM for picking up a front area of the host vehicle, and the road condition detection apparatus. 1 is provided with a light distribution control device 2 for controlling the light distribution of a headlamp (headlight) HL that illuminates the front area of the vehicle based on the road condition detected in 1.

As shown in FIG. 2, the headlamp HL is composed of left and right headlamps RHL and LHL, each of which is a composite lamp having a plurality of light sources. Each headlamp RHL, LHL includes four lamp units in a lamp housing 3 constituted by a lamp body 31 and a front cover 32. The right headlamp RHL includes a high beam lamp unit Hi, a low beam lamp unit Lo, a right inner auxiliary lamp unit RI, and a right outer auxiliary lamp unit RO. The left head lamp LHL includes a high beam lamp unit Hi, a low beam lamp unit Lo, a left inner auxiliary lamp unit LI, and a left outer auxiliary lamp unit LO.

The left and right high beam lamp units Hi illuminate a wide range of the host vehicle with high beam light distribution, although not shown. Each of the left and right low beam lamp units Lo illuminates a low beam light distribution area ALo in the front area of the host vehicle as shown in FIG. The left inner auxiliary lamp unit LI of the left headlamp LHL illuminates a narrow left inner area ALI immediately before the host vehicle, and the left outer auxiliary lamp unit LO illuminates a left outer area ALO along the left side of the low beam light distribution area ALo. To do. Similarly, the right inner auxiliary lamp unit RI of the right headlamp RHL illuminates a narrow right inner area ARI immediately before the host vehicle, and the right outer auxiliary lamp unit RO is a right outer area along the right side of the low beam light distribution area ALo. Illuminate the ARO.

  Further, the left and right headlamps LHL and RHL are provided with a swivel device 4 for controlling deflection of the lamp optical axis to the left and right and a leveling device 5 for controlling deflection of the lamp optical axis up and down. Here, in each of the headlamps LHL and RHL, all the lamp units are integrally mounted on one frame 6, and this frame 6 is connected to the swivel device 4 and the leveling device 5 so as to be tiltable left and right, up and down, The light distribution control device 2 controls the swivel device 4 and the leveling device 5 so as to control the lamp optical axis from side to side and up and down.

The imaging camera CAM images the front area of the host vehicle and outputs the captured image to the road condition detection device 1. As this imaging camera CAM, a camera using a CCD imaging device or a MOS imaging device that has been conventionally used can be applied.

The road condition detection apparatus 1 includes an image analysis unit 11 that analyzes an image captured by the imaging camera CAM, and a road condition determination unit 12 that determines a road condition from the analyzed elements. The image analysis unit 11 scans the entire area of the captured image or the image area corresponding to the road to detect the luminance of each part (pixel). The road condition determination unit 12 detects a white line drawn on the road, a preceding vehicle or an oncoming vehicle existing in the front area of the host vehicle based on the detected luminance. Furthermore, a rainy weather situation or a snowfall situation where the road surface is wet is detected based on the detected luminance. In particular, in the present invention, when a minute high-luminance point is detected over the upper region or the entire region of the image, it is determined that the illumination light of the host vehicle is a luminance point reflected by snowfall, and it is determined that it is a snowfall situation. . In addition, when a high brightness area is detected over a wide area in the lower half of the image, it is determined that the illumination light of the host vehicle is a brightness point reflected by snow on the road surface. When the region is detected, it is determined that the snow is in a snowy state because it is a luminance point due to snow on the shoulder of the road.

The light distribution control device 2 controls the brightness (luminosity) of each lamp unit of the headlamp HL and the left and right based on the road condition output from the road condition detection device 1. The headlights LHL and RHL swivel device 4 and leveling device 5 are controlled to control the lamp optical axes of the headlamps LHL and RHL left and right and up and down.

(Normal road condition judgment)
According to the above configuration, the imaging camera CAM images the front area of the host vehicle, and the road condition detection device 1 performs image analysis based on the captured image to determine the road condition. For example, in FIG. 3A, the image analysis unit 11 detects a white line WL or a street light STL drawn on the road surface, and at the same time, a tail lamp or head of another vehicle (preceding vehicle or oncoming vehicle) existing in front of the host vehicle. When the OL such as a lamp is detected, the road condition determination unit 12 determines that the passing road condition is present. In response to this determination, the light distribution control device 2 turns on the low beam lamp units Lo of the left and right headlamps LHL and RHL at the normal light intensity by the light intensity control unit 21, and the light distribution control unit 22 sets the lamp optical axis to the white line WL. A so-called white line sensitive mode is automatically set in the direction along the direction, and the swivel device 4 controls the deflection of the lamp optical axis of each low beam lamp unit Lo to the left and right. As a result, as shown in FIG. 3B, the low beam lamp unit Lo illuminates the front low beam light distribution area ALo along the white line WL, ensuring the visibility of the front area by the driver and ensuring safe driving. . Although illustration is omitted, it is possible to determine that the vehicle is in a traveling road state when no other vehicle is detected in the determination by the road state determination unit 12, and to perform control to turn on the high beam lamp unit Hi.

(When judging rain / snow conditions)
When the image analysis unit 11 detects that the area FA of the host vehicle is high in brightness and the area is wet and the road condition determination unit 12 determines the rain condition, or as shown in FIG. The image analysis unit 11 detects the high brightness point PL due to the light reflection from the snow particles in the upper region or the entire region of the image, and the road condition detection unit 12 is snowing. When the situation is determined, the light distribution control device 2 causes the light intensity control unit 21 to slightly reduce the light intensity of the low beam lamp unit Lo. As a result, as shown in FIG. 4 (b), the brightness of the low beam light distribution area ALo in the area immediately before the own vehicle is reduced, and the reflected light of the headlamp of the own vehicle from the wet road surface in this area causes It prevents dazzling, or prevents the driver of the own vehicle from being dazzled by this reflected light and reducing its visibility. At this time, if the white line WL is detected, it goes without saying that the swivel device 4 is controlled in the white line sensitive mode and the lamp optical axis is controlled to follow the white line.

When the snowfall is severe, the light distribution control unit 22 controls the leveling device 5 to deflect the lamp optical axis downward. Thereby, it is suppressed that the light of the low beam lamp unit Lo is reflected in a scattered state by snow particles at a high position in the immediately preceding region of the host vehicle, in particular, at a height position of the line of sight of the driver of the host vehicle. Ensure the visibility of the driver of the vehicle.

(When judging snow condition 1)
As shown in FIG. 5A, when the image analysis unit 11 detects a high-luminance surface in the lower area FA1 in a wide range of the image, and the road condition determination unit 12 determines a snowy condition where snow has accumulated on the road, The control device 2 causes the light intensity control unit 21 to lower the light intensity of the low beam lamp unit Lo as compared with when it is raining. That is, the light reflection on the road surface becomes larger than that in rainy weather due to snow on the road surface, so that the brightness of the low beam light distribution area ALo is lowered as shown in FIG. This prevents the other vehicle from being dazzled by the light reflection on the road surface of the low beam light distribution area ALo, and the driver's visibility in the host vehicle from being deteriorated. At the same time, the luminous intensity control unit 21 lights the left and right inner auxiliary lamp units LI and RI of the left and right headlamps LHL and RHL with brighter illumination than the low beam lamp unit Lo. As shown in FIG. 5B, the left inner auxiliary lamp unit LI illuminates a narrow area ALI in the left area with respect to the left and right center of the vehicle, and the right inner auxiliary lamp unit RI similarly has a narrow area ARI in the right area. Illuminate. The illumination areas ALI and ARI of the left and right inner auxiliary lamp units LI and RI are set to the treads (distance dimensions of the left and right tires) of general automobiles including small cars to large cars in the horizontal dimension. Each of the inner auxiliary lamp illumination areas ALI and ARI illuminates the eaves W generated on the road surface covered with snow by the preceding vehicle. Therefore, the driver can easily see 轍 W in the brightly lit left and right inner lamp illumination regions ALI and ARI in the low beam light distribution region ALo where illumination is reduced, and the driver can perform his own steering by following the 轍 W. The vehicle can be advanced along the heel W, and safe driving is possible. In this case, since a white line cannot be detected due to snow accumulation, the light distribution control unit 22 is set to a steering angle sensitive mode in which the lamp optical axis is deflected to follow the steering angle, and the low beam lamp unit Lo and each of the left and right The optical axes of the inner auxiliary lamp units LI and RI can be deflection-controlled following the steering, and in particular, the inner auxiliary lamp illumination areas AL and AR can be illuminated while following the 轍 W. Thereby, in particular, it is possible to prevent obstacles such as derailment on snowy mountain roads.

  When the snow condition determination 1 is performed, if the image analysis unit 11 can detect the wing W based on the image captured by the imaging camera CAM in the front area illuminated by the low beam lamp unit Lo, the light distribution control is performed. The light distribution control unit 22 of the apparatus 2 may follow the detected ridge W and control the deflection of the lamp optical axis. This deflection control can be realized by replacing the white line in the white line sensitive mode with 轍. In this way, the low beam distribution area ALo and the left and right inner auxiliary lamp illumination areas ALI and ARI can follow the 轍 W to illuminate the 轍 W brightly, thereby ensuring safe driving by the driver. .

(When judging snow condition 2)
When the image analysis unit 11 detects the snow cover state in the same manner as in the snow cover state determination 1 and detects the road shoulder region SH as shown in FIG. 5A as a high brightness, the light intensity control unit 21 performs the low beam lamp unit. The light intensity of Lo is lowered as compared with the case of rainy weather as in the case of snowy condition judgment 1. At the same time, as shown in FIG. 5 (c), the light distribution control device 2 when the hail W in the front area of the host vehicle cannot be detected or when the detected hail W is not clear as shown in FIG. The light intensity control unit 21 lights the outer auxiliary lamp units LO, RO of the left and right headlamps LHL, RHL with illumination brighter than that of the low beam lamp unit Lo. Since the outer auxiliary lamp units LO and RO illuminate the left or right shoulder area SH of the road on which the vehicle is traveling, the driver can visually recognize the left and right shoulder areas SH even if he / she cannot confirm the saddle. Steering enables safe driving. Further, the low beam lamp unit Lo and the outside auxiliary lamp units LO and RO are controlled to follow the detected road shoulder area SH or follow the steering, and the low beam light distribution area ALo and the both outside auxiliary lamp illumination areas ALO are controlled. , ARO may be appropriately illuminated. It is possible to check the puddle that is generated in the left and right shoulder areas SH on a mountain road or the like, and it is possible to prevent an accident from derailing and entering the puddle.

  In the above embodiment, the brightness of the image captured by the imaging camera is detected, and the road condition is detected based on the luminance distribution, the brightness level, etc., but in the case of a color imaging camera, the road condition of snowfall or snowfall is detected. When determining, it is also possible to determine from the distribution of the white portion of the image. Moreover, it is also possible to detect the output of various sensors such as a temperature sensor and a raindrop sensor that detect the temperature and the road surface temperature without using an imaging camera. In particular, when the temperature of the outside air temperature is close to 0 ° C., it is determined that the snowfall situation or the snowfall situation is present.

  In the embodiment, the headlamp is controlled to be deflected based on the detected hail or snow on the shoulder, or the deflection is controlled to follow the steering angle. It is possible to achieve the effects of the present invention simply by configuring as described above.

  The present invention can be adopted as long as it is a lamp control device that detects a road condition on which the host vehicle travels and controls the light distribution of the lamp of the host vehicle, particularly the headlamp, based on the road condition.

DESCRIPTION OF SYMBOLS 1 Road condition detection apparatus 2 Light distribution control apparatus 3 Lamp housing 4 Swiveling apparatus 5 Leveling apparatus 11 Image analysis part 12 Road condition determination part 21 Light intensity control part 22 Light distribution control part HL (LHL, RHL) Headlamp Hi High beam lamp unit Lo Low beam lamp unit LI, RI Inside auxiliary lamp unit LO, RO Outside auxiliary lamp unit CAR Car CAM Imaging camera

Claims (2)

Light distribution control means for reducing the brightness of at least part of the illumination in the front area of the host vehicle when the snow condition is detected by a road condition detection means for detecting at least a snow condition as a road condition on which the vehicle is traveling A lamp control device comprising: A light distribution control means for illuminating the hail detected in the front area of the host vehicle when the snow condition is detected by a road condition detection means for detecting at least a snow condition as a road condition on which the vehicle travels; A lamp control device comprising the lamp control device.

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