JP2008230333A - Driving assisting device of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the visibility of pedestrians and the like in front of a vehicle. <P>SOLUTION: In this driving assisting device of a vehicle, ultraviolet rays are emitted toward a target existing in front of a vehicle (ST160). The ultraviolet rays are reacted to highlight the target, so that a driver can clearly recognize the target in front of the vehicle. However, for example when the target does not contain fluorescence agent, the target might not be highlighted even by emitting the ultraviolet rays. Therefore, it is judged whether the driver can visually recognize the target radiated with the ultraviolet rays or not (ST170), and when it is judged that the target cannot be recognized, visible lights are emitted to the target (ST190). Thus, the driver can easily recognize the target which is difficult to visually recognize even with emission of the ultraviolet rays. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a driving support device for a vehicle, and more particularly to a technique for improving the visibility of a driver with respect to a pedestrian or the like ahead of the vehicle.

In recent years, the automobile industry has been working on the development and evolution of various technologies and equipment that enhance the safety performance of cars in order to realize a safe automobile society. One of them is a technique of providing a headlamp that irradiates ultraviolet light in front of a vehicle in order to improve visibility for a pedestrian ahead when traveling at night (see Patent Documents 1 and 2). According to this, the ultraviolet light reacts to the clothes of the pedestrian in front and makes this pedestrian rise clearly, so that the driver can clearly recognize the pedestrian in front.
Japanese Unexamined Patent Publication No. 2000-203335 JP 2000-027128 A

  However, in both Patent Documents 1 and 2, the irradiation direction of ultraviolet light is set in advance and fixed. In Patent Document 1, the irradiation range of the UV light 9 is set so as to irradiate only the outer side in the vehicle width direction with respect to the vehicle body center axis of the host vehicle 1 [0014]. In Patent Document 2, the ultraviolet light output device 2B is always set in an upward illumination state [0015] [0018] [FIG. 5].

  An object of the present invention is to provide a driving support device for a vehicle that can improve visibility for a pedestrian or the like ahead of the vehicle.

  The vehicle driving support apparatus according to the present invention includes a target detection unit that detects a target in front of the vehicle, a UV irradiation unit that irradiates ultraviolet light toward the target detected by the target detection unit, and the UV. Visibility determination means for determining whether the vehicle driver can visually recognize a target to which ultraviolet light from the irradiation means is directed, and a target determined to be unrecognizable by the visibility determination means And a visible light irradiation means for irradiating visible light.

  In the vehicle driving support device, ultraviolet light is irradiated toward a target existing in front of the vehicle. Since the ultraviolet light reacts to lift the target, the driver can clearly recognize the target in front. However, in some cases, such as when the target does not contain a fluorescent agent, the target may not rise even when irradiated with ultraviolet light. Therefore, in the vehicle driving support device, it is determined whether or not the driver can visually recognize the target irradiated with the ultraviolet light, and when it is determined that the target cannot be recognized, the target is visible toward the target. Irradiate light. Thereby, even if it irradiates with ultraviolet light, it becomes easy to recognize the target which is difficult to recognize by the driver's visual observation.

  Preferably, the vehicle driving support apparatus further includes a collision prediction unit that determines a possibility of a collision with the host vehicle with respect to the target detected by the target detection unit, and the UV irradiation unit includes the collision prediction unit. Irradiate ultraviolet light toward a target that is determined to have a potential for collision.

  Preferably, the target detection means includes a radar that transmits a radar wave toward the front of the vehicle and receives a reflected wave from the front of the vehicle, and an infrared camera that images the front of the vehicle with infrared rays, The radar and the infrared camera are used to detect a target in front of the vehicle, and the vehicle driving support device further determines whether the target detected by the target detection means is a pedestrian. Pedestrian discrimination means for judging whether or not is provided.

  Preferably, the UV irradiation means sets the irradiation output level of the ultraviolet light to the first level when the pedestrian determination means determines that the target detected by the target detection means is not a pedestrian, When the pedestrian discrimination means determines that the target is a pedestrian, the ultraviolet light irradiation output level is set to a second level lower than the first level.

  Preferably, the driving support apparatus for a vehicle further includes an oncoming vehicle detection unit that detects an oncoming vehicle with respect to the host vehicle, and a control unit that controls on / off of visible light irradiation by the visible light irradiation unit. The means turns on the visible light irradiation by the visible light irradiation means when the oncoming vehicle is not detected by the oncoming vehicle detection means when there is a target determined to be unrecognizable by the visibility determination means. .

  Preferably, the vehicle driving support apparatus further includes alarm means for generating an alarm in response to an instruction from the control means, and the control means is a target determined to be unrecognizable by the visibility determining means. When the oncoming vehicle is detected by the oncoming vehicle detection means, the visible light irradiation by the visible light irradiation means is turned off and the alarm means is instructed to generate an alarm.

  Preferably, the UV irradiation means is composed of a high beam unit of headlamp means for irradiating visible light ahead of the vehicle.

  Preferably, the UV irradiation means is configured separately from the headlamp means for irradiating visible light ahead of the vehicle.

  According to the present invention, since the target is not lifted up even when the target is detected by the target detection means, even if the target is not lifted up, the visible light is irradiated. Easy to recognize. This is particularly effective when the target does not contain a fluorescent agent and does not lift up when irradiated with ultraviolet light.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, substantially the same parts are denoted by the same reference numerals, and description thereof will not be repeated.

[System configuration]
FIG. 1A shows a system configuration of a vehicle driving support apparatus according to an embodiment of the present invention. The driving support device includes a radar 10, an infrared camera 20, a visible camera 30, a yaw rate sensor 40, a vehicle speed sensor 41, an ECU (Electronic Control Unit) 50, actuators 60, 70, 100, and a UV light. 80, 90, a visible light 110, and an alarm device 120.

  The radar 10 transmits a radar wave toward the front of the vehicle and receives a reflected wave from the front of the vehicle. The infrared camera 20 images the front of the vehicle with infrared rays. As shown in FIGS. 1B and 1C, the radar 10 is disposed near the front grille at the front of the vehicle, and the infrared camera 20 and the visible camera 30 are disposed at the front front end of the vehicle interior. Using the radar 10 and the cameras 20 and 30, the distance to the target ahead of the vehicle, the shape of the target, the direction of the target, and the like are detected. The vehicle speed sensor 41 detects the traveling speed of the host vehicle. The yaw rate sensor 40 detects the yaw rate of the host vehicle, and estimates the traveling path of the host vehicle together with the vehicle speed sensor 41. The ECU 50 is a computer that performs various arithmetic processes for driving support.

  The UV lights 80 and 90 are respectively arranged on the left and right of the front part of the vehicle, and irradiate the front of the vehicle with ultraviolet light. It is preferable to use ultraviolet light irradiated from the UV lights 80 and 90 having a wavelength of 315 nm or more. This is because it is classified as UV-A and has almost no influence on the human body.

  The actuators 60 and 70 control the irradiation direction of the ultraviolet light emitted from the UV lights 80 and 90. The actuators 60 and 70 control the irradiation output level of ultraviolet light emitted from the UV lights 80 and 90.

  The visible light 110 is disposed at the front of the vehicle and irradiates visible light ahead of the vehicle. The actuator 100 controls the irradiation direction of visible light emitted from the visible light 110.

  The alarm device 120 generates an alarm by voice toward the driver of the vehicle and the pedestrian in front of the vehicle.

[Mounting form of UV light 80, 90, visible light 110]
There are “independent type” and “headlight built-in type” as mounting forms of the UV lights 80 and 90.

  In the “independent type”, as shown in FIG. 1B, the UV lights 80 and 90 are configured separately from the headlamp 130 that irradiates visible light (high beam, low beam) in front of the vehicle. Ultraviolet light is emitted from the light source bulb 81 of the UV light 80, and this ultraviolet light is reflected to the front of the vehicle by the movable reflector 82. The actuator 60 controls the irradiation direction of the ultraviolet light by rotating the movable reflector 82 in the vertical direction and the horizontal direction. The same applies to the internal structure and operation of the UV light 90.

  The visible light 110 is arranged at the center of the front portion of the vehicle and is configured separately from the headlamp 130. Visible light is emitted from the light source bulb 111 of the visible light 110, and the visible light is reflected to the front of the vehicle by the movable reflector 112. The actuator 100 controls the irradiation direction of visible light by controlling the movable reflector 112 to rotate in the vertical direction and the horizontal direction.

  In the “headlight built-in type”, as shown in FIG. 1 (c), the UV lights 80 and 90 are constituted by a high beam unit of the headlamp 130. Although not only ultraviolet light but also visible light is emitted from the light source bulb 81, only the ultraviolet light is transmitted through the filter 83 and is irradiated to the front of the vehicle. Further, similarly to the “independent type”, the irradiation direction of the ultraviolet light is controlled by the actuators 60 and 70. The filter 83 functions only when irradiating ultraviolet light in front of the vehicle, and does not function when irradiating visible light (high beam) in front of the vehicle. Moreover, the control of the irradiation direction by the actuators 60 and 70 is performed only when the ultraviolet light is irradiated to the front of the vehicle, and is not performed when the visible light (high beam) is irradiated to the front of the vehicle. This is because oncoming cars are dazzling.

  The visible light 110 is composed of a low beam unit of the headlight 130.

  As for the mounting form of the visible light 110, the form shown in FIG. 1B and the form shown in FIG. 1C can be interchanged.

  Further, the low beam unit of the headlamp 130 is configured such that the irradiation optical axis is movable in the vertical and horizontal directions by an actuator according to the steering angle of the vehicle (Adaptive Front Lighting System).

[Operation flow]
Next, the operation of the vehicle driving support apparatus configured as described above will be described with reference to the flowchart of FIG.

[ST100]
Based on information from the vehicle speed sensor 41 and the yaw rate sensor 40, the ECU 50 estimates the traveling path of the host vehicle. A target existing ahead of the estimated traveling path is detected by the radar 10 and the cameras 20 and 30. The ECU 50 calculates the distance to the detected target, the shape of the target, the moving direction of the target, the moving speed of the target, and the like.

  The traveling path of the host vehicle may be estimated using a steering angle sensor, a steering angular velocity sensor, or the like.

[ST110]
Next, the ECU 50 determines whether or not each detected target has a possibility of a collision with the host vehicle. The determination of the possibility of collision is performed based on information such as the movement speed / trajectory of the target and the movement speed / trajectory of the host vehicle.

[ST120]
Next, the ECU 50 designates a target to be irradiated with ultraviolet light (UV irradiation target) by the UV lights 80 and 90 from the targets determined as “possibility of collision” in step ST110.

  When there are a plurality of targets determined as “possibility of collision” in step ST110, the ECU 50 prioritizes these targets. The priority order is determined based on the degree of danger to the host vehicle. As an index representing the degree of danger to the host vehicle, for example, the proximity to the host vehicle or the degree of collision possibility can be used. When there is one target determined as “possibility of collision” in step ST110, the ECU 50 gives the highest priority to the target. Then, a target to be irradiated with UV (ultraviolet light) is designated based on the priority order and the UV irradiation pattern. As the UV irradiation pattern, for example, as shown in FIG. 3, the target 210 having the highest priority is irradiated with the UV light 90 on the same side as the target 210, and the target 220 having the second highest priority is reversed. Various irradiation patterns such as irradiation with the side UV light 80 can be realized.

[ST130]
Next, the ECU 50 determines whether or not the target designated as the UV irradiation target in step ST120 is a pedestrian. The determination as to whether or not the person is a pedestrian can be made, for example, by checking whether or not the ratio between the height and width of the detected target is within a predetermined range.

[ST140]
When it is determined in step ST120 that the target designated as the UV irradiation target is a pedestrian, the ECU 50 causes the actuators 60 and 70 to set the irradiation output level of the UV lights 80 and 90 to the “weak” level. Give instructions. In response to this, the actuators 60 and 70 set the irradiation output level of the ultraviolet light emitted from the UV lights 80 and 90 to the “weak” level. Here, the “weak” level is an irradiation output level that is considered to have (almost) no influence on the human body by the irradiated ultraviolet light. Thus, when the target of UV irradiation is a pedestrian, the irradiation output of ultraviolet light is set low, so that the influence on the human body is small and safe.

[ST150]
On the other hand, when it is determined in step ST120 that the target designated as the UV irradiation target is not a pedestrian, the ECU 50 sets the irradiation output level of the UV lights 80 and 90 to the “strong” level. An instruction is issued to 70. In response to this, the actuators 60 and 70 set the irradiation output level of the ultraviolet light emitted from the UV lights 80 and 90 to the “strong” level. The “strong” level here is a predetermined level higher than the “weak” level.

[ST160]
In step ST120, control for irradiating ultraviolet light from the UV lights 80 and 90 toward the target designated as the UV irradiation target is performed.

  For example, as shown in FIG. 3, the target 210 having the highest priority is irradiated with the UV light 90 on the same side as the target 210, and the target 220 having the second highest priority is irradiated with the UV light 80 on the opposite side. In the case of the UV irradiation pattern to be irradiated, the following control is performed.

  The ECU 50 determines whether the target 210 with the highest priority in step ST120 is on the left or right side with respect to the vehicle center axis. Here, it is determined that it exists on the right side as shown in FIG. Next, the ECU 50 calculates a light distribution angle for directing the ultraviolet light irradiated from the UV light 90 on the side corresponding to the determination result, here, the right side to the target 210. Based on the light distribution angle calculated by the ECU 50, the actuator 70 controls the rotation of the movable reflector 82, and the ultraviolet light from the UV light 90 is irradiated toward the target 210. On the other hand, the ECU 50 distributes the ultraviolet light emitted from the UV light 80 on the side opposite to the determination result, here the left side, to the target 220 having the second highest priority in the step ST120. Calculate the corner. Based on the light distribution angle calculated by the ECU 50, the actuator 60 controls the rotation of the movable reflector 82, and the ultraviolet light from the UV light 80 is irradiated toward the target 220.

  The UV irradiation pattern is merely an example of control, and it goes without saying that various irradiation patterns can be realized.

[ST170]
Next, the ECU 50 determines whether or not the driver can visually recognize the target irradiated with the ultraviolet light in step ST160. The ECU 50 performs image processing (edge processing or contrast processing) on an image obtained by capturing the target with the visible camera 30 and sets a criterion for determining that the image will be visible to the driver at this level. The determination is made based on a comparison between the subsequent image and the determination criterion.

[ST180]
When it is determined in step ST170 that the vehicle cannot be recognized, the ECU 50 determines whether there is an oncoming vehicle for the host vehicle based on information from the radar 10 and the cameras 20 and 30.

[ST190]
When it is determined in step ST180 that there is no oncoming vehicle, the ECU 50 sets the light distribution angle for directing the visible light emitted from the visible light 110 to the target determined to be unrecognizable in step ST170. calculate. Based on the light distribution angle calculated by the ECU 50, the actuator 100 controls the rotation of the movable reflector 112 to turn on the visible light irradiation from the visible light 110. Thereby, the visible light from the visible light 110 is irradiated toward the target. The flow of visible light irradiation by the visible light 110 is shown in FIG. As described above, in the vehicle driving support apparatus according to the present embodiment, the target 300 does not rise even when the ultraviolet light is irradiated even though the target 300 that may collide is detected in front of the vehicle. Visible light is emitted from the visible light 110 toward the target 300 when the driver cannot visually recognize the target 300, so that the driver can easily recognize the target 300.

[ST200]
On the other hand, if it is determined in step ST180 that there is an oncoming vehicle, the visible light irradiation by the visible light 110 is not performed (the visible light irradiation from the visible light 110 is kept off), and an alarm generation process is performed. Is done. The alarm generation process is performed according to the flow shown in FIG.

[ST201]
ECU50 determines whether the target used as the irradiation object of the ultraviolet light by UV light 80,90 is a pedestrian. This determination uses the determination result in step ST130.

[ST202, ST203]
When it is determined in step ST201 that the person is not a pedestrian, the ECU 50 turns off the pedestrian warning function and the PCS warning function by the warning device 120.

[ST204]
When it is determined in step ST201 that the user is a pedestrian, the ECU 50 determines whether there is a pedestrian crossing in the vicinity of the pedestrian. This determination is performed using an image captured by the visible camera 30, various information by the navigation device, and the like.

[ST205]
When it is determined in step ST204 that there is a pedestrian crossing, the ECU 50 determines whether or not a pedestrian signal near the pedestrian crossing is red. This determination is performed using an image captured by the visible camera 30, various information by the navigation device, and the like.

[ST206]
If it is determined in step ST204 that there is no pedestrian crossing and if it is determined in step ST205 that the pedestrian signal is red, the ECU 50 instructs the alarm device 120 to sound a pedestrian alarm. In response to this instruction, the alarm device 120 generates an ultrasonic alarm toward the pedestrian 400 that is irradiated with ultraviolet light from the UV light 90, as shown in FIG. This alarm is performed using a super-directional sound source, and audible sounds such as a horn sound, an automobile engine sound, and an audible voice announcement are converted into ultrasonic waves and emitted toward the pedestrian 400. As a result, the alarm is reliably delivered to the ears of the pedestrian 400 who does not notice the car. In recent years, there have been many accidents in which elderly people cross over without a pedestrian crossing without noticing the car, but such an accident can be effectively prevented by using the alarm.

[ST207]
Next, the ECU 50 instructs the alarm device 120 to sound a PCS alarm. In response to this instruction, the alarm device 120 generates an alarm by voice to the driver.

[ST208, ST209]
If it is determined in step ST206 or ST207 that a collision with a pedestrian cannot be avoided despite the occurrence of an alarm, the ECU 50 operates a PCS (pre-crash safety system) to reduce damage.

  INDUSTRIAL APPLICABILITY The present invention is useful as a driving assistance device for improving the visibility of a driver of a vehicle, particularly for improving the visibility of a pedestrian and an obstacle ahead when traveling at night.

FIG. 1A is a block diagram showing a system configuration of a vehicle driving support apparatus according to an embodiment of the present invention. (b) And (c) is a figure which shows the mounting form of UV light and visible light. It is a flowchart which shows the flow of operation | movement of the driving assistance device of the vehicle by embodiment of this invention. It is a figure which shows the irradiation pattern of an ultraviolet light. It is a figure which shows the flow of visible light irradiation. It is a flowchart which shows the flow of an alarm generation process. It is a figure which shows an example of the warning to a pedestrian.

Explanation of symbols

10 Radar 20 Infrared camera 30 Visible camera 40 Yaw rate sensor 41 Vehicle speed sensor 50 ECU (Electronic Control Unit)
60,70,100 Actuator 80,90 UV light 110 Visible light 81,111 Light source bulb 82,112 Movable reflector 83 Filter 120 Alarm device 130 Headlight 210-230,300 Target 400 Pedestrian

Claims (8)

Target detection means for detecting a target in front of the vehicle;
UV irradiation means for irradiating ultraviolet light toward the target detected by the target detection means;
Visibility determination means for determining whether or not the driver of the vehicle can visually recognize a target to which ultraviolet light from the UV irradiation means is directed;
Visible light irradiation means for irradiating visible light toward a target determined to be unrecognizable by the visibility determination means,
A vehicle driving support device characterized by the above. In claim 1,
A collision prediction means for judging the possibility of a collision with the host vehicle for the target detected by the target detection means;
The UV irradiation means includes
Irradiating ultraviolet light toward a target that is determined to have a possibility of collision by the collision prediction means,
A vehicle driving support device characterized by the above. In claim 1 or 2,
The target detection means is
A radar unit for transmitting a radar wave toward the front of the vehicle and receiving a reflected wave from the front of the vehicle;
Including an infrared camera for imaging the front of the vehicle with infrared rays,
Using the radar unit and the infrared camera to detect a target in front of the vehicle;
The vehicle driving support device further includes:
Pedestrian discrimination means for judging whether the target detected by the target detection means is a pedestrian,
A vehicle driving support device characterized by the above. In claim 3,
The UV irradiation means includes
When the target detected by the target detection means is determined not to be a pedestrian by the pedestrian discrimination means, the irradiation output level of the ultraviolet light is set to the first level, and the target is a pedestrian. When judged by the pedestrian discrimination means, the irradiation output level of ultraviolet light is set to a second level lower than the first level,
A vehicle driving support device characterized by the above. In any one of Claims 1-4,
An oncoming vehicle detection means for detecting an oncoming vehicle relative to the host vehicle;
Control means for controlling on / off of visible light irradiation by the visible light irradiation means,
The control means includes
Turning on the visible light irradiation by the visible light irradiation means when the oncoming vehicle is not detected by the oncoming vehicle detection means when there is a target determined to be unrecognizable by the visibility determination means;
A vehicle driving support device characterized by the above. In claim 5,
Alarm means for generating an alarm in response to an instruction from the control means;
The control means includes
When an oncoming vehicle is detected by the oncoming vehicle detection means when there is a target determined to be unrecognizable by the visibility determination means, the visible light irradiation by the visible light irradiation means is turned off and the alarm is issued. Instruct the means to generate an alarm,
A vehicle driving support device characterized by the above. In any one of Claims 1-6,
The UV irradiation means includes
Consists of a high beam unit of headlamp means that radiates visible light ahead of the vehicle,
A vehicle driving support device characterized by the above. In any one of Claims 1-6,
The UV irradiation means includes
It is configured separately from the headlamp means for irradiating visible light ahead of the vehicle,
A vehicle driving support device characterized by the above.

Images