JP3203957B2 - Lane departure warning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lane departure warning device, and more particularly to a device for warning a vehicle departure from a lane (white line, yellow line) by monitoring the road surface condition immediately before the vehicle with a line camera or the like. It is.

[0002]

2. Description of the Related Art JP-A-59-128693 or JP-A-3-27
In the lane departure warning device conventionally known from Japanese Patent No. 3498, etc., a camera serving as a lane detecting means takes an image of the front of the vehicle, and the obtained image signal is binarized by a signal processing means so that the signal on the road surface is obtained. Is extracted, and when the distance between the lane and the vehicle is in a dangerous state of a predetermined value or less, if the direction instruction operation is not performed, the alarm device is activated to generate an alarm.

A headlight of a vehicle equipped with such a lane departure warning device is usually used to secure a night view field a by a driver's eye point EP as shown in FIGS. 5 (1) and 5 (2). It is designed and mounted, and its irradiation range b (shaded area) of the headlight 2 is limited to the driver's field of view a as shown in FIG.

On the other hand, in such a lane departure warning device,
In order to accurately and accurately detect the deviation of the vehicle 10 from the lane, it is necessary to set the sensor field of view c of the lane detecting means 1 to a position immediately before (immediately before) the front of the vehicle.

[0005] For this reason, during night driving, a warning process must be performed only in the range of a few meters from the front end of the vehicle to be detected as a lane detection target only by accidentally leaking light.

Accordingly, in such a conventional example, the area immediately in front of the vehicle is illuminated only by accidental leakage light.
The lane detection at night cannot be accurately performed, and the function of the lane departure warning device cannot be achieved.

To solve such a problem, there is a method of adding an auxiliary headlamp (auxiliary illumination) such as a fog lamp. However, in the case of a visible light, the number and the mounting position of the auxiliary headlamp are determined according to a vehicle security standard. In addition, in a vehicle in which a main headlight and an auxiliary headlight, which are popular in recent years, are integrated, it is practically difficult to increase the physical and cost.

In view of the above, the present applicant has disclosed Japanese Patent Application No. 5-71942, which aims at realizing a device capable of performing a lane departure warning of a vehicle even at night.
In this, the main headlamp of the vehicle is modified to have a means for leaking a part of the irradiation beam and irradiating the area immediately before the vehicle photographed by the lane detecting means.

That is, when the main headlight of the vehicle is turned on during night driving, the irradiation beam of the main headlight illuminates a distant road surface ahead of the vehicle. In this case, the illuminated road surface is a lane detecting means. Is different from the road surface position due to the immediately preceding visual field to be detected.

Therefore, the main headlamp is provided with a means for changing the irradiation direction of a part of the irradiation beam, and this means generates a leaky beam from the irradiation beam so that the lane detecting means immediately before the vehicle will take an image. And illuminates the road surface with respect to the visual field to output an image signal.

[0011]

However, the prior art disclosed in Japanese Patent Application No. 5-71942 has the following problems. (1) If the main headlight is installed at a position retracted from the front end of the bumper due to the design of the vehicle, the field of view of the lane detecting means will be the shadow of the bumper when viewed from the main headlight. The leakage beam of the headlight cannot illuminate the entire field of view of the lane detecting means.

(2) The glass lens portion of the main headlight is formed by a mold. However, when a main headlight common to various derivative vehicle types such as a commercial vehicle is diverted, the vehicle height and the mounting dimensions are different. It is difficult to form the best leakage beam with a common glass lens shape for each different car model.

(3) In the case of the above (2), it is not realistic to set a glass lens type for each derivative vehicle type and to cope with it, since the investment in the type is high.

(4) Further, when the lane departure warning device is retrofitted to a vehicle already on the market and not equipped with the lane departure warning device used by the user, it is assumed that the lane departure warning device is mounted. Unlike the case of a designed and manufactured vehicle, it is necessary to deal with each vehicle such that a leak beam is formed in the main headlight, and the versatility of the lane departure warning device is reduced.

Therefore, according to the present invention, a lane on a road surface is extracted from an image signal obtained from a lane detecting means for photographing immediately before a vehicle, and when the distance between the lane and the vehicle is smaller than a predetermined value, a direction indication is made. An object of the present invention is to provide a lane departure warning device that issues a warning if the operation is not performed, even at night without modifying a main headlight of the vehicle.

[0016]

In order to achieve the above-mentioned object, a lane departure warning system according to the present invention is constructed as shown in FIG.
As shown in principle in (1) and (2), the main headlight 2 of the vehicle 10 is installed on the vehicle 10 so that the road surface immediately before the vehicle 10 photographed by the lane detecting means 1 can be irradiated. An auxiliary lighting lamp 2 that emits invisible light B in conjunction with lighting ;
Means for detecting the invisible light, and means for detecting the invisible light.
If not, an alarm is issued as a failure of the auxiliary lighting 2
And a circuit which is provided.

The auxiliary illumination lamp 2 can emit ultraviolet light or infrared light as the invisible light.

[0018]

[0019]

According to the present invention, an invisible ultraviolet (UV) ray or an infrared (IR) ray is emitted from the auxiliary lighting lamp 2 as an irradiation beam B from the front of the vehicle 10 toward the road surface (FIG. 1 (1) )
reference).

The invisible light is transmitted to the main headlight 2 of the vehicle 10.
Turns on / off in conjunction with the lane detection means 1
The vehicle 10 is installed on the vehicle 10 so that the road surface immediately before the vehicle 10 can be illuminated (see FIG. 1 (2)).

Therefore, such invisible light is reflected by the lane and is given to the lane detecting means 1.

In this case, the lane detecting means 1 detects the lane as follows using the ultraviolet / infrared light as invisible light.

In the case of an ultraviolet lamp: Ultraviolet light has an ultraviolet fluorescent action, and excites elements and molecules in a white pigment used for lane paint to emit visible light. Therefore, visible light is emitted from the lane paint part by the irradiation of ultraviolet rays, and can be detected by the lane detection sensor.

In the case of an infrared lamp: Since a CCD element generally used for the lane detecting means 1 has sensitivity not only in the visible light region but also in the infrared light region as a general characteristic, infrared light is
As in the case of the visible light, the light is reflected by the lane paint portion on the road surface, reaches the lane detecting means 1, and its presence can be detected.

Then, the lane is extracted in the same manner as in the prior art.
When the distance between the lane and the vehicle becomes equal to or less than a predetermined value, an alarm is issued unless the direction instruction operation is performed.

However, the invisible light is different from the visible light, and its lighting condition cannot be confirmed with the naked eye, and it hinders the inspection and maintenance of the ultraviolet light from the auxiliary lighting lamp 2 or the infrared lamp. A light detection unit is provided to monitor the lighting state of the auxiliary lighting lamp 2.

When the auxiliary lighting lamp 2 is to be turned on and the lighting is not confirmed by the light detecting means, it is determined that the auxiliary lighting lamp 2 has failed, and a failure alarm is notified to the driver.

[0028]

FIG. 2 shows the lane departure warning device according to the present invention shown in FIG. 1 more specifically. FIG. 2 shows the arrangement when the lane departure warning device according to the present invention is actually mounted on a vehicle 10. Is shown.

In FIG. 2, a line camera 1 as a lane detecting means is installed on a roof in front of a vehicle 10 to detect a road surface based on a detection field of view C. The illumination lamp 2 illuminates the front of the road surface with the irradiation beam A. Therefore, the detection visual field C has no area on the road surface that coincides with the irradiation beam A.

An auxiliary illumination lamp 3 for emitting ultraviolet light or infrared light as invisible light is attached to, for example, a bumper BP of the vehicle 10 and outputs an irradiation beam B to a road surface.

In order to detect an operation failure of the auxiliary lighting lamp 3, that is, to detect reflected light of ultraviolet or infrared rays from the auxiliary lighting lamp 3 from a road surface, a light detection sensor also serves as the invisible light detecting means. 4 is attached to the bumper BP.

The light detecting sensor 4 is connected to a monitoring circuit 5, and the monitoring circuit 5 is further connected to a warning lamp 6 for issuing a failure alarm. The warning lamp 6 is installed, for example, in a driver's seat so that the driver can see it.

A controller 7 equipped with a CPU as a signal processing means is provided, for example, below the driver's seat and receives an output signal from the line camera 1 and receives signals from a vehicle speed sensor and a direction indicator (not shown). An output signal is also input at the same time.

An alarm device 8 for giving a lane departure alarm to a driver includes an actuator driving circuit 81 driven by the controller 7 and a steering actuator 82 driven by the driving circuit 81. The actuator 82 gives an alarm to the driver by vibrating the steering 83 when an alarm is generated.

FIG. 3 shows an electrical diagram of the lane departure warning device according to the present invention shown in FIG.
The key switch (SW) 12 and the lamp switch (S
W) 13 is connected, and the lamp switch 13 is further connected to a vehicle width light 14, a dimmer switch (SW) 15, an auxiliary illumination light 3, a light detection sensor 4, and a monitoring circuit 5.

The dimmer switch 15 is connected to a left headlight 21 and a right headlight 22 constituting the main headlight 2, and switches the front illumination direction up and down according to its H position or L position. Like that.

The light detection sensor 4 is composed of a left light detection sensor 41 and a right light detection sensor 42, and has filters 41a and 42a, respectively, that transmit only desired light out of ultraviolet rays or infrared rays. , And outputs a voltage proportional to the amount of incident target light. Each output signal of these sensors 41 and 42 is given to a monitoring circuit 5, and a warning lamp 6 is connected between the monitoring circuit 5 and the key switch 12.

The above-mentioned components, except for the auxiliary illumination light 3, the light detection sensor 4, the monitoring circuit 5, and the warning lamp 6, are well-known components provided in a normal vehicle and include a main headlight. 2 includes a left headlight 21 and a right headlight 22.

Next, the operation of FIG. 3 will be described.
The power supply B11 is connected to the lamp switch 13, and the key switch 12 is closed to supply the power supply V of the battery 11 to a vehicle electric circuit (not shown) other than the electric circuit system.
Supply B.

In this state, the driver operates the lamp switch 1
When the switch 3 is switched from the "OFF" state to, for example, the "SMALL" state, battery power is supplied only from the lamp switch 13 to the vehicle width light 14, and the vehicle width light 14 is turned on. .

When the driver further switches the lamp switch 13 to the "H / L" state, the dimmer switch 15, the left and right auxiliary illumination lights 31, 32, and the left and right light detection sensors 4
Battery power is also connected to the monitoring circuits 5 and 1,42. Then, the illumination direction of the main headlight 2 is switched according to the position of the dimmer switch 15.

As described above, the main headlight 2 is turned on by operating the lamp switch 13 and the auxiliary light 3 is turned on in conjunction with the operation.

Therefore, as described above with reference to FIG. 1, when ultraviolet light or infrared light from the auxiliary illumination lamp 3 is applied to the road surface, visible light is reflected by the lane on the road surface and the line camera 1
The controller 7 receives the output image signal from the line camera 1 and determines lane departure.
When it is determined that the vehicle is deviating from the lane, the steering actuator 8
2 to alert the driver by vibrating the steering 83.

When the auxiliary illumination lamp 3 is turned on, the light detection sensor 4 gives its output signal to the monitoring circuit 5, so that the monitoring circuit 5 does not turn on the warning lamp 6 assuming that the auxiliary illumination lamp 3 is operating normally. .

However, if the auxiliary illumination lamp 3 fails, the above-mentioned alarm operation cannot be given correctly and it is dangerous. Therefore, the output signals of the light detection sensors 41 and 42 indicate that the monitoring circuit 5 is in a failure state. Thus, the warning lamp 6 is turned on to give an alarm to the driver.

FIG. 4 shows an embodiment of such a monitoring circuit 5. In this embodiment, the light detection sensors 41 and 42 are used.
5 each having an inverting input terminal connected to
1, 52, an OR gate 53 for inputting the output signals of the comparators 51, 52, and an AND gate 56 for inputting the output signal of the OR gate 53 and the output signal of the constant voltage source 55 connected to the power supply 54. And the warning lamp 6 driven by the output signal of the AND gate 56.
And an output transistor 57 for turning on. Note that always the reference voltage V _{RE F} is given to the non-inverting input terminal of the comparator 51.

In the operation of the monitoring circuit 5, the outputs of the light detection sensors 41 and 42 are constantly output from the comparators 51 and 5.
2 and are compared with a reference voltage V _REF .

In this case, the lamp switch 13 is set to "H /
When the state is switched to the “L” state, the auxiliary lighting 31
In the case where 32 is not lit, the comparators 51 and 5
The output voltage from the light sensor 41 to the second inverting input terminal, reference the voltage V _REF becomes lower than, the auxiliary lamp 31 is turned off to have the determination to output of the voltage level "H" Generate a signal.

The output signals of the comparators 51 and 52 are applied to an AND gate 56 via an OR gate 53. If the output voltage of the constant voltage source 55 exists, that is, the auxiliary illumination lamps 31 and 32 are turned on. If it is in a state that should be
Since the AND gate 56 is enabled,
The output signal of the R gate 53 is used as is in the output transistor 5
7 to turn on the warning lamp 6.

When the auxiliary lamps 31 and 32 are normally lit, the output voltage from the light detection sensors 41 and 42 to the inverting input terminals of the comparators 51 and 52 is higher than the reference voltage _VREF. Therefore, the comparators 51 and 5
2 becomes "L" level, and the output transistor 57 and the warning lamp 6 are not driven.

[0051]

As described above, according to the lane departure warning device of the present invention, the main headlight of the vehicle is installed on the vehicle so that the road surface immediately before the vehicle photographed by the lane detecting means can be irradiated. An auxiliary light that emits invisible light in conjunction with the lighting of the light, and an auxiliary light that emits invisible light when the invisible light is not detected.
Since a circuit for issuing a warning as a failure of the auxiliary lighting is provided, the lane departure warning function at night can be normally secured without violating the vehicle security standards regarding lights.

Further, since the lane departure warning function can be ensured regardless of the presence or absence of the leak beam of the existing main headlight, the lane departure warning device can be easily applied to vehicles having different specifications. Thus, the versatility of the alarm device can be improved.

[0053]

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of a lane departure warning device according to the present invention.

FIG. 2 is a schematic configuration diagram when the lane departure warning device according to the present invention is incorporated in an actual vehicle.

FIG. 3 is a circuit diagram showing an electric system used in the lane departure warning device according to the present invention.

FIG. 4 is a diagram showing an embodiment of a monitoring circuit used in the lane departure warning device according to the present invention.

FIG. 5 is a schematic diagram for explaining a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lane detecting means 2 (21, 22) Main headlight 3 (31, 32) Auxiliary light 4 (41, 42) Light detection sensor 5 Monitoring circuit 6 Fault warning lamp 7 Controller 8 (81, 82) Alarm device 10 Vehicle A Main headlight irradiation beam B Auxiliary lamp irradiation beam C Detection visual field In the drawings, the same reference numerals indicate the same or corresponding parts.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) G08G 1/00-9/02 B60Q 1/00 B60R 21/00 G08B 21/00

Claims (2)

(57) [Claims] 1. A lane on a road surface is extracted from an image signal obtained from a lane detecting means for photographing immediately before a vehicle, and when a distance between the lane and the vehicle is smaller than a predetermined value, a direction instruction operation is performed. A lane departure warning device that issues an alarm if it is not set, is installed in the vehicle so that the road surface immediately before the vehicle captured by the lane detecting means can be illuminated, and is invisible in conjunction with turning on of a main headlight of the vehicle. An auxiliary light emitting a light beam ;
Means for detecting visible light; and means for detecting the invisible light.
A circuit that issues an alarm when the auxiliary lighting fails
And a lane departure warning device. 2. The lane departure warning device according to claim 1, wherein the auxiliary lighting emits one of ultraviolet light and infrared light as the invisible light.