JPH06275104A - Vehicle headlamp device - Google Patents

Abstract

PURPOSE:To surely prevent casting glare to other vehicles by estimating the distance between vehicles according to the distance to one vehicle detected from an image signal and to the relative velocities of the vehicles, and controlling a headlamp based on the distance between the vehicles. CONSTITUTION:The situation in front of a vehicle is photographed for every predetermined period T. Another vehicle is detected according to an image signal obtained by the photographing, so as to detect the distance to this vehicle and the relative velocities of the vehicles. The distance between the vehicles is estimated from these detected values and for a period Tn shorter than the period T. At least either the direction or range of illumination of a headlamp is controlled based on the estimated distance between the vehicles. Therefore, even if it takes time to measure the distance and relative velocities between the vehicles, the effect of this is eliminated, and casting glare to other vehicles can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular headlamp device, and more particularly to a vehicular headlamp device having a headlamp capable of changing at least one of an irradiation direction and an irradiation range.

[0002]

2. Description of the Related Art In a vehicle, a pair of headlamps are provided on the right and left sides of the front end of the vehicle. The headlamps are turned on when it is difficult to visually recognize the situation ahead, such as at night, and the driver can see the front of the vehicle. It is designed to improve sex. This headlamp generally has a configuration in which the irradiation range can be switched to only two stages of high beam and low beam, and when another vehicle such as a preceding vehicle or an oncoming vehicle is present, the driver of the other vehicle can be changed. The low beam is often chosen so as not to give dazzling and unpleasant glare. However, for example, when the inter-vehicle distance with another vehicle is long, in the low beam, the driver continuously looks at the dark part outside the irradiation range of the headlamp, and in the high beam, glare is given to the other vehicle. There is a problem that it is difficult to always irradiate an appropriate area in front.

For this reason, a light-shielding plate for shielding the irradiation light is provided inside the headlamp, and the light-shielding plate is moved so that a sufficient irradiation range can be obtained without giving glare to other vehicles. The boundary between the area and the unirradiated area (hereinafter,
It has been proposed to control the position of this boundary). Further, as a technique for controlling the position of the cut line so as not to give glare to other vehicles, a situation in front of the vehicle is imaged by a CCD camera or the like, and the preceding vehicle is recognized based on an image signal output from the CCD camera. It has been proposed to detect the inter-vehicle distance to the preceding vehicle and control the light distribution of the headlamps according to the inter-vehicle distance (Japanese Patent Laid-Open No. 6-58242).
2-131837).

[0004]

However, there is a problem that it takes time to recognize another vehicle based on the above-mentioned image signal. For example, in order to recognize one preceding vehicle, it is necessary to detect a white line representing the lane in which the own vehicle is traveling in the image, and perform processing for recognizing a vehicle traveling in the next lane as the preceding vehicle. At present, only this process
It takes about 100 milliseconds. Further, this time further increases as the number of areas (lanes) for recognizing vehicles increases or the number of vehicles for recognizing increases, and it takes 500 mm to 1 second as a whole.

On the other hand, the distance between the preceding vehicle and the oncoming vehicle changes while the vehicle is being recognized. Therefore, even if the light distribution is changed so as not to give glare to other vehicles based on the result of recognizing the other vehicle and detecting the inter-vehicle distance, the inter-vehicle distance until the next inter-vehicle distance detection result is output. A change in distance may give glare to other vehicles. In particular, since the relative speed difference with the oncoming vehicle is large, the distance between the oncoming vehicle and the oncoming vehicle changes greatly while recognizing the other vehicle and detecting the intervehicular distance, and it is very likely that the oncoming vehicle will have glare. .

The present invention has been made in view of the above facts, and an object thereof is to obtain a vehicle headlight device which can prevent glare from being applied to other vehicles.

[0007]

In order to achieve the above object, a vehicle headlamp device according to the present invention comprises a headlamp capable of changing at least one of an irradiation direction and an irradiation range, and at a predetermined cycle, The other vehicle is detected based on an image signal obtained by capturing the situation in front of the vehicle, the inter-vehicle distance between the own vehicle and the detected other vehicle is detected, and the irradiation direction of the headlamp is detected based on the detected inter-vehicle distance. And a vehicle headlamp device for controlling at least one of an irradiation range, detecting a relative speed with the other vehicle together with the inter-vehicle distance, in a cycle shorter than the detection cycle of the other vehicle, the cycle and the Estimating the current inter-vehicle distance to the other vehicle based on the inter-vehicle distance and the relative speed, and controlling at least one of the irradiation direction and the irradiation range of the headlamp based on the estimated inter-vehicle distance, That.

[0008]

According to the present invention, the other vehicle is detected every predetermined period based on the image signal obtained by picking up the situation in front of the vehicle, and the inter-vehicle distance between the own vehicle and the detected other vehicle is detected. Detects the relative speed with the vehicle. The relative velocity can be detected using, for example, a millimeter wave radar. This millimeter wave radar is a radar that uses the Doppler effect,
It is possible to detect the inter-vehicle distance and the relative speed at the same time. Further, based on a laser radar or an image representing the situation in front of the vehicle, the inter-vehicle distance to the other vehicle is detected, and the relative speed to the other vehicle is calculated by calculation based on the change in the measured inter-vehicle distance. May be.

Further, the present invention estimates the current inter-vehicle distance with another vehicle based on the period, the inter-vehicle distance, and the relative speed in a cycle shorter than the detection cycle, and the headlamp based on the estimated inter-vehicle distance. At least one of the irradiation direction and the irradiation range of is controlled. The estimation of the inter-vehicle distance, for example, based on the cycle, obtains the elapsed time from the time of detecting the inter-vehicle distance and the relative speed, assuming that the relative speed with other vehicles is constant, as a change in the inter-vehicle distance. It can be obtained by calculating the product of the elapsed time and the relative speed and correcting the inter-vehicle distance by the calculation result.

The inter-vehicle distance may be estimated based on the inter-vehicle distance estimated last time, the cycle (elapsed time from the previous time) and the relative speed. The estimation of the inter-vehicle distance is not limited to the assumption that the relative speed is constant, but the inter-vehicle distance estimated by detecting the degree of change in the relative speed and assuming that the relative speed is constant. May be further modified according to the degree of change in the relative speed.

By the way, as described above, since it takes time to detect another vehicle based on the image signal obtained by imaging the situation in front of the vehicle, the detection of the other vehicle and the distance between the detected other vehicle and the other vehicle are detected. Even if the distance and the relative speed are repeatedly detected, it is difficult to sequentially output the detection results of the inter-vehicle distance and the relative speed in a short cycle. Therefore, the inter-vehicle distance may change significantly during the period.

However, according to the present invention, the irradiation direction and the irradiation range of the headlamp are periodically controlled, and the current inter-vehicle distance with another vehicle is estimated based on the cycle and the inter-vehicle distance and the relative speed. Since it is performed based on the inter-vehicle distance, even if time has elapsed from the time of detecting the inter-vehicle distance and the relative speed when performing the control, the irradiation direction and the irradiation range of the irradiation direction and the irradiation range are adjusted so as not to give glare to other vehicles. It is possible to control at least one of them. Therefore,
The light distribution control of the headlamp can be performed more finely in a cycle shorter than the detection cycle of the other vehicle without being restricted by the processing time required for detecting the other vehicle and the inter-vehicle distance and the relative speed. Therefore, even if it takes a long time to perform processing such as detection of another vehicle, this effect can be eliminated and glare can be prevented from being given to another vehicle.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings. As shown in FIG. 1, an engine hood 12 is arranged on an upper surface portion of a front body 10A of a vehicle 10, and a front bumper 16 is provided at a front end portion of the front body 10A from once in the vehicle width direction to the other end. Is fixed. This front bumper 16 and engine hood 1
A pair of headlamps 18 and 20 are disposed between the two front edge portions at both ends in the vehicle width direction.

A windshield glass 14 is provided in the vicinity of the rear end of the engine hood 12, so that the vehicle 10
A room mirror 15 is provided in the vicinity of a portion corresponding to the upper side of the windshield glass 14 inside. A TV camera 22 for picking up an image of the situation in front of the vehicle is arranged near the rear-view mirror 15. TV camera 22
Is connected to the image processing device 48 (see FIG. 4). In the present embodiment, as the TV camera 22, a TV camera that includes a CCD element that simply detects only the amount of light and that outputs an image signal representing a monochrome image is used.

The TV camera 22 is arranged at a position as close as possible to the driver's viewpoint position (so-called eye point) so that the road shape in front of the vehicle can be accurately recognized and the driver's visual sense is matched. It is preferably arranged. Further, the road shape in the present embodiment includes the shape of the traveling road, for example, the road shape corresponding to one lane formed by the center line, the curb, or the like.
Further, a speedometer (not shown) is arranged on the vehicle 10, and a vehicle speed sensor 66 (FIG. 4) for detecting the vehicle speed V of the vehicle 10 is provided on a cable of the speedometer (not shown).
Are installed). The vehicle speed sensor 66 is connected to the image processing device 48 and outputs the detection result of the vehicle speed V.

A radar 80 as a measuring means is arranged inside the front grill of the vehicle 10. In this embodiment, as the radar 80, a millimeter-wave radar is used in which the width of the detection area is about the size of one lane through which the vehicle travels. Further, the radar 80 employs a so-called FMCW radar system which can measure a distance and also detect a relative speed from a beat signal of a triangular wave. The radar 80 has
An actuator 82 (see FIG. 4) for rotating the radar 80 in the arrow A direction and the arrow B direction in FIG. 1 is connected.

The radar 80 is rotated by the actuator 82 in the arrow A direction or the arrow B direction in FIG. 1 so that other vehicles existing in the respective directions in front of the vehicle 10 are accommodated within the detection area, and The distance between vehicles and the relative speed can be measured. The radar 80 is the control device 50.
Is connected to the input port 58 (see FIG. 4) of the vehicle and outputs the result of measuring the inter-vehicle distance and the relative speed to the control device 50. The actuator 82 is connected to the output port 64 of the control device 50, and is configured to rotate the radar 80 in the arrow A direction or the arrow B direction by the rotation angle designated by the control device 50.

As shown in FIGS. 2 and 3, the headlamp 18 is a projector-type headlamp and includes a convex lens 30, a bulb 32 and a lamp house 34.
The lamp house 34 is fixed substantially horizontally to a frame (not shown) of the vehicle 10. A convex lens 30 is fixed to one opening of the lamp house 34, and an optical axis L of the convex lens 30 (of the convex lens 30) is fixed to the other opening. The bulb 32 is fixed via a socket 36 so that the light emitting point is located on the central axis).

On the bulb side inside the lamp house 34, a reflector 38 having an elliptical reflection surface is formed.
The light emitted from 8 is reflected by the reflector 38 and condensed between the convex lens 30 and the bulb 32. An actuator 40 is arranged near this condensing point. The actuator 40 includes a light-shielding cam 40A that is rotatably supported by a rotary shaft 44 that is fixed in the lamp house 34 along the vehicle width direction.
A gear 40B is fixed to the. A gear 40C fixed to the drive shaft of the motor 40D meshes with the gear 40B. The motor 40D is connected to the driver 64 of the control device 50.

The bulb 3 reflected and condensed by the reflector 38
The second light is blocked by the light blocking cam 40A of the actuator 40, and the other light is emitted from the convex lens 30. The light-shielding cam 40A has a cam shape in which the distance from the rotation shaft 44 to the outer circumference continuously changes along the circumferential direction, and is rotated by driving the motor 40D in response to a signal from the control device 50. Be moved. This shading cam 40A
With the rotation of, the position of the boundary where the light of the bulb 32 is divided into the passing light and the blocked light changes up and down. This boundary appears as a cut line (cut line 70 shown in FIG. 9) which is a light / dark boundary in the light distribution in front of the vehicle 10.

As shown in FIG. 9, the position of the cut line 70 corresponds to the uppermost position by turning the light-shielding cam 40A (the position shown by the solid line as the cut line 70 in FIG. 9, the so-called high beam or less). Position) to a position corresponding to the lowest position (position indicated by imaginary line in FIG. 9, so-called low beam level position). Also, headlamp 2
Since 0 has the same configuration as the headlamp 18, a detailed description thereof will be omitted, but as shown in FIG.
1 is attached. The actuator 41 includes a light shielding cam 41A (not shown), and the position of the cut line is moved as the light shielding cam 41A rotates.

As shown in FIG. 4, the control device 50 has a read-only memory (ROM) 52, a random access memory (RAM) 54, a central processing unit (CPU) 56, an input port 58, an output port 60, and these connected. It is configured to include a bus 62 such as a data bus and a control bus. The ROM 52 stores a map and a control program described later.

A vehicle speed sensor 66 and an image processing device 48 are connected to the input port 58. This image processing device 4
Reference numeral 8 denotes a TV camera 22 and a control device 50 as described later.
The image captured by the TV camera 22 is image-processed based on the signal input from the. The output port 60 is connected to the actuators 40 and 42 of the headlamp 18 and the actuator 4 of the headlamp 20 via the driver 64.
1 and 43 are connected. Also, the output port 60 is
It is also connected to the image processing device 48.

Next, the operation of this embodiment will be described with reference to the flow charts of FIGS. Driver is vehicle 1
When the light switch 0 (not shown) is turned on to turn on the headlamps 18 and 20, the inter-vehicle distance / relative speed measurement routine shown in FIG. 5 is executed at predetermined intervals T. In step 200 of the inter-vehicle distance / relative speed measurement routine, the preceding vehicle recognition process is executed, and the preceding vehicle traveling ahead of the host vehicle 10 is recognized. The preceding vehicle recognition processing will be described with reference to the flowchart of FIG.

In FIG. 10A, the vehicle 10 is on the road 122.
An example of an image (image 120) that is substantially coincident with the image visually recognized by the driver, which is captured by the TV camera 22 while traveling on the road, is shown. This road 12
The vehicle 2 has white lines 124 on both sides of the lane in which the vehicle 10 travels. The position of each pixel on the image is specified by the coordinates (X _n , Y _n ) of the coordinate system defined by the X axis and the Y axis which are set on the image and are orthogonal to each other. In the following, other vehicles including the preceding vehicle are recognized based on this image.

In step 300 of the flowchart of FIG. 7, an area having a predetermined width γ on the image is set as the white line detection window area W _sd as shown in FIG. In the present embodiment, considering that only an image of approximately 40 to 50 m in front of the vehicle 10 can be detected when the vehicle 10 is traveling at night, the white line above 60 m in front of the vehicle 10 is not detected. In addition, the lower area in the image is less likely to have a preceding vehicle. Therefore, the white line detection window area W _sd
In order to be able to detect up to 60 m in front of the vehicle 10, a white line detection window region W _sd is set by removing a region above the predetermined horizontal line 140 and a region below the lower limit line 130.

In the next step 302, the window area W _sd
The inside is differentiated with respect to the brightness, and the peak point (maximum point) of this differential value is extracted as the edge point which is the white line candidate point. That is, in the window region W _sd in the vertical direction (arrow A in FIG.
Direction), the brightness of each pixel in the horizontal direction from the pixel at the lowermost position to the pixel at the uppermost position is differentiated, and the peak point of the differential value having a large fluctuation in brightness is extracted as the edge point. Thus, as an example, the window area W _sd of FIG.
Continuous edge points are extracted as indicated by a broken line 132 in the figure.

In step 304, a linear approximation process is performed.
In this processing, the edge points extracted by the white line candidate point extraction processing are linearly approximated using Hough transform, and approximate straight lines 142 and 144 along the line estimated to be the white line are obtained. In the next step 305, the intersection point P _N (X
The coordinate value = X _N ) is obtained, and the horizontal displacement amount A (A) between the obtained intersection point P _N and the intersection point P ₀ (X coordinate value = X ₀ ) of the approximate straight line in the case of a predetermined straight line as a reference. = X _N −X ₀ ). The displacement amount A corresponds to the degree of the curve of the road 122.

In the next step 306, the displacement amount A is A ₂
Road 1 by determining whether the ≧ A range of ≧ A ₁
It is determined whether 22 is a substantially straight road. This judgment reference value A ₁
Is a reference value representing the boundary between a straight road and a right curve road,
The judgment reference value A ₂ is a reference value representing the boundary between the straight road and the left curved road. When it is determined that the road is a straight road in step 306, the vehicle speed V of the host vehicle 10 is read in step 308.

In the next step 310, in setting the preceding vehicle recognition area W _P for recognizing the preceding vehicle according to the read vehicle speed V, the correction width α for correcting the position of the approximate straight line is set.
Determine _L and α _R. When traveling at high speeds, the radius of curvature of the road on which the vehicle can turn is large, so it can be considered that the vehicle is traveling on a substantially straight road. Even if the road is close to the vehicle, if the radius of curvature of the road is small in the distance, the vehicle may deviate from the preceding vehicle recognition area W _P.
Therefore, the correction widths α _L and α _R are set so that the values increase as the speed V decreases, using the map shown in FIG.

At the next step 312, the lower limit line 130,
An approximate straight line 142 whose position is corrected by the correction widths α _L and α _R ,
The area surrounded by 144 is set as the preceding vehicle recognition area W _P (see FIG. 12). Note that the area of the preceding vehicle recognition area W _P is also increased as the vehicle travels at a lower speed as the correction widths α _L and α _R are changed according to changes in the vehicle speed V (see FIG. 13).

On the other hand, if the determination in step 306 is negative, it is determined in step 314 whether A> A _{2 and} whether the road is a right curve road or a left curve road. If the determination is affirmative, the road is determined to be a right curve road, the vehicle speed V of the vehicle 10 is read in step 316, and the correction widths α _L , α corresponding to the read vehicle speed V are used by using the map shown in FIG. Correction value for _R α _L ', α _R '
Is determined in step 318. In the next step 320, the gains GL for determining the correction widths α _R , α _L of the left and right approximate straight lines according to the displacement amount A indicating the degree of the curve,
GR is determined using the maps shown in FIGS. 15 and 16,
In step 322, the left and right correction widths α _R and α _L of the final window region are determined based on the determined correction values α _R ′ and α _L ′ and the gains GL and GR.

At this time, since the road is a curved road, the left and right are asymmetrical, and the approximate straight lines 142 and 144 have different slopes. Therefore, the left and right correction widths α _R and α _L are set to independent values. That is, when the road is a right-curved road and the radius of curvature is small (the displacement amount A is large), the probability that the preceding vehicle is present on the right side is high. Therefore, the correction width α _R is increased by increasing the gain GR on the right side (see FIG. 15).
In addition, the correction width α is reduced by reducing the gain GL on the left side.
_{Reduce L} (see FIG. 16). Further, when the road is a right curved road and the radius of curvature is large (the displacement amount A is small), the correction width α _R is reduced by decreasing the gain GR on the right side, and the correction is performed by increasing the gain GL on the left side. Increase the width α _L. This change in the correction width is shown as an image in FIG.

In step 324, the determined correction width α
_The area surrounded by the approximate straight lines 142 and 144 whose positions are corrected by _L and α _R is set as the preceding vehicle recognition area W _P.

On the other hand, if the determination in step 314 is affirmative, it is determined that the road is a left curved road, and step 3
26, and the vehicle speed V of the vehicle 10 is read. In step 328, the read vehicle speed V is read using the map of FIG.
The left and right correction values α _R ′, α _L ′ are determined in accordance with the above, and in step 330 the left and right gains GL, GR corresponding to the displacement amount A are determined. That is, when the road is a left curved road and the radius of curvature is small (the displacement amount A is large), it is highly likely that the preceding vehicle is on the left side. Therefore, the correction width can be reduced by reducing the gain GR on the right side according to the map shown in FIG. The correction width α _L is increased by decreasing α _R and increasing the gain GL on the left side according to the map shown in FIG.

In the next step 332, the left and right correction widths α _R and α _L of the final window region are determined based on the determined correction values α _R 'and α _L ' and the gains GL and GR,
In step 334, the left and right correction widths α _R and α _{L determined}
The area surrounded by the approximate straight lines 142 and 144 whose position is corrected by is set as the preceding vehicle recognition area W _P. When the preceding vehicle recognition area W _P is set as described above, the process proceeds to step 336.

In step 336, horizontal edge detection processing in the preceding vehicle recognition area W _P is performed as the preceding vehicle recognition processing. This horizontal edge detection process is performed in step 3 first.
Similar to the edge detection process of 02, detection of horizontal edge points is performed within the vehicle recognition area W _P. Next, the detected horizontal edge points are laterally integrated to detect a peak point E _P at a position where the integrated value exceeds a predetermined value (see FIG. 10B).
This horizontal edge is likely to appear when a preceding vehicle is present.

In the next step 338, the position coordinates of the preceding vehicle are calculated. First, vertical edge detection processing is performed. When the peak point E _P of the integrated value of the horizontal edge points are multiple, the peak point E _P located below on the image in order, the peak point E _P
The window regions W _R and W _L for detecting the vertical lines are set so as to include both ends of the horizontal edge points included in (see FIG. 10C). Vertical edges are detected in the window regions W _R and W _L , and vertical lines 138R and 138 are detected.
When L is stably detected, window regions W _R and W _L
It is determined that the preceding vehicle exists in the area sandwiched by.

Next, the vehicle width is obtained by obtaining the lateral distance between the vertical lines 138R and 138L detected in each of the window regions W _R and W _L , and the vehicle width is obtained as the coordinates of the position of the vehicle on the image. Find the coordinates of the center. The preceding vehicle recognition process is completed as described above, and the process proceeds to step 202 of the inter-vehicle distance / relative speed measurement routine shown in FIG.

At step 202, oncoming vehicle recognition processing is performed.
U Regarding this oncoming vehicle recognition processing, the flowchart of FIG.
It will be described with reference to FIG. In step 404, the
Intersection point P of the approximate straight line obtained in the traveling vehicle recognition area setting process_N
And the intersection point P of the approximate straight line in the case of the reference straight road₀When,
Read the horizontal displacement A (see step 305)
It In the next step 406, the displacement amount A is A₂≧ A ≧ A
₁Within the range of, and if the determination is affirmative
The road 122 is determined to be a substantially straight road, and the vehicle is determined in step 408.
The vehicle speed V of 10 is read, and the next step 410 reads it.
Oncoming vehicle recognition area W according to the vehicle speed V_POTo set
Correction width α for correcting the position of the approximate straight line of_RODetermine
It This correction width α_ROIs the preceding vehicle recognition area W_PTo
Α _R, Α_LSimilarly, use the map shown in Fig. 20.
The correction range is large when driving at low speeds and small when driving at high speeds.
To get rid of In the next step 412, the lower limit line 130, the approximation
Straight line 144 and determined correction width α_ROOncoming vehicle
Oncoming vehicle recognition area W for recognizing both_POTo decide
(See Figure 21).

On the other hand, when the determination in step 406 is negative, it is determined in step 414 whether the displacement amount A is A> A ₂ . If the determination in step 414 is affirmative, it is determined that the road is a right curve road, the vehicle speed V of the vehicle 10 is read in step 416, and the next step 418 is
Correction value α for the correction width α _RO according to the read vehicle speed V
_RO 'is determined using the map in FIG. In the next step 420, to determine the gain GR _O for determining the correction width alpha _RO by using the map shown in FIG. 22, step 422
, The determined correction value α _RO 'and the gain GR _O
The correction width α _RO for correcting the position of the approximate straight line 144 is determined based on In step 424, the oncoming vehicle recognition area W _PO for recognizing the oncoming vehicle is determined using the determined correction width α _RO .

On the other hand, the judgment in step 414 is denied.
If the road is a right turn, step
The process proceeds to 426, and the vehicle speed V of the vehicle 10 is read. Next step
At step 428, the read vehicle speed V and the map of FIG.
Based on the correction value α_RO', And in step 430
Gain GR according to unit A_OThe map shown in Figure 23 is used
Decide. In step 432, the determined correction value
α_RO'And gain GR _OFinal correction width α based on_RO
And the correction width α determined in the next step 434.
_ROUsing the preceding vehicle recognition area W_POTo decide.

When the oncoming vehicle recognition area W _PO is determined as described above, the process proceeds to step 436, and the horizontal edge point integration is performed in the determined oncoming vehicle recognition area W _PO as in the preceding vehicle recognition processing described above. The oncoming vehicle is recognized by performing. In step 438, the oncoming vehicle recognition window area W _OO is further added to the oncoming vehicle recognition area W _PO so as to include the integration peak point of the horizontal edge point (see FIG. 21), and the edge points are integrated in the vertical direction to obtain an image on the image. Obtain vehicle position coordinates.

The processing from the next step 440 is performed on all the vehicles detected by the preceding vehicle recognition processing and the oncoming vehicle recognition processing. That is, in step 440, it is determined which of the preceding vehicle recognition area W _P and the oncoming vehicle recognition area W _PO the calculated vehicle position (X-axis coordinate) is included in.
If it is included in the oncoming vehicle recognition area W _PO , step 44.
The determination of 0 is affirmative, and the vehicle is recognized as an oncoming vehicle in step 448. On the other hand, if the vehicle position (X-axis coordinate) is included in the preceding vehicle recognition area W _P , the determination at step 440 is negative, and at step 442 it is determined whether the horizontal edge integration amount exceeds the predetermined value β. judge.

When the horizontal edge integration amount exceeds the predetermined value β, the determination at step 442 is affirmative and the routine proceeds to step 446, where the vehicle is recognized as an oncoming vehicle,
The vehicle recognized as the preceding vehicle is corrected to the oncoming vehicle. Since the oncoming vehicle emits the light of the headlamp toward the own vehicle, the brightness (integral value of the edge point) detected as a vehicle in front of the oncoming vehicle is more than that of the reflected light of the preceding vehicle or the direct light of the tail lamp. The light of the oncoming vehicle, which is the direct light from the headlamp, becomes brighter. Therefore, the preceding vehicle and the oncoming vehicle can be discriminated by setting the predetermined value β to a value corresponding to the light from the headlamp. On the other hand, the horizontal edge integration amount is a predetermined value β
In the following cases, the vehicle is recognized as the preceding vehicle in step 444. This processing is performed for all the recognized vehicles, and this routine is ended.

As described above, even when the recognition area of the preceding vehicle and the recognition area of the oncoming vehicle overlap, the oncoming vehicle recognition window area W _OO is _added to the oncoming vehicle recognition area and the vehicles in this area are recognized. Since it is determined from the position whether it is a preceding vehicle or an oncoming vehicle, it is possible to reliably include the range in which the oncoming vehicle is highly likely to exist, and to exclude the preceding vehicle and recognize the oncoming vehicle with high accuracy. You can

When the recognition of the preceding vehicle and the oncoming vehicle is completed in this way, the routine proceeds to step 204 of the inter-vehicle distance / relative speed measurement routine of FIG. In step 204,
Based on the positions on the screen of the other vehicle including the preceding vehicle and the oncoming vehicle detected by the above-described recognition processing, the vehicle angle θ representing the direction in which the specific other vehicle exists is obtained. The vehicle angle θ is set so that the value increases as the vehicle position deviates from the reference to the right side or the left side with the traveling direction of the vehicle 10 (center in the image) as a reference (0 °). In the next step 206, the actuator 82 is controlled so that the radar 80 rotates to a position corresponding to the vehicle angle θ. As a result, the vehicle is housed within the detection area of the radar 80. In step 208, radar 8
0 is operated to measure the inter-vehicle distance Li and the relative speed Vi with respect to the vehicle.

In step 210, it is determined whether or not the inter-vehicle distance Li and the relative speed Vi have been measured successfully. If the measurement is successful, the determination at step 210 is affirmative, and the process proceeds to step 214. Since the inter-vehicle distance Li and the relative speed Vi are measured by the radar 80, accurate values are obtained.

On the other hand, in the radar 80 of this embodiment, if the non-detection object is located at a long distance of, for example, 100 m or more, the detection capability is sharply lowered, and the measurement is likely to fail. For this reason,
When the measurement of the inter-vehicle distance fails, it is determined that the inter-vehicle distance to the other vehicle is 100 m or more, and predetermined values are set as the inter-vehicle distance Li and the relative speed Vi in step 212, and the process proceeds to step 214. Here, as the inter-vehicle distance Li, for example, 100 m can be set, and the relative speed V
For example, if the other vehicle is a preceding vehicle, i is 0 m /
If the other vehicle is an oncoming vehicle, it is possible to set a value that is twice the speed V of the own vehicle.

In step 214, the inter-vehicle distance Li and the relative speed Vi with the specific vehicle obtained as described above are stored in association with the measurement time T. In step 216, the inter-vehicle distance Li for all the vehicles detected in the recognition processing is
And whether or not the measurement of the relative speed Vi has been completed. If the determination in step 216 is negative, step 20
Returning to step 4, the determinations of steps 204 to 216 are repeated. If the determination in step 216 is affirmative, the inter-vehicle distance / relative speed measurement process ends.

Next, the light-shielding cam angle control processing of this embodiment will be described with reference to the flowchart of FIG. Although this light-shielding cam angle control processing is also executed at every cycle Tn, this cycle Tn is shorter (for example, about 1/4) than the cycle T of the inter-vehicle distance / relative speed measurement processing described above. At step 500, the current time Tn is fetched. In step 502, among the information of the vehicle-to-vehicle distance, the relative speed to the other vehicle, the relative speed, and the measurement time stored in the above-described vehicle-to-vehicle distance / relative speed measurement processing, the vehicle-to-vehicle distance Li, the relative speed Vi and The measurement time T is captured. In the next step 504, the elapsed time ΔTn from the measurement time T is calculated according to the following equation.

ΔTn = Tn−T (1) In step 506, the current vehicle-to-vehicle distance Lri with the specific other vehicle is estimated based on the elapsed time ΔTn using the following equation (2). In this equation (2), the inter-vehicle distance Lri is calculated on the assumption that the relative speed to the other vehicle is constant.

Lri = Li + Vi × ΔTn (2) In the next step 508, it is determined whether or not the estimation of the inter-vehicle distance Lri for all the vehicles detected by the above-described recognition processing is completed. If the determination in step 508 is negative, the process returns to step 502 and step 5 is performed for another vehicle.
The processing from 02 to step 506 is repeated. Step 5
If the determination of 08 is affirmative, the routine proceeds to step 510, and the shortest inter-vehicle distance Lr with the smallest value (shortest inter-vehicle distance) among the inter-vehicle distances Lri with other vehicles estimated above.
To extract.

In the next step 512, the gains for the actuators 40 and 41 are obtained based on the shortest inter-vehicle distance Lr extracted above using a map as shown in FIG. 24 as an example, and the actuator 4 is determined in accordance with this gain.
0 and 41 are driven to change the angle of the light shielding cam 40A.
As a result, the position of the cut line is controlled so that the position of the cut line moves downward as the value of the shortest inter-vehicle distance Lr becomes smaller, that is, the glare is not given to another vehicle at the shortest distance. Because it is done
It is prevented from giving glare to all other existing vehicles.

By repeating the above process, FIG.
The angle of the light shielding cam is controlled at the timing shown in FIG. That is, the inter-vehicle distance / relative speed measurement process is executed in each cycle T, and the inter-vehicle distance and the relative speed are measured in each cycle. In FIG. 25, the inter-vehicle distance measured in each cycle is indicated by “◯”. Further, the line connecting the circles indicates the change in the inter-vehicle distance estimated based on the measured inter-vehicle distance and the relative speed. The relative speed corresponds to the slope of the line. On the other hand, the light-shielding cam angle control processing is executed every cycle Tn, and the angle of the light-shielding cam is controlled based on the estimated inter-vehicle distance. Therefore, the angle of the light shielding cam is changed every cycle Tn as shown in FIG.

As described above, the cycle of executing the light-shielding cam angle control processing is not affected by the processing time of the inter-vehicle distance / relative speed measurement processing and can be executed in a short cycle. Therefore, even if it takes time to measure the inter-vehicle distance / relative speed, this effect can be eliminated, and glare can be prevented from being given to other vehicles.

In the above embodiment, the light distribution cam in front of the vehicle is controlled by the light shielding cam, but the light of the headlamp may be shielded by a light shielding plate or a shutter. Further, although the light distribution is controlled by blocking the light of the headlamp, the emission optical axis of the headlamp may be deflected.

Further, although the millimeter wave radar is used as the measuring means in the above embodiment, the present invention is not limited to this, and a radar device such as a laser radar can be applied. Alternatively, a geodimeter or a tellurometer may be used. Alternatively, the relative speed may be obtained by calculation based on the change in the measured inter-vehicle distance. Further, in the present embodiment, the inter-vehicle distance was estimated on the assumption that the relative speed is constant, but the degree of change in the relative speed is detected, and the inter-vehicle distance estimated based on the assumption is used for the change in the relative speed. It may be further modified according to the degree.

In the above embodiment, the inter-vehicle distance is estimated by using the elapsed time from the time when the inter-vehicle distance and the relative speed are measured. However, the execution cycle Tn of the light-shielding cam angle control process, that is, the previous cycle The vehicle-interval distance may be estimated based on the vehicle-interval distance, the relative speed, and the cycle Tn estimated last time using the elapsed time from the cycle.

Further, although the above embodiments have been described on the premise of left-hand traffic, it goes without saying that the present invention can also be applied to the case of right-hand traffic. In this case, the right side portion of the cut line 70 is inclined upward to the right, and the oncoming vehicle recognition area W _PO is set on the left side of the preceding vehicle recognition area W _P.

[0061]

As described above, according to the present invention, the other vehicle is detected every predetermined period based on the image signal obtained by capturing the situation in front of the vehicle, and the inter-vehicle distance and the relative speed to the other vehicle are detected. Is detected, a current vehicle distance to the other vehicle is estimated based on the period and the vehicle-to-vehicle distance and relative speed in a cycle shorter than the detection cycle of the other vehicle, and a headlamp based on the estimated vehicle-to-vehicle distance. Since at least one of the irradiation direction and the irradiation range is controlled, it is possible to obtain an excellent effect that glare can be prevented from being given to another vehicle.

[Brief description of drawings]

FIG. 1 is a perspective view of a front portion of a vehicle used in the present embodiment as seen obliquely from the front of the vehicle.

FIG. 2 is a perspective view showing a schematic configuration of a headlamp to which the present invention can be applied.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a block diagram showing a schematic configuration of a control device.

FIG. 5 is a flow chart illustrating an inter-vehicle distance / relative speed measurement process according to the present embodiment.

FIG. 6 is a flowchart illustrating a preceding vehicle recognition process.

FIG. 7 is a flowchart illustrating an oncoming vehicle recognition process.

FIG. 8 is a flowchart illustrating a light-shielding cam angle control process of this embodiment.

FIG. 9 is an image diagram for explaining a cut line displaced by an actuator.

10A is an image diagram of an image captured by a TV camera during the day, FIG. 10B is a conceptual diagram for explaining horizontal edge point integration processing, and FIG. 10C is a vertical edge detection processing. It is a conceptual diagram of.

FIG. 11 is a diagram showing a window area at the time of recognizing a white line.

FIG. 12 is a diagram showing a vehicle recognition area.

FIG. 13 is an image diagram for explaining that the vehicle recognition area is changed according to the vehicle speed.

FIG. 14 is a diagram showing a relationship between a vehicle speed and a correction width of an approximate straight line.

FIG. 15 is a diagram showing the relationship between the degree of a right curve road and the gain that determines the correction width of the approximate straight line on the right side.

FIG. 16 is a diagram showing the relationship between the degree of a right curve road and the gain that determines the correction width of an approximate straight line on the left side.

FIG. 17 is an image diagram showing window regions and correction widths for curved roads having different curvatures.

FIG. 18 is a diagram showing the relationship between the degree of a left curved road and the gain that determines the correction width of an approximate straight line on the right side.

FIG. 19 is a diagram showing the relationship between the degree of a left curved road and the gain that determines the correction width of the left approximate straight line.

FIG. 20 is a diagram showing a relationship between vehicle speed and window region correction widths α _RO and α _RO ′.

FIG. 21 is an image diagram showing an oncoming vehicle recognition area.

FIG. 22 is a diagram showing the relationship between the degree of a right curve road and the gain that determines the correction width on the right side of the window.

FIG. 23 is a diagram showing the relationship between the degree of a left curved road and the gain that determines the correction width on the right side of the window.

FIG. 24 is a diagram showing a relationship between an inter-vehicle distance and a gain of an actuator.

FIG. 25 is a diagram showing an execution cycle of an inter-vehicle distance / relative speed measurement process and a light-shielding cam angle control process, a change in the inter-vehicle distance estimated by these processes, and a control result of the light-shielding cam angle.

[Explanation of symbols]

 18 Head Lamp 20 Head Lamp 22 TV Camera 40 Actuator 42 Actuator 48 Image Processing Device 50 Control Device 80 Radar 82 Actuator

Claims (1)

[Claims] 1. A headlamp that can change at least one of an irradiation direction and an irradiation range, detects another vehicle based on an image signal obtained by imaging a situation in front of the vehicle at predetermined intervals, and detects the own vehicle. A vehicle headlight device for detecting at least one of an irradiation direction and an irradiation range of the headlamp based on the detected inter-vehicle distance with the detected other vehicle, and with the inter-vehicle distance. Detecting the relative speed with the other vehicle, estimating the current inter-vehicle distance with the other vehicle based on the cycle and the inter-vehicle distance and relative speed in a cycle shorter than the detection cycle of the other vehicle, and estimated At least one of the irradiation direction and the irradiation range of the headlamp is controlled based on the inter-vehicle distance.