Vehicular headlamp control device, vehicular headlamp control method and vehicular headlamp control program

Abstract

To provide a vehicular headlamp control device, a vehicular headlamp control method, and a vehicular headlamp control program, each enabling reduction of annoyance felt by an occupant.SOLUTION: A vehicular headlamp control device 100 controls a headlamp HL enabling adjustment of light quantity for each of light distribution areas. The vehicular headlamp control device 100 comprises: a high-luminance target detection portion 10 that detects a high-luminance target ahead of a vehicle V based on a camera image of a camera CA; a dimming control portion 50 that performs dimming control to reduce the amount of light in the light distribution area including the high-luminance target based on a detection result of the high-luminance target detection portion 10; and a dimming control determination portion 30 that determines whether brightness of a surrounding environment is a threshold or higher based on the camera image. The dimming control portion 50 does not perform the dimming control when the dimming control determination portion 30 determines that the brightness of the surrounding environment is the threshold or higher.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] One aspect of the present invention relates to a vehicle headlamp control device, a vehicle headlamp control method, and a vehicle headlamp control program.

Background Art

[0002] There is known a device that reduces glare of reflected light from a high-brightness object by a headlamp by performing dimming control to reduce the light amount of the headlamp of a vehicle according to the brightness of the high-brightness object (signs, billboards, etc.) (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a vehicle travels in a bright environment where there are many streetlights or buildings around (for example, some highways and urban areas), compared with when the vehicle travels in a dark environment where there are no streetlights around (for example, mountain roads), the passengers of the vehicle tend to be less likely to feel the glare of high-brightness objects. In this regard, in the above-described device, dimming control is performed even in a bright environment, and there is a possibility that the passengers feel the dimming control troublesome.

[0005] Therefore, one aspect of the present invention aims to provide a vehicle headlamp control device, a vehicle headlamp control method, and a vehicle headlamp control program capable of reducing the annoyance felt by passengers.

Means for Solving the Problems

[0006] The vehicle headlamp control device according to one aspect of the present invention is a device that controls a headlamp capable of adjusting the light amount for each of a plurality of light distribution regions. Based on the imaging result of an imaging device that images the front of the vehicle, it includes a high-brightness target detection unit that detects a high-brightness target in front of the vehicle, a dimming control unit that performs dimming control to reduce the light amount of the light distribution region including the high-brightness target based on the detection result of the high-brightness target detection unit, and a dimming control determination unit that determines whether the brightness of the surrounding environment is equal to or higher than a threshold value based on the imaging result of the imaging device. The dimming control unit does not perform dimming control when the dimming control determination unit determines that the brightness of the surrounding environment is equal to or higher than the threshold value.

[0007] In the vehicle headlamp control device according to one aspect of the present invention, the dimming control determination unit may determine that the brightness of the surrounding environment is equal to or higher than the threshold value when the brightness of the road surface around the vehicle is equal to or higher than the threshold value, the brightness of the sky around the vehicle is equal to or higher than the threshold value, or there are a plurality of street lamps around the vehicle and the interval between the plurality of street lamps is equal to or less than a certain interval.

[0008] The vehicle headlamp control method according to one aspect of the present invention is a method for controlling a headlamp capable of adjusting the light amount for each of a plurality of light distribution regions. It includes a high-brightness target detection step of detecting a high-brightness target in front of the vehicle based on the imaging result of an imaging device that images the front of the vehicle, a dimming control step of performing dimming control to reduce the light amount of the light distribution region including the high-brightness target based on the detection result of the high-brightness target detection step, and a dimming control determination step of determining whether the brightness of the surrounding environment is equal to or higher than a threshold value based on the imaging result of the imaging device. In the dimming control step, dimming control is not performed when it is determined in the dimming control determination step that the brightness of the surrounding environment is equal to or higher than the threshold value.

[0009] A vehicle headlamp control program according to an aspect of the present invention is a program for controlling a headlamp capable of adjusting the light quantity for each of a plurality of light distribution regions. Based on the imaging result of an imaging device that images the front of the vehicle, a high-brightness target detection step of detecting a high-brightness target in front of the vehicle, a dimming control step of performing dimming control to reduce the light quantity of the light distribution region including the high-brightness target based on the detection result of the high-brightness target detection step, and a dimming control determination step of determining whether the brightness of the surrounding environment is equal to or higher than a threshold value based on the imaging result of the imaging device are executed by a computer. In the dimming control step, when it is determined in the dimming control determination step that the brightness of the surrounding environment is equal to or higher than the threshold value, the dimming control is not performed.

Advantages of the Invention

[0010] According to an aspect of the present invention, it is possible to provide a vehicle headlamp control device, a vehicle headlamp control method, and a vehicle headlamp control program capable of reducing the annoyance felt by a passenger.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0012] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or corresponding elements are denoted by the same reference numerals, and duplicate descriptions are omitted.

[0013] As shown in FIG. 1, the vehicle headlamp control device 100 according to the embodiment is a device that controls the headlamp HL of the vehicle V. The vehicle V may be a passenger car or a freight car. The vehicle V can accommodate one or more passengers. The vehicle V may be an autonomous driving vehicle capable of autonomous driving. The vehicle V may be capable of manual driving by a driver. The vehicle headlamp control device 100 has a light distribution control function (for example, an Adaptive High beam System (AHS)).

[0014] The headlamp HL is a lamp that illuminates the front of the vehicle V. The headlamp HL is configured to be able to adjust the light quantity for each of a plurality of light distribution regions (irradiation regions). For example, the headlamp HL includes a plurality of LEDs arranged side by side, and by adjusting the energization amount of any LED, the irradiation amount in any light distribution region can be increased or decreased. The vehicle headlamp control device 100 includes an Electronic Control Unit (ECU) 1.

[0015] As shown in FIG. 2, the ECU 1 is a computer having a processor 1A, a main memory unit 1B, and an auxiliary storage unit 1C as a hardware configuration. The processor 1A is an arithmetic unit that executes programs. Examples of the processor include a CPU [Central Processing Unit], but the type of the processor 1A is not limited to these. The main memory unit 1B is a device that stores programs and calculation results output from the processor 1A. The main memory unit 1B is composed of, for example, at least one of a ROM [Read Only Memory] and a RAM [Random Access Memory]. The auxiliary storage unit 1C is a device capable of storing a larger amount of data than the main memory unit 1B. The auxiliary storage unit 1C is composed of, for example, a non-volatile storage medium such as a hard disk or a flash memory. The auxiliary storage unit 1C stores a vehicle headlight control program P and various data. The vehicle headlight control program P is a program for controlling the headlamp HL, and causes the ECU 1 (processor 1A) to execute a high-brightness target detection step, a dimming control step, and a dimming control determination step, which will be described later.

[0016] As shown in FIG. 1, the ECU 1 has, as a functional configuration, a high-brightness target detection unit 10, a surrounding environment recognition unit 20, a dimming control determination unit 30, a dimming amount setting unit 40, and a dimming control unit 50. The high-brightness target detection unit 10 detects a high-brightness target in front of the vehicle V based on a camera image (imaging result) of a camera (imaging device) CA that images the front of the vehicle V. The high-brightness target is a target having a luminance higher than a predetermined luminance and is not particularly limited. The high-brightness target may be a self-luminous target that emits light by itself, or may be a target that emits light by reflection of light such as the headlamp HL. Examples of the high-brightness target include a billboard, a signboard, and another vehicle with its lamp lit.

[0017] The high-brightness object detection unit 10 includes an object area calculation unit 11 that calculates the area of an object existing in front of the vehicle V from a camera image, an object brightness calculation unit 12 that calculates the brightness of an object existing in front of the vehicle V from the camera image, and an object coordinate calculation unit 13 that calculates the coordinates of an object existing in front of the vehicle V from the camera image. The methods for calculating the area, brightness, and coordinates of the object are not particularly limited, and various known methods may be used. The area of the object corresponds to, for example, the size of the object on the camera image (the projected area when viewed from the vehicle V). The coordinates of the object may be coordinates based on an arbitrary predetermined position, and correspond to, for example, the position of the object on the camera image. For example, the high-brightness object detection unit 10 detects an object with a brightness calculated by the object brightness calculation unit 12 higher than a predetermined brightness as a high-brightness object, and detects the area and coordinates of the high-brightness object by the object area calculation unit 11 and the object coordinate calculation unit 13, respectively.

[0018] The surrounding environment recognition unit 20 recognizes the surrounding environment, which is the environment around the vehicle V, based on the camera image. Specifically, the surrounding environment recognition unit 20 includes a surrounding illuminance calculation unit 21 that calculates the illuminance of the road surface and the sky around the vehicle V from the camera image, and a street lamp detection unit 22 that detects the positions of a plurality of street lamps around the vehicle V from the camera image. The street lamps are not particularly limited, and various known street lamps may be used. The methods for calculating the illuminance and the positions of the street lamps are not particularly limited, and various known methods may be used.

[0019] The dimming control determination unit 30 determines, based on the camera image, whether the brightness of the surrounding environment of the vehicle V is equal to or higher than a threshold value (brightness suitable for performing dimming control). Specifically, the dimming control determination unit 30 determines that the brightness of the surrounding environment of the vehicle V is equal to or higher than the threshold value (not brightness suitable for performing dimming control) when the surrounding environment of the vehicle V recognized from the camera image by the surrounding environment recognition unit 20 is bright enough that the occupants of the vehicle V are less likely to feel dazzled by the high-brightness object. The dimming control is a control for reducing the light amount of at least any one of the plurality of light distribution areas (hereinafter, also simply referred to as "light distribution areas") in the headlamp HL that includes the high-brightness object.

[0020] More specifically, the dimming control determination unit 30 determines that the brightness of the surrounding environment is equal to or greater than the threshold value when the brightness of the road surface around the vehicle V is equal to or greater than the threshold value, the brightness of the sky around the vehicle V is equal to or greater than the threshold value, or there are a plurality of streetlights around the vehicle V and the interval between the plurality of streetlights is equal to or less than a certain interval. The threshold value may be predetermined and stored in advance, or may be acquired by communication or the like. The threshold value of the brightness of the road surface and the threshold value of the brightness of the sky may be the same or different. The certain interval may be predetermined and stored in advance, or may be acquired by communication or the like.

[0021] In addition, the dimming control determination unit 30 further determines whether the start condition of the dimming control is satisfied based on the position (coordinates) and size (area) of the high-brightness target detected by the high-brightness target detection unit 10. Specifically, the dimming control determination unit 30 determines that the start condition of the dimming control is satisfied when the position of the high-brightness target is located within a predetermined range in the center of the camera image and the size of the high-brightness target is equal to or greater than a predetermined size. The predetermined range and the predetermined size are not particularly limited and may be preset and stored in the ECU 1 in advance. The predetermined range and the predetermined size may be fixed values or variable values that change according to various inputs or conditions.

[0022] The dimming amount setting unit 40 sets the dimming amount of the dimming control. The dimming amount setting unit 40 may set a predetermined amount (50 percent) as the dimming amount in advance. The dimming control unit 50 performs dimming control based on the detection result of the high-brightness target detection unit 10. Here, the dimming control unit 50 controls the headlamp HL so that the light amount of one or a plurality of light distribution regions including the high-brightness target detected by the high-brightness target detection unit 10 becomes the dimming amount set by the dimming amount setting unit 40 as the dimming control.

[0023] When the brightness of the surrounding environment is determined to be equal to or higher than the threshold value in the dimming control determination unit 30, the dimming control unit 50 does not perform dimming control. In other words, when the brightness of the surrounding environment is determined not to be equal to or higher than the threshold value in the dimming control determination unit 30, the dimming control unit 50 performs dimming control. When the dimming control unit 50 determines that the start condition of dimming control is satisfied in the dimming control determination unit 30, the dimming control unit 50 performs dimming control. In other words, when the dimming control unit 50 determines that the start condition of dimming control is not satisfied in the dimming control determination unit 30, the dimming control unit 50 does not perform dimming control.

[0024] Next, an example of the vehicle headlamp control method by the vehicle headlamp control device 100 of the present embodiment will be described with reference to the flowchart of FIG. 3. The following series of processes are repeatedly executed at predetermined intervals, for example, when the vehicle V is running and the headlamp HL is operating. The vehicle headlamp control method is a method for controlling the headlamp HL and corresponds to the process by the vehicle headlamp control program P (see FIG. 2).

[0025] As shown in FIG. 3, first, in the ECU 1, a camera image is acquired from the camera CA (step S1). Based on the camera image, the high-brightness target detection unit 10 detects a high-brightness target in front of the vehicle V (step S2). The surrounding environment recognition unit 20 recognizes the surrounding environment of the vehicle V based on the camera image. The dimming control determination unit 30 determines whether the brightness of the surrounding environment of the vehicle V recognized by the surrounding environment recognition unit 20 is equal to or higher than the threshold value (step S3).

[0026] If the result in step S3 is YES, the dimming control determination unit 30 determines whether the start condition of dimming control is satisfied (step S4). If the result in step S4 is YES, the dimming amount setting unit 40 sets the dimming amount (step S5). Then, the dimming control unit 50 performs dimming control (step S6). On the other hand, if the result in step S3 is NO or the result in step S4 is NO, the process ends without performing dimming control.

[0027] Note that the above step S2 corresponds to a high-brightness target detection step. The above steps S3 and S4 correspond to a dimming control determination step. The above step S6, which is not executed when NO in the above step S3 or NO in the above step S4, corresponds to a dimming control step.

[0028] As described above, in this embodiment, in a situation where the brightness of the surrounding environment of the vehicle V is sufficient, since it is difficult to feel glare from high-brightness targets, dimming control is not implemented. Thereby, it is possible to reduce the annoyance felt by the occupant regarding unnecessary dimming control. Also, by performing dimming control in a situation where the surrounding environment of the vehicle V is bright, it is possible to suppress the darkening of signs or billboards and the difficulty in grasping the content (decrease in visibility).

[0029] In this embodiment, when the brightness of the road surface around the vehicle V is equal to or higher than a threshold value, the brightness of the sky around the vehicle V is equal to or higher than a threshold value, or there are a plurality of streetlights around the vehicle V and the interval between the plurality of streetlights is equal to or less than a certain interval, it is determined that the brightness of the surrounding environment is equal to or higher than the threshold value. In this case, it is possible to specifically implement the determination as to whether the brightness of the surrounding environment is equal to or higher than the threshold value.

[0030] In this embodiment, when a high-brightness target is located in a predetermined range at the center in the camera image and the size of the high-brightness target is equal to or larger than a predetermined size, it is determined that the start condition for dimming control is satisfied, and dimming control is implemented. In this case, since dimming control is not implemented when the start condition is not satisfied, it is possible to further reduce the annoyance felt by the occupant regarding unnecessary dimming control.

[0031] As described above, the embodiments have been described, but one aspect of the present invention is not limited to the above embodiments. One aspect of the present invention can be implemented in various forms with various changes and improvements based on the knowledge of those skilled in the art, including the above embodiments.

[0032] In the above embodiment, the camera CA is adopted as the imaging device, but the present invention is not limited thereto, and various known imaging devices may be adopted. In the above embodiment, the headlamp HL is adopted as the headlamp, but the present invention is not limited thereto, and various known headlamps may be adopted.

Explanation of Reference Numerals

[0033] 1…ECU (computer), 10…high-brightness target detection unit, 20…surrounding environment recognition unit, 30…dimming control determination unit, 40…dimming amount setting unit, 50…dimming control unit, 100…vehicle headlamp control device, CA…camera (imaging device), HL…headlamp (headlamp), P…vehicle headlamp control program, V…vehicle.

Claims

1. A device for controlling a headlamp capable of adjusting a light amount for each of a plurality of light distribution areas, a high-brightness target detection unit that detects a high-brightness target ahead of the vehicle based on an imaging result of an imaging device that images an area ahead of the vehicle; a dimming control unit that performs dimming control to reduce the amount of light in the light distribution area including the high-brightness target based on a detection result of the high-brightness target detection unit; a dimming control determination unit that determines whether or not the brightness of the surrounding environment is equal to or greater than a threshold based on an imaging result of the imaging device, The dimming control unit is A vehicle headlamp control device that does not perform the dimming control when the dimming control determination unit determines that the brightness of the surrounding environment is equal to or greater than the threshold value.

2. The dimming control determination unit 2. The vehicle headlamp control device according to claim 1, wherein the brightness of the surrounding environment is determined to be equal to or greater than the threshold value when the brightness of the road surface around the vehicle is equal to or greater than a threshold value, the brightness of the sky around the vehicle is equal to or greater than a threshold value, or when there are multiple street lights around the vehicle and the spacing between the multiple street lights is equal to or less than a certain interval.

3. The dimming control determination unit determining that the dimming control start condition is satisfied when the high-brightness target is located within a predetermined central range in an image captured by the imaging device and the size of the high-brightness target is equal to or larger than a predetermined size; The dimming control unit is The vehicle headlamp control device according to claim 1 , further comprising: a dimming control determining unit that determines that the start condition for the dimming control is satisfied, and then performs the dimming control.

4. A method for controlling a headlamp capable of adjusting a light amount for each of a plurality of light distribution areas, comprising: a high-brightness target detection step of detecting a high-brightness target ahead of the vehicle based on an imaging result of an imaging device that images an area ahead of the vehicle; a dimming control step of performing dimming control to reduce the amount of light in the light distribution area including the high-brightness target based on a detection result of the high-brightness target detection step; and a dimming control determination step of determining whether or not the brightness of the surrounding environment is equal to or greater than a threshold based on an imaging result of the imaging device, In the dimming control step, The vehicle headlamp control method includes not performing the dimming control when it is determined in the dimming control determination step that the brightness of the surrounding environment is equal to or greater than the threshold value. 。

5. A program for controlling a headlamp capable of adjusting a light amount for each of a plurality of light distribution areas, a high-brightness target detection step of detecting a high-brightness target ahead of the vehicle based on an imaging result of an imaging device that images an area ahead of the vehicle; a dimming control step of performing dimming control to reduce the amount of light in the light distribution area including the high-brightness target based on a detection result of the high-brightness target detection step; a dimming control determination step of determining whether or not the brightness of the surrounding environment is equal to or greater than a threshold based on an imaging result of the imaging device; In the dimming control step, the dimming control is not performed when it is determined in the dimming control determination step that the brightness of the surrounding environment is equal to or greater than the threshold value.

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