Headlamp control device and vehicle

Abstract

To provide a headlamp control device and a vehicle which can secure a front visual field of a driver at night, when adaptive driving beam (ADB) operation by vehicle speed is restricted.SOLUTION: A headlamp control device 1 includes: an imaging part 10 for imaging a front image of an own vehicle; a front vehicle detection part 20 for detecting a front vehicle existing in a front region of the own vehicle; a front vehicle position calculation part 30 for calculating the position of the front vehicle; a speed determination part 40 for determining whether or not the travel speed of the own vehicle is lower than first speed; a brake state detection part 50 for detecting whether or not an automatic brake is in operation; a headlamp part 60 for switching lighting of the headlamp, and lighting the front of the vehicle; and a headlamp control part 70 for controlling the lighting of the headlamp part 60, on the basis of the detection result of the front vehicle detection part 20 and the speed determination part 40.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a headlamp control device and a vehicle.

Background Art

[0002] In recent years, an adaptive driving beam (ADB) headlamp that enhances the lighting effect in the front area of the host vehicle and prevents glare to preceding vehicles, oncoming vehicles, etc. present in the front area of the host vehicle has been put into practical use. The ADB headlamp checks the situation of preceding vehicles, oncoming vehicles, etc., performs control to block the light that dazzles the preceding vehicles and oncoming vehicles, and expands the driver's forward field of view at night. Here, as an ADB headlamp, when an object is detected from an image captured by a camera, a technique has been proposed in which the position of the object is detected and the irradiation area of the illumination light by the lamp unit is controlled based on the detected position (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] However, in US regulations, when the vehicle speed is less than the legal speed, the ADB operation is prohibited. For example, when the automatic brake for avoiding a collision with an object (such as a pedestrian or a vehicle) in front of the host vehicle is activated and the vehicle speed becomes less than the legal speed, the headlamp lighting switches to the low beam, and there is a problem of losing sight of the object in front. Furthermore, when the ADB (Adaptive Dynamics) system is in operation, if the vehicle slows down before a curve on a mountain road or similar terrain, and the vehicle speed falls below the legal speed limit, the headlights switch to low beam, which reduces the driver's forward visibility at night.

[0005] Therefore, the present invention has been made in view of the above-mentioned problems, and aims to provide a headlamp control device and a vehicle that can ensure the driver's forward visibility at night, even when there is a limitation on ADB operation due to the vehicle's driving speed. [Means for solving the problem]

[0006] Embodiment 1; One or more embodiments of the present invention include a forward vehicle detection unit that detects a forward vehicle in the area in front of the vehicle, a speed determination unit that determines whether the vehicle's speed has fallen below a first speed, and a headlamp control unit that controls the illumination of the headlamp based on the detection results of the forward vehicle detection unit and the speed determination unit, wherein the headlamp control unit has a first mode and a second mode, and in the first mode, when the forward vehicle detection unit detects the forward vehicle, it controls the illumination area of ​​the headlamp based on the position of the forward vehicle, and The proposed headlamp control device is configured such that, if no vehicle is detected in front, the headlamp is switched to high beam; the second mode is configured such that, if the vehicle in front is detected by the vehicle in front detection unit, the headlamp is switched to low beam, and if the vehicle in front is not detected by the vehicle in front detection unit, the headlamp is switched to high beam; and the headlamp control unit transitions to the second mode in the first mode if the speed determination unit determines that the vehicle's speed has fallen below a first speed.

[0007] Embodiment 2; One or more embodiments of the present invention include a brake state detection unit that detects whether or not the automatic brake is activated, a speed determination unit that further determines whether or not the driving speed has fallen below a second speed which is slower than the first speed, and a headlamp control unit that, if the speed determination unit determines that the driving speed of the vehicle has fallen below the second speed and the brake state detection unit determines that the automatic brake is not activated, a headlamp control device is proposed that switches the illumination of the headlamp to low beam.

[0008] Embodiment 3; One or more embodiments of the present invention propose a headlamp control device in which the headlamp control unit transitions to the first mode when the speed determination unit determines that the vehicle's travel speed exceeds a third speed which is faster than a first speed, and transitions to the second mode when the speed determination unit determines that the vehicle's travel speed exceeds a fourth speed which is faster than a second speed, and a predetermined speed difference is set between the first speed and the third speed, and between the second speed and the fourth speed.

[0009] Embodiment 4; Embodiments 1 or more of the present invention propose a vehicle equipped with a headlamp control device as described in any of Embodiments 1 to 3. [Effects of the Invention]

[0010] According to one or more embodiments of the present invention, even when the operation of ADB is limited by the vehicle's speed, it is possible to ensure the driver's forward visibility at night. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows the configuration of a headlamp control device according to an embodiment of the present invention. [Figure 2] This figure shows the lighting pattern of the headlamp controlled by the headlamp control device according to an embodiment of the present invention. [Figure 3] This figure shows the relationship between the lighting mode and driving speed of a headlamp control device according to an embodiment of the present invention. [Modes for carrying out the invention]

[0012] <Embodiment> The headlamp control device 1 according to this embodiment will be described with reference to Figures 1 to 3.

[0013] <Configuration of Headlamp Control Device 1> As shown in Figure 1, the headlamp control device 1 is a device that controls the illumination of the headlamps of a vehicle, and comprises an imaging unit 10, a forward vehicle detection unit 20, a forward vehicle position calculation unit 30, a speed determination unit 40, a brake state detection unit 50, a headlamp control unit 70, and a headlamp unit 60.

[0014] The imaging unit 10 is composed of, for example, a monocular camera or a stereo camera, and captures an image of the area in front of the vehicle and transmits that image to the forward vehicle detection unit 20, which will be described later.

[0015] The forward vehicle detection unit 20 detects vehicles in the area in front of its own vehicle and transmits the detection result to the forward vehicle position calculation unit 30 and the headlamp control unit 70, which will be described later. Specifically, the system analyzes the image received from the imaging unit 10 to detect whether or not there is a vehicle ahead or an oncoming vehicle in the area in front of the vehicle.

[0016] When the forward vehicle position calculation unit 30 receives information from the forward vehicle detection unit 20 indicating that a preceding vehicle or oncoming vehicle has been detected in the area in front of its own vehicle, it calculates the position information of the detected preceding vehicle or oncoming vehicle and transmits it to the headlamp control unit 70. Specifically, the system analyzes the image received from the imaging unit 10 and calculates the position information of the preceding vehicle relative to the vehicle's own reference position (for example, the position of the headlamp light source).

[0017] The speed determination unit 40 detects the traveling speed of the host vehicle, determines whether the traveling speed is lower than the first speed and the second speed, and transmits the determination result to the headlamp control unit 70 described later. Also, the speed determination unit 40 detects the traveling speed of the host vehicle, determines whether the traveling speed is higher than the third speed and the fourth speed, and transmits the determination result to the headlamp control unit 70 described later. Specifically, the speed determination unit 40, for example, acquires vehicle speed pulses, calculates the traveling speed of the host vehicle, and performs speed determination. Details regarding the first speed to the fourth speed will be described later.

[0018] The brake state detection unit 50 detects whether an automatic brake for avoiding a collision with an object existing in front of the host vehicle is currently operating, and transmits the detection result to the headlamp control unit 70. Specifically, the brake state detection unit 50, for example, acquires information indicating the operating state of the brake from a brake control unit (not shown) and detects whether the automatic brake is operating.

[0019] The headlamp unit 60 switches on the headlamp according to an instruction from the headlamp control unit 70 to illuminate the front of the vehicle. Specifically, as shown in FIG. 2, the headlamp unit 60 switches on the headlamp to any one of low beam (passing headlamp), high beam (driving headlamp), and ADB (Adaptive Driving Beam) according to an instruction from the headlamp control unit 70 described later.

[0020] As shown in (1) of FIG. 2, when the headlamp unit 60 irradiates the front of the vehicle with a low beam (passing headlamp), the driver can, for example, confirm traffic obstacles such as a preceding vehicle, an oncoming vehicle, or a person located 40 m ahead. That is, when irradiating the front of the vehicle with a low beam (passing headlamp), it is possible to prevent dazzling the driver of a preceding vehicle, an oncoming vehicle, etc. existing in the front area of the host vehicle, but it is difficult to confirm distant objects. As shown in Figure 2(2), when the headlamp unit 60 illuminates the area in front of the vehicle with high beams (driving headlights), the driver can see objects that may be obstacles to traffic, such as a preceding vehicle, an oncoming vehicle, or a person, located 100m ahead. In other words, when the front of the vehicle is illuminated with high beams (driving headlights), the driver can see distant objects, but it can dazzle drivers of other vehicles traveling within the illuminated area. As shown in Figure 2(3), when the headlamp unit 60 illuminates the area in front of the vehicle by ADB, the light distribution of the headlamp is controlled so that the light does not reach the position of a preceding vehicle or an oncoming vehicle traveling in front of the vehicle, allowing the driver to see, for example, a preceding vehicle, an oncoming vehicle, or a person that could be a traffic obstacle 100m ahead. In other words, when the ADB illuminates the area in front of the vehicle, the driver can see distant objects, and the illumination does not cause glare to drivers of other vehicles traveling within the illuminated area. When illuminating the area in front of the vehicle using ADB, the headlamp control unit 70 controls the light distribution of the headlamp unit 60 based on the position information of the vehicle ahead detected by the forward vehicle position calculation unit 30.

[0021] The headlamp control unit 70 controls the overall operation of the headlamp control device 1 according to a control program stored in a ROM or the like (not shown). The headlamp control unit 70 controls the illumination of the headlamp unit 60 based on the detection results of the forward vehicle detection unit 20 and the speed determination unit 40. The headlamp control unit 70 has a first mode and a second mode, which are the lighting modes of the headlamps. When the headlamp lighting mode is set to the first mode, the headlamp control unit 70 controls the illumination area of ​​the headlamp based on the position of the vehicle ahead if the vehicle ahead is detected by the vehicle ahead detection unit 20, and controls the headlamp to switch to high beam when the vehicle ahead is not detected by the vehicle ahead detection unit 20. Furthermore, when the headlamp lighting mode is set to the second mode, the headlamp control unit 70 controls the headlamp to switch to low beam when the forward vehicle detection unit 20 detects a vehicle ahead, and switches to high beam when the forward vehicle detection unit 20 does not detect a vehicle ahead. Furthermore, in the first mode, if the speed determination unit 40 determines that the vehicle's speed has fallen below the first speed, the headlamp control unit 70 transitions the control to the second mode. Furthermore, the headlamp control unit 70 has a low beam as a headlamp lighting mode, and when the headlamp lighting mode is set to low beam, it controls the lighting of the low beam.

[0022] <Processing by the headlamp control unit 70> Figure 3 will be used to explain the details of the processing of the headlamp control unit 70. Based on the determination result of the speed determination unit 40 and the detection result of the brake state detection unit 50, the headlamp control unit 70 controls the illumination of the headlamp by transitioning the illumination mode of the headlamp to one of the first mode, the second mode, or low beam.

[0023] As shown in Figure 3, when the speed determination unit 40 determines that the vehicle's speed exceeds the third speed, the headlamp control unit 70 transitions the lighting mode from the second mode to the first mode. When the lighting mode is set to the first mode, the headlamp control unit 70 receives information from the forward vehicle detection unit 20 that a vehicle has been detected ahead, and transmits an instruction to the headlamp unit 60 to activate ADB. On the other hand, when the headlamp control unit 70 receives information from the forward vehicle detection unit 20 indicating that no vehicle has been detected ahead, it transmits an instruction to the headlamp unit 60 to turn on the high beams.

[0024] The headlamp control unit 70, when the speed determination unit 40 determines that the vehicle's speed has fallen below a first speed, transitions the lighting mode from the first mode to the second mode, and when it determines that the vehicle's speed has exceeded a fourth speed, transitions the lighting mode from low beam to the second mode. When the lighting mode is set to the second mode, the headlamp control unit 70 receives information from the front vehicle detection unit 20 that a vehicle has been detected ahead, and transmits an instruction to the headlamp unit 60 to turn on the low beams. On the other hand, when the headlamp control unit 70 receives information from the forward vehicle detection unit 20 indicating that no vehicle has been detected ahead, it transmits an instruction to the headlamp unit 60 to turn on the high beams.

[0025] The headlamp control unit 70 switches the lighting mode to low beam if the speed determination unit 40 determines that the vehicle's speed has fallen below the second speed, and the brake state detection unit 50 determines that the automatic brake is not in operation. Furthermore, if the lighting mode is set to low beam, the headlamp control unit 70 transmits an instruction to the headlamp unit 60 to turn on the low beam, regardless of the detection result of the forward vehicle detection unit 20. On the other hand, if the speed determination unit 40 determines that the vehicle's speed has fallen below the second speed, and the brake state detection unit 50 determines that automatic braking is in progress, the headlamp control unit 70 continues in the second mode. In other words, even if the automatic braking system is activated to avoid a collision with an object (vehicle, person, etc.) in front of the vehicle, and the vehicle's speed is reduced to a speed below the second speed, the headlamp control unit 70 will turn on the high beams if there is no vehicle in front. Furthermore, the headlamp control unit 70 continuously checks the detection results of the brake state detection unit 50, and when it confirms that automatic braking has ended, it switches the lighting mode to low beam.

[0026] Here, we will explain the setting values ​​for the first to fourth speeds mentioned above. The first speed setting is set to a speed below the legal limit at which ADB operation is prohibited in the United States, for example, while the third speed setting is set to a speed faster than the first speed. In other words, a predetermined speed difference is set between the vehicle speed at which the headlight illumination mode transitions from the second mode to the first mode (the third speed) and the vehicle speed at which it transitions from the first mode to the second mode (the first speed). Furthermore, the second speed setting is set to a speed slower than the legal speed limit, and the fourth speed setting is set to a speed faster than the second speed. In other words, a predetermined speed difference is set between the vehicle speed at which the headlight illumination mode transitions from low beam to the second mode (the fourth speed) and the vehicle speed at which it transitions from the second mode back to low beam (the second speed). Furthermore, the fourth speed setting is set to a slower speed than the third speed setting, and the second speed setting is set to a slower speed than the first speed setting.

[0027] <Effects and Actions> As described above, the headlamp control device 1 according to this embodiment includes an imaging unit 10 that captures an image of the area in front of the vehicle, a forward vehicle detection unit 20 that detects a vehicle in the area in front of the vehicle, a forward vehicle position calculation unit 30 that calculates the position of the vehicle in front, a speed determination unit 40 that determines whether the vehicle's driving speed has fallen below a first speed, a brake state detection unit 50 that detects whether the automatic brake is in operation, a headlamp unit 60 that switches the lighting of the headlamps to illuminate the area in front of the vehicle, and a headlamp control unit 70 that controls the lighting of the headlamp unit 60 based on the detection results of the forward vehicle detection unit 20 and the speed determination unit 40. When the speed determination unit 40 determines that the vehicle's speed has fallen below the first speed (the legal speed at which ADB operation is prohibited), the headlamp control unit 70 switches the headlamp lighting mode to the second mode. If the forward vehicle detection unit 20 detects a vehicle ahead, the headlamp control unit 70 sends an instruction signal to the headlamp unit 60 to turn on the low beams. If the forward vehicle detection unit 20 does not detect a vehicle ahead, the headlamp control unit 70 sends an instruction signal to the headlamp unit 60 to turn on the high beams. In other words, when the vehicle's speed falls below the first speed (the legal speed at which ADB operation is prohibited), the high beams or low beams will be activated depending on whether there is a vehicle in front. As a result, even at vehicle speeds where ADB (Adaptive Driving Beam) operation is prohibited, the headlights will switch to high beam mode if there is no vehicle ahead, thus ensuring the driver's forward visibility at night. Furthermore, the headlamp control unit 70 can prevent dazzling drivers of preceding or oncoming vehicles in the area in front of the vehicle by switching the headlamp to low beam when a vehicle is detected in front of the vehicle by the forward vehicle detection unit 20.

[0028] Furthermore, when driving on a curved mountain road or similar at a speed faster than the first speed, even if the vehicle's speed decreases to below the first speed (the legal speed at which ADB operation is prohibited) before the curve, if there is no vehicle in front, the headlights will switch to high beam, thus ensuring the driver's forward visibility at night.

[0029] Furthermore, even if, while ADB is in operation, the automatic brakes are activated to avoid a collision with an object (vehicle, person, etc.) in front of the vehicle, and the vehicle's speed is reduced to a speed below the first speed (the legal speed at which ADB operation is prohibited), the headlamp control unit 70 will switch the headlamps to high beam if there is no vehicle in front, thereby preventing the driver from losing sight of the object in front of the vehicle. This allows drivers to perform driving maneuvers more precisely to avoid collisions with objects.

[0030] Furthermore, if the speed determination unit 40 determines that the vehicle's speed has fallen below the second speed, and the brake state detection unit 50 determines that the automatic brake is not in operation, the headlamp control unit 70 switches the headlamp illumination state to low beam. This means that when the automatic braking system is not in operation, the headlights will remain on low beam, preventing dazzling the driver of the vehicle in front. On the other hand, if automatic braking is in progress, the headlamp control unit 70 does not change the headlamp lighting mode and continues in the second mode. If the forward vehicle detection unit 20 does not detect a vehicle ahead, the headlamp lights up to high beam, and if a vehicle ahead is detected, the headlamp lights up to low beam. As a result, even if the automatic braking system is activated to avoid a collision with an object (vehicle, person, etc.) in front of the vehicle and the driving speed is reduced to a speed below the second speed, the headlamp control unit 70 will switch the headlights to high beam if no vehicle is detected in front of the vehicle, thereby preventing the driver from losing sight of the object in front of the vehicle.

[0031] A predetermined speed difference (hysteresis) is set between the vehicle speed at which the headlight illumination mode transitions from the second mode to the first mode (third speed) and the vehicle speed at which it transitions from the first mode to the second mode (first speed). Furthermore, a predetermined speed difference (hysteresis) is set between the vehicle speed at which the headlight illumination mode transitions from low beam to the second mode (fourth speed) and the vehicle speed at which it transitions from the second mode back to low beam (second speed). For example, when the vehicle's speed falls below the second speed, the lighting mode switches from the second mode to low beam. However, even if the vehicle accelerates to a speed exceeding the second speed immediately afterward, the lighting mode will not switch from low beam to the second mode until the vehicle speed exceeds the fourth speed, because a predetermined speed difference is set. This prevents hunting during transitions between lighting modes.

[0032] <Example 1> The headlamp control device 1 described above detects the presence or absence of a vehicle ahead and switches the headlamp's illumination state accordingly. However, it may also be configured to detect pedestrians in front of the vehicle and switch the illumination state accordingly. In other words, even if no vehicle is detected in front of the vehicle, if a pedestrian or other person walking towards the vehicle is detected, the headlights will switch to low beam. This prevents dazzling pedestrians and other objects in the area in front of the vehicle.

[0033] <Modification 2> The forward vehicle detection unit 20 described above detected the presence or absence of a vehicle based on the image of the front of the vehicle received from the imaging unit 10, but it may also be possible to detect the presence or absence of a vehicle using Lidar (light detection and ranging) or the like. This allows for accurate detection of the presence or absence of vehicles traveling at a distance from the vehicle itself.

[0034] While embodiments of this invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments and includes designs and the like that do not depart from the spirit of this invention. [Explanation of symbols]

[0035] 1; Headlamp control device 10; Imaging Unit 20; Forward vehicle detection unit 30; Forward Vehicle Position Calculation Unit 40;Speed ​​judgment section 50; Brake state detection unit 60; Headlamp section 70; Headlamp control unit

Claims

1. A forward vehicle detection unit that detects a vehicle in the area in front of the vehicle, A speed determination unit that determines whether the vehicle's speed has fallen below a first speed, The system includes a headlamp control unit that controls the illumination of the headlamps based on the detection results of the forward vehicle detection unit and the speed determination unit, The headlamp control unit has a first mode and a second mode, The first mode is, If the forward vehicle detection unit detects a vehicle ahead, it controls the illumination area of ​​the headlamp to vary based on the position of the vehicle ahead. If the forward vehicle detection unit does not detect a vehicle ahead, it controls the headlamp to switch to high beam. The second mode is, The control system switches the headlights to low beam when the forward vehicle detection unit detects the vehicle ahead, and switches the headlights to high beam when the forward vehicle detection unit does not detect the vehicle ahead. The headlamp control unit is characterized in that, in the first mode, if the speed determination unit determines that the vehicle's driving speed has fallen below a first speed, it transitions the control to the second mode.

2. It includes a brake state detection unit that detects whether or not the automatic brake is engaged, The speed determination unit further determines whether the travel speed has fallen below a second speed which is slower than the first speed. The headlamp control device according to claim 1, characterized in that the headlamp control unit switches the illumination of the headlamp to low beam when the speed determination unit determines that the vehicle's driving speed has fallen below the second speed, and the brake state detection unit determines that the automatic brake is not in operation.

3. The headlamp control device according to claim 2, characterized in that the headlamp control unit transitions to the first mode when the speed determination unit determines that the vehicle's travel speed exceeds a third speed which is faster than a first speed, and transitions to the second mode when the speed determination unit determines that the vehicle's travel speed exceeds a fourth speed which is faster than a second speed, and a predetermined speed difference is set between the first speed and the third speed, and between the second speed and the fourth speed.

4. A vehicle equipped with a headlamp control device according to any one of claims 1 to 3.

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