Method for operating at least one vehicle headlamp and vehicle

Abstract

The present invention relates to a method for operating at least one vehicle headlight (1), wherein the vehicle headlight (1) is switched between a low-light basic illumination mode and a high-light basic illumination mode according to a control signal, and wherein the light field (5) emitted by the vehicle headlight (1) under the high-light basic illumination mode is dimmed at least regionally and / or brightened regionally by turning on at least one additional light source according to the control signal. The method according to the invention is characterized by at least the following steps: - operating the vehicle headlights (1) and turning on the auxiliary light source; - when it is necessary to darken at least one area (5.3) of the light field (5) or switch the vehicle headlights (1) to a low-light basic lighting mode: deactivating the auxiliary light source; - the computing unit (4) checks the sensor signals to determine whether it is still necessary to darken the light field (5) at least regionally or switch the vehicle headlights (1) to a low-light basic lighting mode; - if so: darken at least one area (5.3) of the light field (5) or switch the vehicle headlights (1) to a low-light basic lighting mode; or - if not, operate the vehicle headlights (1) in a high-light basic lighting mode and turn on the auxiliary light source.

Description

Technical Field

[0001] The present invention relates to a method for operating at least one vehicle headlight and a vehicle for performing the method. Background Technology

[0002] Vehicles typically have headlights as a form of illumination to light their surroundings, enabling them to operate safely in darkness, such as at night. These headlights often operate in different modes, emitting light with varying characteristics. This involves adjusting the headlight beam's range and / or brightness. If there are other road users and / or vehicles traveling through urban areas in front of the vehicle, the headlights are typically operated at low beam to avoid dazzling them. On rural roads or highways, if there are no other road users in front, the headlights can be operated at high beam to allow the driver to see further in the dark.

[0003] Furthermore, so-called high-beam assist devices are known that automatically adjust the illumination distance and / or brightness of the headlights based on road users identified by an environmental monitoring system. For example, they can automatically switch from high beams to low beams, or dim or extinguish the headlight cone in areas occupied by other road users. This prevents glare to other road users even when high beams are on. So-called matrix or pixel headlights are particularly suitable as vehicle headlights because they can produce specific light patterns very easily.

[0004] Furthermore, it is known that vehicle headlights, in addition to the basic lighting components, also include supplementary lighting devices that can produce a particularly long and bright beam. Such a beam is also known as a high beam spot, produced by focusing relatively bright light onto a particularly small area. What may occur here is that the high beam assist device, when controlling a vehicle headlight with a high beam, disproportionately and unnecessarily dims the high beam emitted by the vehicle headlights due to misdetection. In addition to the vehicle headlights and the controller for controlling the headlights, the high beam assist device also includes optical sensors for monitoring the vehicle's surroundings. If the optical sensors receive light intensity from the surrounding environment exceeding a specified value, it indicates an oncoming vehicle. In this case, the high beam emitted by the vehicle headlights must be dimmed to avoid dazzling potential oncoming road users. However, what may occur here is not actually an oncoming vehicle with its headlights on, but rather a static or dynamic surrounding object that reflects the light emitted by the vehicle headlights back towards the vehicle. In this case, dimming is unnecessary. If a reflective object (such as the reflector on a road guide post or the crossbar of a barrier) is illuminated by a high beam, the object will reflect a particularly large amount of light in the direction of the vehicle emitting the high beam, so the reflective object is often mistaken for a road user emitting the light.

[0005] To avoid such false detections, DE 10 2011 081 428 A1 discloses a method for determining the object category of objects that emit and / or reflect light onto a vehicle. Here, a high-beam assist device in the vehicle includes at least two cameras offset from each other as optical sensors. These cameras may also be offset from each other by only a relatively small margin, for example, stereo cameras. Using these two cameras, light emitted or reflected by surrounding objects is recorded from different perspectives, thereby enabling the differentiation between self-illuminating objects (e.g., oncoming road users) and light-reflecting objects (e.g., reflectors). This reduces the false detection rate of the high-beam assist device misidentifying oncoming road users and thus dimming the lights. The document also states that when a road user is indeed identified, in addition to dimming the high beams, the additional lighting of the vehicle's headlights can be turned off. However, at least two cameras for monitoring the surrounding environment are required to perform the method disclosed in this document. Summary of the Invention

[0006] The object of the present invention is to provide an improved method for operating at least one vehicle headlight having an additional light source to produce a long-range and bright high beam, by means of which unnecessary dimming of the vehicle headlight can be reliably avoided or at least reduced, even when using a high beam assist device that uses only an optical sensor.

[0007] A method for operating at least one vehicle headlight of the type described above, wherein the vehicle headlight is adapted to emit a light field that can be enhanced by turning on at least one additional light source, according to the invention, wherein at least the following steps are performed in the method:

[0008] - Enable the vehicle's headlights to operate in the basic high-beam lighting mode and turn on the auxiliary light source;

[0009] - When it is determined through evaluation of sensor signals that it is necessary to darken at least one area of ​​the light field or switch the vehicle headlights to a low-light basic lighting mode: disable the auxiliary light source;

[0010] - The computing unit checks the sensor signals to determine whether it is still necessary to dim the light field at least regionally or switch the vehicle headlights to a low-light basic lighting mode.

[0011] - If this is the case: then darken at least one area of ​​the light field or switch the vehicle's headlights to a low-light basic illumination mode; or

[0012] - If this is not the case: then operate the vehicle headlights in the basic high-beam lighting mode and turn on the auxiliary light source.

[0013] If a vehicle's headlights, when the auxiliary light source is turned on, illuminate a particularly reflective surrounding object, that object will also reflect light back towards the vehicle with a relatively high intensity. This increases the likelihood of confusing the surrounding object with other road users, as the object appears to the optical sensor as a self-illuminating road user due to the high light intensity. In this case, the light field emitted by the vehicle's headlights should be dimmed at least regionally, or the headlights should be switched to a low-light basic illumination mode. However, if the auxiliary light source is not operated, the likelihood of the surrounding object being mistakenly identified as another road user is reduced, as the object now reflects too little light to be considered a self-illuminating road user. If the sensor signal is re-examined by the computing unit after the auxiliary light source is turned off, the distinction between road users and surrounding objects can be made more reliably. If it is indeed another road user, the light field emitted by the vehicle's headlights should be dimmed at least regionally, or the headlights should be switched to a low-light basic illumination mode. However, if the processing unit determines it is a surrounding object, the auxiliary light source can be safely turned on again. To implement the method according to the invention, no structural changes to the high beam assist device are required, and therefore the method according to the invention can also be used particularly simply in existing vehicles.

[0014] The basic lighting mode for low light can be, for example, low beam headlights, while the basic lighting mode for high light can be high beam headlights.

[0015] Various sensors can be used as optical sensors. For example, a brightness sensor could be used. However, an advantageous improvement to this method is that the optical sensor is at least one camera. The camera generates camera images, which are evaluated by a computing unit. This allows for the acquisition of a particularly wide range of information. Since modern vehicles are typically equipped with cameras, there is no need to install additional hardware on the vehicle. The camera can be any type of camera, such as a multi-purpose camera. It can be implemented as a monocular camera or a stereo camera and capture light in the visible and / or infrared spectra. In particular, using a camera adapted to capture infrared light allows for particularly reliable imaging of surrounding objects in the dark.

[0016] According to another advantageous design of this method, the necessity to darken at least one area of ​​the light field or switch the vehicle's headlights to a low-light basic illumination mode is determined by identifying at least one object to be shaded in at least one camera image generated by the camera. The object to be shaded is, for example, another road user, such as a cyclist, passenger car, truck, or any road vehicle traveling in the opposite direction of the vehicle. This other road user may also be traveling in the same direction as the vehicle. It can also cause glare to other road users traveling in the same direction from behind, as vehicles typically have side mirrors and interior mirrors that direct the light emitted by the vehicle toward the driver of the vehicle traveling in front, which can cause glare. The object to be shaded can also be a building. For example, light emitted by the vehicle may enter a building through a window, which can disturb people inside the building.

[0017] Another advantageous design of this method involves identifying objects to be shaded in the camera image, where at least a portion of the camera image is covered by light with an intensity exceeding a specified limit. Because other road users typically emit light themselves in darkness, especially at night, they can be identified as such when a luminous object is detected. In this case, the luminous object is classified as an object to be shaded, and the vehicle's headlights are dimmed. For this purpose, a limit is specified for the luminous intensity of light emitted by surrounding objects; this limit must be exceeded to identify the surrounding object as either another road user or an object to be shaded. This allows, for example, the differentiation of luminous objects in the surrounding environment (e.g., construction site markers or streetlights) from oncoming vehicles.

[0018] Artificial intelligence, particularly artificial neural networks, is preferred for camera image evaluation. Camera images can be evaluated reliably by using artificial intelligence, especially artificial neural networks (such as convolutional neural networks). This reduces the false detection rate, which misidentifies features in camera images.

[0019] In a vehicle having at least one headlight, a computing unit, and an optical sensor, according to the invention, the computing unit is adapted to perform the aforementioned method. The vehicle can be any vehicle, such as a passenger car, truck, van, bus, etc. A separate computing unit can be provided to perform the method. However, it can also be a central on-board computer or a controller for a vehicle subsystem. Similarly, any vehicle headlight is involved. It can have multiple light sources for emitting basic illumination. The vehicle headlight can have any lamp as an illumination device, such as an incandescent lamp, halogen lamp, xenon lamp, fluorescent tube, laser, or LED. In particular, the vehicle headlight is a so-called matrix or pixel headlight. The vehicle headlight can include one or more reflectors, mirrors, lenses, and / or prisms. They can be controlled by means of actuators, such as moving them. Thus, for example, the direction of light propagation of the light field emitted by the vehicle headlight can be controlled. By selectively turning individual illumination devices on or off, the brightness of the light field can be changed and / or individual areas of the light field can be selectively darkened. With the help of an additional light source, vehicle headlights can emit what is known as a high beam, which can illuminate environmental areas that are particularly far from the vehicle with exceptionally high brightness. Attached Figure Description

[0020] Other advantageous designs of the method and vehicle according to the invention are also given by way of embodiments described in more detail below with reference to the accompanying drawings.

[0021] In the attached diagram:

[0022] Figure 1 shows a schematic diagram illustrating the known operating principle of the high beam assist device; and

[0023] Figure 2 A schematic diagram illustrating the operating principle of a high beam assist device according to the method of the present invention is shown. Detailed Implementation

[0024] Figure 1a) shows a vehicle 2, which has an optical sensor 3, a computing unit 4, and two vehicle headlights 1. The vehicle headlights 1 project a light field 5 onto the surrounding area in front of the vehicle 2 in the direction of travel F. In the illustration, for spatial reasons, the light field 5 originates from the center of the vehicle rather than from the vehicle headlights 1. The light field 5 consists of two regions 5.1 and 5.2. Region 5.2 is superimposed on region 5.1. In region 5.1, the vehicle headlights 1 project light (e.g., high beam) into the surrounding environment according to a basic illumination pattern of strong light. One or both vehicle headlights 1 include an additional light source, by means of which a particularly bright and long-range light is projected into the environment according to region 5.2. This light is also referred to as a high beam. Thus, the distant environmental area in front of the vehicle 2 can be illuminated particularly brightly, enabling the vehicle 2 to be operated comfortably and safely by the driver at night. The optical sensor 3, in the form of a camera, is used to monitor the environment. Here, the sensor signal generated by the optical sensor 3 is evaluated by the computing unit 4 to identify potential objects 6 or other road users. Based on the detected object 6 or road user, the computing unit 4 outputs a control signal to control the vehicle headlights 1, thereby changing the light characteristics of the light field 5. Thus, when another road user is identified, especially a road user approaching the vehicle 2, area 5.3 of the light field 5 is turned off or switched from a strong light basic illumination mode to a weak light basic illumination mode to avoid dazzling oncoming road users.

[0025] In the example of Figure 1a), the high beam, i.e., region 5.2 of the light field 5, illuminates an object 6.1 (e.g., a reflector on a guide post) that reflects the high beam back to the direction of vehicle 2. The calculation unit 4 then detects a particularly high light intensity in the camera image generated by the camera and thereby identifies the approach of an oncoming road user. Accordingly, the calculation unit 4 outputs a control signal to dim region 5.3 of the light field 5. As a result, object 6.1 is excluded from the illumination of vehicle 2, or the vehicle headlights 1 are switched to a low-light basic illumination mode, thus illuminating region 5.4, which is smaller than region 5.1, with particularly low brightness.

[0026] However, since object 6.1 is not an oncoming road user but a guide post, it is not necessary to darken area 5.3 or operate vehicle headlights 1 in a low-beam basic lighting mode. Figure 2 The process of dimming or shading a vehicle headlight 1 by means of the method according to the invention is shown. Figure 2 a) corresponds to the traffic situation in Figure 1a). If an object requiring shading is detected in the camera image, i.e., an oncoming road user, the high beam, i.e., the auxiliary light source, is turned off first. This is in Figure 2As shown in b). Here, the vehicle headlight 1 illuminates only area 5.1 according to the basic illumination pattern of strong light. At this time, the object 6.1 reflects the light emitted by the vehicle headlight 1 less intensely towards the vehicle 2, thereby allowing the calculation unit 4 to reliably determine the oncoming road user or object 6 based on the new evaluation of the camera image. Figure 2 c1) and 2c2) adjust the light field region 5.3 accordingly based on the re-evaluated camera image, either by darkening it, operating the vehicle headlight 1 in a low-light basic illumination mode, or by reactivating the high beam. This avoids unnecessary dimming or shading of the vehicle headlight 1, thereby improving driving comfort when using the vehicle 2 in the dark.

Claims

1. Method for operating at least one vehicle headlight (1), wherein a vehicle (2) monitors its surroundings by means of at least one optical sensor (3) and evaluates sensor signals generated by the optical sensor (3) by means of a computing unit (4) to generate a control signal, and in accordance with the control signal switches the vehicle headlight (1) between a basic lighting mode in weak light and a basic lighting mode in strong light, and wherein in accordance with the control signal at least regionally darkens and / or regionally brightens by switching on at least one additional light source a light field (5) emitted by the vehicle headlight (1) in the basic lighting mode in strong light, characterized at least by the following steps: - operating the vehicle headlight (1) in the basic lighting mode in strong light and switching on the additional light source; - when it is determined by evaluation of the sensor signals that it is necessary to darken at least one region (5.3) of the light field (5) or to switch the vehicle headlight (1) to the basic lighting mode in weak light: deactivating the additional light source; - checking the sensor signals by the computing unit (4) to determine whether it is still necessary to darken at least regionally the light field (5) or to switch the vehicle headlight (1) to the basic lighting mode in weak light; - if this is the case: darkening at least one region (5.3) of the light field (5) or switching the vehicle headlight (1) to the basic lighting mode in weak light; or - if this is not the case: operating the vehicle headlight (1) in the basic lighting mode in strong light and switching on the additional light source.

2. Method according to claim 1, characterized in that at least one camera is used as the optical sensor (3).

3. Method according to claim 2, characterized in that the necessity to darken at least one region (5.3) of the light field (5) or to switch the vehicle headlight (1) to the basic lighting mode in weak light is determined by recognizing at least one object (6) to be shaded in at least one camera image generated by the camera.

4. Method according to claim 3, characterized in that an object (6) to be shaded is thus recognized in a camera image, i.e. at least one partial region of the camera image is covered by light with a light intensity above a specified limit value.

5. Method according to any one of claims 2 to 4, characterized in that camera images are evaluated using artificial intelligence.

6. Method according to claim 5, characterized in that camera images are evaluated using an artificial neural network.

7. Vehicle (2) with at least one vehicle headlight (1), a computing unit (4) and an optical sensor (3), characterized in that the computing unit (4) is adapted to carry out a method according to any one of claims 1 to 6. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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