METHOD FOR ADJUSTING VEHICLE LIGHTING WHEN DRIVING ON A CONSTRUCTION SITE AND VEHICLE

Description

[0001] The invention relates to a method for adjusting vehicle lighting when driving on a construction site according to the type defined in more detail in the preamble of claim 1 and to a vehicle according to the type defined in more detail in the preamble of claim 8.

[0002] To enable safe operation of vehicles even in darkness, for example at night, vehicles are typically equipped with a lighting system. Such a lighting system illuminates the area around the vehicle, particularly the section of road ahead in the direction of travel. Depending on the situation, the brightness of the light emitted by the lighting system can be adjusted, as well as the direction in which the light is projected and the cross-sectional area it covers. Thus, vehicle headlights are typically operated with dipped beam in urban areas and with main beam in rural areas, provided there is no risk of dazzling other road users. This allows the driver to see further in the dark.By increasing not only the range of the light emitted by the lighting device but also its brightness, objects that are difficult to see can be perceived more clearly.

[0003] For this purpose, a driver can manually switch between low and high beams. Adaptive high-beam assist systems are also available, which automatically adjust the range and / or brightness of the light emitted by the headlights based on sensor signals. Modern vehicles use LEDs as light sources, particularly in the form of matrix headlights. Individual LEDs within the matrix headlight, also known as pixels, can be selectively controlled to block out areas of the light beam emitted by the matrix headlights. This allows, for example, the precise areas of the light beam where other road users are located to be excluded. In this way, high beams can be emitted simultaneously without dazzling other road users.Furthermore, it is known to shift the direction of propagation of light emitted by the lighting device, for example by moving a reflector and / or a lens of the lighting device. This makes it possible, for example, to implement adaptive cornering lights.

[0004] Driving through a construction zone at night presents a challenging traffic situation. In construction areas, the lane width is often reduced, requiring drivers to pay close attention to ensure safe operation. This is further complicated by poor visibility at night. A relatively high number of reflective objects in the environment, such as traffic signs and / or warning beacons, reflect light emitted by the vehicle's lights back towards the driver due to their retroreflective coating. Furthermore, the reflectivity of a newly laid road surface may be lower than that of an older surface, causing more light to be absorbed and making the traffic situation in the construction zone appear darker.This can make it difficult to recognize surrounding objects, road markings and exits, or to easily overlook them.

[0005] A method for operating a vehicle with a lighting device is known from DE 10 2011 014 455 A1. According to the method disclosed in the publication, the vehicle detects when it enters a construction site and automatically adjusts the light distribution emitted by the vehicle's headlights. A static cornering light is activated upon detection of a construction site, or a curve-shifting light is activated. Furthermore, the direction of propagation of the curve-shifting light or the static cornering light is directed laterally away from the vehicle to better illuminate the edge of the roadway within the construction zone. According to one embodiment of the invention disclosed in the publication, the emitted light output is also increased. This allows the driver to better perceive the edges of the roadway and / or objects located in the relevant area, thus enabling safer vehicle operation.To detect when a vehicle is entering a construction zone, camera images are analyzed and / or the vehicle's current position is compared with map data, where construction zones are marked. Additionally or alternatively, a vehicle's speed can also indicate the presence of a construction zone, as reduced speed limits typically apply in construction areas. Furthermore, a radio signal, for example via a vehicle-to-X communication interface, can be sent to the vehicle to inform it about the construction zone. However, a disadvantage of this method is that illuminating the edge of the roadway also reflects more light onto objects such as traffic signs and warning beacons, further increasing glare for the driver.

[0006] A vehicle lighting system is also known from DE 199 22 735 A1. This document describes an adjustment of the light emitted by the vehicle lighting system depending on current weather conditions and / or the condition of the road surface. This allows for adjustments to the direction and area of ​​the light emitted by the vehicle lighting system, as well as variations in the brightness and / or color of the emitted light. This brightens the surroundings, particularly in adverse weather conditions such as rain, fog, or snow. The lighting is also adjusted taking into account any moisture detected on the road surface. Individual headlights and / or components of the headlights, such as reflectors, can be swiveled, and / or auxiliary lights, such as fog lights, can be activated.The direction and / or area covered by the vehicle's lighting system are adjusted based on factors including the vehicle's steering angle, navigation data (from which the road's course is inferred), and camera images. This allows for the classification of weather conditions and the detection of other road users. The light emitted by the vehicle's lighting system is thus adapted to other road users to avoid dazzling them.

[0007] Furthermore, DE 10 2017 223 446 A1 discloses a lighting device for displaying animations to differentiate between various lighting functions. In this device, a vehicle can detect a construction site and increase the light intensity of its low beam headlights within the construction site. This approach is also known from DE 10 2011 014 455 A1, which describes a method and a device for operating a vehicle with a lighting device, and from DE 10 2006 048 503 A1, which describes a device for lateral guidance support for a road-bound vehicle.

[0008] The present invention is based on the objective of providing an improved method for adjusting vehicle lighting when driving through a construction site, whereby a vehicle driver is less dazzled when driving through a construction site and can still perceive a road marking that is otherwise difficult to see more easily.

[0009] According to the invention, this problem is solved by a method for adjusting vehicle lighting when driving on a construction site, comprising the features of claim 1, and by a vehicle comprising the features of claim 8. Advantageous embodiments and further developments are described in the dependent claims.

[0010] In a method for adjusting vehicle lighting when driving through a construction site of the type mentioned above, the light intensity with which the low beam is emitted is increased to a defined value when driving through the construction site. According to the invention, when an exit is detected, the focal point of the light pattern is shifted to an area of ​​the surroundings corresponding to the exit, or the area occupied by the light pattern is extended so that the area of ​​the surroundings corresponding to the exit is also illuminated, at least partially.

[0011] In darkness, especially at night, visual perception is limited in a construction zone. This is due, for example, to a new asphalt surface with poor light reflectivity and a comparatively high number of reflective objects in the surroundings, such as traffic signs and / or warning beacons. As a result, a driver may have difficulty recognizing relevant lane markings, making it harder to stay in their lane. Furthermore, the driver may have difficulty seeing surrounding objects and / or driving past an exit because they perceive it too late. This can reduce road safety. However, with the method according to the invention, sufficient visual perception can be achieved even when driving through a construction zone at night.This involves illuminating a relatively small area in the immediate vicinity in one direction of travel, with particularly bright light. The increased light intensity makes even difficult-to-see objects and road markings more clearly visible. By increasing only the light intensity of the lower beam, i.e., the dipped beam, the potential danger to the driver caused by light reflected from the headlights by surrounding objects is reduced.

[0012] Increasing the light intensity of the low beam can be achieved in various ways. For example, additional light sources and / or lamps can be activated, such as fog lights and / or previously deactivated LEDs or pixels of a matrix headlight. It is also conceivable to increase the power supplying the light sources. A blocking element can also be positioned in the beam path between the light source and the road surface, which, to increase the light intensity, is moved out of the beam path, at least partially. This increase in light intensity can be achieved in steps or continuously.

[0013] Driving through a construction zone refers to any point in time before, during, or after entering the zone. For example, the light intensity may increase at a predetermined distance before reaching a traffic sign indicating the construction zone, or it may increase only after the vehicle has traveled a specified distance within the zone. The light intensity may also increase depending on the distance traveled until the end of the construction zone and then return to its original level upon exiting the zone or after a specified time or distance. While the low beam intensity is being increased, the high beam may also be emitted by the vehicle's headlights.

[0014] According to the invention, when an exit is detected, the focal point of the photograph is shifted to a surrounding area corresponding to the exit, or the area covered by the photograph is expanded so that the surrounding area corresponding to the exit is at least partially illuminated. Due to structural limitations in a construction zone, exits are often displaced or have a reduced and / or narrower lane width. This makes exits in a construction zone particularly difficult to see. Especially at night, there is a significant risk that a driver will miss an exit. By illuminating the exits more brightly when driving through the construction zone, drivers are able to perceive them more easily. This reduces the risk of drivers unintentionally missing an exit.This can be achieved by swiveling a beam of light emitted from a vehicle's headlights to illuminate the construction site, and / or by switching on additional headlights or light sources to illuminate an area corresponding to the exit. Specifically, an exit is only brightened if the driver intends to take it. This can be determined, for example, by activating the turn signal. Furthermore, the driver's intention to take an exit can also be inferred by analyzing a planned route, such as one entered into the vehicle's navigation system. This prevents the unnecessary illumination of irrelevant exits. Thus, particularly convenient operation of the vehicle and its lighting when driving through a construction site is ensured.

[0015] A further advantageous development of the procedure involves reducing the light intensity with which the high beams are emitted when driving through the construction site, or deactivating the high beams altogether. As already mentioned, the driver is dazzled by light reflected from surrounding objects. By reducing the brightness of the high beams, or, even more advantageously, by deactivating them completely when driving through the construction site, the risk of the driver being dazzled by light reflected from the vehicle can also be reduced.

[0016] This allows for even safer operation of the vehicle when driving on a construction site at night.

[0017] According to a further advantageous embodiment of the procedure, the entry of vehicles onto the construction site is detected by at least one of the following methods: Evaluating at least one camera image generated by a vehicle camera; evaluating a sensor signal provided by a radar system; comparing a current vehicle position, in particular a vehicle position determined by means of a global navigation satellite system, with map data; evaluating a current vehicle speed; and / or evaluating a wireless construction site warning signal, in particular a construction site warning signal transmitted via a vehicle-to-X communication interface.

[0018] Using the methods mentioned, particularly reliable construction site detection is possible. Any camera, such as a multipurpose camera, can be used as the vehicle camera. This can be a mono or stereo camera. In particular, the vehicle camera can detect infrared light in addition to visible light, ensuring even more reliable image recognition in darkness. The radar system allows for reliable distance information to be acquired even in darkness. Especially at low speeds and close distances, an ultrasonic sensor system can be used for distance determination in addition to or as an alternative to a radar system. Distance determination using a laser scanner such as a lidar is also conceivable.Analogous to current technology, a construction zone can also be compared by comparing a vehicle's current position with construction zone positions recorded on maps. Driving into a construction zone can also be detected by a vehicle speed that is atypical for the currently driven road, for example, 80 km / h on a motorway. Furthermore, a wirelessly transmitted construction zone warning signal can indicate the presence of a construction zone, and this signal can also transmit additional information, such as the length of the construction zone.

[0019] A further advantageous embodiment of the method provides that the set value is modified depending on the road surface condition, in particular the type of road surface and / or any moisture detected on the road. By adjusting the low beam light intensity according to the road surface condition, even safer illumination of the construction site area can be ensured. Thus, depending on how strongly the road surface reflects light, the low beam light intensity can be increased. For example, if the road surface in a particular construction site has not been renewed, it will not absorb as much of the light emitted by the vehicle's headlights. In this case, the low beam light intensity does not need to be increased as much. This also applies to situations where the road surface is wet. For example, if it has rained or there is snow on the road, the reflectivity of the road surface increases.In this case, too, it is sufficient to increase the dipped beam headlights less. This also reduces the risk of light being reflected from the road towards surrounding objects such as traffic signs and / or warning beacons, thus further reducing the risk of glare for the driver.

[0020] According to a further advantageous embodiment of the method, sensor data from at least one vehicle camera and one laser scanner are fused to detect the road surface condition. Sensor fusion enables particularly reliable detection of the road surface condition. If a sensor system fails or delivers faulty sensor signals, false detections can be avoided by considering the sensor data provided by the functioning sensor. It is also possible to incorporate additional sensor systems into the sensor fusion. For example, sensor signals emitted by an ultrasonic or radar system can also be fused with the sensor data from the vehicle camera and the laser scanner to detect the road surface condition.

[0021] According to a further advantageous embodiment of the method, when at least one other road user is detected in the vicinity of the vehicle, the illumination of at least a defined area of ​​the photographic image, in particular the lower light field, is selectively excluded. This prevents unwanted glare for other road users. These other road users in the vicinity of the vehicle can be detected, for example, by evaluating camera images. They can also be detected by transmitting and receiving a signal via a vehicle-to-vehicle communication interface. Additionally or alternatively, a relative position or distance between the vehicle and the other road users can be determined, for example, using a distance detection system such as a laser scanner and / or a distance radar.This allows the system to calculate the areas of the light pattern, or the lower light field, that should be excluded from the light emitted by the vehicle's headlights. This is already a common feature of adaptive high-beam assist systems. However, if the road surface is wet, the moisture reflects the bright low beam, which can dazzle other road users approaching from that direction. Since the light intensity of the vehicle's low beam is specifically increased, other road users are then particularly affected by the glare.By evaluating the positional relationships of other road users to the vehicle and taking into account the reflection angles between the vehicle's headlights, the road surface, and other road users, it is possible to selectively exclude certain areas of the bright dipped beam projected onto the road, thus preventing other road users from being dazzled by light reflected from a wet road surface. This can further enhance road safety.

[0022] Preferably, at least one LED headlight, especially a matrix headlight, is used to project the light pattern. Generally, any vehicle headlight can be used for this purpose. This headlight can use, for example, incandescent, halogen, or xenon lamps as its light source. A laser is also a possible option. However, LEDs are particularly efficient, enabling the production of bright low beams with low energy consumption. Furthermore, a matrix headlight allows for particularly easy adjustment of the direction in which the light pattern is projected into the surroundings. This eliminates the need for moving parts, simplifying the headlight's design and making it more robust against vibrations. This, in turn, increases the reliability with which the light pattern is projected into the surroundings in the intended direction.

[0023] According to the invention, in a vehicle with at least one headlight, an environmental monitoring system, and a processing unit, the processing unit is configured to execute the method described above. The vehicle can be any type of vehicle, such as a car, truck, van, bus, or the like. One or more headlights can be used to emit the light image. Various sensor systems are suitable as environmental monitoring systems. For example, the vehicle's surroundings can be monitored using a camera, a radar system, a laser scanner, or the like. The processing unit can be any type of processing unit, such as a central on-board computer, a control unit of a vehicle subsystem, or a separate control computer specifically designed to carry out the method.Camera images can also be evaluated using artificial intelligence, for example in the form of an artificial neural network such as a Convolutional Neural Network.

[0024] Further advantageous embodiments of the method according to the invention also result from the exemplary embodiment, which is described in more detail below with reference to the figure.

[0025] The single figure depicts a vehicle driving through a construction site at night from the perspective of the driver.

[0026] The figure shows a vehicle 8 driving through a construction site 1 at night. To illuminate the area around the vehicle, the vehicle 8 is equipped with several headlights 2, hereinafter referred to as headlights 9. The headlights 9 emit light to create a light pattern 3. The light pattern 3 consists of an upper light field 3.1 and a lower light field 3.2, where the upper light field 3.1 corresponds to high beam and the lower light field 3.2 to low beam. In the figure, the headlights 9 emit light only to create the lower light field 3.2.

[0027] When driving through a construction zone 1, visual perception of the construction zone 1 is often limited because the road surface of a newly paved road 4 reflects light poorly, and numerous reflective objects in the vicinity, such as traffic signs 10 and warning beacons 11, are present in the construction zone 1. These reflect light emitted by the headlights 9 back towards the driver, causing glare. Visual perception of the construction zone 1 is improved by emitting low beams from the headlights 9 with a higher luminous intensity compared to typical low beams. The brighter low beam also illuminates the light-absorbing road surface and prevents glare for the driver by not illuminating reflective objects such as the traffic signs 10 and the warning beacons 11.This enables the driver to better perceive lane markings 12, thus making it easier for the driver to stay in their lane. This also improves driving comfort when driving through the construction zone.

[0028] It can happen that reflective areas are present on the road surface 4, for example in the form of wetness 5. Light emitted by the headlights 9 is reflected by the wetness 5 towards other road users 6, causing them to be dazzled. Since the low beam emitted using the method according to the invention is particularly bright, the other road users 6 are also strongly dazzled. To avoid this, individual areas 7 of the light pattern 3, preferably the lower light field 3.2, can be excluded. Thus, dazzling of the other road users 6 can be reliably avoided. To calculate the areas 7 to be excluded, camera images of the scene shown in the figure are generated and evaluated, for example. This allows the other road users 6 as well as the wetness 5 to be identified and positional relationships between the road users 6, the wetness 5 and the vehicle 8 to be determined.The headlights 9 calculate, which enables adaptive masking of areas 7. Additional sensor data can also be taken into account, for example, distance information generated by a radar or laser scanner system.

[0029] According to the invention, an exit in the area of ​​a construction site 1 is more brightly illuminated (not shown).

Claims

1. Method for adjusting vehicle lighting when driving on a construction site (1), a light image (3) cast into a surroundings by at least one vehicle headlight (2) being adjusted from an upper (3.1) light field referred to as a high beam and a lower light field (3.2) referred to as a low beam when driving on the construction site (1) is detected, by changing a light intensity with which the light image (3) is generated, the light intensity with which the low beam is emitted being increased to a specified value when driving on the construction site (1), characterized in that when an exit is detected, the focus of the light image is shifted to a surrounding region corresponding to the exit, or the area occupied by the light image is expanded so that the surrounding region corresponding to the exit is also illuminated at least in part.

2. Method according to claim 1, characterized in that the light intensity with which the high beam is emitted is reduced when driving on the construction site (1), or the high beam is deactivated.

3. Method according to either claim 1 or claim 2, characterized in that driving on the construction site (1) is detected by at least one of the following methods: evaluating at least one camera image generated by a vehicle camera; - evaluating a sensor signal provided by a radar system; - comparing a current vehicle position, in particular a vehicle position determined by means of a global navigation satellite system, with map material; - evaluating a current vehicle speed; and / or - evaluating a wireless construction site warning signal, in particular a construction site warning signal transmitted via a vehicle-to-X communication interface.

4. Method according to any of claims 1 to 3, characterized in that the specified value is changed depending on a road condition, in particular a road surface and / or wetness (5) detected on the road (4).

5. Method according to claim 4, characterized in that in order to detect the road condition, sensor data from at least one vehicle camera and a laser scanner are fused.

6. Method according to any of claims 1 to 5, characterized in that upon detection of at least one further road user (6) located in the vehicle surroundings, illumination of at least one specified region (7) of the light image (3), in particular of the lower light field (3.2), is omitted in a targeted manner.

7. Method according to any of claims 1 to 6, characterized in that at least one LED headlight, in particular a matrix headlight, is used to emit the light image (3).

8. Vehicle (8) comprising at least one headlight (9), a surroundings monitoring system and a computing unit, characterized in that the computing unit is configured to carry out a method according to any of claims 1 to 7.