How the Lighting Assistant System works

Abstract

To provide an improved operating method for a lighting assistant system capable of reducing unnecessary display of error messages. The invention relates to a method for operating a lighting assistant system of a vehicle (1) which comprises at least a camera (2) for detecting oncoming or preceding traffic participants and a device for detecting the urban environment, in which the switching on of the main beam is suppressed when the vehicle is traveling in an urban environment. The method according to the invention is characterized in that when traveling in an urban environment, error messages relating to the limited field of view of the camera (2) are suppressed.

Description

[Technical field]

[0001] The present invention relates to a method for operating a lighting assistant system for a vehicle of the kind recited in the preamble of claim 1.

[0002] Lighting assistant systems for vehicles are known from the prior art. These systems are also known by the English name Intelligent Headlight Control (IHC). At the heart of these systems is a camera, usually facing forward in the direction of travel, which detects oncoming and preceding traffic participants and excludes them from the vehicle's high beam light distribution. This is done, for example, by simple dazzling from high beam to low beam, or, in more complex lighting systems, also by targeted dazzling of these traffic participants, in which case "gaps" are created in the high beam light distribution, for example in areas where oncoming traffic participants should not be dazzled.

[0003] Moreover, a typical lighting assistant system of this kind is operated in such a way that the high beam assistant is only used on suburban main roads, highways etc. and is kept off when passing through urban areas, i.e. urban traffic, villages, residential areas, industrial areas etc. Reference can be made in this connection, for example, to US Pat. No. 5,399,433, which discloses a method and a device for activating the urban lighting of a vehicle depending on the detected environment. Urban lighting as mentioned above means omitting the activation of the high beam in the lighting assistant. In the mentioned document, to detect the urban environment, the road lighting units are detected and based on the spatial distance between these road lighting units it is ascertained whether the vehicle is in an urban environment. Other methods for ascertaining the urban environment are likewise known from the prior art, for example based on the ambient lighting level or on the vehicle's satellite navigation system coordinates and a comparison with a corresponding map.

[0004] In practice, however, it may happen that the relevant surroundings sensor of the vehicle itself is functional, but is blocked, for example by dirt, so that the surroundings sensor can no longer be used for its intended purpose. In this connection, reference may be made, purely by way of example, to US Pat. No. 5,399,431 and to US Pat. No. 5,499,613, which corresponds substantially to this document, which disclose in contrast to other general prior art that such a blockage can be detected as such on the basis of the vehicle's motion pattern.

[0005] In practice, with regard to a lighting assistant system, such a sensor failure may be, for example, a limited field of view of the camera, due in particular to dirt, heavy rain, fogging of the glass through which the camera sees, etc. In practice, this leads to the generation of an error message informing the person driving the vehicle (the driver) that the lighting assistant system is temporarily not functioning, so that the driver is accordingly informed of the temporary unavailability of the assistant system. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] DE 10 2009 028 342 A1 [Patent Document 2] German Patent Application Publication No. 10 2018 220 114 A1 [Patent Document 3] German Patent Application Publication No. 10 2018 220 113 A1 Summary of the Invention [Problem to be solved by the invention]

[0007] The problem that the present invention aims to solve is to provide an improved method for operating a lighting assistant system according to the preamble of claim 1, which makes it possible to reduce unnecessary display of error messages. [Means for solving the problem]

[0008] This problem is solved according to the invention by a method for operating a lighting assistant system having claim 1, in particular the characterizing portion of claim 1. Advantageous embodiments and developments of the method according to the invention are evident from the dependent claims of this main claim.

[0009] In the method according to the invention, possible error messages regarding the limited field of view of the camera when driving in an urban environment are suppressed according to the invention. As already mentioned above, in most cases, a lighting assistant system of this kind needs to detect the urban environment in one way and / or the other way anyway. That is, the lighting assistant system recognizes that it is in an urban environment and therefore recognizes that the high beam, for which the assistant system is responsible, is not necessary with regard to increasing and / or decreasing the light and, if necessary, with regard to dazzling oncoming or preceding traffic participants. Instead, in an urban environment, driving is continuously performed with low beam.

[0010] However, it is a fact that many people who use vehicles start using them especially in urban environments. Especially in autumn and winter, when the temperature is relatively low and the vehicle is stationary, it occurs more frequently that the inside of the windshield fogs up relatively quickly, since the moisture of the vehicle settles on the generally cooler windshield. Many cameras used in particular for lighting assistant systems, but also for other purposes as necessary, are installed on the top of the windshield and point forward in the direction of travel. When the windshield fogs up, the field of view of this camera is limited. The same is true if the top of the windshield is still covered with ice or if ice or snow residues that were not carefully removed before the journey remain on the top of the windshield, which are generally not seen by the person driving the vehicle (the driver). It is precisely for this reason that when the journey starts in darkness in an urban environment, the lighting assistant system detects, after its first activation, that the field of view of the camera used by this system is obstructed or limited. However, this is not critical in a real urban environment. This is because in urban areas, the vehicle is driven with low beam anyway, and the assistance system is not used to increase or decrease the high beam in the intended range at all.

[0011] In such a situation, the method according to the invention accordingly suppresses this error message about the limited camera field of view, which has no effect on the actual use of the vehicle, thereby relieving the driver from unnecessary messages and thus allowing him to concentrate more on the traffic event than if a corresponding message such as "Camera field of view obstructed, high beam assistant deactivated" were displayed on the instrument panel. That is, the method according to the invention suppresses the error message about the limited camera field of view if a situation is detected in which high beams are not required anyway.

[0012] Furthermore, in another very advantageous embodiment according to the invention, if there is still an error message regarding the limited field of view of the camera when leaving the urban environment, this error message is displayed after a predefined time has elapsed since leaving the urban environment.

[0013] This advantageous development of the method according to the invention ensures that when leaving the urban environment, if the error message is still valid, i.e., for example, if the windshield is still appreciably fogged up, the display of this error message provides the driver with timely information in this situation in which high beam assistance is active, preferably by waiting a predefined time before displaying the error message, so that, on the one hand, the driver is not "inundated" with error messages near the border of the urban area, and, on the other hand, when driving on the periphery of the urban area, it is ensured that the error message is not displayed unnecessarily if the vehicle returns to the urban area in a very short time.

[0014] A further very advantageous embodiment of this concept then provides for the vehicle user to actively change the predetermined time, i.e. the suppression of warning messages after leaving the urban area becomes time-wise controllable by the vehicle user, for example by automatically setting a preferred time via a menu system, thus making it possible to adapt the vehicle and the potential display or suppression of such error messages to individual needs.

[0015] As already mentioned, the method may be particularly useful if a camera located behind the windshield, looking through the windshield in the direction of travel, is used for the lighting assistant system, but the method can also be used for other cameras, for example external cameras whose visibility may be impaired by snow, ice or a lot of water.

[0016] The device for detecting an urban environment can then use, in particular, the road lighting detected by the surroundings sensor, the illumination detected by the sensor, the vehicle speed, as well as the vehicle position determined by the satellite navigation system in comparison with a map showing the urban environment, to determine whether the vehicle is in an urban environment or not. In particular, by combining these possibilities with one another, a detection of the urban environment can be made as reliable as possible.

[0017] In this case, according to a very advantageous development, it can be provided that the urban environment is identified on the basis of road lighting, in particular by counting the number of detected street lights, and that the urban environment is then estimated on the basis of a predefined number of street lights, in particular a predefined number of street lights per distance unit.

[0018] That is, in this method, the street lights are counted and evaluated as a total number or number per distance unit. Then, above a certain number, it is determined that an urban environment is present. Additionally, this can be combined, for example, by an illuminance sensor, which in any case detects an urban environment or daylight at a certain illuminance and activates the lighting assistant system as a system in urban environment mode or, if it is daytime, deactivates the lighting assistant system accordingly. Furthermore, as another supplement, the result detected, in particular by the vehicle's sensor, can also be verified by determining the vehicle's position.

[0019] Further advantageous embodiments of the method according to the invention are evident from the detailed embodiment examples shown below with the aid of the figures. [Brief description of the drawings]

[0020] [Figure 1] 1 is a schematic diagram of a vehicle in an urban environment equipped with a camera and sensed by the camera; [Diagram 2] 3 is a flow chart of a possible embodiment of the method according to the invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] 1 shows a vehicle with the reference number 1, which is equipped with a multifunction camera 2 as shown, which is used on the one hand to detect the surroundings of the vehicle 1 and, on the other hand, can also be used for a so-called lighting assistant system.

[0022] In the scene shown in Fig. 1, three street lamps, each with the reference number 3, are shown by way of example only at the side of the road on which the vehicle is traveling. These are in the camera field of view, with the reference number 4, and are detected accordingly via the multifunction camera in a computing unit which is either within the multifunction camera or possibly external to this multifunction camera 2. Then, above a certain number, it is concluded that the vehicle is in an urban environment.

[0023] These or other possibilities for detecting the urban environment can be used in a known manner for the lighting assistant system, whereupon in an urban environment the lighting assistant system is limited to so-called low beam, and in the absence of an urban environment the high beam is also used accordingly, and leading or oncoming traffic participants are actively deglared, for example if pixel headlights or other suitable types of headlights are used, in order for the lighting assistant system to increase and decrease the high beam as required or to control the light distribution which allows targeted deglare (glare reduction) for individual traffic participants.

[0024] This part of the known lighting assistant system is shown primarily in the lower right area of ​​Figure 2, which shows the principle process steps, and which will be mentioned in more detail below.

[0025] Unlike the one shown in the schematic diagram of Fig. 1, the multifunctional camera 2 is typically positioned behind the windshield of the vehicle 1 and is directed forward in the direction of travel F. If the windshield is fogged up or if ice or snow remains in the upper area that the multifunctional camera 2 sees through the windshield and is not completely cleared, the field of view of the multifunctional camera 2 may be impaired. In prior art systems, an error message is generated in this case, which, in some circumstances, unnecessarily confuses the driver of the vehicle 1 and distracts him from the traffic incident.

[0026] The proposed method therefore has the following steps: in a first step, marked S100, the lighting assistant system is switched on, after which in step S101 a query is made as to whether the field of view of the multifunctional camera 2 is impaired. If not, then the conventional operation of the lighting assistant system is adopted. For this, as already mentioned at the beginning, it is necessary to detect whether the vehicle 1 is in an urban environment. Here, this is done by a query in step S102. If the vehicle is in an urban environment, then in step S103 a low beam only operation is realized, and the corresponding steps are always repeated when the process returns to the beginning. If the urban environment is left or the start of the lighting assistant system is outside the urban area, then instead of step S103, step S104 is performed, in which the high beam is activated, i.e. the lighting assistant system is actively used as a high beam assistant. As already mentioned above, steps S102 to S104 are basically implemented in the same way as in conventional lighting assistant systems, and query S102 is necessary in any case to decide whether to operate with low beam based on step S103 or with high beam based on step S104.

[0027] The method according to the invention is then used if the field of view is correspondingly impaired. This would generally result in an error message, independent of any other use of the lighting assistant system. According to the invention, in this branch with a "YES" in the inquiry in step S101, an inquiry is likewise carried out as to whether the vehicle 1 is in an urban environment. This step is now designated S202 and uses the database that is present for step S102 anyway. If this is not the case, i.e. if the vehicle is outside the urban environment, then in step S204 a well-known error message is generated, e.g. that the field of view of the camera 2 is impaired and therefore the high beam assistant cannot be used, and is output to the driver of the vehicle 1, e.g. on the multifunction display of the vehicle 1. However, since the vehicle 1 is often in an urban environment and the vehicle 1 starts driving in an urban environment with a high probability, the problem of fogged-up windshields generally occurs at the start of the drive. In this case, after the inquiry in step S202, a jump is made immediately to step S203, and operation with low beams that is valid for the urban environment is started. In the method according to the invention, error messages are omitted or actively suppressed, so that the driver of the vehicle 1 is not burdened with error messages that are unnecessary in this situation and are likewise not distracted from the traffic incident.

[0028] The process again loops back from step S204 to before the inquiry of step S101, so that it is possible to react accordingly to changing conditions, both with respect to the camera's view being compromised in step S101 and, for example, with respect to leaving the urban environment in either steps S102 or S202.

Claims

1. A method for operating a lighting assistant system of a vehicle (1) comprising at least a camera (2) for detecting oncoming or preceding traffic participants and a device for detecting an urban environment, in which the activation of the high beam is suppressed when the vehicle (1) travels in an urban environment, the method comprising the steps of: Error messages relating to the limited field of view of the camera (2) are suppressed when driving in the urban environment A method comprising:

2. If there is still an error message regarding the limited field of view of the camera (2) when the vehicle (1) leaves the urban environment, the error message is displayed after a predetermined time has elapsed since leaving the urban environment.

2. The method according to claim 1 .

3. The predetermined time period can be actively changed by a person using the vehicle (1).

3. The method according to claim 2 .

4. A camera (2) arranged behind the windshield of the vehicle (1) facing in the direction of travel (F) through the windshield is used for the lighting assistant system. The method according to any one of claims 1 to 3, characterized in that

5. The device for detecting the urban environment evaluates at least road lighting, illumination, vehicle speed and / or the position of the vehicle (1) detected by a satellite navigation system with respect to a map showing the urban environment, or a combination of these. The method according to any one of claims 1 to 4, characterized in that

6. When the field of view of the camera (2) is not restricted, the urban environment is identified based on the road lighting, and the number of detected street lights (3) is counted, and an urban environment is presumed when there is more than a predetermined absolute number of the street lights (3) or more than a predetermined number of the street lights (3) per distance unit.

6. The method according to claim 5 .

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