Method of reporting glare caused by a vehicle's headlight system and determining misalignment thereof

Abstract

A method for reporting a glare caused by a headlight system of an oncoming vehicle is provided, the method by means of a message of a detected glare generated by a vehicle being dazzled, wherein the message has information about the position of the vehicle being dazzled at the time of the detected glare. In addition, a method for determining a misalignment of a headlight system of a vehicle causing a glare is provided, the method based on this message and by comparing a first intersection between a trajectory of an oncoming vehicle being dazzled and a light field generated by a headlight system of a vehicle causing a glare and a second intersection between a trajectory of an oncoming vehicle being dazzled and a model of the light field generated by the headlight system of the vehicle causing a glare, the model being saved in the vehicle system.

Description

TECHNICAL FIELD

[0001] The invention relates to a method for reporting glare caused by a headlight system of an oncoming vehicle and a method for determining misalignment of a headlight system of a vehicle. BACKGROUND

[0002] Today, almost exclusively, in high-end vehicles, LED-based active headlamps, so-called LED matrix headlamps, are installed. In LED matrix headlamps, assemblies formed by LEDs arranged next to each other and on top of each other on a circuit board are provided. LED matrix headlamps are referred to as active, because their light emission can be optimally adapted to the respective driving situation. By intelligently controlling the LED matrix of the headlamps, a multitude of functions can be realized by means of a dynamically generated light field, significantly improving driving comfort and driving safety. A particularly prominent and sophisticated function is not only to segmentally shade oncoming traffic in order to avoid glare for oncoming vehicles, but at the same time to also enhance the illumination of the own lane. As a further function, strongly reflective traffic signs can be recognized by means of a camera and selectively faded or illuminated with lower intensity. The driver's line of sight is thus purposefully diverted and overstimulation is prevented.

[0003] With the increasing number of individually controllable LEDs in LED matrix headlamps, which is currently already in the three-digit range, it is possible to segmentally shade recognized traffic participants with increasing precision, whereby a better illumination of the driving environment can be achieved. However, if a mechanical change occurs in the headlamps or the vehicle body, that is, a misalignment with respect to its intended position is ultimately caused, it is still possible to dazzle other traffic participants. Since such misalignments can mostly only be corrected in a professional workshop by means of a re-setting of the light, a loss in driving safety is to be expected when continuing to drive, since the driving environment cannot be optimally illuminated.

[0004] Methods to address this problem in the prior art are known. For example, document AT 519976 B1 discloses a method for operating a headlight of a motor vehicle, which illuminates a region in front of the motor vehicle in the form of a defined light distribution, wherein an oncoming motor vehicle is detected and this region of the light distribution is dimmed, wherein the oncoming motor vehicle communicates with the motor vehicle causing the glare by means of a modulation of its light field and thereby signals the occurrence of the glare.

[0005] Document DE 10 2012 203 214 A1 discloses a method and a device for determining glare of a driver of a motor vehicle, wherein the glare is determined by means of an optical light sensor when a predetermined glare indicator is met and a warning signal is sent to another motor vehicle.

[0006] The document DE 10 2013 222 628 A1 discloses a method for detecting a misalignment of a headlight of a motor vehicle, wherein light of an oncoming motor vehicle is detected and its position is ascertained, wherein it is also ascertained whether the detected light is a flashing signal of another vehicle and whether the other vehicle is located in the environmental region illuminated by the headlight of the vehicle at the time point of the flashing signal, wherein the flashing signal indicates a misalignment of the headlight, which is corrected on the basis of the flashing signal.

[0007] The method known from the prior art has the disadvantage, however, that in the case of only one sensor, for example one driver assistance camera, the direction of the misalignment of the headlight cannot be identified. Only the fact that the headlight has been dazzled can be detected and thus only theoretically that there is a misalignment of the headlight. The safety region or the dimmed region in the light field generated is enlarged in the case of a misalignment without directional information about the misalignment, however, which must be done in both directions of the potentially dazzled vehicle, resulting in a suboptimal illumination of the vehicle environment. SUMMARY

[0008] Starting from the problems described above and the prior art outlined, the object of the present application can be seen as to provide a method by means of which the dazzling of another road user caused by a misalignment of the headlight of the dazzling vehicle can be detected and also optimally eliminated.

[0009] This object is achieved by means of the method and the device described in the following embodiments.

[0010] The present application is based on the recognition that by means of a single sensor, such as a driver assistance camera (FAS, hereinafter vehicle camera), it is possible to determine in which direction the headlight system of the oncoming vehicle causing the dazzling is shifted. For this purpose, the dazzled vehicle can transmit information about the dazzling process to the further oncoming vehicle causing the dazzling by means of car-to-car communication (also referred to as C2C communication). In the vehicle causing the dazzling, the misalignment of the headlight can be derived from the transmitted information and stored in a control device in order to be applied for future anti-dazzling. In addition, the offset required to correct the misalignment can be set anew by the tester in the professional workshop at the next headlight adjustment.

[0011] It is to be noted that the headlight or the headlight system mentioned in the context of the description of the method and the device of the present application is an LED matrix headlight. It is further to be noted that in the context of the present application, car-to-car communication (which can also be referred to as vehicle-to-vehicle (V2V) communication) means a direct communication between vehicles for the purpose of exchanging information and data, the goal of which is to report critical and dangerous traffic situations to the driver in advance.

[0012] According to an aspect of the present application, a method for reporting a glare caused by a headlight system of an oncoming vehicle is provided, wherein the method is performed in the vehicle being dazzled. In a first step, a glare in the vehicle being dazzled caused by the oncoming vehicle causing the glare is detected by means of an optical sensor in the vehicle being dazzled. The optical sensor can in particular be a vehicle camera. The glare is detected when the optical sensor crosses a light-dark border or a dark-light border produced by the headlight system of the vehicle causing the glare. In other words, a reference point for the glare occurring can be set when the optical sensor enters or leaves the light field of the vehicle causing the glare. In addition, a minimum time duration can be determined which the illumination process determined by the optical sensor has to last in order to be classified as a glare process. Thereby, it can be prevented that illumination processes from the environment randomly associated with the oncoming vehicle are falsely classified as glare processes caused by the oncoming vehicle. The minimum time duration can depend on the speed and can be in the range of tens of microseconds to seconds.

[0013] In a next step, the method of the present application comprises generating a message that the glare has been detected, wherein the message has information about the position of the vehicle being dazzled when the glare was detected. The position can be the vehicle position acquired by means of GPS. The generated message can correspond to a system internal message within the on-board system of the vehicle being dazzled.

[0014] In a next step, the method of the present application comprises transmitting the message to the vehicle causing the glare by means of a wireless transmission module of the vehicle being dazzled. The transmitted message can in particular be a message within a data radio system designed for C2C communication and thus working on the basis of broadcast messages. The advantage is that it can be transmitted and received in a infrastructure-less manner on the one hand and not only be directed to one or more dedicated receivers but also, in theory, be received by all participants in the local environment of the transmitter.

[0015] According to a further embodiment of the method of the present application, the message can contain an identity identifier of the vehicle being dazzled. Thereby, the vehicle causing the glare receiving the message derives information about the optical sensor of the vehicle being dazzled and possibly more accurately learns about the misalignment of the headlight of the vehicle causing the glare. These information can already be contained in the message itself or be retrieved by the vehicle receiving the message from a database.

[0016] According to a further embodiment of the method according to the application, the message can contain information about the time of the detected glare. Thereby, the reference point chosen for the determination of the glare is provided with a time stamp, which can be used by the vehicle causing the glare to improve the accuracy when calculating the misalignment of its headlamps.

[0017] According to a further aspect of the application, a method for determining a misalignment of a headlamp system of a vehicle causing glare is provided, which is implemented in the vehicle causing the glare. This method can be based on the previously explained method for reporting glare caused by a headlamp system of an oncoming vehicle according to the application.

[0018] In a first step, the method for determining a misalignment of a headlamp system of a vehicle causing glare comprises receiving a message from an oncoming vehicle that the oncoming vehicle has detected glare by means of a wireless receiving module of the vehicle causing the glare, wherein the message contains information about the position of the dazzled vehicle at the time of the detected glare situation. The message can be the message already mentioned previously, which has been explained in the context of the method for reporting glare caused by a headlamp system of an oncoming vehicle already explained.

[0019] In a further step, the method according to the application can comprise determining a trajectory of the dazzled oncoming vehicle by means of a vehicle camera of the vehicle causing the glare. For this purpose, the (dazzled) oncoming vehicle can be identified in the image of the vehicle camera and its trajectory can be determined with respect to a reference point chosen in a conventional manner (e.g. the midpoint between the headlamps, the left or right headlamp, the midpoint of the upper edge of the front windshield, etc.). Here, the acquisition of the trajectory can take place on photos of the vehicle camera already taken before the reception of the message, which have been stored in a cache, preferably provided with a time stamp. Thereby, the restriction to only use image material of the vehicle camera that has been recorded by the vehicle camera since the time of the reception of the message from the dazzled vehicle can be circumvented. This can be advantageous for the accuracy and robustness of the calculation algorithm, especially in cases where certain positions of the dazzled vehicle in the field of view of the vehicle camera are not visible since the time of the reception of the message by the vehicle causing the glare, e.g. because it is obscured by an object located at the edge of the road or a passing vehicle and thus can be detected less well or with a time delay.

[0020] In a further step, the method of the application comprises determining a first intersection between the trajectory of the oncoming vehicle that is dazzled and the light field generated by the headlamp system of the vehicle that is causing the dazzle. For this purpose, the image material received by the vehicle camera is correspondingly processed and the overlap of the dazzled vehicle identified therein and the light field generated by the vehicle that is causing the dazzle is analyzed. The first intersection here corresponds to the real intersection between the trajectory of the oncoming vehicle and the section boundary of the light field generated by the vehicle that is causing the dazzle. The section boundary of the light field can refer to a bright-dark transition or a dark-bright transition within the generated light field, in particular the transition between the light field portion that is dimmed as a result of the corresponding LEDs in the matrix being switched off and the remaining active or light-filled light field portion.

[0021] In a further step, the method of the application comprises acquiring a second intersection between the trajectory of the oncoming vehicle that is dazzled and a model of the light field generated by the headlamp system of the vehicle that is causing the dazzle, which is stored in the vehicle system. Here, the model of the light field generated by the headlamp system of the vehicle that is causing the dazzle can correspond to the light field actually generated at the time of the dazzle. For this purpose, the control device of the headlamp system can have a memory in which a history of the control data of the headlamp over a predetermined period of time, for example a few seconds to tens of seconds, is stored. The second intersection corresponds to the expected intersection between the trajectory of the oncoming vehicle and the corresponding section boundary of the light field generated by the vehicle that is causing the dazzle in the case of a correctly set headlamp.

[0022] In a further step, the method comprises calculating the mispositioning of the headlamp system of the vehicle that is causing the dazzle by comparing the first intersection with the second intersection. From the calculated mispositioning, in particular a bias can be acquired that has to be applied in the generation of the light field in order to generate the generated light field and in particular the dynamically generated dimmed region at its correct position.

[0023] Overall, the second aspect of the application is about determining the mispositioning direction of the headlamp by means of a single optical sensor. For this purpose, the vehicle that is dazzled sometimes sends information to the vehicle that is causing the dazzle from when it is spatially and / or temporally dazzled or no longer dazzled. The vehicle that is causing the dazzle can reconstruct the real position of the section boundary in its light field from this information and compare it with the expected position of the system boundary stored in the system. It is emphasized here that not only the direction but also the amount of the shift can be acquired here. On this basis, the vehicle that is causing the dazzle can purposefully set a bias for the anti-dazzle that is derived from the acquired amount of the shift and thus purposefully correct this light function. Iterative enlargement of the dimmed or safety region on both sides of the vehicle that is dazzled can be dispensed with.

[0024] According to a further embodiment of the method according to the application, the position of the dazzled vehicle at which the dazzle is detected by the dazzled vehicle can correspond to the position at which the optical sensor crosses a light-dark border or a dark-light border produced by the headlamp system of the dazzle-causing vehicle. In other words, the method according to the application can use the segment border of the light field produced by the dazzle-causing vehicle, which is inside or outside the lane.

[0025] According to a further embodiment of the method according to the application, the method can also comprise correcting the light field produced by the headlamp system on the basis of the calculated misalignment. Such a correction can in particular comprise applying a Versatz (offset) for correction to the light field produced by means of the headlamp.

[0026] According to a further embodiment of the method according to the application, the message can contain information on the time of the dazzle detected by the dazzled vehicle. The reference point selected for the determination of the dazzle, i.e. the passage of the optical sensor through the light-dark border or the dark-light border of the light field, can thus be time-stamped, as already mentioned.

[0027] According to a further embodiment of the method according to the application, the message can contain an identity identifier of the dazzled vehicle. Reference can also be made in this respect to the method for reporting the dazzle caused by the headlamp system of the oncoming vehicle causing the dazzle explained previously.

[0028] In a further aspect of the application, a dazzle detection module for a vehicle is provided, which is coupled with a wireless transceiver module and a vehicle camera and is adapted for carrying out the method for reporting the dazzle explained previously and the method for determining the misalignment of the headlamp system explained previously. The dazzle detection module can be implemented within the on-board system of the vehicle or form a separate computing module. In addition, the dazzle detection module can be coupled with a control device of the headlamp system of the vehicle or with a functional module connected correspondingly upstream thereof in order to be able to transmit the acquired offset to the control device. The dazzle detection module according to the application can carry out the method on the side of the dazzled vehicle and the method on the side of the dazzle-causing vehicle, as the case can be.

[0029] In a further aspect of the application, a method for determining the misalignment of the headlamp system of a dazzle-causing vehicle on the basis of inter-vehicle communication is provided, wherein the method according to the application for reporting the dazzle caused by the headlamp system of the oncoming vehicle causing the dazzle is first carried out as a first sub-method and the method for determining the misalignment of the headlamp system of the dazzle-causing vehicle is subsequently carried out as a second sub-method on this basis. The first sub-method can be used as a trigger mechanism for carrying out the second sub-method here. BRIEF DESCRIPTION OF DRAWINGS

[0030] It is self-evident that the features mentioned above as well as the features still to be described in the following description can be used not only in the combinations given in each case, but also in other combinations or on their own, without leaving the scope of the present application.

[0031] Further advantages and design solutions of the present application result from the whole of the description and the drawings.

[0032] Figure 1 A driving situation is shown in which the light field of the first vehicle does not dazzle the oncoming vehicle.

[0033] Figure 2 A driving situation is shown in which the light field of the first vehicle dazzles the oncoming vehicle.

[0034] Figures 3A to 3C A schematic diagram of the driving situation shown in Figure 1 and Figure 2 is shown.

[0035] Figure 4 A flowchart is shown which shows embodiments of the two methods of the present application in a form related to each other. DETAILED DESCRIPTION

[0036] A driving situation is shown in Figure 1 and Figure 2 in which a first vehicle 1 coming from the left on a lane F approaches a vehicle 4 coming from the right, which first vehicle generates a first light field 2 by means of its headlamps. In order not to dazzle the vehicle 4 coming from the right, the headlamps of the first vehicle 1 are controlled in such a way that a darkened area 3, also referred to as a safety area, is generated in the light field 2. In other words, by means of the vehicle camera of the first vehicle 1, which is not shown in detail in Figure 1 and Figure 2 , the second vehicle 4 identified is masked so that no light, at least no high beam, shines in its direction. The second vehicle 4 likewise has a vehicle camera 5 which has a field of view 6 and which can correspondingly image the driving environment located in the field of view. Since the second vehicle 4 and in particular the vehicle camera 5 in Figure 1 are located in the darkened area 3, the second vehicle 4 is not dazzled. In order to confirm that there is no dazzle, the second vehicle 4 sends a message that it is not dazzled on the basis of C2C communication when it recognizes the first vehicle 1 by means of its vehicle camera 5.

[0037] A driving situation is shown in Figure 2In the middle, the driving situation changes in that the cut-out area 3 of the light field 2 is not in its intended position and in particular does not shield the second vehicle 4 due to a misalignment of the headlight of the first vehicle 1. Thus, the second vehicle 4 is affected by the light field 2, which in particular refers to glare of the driver of the second vehicle 4. The first vehicle 1 is thus the vehicle causing glare. In this driving situation, the vehicle camera 5 of the second vehicle 4 recognizes the ongoing glare process and the method of the present application for reporting glare by the headlight system of the oncoming vehicle (first vehicle 1) causing glare can be executed in the second vehicle 4.

[0038] In Figure 1 a schematic diagram of the driving situation shown in Figure 2 and Figures 3A to 3C is shown. The light field 2 generated by the first vehicle 1 has here a first section 31 and a second section 32. The cut-out area 3 is located between these two sections, by means of which the second vehicle 4 shall be shielded. The arrow 33 indicates the trajectory of the second vehicle 4. For simplification, a top view of the driving situation shown in Figure 1 and Figure 2 is shown here instead of a perspective view of this driving situation from the perspective of the vehicle camera 5 of the second vehicle 4. In the following, the bright-dark transition of one section of the light field 2 will be observed, but all conclusions can be applied analogously to the dark-bright transition of the same section.

[0039] In Figure 1 a scenario is shown in which the headlight system of the first vehicle 1 is set correctly. The trajectory 33 has a first intersection 34 with a section boundary of the light field, which here is the section boundary of the first section 31 outside the lane. In the case of the thus set headlight of the first vehicle 1, no glare of the second vehicle 4 is caused, so that the position of the first intersection 34 in the image of the vehicle camera of the first vehicle 1 corresponds to the intended intersection.

[0040] In Figure 2 a scenario is shown in which the headlight is misaligned to the right, i.e. is oriented too far to the middle of the lane. As a result, the cut-out area 3 does not sufficiently mask the second vehicle 4, so that the second vehicle is dazzled by the light field 2 of the first vehicle 1. The trajectory 33 reconstructed from the image data of the vehicle camera of the first vehicle 1 has a second intersection 35 with the observed section boundary of the light field 2 (section boundary of the first section 31 outside the lane), which has an offset with respect to the first intersection 34. The first vehicle 1 can derive from this offset the direction as well as the amount of misalignment and use these two results for correcting the projected light field 2, in particular the position of the cut-out area 3, in order to mask the vehicle 4.

[0041] Finally in Figure 3A a scenario is shown in whichFigure 3B The scenario of the coupling shown in Fig. 4, wherein the headlight system is offset to the left, i.e. is oriented too far to the outside of the lane. As a result, the dimmed area 3 does not sufficiently mask the second vehicle 4, so that the second vehicle is dazzled by the light field 2 of the first vehicle 1 (this time by the second segment 32). The trajectory 33 reconstructed from the image data of the vehicle camera of the first vehicle 1 has a third intersection 36 with the observed segment boundary of the light field 2 (the segment boundary of the first segment 31 to the outside of the lane), which has an offset amount with respect to the first intersection 34. Similar to the previous case, the first vehicle 1 can learn from this offset amount the direction as well as the offset amount and use both results for correcting the projected light field 2, in particular the position of the dimmed area 3, in order to mask the vehicle 4.

[0042] In Figure 3C A flow chart is shown in Fig. 5, which shows embodiments of the two methods of the application in a form related to each other. Here, embodiments of the method for reporting a dazzle by a headlight system of an oncoming vehicle that causes a dazzle (hereinafter referred to as the first method) are shown in a first area 41, while embodiments of the method for determining a misalignment of a headlight system of a vehicle that causes a dazzle (hereinafter referred to as the second method) are shown in a second area 42. With reference to the driving situation shown in the previous figures, the method steps from the first area 41 can be implemented in the second vehicle, which can be dazzled, 4. Then, the method steps from the second area 42 can be implemented in the first vehicle, which can cause a dazzle, 1.

[0043] The first method is started in a first step S1. This is followed by a second step S2, in which it is examined on the basis of the image data of the vehicle camera whether an oncoming vehicle is recognized by means of a corresponding image processing algorithm. If this is not the case, the first method proceeds to the first step S1. This cycle can be performed continuously at predetermined time intervals. If an oncoming vehicle is recognized, a unique identity identifier is assigned to the oncoming vehicle in a third step S3. It is then examined in a fourth step S4 whether a dazzle process caused by the oncoming first vehicle 1 can be recognized. If this is not the case, a message of the absence of a dazzle is generated in a fifth step S5. This message additionally includes the position of the second vehicle 4 as well as the identity identifier assigned to the oncoming vehicle 1, wherein the latter specifies the addressee of the message. The message is emitted by means of a radio communication module, whereupon the first method returns to the initial first step S1. In the case of a detection of a dazzle process by means of the vehicle camera 5 of the second vehicle 4, a message of the presence of a dazzle is generated in a sixth step S6. This message likewise additionally includes the position of the second vehicle 4 as well as the identity identifier assigned to the oncoming vehicle 1.

[0044] At this point, the transition from the first method to the second method takes place. By receiving the message generated by the second vehicle 4, the first vehicle 1 performs in a seventh step S7 the determination of the trajectory of the oncoming vehicle, i.e. the second vehicle 4. The acquired trajectory is then forwarded for further processing within the system. In an eighth step S8, it can be checked for safety reasons whether no message of non-glare has been received from the vehicle assumed to be dazzling before. If no such message exists, it is checked in the eighth step S8 that there is glare. Therefore, in the following ninth step S9 the real intersection between the acquired trajectory 33 of the second vehicle 4 being dazzled and the light field 2 is compared with the theoretically expected intersection between the acquired trajectory 33 of the second vehicle 4 being dazzled and the boundary position of the corresponding section of the light field 2 saved in the system of the first vehicle 1. These procedures are basically carried out as described above by means of Figure 3B Figure 4 Figures 3A to 3C In a final step S10, a correction value for the position of the dimming region 3 within the light field 2 is finally calculated from the position comparison of the real intersection and the theoretically expected intersection. This correction value can be applied to the glare protection in order to obtain a correct shielding of the second vehicle.

Claims

1. A method for determining misalignment of a headlight system of a vehicle causing glare, comprising the steps of: receiving, by means of a wireless receiving module of the vehicle causing glare, from an oncoming vehicle, a message that a vehicle being dazzled has detected glare, wherein the message contains information about the position of the vehicle being dazzled at the time of detecting glare; determining, by means of a vehicle camera of the vehicle causing glare, a trajectory of the oncoming vehicle being dazzled; determining a first intersection between the trajectory of the oncoming vehicle being dazzled and a light field generated by the headlight system of the vehicle causing glare; obtaining a second intersection between the trajectory of the oncoming vehicle being dazzled and a model of the light field generated by the headlight system of the vehicle causing glare, the model being stored in a vehicle system; calculating misalignment of the headlight system of the vehicle causing glare by comparing the first intersection with the second intersection, wherein the position of the first intersection has an offset amount with respect to the second intersection, from which the vehicle causing glare learns a direction and an offset amount, and uses both results to correct the light field projected by the headlight system of the vehicle causing glare.

2. The method according to claim 1, wherein the position of the vehicle being dazzled at the time of detecting glare corresponds to a position at which an optical sensor exceeds a bright-dark boundary or a dark-bright boundary generated by the headlight system of the vehicle causing glare.

3. The method according to claim 1 or 2, further comprising the step of: correcting the light field generated by the headlight system based on the calculated misalignment.

4. The method according to one of claims 1 to 2, wherein the message contains information about the time of detecting glare by the vehicle being dazzled.

5. The method according to one of claims 1 to 4, wherein the message contains an identity identifier of the vehicle being dazzled.

6. A glare detection module for a vehicle, the glare detection module being coupled with a wireless transceiver module and a vehicle camera and being adapted to implement a method for reporting glare caused by a headlight system of an oncoming vehicle causing glare and a method for determining misalignment of a headlight system according to any one of claims 1 to 5, the method for reporting glare caused by a headlight system of an oncoming vehicle causing glare comprising the steps of: detecting, by means of an optical sensor in the vehicle being dazzled, glare in the vehicle being dazzled caused by the oncoming vehicle causing glare, wherein glare is detected when the optical sensor exceeds a bright-dark boundary or a dark-bright boundary generated by the headlight system of the vehicle causing glare; generating a message that glare has been detected, wherein the message has information about the position of the vehicle being dazzled at the time of detecting glare; sending, by means of a wireless sending module of the vehicle being dazzled, the message to the vehicle causing glare.

7. The glare detection module according to claim 6, wherein the message contains an identity identifier of the vehicle being dazzled.

8. The glare detection module according to claim 6 or 7, wherein the message contains information about the time of the detected glare.

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