Method for determining the beam range of a headlight

Abstract

A method for determining the range of a vehicle's headlight, wherein, depending on the position of a second vehicle traveling in front of the vehicle in the direction of travel, a range for the vehicle is determined and a relative height position of the vehicle in front is recorded using a camera, wherein it is checked whether the vehicle is braking and this is detected by monitoring the actuation of a brake pedal, wherein, upon detection of braking, the determined range is reduced by a correction value which depends on a dip in the road surface traversed by the vehicle, the vehicle's inclination relative to its normal inclination, the magnitude of the vehicle's negative acceleration during braking, the relative speed of the two vehicles to each other and the direction of travel of the second vehicle.

Description

[0001] The invention relates to a method for determining the luminous range of a headlight according to claim 1 and a computing unit for carrying out the method according to claim 2.

[0002] DE 10 2008 025 948 A1, DE 199 29 906 A1 and DE 10 2012 200 040 A1 (the latter as subsequently published prior art pursuant to Section 3 (2) PatG) each disclose the subject matter of the preamble of claim 1.

[0003] A method for determining the headlight range setting of a vehicle is known from DE 10 2008 031 947 A1. The method comprises determining the vehicle's position relative to its surroundings and determining the headlight range setting using this determined position. Furthermore, the adjustment time required to perform an automatic headlight range adjustment on the vehicle to the determined setting is determined, and any change in the vehicle's position during this adjustment time is predicted. By combining the headlight range setting determined based on the vehicle's position with the predicted change in the vehicle's position during the adjustment time, a corrected headlight range setting is determined.

[0004] The object of the invention is to provide an improved method for determining a beam range that enables good illumination of the road while simultaneously reducing or avoiding glare for other vehicles, even under extreme conditions.

[0005] The problem of the invention is solved by the method according to claim 1 and by the computing unit according to claim 2.

[0006] Further advantageous embodiments of the invention are specified in the dependent claims.

[0007] One advantage of the described method is that the vehicle's headlight range is adjusted by a correction value depending on the braking process. The headlight range is shortened when braking occurs compared to when braking is not taking place. This ensures that, in the event of an abrupt end to braking, when the front of the vehicle and thus the headlights tilt sharply upwards, glare to a second vehicle driving in front is reliably avoided.

[0008] In one embodiment, the correction value depends on another parameter. This allows the correction value to be individually adjusted, thus enabling precise correction.

[0009] In another embodiment, the correction value is determined based on the road surface contour, particularly its vertical contour. This method is especially advantageous when driving through a dip in the road. When driving through a dip, the headlight's range is increased relative to its normal position, particularly to the extent of another vehicle traveling in front of the vehicle in the direction of travel. According to the described method, when braking occurs, the headlight range is reduced again by a defined correction value. This ensures that sufficient overall reaction time is available within the system when the brake is subsequently released, so that the upward tilting of the front of the vehicle after brake release is adequately compensated and the driver of the vehicle ahead is not dazzled.

[0010] The correction value is determined based on the vehicle's inclination relative to a defined normal inclination. The normal inclination is, for example, defined by the vehicle's inclination without braking. This allows the upward tilting of the front end caused by releasing the brakes to be estimated and taken into account when determining the correction value.

[0011] In another embodiment, the correction is only carried out when the vehicle is driving through a dip in the road. In the area of ​​the dip, the driver hardly perceives a reduction in the headlight range as bothersome, since a relatively large range is established due to the dip itself.

[0012] In any case, the correction value for the headlight range is determined depending on the speed, the braking deceleration, and whether the vehicle ahead is traveling in the same or opposite direction. This ensures optimal headlight range correction without dazzling the driver of the vehicle ahead, especially during braking.

[0013] The system uses a camera to detect the position of the vehicle ahead and adjusts the headlight range based on the camera data. Using a camera ensures safe and reliable detection of the vehicle's position. The vehicle ahead can be traveling in the same direction or approaching from the opposite direction. This information can also be factored into the headlight range correction.

[0014] According to the invention, the occurrence of a braking process is detected by monitoring the actuation of a brake pedal. This enables fast and reliable detection of a braking process.

[0015] The invention will be explained in more detail below with reference to the figures.

[0016] They show Fig. 1 a schematic representation of two vehicles on a road, Fig. 2 a schematic representation of a vehicle, and Fig. 3 a schematic representation of the procedure for controlling the headlight range.

[0017] Fig. Figure 1 shows a schematic representation of a driving situation in which a vehicle 1 is traveling on a road 3 in one direction, turning right. Another vehicle 2 is approaching vehicle 1 on the same road 3. Vehicle 1 uses a camera to detect the height of the other vehicle 2 relative to vehicle 1. The camera can also detect whether the other vehicle 2 is traveling in the same or opposite direction to vehicle 1. The camera transmits this information to a processing unit, which, based on the position of the other vehicle relative to vehicle 1 and preferably on the direction of travel of the other vehicle 2, determines a beam range for vehicle 1 that preferably extends to the other vehicle 2 without dazzling the driver of the other vehicle 2.When the relative height position and / or the distance of the other vehicle 2 to the other vehicle 1 changes, the headlight range of vehicle 1 to the other vehicle 2 is also adjusted, i.e. a sliding headlight range adjustment is carried out.

[0018] Specific driving situations, such as braking, cause the headlight range to decrease due to the lowering of the front of the vehicle. The control unit would detect and compensate for this lowering by maintaining the headlight range, i.e., by tilting the headlight upwards. Contrary to this approach, it is now proposed that when a braking maneuver is detected, the headlight range control should not compensate for the lowering of the front of the vehicle, or at least not completely. This situation is schematically illustrated in Fig. 1 is shown in such a way that, according to the sliding headlight range control, when the vehicle 1 brakes, the headlight range is adjusted upwards up to an upper edge 4, so that the illuminated area extends to the next vehicle 2.

[0019] According to the new procedure, when a braking maneuver is detected, the sliding headlight range control is adjusted with a correction value, and a lower second height 5 is set for illumination. This means that the entire available area up to the next vehicle 2 is not illuminated. However, this prevents the driver of the next vehicle 2 from being dazzled when the brake is released and the front of vehicle 1 tilts abruptly upwards. This is because the headlights of vehicle 1 also tilt upwards, and the headlight range control, due to its delayed reaction, is unable to compensate for this upward tilt. By reducing the beam range when the brake of vehicle 1 is released, the driver of the next vehicle 2 is not dazzled by the abrupt upward tilt of the front of vehicle 1.Due to the inherent dead times caused by signal measurement, transmission, processing, and the corresponding control and adjustment of the headlight drive, the processing unit cannot compensate for the vehicle's abrupt upward tilting after the brake is released using the sliding headlight range control. Therefore, to prevent mis-illumination and glare for other vehicles, the headlight range is reduced by a configurable correction value. This procedure can be particularly useful when driving through a dip, i.e., a road surface with a concave contour. For example, if a tilt sensor or prior information such as map data detects that vehicle 1 is driving through a dip, the processing unit can activate this new procedure.If the control unit detects that braking is occurring, for example by monitoring the brake pedal or an acceleration sensor, it executes the described procedure and corrects the headlight setting determined by the variable-width modulation system. The correction value depends on other parameters. For example, one parameter could be the distance between the two vehicles 1 and 2. The correction value depends on the speed of vehicle 1 relative to the speed of vehicle 2 and the direction of travel of vehicle 2. Tables, characteristic curves, and / or calculation methods are stored to account for these parameters.

[0020] The described procedure can also be applied on a straight stretch of road or when driving over a crest. A dip in the road offers a geometric advantage, meaning that a slightly reduced illumination in the dip hardly impairs the driver's visibility, since the illumination is already good in the dip, especially as the beam reaches over the lowest point of the dip. Even after adjusting the beam range, better illumination is achieved than with the normal range of the low beam.

[0021] Fig. Figure 2 shows a schematic representation of the components of vehicle 1. Vehicle 1 has a processing unit 6, which is connected to a camera 7. The processing unit 6 can adjust the direction of the headlights 10 and thus the beam range by controlling the drive 8. The processing unit 6 is also connected to a drive 8 of a headlight 10. Furthermore, the processing unit 6 is connected to a sensor 9, which detects, for example, the actuation of a brake pedal. The processing unit 6 is also connected to other sensors 11, which are configured, for example, as acceleration sensors and / or tilt sensors. Using sensor 9, the processing unit can detect a braking process. Additionally, the processing unit 6 can use the other sensors 11 to detect whether the vehicle is traveling through a dip in the road.For example, a dip in the road can be detected if the vehicle has lowered its front end by five degrees relative to a horizontal position, without any deceleration, i.e., without any braking.

[0022] Furthermore, the processing unit 6, with the help of the additional sensors 11, can also detect a braking process based on negative acceleration. Additionally, the processing unit 6, with the help of the tilt sensors, can detect a downward tilt of the front of the vehicle caused by braking. Thus, the processing unit 6 can, for example, take the magnitude of the angle of tilt caused by braking into account when determining the correction value.

[0023] Furthermore, the processing unit 6 is connected to a navigation device 12, which contains map information. This allows the processing unit 6 to recognize, based on the vehicle's position (determined, for example, using a GPS system) and the map information, whether the vehicle 1 is passing through a dip in the road. The additional sensors 11 can also detect the vehicle 1's speed. Thus, the processing unit can also take the vehicle 1's speed into account when determining and / or adjusting the correction value.

[0024] Fig.Figure 3 shows a schematic representation of the described procedure. At program point 20, the processing unit 6, located in vehicle 1, performs headlight range control for the vehicle's headlights. The processing unit 6 takes into account, for example, information from camera 7 about the position of another vehicle 2 driving in front of vehicle 1. Furthermore, the processing unit 6 considers the inclination of vehicle 1, which is determined, for example, by the additional sensors 11, when calculating the headlight range. The processing unit 6 can also consider information about the surroundings, in particular the road's contour, which is provided, for example, by map data from the navigation device. Depending on at least one of the described parameters, the processing unit 6 determines a headlight range for vehicle 1.The beam range is usually determined as close as possible to the next vehicle 2 driving ahead, so that the driver of the vehicle has the best possible illumination of the road and the driver of the next vehicle is not dazzled.

[0025] In a subsequent program step 21, which is only executed optionally, the processing unit can check whether the vehicle is passing through a dip in the road. This can be determined, for example, using a tilt sensor or by using the vehicle's position and map information. If the check at program step 21 shows that no dip is being traversed, the program branches back to program step 20. If the check at program step 21 shows that the vehicle is passing through a dip, the program then branches to program step 22. As already described, the new method is particularly suitable for passing through a dip in the road, but can also be applied to other road contours. Thus, the check at program step 21 is only optional. In the embodiment where program step 21 is not included, the program branches directly from program step 20 to program step 22.

[0026] At program point 22, the processing unit 6 checks whether a braking process is taking place. If no braking process is taking place, the system branches back to program point 20. However, if the processing unit 6 detects that a braking process is taking place, for example, by querying a sensor that detects brake pedal actuation or by querying an acceleration sensor, then at the following program point 23, the processing unit 6 specifies a correction value by which the headlight range determined by the variable headlight range control is reduced. Depending on the selected configuration, the correction value has a fixed value. In addition, the correction value can also depend on other parameters, such as the distance between the two vehicles.In any case, it depends on the direction of travel of the other vehicle, the relative speed of the two vehicles to each other, the magnitude of the negative acceleration of the braking process, and an inclination, i.e., tilting of the front vehicle, caused by the braking process.

[0027] The processing unit subtracts the correction value from the headlight range control value and sends the corrected headlight range value to the headlight drive of vehicle 1. Thus, the headlight range is reduced by the correction value when braking occurs. The program then returns to step 20.

[0028] Depending on the selected configuration, the headlight range adjustment is performed by a program in processing unit 6. The correction value is determined by a second program through a simple query to determine whether braking is occurring. The correction value can thus be calculated and applied quickly and easily.

Claims

[1] Method for determining the range of a vehicle's headlight, wherein, depending on the position of a second vehicle traveling in front of the vehicle in the direction of travel, a range for the vehicle is determined and a relative height position of the vehicle in front is recorded using a camera, wherein it is checked whether the vehicle is braking and this is detected by monitoring the actuation of a brake pedal, wherein, when a braking process is detected, the determined range is reduced by a correction value which depends on a dip in the road surface traversed by the vehicle, an inclination of the vehicle relative to a normal inclination of the vehicle, a magnitude of the negative acceleration of the vehicle during the braking process, a relative speed of the two vehicles to each other and a direction of travel of the second vehicle. [2] Computing unit (6) configured to perform a method according to claim 1.

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