Lighting system for a motor vehicle and method for adjusting a lighting unit of such a lighting system

Abstract

Lighting system for a motor vehicle, comprising a control unit (26), at least one image acquisition unit (10), and at least one light unit (12) comprising at least one light source (14), wherein the light unit (12) is adjustable by means of at least one actuator (28), and wherein the light unit (12), in its activated state, generates a light distribution with light-dark boundaries (16), abbreviated as HDGs, and projects it onto a projection surface (4) located in the traffic space (19), such that adjustment of the light unit (12) is possible by means of the control unit (26), wherein at least two points P1, P2 of an HDG (16) can be determined by means of the image acquisition unit (10), wherein the control unit (26) is connected to the actuator (28) in such a way that a superposition of the two points P1, P2 is possible and can be evaluated in the control unit (26), characterized in thatthat in the control unit (26) points P1Soll and P2Soll are stored by means of direction vectors rasoll and resolt, wherein a rotation matrix multiplication ra¯=(Dφ×Dψ×re¯) is stored as the arithmetic operation in the control unit.

Description

The invention relates to a lighting system for a motor vehicle, comprising a control unit, at least one image acquisition unit, and at least one light unit comprising at least one light source, wherein the light unit is adjustable by means of at least one actuator and wherein the light unit, in the activated state, generates a light distribution with light-dark boundaries, abbreviated HDGs, such that adjustment of the light unit by means of the control unit is possible. Such a lighting system, or a method for adjusting a lighting unit of such a lighting system, is known, for example, from DE 10 2010 046 517 A1. The known method involves calibrating or adjusting the lighting unit with respect to light boundaries (HDGs) when the vehicle is inactive. For this purpose, the vehicle is positioned at a defined distance in front of a surface such that the lighting unit can project an image onto the surface and the image capture unit can detect and evaluate light-dark boundaries. This is intended to ensure optimal illumination of the area in front of and to the sides of the vehicle while it is in motion. Furthermore, fine adjustments to the light distribution within the HDGs can be made while the vehicle is in motion.For the initial adjustment, the vehicle must be stationary and a defined surface must be provided on which the light-dark boundaries can be projected. A complex calibration / adjustment procedure is then carried out. Quick adjustments, for example to a specific loading situation, are not possible with this method. Document DE 10 2010 006 190 A1 discloses a method for adjusting a vehicle's lighting unit. In this method, at least one image of the light distribution is captured by means of at least one image acquisition unit of the vehicle, and by evaluating the at least one captured image in an image evaluation unit, a horizontal and / or vertical position of at least a predefined part of the light distribution is determined and compared with a corresponding target position. In case of a deviation, a warning message is generated for the driver, or appropriate adjustment means are activated for correction. Document DE 10 2008 025 458 A1 discloses a method and a device for calibrating at least one horizontal light-dark boundary generated by at least one headlight of a vehicle. In this process, at least one image depicting an area in front of the vehicle is captured, and the actual position of the light-dark boundary is determined. A correction value is then calculated if there is a deviation from a target position. Therefore, the task is to provide a lighting system or a method for adjusting a light unit of such a lighting system, thereby avoiding the aforementioned disadvantage. This task is accomplished by a lighting system for a motor vehicle by using an image acquisition unit to determine at least two points P1 and P2 of a high-definition field (HDG). The control unit is connected to the actuator in such a way that the two points P1 and P2 can be superimposed and evaluated within the control unit. This allows the lighting unit to be adjusted automatically or manually while the vehicle is stationary, for example, at a traffic light or in a traffic jam. The lighting system can thus be individually adapted to the specific conditions of each operating situation. This individual adaptation is achieved solely through the acquisition of at least two points (HDG) and the special design of the control unit, eliminating the need for complex environmental sensors. Advantageously, a camera can be used as the image acquisition unit, whereby both a mono camera and a stereo camera, a 2D-3D-PMD camera can be used. According to the invention, points P1Set and P2Set are defined in the control unit by means of direction vectors rasSet and reSet. Furthermore, a rotation matrix multiplication is defined as a computational operation in the control unit. Furthermore, the problem is solved by a method for adjusting a light unit of a lighting system according to one of the preceding claims, characterized in that in a first step the HDGs are imaged onto a surface, that in a second step at least one first point P1 and at least one second point P2 of the HDG are determined, that in a third step these image data of P1 and P2 are transmitted to the control unit, that in a fourth step the actuator brings point P1 into superposition with point P2 by means of a reference run, that in a fifth step the reference run data are transmitted to the control unit, that in a sixth step the reference run data are compared with the stored target run data in the control unit, and that in case of deviation in a seventh step the light unit is adjusted by means of the actuator.According to the invention, in the sixth step, the comparison of the reference running data with the stored target running data is carried out by means of a rotary matrix multiplication. In principle, it should be noted that several values ​​can be determined for readjustment, from which an average value is then calculated. Individual, significantly deviating measured values ​​can thus be compensated for. The comparison itself is essentially a recording of the deviation values, whereby the minimum values ​​are essential for the tracking. The invention is explained in more detail below with reference to a drawing, in which: Fig. 1 shows a schematic view of a vehicle in operation, in which an adjustment of a light unit of a lighting system is carried out, Fig. 2a, Fig. 2b a schematic representation of the operation of the rotary matrix multiplication, and Fig. 3 a block diagram for adjusting a light unit of the lighting system. Fig. 1 shows a vehicle 2 in operation, but stationary, for example at a traffic light or in a traffic jam, or parked against a garage front 4. The vehicle 2 has a lighting system 6, which in the present embodiment comprises a control unit 26 (schematically shown in Fig. 3), an image acquisition unit 10 arranged in the front area, and two light units 12, each with a headlight 14 as its light source. In this embodiment, the image acquisition unit 10 is located in the front of the vehicle 8. An arrangement in the area of ​​the interior rearview mirror, for example in the mirror base, is also possible. It should be clear that, for the sake of simplicity, this embodiment assumes only one light source with one headlight. Furthermore, the following description relates only to the adjustment of one light unit 12. Due to a heavy load on the vehicle 2, the light-dark boundary 16, shown in solid lines, appears on the projection surface 4 when the headlights 14 are switched on. This light-dark boundary is defined in particular by points P1 and P2. A further light-dark boundary 18 is shown in dashed lines, which describes the target light-dark boundary stored in the control unit 26 with points P1Target and P2Target. Corresponding direction vectors rasoll and resoll are stored in the control unit 26 for points P1Target and P2Target of the target light-dark boundary. The image acquisition unit 10 captured points P1 and P2, and this image data acquisition is sufficient to carry out the procedure for adjusting the light unit 12 described below. First, however, the calculation operation (rotation matrix multiplication) will be illustrated below using Figures 2a and 2b. A reference run will be shown using the example of moving from point a to point e. First, a rotation by the angle φ1 to point b and a rotation by the angle ψ1 to point c is performed. Then, a rotation by the angle ψ2 to point d is performed, and finally, a rotation φ2 to point e. The starting vector to point a is denoted by and the target vector to point e by . The target vector is thus . Using rotation matrix multiplication, a change in the position of the light unit can be detected in a particularly simple way and compensated for or adjusted by means of an actuator (not shown). The procedure for adjusting the lighting unit 12 will now be explained in more detail using the block diagram shown in Fig. 3 and with the aid of Fig. 1. In a first step, the HDGs 16 are projected onto a projection surface 4 located in the traffic area 19. This is done by activating the headlights 14, indicated by arrow 20. In a second step, a first point P1 and a second point P2 of the HDG 16 are determined by the image acquisition unit 10, indicated by arrow 22. Arrow 24 shows the transmission of this image data from P1 and P2 to the control unit 26 in a third step. The control unit 26 is also connected to the actuator 28, which, in a fourth step, uses a reference run to superimpose the determined point P1 with point P2 (arrow 29).In a fifth step, these reference running data are transmitted to the control unit 26, using vector form for representation. In a sixth step, the control unit 26 then performs a comparison of the reference running data (minimum value analysis based on the vector equations) with the stored target running data by means of a rotary matrix multiplication. This reveals the misalignment of the headlights 14, which can be readjusted by the actuator 28, as shown by arrow 30. Optimal light distribution is now ensured, either by using the low beam of the headlights 14 or by special functions such as tracking, dimming, or marking, as shown by block 32 and arrow 34. It should be clear that the headlight adjustment does not need to be permanent.Incorrect settings for a specific adjustment can be saved and integrated into the adjustment process for future settings. Furthermore, it should be clear that the rotation matrix multiplication is defined with respect to the headlight center point. If, as is usually the case, the image acquisition unit deviates from the headlight center point, the captured image data must be scaled to the headlight center point to be set using appropriate calculations.

Claims

Lighting system for a motor vehicle, comprising a control unit (26), at least one image acquisition unit (10), and at least one light unit (12) comprising at least one light source (14), wherein the light unit (12) is adjustable by means of at least one actuator (28), and wherein the light unit (12), in its activated state, generates a light distribution with light-dark boundaries (16), abbreviated HDGs, and projects it onto a projection surface (4) located in the traffic space (19), such that adjustment of the light unit (12) is possible by means of the control unit (26), wherein at least two points P1, P2 of an HDG (16) can be determined by means of the image acquisition unit (10), wherein the control unit (26) is connected to the actuator (28) in such a way that a superposition of the two points P1, P2 is possible and can be evaluated in the control unit (26), characterized in thatthat in the control unit (26) points P1Soll and P2Soll are stored by means of direction vectors rasoll and resolt, wherein in the control unit a rotation matrix multiplication ra ¯ = ( D φ × D ψ × re ¯ ) is used as a computational operation. is stored. Lighting system according to claim 1, characterized in that a stereo camera, a 2D-3D PMD camera or a mono camera can be used as the image acquisition unit (10). A method for adjusting a light unit (14) of a lighting system (12) according to claim 1 or 2, characterized in that in a first step the HDGs (16) are imaged onto a surface (4), that in a second step at least one first point P1 and at least one second point P2 of the HDG (16) are determined, that in a third step these image data of P1 and P2 are transmitted to the control unit (26), that in a fourth step the actuator (28) brings point P1 into superposition with point P2 by means of a reference run, that in a fifth step the reference run data are transmitted to the control unit (26), that in a sixth step in the control unit (26) the reference run data are compared with stored target run data on the basis of a minimum value analysis, and that in case of deviation in a seventh step the light unit (14) is adjusted by means of the actuator,where the comparison of the reference run data with the stored target run data is carried out by a rotary matrix multiplication.

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