Motor vehicle and method for operating a motor vehicle

Abstract

The invention relates to a motor vehicle (1) having a plurality of externally directed light-emitting devices (5), comprising at least one measuring light-emitting device (5) having at least one light source, the light source of which can be used to emit light and to measure incident light, and having a control device (10), which is designed to control the light source of the measuring light-emitting device (5). The invention relates to a control device (10) for evaluating measurement data of a light source determined in a measurement mode, the control device (10) being designed to determine ambient brightness information describing an ambient brightness of the surroundings of the motor vehicle (1) from the measurement data and to actuate at least one vehicle system (20) using the ambient brightness information, the motor vehicle (1) has at least two measuring lighting devices (5) which are arranged at different positions on the motor vehicle (1) and / or which point in different directions, and the control device (10) is designed to analyze the measurement data of the respective measuring lighting devices (5) in combination when determining the ambient brightness information.

Description

TECHNICAL FIELD

[0001] The invention relates to a motor vehicle having a plurality of light emitting devices directed to the outside, the light emitting devices comprising at least one measuring light emitting device, the measuring light emitting device having at least one light source, wherein the light source of the measuring light emitting device is usable for emitting light and for measuring incident light, and the motor vehicle further having a control device designed to evaluate measurement data determined by the light source in a measurement mode. Furthermore, the invention also relates to a method for operating such a motor vehicle. BACKGROUND

[0002] Motor vehicles usually have a plurality of light emitting devices acting to the outside, thus directed to the outside, which on the one hand can be used for illuminating the surrounding environment and which on the other hand additionally or alternatively contribute to improving the recognizability of the motor vehicle. For example, motor vehicles usually comprise headlamps / front lamps for illuminating the area in front of the motor vehicle and tail lamps which at least provide the function of a rear light (as a side marker light). In this type of tail lamp, a brake light can also be integrated. Furthermore, motor vehicles can comprise, as light emitting devices, direction indicator lights, license plate lights and side marker lights (side lights), for example. A plurality of other functional light emitting devices are also conceivable, for example light emitting devices for illuminating the boarding area and the disembarking area.

[0003] At least with regard to light emitting devices for improving the recognizability of the motor vehicle and for illuminating the surrounding environment of the motor vehicle for the driver, it is known to employ different operating modes, for example "daytime running light", "low beam", "high beam" and the like. In many motor vehicles, these operating modes can also be switched automatically, for example depending on information about the overall ambient brightness in the surroundings of the motor vehicle. Such ambient brightness information can be provided, for example, by means of a light sensor, for example a so-called rain light sensor.

[0004] The light emitting devices of modern motor vehicles are usually segmented, that is to say, they have independently controllable light sources and / or independently illuminable segments in their illumination area. For example, for headlamps, so-called digital matrix lamps have been proposed, which can be implemented by means of an array of light emitting diodes and / or a micromirror device. For tail lamps and other light emitting devices, light emitting diodes can likewise be provided as light sources, for example also organic light emitting diodes (OLEDs).

[0005] For light emitting diodes as light sources, it has also been proposed to employ, in addition to an illumination mode in which the respective light emitting diode emits light, also a measurement mode in which the light emitting diode measures incident light in the manner of a photodiode, for example for detecting an oncoming road user by means of the headlamps of the motor vehicle.

[0006] That is, for example, DE 10 2008 032 345 A1 discloses a headlight for a motor vehicle, which has a light source device for generating a preset light distribution and a light sensor device for detecting the brightness in the area in front of the motor vehicle. In the case where the light-emitting diodes are in the dark state, incident light rays of a traffic object can be recognized and the high beam is controlled to mask the traffic object.

[0007] DE 10 2019 128 401 A1 relates to a method and a control unit for operating a lighting unit as a light sensor. It is proposed here that the light-emitting diodes are operated as light sources in a first time period and, in a second time period, the light-emitting diodes are operated as a light sensor to acquire measurement data relating to the lighting conditions in the surroundings of the lighting unit. From the measurement data, it is determined whether an object is present in the surroundings of the lighting unit. In particular, the lighting unit is assigned to a video camera and illuminates the detection area of the video camera.

[0008] DE 101 03 702 A1 relates to an electronic device for the dual control and evaluation of light sources, preferably light-emitting diodes. Here, in one and the same lighting device, light rays should be generated on the same signal path and the brightness should be measured on the opposite signal path. For example, in the case of a brake light, the ambient brightness in the same direction can be precisely measured in the same direction as the light rays emitted by the vehicle signal light in order to adapt the brightness.

[0009] DE 10 2005 042 082 A1 relates to a circuit arrangement with light-emitting diodes and a method for controlling light-emitting diodes, in which the ambient brightness is measured by the light-emitting diodes working as detectors. The physical effect utilized here is that each light-emitting diode works as a photodiode (respectively as a light-sensitive element) in the case where it is not actively controlled. Thus, a measure of the ambient brightness can be obtained to control the brightness of the light-emitting diodes.

[0010] DE 10 2005 018 175 A1 relates to an LED module and an LED lighting device with a plurality of LED modules, in which the operating current is adjusted in accordance with stored operating data in order to achieve a high degree of long-term stability of the emitted light intensity and to prepare for replacement. An additional light detector (for example a photodiode) can also be provided for measuring the ambient brightness and the operating current of the LED chips is adapted to the ambient lighting conditions. An automatic switching-on or switching-off process is also mentioned. SUMMARY

[0011] It is therefore an object of the present application to give a motor vehicle which is improved in the recognition of the global lighting conditions of the surroundings of the motor vehicle and changes thereof.

[0012] According to the application, this object is achieved by a motor vehicle having the features of claim 1 and by a method having the features of claim 9.

[0013] In a motor vehicle of the type mentioned at the outset, according to the application it is provided that the control device is designed to determine, from the measurement data, ambient brightness information describing the ambient brightness of the environment of the motor vehicle, and to control at least one vehicle system using the ambient brightness information, wherein the motor vehicle has at least two measurement light devices arranged at different locations on the motor vehicle and / or pointing in different directions, wherein the control device is designed to combine the measurement data of the individual measurement light devices in determining the ambient brightness information.

[0014] The ambient brightness information relates to the global lighting conditions, i.e. the overall lighting conditions, in the environment in which the motor vehicle is located, in particular is running or driving. In other words, the ambient brightness information does not describe the lighting variations or light effects of individual lighting elements, for example, but rather describes the diffuse lighting situation outside the motor vehicle, for example, which is formed as a result of the sun's position and cloud cover conditions, possibly also as a result of extensive switching off, or rather as a result of distributed lighting means for providing overall lighting in enclosed spaces, for example, parking lots or tunnels. In other words, the ambient brightness information relates to the information on the overall ambient brightness which has hitherto been provided by light sensors. By using the light devices of the motor vehicle for measuring the overall ambient brightness, it is possible to dispense with dedicated light sensors. The corresponding costs and the corresponding effort can be saved.

[0015] The at least one light source of the measurement light device can in particular be a light-emitting diode. The application thus makes use of the fact that light-emitting diodes (LEDs) can also be used "in reverse", i.e. in the form of photodiodes, and thus for measuring brightness. Suitably, the measurement light device at this point comprises a plurality of light sources, in particular light-emitting diodes, the measurement data of which can be processed in a statistical manner for improving the measurement accuracy. For example, the measurement light device can comprise a light-emitting diode device, in particular a light-emitting diode matrix or a light-emitting diode array. The control device can be designed to detect local effects, for example local illumination or local switching off as a result of lighting elements outside the motor vehicle, and to exclude the affected data from the evaluation when evaluating the measurement data of the plurality of light sources of the measurement light device in a statistical manner. In particular in the case of the use of a plurality of light sources, in this way it is already possible to determine reliable ambient brightness information values even with the aid of only one measurement light device.

[0016] In this regard, it is also advantageous if the control device is designed to take into account, when determining the ambient brightness information, the orientation of the light source of the measuring light device and / or the time course of the measurement data of the light source of the measuring light device and / or the light rays emitted by the light source or a further light source of the measuring light device. Thus, for the measuring light device, the accompanying circumstances of the measurement can be taken into account as widely as possible in order to improve the quality of the ambient brightness information. For example, from the orientation of the light source, it can be inferred whether the light source is affected by local incident light rays, for example by the illumination of a headlight of another road user. In this regard, it is also extremely advantageous to take into account the time course of the measurement data, since short-term local light effects, such as the illumination of a headlight of another road user, can be identified and taken into account, for example by excluding them when determining the overall ambient brightness, which generally changes only slowly over time. In general, it can be provided that the control device is designed to statistically evaluate the measurement data within a time window comprising a plurality of measurement instants. In this way, it is possible to achieve a further improvement in the quality of the ambient brightness information and to achieve the reliability of the ambient brightness information, especially in the case of a measuring light device having a plurality of light sources, in combination with a statistical combination analysis in space.

[0017] On the other hand, however, the observation of the time course can also provide an indication of events that occur in connection with a relatively rapid change in the overall ambient brightness. For example, the control device can be designed to evaluate the time course of the measurement data in order to detect a tunnel entrance and / or a tunnel exit. For example, if the measured brightness changes from an overall "consistently bright" to an overall "consistently dark", it means that a tunnel entrance or another building is driven into. Corresponding evaluation criteria can thus be formulated. In the case of a measuring light device arranged at intervals along the longitudinal axis of the motor vehicle and when evaluating the corresponding time course, it is possible to detect a tunnel entrance and a tunnel exit particularly quickly and reliably, as will be explained in more detail below

[0018] In addition, the control device can also take into account the own stray light generated by the measuring light device or by adjacent light devices, i.e. the light rays emitted by the light source or a further light source of the measuring light device. It is also conceivable, however, to use an overall pulsed operating mode of the light source of the measuring light device, which has already been proposed in the prior art. In this case, in the ideal case, the measurement can be carried out at instants at which the measuring device itself does not emit any light rays.

[0019] The application provides that the motor vehicle has at least two measuring light devices which are arranged at different locations on the motor vehicle and / or are oriented in different directions, wherein the control device is designed to combine the analysis of the measurement data of the individual measuring light devices when determining the ambient brightness information. It has been recognized that in principle every light emitting diode in the motor vehicle can also be used for measurement, so that the light sources of different locations and / or different orientations can be selected by a clever distribution in order to be able to determine the ambient brightness information in a more robust manner, for example by a plausibility check among one another. In particular, it can be provided here that the plurality of measuring light devices has at least two of the following orientations:

[0020] - pointing towards the front region of the motor vehicle,

[0021] - pointing towards the rear space of the motor vehicle, and

[0022] - pointing towards the side.

[0023] In particular, all four conceivable orientations can also be provided. For example, the measuring light devices can comprise at least one headlight, at least one tail light and at least two opposing side lights. Additionally or alternatively, it can also be provided that the positions of at least two of the plurality of measuring light devices are spaced apart from one another in the longitudinal direction of the motor vehicle. As will also be explained in more detail, it is particularly advantageous if, during the forward movement of the motor vehicle, brightness changes occurring in the longitudinal direction of the motor vehicle should be detected as part of the ambient brightness information, in particular tunnel entries and tunnel exits.

[0024] As mentioned above, the control device can be designed to carry out a plausibility check among one another of the measurement data related to the ambient brightness in the combined analysis. For example, if the light of another road user hits the front or rear measuring light device, it is less likely that the other measuring light device is affected, so that a plausibility check is feasible and reasonable. For example, if a front and a rear measuring light device are used and at least one light source of the front measuring light device measures a high ambient brightness, this false measurement can be identified by an additional measurement at the rear and tested for plausibility.

[0025] It is particularly advantageous if the control device is designed to perform a correlation analysis of the time courses of the different measuring light devices upon detection of a tunnel entrance and a tunnel exit. For example, if a change from light to dark occurs in succession in the front and in the rear of the vehicle, or in other measuring light devices arranged at intervals in the longitudinal direction of the motor vehicle, it can be assumed that a tunnel entrance is being passed. In the evaluation of the correlation, the current speed of the motor vehicle provided to the control device can also be taken into account at this point. In this way, the time intervals of the brightness changes in the time courses are identified, so that the cause of the brightness changes, i.e. the passage of a tunnel entrance or a tunnel exit, can be traced back. In this way, the tunnel entrance and the tunnel exit can be identified significantly more quickly, robustly and reliably. Time delays that often occur in conventional light sensors can be avoided or at least reduced. In this regard, the control device can also be designed to take into account the position and / or the orientation of the measuring light devices. This is also reasonable for a correlation analysis at the same position in the longitudinal direction of the motor vehicle, but with different orientations, since if two measuring light devices of different orientations recognize a brightness change at essentially the same time, this can also be used as a basis for deciding on a tunnel entrance or a tunnel exit.

[0026] In a particularly preferred design, the vehicle system to be controlled in accordance with the ambient brightness information can be a lighting system comprising at least a part of the motor vehicle's light devices, which lighting system comprises the motor vehicle's headlamps, for which the control device implements a passing light switch using the ambient brightness information. Here, the passing light switch refers to a switch between different operating modes depending on the overall ambient lighting conditions. For example, if a nightfall is recognized from the ambient brightness information, the low beam can be activated instead of the daytime running light, or the headlamps can be switched off. The same applies if a tunnel entrance is recognized from the ambient brightness information. At the tunnel exit, or when the daylight reappears, the switch from the current operating mode for dark environments to the daytime running light, or indeed the switching off of the vehicle lights, can be reversed again. In other words, the present application allows a passing light switch between different operating modes of a lighting system depending on the ambient brightness information, which is now also based on the measurement data of the measuring light devices, but which has so far been achieved by means of a dedicated light sensor.

[0027] Other vehicle systems can also be controlled in accordance with the ambient brightness information. For example, if the information indicates that the driver does not want to use the automatic driving function in the tunnel and / or under certain lighting conditions in the case of at least partial automatic driving of the motor vehicle, a corresponding deactivation can be triggered (after the driver has requested to take over or the driver has provided other information), etc.

[0028] Since headlamps and / or tail lamps in motor vehicles are increasingly frequently using light-emitting diodes as light sources, which can also be used in the form of photodiodes, it is particularly recommended that the at least one measuring light device comprises the headlamps and / or tail lamps of the motor vehicle.

[0029] In addition to the motor vehicle, the present application also relates to a method for operating a motor vehicle according to the present application, wherein the measuring data describing the incident light rays are detected by the light sources of the measuring light devices in the measuring mode, and the control device determines the ambient brightness information describing the ambient brightness of the surroundings of the motor vehicle from the measuring data, and actuates at least one vehicle system using the ambient brightness information, wherein in determining the ambient brightness information, the control device combines the analysis of the measuring data of the individual measuring light devices. All embodiments relating to the motor vehicle according to the present application can be similarly transferred to the method according to the present application, so that the advantages already explained can also be achieved by the method. BRIEF DESCRIPTION OF DRAWINGS

[0030] Further advantages and details of the present application result from the following described embodiments and from the attached drawings. Therein:

[0031] Figure 1 A schematic diagram of a motor vehicle according to the present application is shown,

[0032] Figure 2 A schematic diagram of a measuring light device is shown,

[0033] Figure 3 A first example of the time course of the brightness measured by different measuring light devices is shown,

[0034] Figure 4 A second example of the time course of the brightness measured by different measuring light devices is shown, and

[0035] Figure 5 A flow chart of one embodiment of the method according to the present application is shown. DETAILED DESCRIPTION

[0036] Figure 1 A schematic diagram of a motor vehicle 1 according to the present application is shown. The motor vehicle 1 comprises a plurality of light devices, mainly comprising headlamps 2, tail lamps 3 and side lamps 4. The light devices shown here are all measuring light devices 5, which have a plurality of light-emitting diodes as light sources.

[0037] Figure 2An exemplary schematic of such a measuring light device 5 is shown, which has in a housing 6 a light emitting diode device 8 carried by a circuit board 7, which is designed as a light emitting diode matrix or light emitting diode array, with a plurality of light emitting diodes 9. Each light emitting diode 9 can be operated in an illumination mode, in which the light emitting diode emits light, and in a measurement mode, in which the light emitting diode measures incident light as luminance. For example, the light emitting diodes 9 can be operated in a pulsed manner, wherein the illumination mode and the measurement mode can be performed, for example, alternately. If the measuring light device 5 itself emits no stray light at all, the measurement data describing the luminance of the incident light are recorded. But it is alternatively also conceivable to take into account the light emitted by the measuring light device itself, in particular in a correction process.

[0038] Returning to Figure 1 , the motor vehicle 1 has a control device 10, for example a controller, in which the measurement data of the measuring light devices 5 can be evaluated. In particular, the control device 10 determines, without taking into account local or short-time light effects, ambient brightness information describing the overall ambient brightness in the motor vehicle's surroundings, i.e. the global ambient lighting conditions. To achieve this, in particular to exclude local and / or short-time light effects, on the one hand, the control device 10 makes use of the fact that each measuring light device 5 has a plurality of light emitting diodes 9, the measurement data of which can be evaluated in a statistical manner in order to improve the quality of the measurement results and to increase the reliability of the measurement results. A further improvement can be achieved by a temporal statistical evaluation over a time window.

[0039] But the fact that is used in particular to full advantage is that a plurality of measuring light devices 5 distributed over the motor vehicle 1, i.e. measuring light devices arranged at different locations and / or having different orientations, are used, which allows a plausibility check in the control device 10, in particular for excluding short-time and / or local light effects from the analysis performed. For example, Figure 3 A first example of time courses 11, 12 of the measurement data of different measuring light devices 5 is shown. For example, the time course 11 can be measured by one of the headlamps 2 pointing forwards, and the time course 12 can be measured by one of the tail lamps 3 pointing rearwards. Now, the light cone of an oncoming road user now sweeps over the headlamps 2, which is indicated by a peak 14, but this peak is determined only for one or more headlamps 2. Therefore, by means of the further time course 12 it can be determined that the peak 14 is a short-time local light effect which should not be taken into account.

[0040] The ambient brightness information can also describe: driving into a tunnel (or other enclosed building) or driving out of the tunnel again. At this point, it is possible to determine the tunnel entrance and the tunnel exit extremely quickly and reliably, which can be used, for example, to switch on the headlights of the motor vehicle 1 or to switch off the headlights of the motor vehicle 1. Figure 4A second example of a time history 15, 16 of measurement data in the above-described manner is illustrated in the diagram in Fig. 2. Here, the time history 15 is again recorded by the headlight 2, and the time history 16 is recorded by the tail light 3. It can be seen that, according to the course of change 15, the measured brightness drops at a time 17 to a new, continuously lower value. When the motor vehicle 1 drives into a tunnel, initially the front portion drives in, and subsequently the rear portion drives in, so that a corresponding drop in brightness is also found in the course of change 16 at a later time 18. There are thus correlated brightness changes which are separated in time by a time value 19. If there is also a current speed value of the motor vehicle 1 in the control device 10, it is additionally possible to check whether the time value 19 corresponds to an expected value which is predicted on the basis of the current speed, in addition to determining the actual entry into the tunnel on the basis of the time sequence. According to these correlations, the tunnel entry and the tunnel exit can be determined more quickly and more robustly.

[0041] The control device 10 uses the determined ambient brightness information to operate the vehicle system 20, wherein, in the present exemplary case, a lighting system 21 and a vehicle system 22 for at least partially automated driving of the motor vehicle 1 are shown. For the lighting system 21, a passing light switching is implemented, so that, for example, when driving into a tunnel, a low beam can be activated as an operating mode, or when a sufficient overall ambient brightness is reached in the morning, a daytime running light can be switched on. In other words, the operating mode of the lighting system 21 is selected on the basis of the ambient brightness information. For the vehicle system 22, the vehicle system can, for example, recognize a certain ambient brightness situation as a preference of the driver for at least partially automated driving, and take corresponding measures.

[0042] Finally, Figure 5 A flow diagram of one embodiment of the method according to the application is shown. Here, in a step S1, measurement data is recorded by measuring the light emitting device 5. In a step S2, the measurement data is evaluated by the control device 10 for determining the ambient brightness information. To this end, the control device 10 can comprise, for example, an evaluation unit. The ambient brightness information is then used in a step S3 to operate at least one of the vehicle systems 20. This can be done by means of a corresponding control unit.

Claims

1. A motor vehicle (1) having a plurality of outwardly pointing light-emitting devices (5), the light-emitting devices including at least one measuring light-emitting device (5), the measuring light-emitting device having at least one light source, wherein, The light source of the measuring light-emitting device (5) can be used to emit light and measure incident light. The motor vehicle (1) also has a control device (10) designed to evaluate the measurement data determined in the measurement mode of the light source. The control device (10) is designed to determine ambient brightness information describing the ambient brightness around the motor vehicle (1) from the measurement data and drive at least one vehicle system (20) in the use of the ambient brightness information. The motor vehicle (1) has at least two measuring light-emitting devices (5) arranged at different positions and / or pointing in different directions on the motor vehicle (1). The control device (10) is designed to combine and analyze the measurement data of each measuring light-emitting device (5) when determining the ambient brightness information.

2. The motor vehicle according to claim 1, characterized in that, The light source is a light-emitting diode (9).

3. The motor vehicle according to claim 1 or 2, characterized in that, The control device (10) is designed to take into account the orientation of the light source of the light-emitting device (5) and / or the time history (11, 12, 15, 16) of the measurement data of the light source of the light-emitting device (5) when determining ambient brightness information and / or the light emitted by the light source of the light-emitting device (5) or another light source.

4. The motor vehicle according to claim 3, characterized in that, The control device (10) is designed to evaluate the time history of the measurement data (11, 12, 15, 16) to detect tunnel entrances and / or tunnel exits, and / or to evaluate the measurement data in a statistical manner within a time window that includes multiple measurement moments.

5. The motor vehicle according to any one of the preceding claims, characterized in that, The plurality of measuring light-emitting devices (5) have at least two of the following orientations: - Pointing to the area in front of the motor vehicle (1), - Pointing to the rear space of the motor vehicle (1), and - Pointing to the side, And / or the positions of at least two of the plurality of measuring light-emitting devices (5) are spaced apart from each other along the longitudinal direction of the vehicle, and / or the control device (10) is designed to perform a mutual reliability check on the measurement data of different measuring light-emitting devices (5) related to ambient brightness in a combined analysis.

6. The motor vehicle according to any one of the preceding claims, characterized in that, The control device (10) is designed to perform correlation analysis on the time histories (11, 12, 15, 16) of different measuring light-emitting devices (5) when detecting tunnel entrances and tunnel exits, and / or take into account the position and / or orientation of the measuring light-emitting devices (5).

7. The motor vehicle according to any one of the preceding claims, characterized in that, The vehicle system (20) driven by ambient brightness information is a lighting system (21) that includes at least a portion of the light-emitting device (5) of the motor vehicle (1), the lighting system including the headlights (2) of the motor vehicle (1), and the control device (10) switching the driving lights for the lighting system when using ambient brightness information.

8. The motor vehicle according to any one of the preceding claims, characterized in that, The at least one measuring light-emitting device (5) includes the headlight (2) and / or taillight (3) of the motor vehicle (1).

9. A method for operating a motor vehicle (1) according to any one of the preceding claims, wherein, By measuring the light source of the light-emitting device (5) in the measurement mode, the control device (10) detects the measurement data describing the incident light, determines the ambient brightness information describing the ambient brightness around the motor vehicle (1) from the measurement data, and drives at least one vehicle system (20) in the case of using the ambient brightness information, wherein, when determining the ambient brightness information, the control device (10) combines and analyzes the measurement data of each light-emitting device (5).

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