METHOD FOR DETECTING A FAILURE IN A SOLID-STATE LIGHT SOURCE OF AN AUTOMOTIVE LIGHTING DEVICE AND AUTOMOTIVE ARRANGEMENT

Abstract

This invention provides a method for detecting a failure in a solid-state light source of an automotive lighting device. This method provides an estimated temperature profile for the lighting device, measures an actual temperature profile of the lighting device and compares the estimated temperature profile with the actual temperature profile in order to detect a difference between them.

Claims

1. A method for detecting a failure in a solid-state light source of an automotive lighting device, the method comprising: providing an estimated temperature profile for the lighting device; measuring an actual temperature profile of the lighting device; and comparing the estimated temperature profile with the actual temperature profile in order to detect a difference between them.

2. The method according to claim 1, wherein providing the estimated temperature profile includes: checking the data of at least one temperature sensor; and/or checking the data of one vehicle speed sensor; and/or checking the activation of lighting functionalities; and use at least one of the previous values to estimate the temperature of the lighting device.

3. The method according to claim 2, wherein using the values to estimate the temperature of the lighting device includes the use of a machine learning algorithm.

4. The method according to claim 1, further comprising: activate a first lighting functionality only in a section of the lighting device; measuring a second actual temperature profile in the lighting device; measuring a third actual temperature profile in the section of the lighting device; and compare the estimated temperature profile with the second actual temperature profile and with the third actual temperature profile.

5. The method according to claim 4, further comprising: perform a second lighting functionality in the section of the lighting device; measuring a fourth actual temperature profile in the lighting device; measuring a fifth actual temperature profile in the section of the lighting device; and compare the estimated temperature profile with the fourth actual temperature profile and with the fifth actual temperature profile.

6. The method according to claim 5, wherein the first lighting functionality is one of Adaptive Driving Beam, hazard warning or Dynamic Bending Light and the second lighting functionality is different from the first lighting functionality and is one of Adaptive Driving Beam, hazard warning or Dynamic Bending Light.

7. The method according to claim 4, wherein activating a first lighting functionality is performed subsequently in more than one section of the lighting device.

8. The method according to claim 7, wherein the section of the lighting device is chosen by an AI algorithm.

9. (canceled)

10. (canceled)

11. An automotive lighting arrangement comprising: an automotive lighting device including a matrix arrangement of solid-state light sources, a plurality of auxiliary sensors configured to provide some device data, a plurality of temperature sensors, and a control unit, with the control unit configured to: provide an estimated temperature profile for the lighting device; measure an actual temperature profile of the lighting device; and compare the estimated temperature profile with the actual temperature profile in order to detect a difference between them.

12. The automotive arrangement according to claim 11, wherein the matrix arrangement includes at least 2000 solid-state light sources.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0044] To complete the description and in order to provide for a better understanding of the invention, a set of drawings is provided. Said drawings form an integral part of the description and illustrate an embodiment of the invention, which should not be interpreted as restricting the scope of the invention, but just as an example of how the invention can be carried out. The drawings comprise the following figures:

[0045] FIG. 1 shows a general perspective view of an automotive lighting device and a sensor comprised in an automotive arrangement according to the invention.

[0046] FIGS. 2a, 2b and 2c show three different temperature measurements in a headlamp.

[0047] FIGS. 3a, 3b and 3c show three different temperature measurements in a headlamp when an ADB lighting functionality is activated.

[0048] FIGS. 4a, 4b and 4c show three different temperature measurements in a headlamp when a HW lighting functionality is activated.

DETAILED DESCRIPTION OF THE INVENTION

[0049] To complete the description and in order to provide for a better understanding of the invention, a set of drawings is provided. Said drawings form an integral part of the description and illustrate an embodiment of the invention, which should not be interpreted as restricting the scope of the invention, but just as an example of how the invention can be carried out. The drawings comprise the following figures:

[0050] FIG. 1 shows a general perspective view of an automotive lighting device and a sensor comprised in an automotive arrangement according to the invention.

[0051] FIGS. 2a, 2b and 2c show three different temperature measurements in a headlamp.

[0052] FIGS. 3a, 3b and 3c show three different temperature measurements in a headlamp when an ADB lighting functionality is activated.

[0053] FIGS. 4a, 4b and 4c show three different temperature measurements in a headlamp when a HW lighting functionality is activated.

[0054] In these figures, the following reference numbers have been used: [0055] 1 Headlamp [0056] 2 LED [0057] 3 Control unit [0058] 4 Auxiliary sensors [0059] 5 Temperature sensors [0060] 11 Estimated temperature profile [0061] 12 Actual temperature profile [0062] 100 Automotive vehicle

[0063] The example embodiments are described in sufficient detail to enable those of ordinary skill in the art to embody and implement the systems and processes herein described. It is important to understand that embodiments can be provided in many alternate forms and should not be construed as limited to the examples set forth herein.

[0064] Accordingly, while embodiment can be modified in various ways and take on various alternative forms, specific embodiments thereof are shown in the drawings and described in detail below as examples. There is no intent to limit to the particular forms disclosed. On the contrary, all modifications, equivalents, and alternatives falling within the scope of the appended claims should be included.

[0065] FIG. 1 shows a general perspective view of a headlamp 1 and a plurality of sensors comprised in an automotive arrangement according to the invention.

[0066] This headlamp 1 is installed in an automotive vehicle 100 and comprises [0067] a matrix arrangement of LEDs 2, intended to provide a light pattern; [0068] a control unit 3 to perform a thermal analysis of the operation of the LEDs 2; and [0069] a plurality of auxiliary sensors 4 intended to provide device data [0070] a plurality of temperature sensors 5 intended to provide temperature measurements of different sections of the matrix arrangement.

[0071] This matrix configuration is a high-resolution module, having a resolution greater than 2000 pixels. However, no restriction is attached to the technology used for producing the projection modules.

[0072] The control unit 3, previously to its installation in the automotive headlamp 1, has undergone a training process to provide an estimated temperature profile for different sections of the headlamp, depending on the data received by the auxiliary sensors 4. This control unit has undergone a training process to be able to provide accurate temperature estimation profiles.

[0073] FIGS. 2a, 2b and 2c show three different temperature measurements in a headlamp.

[0074] First one, illustrated in FIG. 2a, refers to the temperature evolution in an overall approach of the headlamp. Continuous line shows an estimated temperature profile 11, which has been estimated taking into account the physical features of the headlamp and environmental conditions of the vehicle (speed, exterior temperature, presence of other vehicle, activation of different lighting functionalities in the headlamp . . . ). This temperature estimation has also undergone an AI algorithm, to provide an even more accurate estimation.

[0075] Dashed line shows the real measured temperature 12, which is provided by temperature sensors located in the headlamp.

[0076] As may be seen in this FIG. 2a, there is a slight deviation of the real measured temperature against the ideal estimated temperature.

[0077] FIGS. 2b and 2c show these temperature measurements in different sections of the headlamp. FIG. 2b shows a section where the temperature evolution perfectly matches with the temperature estimation, so, in this section, the LEDs work properly. However, FIG. 2c shows a section where the temperature evolution shows a deviation with respect to the estimated one.

[0078] Since this is a slight deviation, this indicates that there is a possibility of a LED failure, but this should be confirmed with a more detailed diagnosis.

[0079] To do this detailed diagnosis, a particular lighting functionality, such as ADB, DBL or HW, is activated. These lighting functionalities have the particular feature of isolating a particular section of the LEDs and performing a totally different light pattern in this section.

[0080] FIGS. 3a, 3b and 3c show the temperature evolution in different sections of the headlamp when an ADB functionality is activated concerning a particular section of the LED arrangement.

[0081] This ADB functionality is normally used to avoid glaring a vehicle coming in the opposite lane, or to avoid glaring a vehicle which is circulating in the same lane, but a few meters ahead.

[0082] In this method, this functionality is used to check if the temperature estimation is correct and to confirm if the section which produced the temperature deviation could be defective. The ADB functionality is used in FIGS. 3a, 3b and 3c to obscure the allegedly defective section of the LED arrangement of FIG. 2c. FIG. 3a shows the temperature estimation profile of the whole headlamp when the ADB function is applied to the problematic section of FIG. 2c.

[0083] Since the problematic section is not working, all the active LEDs are working properly and therefore the actual measured temperature 12 coincides with the estimated temperature profile 11.

[0084] When applied to the problematic section, in FIG. 3c, since it is turned off due to the ADB functionality, the temperature in this section also matches with the estimated one.

[0085] When applied to a LED section different from the problematic one, as shown in FIG. 3b, the actual measured temperature profile also matches with the estimated one, so there are no more problematic sections.

[0086] In FIGS. 4a, 4b and 4c, an additional method is used to isolate and identify the failing LEDs.

[0087] A HW functionality is activated in the problematic section.

[0088] FIG. 4a shows the temperature estimation profile of the whole headlamp when the HW functionality is operated in the problematic section. As in the case of FIG. 2a, there is a deviation in the actual measured temperature profile 12 with respect to the estimated temperature profile 11, which means that some failure may be taking place.

[0089] FIG. 4b shows the temperature profile in a section which is far from the problematic section. In this figure, the actual measure temperature profile 12 matches with the estimated temperature profile 11, so there is no malfunctioning of this section.

[0090] FIG. 4c shows the temperature profiles in the problematic section. Since the use of the HW functionality is a highly demanding one, the failing LEDs cause a temperature drop when time advances, providing an evidence of the failure of some LEDs in this section.

[0091] Hence, this method is able to detect and isolate a particular section of the LED arrangement where the failure takes place.