FORM 2
The Patent Act 1970
(39 OF 1970)
AND
THE PATENT RULES, 2005
COMPLETE SPECIFICATION (See Section 10; rule 13)
TITLE OF THE INVENTION
“METHOD AND LIGHTING CONTROL SYSTEM TO CONTROL LIGHT BEAM OF VEHICLE DURING BEAM FAILURE EVENT”
APPILICANT(S)
TATA MOTORS LIMITED
an Indian company
having its registered office at Bombay house,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001,
Maharashtra, INDIA.
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
[0001] The present disclosure relates to a lighting control system for a vehicle, and more particularly relates to a lighting control system to control a light beam of a vehicle by automatically configuring a high light beam mode upon detection of a beam failure event with a low light beam mode and vice versa.
BACKGROUND OF THE INVENTION
[0002] Modern automotive vehicles variety of headlamps that are typically
controlled to alternately generate a low light beam for short distance and a high light beam for long distance. The low light beam is provided in the areas where street light or likewise illuminated place already exists, whereas the high light beam is provided in highways or such roads where provision of street lights does not exists. Failure of these headlamps even for a small duration of time may critically effect the driving experience. Specifically, when the vehicle is at a high speed, failure of the low light beam or the high light beam even for few seconds may lead to situations prone to accidents.
[0003] Conventional modern vehicles comes with an Automatic High
Beam (AHB) control system to maximize the use of high beam road illumination and control exterior lighting functions when appropriate. FIG. 1a illustrates mode of operation of control system (100) during normal condition, according to prior art. The control system (100) includes a light source (102) connected to an Electronic control unit (104). The light source (102) includes a high beam head lamp (102a) and a low beam head lamp (102b). The Electronic control unit (104) is connected to an input terminal (106) to receive input associated with the light source (102). During the normal condition, when the input terminal (106) indicates that the high beam is to be switched ON, the electronic control unit (104) activates both the

high beam head lamp (102b) and the low beam head lamp (102a) simultaneously. However, when the input terminal (106) indicates that the low beam is to be switched ON (106), only the low beam head lamp (102a) remains activated as shown in the FIG. 1a.
[0004] FIG. 1b illustrates mode of operation of control system (100) during
failure condition, according to prior art. When the input terminal (106) indicates that only the low beam is to be switched ON, if the low beam filament burns out or the low beam relay fails then the high beam lamp (102b) cannot be activated automatically as there is no failure feedback to the control system (100) as shown in the FIG. 1b. During such failure condition, the driver has to manually switch ON the high beam lamp (102b) as soon as possible. This results in accidents on road due to lack of visibility on the road.
[0005] Accordingly, there is a need of system that overcomes the above mentioned problem.
OBJECT OF THE INVENTION
[0006] The principal object of the embodiments herein is to provide a lighting control system to control a light beam of a vehicle by automatically configuring a high light beam mode upon detection of a beam failure event with a low light beam mode and vice versa.
[0007] Another object of the embodiments herein is to provide an optical sensor inside a lamp chamber to detect the failure event and transmit signal over Local interconnect network (LIN) with respect to operation or non-operation of a low beam of a lamp of the vehicle to an electronic control unit.

[0008] Yet another object of the embodiments herein is to automatically diagnose the non-operation of the sensor. Sensor circuits for open circuit, short to ground and short to battery can be diagnosed.
SUMMARY OF THE INVENTION
[0009] In one aspect object is satisfied by providing a lighting control system to control a light beam of a vehicle, the lighting control system includes a light source connected to an electronic control unit. The light source is connected to front of the vehicle and configured to produce a light beam in a first mode. The light source includes an optical sensor configured to measure a status information of the light beam produced in the first mode. The electronic control unit is configured to receive the measured status information of the light beam produced in the first mode from the optical sensor, detect a beam failure event associated with the light beam produced in the first mode based on the measured status information, and configure the light source to produce a light beam in a second mode in response to detecting the beam failure event associated with the light beam produced in the first mode. Further, the electronic control unit is configured to provide a notification about the production of the light beam in the second mode.
[0010] In an embodiment, the first mode is a high light beam mode and the second mode is a low light beam mode.
[0011] In an embodiment, the first mode is a low light beam mode and the second mode is a high light beam mode.
[0012] In an embodiment, the optical sensor includes a DC Current transformer, a light beam filament providing a hardwired feedback signal from, a shunt on a light beam circuit, a thermal sensor, and an optical sensor.

[0013] In an embodiment, the light source includes a first lamp (102a) to generate the light beam in the first mode and a second lamp (102b) to generate the light beam in the second mode.
[0014] In an embodiment, the optical sensor and the electronic control unit is connected and communicates with each other over a Local interconnect network (LIN).
[0015] In an embodiment, the optical sensor transmit a signal corresponding to the status information of the light beam produced in the first mode over the LIN.
[0016] In an embodiment, the status information indicates one of operation and non-operation of the light beam produced in the first mode.
[0017] In one aspect object is satisfied by providing a method implemented by a lighting control system for controlling a light beam of a vehicle. The method includes producing the light beam in a first mode by a light source, measuring a status information of the light beam produced in the first mode using optical sensor, detecting a beam failure event associated with the light beam produced in the first mode based on the measured status information, and configuring the light source to produce a light beam in a second mode in response to detecting the beam failure event associated with the light beam produced in the first mode. Further, the method includes providing a notification about the production of the light beam in the second mode.
[0018] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that

the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
BRIEF DESCRIPTION OF DRAWINGS
[0019] The proposed lighting control system and method thereof are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0020] FIG. 1a illustrates mode of operation of control system during normal condition, according to prior art;
[0021] FIG. 1b illustrates mode of operation of control system during failure condition, according to prior art;
[0022] FIG. 2 illustrates various components of a lighting control system to control a light beam of a vehicle, according to embodiments as disclosed herein;
[0023] FIG. 3a illustrates an example mode of operation of proposed lighting control system during normal condition, according to embodiments as disclosed herein;

[0024] FIG. 3b illustrates an example mode of operation of proposed lighting control system during failure condition, according to embodiments as disclosed herein; and
[0025] FIG. 4 illustrates a method for controlling a light beam of a vehicle, according to embodiments as disclosed herein.
DETAILED DESCRIPTION OF THE INVENTION
[0026] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. Also, the various embodiments described herein are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments. The term “or” as used herein, refers to a non-exclusive or, unless otherwise indicated. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein can be practiced and to further enable those skilled in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0027] The accompanying drawings are used to help easily understand various technical features and it should be understood that the embodiments presented herein are not limited by the accompanying drawings. As such, the present disclosure should be construed to extend to any alterations, equivalents and substitutes in addition to those which are particularly set out in the accompanying drawings. Although the terms first, second, etc. may be used herein to describe

various elements, these elements should not be limited by these terms. These terms are generally only used to distinguish one element from another.
[0028] Referring now to the drawings, and more particularly to FIGS. 2-4, there are shown preferred embodiments.
[0029] FIG. 2 illustrates various components of a lighting control system (100) to control a light beam of a vehicle, according to embodiments as disclosed herein. The lighting control system (100) includes a light source (102) connected to a front of the vehicle and an electronic control unit (104) connected to the light source (102).
[0030] The light source (102) includes a first lamp (102a) to generate the light beam in the first mode and a second lamp (102b) to generate the light beam in the second mode. In an embodiment, the first mode is a high light beam mode and the second mode is a low light beam mode. In another embodiment, the first mode is a low light beam mode and the second mode is a high light beam mode.
[0031] In an embodiment, the first lamp (102a) can be a low light lamp to produce the light beam in the low light beam mode and the second lamp (102b) can be a high light lamp to produce the light beam in the high light beam mode. Similarly in another embodiment, the first lamp (102a) can be a high light lamp to produce the light beam in the high light beam mode and the second lamp (102b) can be a low light lamp to produce the light beam in the low light beam mode.
[0032] Further, the light source (102) is configured to produce the light beam in several different modes including conventional low-beam and high-beam states. The light source (102) can also be operated as daytime running lights, and additionally as super-bright high light beams in those countries where they are

permitted. The headlamp brightness may also be continuously varied between the low, high, and super-high states. Examples of the lighting source include but not limited to light source (102) headlamps, tail lights, foul weather lights such as fog lights, brake lights, center-mounted stop lights (CHMSLs), turn signals, back¬up lights, cargo lights, puddle lights, license plate illuminators, etc.
[0033] In an embodiment, the first lamp (102a) includes one or more sensors (108) and a Local interconnect network (LIN) (110). The sensors (108) is configure to detect a status information of the light beam produced in the first mode by the first lamp (102a) and transmit a signal corresponding to the status information of the light beam produced in the first mode over the LIN (110). The status information indicates one of operation and non-operation of the light beam produced in the first mode. The optical sensor (108) is placed inside a chamber of the light source (102) or in proximity to the light source (102) as illustrated in FIG. 2. Examples of other sensors alternatives to optical sensor (108) includes but not limited to a DC Current transformer, a light beam filament providing a hardwired feedback signal from, a shunt on a light beam circuit, a thermal sensor, and an optical sensor.
[0034] The electronic control unit (104) is connected to the light source (102) and the optical sensor (108) and communicates with the optical sensor (108) over the LIN (110). Generally the LIN (110) has several advantages over any hardwired signal feedback. Having a LIN communication in place can reduce calibration efforts of the electronic control unit (104). A LIN communication negates the chances of introducing electrical noise to the hardwire output of the optical sensor (108).
[0035] The electronic control unit (104) is configured to receive the measured status information of the light beam produced in the first mode from the

optical sensor (108) and detect a beam failure event associated with the light beam produced in the first mode by the first lamp (102a) based on the measured status information. In response to detecting the beam failure event associated with the light beam produced in the first mode by the first lamp (102a), the electronic control unit (104) configures first lamp (102b) of the light source (102) to produce a light beam in a second mode. Further, the electronic control unit (104) is configured to provide a notification about the production of the light beam in the second mode. Furthermore, the electronic control unit (104) is configured to automatically diagnose the non-operation of the sensor.
[0036] FIG. 3a illustrates an example mode of operation of proposed lighting control system (100) during normal condition, according to embodiments as disclosed herein. In this example, the first lamp (102a) is considered as low light lamp (102a) and the second lamp (102b) is considered as high light lamp (102b). During the normal condition, when the input terminal (106) indicates that the high beam is switched ON, the electronic control unit (104) activates both the high beam head lamp (102b) and the low beam head lamp (102a) simultaneously and when the input terminal (106) indicates that the low beam is switched ON, the electronic control unit (104) activates only the low beam head lamp (102a). However, unlike the conventional control system, when the input terminal (106) indicates that the low beam is to be switched ON (106) and the optical sensor (108) detects that low beam head lamp (102a) is not turned ON the high beam head lamp (102b) is automatically activated as shown in the FIG. 3a.
[0037] FIG. 3b illustrates an example mode of operation of proposed lighting control system (100) during failure condition, according to embodiments as disclosed herein. When the input terminal (106) indicates that only the low beam lamp (102a) is switched ON, the electronic control unit (104) receives signal corresponding to the current status of the low beam lamp (102a) measured by the

optical sensor (108) and determine whether the failure event is detected based on the current status. In response to detecting the failure of the low beam lamp (102a), the electronic control unit (104) automatically configures the high beam lamp (102b) cannot be activated as shown in the FIG. 3b. Hence during the failure condition, the driver need not to manually switch ON the high beam lamp (102b). This increases the overall driving experience of the user and also decreases the changes of accidents due lamp failures.
[0038] When the low beam turns ON, it generally takes few seconds for the chamber to get heated up. Thus, based on the thermal sensor input only, the electronic control unit (104) cannot determine whether the lamp is ON or OFF, in the initial few seconds. So the proposed invention uses the optical sensor (108) which can sense directly whether the low beam lamp is ON. The electronic control unit (104) will ignore the low temperature input from the thermal sensors in the initial few seconds if the optical sensor indicates that low beam lamp is ON.
[0039] Although the optical sensor (108) illustrates as being mounted insider or near the light source, but those skilled in the art will recognize that the optical sensor (108) could be mounted at other locations that provide the sensor (108) to appropriately measure the status of the lamps.
[0040] FIG. 4 illustrates a method for controlling a light beam of a vehicle, according to embodiments as disclosed herein. At step 402, the method includes producing a light beam in a first mode by a light source (102). In an embodiment, the first mode is a low light beam mode and the second mode is a high light beam mode. In another embodiment, the first mode is a high light beam mode and the second mode is a low light beam mode.

[0041] At step 404, the method includes measuring a status information of the light beam produced in the first mode using the optical sensor (108) and transmit the status information to the electronic control unit (104). The optical sensor (108) transmits a signal corresponding to the status information of the optical sensor (108) to the electronic control unit (104) over the LIN (110).
[0042] At step 406, the method includes receiving the signal corresponding to the status information of the light beam produced in the first mode by the electronic control unit (106) over the LIN (110). The status information indicates one of operation and non-operation of the light beam produced in the first mode.
[0043] At step 408, the method includes determining whether a beam failure event associated with the light beam produced in the first mode is detected based on the measured status information. When the status information indicates that the light source (102) is non-operable then the electronic control unit (106) detects the beam failure event.
[0044] In response to detecting the beam failure event associated with the light beam produced in the first mode, at step 408, the method includes configuring the light source (102) to produce a light beam in a second mode. Further, at step 410, the method includes providing a notification about the production of the light beam in the second mode and at step 412, the method includes automatically diagnosing the light source upon detecting the failure event.
[0045] Although the present invention primarily addresses the control of the vehicle headlamps, but those skilled in the art will recognize that proposed lighting control system and method thereof can be used for controlling the tail lights and foul weather lights. Indeed, the present invention is generally applicable to for controlling any exterior lighting on the vehicle.

[0046] The foregoing description of the specific embodiments will so fully
reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
[0047] List to reference numerals:

Sr. No. Description
100 Lighting control system
102 Light Source
102a first lamp
102b second lamp
104 electronic control unit
106 Input Terminal
108 optical sensor
110 Local interconnect network

We Claim:
1. A lighting control system (100) to control a light beam of a vehicle, the lighting
control system (100) comprises:
a light source (102) connected to a front of the vehicle and configured to produce a light beam in a first mode, wherein the light source (102) comprises at least one optical sensor (108) configured to measure a status information of the light beam produced in the first mode; and
an electronic control unit (104), connected to the light source (102) and the at least one optical sensor (108), configured to:
receive the measured status information of the light beam produced in the first mode from the at least one optical sensor (108),
detect a beam failure event associated with the light beam produced in the first mode based on the measured status information, and
configure the light source (102) to produce a light beam in a second mode in response to detecting the beam failure event associated with the light beam produced in the first mode.
2. The lighting control system (100) as claimed in claim 1, wherein the electronic control unit (104) is configured to provide a notification about the production of the light beam in the second mode.
3. The lighting control system (100) as claimed in claim 1, wherein the first mode is a high light beam mode and the second mode is a low light beam mode.
4. The lighting control system (100) as claimed in claim 1, wherein the first mode is a low light beam mode and the second mode is a high light beam mode.

5. The lighting control system (100) as claimed in claim 1, wherein the at least one optical sensor (108) comprises a DC Current transformer, a light beam filament providing a hardwired feedback signal from, a shunt on a light beam circuit, a thermal sensor, and an optical sensor.
6. The lighting control system (100) as claimed in claim 1, wherein the light source (102) comprises a first lamp (102a) to generate the light beam in the first mode and a second lamp (102b) to generate the light beam in the second mode.
7. The lighting control system (100) as claimed in claim 1, wherein the at least one optical sensor (108) and the electronic control unit (104) is connected and communicates with each other over a Local interconnect network (LIN) (110).
8. The lighting control system (100) as claimed in claim 7, wherein the at least one optical sensor (108) transmit a signal corresponding to the status information of the light beam produced in the first mode over the LIN (110).
9. The lighting control system (100) as claimed in claim 1, wherein the status information indicates one of operation and non-operation of the light beam produced in the first mode.
10. A method implemented by a lighting control system (100) for controlling a
light beam of a vehicle, the method comprises:
producing the light beam in a first mode by a light source (102);
measuring a status information of the light beam produced in the first mode using at least one optical sensor (108);
detecting a beam failure event associated with the light beam produced in the first mode based on the measured status information; and

configuring the light source (102) to produce a light beam in a second mode in response to detecting the beam failure event associated with the light beam produced in the first mode.
11. The method as claimed in claim 10, wherein the method comprises providing a notification about the production of the light beam in the second mode.
12. The method as claimed in claim 10, wherein the first mode is a high light beam mode and the second mode is a low light beam mode.
13. The method as claimed in claim 10, wherein the first mode is a low light beam mode and the second mode is a high light beam mode.
14. The method as claimed in claim 10, wherein the at least one optical sensor (108) comprises a DC Current transformer, a light beam filament providing a hardwired feedback signal from, a shunt on a light beam circuit, a thermal sensor, and an optical sensor.
15. The method as claimed in claim 10, wherein the light source (102) comprises a first lamp (102a) to generate the light beam in the first mode and a second lamp (102b) to generate the light beam in the second mode.
16. The method as claimed in claim 10, wherein the at least one optical sensor (108) and the electronic control unit (104) is connected and communicates with each other over a Local interconnect network (LIN) (110).
17. The method as claimed in claim 16, wherein the at least one optical sensor (108) transmit a signal corresponding to the status information of the light beam produced in the first mode over the LIN (110).

18. The method as claimed in claim 10, wherein the status information indicates one of operation and non-operation of the light beam produced in the first mode.