HIGH-PERFORMANCE LIGHTING FOR MOTOR VEHICLE ACCIDENTS SIMULATION SETUP

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a lighting unit and to the use of a plurality of such lighting units in a lighting device for a motor vehicle accident simulation arrangement. BACKGROUND

[0002] Methods and devices for testing the effects of a motor vehicle accident have long been known, commonly referred to as crash tests and crash test systems. In such a crash test, a motor vehicle is driven to a predefined collision point using its own or a third-party drive. The moment of the collision is recorded using special high-speed cameras, which typically have recording frequencies between 1,000 and 2,000 frames per second to capture as much detail as possible, allowing the effects of the collision to be analyzed very precisely.

[0003] The use of such high-speed cameras with their short exposure times requires intensive and homogeneous illumination of the entire vehicle at the time of the collision. For this purpose, a lighting device is provided, consisting of a plurality of lighting units, which are usually movably mounted on a rail suspended from a hall ceiling. Each of these lighting units directs a beam of radiation onto a section of the vehicle. The goal is to achieve the most spatially homogeneous illumination possible of the entire area of ​​the vehicle.

[0004] The lighting units used to illuminate the motor vehicle during image recording must generate a very high luminous flux so that the motor vehicle can be illuminated to a sufficient extent, in particular in order to be able to meet the above-mentioned requirements of the high-speed cameras.

[0005] The document US 2015 / 197182 A1 describes a lighting device with a control circuit, an acceleration detector that cooperates with the control circuit, and a plurality of light sources that cooperate with the control circuit and are controlled by the control circuit to operate with an illuminance that varies between a first illuminance that is not equal to zero and a second illuminance that is not equal to zero.

[0006] The document US 2013 / 229518 A1 describes an illumination system comprising a light source, a two-dimensional on-passive infrared imager and a controller, wherein the light source can provide at least two illumination levels. SUMMARY

[0007] A first aspect of the disclosure relates to a lighting unit according to claim 1.

[0008] A second aspect of the disclosure relates, according to claim 8, to a use of a plurality of lighting units according to the first aspect in a lighting device for a simulation arrangement for motor vehicle accidents.

[0009] Those skilled in the art will recognize additional features and advantages upon reading the following detailed description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying drawings illustrate embodiments and, together with the description, serve to explain principles of the present disclosure as well as details of the embodiments. Fig. 1 shows a schematic plan view of a simulation setup for motor vehicle accidents. Fig. 2 shows a schematic block diagram of an embodiment of a lighting unit according to the first aspect. Fig. 3 shows a schematic block diagram of an embodiment of a lighting unit according to the first aspect, in which the lighting unit has a plurality of groups of LEDs and respective associated power regulators as well as a light source control device which is connected to each of the power regulators. Fig. 4 shows a plan view of a light source of an embodiment of a lighting unit according to the first aspect, wherein the light source has a matrix-like arrangement of LEDs. Fig. 5 shows a schematic block diagram of an embodiment of a lighting device having a number of n lighting units Fig. 6 shows an example current-time diagram illustrating the time dependence of the current supplied to the LEDs before, during and after a crash test. DETAILED DESCRIPTION

[0011] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the present disclosure may be practiced. In this regard, directional terminology such as "top," "bottom," "front," "back," "fore," "rear," etc., is used with reference to the orientation of the described figure(s). Since components of embodiments of the present disclosure can be positioned in a number of different orientations, the directional terminology is for the purpose of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present disclosure.The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present disclosure is defined by the appended claims.

[0012] To the extent that the following description, the patent claims, or the drawings state that circuit elements are "connected," "electrically connected," or "electrically coupled" to one another, this may mean that the elements mentioned are directly coupled to one another, i.e., without any additional elements in between. However, it may also mean that the elements mentioned are not directly coupled to one another and that additional elements are coupled between the elements mentioned. Where identical reference numerals are used in the figures, these refer to identical or functionally equivalent elements, so that in these cases the description of these elements is not repeated.

[0013] Fig. 1 shows the essential components of a crash test facility in a schematic and highly simplified form. The chosen representation is merely intended to clarify the starting point for the present disclosure. A crash test facility 10 has a collision point 1, a lighting device 2, and a plurality of high-speed cameras (not shown) intended to record the moment of impact of a motor vehicle 3 on the collision point 1. The collision point 1 can be a stationary, immovable obstacle or another vehicle. The lighting device 2 can have a plurality of lighting units 2.1, which are fastened, for example, to a rail 2.2, which in turn is suspended from the hall ceiling. Three lighting units 2.1 are shown by way of example. Each of the lighting units 2.1 emits a radiation beam 2.11 in the direction of the motor vehicle 3. The lighting units 2.1 may, for example, contain halogen gas discharge lamps operated with special ballasts or light-emitting diodes (LEDs), in particular white light LEDs.

[0014] Fig. 2 shows a schematic block diagram of an embodiment of a lighting unit according to the first aspect. A lighting unit 21 according to the first aspect comprises a light source 21.1, at least one power regulator 21.2, in particular a current regulator, connected to the light source 21.1, and an input 21.4 for supplying a start signal. An output of the power regulator 21.2 is connected to the light source 21.1 via a line 21.5. The light source 21.1 can comprise a plurality of light-emitting diodes (LEDs), in particular white-light LEDs 21.11.

[0015] The power regulator 21.2 is configured to control the supply of electrical power, in particular electrical current, to the light source 21.1 such that, upon receipt of the start signal, the supplied electrical power is increased from a first value to a second value, wherein the first value is different from zero and the second value is greater than the first value. The power regulator 21.2 can draw the electrical power or the electrical current from the public power grid (not shown). The light source 21.1 is then supplied with electrical current according to the first value or the second value via the line 21.5. As will be seen, each lighting unit 21 can also contain a plurality of power regulators 21.2.

[0016] The second value can, for example, be a maximum value of the electrical power that can be supplied to the light source and can be designated as 100%. Such a maximum value of the electrical power can depend, for example, on the thermal load capacity of the LEDs 21.11 and / or the performance of the power regulator 21.2. Irrespective of this, the first value of the electrical power can be in a range between 10% and 50%, in particular between 20% and 40%, preferably approximately 30%, of the second value, i.e., approximately the maximum value of the electrical power, in particular the electrical current.

[0017] According to one example of the lighting unit according to the first aspect, the light source 21.1 comprises a plurality of light-emitting diodes (LEDs) 21.11, in particular white-light LEDs, which can be arranged in the form of a matrix. Alternatively, the light source 21.1 can also be a halogen gas discharge lamp.

[0018] As in Fig. 4 As shown, the matrix-shaped arrangement of LEDs 21.11 can be mounted within a flat rectangular housing 21.3 having four side walls and a rear wall (not visible).

[0019] Fig. 3 shows a block diagram of a lighting unit according to the first aspect, which has a plurality of power controllers, each of which is connected to a group of LEDs. The lighting unit 21 of the Fig. 3 comprises a plurality of groups 21.10 of LEDs 21.11 and a corresponding plurality of power regulators 21.20, each group 21.10 of LEDs 21.11 being connected to and controlled by one of the power regulators 21.20. Each of the power regulators 21.20 can be configured like the power regulator 21.2 of the Fig. 1 . Referring to Fig. 4 The groups 21.10 of LEDs 21.11 can be formed in various ways. For example, the groups 21.10 can be several adjacent or subordinate rows or columns of the matrix of LEDs 21.11. Alternatively, the groups 21.10 can also be formed from submatrices of the entire matrix, for example, by dividing the entire matrix into four quadrants.

[0020] A light source 21.1 can, for example, have a total of 150 to 250, in particular approximately 200 LEDs, which are divided into blocks of 15-20 LEDs, in particular approximately 18 LEDs, which are then each controlled by a power controller.

[0021] According to the invention, the lighting unit 21 further comprises a light source control device 21.30, which is connected to the one or more power controllers 21.20. The light source control device 21.30 can be a microcontroller. The light source control device 21.30 is configured to query parameters and operating data from the power controllers 21.20. The parameters and operating data can be, for example, the temperature of the LEDs 21.11, the temperature of the power controllers 21.20, or the light output at the first electrical power value.

[0022] Each of the power controllers 21.20 has an input which is identical to the input 21.4 of the lighting unit 21 of the Fig. 2 and can be connected to the start line 23. An output of each of the power regulators 21.20 is connected via a line 21.50, which corresponds to the line 21.5 of the Fig. 2 corresponds to an input of one of the groups 21.10 of the light source 21.1, in particular to the LEDs 21.11 of the corresponding group 21.10.

[0023] In the Fig. 5 An embodiment of a lighting device is shown. The lighting device 20 of the Fig. 5 has a plurality of lighting units 21, each lighting unit 21 having a light source 21.1 and at least one power controller 21.2. The lighting unit 21 can be designed according to one of the embodiments of the Fig. 2 or Fig. 3 be executed.

[0024] The lighting device 20 further comprises a main control device 22 which is connected to a start line 23 which is connected to each of the power regulators 21.2, wherein the main control device 22 is configured to generate the start signal and supply it to the start line 23.

[0025] According to one example of the lighting device 20, the lighting units 21 can be integrated into an Ethernet network connected to the main control device 22, wherein, for example, exactly one Ethernet line can be connected to each lighting unit 21, in particular to the light source control device 21.30 of the lighting unit 21. The light source control device 21.30 can then in turn be connected to the power controllers 21.20 via an RS485 bus system, via which the parameters and operating data are transmitted and forwarded to the Ethernet network.

[0026] The start signal can be triggered manually by an operator or automatically. In the latter case, the start signal can be triggered, for example, by a light barrier or an electrical contact on the simulation setup for motor vehicle accidents. It can be provided that the start signal cannot be triggered if at least one power controller delivers parameters or operating data of the respective associated light source 21.10 via the RS485 bus system that do not meet certain requirements or lie outside predetermined ranges, thus indicating a lack of operational readiness or insufficient performance of the associated light source. Accordingly, the start signal is only triggered if all light sources or all LED groups report sufficient operational readiness based on the transmitted parameters or operating data.

[0027] The start signal is applied simultaneously to the lighting units 21 to initiate the increase in electrical power from the first value to the second value. The start signal can, for example, be a 24V square-wave signal, the duration of which must be sufficient to be recognized by the electrical circuitry of the power controllers 21.2 or 21.20. In any case, the duration is shorter than the specified period during which the light source is supplied with the second value of electrical power.

[0028] The starting line 23 can be a single-wire or a two-wire line. According to an example of a two-wire line, three ground lines and two signal lines are required. The two signal lines each transmit the wanted signal with opposite polarity. This configuration can suppress common-mode interference. As shown in Fig. 3 As shown, the starting line 23 has a corresponding number of branches to the power regulators 21.20. The inputs 21.40 of the power regulators 21.20 are designed to be connected to a starting line as described above.

[0029] The light source control device 21.30 can also have an input connected to the start line 23. The start signal can, for example, trigger an event counter in the light source control device 21.30.

[0030] According to one example of the lighting device 20, each power controller 21.2 is configured to maintain the supplied electrical power at the second value for a predetermined period of time and to reduce it back to the first value after the predetermined period of time has elapsed. The predetermined period of time is selected such that a crash test can be conducted and the images can be captured with the high-speed cameras during the crash test. It can be in a range between 5 s and 30 s, in particular between 10 s and 20 s, preferably approximately 15 s.

[0031] A simulation arrangement for motor vehicle accidents can comprise a lighting device as described above. The simulation arrangement can, in particular, be connected to the main control device of the lighting device, wherein a signal triggering the start signal is generated by the simulation arrangement by means of a light barrier or an electrical contact and transmitted to the main control device. It can also be provided that the lighting device, in particular the main control device, is synchronized with one or more of the high-speed cameras.

[0032] To operate a lighting device for a simulation arrangement for motor vehicle accidents as described above, the electrical power supplied to the light source is increased from a first value to a second value, wherein the first value is different from zero and the second value is greater than the first value.

[0033] For example, the electrical power can be maintained at the second value during a predetermined period of time and the lighting units can be monitored before and after the predetermined period of time and parameters and operating data of the light source and a power controller controlling the light source can be collected.

[0034] Furthermore, a start signal can be generated and simultaneously applied to the lighting units to initiate the increase in electrical power from the first value to the second value. The start signal can be triggered by a light barrier or an electrical contact on the motor vehicle accident simulation setup.

[0035] Further examples can be formed by combining with features and embodiments described above in connection with the lighting device.

[0036] In the Fig. 6A current-time diagram is shown which illustrates the time dependence of the current I supplied to the light source. The current-time diagram has three phases I - III. In the first phase I, the current supplied to the light sources is at a value of 30% of the maximum value of 100% of the current. The second phase II is initiated by the start signal supplied to the lighting units 21.2 or 21.20. The increase in the electrical current from 30% to 100% can, for example, occur in a time period ranging from 1 µs to 20 µs. During the second phase II, which in this example covers a period of 15 s, the current supplied to the lighting units is increased to the maximum value of 100% and the crash test is carried out. In the third phase III, after the crash test has ended or after the high-speed camera has finished recording, the current I supplied to the lighting units is reduced back to the initial value of, for example, 30%.

[0037] Although specific embodiments have been shown and described in this specification, it will be appreciated by those skilled in the art that the specific embodiments shown and described may be substituted for a variety of alternative and / or equivalent implementations without departing from the scope of the present claims. This disclosure is limited only by the claims.

Claims

1. Illumination unit (21), comprising - a light source (21.1; 21.10); - a power controller (21.2; 21.20) configured to control the supply of electrical power to the light source (21.1) such that, upon receipt of a start signal, the supplied electrical power is increased from a first value to a second value, the first value being different from zero and the second value being greater than the first value; and - an input (21.4) for supplying the start signal; characterised by a light source control device (21.30) which is connected to the power controller (21.2; 21.20) and is configured to request parameters and operating data from the power controller (21.2; 21.20).

2. Illumination unit (21) according to claim 1, in which the light source (21.1) comprises a plurality of groups of LEDs (21.11) and a corresponding plurality of power controllers (21.20) and each group is connected to a power controller (21.20).

3. Illumination unit (21) according to claim 2, wherein the light source control device (21.30) is connected to the plurality of power controllers (21.20) and is configured to request parameters and operating data from the power controllers (21.20).

4. Illumination unit (21) according to one of the preceding claims, in which the parameters and operating data comprise one or more of the following data: the temperature of the LEDs (21.11), the temperature of the power controllers (21.2; 21.20), and the light output at the first value of the electrical power.

5. Illumination unit (21) according to claim 3 or 4, wherein the light source control device (21.30) is connected to the power controllers (21.2; 21.20) via an RS485 bus system.

6. Illumination unit (21) according to one of the preceding claims, in which the or each power controller (21.2; 21.20) is configured to maintain the supplied electrical power at the second value for a predetermined period of time and to lower it back to the first value after the predetermined period of time has elapsed.

7. Illumination unit (21) according to one of the preceding claims, in which the first value of the electrical power is in a range between 20% and 40% of the second value of the electrical power .

8. Use of illumination units in a lighting device (20) for a simulation arrangement for motor vehicle accidents, comprising: - a plurality of lighting units (21) included in the lighting device (20) according to one of the preceding claims; and - a main controller (22) connected to a start line (23) connected to each of the power controllers (21.2), wherein the main controller (22) is configured to generate and supply the start signal to the start line (23).

9. Use according to claim 8, wherein the main control device (22) is connected to the lighting units (21) by an Ethernet.