Display device, system and method for calibrating an optical sensor installed in a motor vehicle

Abstract

A display device (30) for calibrating an optical sensor (4) of a driver assistance system installed in a motor vehicle (2) comprises a monitor (32) that is provided and configured to display at least one calibration pattern for calibrating the optical sensor (4) on a front side of the display device (30), and at least one target pattern (40, 42) formed on a rear side of the display device (30).

Description

[0001] R.417306

[0002] - 1 -

[0003] Description

[0004] title

[0005] Display device, system and method for calibrating an optical sensor installed in a motor vehicle

[0006] The invention relates to a display device, a system and a method for calibrating an optical sensor installed in a motor vehicle.

[0007] State of the art

[0008] To calibrate optical sensors of driver assistance systems installed in motor vehicles, calibration targets with calibration patterns are positioned in predetermined positions in front of the sensor to be calibrated.

[0009] To enable accurate calibration of the optical sensors, the calibration patterns must be positioned as precisely as possible at the specified positions.

[0010] Different optical sensors generally require different calibration patterns, and the calibration patterns must be positioned at different locations in front of the vehicle depending on the sensor being calibrated.

[0011] It is an object of the invention to provide a display device, a system and a method for calibrating optical sensors installed in a motor vehicle, which facilitate and simplify the calibration of optical sensors of driver assistance systems installed in motor vehicles.

[0012]

[0013] R.417306

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[0015] A display device according to the invention for calibrating an optical sensor of a driver assistance system installed in motor vehicles comprises a monitor designed and configured to display at least one calibration pattern for calibrating the optical sensor on a front side of the display device. A display device according to the invention further comprises at least one target pattern formed on a rear side of the display device.

[0016] The invention also includes a system for calibrating an optical sensor of a driver assistance system, wherein the system comprises a display device according to the invention and at least one holding device which makes it possible to position the display device in front of the optical sensor of the motor vehicle.

[0017] The monitor of a display device according to the invention makes it possible to select or calculate a calibration pattern, depending on the type of sensor to be calibrated and depending on the position and orientation of the sensor relative to the display device, and to display it on the monitor of the display device. Using the calibration pattern displayed individually on the monitor of the display device for each calibration process, the sensor installed in the motor vehicle can be calibrated reliably and with high accuracy.

[0018] A display device according to the invention can therefore be used to calibrate a large number of different sensors.

[0019] If necessary, several different calibration patterns can be displayed on the monitor during the calibration process.

[0020] The monitor can be a cost-effective black and white monitor for displaying monochrome calibration patterns. Alternatively, the monitor can be a color monitor capable of displaying colored calibration patterns.

[0021] The monitor can be, for example, an LCD monitor, an LED monitor, or electronic paper. R.417306

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[0023] The target patterns formed on the back of the display device make it possible to determine the position and orientation of the display device, and thus also the position and orientation of the calibration pattern displayed on the monitor of the display device, with high accuracy and to take this into account when calibrating the sensor installed in the motor vehicle.

[0024] The sensor installed in the motor vehicle can therefore be calibrated with high accuracy without having to position the display device in a precisely predetermined position in front of the motor vehicle.

[0025] In one embodiment, a system according to the invention for calibrating an optical sensor comprises at least one scanning device configured to optically detect the body of the motor vehicle and the at least one target pattern formed on a rear side of the display device in order to determine the position and orientation of the display device in relation to the motor vehicle.

[0026] With the help of at least one scanning device, the current position and orientation of the display device relative to the motor vehicle can be determined easily and with very high accuracy.

[0027] In one embodiment, several target patterns are formed on the back of the display device. The target patterns can be integral to the back of the display device. Alternatively, the target patterns can be printed, painted, or glued onto the back of the display device.

[0028] A protective layer, such as a protective coating, may be applied to the target patterns to protect them from scratches and other signs of wear.

[0029] In one embodiment, the target patterns comprise flat target patterns and raised target patterns, the latter having a three-dimensional structure.

[0030] Using multiple target patterns, including in particular flat and raised target patterns, the position and orientation of the R.417306 can be determined.

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[0032] The display device in front of the motor vehicle allows for particularly reliable and accurate determination.

[0033] In one embodiment, at least one camera is provided on the front of the display device, enabling the capture of images of the vehicle, particularly images containing the sensor to be calibrated. With the aid of such a camera, the position of the sensor to be calibrated relative to the display device can be determined with exceptional accuracy. This allows the sensor to be calibrated with particularly high precision.

[0034] At least one camera can be a mono camera, a stereo camera, a black and white camera, or a color camera.

[0035] In one embodiment, at least two cameras are provided on the front of the display device. The at least two cameras on the front of the display device can be oriented differently. In particular, they can be oriented such that the display device can be operated in different spatial orientations, especially in a horizontal and a vertical orientation.

[0036] In one embodiment, the at least two cameras comprise at least one first camera arranged at a first edge of the display device and intended for horizontal operation of the display device, and at least one second camera arranged at a second edge of the display device and intended for vertical operation of the display device. The second edge may extend transversely, in particular at a right angle, to the first edge.

[0037] In one embodiment, the display device has lateral coupling areas designed and configured for mechanical connection to mounting devices. This allows the display device to be easily and securely connected to mounting devices in order to position the display device in front of the vehicle.

[0038] In one embodiment, the display device has first lateral coupling areas that allow the display device to be mounted in a horizontal orientation. R.417306

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[0040] to connect to the mounting brackets, and second lateral coupling areas that allow the display unit to be connected to the mounting brackets in a vertical orientation. In this way, the display unit can be easily attached to the mounting bracket in two different orientations and positioned in front of the vehicle.

[0041] The lateral coupling areas can be designed, in particular, as recesses in the side surfaces of the display device.

[0042] In one embodiment, the display device has a display element that enables information for the correct positioning and alignment of the display device in front of the sensor to be calibrated to be shown. The display element can, in particular, be located on the rear of the display device.

[0043] The display device can be designed, for example, as an LED display device, an LCD display device, or as electronic paper.

[0044] The display device can be configured, in particular, to show information that enables a user to position the display device precisely in front of the sensor to be calibrated. The display device can also be configured to indicate to the user whether the display device is positioned with sufficient accuracy in front of the sensor to be calibrated in order to perform the sensor calibration.

[0045] In one embodiment, both the display device and the at least one scanning device have a transmitting and receiving device that enables the display device and the at least one scanning device to communicate with each other wirelessly or via a wired connection.

[0046] Wireless communication can take place, for example, via a WLAN or Bluetooth connection.

[0047] The invention also includes methods for calibrating an optical sensor of a driver assistance system using a system according to the invention. One method according to the invention comprises calibrating the display device using R.417306.

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[0049] to position at least one holding device in front of the optical sensor of the motor vehicle; to detect the position of the optical sensor with at least one camera on the display device; to position at least one scanning device in front of the motor vehicle in such a way that the scanning device is able to optically detect at least a partial area of ​​the motor vehicle and the at least one target pattern formed on a rear side of the display device; to determine the position and orientation of the display device in front of the optical sensor based on the information supplied by the scanning device and the camera; to determine a calibration pattern for calibrating the optical sensor based on the position and orientation of the display device in front of the optical sensor thus determined; and to display the calibration pattern thus determined on the monitor of the display device.

[0050] The procedure also includes calibrating the sensor to be calibrated using the calibration pattern displayed on the monitor of the display device.

[0051] In one embodiment, the method comprises the display device and the at least one scanning device communicating with each other wirelessly or via a wired connection.

[0052] In one embodiment, the method comprises displaying various calibration patterns on the monitor in succession.

[0053] In one embodiment, the method additionally includes displaying information on a display device of the display unit regarding the correct positioning and alignment of the display unit in front of the sensor.

[0054] An embodiment of the invention is described below with reference to the accompanying figures.

[0055] Brief description of the figures R.417306

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[0057] Figure 1A shows a first perspective view of a system according to the invention for calibrating an optical sensor installed in a motor vehicle.

[0058] Figure 1B shows a second perspective view of the system shown in Figure 1A.

[0059] Figure 2 shows the front of a display device according to the invention.

[0060] Figure 3 shows a top view of the back of the display device according to the invention.

[0061] Figure 4 shows a perspective view of the back of the display device according to the invention.

[0062]

[0063] Figures 1A and 1B show perspective views of a system 10 according to the invention for calibrating an optical sensor 4 installed in a motor vehicle 2, which is positioned in front of a motor vehicle 2.

[0064] The system 10 comprises a display device 30, which is positioned in front of the optical sensor 4 to be calibrated, in particular in front of the windshield 6 of the motor vehicle 2, by means of a holding device 14.

[0065] The holding device 14 comprises two vertical supports 16, which are fixed to the front wheels 8 of the motor vehicle 2 by means of clamping holders 18, and a horizontal support 20. The horizontal support 20 extends horizontally in front of the windshield 6 of the motor vehicle 2 between the two vertical supports 16 and carries the display device 30.

[0066] The horizontal support 20 comprises, in particular, two horizontal support elements 20a, 20b, each extending between one of the two vertical supports 16 and the display device 30. R.417306

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[0068] The system 10 also includes two scanning devices 24, which are arranged on tripods 22 and positioned in front of the motor vehicle 2.

[0069] Each of the two scanning devices 24 has at least one camera that makes it possible to take pictures of the motor vehicle 2 and the display device 30.

[0070] The cameras installed in the 24 scanning devices can be mono cameras, stereo cameras, black and white cameras or color cameras.

[0071] The scanning devices 24 are each equipped with a transmitting and receiving device 26, which makes it possible to communicate wirelessly or via a wired connection with the respective scanning device 24.

[0072] Figure 2 shows the front of a display device 30 according to the invention. The front of the display device 30 faces the sensor 4 to be calibrated during operation, as shown in Figure 1B.

[0073] The display device 30 comprises a monitor 32, which is designed and configured to display at least one calibration pattern on the front of the display device 30, the pattern being designed and suitable for calibrating the optical sensor 4. The calibration pattern is not shown in the figures.

[0074] Because at least one calibration pattern is displayed on the monitor 32, the calibration pattern is variable. Therefore, the at least one calibration pattern can be adapted to the sensor 6 to be calibrated, to the position of the sensor 6 to be calibrated in the vehicle 2, and to the current position of the display device 30 in front of the vehicle 2.

[0075] The monitor 32 is surrounded by a frame 38. The frame 38 can be designed, in particular, as a shock-absorbing frame 38 to protect the monitor 32 from mechanical damage.

[0076] Frame 38 incorporates four handles 39 to facilitate the handling of the display unit 30. R.417306

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[0078] In the embodiment shown in the figures, the display device 30 and the monitor 32 are essentially rectangular. The display device 30 and the monitor 32 could also have a different geometry, for example, square.

[0079] A first camera 34 is provided on the front of the display device 30 on one of its two long sides. A second camera 36 is provided on the front of the display device 30 on one of its two short sides.

[0080] The two cameras 34, 36 are designed and configured to capture images of the motor vehicle 2, in particular the front and the windshield 6 of the motor vehicle 2 (see Figures 1A and 1B). By evaluating the images captured by the cameras 34, 36, the position of the sensor 4 to be calibrated in relation to the display device 30 can be determined.

[0081] The first camera 34 is intended for operation in a horizontal orientation of the display device 30, as shown in Figures 1A, 1B and 2.

[0082] The second camera 36 is intended for operation in a vertical orientation of the display device 30, in which the display device 30 is rotated by 90° about an axis extending at a right angle to the plane of the monitor 32.

[0083] The cameras 34, 36 present in the display unit 30 can be mono cameras, stereo cameras, black and white cameras or color cameras.

[0084] In an embodiment not shown in the figures, the display device 30 can also be equipped with only a single camera 34, 36. The display device 30 can be equipped with a single camera 34, 36, in particular, if the display device 30 is to be operated only in the horizontal position or only in the vertical position.

[0085] Figure 3 shows a top view of the rear of the display unit 30, and Figure 4 shows a perspective view of the rear of the display unit 30.R.417306

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[0087] In operation, the back of the display device 30 is turned away from the sensor 4 to be calibrated and towards the two scanning devices 24, as shown in Figure 1 A.

[0088] On the back of the display device 30 are several target patterns 40, 42, which make it possible to determine the position and orientation of the display device 30 in space, in particular in relation to the motor vehicle 2, from the images of the back of the display device 30 taken by the cameras of the scanning devices 24.

[0089] The target patterns 40, 42 can be integrally formed with the back of the display device 30. The target patterns 40, 42 can also be printed, painted, or glued onto the back of the display device 30.

[0090] A protective layer, in particular a protective coating, may be applied to the target patterns 40, 42 to protect the target patterns 40, 42 from scratches and other signs of wear.

[0091] Some of the target patterns 40, 42 are formed as flat target patterns 40 and some of the target patterns 40, 42 are formed as raised target patterns 42.

[0092] In particular, four flat target patterns 40 are formed on the back of the display device 30, which are arranged in the four corners of the rectangular back of the display device 30 within the protective frame 38.

[0093] In the embodiment shown in Figures 3 and 4, the flat target patterns 40 are each rectangular, in particular square, with an optically detectable black and white pattern.

[0094] In addition, eight raised target patterns 42 are formed on the back of the display device 30 shown in the figures.

[0095] In the embodiment shown in Figures 3 and 4, the raised target patterns 42 each have a circular cross-section. R.417306

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[0097] The raised target patterns 42 each have in particular a base area 44 which tapers with increasing distance from the rear of the display device 30, and a flat area 46 formed thereon on which an optically detectable pattern is formed.

[0098] In the embodiment shown in the figures, the raised target patterns 42 are arranged in two rows, each row comprising four raised target patterns 42. The two rows extend horizontally between two flat target patterns 40, parallel to the longitudinal sides of the display device 30.

[0099] The design and arrangement of the target patterns 40, 42 shown in the figures is only exemplary. In further embodiments of the display devices 30 according to the invention, which are not explicitly shown in the figures, the target patterns 40, 42 can also be designed and arranged in other configurations.

[0100] On the back of the display unit 30, there is also a battery compartment 48 for receiving (not shown in the figures) batteries intended to supply the display unit 30 with electrical energy, a service compartment 50, an on / off switch 52 and a display device 54.

[0101] The service compartment 50 has a transmitting and receiving device 55 which enables the display device 30 to communicate wirelessly or via a wired connection.

[0102] The transmitting and receiving device 55 can enable the display device 30 in particular to communicate wirelessly and / or via wired connections with the scanning devices 24 which are positioned in front of the motor vehicle 2.

[0103] Wireless communication can take place, for example, via a WLAN or Bluetooth connection.

[0104] The display device 54 can be configured as an LED display device 54, an LCD display device 54, or as electronic paper 54, which esR.417306

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[0106] The display unit 30 enables the user of the display unit 30 to output information and / or instructions.

[0107] The display device 54 may in particular be designed to output information and / or instructions that enable a user to position the display device 30 in a position and orientation suitable for calibrating the sensor 4 in front of the motor vehicle 2.

[0108] In the perspective view of the display device 30 shown in Figure 4, it can be seen that coupling areas 56, 58 are formed in the side surfaces of the display device 30, which extend between the front shown in Figure 2 and the rear shown in Figure 3 of the display device 30, which make it possible to couple the display device 30 with the support elements 20a, 20b in order to position the display device 30 in front of the motor vehicle 2 with the help of the support elements 20a, 20b, as shown in Figures 1 A and 1 B.

[0109] The coupling areas 56, 58 are specifically designed as receptacles for receiving the support elements 20a, 20b, which may be designed, for example, as cylindrical tripod tubes.

[0110] The display device 30 has in particular first coupling areas 56 which are formed in the shorter transverse sides 31 of the display device 30 and which make it possible to connect the display device 30 in a horizontal orientation with the support elements 20a, 20b as shown in Figures 1 A and 1 B.

[0111] The display device 30 also has second coupling areas 58 formed in the longer longitudinal sides 33 of the display device 30. The second coupling areas 58 make it possible to connect the display device 30 in a vertical orientation with the support elements 20a, 20b, in which the display device 30 is rotated 90° relative to the horizontal orientation about an axis that extends at a right angle to the plane of the monitor 32 or to the plane of the rear of the display device 30. R.417306

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[0113] Thus, depending on the specific requirements of the sensor 4 to be calibrated, the display device 30 can be arranged either in a horizontal or in a vertical orientation in front of the sensor 4.

[0114] In order to calibrate an optical sensor 4, in particular an optical sensor 4 of a driver assistance system installed in a motor vehicle 2, using a system 10 according to the invention, a display device 30 according to the invention is positioned in the field of view of the optical sensor 4 using the at least one holding device 14, as shown in Figures 1 A and 1 B.

[0115] The method comprises positioning at least one scanning device 24, in particular two scanning devices 24, in front of the motor vehicle 2 such that the camera(s) of the scanning device(s) 26 is / are able to optically detect at least a partial area of ​​the motor vehicle 2 and the target patterns 42, 44 which are formed on the back of the display device 30.

[0116] Using an image evaluation device not explicitly shown in the figures, which may be formed in the display device 30 or in one of the scanning devices 24, the images taken by the camera(s) of the scanning device(s) 26 are evaluated in order to determine the position and orientation of the display device 30 in relation to the motor vehicle 2.

[0117] The position and orientation of the display device 30 in front of the motor vehicle 2 thus determined can be compared with a predetermined position or orientation.

[0118] If necessary, instructions can be issued to the user on the display device 54, which is formed on the rear of the display unit 30, to change the position and / or orientation of the display unit 30 in front of the motor vehicle 2 until the position and / or orientation of the display unit 30 in front of the motor vehicle 2 corresponds to the specifications, e.g. of the manufacturer, for calibrating the sensor 4.

[0119] With at least one of the cameras 34, 36 provided on the front of the display device 30, at least one image of the front is then taken, R.417306

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[0121] In particular, the windshield 6 of the motor vehicle 2 is recorded, and the sensor 4 to be calibrated is identified in the at least one recorded image. Based on the image recorded by the at least one camera 34, 36, the position and orientation of the sensor 4 to be calibrated in relation to the display device 30 are determined.

[0122] Depending on the type of sensor 4 to be calibrated, as well as its position and orientation relative to the display device 30, which have been determined as described above, a calibration pattern is then selected or calculated and displayed on the monitor 32 of the display device 30.

[0123] Using the calibration pattern displayed on the monitor 32 of the display unit 30, the sensor 4 installed in the motor vehicle 2 can then be calibrated reliably and with high accuracy.

Claims

R.417306 - 15 - Patent claims 1. Display device (30) for calibrating an optical sensor (4) of a driver assistance system installed in a motor vehicle (2), wherein the display device (30) comprises: a monitor (32) designed and configured to display at least one calibration pattern for calibrating the optical sensor (4) on a front side of the display device (30); and at least one target pattern (40, 42) formed on a rear side of the display device (30).

2. Display device (30) according to claim 1, wherein several target patterns (40, 42) are formed on the back of the display device (30).

3. Display device (30) according to claim 2, wherein the target patterns (40, 42) comprise flat target patterns (40) and raised target patterns (42).

4. Display device (30) according to one of the preceding claims, wherein at least one camera (34, 36) is provided on the front of the display device (30).

5. Display device (30) according to claim 4, wherein at least two cameras (34, 36) are provided on the front of the display device (30), wherein the at least two cameras (34, 36) comprise at least one first camera (34) for horizontal operation of the display device (30), which is arranged at a first edge of the display device (30); and R.417306 - 16 - wherein the at least two cameras (34, 36) include at least a second camera (36) for vertical operation of the display device (30), which is arranged on a second edge of the display device (30); wherein the second edge (31) extends transversely, in particular at a right angle, to the first edge (33).

6. Display device (30) according to one of the preceding claims, wherein the display device (30) has lateral coupling areas (56, 58) which are provided and designed for mechanical connection with holding devices (14); wherein the display device (30) in particular has first lateral coupling areas (56) which make it possible to connect the display device (30) in a horizontal orientation with the holding devices (14); and wherein the display device (30) in particular has second lateral coupling areas (58) which make it possible to connect the display device (30) in a vertical orientation with the holding devices (14).

7. Display device (30) according to one of the preceding claims, wherein the display device (30) comprises a transmitting and receiving device (55) which enables wired or wireless communication.

8. Display device (30) according to one of the preceding claims, wherein the display device (30) has a display device (54) which makes it possible to display information, in particular information on the correct positioning and orientation of the display device (30) in front of the sensor (4); wherein the display device (54) is formed in particular on the back of the display device (30).

9. System (10) for calibrating an optical sensor (4) of a driver assistance system, wherein the system (10) comprises: a display device (30) according to one of claims 1 to 8, R.417306 - 17 - at least one holding device (14) which makes it possible to position the display device (30) in front of the optical sensor (4) of the motor vehicle (2).

10. System (10) according to claim 9, wherein the system (10) further comprises at least one scanning device (24) configured to optically detect the body of the motor vehicle (2) and the at least one target pattern (40, 42) formed on a rear side of the display device (30) in order to determine the position and orientation of the display device (30) in relation to the motor vehicle (2).

11. System (10) according to claim 9, wherein the system (10) comprises two scanning devices (24).

12. System (10) according to any one of claims 9 to 11, wherein at least one scanning device (24) has a transmitting and receiving device (26) which enables the scanning device (24) to communicate wirelessly.

13. Method for calibrating an optical sensor (4) of a driver assistance system with a system (10) according to one of claims 9 to 12, wherein the method comprises: to position the display device (30) in front of the optical sensor (4) of the motor vehicle (2) using at least one holding device (14); to detect the position of the optical sensor (4) with at least one camera (34, 36) on the display device; to position at least one scanning device (24) in front of the motor vehicle (2) such that the scanning device (24) is able to optically detect at least a partial area of ​​the motor vehicle (2) and the at least one target pattern (40, 42) formed on a rear side of the display device (30); R.417306 - 18 - to determine the position and orientation of the display device (30) in front of the optical sensor (4) based on the information supplied by the scanning device (24) and the camera (34, 36); to determine a calibration pattern for calibrating the optical sensor (4) based on the position and orientation of the display device (30) in front of the optical sensor (4) thus determined; and to display the calibration pattern determined in this way on the monitor (32) of the display device (30).

14. Method according to claim 13, wherein the method further comprises displaying information on a display device (54) for the correct positioning and alignment of the display device (30) in front of the sensor (4).

Images