Method for teleoperated control of a ground-based passenger motor vehicle

Abstract

The invention relates to a method for teleoperated control of a ground-based passenger motor vehicle (1), wherein an operator controls the passenger motor vehicle (1) using a control unit (2) arranged spatially separately from the passenger motor vehicle (1). Image data (BD1, BD2) are reliably transmitted between the passenger motor vehicle (1) and the control unit (2) by virtue of the passenger motor vehicle (1) having at least two camera devices (30, 40) which each have a camera (31, 41) and an integration unit (32, 42), wherein: the camera (31, 41) is used to provide image data (BD1, BD2) based on a capture of camera images; the integration unit (32, 42) is used to output extended image data (eBD1, eBD2) based on an integration of an encoded information block which comprises a source reference (Q) specific to the particular camera (31, 41) and a timestamp (Z) specific to the capture; the extended image data (eBD1, eBD2) are transmitted from the passenger motor vehicle (1) to the control unit (2); the image data (BD1, BD2) and / or the extended image data (eBD1, eBD2) are displayed to the operator, for control of the passenger motor vehicle (1), by means of a display device (6) of the control unit (2); and the extended image data (eBD1, eBD2) are validated on the basis of the integrated information block by means of a validation unit (60) coupled to the display device (6).

Description

[0001] Method for teleoperated control of a ground-based passenger vehicle

[0002] The invention relates to a method for the teleoperated control of a ground-based passenger vehicle having the features of the preamble of patent claim 1.

[0003] In such a method for the teleoperated control of a ground-based passenger vehicle, an operator controls the passenger vehicle using a control unit located spatially separate from the passenger vehicle. During teleoperated control, the operator is physically decoupled from the vehicle. The driving tasks to be performed are performed remotely. The passenger vehicle has one or more cameras, the data from which is transmitted to the control unit and presented to the operator via a display device on the control unit for controlling the passenger vehicle. The operator can thus detect obstacles, road conditions, or traffic signs and control the passenger vehicle accordingly. The passenger vehicle is also referred to as a vehicle or car in this document.

[0004] However, errors can occur during data transmission. For example, images from a camera may be displayed on the wrong screen of the display device, causing the operator to assign the wrong position to the objects shown in the images. Furthermore, a still image could be displayed. Errors involving the display of cyclic images are also conceivable. An image displayed with a significant delay is also considered an error. Such incorrect information can lead to misinterpretation of the actual situation and thus to inappropriate driving maneuvers on the part of the operator.

[0005] The invention is therefore based on the object of designing and / or developing the method for remotely controlling a ground-based passenger vehicle in such a way that the disadvantages of the prior art are avoided or at least reduced. In particular, a secure transmission of image data between the passenger vehicle and the control unit is to be achieved.

[0006] This object underlying the invention is now initially achieved by a method for the teleoperated control of a ground-based passenger vehicle with the features of patent claim 1. One aspect of the invention essentially lies in the fact that the passenger vehicle has at least two camera devices, each with a camera and an integration unit, wherein image data is provided by means of the camera based on a recording of camera images, wherein extended image data is output by means of the integration unit based on an integration of a coded information block, which includes a source information specific to the respective camera and a time stamp specific to the recording, wherein the extended image data is transmitted from the passenger vehicle to the control unit,wherein the image data and / or the extended image data are displayed by means of a display device of the control unit for the operator to control the passenger vehicle, wherein the extended image data are validated on the basis of the integrated information block by means of a validation unit coupled to the display device.

[0007] Advantageously, the entire transmission path can be validated by using the coded information block, which includes the source information and the timestamp, which is imprinted on the image data in the passenger vehicle and read out in the control unit. The extended image data can be validated, for example, using the information block to determine whether the correct image source is being displayed on the corresponding screen. Furthermore, the obscuration of a relevant image, for example, by another video image or incorrect image composition within the transmission, can be detected. Furthermore, a freeze frame or the transmission of a cyclical or significantly delayed image can be detected.By embedding the information block in the image data provided by the camera, a security channel is advantageously created between the recording camera and the display device. The source information as part of the coded information block and thus as part of certain extended image data is suitable for specifying the camera providing the image data. The source information can also be referred to as identification information or ID or source ID. The source information is preferably generated based on a hardware ID of the camera. The timestamp indicates the time or period of time at which the camera images were recorded by the camera providing the image data. In particular, a control unit is provided which is configured to control the integration unit and the camera. The control unit is in particular part of the camera device.The control unit includes, for example, electronics such as a microprocessor or a CPLD (Complex Programmable Logic Device). The camera is preferably designed as a video camera. The use of daylight cameras, thermal imaging cameras, and / or infrared cameras is also conceivable. In particular, different camera systems can also include different camera types.

[0008] Preferably, the enhanced image data is transmitted wirelessly via a vehicle antenna of the passenger vehicle to a transmission antenna, and from the transmission antenna to the control unit. The wireless transmission between the vehicle antenna and the transmission antenna allows the passenger vehicle to move freely.

[0009] According to an advantageous embodiment of the method, the transmission antenna is designed as a mobile radio antenna. Wireless transmission between the vehicle antenna and the transmission antenna thus takes place via a mobile radio network. To enable real-time transmission of the image data, a 5G mobile radio network is preferably used.

[0010] Further preferably, the enhanced image data is transmitted from the transmission antenna to a data input of the control unit via a cable. This cable transmission preferably takes place via the internet, in particular via fiber optic cable.

[0011] According to a further embodiment of the method, the enhanced image data is transmitted wirelessly from the transmission antenna to a control unit antenna of the control unit. The control unit antenna is then part of the data input of the control unit. The data input then has the control unit antenna to enable wireless reception of image data. Here, too, the mobile network, particularly according to the 5G standard, is preferably used.

[0012] The representation of the vehicle's surroundings for the operator by means of the image data is particularly little disturbed if the information block is encoded in an area of ​​the extended image data that is not visible to the operator, in particular in a black level area of ​​the extended image data.

[0013] Preferably, a hash value calculated from the image data is additionally encoded into the coded information block by means of the integration unit. The hash value is calculated using a hash function and represents a type of security code. The hash value can be read, for example, in a screen monitoring device and / or the validation unit using the known hash function also present here. Using the hash values, validation can be carried out with less error-proneness and less effort. Further preferably, a QR code is generated by means of the integration unit in such a way that the QR code contains the source information and the timestamp in coded form. Advantageously, the use of a QR code as an information block allows a certain degree of error tolerance and thus a configurable permissible coverage rate.

[0014] According to a preferred embodiment of the method, the QR code is encoded in an area of ​​the enhanced image data that is invisible to the operator, in particular in a black level area of ​​the enhanced image data. The least significant bit (LSB) is preferably used. Thus, the QR code is preferably encoded in the image in a way that is invisible to the operator and thus cannot disturb the operator. The position of the QR code is preferably distributed randomly across a central image area, in particular to reduce losses in image dynamics.

[0015] According to a particularly preferred embodiment of the method, a hash value calculated from the image data is additionally encoded into the QR code by means of the integration unit. The calculated hash values ​​integrated into the QR code can advantageously be used for a subsequent image verification, for example, with regard to still images or cyclic images. Such an image verification can be performed, for example, in the screen monitoring device and / or the validation unit.

[0016] Preferably, each camera device has a camera monitoring device that includes the integration unit. The image data and / or the extended image data are transmitted from the camera to the camera monitoring device and from the camera monitoring device to the vehicle antenna via a respective image transmission interface, in particular via a camera link. The camera monitoring device can also be referred to as a camera watchdog.

[0017] According to a further embodiment, the validation unit and the respective integration unit are time-synchronized using a common time base. The time synchronization of the integration unit and the validation unit makes it possible to reliably calculate latency times during the transmission of the image data from the transmitted timestamps, which are part of the information blocks.

[0018] Preferably, the display device has at least two screens. Each screen is coupled to the data input via a screen monitoring device. The enhanced image data is transmitted from the data input to the screen monitoring device and from the screen monitoring device to the screens via a respective digital image transmission interface, in particular via a digital visual interface.

[0019] Further preferably, an image check is carried out with respect to a still image supplied by the respective camera or with respect to cyclic images in the extended image data by means of a comparison of hash values ​​transmitted by the extended image data and / or as a function of a fast Fourier transformation by means of the screen monitoring device.

[0020] The validation unit is preferably connected to the screen monitoring device via an interface, for example, an Ethernet networking interface. The source information and the timestamp are extracted from the enhanced image data using the screen monitoring device, and the extracted source information and timestamp are transmitted via the interface to a control device of the control unit that includes the validation unit. This ensures the correct correlation between display and recording, and determines the time delay, i.e., the latency of the image data.

[0021] According to a further embodiment of the method, an action is initiated or executed by means of the control device depending on the validation carried out by the validation unit.

[0022] Advantageously, an emergency braking of the passenger vehicle is carried out if the validation indicates a display of an image from a wrong camera by the corresponding screen, or if the validation indicates an occlusion of the corresponding camera, or if the validation indicates a display of a still image by the corresponding screen, or if the validation indicates a display of a cyclic image by the corresponding screen, or if the validation indicates a display of a strongly delayed image by the corresponding screen.

[0023] For example, if validation shows that a particular monitor is supposed to display images from camera A but is actually displaying images from camera B, the action to be performed could be an emergency braking of the passenger vehicle. A severely delayed image is one with a delay greater than a predetermined threshold. A cyclic image can occur, for example, if a memory is mistakenly repeatedly read instead of displaying current video images.

[0024] Advantageously, an overlay or a black image is displayed on the corresponding screen if the validation indicates that the corresponding camera is obscured. This ensures that the operator does not perform driving maneuvers based on incorrect information. Typically, at least one additional screen provides sufficient information to safely control the vehicle, for example, to safely perform emergency braking.

[0025] Further preferred is to mark transmitted image data as a freeze frame if the validation indicates a freeze frame, a cyclic frame, or a significantly delayed frame. This also prevents the operator from performing maneuvers based on incorrect information.

[0026] According to a preferred embodiment of the method, forwarding of the transmitted enhanced image data to the corresponding screen is prevented if the validation indicates a still image, a cyclic image, or a significantly delayed image. This circumstance also prevents the operator from performing driving maneuvers based on incorrect information.

[0027] The respective unit, for example, the validation unit, can be implemented in hardware and / or software. In a hardware implementation, the respective unit can be embodied as a device or as part of a device, for example, as a computer, a microprocessor, or an FPGA. In a software implementation, the respective unit can be embodied as a computer program product, as a function, as a routine, as part of a program code, or as an executable object.

[0028] There are now numerous possibilities for advantageously designing and developing the method according to the invention. Reference is made to the claims subordinate to claim 1. A preferred embodiment of the method according to the invention will now be explained and described in more detail with reference to the drawing and the accompanying description. The drawing shows:

[0029] Fig.1 shows a schematic representation of a signal flow plan of the method for teleoperated control of the ground-based passenger vehicle, and Fig.2 shows a highly schematic representation of a teleoperated controllable passenger vehicle in a plan view.

[0030] Fig. 1 shows a method for remotely controlling a ground-based passenger vehicle 1 using a signal flow diagram. The passenger vehicle 1 itself is shown in Fig. 2. An operator controls the passenger vehicle 1 using a control unit 2 located spatially separate from the passenger vehicle 1.

[0031] The passenger vehicle 1 is, in particular, a road vehicle. In the passenger vehicle 1, all vehicle functions can be controlled via a built-in, so-called drive-by-wire system (DbW). The vehicle functions can therefore be controlled electrically. The vehicle functions are controlled via a central vehicle processing unit 4.F and with the aid of CAN bus data connections. The drive-by-wire system (DbW) has servomotors and / or actuators with which, for example, braking and acceleration impulses, as well as steering movements, can be implemented. The data sent from the control unit 2 to the passenger vehicle 1 are converted into control signals for the servomotors and / or actuators in the vehicle processing unit 4.F while the vehicle is driving.

[0032] The passenger vehicle 1 has at least two camera devices 30, 40, each with a camera 31, 41 and an integration unit 32, 42. The camera 31, 41 provides image data BD1, BD2 based on a recording of camera images. The integration unit 32, 42 outputs extended image data eBD1, eBD2 based on an integration of a coded information block, which includes a source information Q specific to the respective camera 31, 41 and a time stamp Z specific to the recording. The extended image data eBD1, eBD2 are transmitted from the passenger vehicle 1 to the control unit 2.The image data BD1, BD2 and / or the extended image data eBD1, eBD2 are displayed on a display device 6 of the control unit 2 for the operator to control the passenger vehicle 1, allowing the operator to identify obstacles, road conditions, or traffic signs while driving. The extended image data eBD1, eBD2 are validated using the integrated information block by a validation unit 60 coupled to the display device 6.

[0033] Fig.1 and Fig.2 explicitly show two cameras, namely a first camera 31 and a second camera 41. Consequently, a first camera device 30 and a second camera device 40 with a first integration unit 32 and a second integration unit 42 are also provided. There is thus correspondingly first image data BD1, second image data BD2, first extended image data eBD1 and second, extended image data eBD2. It would also be conceivable to use just one camera or more than two cameras, e.g. from 3 to 12, preferably from 4 to 9, in particular 5 cameras. This would then result in a corresponding number of camera devices, integration units, image data and extended image data.

[0034] The enhanced image data eBD1, eBD2 are transmitted wirelessly via a vehicle antenna AF of the passenger vehicle 1 to a transmission antenna AU, and from the transmission antenna AU to the control unit 2. The transmission antenna AU is designed as a mobile radio antenna. The wireless transmission between the vehicle antenna AF and the transmission antenna AU preferably takes place via a 5G mobile radio network according to the 5G standard, which is symbolized here by a double arrow. Other transmission technologies are conceivable. The 5G standard ensures that the enhanced image data eBD1, eBD2 can be transmitted in real time, which is important for the operator to be able to control the passenger vehicle 1 safely.

[0035] The extended image data eBD1, eBD2 are transmitted by cable from the transmission antenna AU to a data input DE of the control unit 2. This cable transmission occurs, for example, via a wired Internet connection GL, in particular via a fiber optic cable.

[0036] The enhanced image data eBD1, eBD2 can also be transmitted wirelessly from the transmission antenna AU to a control unit antenna AK of control unit 2. The control unit antenna AK and the adjacent double arrow are therefore shown as optional with dashed lines. The control unit antenna AK is then part of the data input DE of control unit 2. Here, too, wireless transmission preferably takes place via the 5G mobile network according to the 5G standard, which is symbolized here by the dashed double arrow.

[0037] The information block is encoded in an area of ​​the extended image data eBD1, eBD2 that is invisible to the operator, in particular in a black-level area of ​​the extended image data eBD1, eBD2. Using the integration unit 32, 42, a hash value calculated from the image data BD1, BD2 is additionally encoded into the encoded information block. Using the integration unit 32, 42, a QR code is generated such that the QR code contains the source information Q and the timestamp Z in encoded form. It would also be conceivable to use another type of code instead of a QR code.

[0038] The QR code is encoded in an area of ​​the extended image data eBD1, eBD2 that is invisible to the operator, particularly in a black-level area of ​​the extended image data eBD1, eBD2. It is also conceivable, however, for the QR code to be human-readable, in which case the QR code is displayed with the image data BD1, BD2 in a specific color, preferably black, in a suitable size, and at a suitable position, e.g., in the upper left corner of the image data BD1, BD2.

[0039] By means of the integration unit 32, 42, a hash value calculated from the image data BD1, BD2 is additionally encoded into the QR code.

[0040] A respective camera device 30, 40 has a camera monitoring device 32, 42, which includes the integration unit 32, 42. For reasons of clarity, the respective camera monitoring device is also provided with the reference numeral 32 or 42. The image data BD1, BD2 and / or the extended image data eBD1, eBD2 are transmitted from the camera 31, 41 to the camera monitoring device 32, 42 and from the camera monitoring device 32, 42 to the vehicle antenna AF via a respective image transmission interface CL, in particular via camera links.

[0041] The validation unit 60 and the respective integration unit 32, 42 are preferably time-synchronized using a common time base. The common time base is correlated, for example, with a time of the camera monitoring device 32, 42 and a time of a screen monitoring device 71, 72. Additionally or alternatively, the common time base can also be provided by an external source (not shown).

[0042] The display device 6 has at least two screens, namely a first screen 21 and a second screen 22. The respective screen 21, 22 is coupled to the data input DE via a screen monitoring device, namely a first screen monitoring device 71 and a second screen monitoring device 72. The extended image data eBD1, eBD2 are transmitted from the data input DE to the screen monitoring device 71, 72 and from the screen monitoring device 71, 72 to the screens 21, 22 by means of a respective digital image transmission interface DVI, in particular via a digital visual interface. In particular, one screen 21, 22 is provided for each camera 31, 41, wherein preferably only the image data BD1, BD2 acquired by means of one of the cameras 31, 41 are displayed on each screen 21, 22.It is also conceivable to provide different numbers of cameras and screens and to transform the image data BD1, BD2 accordingly.

[0043] An image check with respect to a still image supplied by the respective camera 31, 41 or with respect to cyclic images in the extended image data eBD1, eBD2 is carried out by means of a comparison of hash values ​​transmitted by the extended image data eBD1, eBD2 and / or as a function of a fast Fourier transformation by means of the screen monitoring device 71, 72.

[0044] The validation unit 60 is connected to the screen monitoring device 71, 72 via an ETH interface, for example, via an Ethernet networking interface. The source information Q and the time stamp Z are extracted from the extended image data eBD1, eBD2 by means of the screen monitoring device 71, 72, and the extracted source information Q and the extracted time stamp Z are transmitted via the ETH interface to a control device 80 of the control unit 2 comprising the validation unit 60.

[0045] In contrast, the transmitted extended image data eBDI, eBD2 can also be branched off in parallel to the respective screen monitoring device 71, 72 in order to avoid, in particular, erroneous image outputs by the respective screen monitoring device 71, 72.

[0046] Depending on the validation performed by the validation unit 60, an action is initiated or executed by the control device 80.

[0047] The data sent from the control unit 2 to the passenger vehicle 1 for controlling the passenger vehicle 1 are transmitted in particular by means of the control device 80, via the transmission antenna AU and via the vehicle antenna AF to the vehicle computing unit 4.F.

[0048] An emergency braking of the passenger vehicle 1 is carried out if the validation indicates a display of an image from a wrong camera 31, 41 by the corresponding screen 21, 22 or if the validation indicates an occlusion of the corresponding camera 31, 41 or if the validation indicates a display of a still image by the corresponding screen 21, 22 or if the validation indicates a display of a cyclic image by the corresponding screen 21, 22 or if the validation indicates a display of a strongly delayed image by the corresponding screen 21, 22.

[0049] As the example in Fig. 1 shows, the first screen 21 should display the first, extended image data eBD1 of the first camera device 30 and thus of the first camera 31. However, if the validation carried out by the validation unit 60 indicates that the first extended image data eBD1 of the first camera device 30 is not currently being transmitted to the screen 21, but rather the second extended image data eBD2 of the second camera 41 of the second camera device 40, an emergency braking of the passenger vehicle 1 can be initiated, in particular by means of the control device 80. It is conceivable that the emergency braking is initiated automatically by means of the control device 80, or that an emergency braking signal is displayed by means of the control device 80 and, for example, one of the screens 21, 22 for the operator, who then carries out the emergency braking manually.

[0050] An overlay or a black image is displayed on the corresponding screen 21, 22 if the validation indicates that the corresponding camera 31, 41 is obscured.

[0051] The transmitted image data BD1, BD2 are marked as a freeze frame if the validation indicates a freeze frame display, a cyclic frame display, or a significantly delayed frame display. Marking as a freeze frame is possible via the corresponding screens 21, 22 themselves or via a separate error display device.

[0052] Forwarding of the transmitted extended image data eBD1, eBD2 to the corresponding screen 21, 22 is prevented if the validation indicates a display of a still image, a display of a cyclic image, or a display of a significantly delayed image. This prevention is performed, for example, by means of the control device 80 and / or the respective screen monitoring device 71, 72. List of reference symbols

[0053] 1 passenger car

[0054] 2 Control unit

[0055] 6 Display device

[0056] 21 first screen

[0057] 22 second screen

[0058] 30 first camera setup

[0059] 31 first camera

[0060] 32 first integration unit / camera surveillance device

[0061] 40 second camera setup

[0062] 41 second camera

[0063] 42 second integration unit / camera surveillance device

[0064] 60 validation units

[0065] 71 first screen monitoring device

[0066] 72 Screen monitoring device

[0067] 80 Control device

[0068] AF vehicle antenna

[0069] AU transmission antenna

[0070] AK control unit antenna

[0071] DE Data input of control unit 2

[0072] BD1 first image data

[0073] BD2 second image data eBD1 first, extended image data eBD2 second, extended image data

[0074] 5G (5G) mobile network

[0075] GL wired internet connection (fiber optic cable)

[0076] CL Camera Link

[0077] DVI Digital Visual Interface

[0078] ETH Ethernet networking interface

[0079] Q Source reference

[0080] From the Zeitstempel

Claims

Patent claims 1. Method for the teleoperated control of a ground-based passenger vehicle (1), wherein an operator controls the passenger vehicle (1) by means of a control unit (2) arranged spatially separately from the passenger vehicle (1), characterized in that the passenger vehicle (1) has at least two camera devices (30, 40), each with a camera (31, 41) and an integration unit (32, 42), wherein image data (BD1, BD2) based on a recording of camera images are provided by means of the camera (31, 41), wherein extended image data (eBD1, eBD2) based on an integration of a coded information block, which comprises a source information (Q) specific to the respective camera (31, 41) and a time stamp (Z) specific to the recording, are output by means of the integration unit (32, 42), wherein the extended image data (eBD1, eBD2) are transmitted from the passenger vehicle (1) to the control unit (2), wherein the image data (BD1 , BD2) and / or the extended image data (eBD1 ,eBD2) are displayed by means of a display device (6) of the control unit (2) for the operator to control the passenger vehicle (1), wherein the extended image data (eBD1, eBD2) are validated on the basis of the integrated information block by means of a validation unit (60) coupled to the display device (6).

2. Method according to claim 1, characterized in that the extended image data (eBD1, eBD2) are transmitted wirelessly by means of a vehicle antenna (AF) of the passenger vehicle (1) to a transmission antenna (AU) and from the transmission antenna (AU) to the control unit (2) be transferred.

3. Method according to claim 2, characterized in that the transmission antenna (AU) is designed as a mobile radio antenna and the extended image data (eBD1, eBD2) are transmitted to the transmission antenna (AU) via a mobile radio network (5G).

4. Method according to claim 2 or 3, characterized in that the extended image data (eBD1, eBD2) are transmitted by cable from the transmission antenna (AU) to a data input (DE) of the control unit (2).

5. The method according to claim 2 or 3, characterized in that the extended image data (eBD1, eBD2) are transmitted wirelessly from the transmission antenna (AU) to a control unit antenna (AK) of the control unit (2).

6. Method according to one of the preceding claims, characterized in that the information block is encoded in an area of ​​the extended image data (eBD1, eBD2) that is not visible to the operator, in particular in a black level area of ​​the extended image data (eBD1, eBD2).

7. Method according to one of the preceding claims, characterized in that by means of the integration unit (32, 42) a hash value calculated from the image data (BD1, BD2) is additionally encoded into the encoded information block.

8. Method according to one of claims 1 to 5, characterized in that a QR code is generated by means of the integration unit (32, 42) in such a way that the QR code has the source information (Q) and the time stamp (Z) in coded form.

9. Method according to the preceding claim, characterized in that the QR code is encoded in an area of ​​the extended image data (eBD1, eBD2) that is not visible to the operator, in particular in a black level area of ​​the extended image data (eBD1, eBD2).

10. The method according to claim 8 or 9, characterized in that by means of the integration unit (32, 42) a hash value calculated from the image data (BD1, BD2) is additionally encoded into the QR code.

11. Method according to the preceding claim, characterized in that a respective camera device (30, 40) has a camera monitoring device (32, 42) which comprises the integration unit (32, 42), wherein the image data (BD1, BD2) and / or the extended image data (eBD1, eBD2) are transmitted from the camera (31, 41) to the camera monitoring device (32, 42) and from the camera monitoring device (32, 42) to the vehicle antenna (AF) by means of a respective image transmission interface (CL), in particular by means of Camera Link.

12. Method according to one of claims 4 to 11, characterized in that the display device (6) has at least two screens (21, 22), wherein the respective screen (21, 22) is coupled to the data input (DE) via a screen monitoring device (71, 72), wherein the extended image data (eBD1, eBD2) are transmitted from the data input (DE) to the screen monitoring device (71, 72) and from the screen monitoring device (71, 72) to the screens (21, 22) by means of a respective digital image transmission interface (DVI), in particular via a digital visual interface.

13. Method according to the preceding claim, characterized in that an image check with regard to a still image supplied by the respective camera (31, 41) or with regard to cyclic images in the extended image data (eBD1, eBD2) is carried out by means of a comparison of hash values ​​transmitted by the extended image data (eBD1, eBD2) and / or as a function of a fast Fourier transformation by means of the screen monitoring device (71, 72).

14. The method according to claim 12 or 13, characterized in that the validation unit (60) is connected to the screen monitoring device (71, 72) via an interface (ETH), for example via an Ethernet networking interface, wherein the source information (Q) and the time stamp (Z) are extracted from the extended image data (eBD1, eBD2) by means of the screen monitoring device (71, 72) and the extracted source information (Q) and the extracted time stamp (Z) are transmitted via the interface (ETH) to a control device (80) of the control unit (2) having the validation unit (60).

15. Method according to the preceding claim, characterized in that an action is initiated or executed by means of the control device (80) depending on the validation carried out by the validation unit (60).

16. Method according to the preceding claim, characterized in that an emergency braking of the passenger vehicle (1) is carried out if the validation indicates a display of an image from a wrong camera (31, 41) by the corresponding screen (21, 22) or if the validation indicates an obscuration of the corresponding camera (31, 41) or if the validation indicates a display of a still image by the corresponding screen (21, 22) or if the validation indicates a display of a cyclic image by the corresponding screen (21, 22) or if the validation indicates a display of a strongly delayed image by the corresponding screen (21, 22).

17. Method according to claim 15 or 16, characterized in that an overlay or a black image is displayed on the corresponding screen (21, 22) if the validation indicates an occlusion of the corresponding camera (31, 41).

18. Method according to one of claims 15 to 17, characterized in that the transmitted image data (BD1, BD2) are marked as a still image if the validation indicates a display of a still image or a display of a cyclic image or a display of a strongly delayed image.

19. Method according to one of claims 15 to 18, characterized in that forwarding of the transmitted extended image data (eBD1, eBD2) to the corresponding screen (21, 22) is prevented if the validation indicates a display of a still image or a display of a cyclic image or a display of a strongly delayed image.

Images