RAIL VEHICLE AND VIDEO SYSTEM FOR A RAIL VEHICLE

Description

[0001] The invention relates to a system for monitoring rail vehicles, comprising: at least one analog video camera for capturing analog image signals from an exterior area of ​​the rail vehicle, which is designed to capture analog image signals against a dedicated direction of travel from at least one driver's cab of the rail vehicle; at least one analog monitor for at least one driver's cab of the rail vehicle for displaying the analog image signals from the analog video camera in real time.

[0002] The system can be used for the handling and operation of rail vehicles.

[0003] Furthermore, the invention relates to a rail vehicle with such a system for monitoring rail vehicles.

[0004] Instead of optical rearview mirrors located on the outside of a rail vehicle in the driver's cab area, appropriately oriented cameras and monitors can also be used. Cameras and monitoring screens for rail vehicles that replace conventional optical rearview mirrors are also known as "electronic rearview mirror systems." The cameras used for this purpose are typically mounted on the outside of the rail vehicle and oriented against the direction of travel to monitor the area behind the driver's cab and display it on a screen. The cameras capture at least those sections of the image that would also be visible to the driver using optical rearview mirrors.Most cameras, through appropriate positioning and lenses, capture larger areas of the exterior, eliminating the need for the train driver to change their seating position to see specific parts of the vehicle's exterior, as can sometimes be necessary with conventional optical rearview mirrors. The advantages of electronic rearview mirror systems over conventional optical mirrors include improved aerodynamics, a less fragile design, better visibility for the driver, and a more aesthetically pleasing appearance.

[0005] Electronic rearview mirror systems for cars with external cameras and screens in the passenger compartment are known from US 10,198,639 B2. CN 102098496 A discloses a type of rearview mirror system for rail vehicles that uses infrared cameras.

[0006] In order for manufacturers of rail vehicles to install electronic rearview mirror systems, these systems must meet certain requirements specified in standards or certifications. These requirements primarily concern the reliability of the electronic rearview mirror system and the real-time display of camera images. An example of a standard that defines the specific requirements for electronic rearview mirror systems is the German Tramway Construction and Operating Regulations (BOStrab) of October 10, 2019. According to standard E / ECE / 324 / Rev.1 / Add.45 / Rev.6-E / ECE / TRANS / 505 / Rev.1 / Add.45 / Rev.6 §6.2.2.3.4.3, real-time for a camera-based monitor system means that the latency between the camera capturing an image and its display on the screen must not exceed 200 ms at a room temperature of 22°C + / -5°C. A method for measuring latency is known from EP 3 483 617 A1.

[0007] To meet the aforementioned requirements regarding real-time performance and reliability, analog electronic rearview mirror systems with analog video cameras and analog monitors are typically used. This is because, unlike digital electronic rearview mirror systems, analog systems eliminate the need for digitization, compression, decoding / encoding, fragmented data packet transmission, buffering, and data processing. As a result, the latency between capturing a camera image and displaying it on a screen remains low and deterministic. Furthermore, with digital electronic rearview mirror systems using bus connections, other devices can potentially block the bus, further increasing or causing fluctuations in latency.To minimize latency in a digital electronic rearview mirror system, it must be specifically adapted and equipped with special, and therefore expensive, components (special or exclusively used switches, etc.). Even with such an adapted digital electronic rearview mirror system, demonstrating compliance with the required real-time criterion is generally difficult to establish and fulfill due to the aforementioned processes (digitization, compression, etc.). For these reasons, analog electronic rearview mirror systems are predominantly used in rail vehicles, as is the case with the rail vehicle described at the beginning.

[0008] On curves or at curved platforms, it is difficult for drivers of long or multiple-unit trains to maintain a clear view. This problem exists not only with conventional optical rearview mirrors but also with state-of-the-art electronic rearview mirror systems. It would therefore be desirable to have a train and a system of the type mentioned above that offer improved visibility for the driver.

[0009] Analog rearview mirror systems with analog video cameras and analog monitors have the disadvantage that signal transmission can be negatively affected by strong electric and magnetic fields or by moving mechanical connectors, such as those used in couplings for multiple-unit trainsets, potentially leading to a loss of image quality. Another disadvantage of analog systems is their limited flexibility. Any system change requires recertification of the rearview mirror system, incurring significant costs and additional effort. Digital rearview mirror systems, on the other hand, have the disadvantage of inherent system processes described above, such as digitization, compression, data transmission via a bus system like Ethernet, and the decoding and encoding of camera images., have a comparatively high latency and are therefore not "real-time capable" or only with very high effort, as required by the standards and certifications for electronic rear-view mirror systems of rail vehicles.

[0010] Current technology includes rail vehicles with exclusively analog and exclusively digital rearview mirror systems. A rearview mirror system with exclusively analog video cameras and analog monitors is known from the company "I+ME ACTIA" (NPL number: XP055946435). A rearview mirror system with exclusively digital video cameras and digital monitors is known from the company "EYYES" (NPL number: XP055946465; also available at https: / / web.archive.org / web / 20210723165026 / https: / / www.eyyes.com / products / rai-leye-4-0 / ).

[0011] In light of the foregoing, the object of the invention is to at least partially mitigate or even completely eliminate the disadvantages of the prior art. Preferably, the object of the present invention is to improve the visibility for a train driver in curved stations and on curves in a rail vehicle equipped with an electronic rearview mirror system, without negatively affecting the safety-relevant components of the electronic rearview mirror system with regard to latency and reliability. This object is achieved by a system according to claim 1. A rail vehicle with such a system is specified in claim 2. Preferred embodiments are specified in the dependent claims.

[0012] According to the invention, the system of the type mentioned at the outset is characterized by at least one digital video camera for capturing digital image signals from the exterior of the rail vehicle; and at least one digital monitor for the at least one driver's cab for displaying the digital image signals from the at least one digital video camera.

[0013] The system according to the invention is described below with reference to a preferred application in a rail vehicle. In a rail vehicle of the type described above, at least one digital video camera is preferably provided on the outside of the rail vehicle for capturing digital image signals of the exterior of the rail vehicle. The at least one driver's cab also has at least one digital monitor for displaying the digital image signals from the at least one digital video camera. In the rail vehicle according to the invention, an analog electronic rearview mirror system for improving the driver's visibility—particularly in curves and curved stations or in multiple traction—is thus enhanced by digital components.The electronic rearview mirror system thus consists of an analog and a digital component: The safety-relevant components of the electronic rearview mirror system, which replace the conventional optical rearview mirrors of the rail vehicle, are formed by at least one analog video camera and at least one analog monitor, which is preferably directly connected to the at least one analog video camera. The analog monitor is designed to display analog video signals supplied to it. For example, a TFT (thin-film transistor) screen with at least one analog video signal input can be used as the analog monitor. Of course, other screen technologies can also be used. The analog monitor can therefore also be referred to as an analog signal monitor.The use of analog electronic components without intermediate data storage and the direct connection of the camera to the monitor ensures low latency and high reliability, as required by standards and certifications. The non-safety-related components of the rearview mirror system, which serve to further enhance visibility and redundancy, consist of at least one digital video camera and at least one digital monitor. For these components, minimal latency and maximum reliability are not required, as they are additional components that would not be present in conventional rail vehicles with standard optical rearview mirrors. The digital monitor is designed to display the digital video signals it receives. For example, a TFT screen with at least one digital video signal input can be used as the digital monitor.Of course, other screen technologies can also be used. The digital monitor can therefore also be called a digital signal monitor. The digital component of the electronic rearview mirror system does not need to meet any special safety-related requirements. Advantageously, by expanding the analog electronic rearview mirror system with digital components, the driver's view can be improved without negatively affecting the safety-relevant analog components. The digital components are not subject to such high demands regarding latency and reliability, which is why their costs can be kept low. At the same time, the digital components are flexible and provide redundancy.The invention thus creates an electronic rearview mirror system that, on the one hand, meets the specific requirements regarding real-time capability and reliability stipulated in standards and certifications for electronic rearview mirror systems, and on the other hand, improves the driver's visibility in a simple, flexible, and cost-effective manner. By using at least one analog video camera, oriented opposite the dedicated direction of travel of the driver's cab, and at least one analog monitor, it is ensured that the driver can see the video signals in real time, i.e., with a maximum delay of 200 ms between the acquisition of the video signals and their display on the analog monitor. To keep latency low, the at least one analog video camera can be connected directly to the at least one analog monitor, in particular without an intervening crossbar.It is preferred that at least one analog video camera is arranged on an exterior surface of the rail vehicle. Several analog video cameras can be provided, each assigned to one driver's cab. Each analog video camera can be directly connected to its own analog monitor. In a particularly preferred embodiment, each driver's cab of the rail vehicle is assigned at least two analog video cameras and has at least two analog monitors. In particular, it can be provided that each driver's cab is assigned two analog video cameras arranged on opposite exterior surfaces of the rail vehicle – one for the left and one for the right exterior surface. The analog video cameras are oriented opposite to the designated direction of travel. The orientation can be, but need not be, parallel to the direction of travel.Each analog video camera transmits its analog video signals to a dedicated analog monitor in the driver's cab to which it is assigned. "Assigned to a driver's cab" means that the analog video signals from the analog camera can be displayed on an analog monitor in the driver's cab, and that the analog camera is located within the driver's cab area. At least one digital video camera can also be assigned to the driver's cab. Digital video cameras assigned to a driver's cab are located within the driver's cab area. The rail vehicle can have two driver's cabs for different directions of travel. The driver's cabs can be configured identically with regard to their camera systems.Each driver's cab can be equipped with one analog video camera for the left side (as viewed in the direction of travel) and one analog video camera for the right side (as viewed in the direction of travel). Each driver's cab can therefore have a left and a right analog monitor. The right side of a driver's cab (as viewed in the direction of travel) is referred to below simply as the "right side." The same applies to the "left side." The right analog monitor can be directly connected to the analog video camera for the right side. The left analog monitor can be directly connected to the analog video camera for the left side. The analog monitor can be a monitor for displaying analog video data or a hybrid monitor for displaying both analog and digital video signals. Thus, an analog monitor and a digital monitor can be combined in a single device.The hybrid monitor can, for example, have one or more TFT screens with at least one analog and at least one digital video signal input. Of course, other screen technologies can also be used. In one embodiment, the display of analog and digital video signals can be switched on a hybrid monitor with one screen. The at least one analog video camera does not have to be aligned parallel to the dedicated direction of travel, but can also be positioned at an angle to it, for example, downwards. The only important thing is that the analog video camera captures the area opposite the dedicated direction of travel. The at least one digital video camera is configured to generate digital video signals and transmit them to the at least one digital monitor, preferably to all digital monitors of the rail vehicle.When multiple rail vehicles are coupled together, the digital video signals can also be transmitted to digital monitors on the coupled vehicles. For example, the digital video signals from the digital video cameras can be displayed picture-in-picture, or the train driver can select which digital video signals, i.e., which digital video camera, to view. Digital monitors and digital video cameras can be connected via a network, such as an Ethernet network. To connect one or more digital video cameras to one or more digital monitors, or to establish a network, one or more (Ethernet) switches can be used. The digital video cameras and the digital monitors can be connected to the switch(es). In this way, the digital video signals can be displayed on multiple digital monitors simultaneously.As with analog video cameras, digital video cameras can be provided for the left and right sides of the vehicle. Similarly, a digital monitor can also be provided for the left and right sides. The analog and digital video signals can be displayed simultaneously on the monitors. The at least one digital video camera can be oriented in various ways to capture the exterior of the rail vehicle. For example, the at least one digital video camera can be tilted in the designated direction of travel, against the designated direction of travel, or downwards at an angle to the designated direction of travel. Preferably, an analog monitor and a digital monitor can be combined in a hybrid monitor for displaying analog and digital signals. In a preferred embodiment, one hybrid monitor is used for the left side and one for the right side of the rail vehicle.The rail vehicle could be, for example, a tram, a passenger train, or a subway. The exterior of the rail vehicle refers to its surroundings.

[0014] Directional information refers to the intended operating condition of the rail vehicle. Unless otherwise specified, the directional terms "left" and "right" refer to the dedicated direction of travel of a driver's cab.

[0015] In one embodiment of the invention, at least one digital video camera is preferably provided on the outside of the rail vehicle. This camera is assigned to the at least one driver's cab and is configured to capture digital video signals opposite the dedicated direction of travel of the at least one driver's cab. The at least one digital video camera is configured to capture digital video signals from the exterior of the rail vehicle. The at least one digital video camera can be arranged on the outside of the rail vehicle or inside the rail vehicle, for example, in a projection or bulge on the outside of the rail vehicle. The at least one digital video camera is arranged in the area of ​​the driver's cab to which it is assigned. Preferably, at least one, and in particular at least two, first digital signal cameras are assigned to each driver's cab.Each driver's cab, or at least one driver's cab, can be assigned a first digital signal camera for the left side and / or a first digital signal camera for the right side of the cab. The first digital video camera can transmit the digital image signals to at least one digital monitor, or in one embodiment, to every digital monitor in all driver's cabs. The first digital video camera does not need to be aligned parallel to the dedicated direction of travel, but can also be positioned at an angle to it. As with the analog video camera, the only important factor is that the area opposite the dedicated direction of travel is captured. In the event of a failure of the analog video camera, the first digital video camera provides redundancy, thereby increasing the system's availability.

[0016] It is preferred if the at least one analog video camera and the at least one first digital video camera are essentially aligned in the same way and preferably configured to capture an essentially identical image area. It is particularly preferred if, in a driver's cab, the number of first digital video cameras corresponds to the number of analog video cameras. However, the number of cameras can also differ. Each analog video camera can be assigned a digital video camera that is essentially aligned in the same way. Preferably, an analog video camera and its assigned digital video camera capture an essentially identical image area. Due to the capture of essentially identical image areas, in the event of a failure of an analog video camera, a digital video camera can be used as redundancy, thereby significantly increasing the availability of the system.

[0017] A particularly simple and stable design is achieved when the at least one analog video camera and the at least one first digital video camera are arranged in a common camera housing, which is preferably attached to the outside of the rail vehicle. The camera housing is preferably located in the area of ​​the at least one driver's cab. It is preferred that each driver's cab has one camera housing on the left and one on the right side. Thus, each driver's cab has one analog video camera and one on the right side.

[0018] In a particularly preferred embodiment of the invention, at least two analog video cameras and at least two first digital video cameras are assigned to the at least one driver's cab. The analog video cameras are either directly connected to a common analog monitor or each analog video camera is directly connected to an analog monitor in the at least one driver's cab assigned to the corresponding analog video camera. An analog video camera and a first digital video camera are provided on the left and right sides, respectively. According to the invention, the driver's cab also has at least one or more digital monitors with which the digital video signals from the digital video cameras can be displayed. A digital monitor and an analog monitor can be components of a hybrid monitor for displaying analog and digital video signals.

[0019] Preferably, a second digital video camera and / or at least one second analog video camera is provided on an exterior surface of the rail vehicle, wherein the second digital video camera and / or the second analog video camera are / are assigned to the at least one driver's cab and are / are directed parallel to the dedicated direction of travel or downwards at an angle to the dedicated direction of travel, preferably substantially perpendicular downwards to the dedicated direction of travel, or towards a passenger door. If the cameras are at least partially directed downwards and capture a ground area, these cameras can also be referred to as a ground camera due to their orientation. A ground camera can also be directed at least partially forwards in the dedicated direction of travel or backwards opposite to the dedicated direction of travel. The at least one ground camera is configured to capture digital image signals from the exterior of the rail vehicle.The at least one floor camera can be arranged on the outside of the rail vehicle or inside the rail vehicle, for example, in a projection or recess on the outside of the rail vehicle. Preferably, each driver's cab is assigned at least one, and in particular at least two, second analog or digital video cameras. Each driver's cab can be assigned a second analog and / or digital video camera for the left side and / or a second analog and / or digital video camera for the right side of the cab. The digital video signals from a second digital video camera can be displayed on the at least one digital monitor, preferably on each digital monitor in all driver's cabs of the rail vehicle. If a second analog video camera is provided, a further analog monitor can be provided in the driver's cab assigned to it, which can display the analog video signals from the second analog video camera.

[0020] In one embodiment of the invention, the at least one second digital video camera and / or the at least one second analog video camera are also arranged in the common camera housing. If, as described, two second analog or digital video cameras are assigned to each driver's cab, these can each be arranged in a camera housing on the left and right side of each driver's cab.

[0021] To further improve the visibility for the train driver, particularly in areas with limited visibility, at least one third digital video camera can preferably be provided on the exterior of the train. This camera is assigned to the at least one driver's cab and is configured to capture digital video signals in the dedicated direction of travel of that cab. The at least one third digital video camera is designed to capture digital video signals from the exterior of the train. The at least one third digital video camera can be located on the exterior of the train or inside the train, for example, in a projection or recess on the exterior of the train. The at least one third digital video camera is located in the area of ​​the driver's cab to which it is assigned.As already explained in connection with the at least one first digital video camera, each driver's cab can be assigned at least one, preferably at least two, third digital video cameras. It is particularly preferred if each driver's cab is assigned a third digital signal camera for the left side and / or a third digital signal camera for the right side of the cab. The at least one third digital video camera can transmit the digital video signals to at least one digital monitor, preferably to each digital monitor in all driver's cabs.

[0022] To protect at least one third digital video camera, it can be housed in a shared camera housing. As mentioned previously, a shared camera housing can be located on the left and right outer sides of each driver's cab.

[0023] To facilitate the train driver's overview of passengers boarding and alighting, at least one fourth digital video camera can preferably be provided on the exterior of the train in the passenger compartment area. This camera is preferably configured to capture digital video signals from at least one passenger door or from a floor area. The at least one fourth digital video camera can also be oriented substantially in one of the train's directions of travel. The at least one fourth digital video camera is configured to capture digital video signals from the exterior of the train. The at least one fourth digital video camera can be located on the exterior of the train or inside the train, for example, in a projection or bulge on the exterior of the train.The fourth digital video camera can be mounted, in particular, on the outer side where at least one passenger door is located. It is preferred if at least one fourth digital video camera is mounted on both outer sides of the rail vehicle.

[0024] It is preferred if the digital image signals of all digital video cameras of the rail vehicle and any connected rail vehicles can be displayed on at least one digital monitor.

[0025] In one embodiment of the invention, at least one interior camera designed as a digital video camera is provided in the passenger compartment, preferably on the ceiling of the passenger compartment. The interior camera can also transmit the image signals to at least one, preferably all, digital monitors.

[0026] To enable accident reconstruction, a video recording device may be provided, configured to store recordings from at least one digital video camera on the exterior of the rail vehicle. The video recording device may also store video signals from at least one interior camera.

[0027] The rail vehicle can be equipped with two identically designed driver's cabs, each assigned to a different direction of travel. Viewed from the center of the rail vehicle, the directions of travel point in opposite directions. The driver's cabs are located at opposite ends of the rail vehicle.

[0028] The rail vehicle can be connected to at least one other identical rail vehicle via a coupling. This forms a rail vehicle train. The digital video signals from the digital video cameras of the individual rail vehicles can be exchanged via electrical connectors at the coupling, so that, in a preferred embodiment, all digital video signals from all digital video cameras can be displayed on all digital monitors. For example, video signals from a first digital video camera assigned to one driver's cab can be displayed on a digital monitor of another driver's cab.

[0029] It is advantageous if the at least one analog monitor and the at least one digital monitor form components of a hybrid monitor for displaying digital and analog video signals. In one embodiment, the display of analog and digital video signals can be switched on a hybrid monitor with a single screen. The at least one driver's cab can have at least two hybrid monitors, in particular one for the video cameras on the left side and one for the video cameras on the right side of the rail vehicle.

[0030] The problem mentioned at the outset is solved, as already described in connection with the rail vehicle, by a system according to claim 1. The system comprises at least the following: at least one analog video camera for capturing analog image signals from an exterior area of ​​the rail vehicle, which is configured to capture analog image signals opposite to the direction of travel of the rail vehicle; at least one analog monitor for a driver's cab of the rail vehicle for displaying the analog image signals of the analog video camera in real time; at least one digital video camera for capturing digital image signals from the exterior area of ​​the rail vehicle; and at least one digital monitor for the driver's cab for displaying the digital image signals of the at least one digital video camera.

[0031] Regarding the advantages and design of the system, reference is made to the above descriptions of the rail vehicle according to the invention. All features of the rail vehicle can be transferred to the system accordingly. In particular, the system can, for example, have at least one first, second, third, and / or fourth digital video camera of the type described above. The rail vehicle can have at least one, preferably at least two, driver's cabs. It is preferred if the system has two analog monitors for each driver's cab. It is also preferred if the system has two analog video cameras as well as two first and two third digital video cameras per driver's cab. Two second digital video cameras can also be provided per driver's cab. Fourth digital video cameras can, for example, be arranged on the outside of the rail vehicle.

[0032] The invention will be explained in more detail below with the aid of figures, to which it is not, however, limited. The figures show: Fig. 1 Rail vehicles with two driver's cabs each in multiple traction in side view; Fig. 2 Rail vehicles, each with a driver's cab, in multiple traction, in side view; Fig. 3 a block diagram for the wiring of an electronic rearview mirror system; Fig. 4 a common camera housing according to a first embodiment; and Fig. 5 a common camera housing according to a second embodiment.

[0033] Fig. 1 Figure 1 shows two identical, interconnected rail vehicles 1, which in the illustrated embodiment constitute a tram 2. Each rail vehicle 1 has a passenger compartment 3 and two driver's cabs 4 at opposite ends of the rail vehicle 1. Each driver's cab 4 has a dedicated direction of travel 5a, 5b. The directions of travel 5a and 5b are opposite to each other. Passengers can board the passenger compartment 3 via passenger doors 6.

[0034] The rail vehicles 1 have an electronic rearview mirror system 7 instead of conventional optical rearview mirrors. Each driver's cab 4 is assigned two analog video cameras 8r, 81 on opposite outer sides 50, which are oriented against the dedicated direction of travel 5a, 5b of the assigned driver's cab 4. Fig. 1 Only one exterior surface 50 of the rail vehicle 1 is shown, and thus only one analog video camera 8r, 81 per driver's cab 4, oriented against the direction of travel 5a, 5b, is visible. The non-visible exterior surface 50 is essentially identically configured with regard to the cameras. The analog video cameras 8r, 8l assigned to a driver's cab 4 are located in the area of ​​their respective driver's cab 4. The analog video cameras 8r, 81 are housed together with digital video cameras 9 (to be described in more detail later) in a common camera housing 10, which is mounted on the exterior surface 50 of the rail vehicle 1. The two analog video cameras 8r, 81 assigned to a driver's cab 4 are mounted on opposite outer sides 50 of the rail vehicle 1, which is why, viewed in the direction of travel 5a, 5b of the respective driver's cab 4, one can speak of an analog video camera 81 for the left side and an analog video camera 8r for the right side (cf.also . Fig. 3 ).

[0035] Fig. 3 schematically shows the structure of an electronic rearview mirror system 7. As in Fig. 3 As shown, two analog monitors 11r and 111 are arranged in driver's cab 4 to display the analog video signals recorded by the analog video cameras 8r and 8l. The analog monitors 11r and 11l are each part of a hybrid monitor 51r and 511 for displaying digital and analog video signals. Each analog video camera 8r and 8l is directly connected, specifically without an intermediate crossbar, to an analog monitor 11r and 111, respectively, and thus can be referred to as a right analog monitor 11r and a left analog monitor 111, or a left analog monitor 511 and a right hybrid monitor 51r. This allows a train driver (not shown) to monitor the rear exterior area 12 in the direction of travel 5a, 5b on the right by looking at the right analog monitor 11r and the rear exterior area 12 in the direction of travel on the left by looking at the left analog monitor 111.The image signals captured by the analog video cameras 8r, 81 are reliably displayed in real time, i.e., with a latency of less than 200 ms, on the analog monitors 11r, 111. This ensures compliance with the requirements stipulated by the relevant standards and certifications, which is difficult or even impossible to achieve with digital systems.

[0036] In curved sections of track or on curves, the problem of limited visibility for the train driver arises, particularly with long rail vehicles 1 or with multiple rail vehicles 1 operating in multiple traction. According to the invention, therefore, at least one digital video camera 9 is provided for capturing digital image signals from the exterior 12 of the rail vehicle 1, as well as at least one digital monitor 13r, 13l for displaying the digital image signals from the at least one digital video camera 9. The digital monitors 13r, 13l can also be components of the hybrid monitors 51r, 511 for displaying digital and analog signals. Preferably, a left 511 and a right hybrid monitor 51r are arranged in the driver's cabs 4. The left hybrid monitor 511 comprises a left digital monitor 13l, and the right hybrid monitor comprises a right digital monitor 13r.The digital monitors 13r and 13l can display the digital video signals from the digital video cameras 9, which is particularly advantageous for long rail vehicles 1 or for rail vehicles 1 operating in multiple traction. The signals from the digital video cameras 9 can be routed to the digital monitors 13r and 13l via one or more switches 54. For example, digital video signals from digital video cameras 9 on the right can be displayed on the right digital monitor 13r. The left digital monitor 13l can display the video signals from digital video cameras 9 on the left. The captured digital video signals can be displayed, for example, in picture-in-picture mode, or the train driver can select a specific digital video camera 9. The additional arrangement of the digital video cameras 9 and the digital monitors 13r and 13l advantageously improves the train driver's overview.Since the requirements of standards and certifications are already met by the analog component of the electronic rearview mirror system 7, consisting of analog video cameras 8r, 81 and analog monitors 11r, 111, real-time capability and high reliability are not required for the digital components. Furthermore, the analog components are not negatively affected because they are separated from the digital components.

[0037] In the illustrated embodiment, each driver's cab 4 of the rail vehicle 1 is assigned two first digital video cameras 14r, 141, which are mounted on opposite outer sides 50 of the rail vehicle 1. Therefore, when viewed in the direction of travel 5a, 5b of the respective driver's cab 4, one can speak of a first digital video camera 14l for the left side and a first digital video camera 14r for the right side. The first digital video cameras 14r, 141, similar to the analog video cameras 8r, 81, are configured to capture digital image signals opposite to the dedicated direction of travel 5a, 5b of the driver's cab 4 to which they are assigned. The first digital video cameras 14r, 141 are also housed in the common camera housings 10.The analog video cameras 8r, 81 for the right / left side and the first digital video cameras 14r, 141 for the right / left side of a driver's cab 4 are essentially aligned in the same way and preferably designed to capture an essentially identical image section (except for the offset of the two cameras from each other).

[0038] To better monitor the floor area of ​​the driver's cabs, the illustrated embodiment also includes floor cameras 15r, 15l. These floor cameras at least partially capture the floor of the exterior area 12. The floor cameras 15r, 15l are oriented downwards at an angle to the directions of travel 5a, 5b. The floor cameras 15r, 15l can be oriented vertically downwards or at an angle other than 90° to the direction of travel 5a, 5b. In the illustrated embodiment, the floor cameras are inclined at an angle other than 90° to the direction of travel 5a, 5b, slightly towards the dedicated direction of travel 5a, 5b of the driver's cab 4. The floor cameras 15r, 15l can also be inclined at an angle other than 90° to the direction of travel 5a, 5b, slightly opposite to the dedicated direction of travel 5a, 5b. In the embodiment shown, the ground cameras 15r, 15l are also housed in the common camera housings 10.Depending on the driver's cab 4 and its direction of travel 5a, 5b, the ground cameras 15r, 15l can also be configured as either ground cameras 15l for the left side or ground cameras 15r for the right side. The ground cameras 15 can be either second analog video cameras 52r, 521 or second digital video cameras 16r, 16l. In the illustrated embodiment, both second analog video cameras 52r, 521 and second digital video cameras 16r, 16l are provided on the left and right sides of the driver's cab, capturing essentially the same field of view. The digital video signals from the second digital video cameras 16r, 16l can be displayed on the digital monitors 13r, 13l. The analog video signals from the second analog video cameras 52r, 521 can be displayed on the analog monitors 11r, 111.

[0039] In the illustrated embodiment, the rail vehicle 1 has a coupling 21 at one end for coupling with another, identical rail vehicle 1. Advantageously, the digital video signals from the digital video cameras 10 can be transmitted via the coupling 21 using connectors without significant losses, whereas with analog video signals, this is only possible with considerable effort and loss due to mechanical stress on the connectors and high electrical and magnetic fields. The advantageous use of digital signals allows the train driver to monitor the area outside 12 of the coupled rail vehicles 1 using the digital video cameras 9. The digital video signals from the digital video cameras 9 can be displayed on the digital monitors 13 in the driver's cabs 4.For example, it is possible to reproduce a digital image signal from a digital video camera of another coupled rail vehicle 1 in a driver's cab.

[0040] Fig. 2 shows an embodiment in which the connected rail vehicles 1 each have only one driver's cab 4.

[0041] Fig. 4 and Fig. 5 show different forms of common camera housings. In Fig. 4 Inside the camera housing 10 are provided an analog video camera 81, a first digital video camera 141 and a ground camera 15l. The ground camera 15l can be analog or digital.

[0042] In Fig. 5 Inside the camera housing 10 are provided an analog video camera 8, a first digital video camera 14, a second analog video camera 521 and a second digital video camera 16l.

Claims

1. System (7) for monitoring rail vehicles (1), comprising: at least one analog video camera (8r, 8l) for capturing analog image signals of an exterior area (12) of the rail vehicle (1), which is configured to capture analog image signals opposite to a dedicated direction of travel (5a, 5b) of at least one driver's cab (4) of the rail vehicle (1); at least one analog monitor (11r, 11l) for the at least one driver's cab (4) of the rail vehicle (1) for reproducing the analog image signals of the analog video camera (8r, 81) in real time; characterized by at least a digital video camera (9) for capturing digital image signals of the exterior area (12) of the rail vehicle (1); and at least one digital monitor (13r, 13l) for the at least one driver's cab (4) for reproducing the digital image signals of the at least one digital video camera (9).

2. Rail vehicle (1), in particular tram (2), comprising: a passenger compartment (3) for persons with at least one passenger door (6) for boarding and alighting of the persons; at least one driver's cab (4) for a dedicated direction of travel (5a, 5b) of the rail vehicle (1); and a system (7) according to claim 1, wherein the at least one analog video camera (8r, 8l) for capturing analog image signals of an exterior area (12) of the rail vehicle (1) is associated with the at least one driver's cab (4) and is configured to capture analog image signals opposite to the dedicated direction of travel (5a, 5b) of the at least one driver's cab (4); and the at least one analog monitor (11r, 11l) for reproducing the analog image signals of the analog video camera (8r, 81) in real time is arranged in the at least one driver's cab (4); characterized in that the at least one digital video camera (9) for capturing digital image signals of the exterior area (12) of the rail vehicle (1) is preferably provided on the outer side (50) of the rail vehicle (1) and the at least one digital monitor (13r, 13l) for reproducing the digital image signals of the at least one digital video camera (9) is arranged in the at least one driver's cab (4).

3. Rail vehicle (1) according to claim 2, characterized in that preferably on an outer side (50) of the rail vehicle (1) at least one first digital video camera (14r, 141) is provided, which is associated with the at least one driver's cab (4) and which is configured to capture digital image signals opposite to the dedicated direction of travel (5a, 5b) of the at least one driver's cab (4).

4. Rail vehicle (1) according to claim 3, characterized in that the at least one analog video camera (8r, 81) and the at least one first digital video camera (14r, 141) are oriented substantially identically and are preferably configured to capture a substantially identical image section.

5. Rail vehicle (1) according to claim 4, characterized in that the at least one analog video camera (8r, 81) and the at least one first digital video camera (14r, 141) are arranged in a common camera housing (10), which is preferably attached to an outer side (50) of the rail vehicle (1).

6. Rail vehicle (1) according to any one of claims 3 to 5, characterized in that at least two analog video cameras (8r, 81) and at least two first digital video cameras (14r, 141) are associated with the at least one driver's cab (4), wherein the analog video cameras (8r, 8l) are connected directly to a respective analog monitor (11r, 111) of the at least one driver's cab (4) that is associated with the corresponding analog video cameras (8r, 8l).

7. Rail vehicle (1) according to any one of claims 2 to 6, characterized in that at least preferably on an outer side (50) of the rail vehicle (1) a second digital video camera (16r, 16l) and / or at least one second analog video camera (52r, 521) is / are provided, wherein the second digital video camera (16r, 16l) and / or the second analog video camera (52r, 521) is / are associated with the at least one driver's cab (4) and is / are directed substantially parallel to the dedicated direction of travel (5a, 5b) or downwards at an angle to the dedicated direction of travel (5a, 5b), preferably substantially perpendicular to the dedicated direction of travel (5a, 5b), or onto a passenger door (6).

8. Rail vehicle (1) according to claims 7 and 5, characterized in that the at least one second digital video camera (16r, 16l) and / or the at least one second analog video camera (52r, 521) is / are arranged in the common camera housing (10).

9. Rail vehicle (1) according to any one of claims 2 to 8, characterized in that preferably on an outer side (50) of the rail vehicle (1) at least one third digital video camera is provided, which is associated with the at least one driver's cab (4) and which is configured to capture digital image signals in the dedicated direction of travel (5a, 5b) of the at least one driver's cab (4).

10. Rail vehicle (1) according to claims 9 and 5, characterized in that the at least one third digital video camera is arranged in the common camera housing (10).

11. Rail vehicle (1) according to any one of claims 2 to 10, characterized in that preferably on an outer side (50) of the rail vehicle (1) at least one fourth digital video camera is provided in the region of the passenger compartment (2), which is preferably configured to capture digital image signals of at least one passenger door (6) or of a floor region of the rail vehicle (1).

12. Rail vehicle (1) according to any one of claims 2 to 11, characterized in that the digital image signals of a plurality of, preferably of all, digital video cameras (9) of the rail vehicle (1) and of optionally connected further rail vehicles (1) are reproducible on the at least one digital monitor (13r, 13l).

13. Rail vehicle (1) according to any one of claims 2 to 12, characterized in that two identically configured driver's cabs (4) are provided, which are associated with different directions of travel (5a, 5b).

14. Rail vehicle according to any one of claims 2 to 13, characterized in that the at least one analog monitor and the at least one digital monitor are combined in a common device, which comprises one or more TFT screens with at least one analog and at least one digital video signal input.

15. Rail vehicle combination, characterized in that at least two rail vehicles (1) according to any one of claims 2 to 14 are connected via a coupling (21).