WO2004096640A1

WO2004096640A1 - Aircraft comprising means for displaying the terrain below

Info

Publication number: WO2004096640A1
Application number: PCT/EP2004/050559
Authority: WO
Inventors: Jean-Yves Catros; Pierre NOËL
Original assignee: Thales
Priority date: 2003-05-02
Filing date: 2004-04-19
Publication date: 2004-11-11
Also published as: FR2854374B1; FR2854374A1

Abstract

The invention relates to the field of aeronautics. The invention consists in replacing all or part of the cabin windows of the aircraft with virtual windows (20) displaying a realistic image of the landscape that the passengers would see through a real window. The aforementioned images are provided by a pre-recorded database (10) which may contain pre-filmed or -photographed clear-weather images or ground data from which realistic synthesis images of the landscape below can be displayed. The images are provided according to the position of the aircraft in order to correspond effectively, and at least approximately, to the terrain below.

Description

AIRCRAFT PROVIDED WITH FLIGHT FIELD DISPLAY MEANS

The invention relates to the aeronautical field, and more particularly the interior equipment of an aircraft as well as its structure. The equipment covered by the present invention relates to passengers for airplanes carrying passengers. This equipment uses image display screens, which are increasingly installed on board aircraft and which can therefore be tried to adapt to new uses which are in addition to the uses already conventionally provided.

For the pilot, these screens are mainly used to display navigation or piloting aid information, including maps and relief plots in the form of contour lines. For passengers, the screens are intended for in-flight entertainment, to display either pre-recorded cinema films, television programs or information on the flight. The films are displayed either collectively on a screen intended for a series of passengers, or on an individual screen associated with each seat. There are also plans to provide passengers with video games displayed on individual screens, as well as interactive communication opportunities on the Internet.

It has also been proposed, for passengers, to provide on a collective screen an image provided by a camera placed at the front of the aircraft, this during the entire takeoff or landing phase. The passenger sees the runway during these phases.

Finally, sometimes inside the plane, collectively or on individual screens, a map of the path of the plane is displayed, on which the instantaneous position of the plane is shown, its course materialized by the orientation of the model on the plan, and the route it has followed up to this point.

In addition, it is considered that the passengers of commercial flights must have, for their comfort (to avoid air sickness) and to have a feeling of security, a possibility to look outside and if possible to see the horizon; this possibility is given by portholes distributed along the fuselage. The present invention firstly proposes that the aircraft portholes, for the use of passengers, be replaced by “virtual portholes” which are display screens on which the image of the landscape that the passenger if he had a real window. Consequently, according to one aspect of the invention, an aircraft is proposed carrying people (passengers and / or crew members), comprising means for displaying, on a screen constituting a virtual window near a person, a landscape of terrain dominated by the aircraft at the instant considered; this landscape is preferably one that the person could see on a clear day if they were looking outside the plane. The landscape is for example that which the person would see more or less in the direction of the gaze that they carry towards the virtual porthole. This direction can be a lateral direction (virtual porthole lateral next to the person, whether passenger or crew member, assuming that his seat is facing the front of the aircraft) or a frontal direction (porthole virtual seat in front of the person, the seat still assumed to be facing the front of the aircraft).

In its version providing the most realistic aspect of the landscape, one can display on a screen constituting a virtual porthole, therefore on a location of the interior wall of a fuselage not comprising a real porthole, the landscape filmed on a clear day by a camera observing the landscape more or less in the same direction as the viewer's gaze (laterally for a side wall window, frontally for a passenger or crew member looking in front of it). The aircraft could therefore be completely devoid of portholes. Developing this idea, the aircraft could be devoid of a front windshield and provided with a display screen and means for displaying on this screen the landscape that the passenger would see if there were a front windshield. Again, in its version providing the most realistic images, the screen can display an image filmed by a camera observing the landscape substantially in the general direction of the person's gaze (towards the front of the aircraft).

The absence of porthole and windshield, replaced by a porthole and a virtual windshield, are the ultimate version of the invention; in a mixed version, the landscape viewing screens are added to the actual windows and windshields rather than replacing them: the screens then serve to complement, for example to provide a visible landscape image even if the visibility conditions through the real window are poor In this case, the image provided on screen is preferably an image from a database (images taken by good weather for example) rather than by a camera filming the outdoor landscape in real time

In fact, according to a particularly important aspect of the invention, the landscape images which are displayed on these screens constituting virtual portholes or virtual windshields may not come from a camera filming live the landscape outside the aircraft. , but rather of a database The database can be embedded or not the broadband communication means can allow the database to be on the ground and a retransmission to the plane, taking into account the position of the plane to determine the images to display

In this case, in order to increase the functionalities of the aircraft, as regards the services rendered on board (for the passengers), or finally the improvement of the construction characteristics (for the aircraft itself), the present invention proposes that I aircraft be equipped with means to display at will realistic reconstructed images (not obtained by a camera placed under the aircraft) of the terrain overflown by I aircraft These images are intended for passengers for their comfort and distraction They are enslaved in real time to the geographic position of the aircraft

In other words, in this version, instead of providing passengers with images of the terrain overflown obtained by a camera placed under the plane, which requires expensive technical means if we want to have a lot of display possibilities we display according to I invention of realistic images from a database By realistic images, we mean images which, even if they are synthetic, are not symbolic (a relief map drawn in the form of a series of contour lines being considered here as symbolic and not realistic), that is to say that the passenger is led to believe that he has a real landscape before his eyes These images are raw images from the base, or images processed after extraction from the base , or synthetic images generated from the base But in all cases, the images displayed depend on the instantaneous position of the plane, and preferably they also depend on the attitude from the plane Consequently, according to one aspect of the invention, a passenger transport aircraft is provided comprising means for extracting data from a prerecorded database as a function of the instantaneous position of the aircraft, and means for providing, to from the database and as a function of the instantaneous position of the aircraft, realistic images representing the terrain overflown at this instant by the aircraft, and means for displaying these images.

The images are extracted from the database directly or indirectly. For example, if the images to be displayed are images obtained by a camera, the database may be a database of realistic prerecorded images, or of sequences photographed by another aircraft, for example images filmed on the same route on a day of good visibility. The sequences are therefore filmed beforehand by a specialized aircraft and used later in a commercial flight. The aircraft may furthermore comprise calculation means for carrying out modifications of the images, in particular for providing by calculation a modified image representing a landscape from a viewing angle which is related to the attitude of the aircraft, while the image stored in the database can be an image taken from another angle of view (typically the database could only store images corresponding to a vertical view photographed from a flat plane, while the passenger should see a tilted image if the plane carrying it is in a tilted turn at the same location).

The calculation means preferably also include means for enlarging the image, analogous to a camera "zoom", to display a more or less large portion of a stored image.

The stored images can come from different sources: video sequences taken from an airplane on different routes, aerial shots, visible images taken by satellites, images obtained by non-visible radiation (radar images, images infrared) but made visible on the screen, or finally purely synthetic images (developed from a terrain relief database and synthesized according to the position of the aircraft and its attitude). These different images can be combined in the calculation of the image which will be displayed on the user's screen. Other image processing can be envisaged (color processing, text or image inlays, etc.).

The images are projected either on a screen placed near a passenger. It is believed that if each passenger has a comfortable view (individual or collective) on a screen which displays the landscape overflown, this screen could make the portholes intended for passengers useless, even if in accordance with the invention, the images displayed are not the actual images (which a camera could see under the plane) but synthetic images or images from prerecorded sequences. The structure of the aircraft can then be simplified by eliminating the portholes, without however causing passengers to suffer from air sickness, to which the occupants of aircraft without windows are frequently subject because they have not of inertial reference of outside.

In a very simplified variant, but possibly being sufficient for the needs of the passengers, the images include a video sequence of images of the terrain overflown and only the start of the sequence is controlled by the position of the aircraft; the rest of the sequence can take place according to the theoretical flight plan of the aircraft, rather than according to the actual flight. The sequence can be reset periodically: start of a new sequence associated with a new overflight start of travel position.

In a more sophisticated version, the images calculated and displayed for the user take into account at any time the position variations and possibly even the attitude of the aircraft.

Other characteristics and advantages of the invention will appear on reading the detailed description which follows and which is given with reference to the appended drawings in which:

- Figure 1 shows the block diagram of the equipment envisaged according to the invention in the case of reconstructed images present in a database;

- Figure 2 shows a variant block diagram with the use of an image synthesis. The ultimate object of the invention is to avoid the presence of portholes and windshields for the aircraft, since it is a way of considerably simplifying the structure of aircraft and therefore reducing the cost thereof. Portholes indeed pose problems of mounting constraints, insulation, and pressurization. But it will be understood that it can also be implemented in the presence of portholes and windshields, the images provided being a complement to the direct external vision through the porthole; the advantage of this supplement exists on the one hand for the case where there is no external visibility (night, fog, clouds, etc.) and on the other hand to gradually accustom the passengers to journeys on airplanes without portholes, showing them that the landscape can be seen as well on a screen.

The important thing for passengers is the possibility of seeing the overflown landscape pass by, and of associating this possibility with a whole series of entertainment possibilities offered to them on the same individual (or possibly collective) screen in front of their seat, or side of the seat, or possibly even in place of a window to simulate a window.

The images are extracted from a database, as closely as possible with the instantaneous position of the aircraft. The computer which controls the display screen receives (either from another computer or from the same computer) an indication of geographical position, essentially in longitude and latitude, but possibly also in altitude. The indication of longitude and latitude is mainly used for addressing the database. The altitude information can be used especially when the plane is close to the ground, to allow the display of images taken from an angle of view which roughly corresponds to instantaneous reality; the altitude indication is then preferably supplied by a radiosonde.

From the position of the aircraft, the computer determines the data to be extracted from the base, whether it consists of an image or a sequence of overflown terrain corresponding to this position of the aircraft, or whether it is made up of terrain relief data from which a synthetic image of the terrain overflown can be reconstructed. This image is processed and displayed, then followed by other images so as to obtain a scrolling landscape view in correspondence with the variation in position of the aircraft. A treatment that can be used as example, assuming that the images come from vertical aerial views, oriented north / south, is a rotation of the stored image to give it an orientation that is related to the route followed by the plane. For example, if the screen is placed in front of the user in the direction of the longitudinal axis of the plane, we will rotate the stored image to display a landscape image whose vertical axis on the screen corresponds to the direction of the road to the ground of the aircraft in this landscape.

If the screen is intended to simulate a window placed laterally next to a passenger, the stored images will have to be side landscape views and not top views, and the solution then is

- either to use video sequences stored in the database, these sequences having been previously recorded in good visibility time by an aircraft carrying a side camera,

- either to generate a synthetic image which takes into account the orientation in which the passenger will see the screen, to make the synthesized image coincide with the image that the passenger would see if he looked through a window located at the place of the screen.

The successive images can all be taken from the database, each time renewing the address sent to the database, but it is also possible, to limit the number of addressing and extraction operations from the database. of data, for example provide that a fairly complete image is first extracted at a determined address from the database, that this image (possibly processed) is displayed, and that the following images are formed only by successive portions of the same image, shifting on the screen as the aircraft moves. In this case, the instantaneous position variation of the plane (or simply the integration of its instantaneous speed vector) is used to maintain the landscape point at the center of the screen (or at the bottom of the screen). plumb with which the plane is located. Before the image retrieved from the database leaves the screen, a new image extraction is made in the database and substituted for the previous one. The images stored in the database are preferably in mutual recovery to allow a smooth change. This solution is particularly suitable for showing a moving landscape in the form of a moving aerial photo. It will be understood that the stored images can comprise a landscape by day and a landscape by night and that one or the other is extracted according to the time of use, or that an appropriate processing (reduction of contrast and saturation of colors) is applied to a daytime image to give it the appearance of a nighttime image.

To move from one image to another image, an address derived from the position of the plane, known using the sensors on board the plane, in particular an inertial unit or GPS receivers, or a hybrid power plant mixing information from several sources. However, it is also possible to use, for more continuity when obtaining position information requires a non-negligible calculation time, instantaneous speed information of the airplane. In this case, if the successive data extracted from the database to generate successive images are obtained by incrementing addresses in the database, we can go from one image to the next by doing this incrementation not directly from successive positions of the airplane but from an integration of the north speed and the east speed of the airplane, however periodically readjusting the address from the calculated airplane position, so that there there is no significant discrepancy between the position of the aircraft and the displayed image. In one example, it is possible to adapt a speed of movement of successive video images as a function of the speed of the aircraft.

To give the user a correct visual reference, in relation to the instantaneous attitude of the plane, what is necessary either for his comfort if it is a passenger, or for the piloting aid s 'This is the crew, it is expected that the image displayed depends on the attitude data of the aircraft, especially with regard to the roll angles and the pitch. These data are accessible on the plane; they most often come from an inertial unit. The roll angle and pitch angle can be used to modify the appearance of the displayed image so that the user has the impression of seeing the landscape and the lines parallel to the horizon line tilt when the plane tilts, or it seems to see the lines parallel to the horizon line tighten and the horizon lower on the screen when the pitch angle increases. The use of the heading angle is not essential to modify the appearance of the displayed image, in any case with regard to the passengers, the direction of the ground speed vector being sufficient to determine the general orientation of the displayed image without there being any need to make a significant distinction between heading and road on the ground. With regard to passengers, this service will be added to the services already existing on the plane, and will use multi-purpose equipment residing on the plane (more and more individual screens, and possibly a screen simulating a side window, or even a screen that can be folded against the side wall to play the choice of the role of a conventional screen or the role of a virtual window). During most of the flight, the passenger will be able to see a reconstituted image of the ground overflown by the plane as if he were looking through a window; this reconstituted image can also be projected on a collective screen. If the plane flies over clouds, the passenger can still have a picture of the ground even if it is not the ground as it exists at the time of observation. He will be able to use zoom functions to see details, have associated explanations on the regions overflown, the sites and monuments to visit, etc., thus making a virtual visit of the route he is flying over.

In practice, it will be possible to use a broadcasting channel reserved for this function, other channels being intended for other distractions (films, etc.). The content broadcast on this channel may be linked to the seat occupied by the user (right seat, left seat), and it will of course depend on the route taken by the plane.

Among the image sources in the database, it will be possible to use, in the case of the reconstruction of an image by synthesis, the terrain databases commonly used for commercial navigation (specialized database for the avoidance of collisions with the ground). These databases contain all the definitions of relief of the terrestrial globe, and can be used to reconstruct a landscape, but obviously without the possibility of seeing real details such as roads of buildings, etc.

FIG. 1 represents the elements which can be used for the implementation of the invention in the case where the addressable database as a function of the position of the aircraft contains terrain images. The database is designated by the reference 10; it is embedded or not in the plane. If it is not on board, a high-speed radio communication means is provided between the aircraft and the database. A computer 12 can extract images or image sequences as a function of the position that it calculates. The position is calculated thanks to the signals supplied by one or more sensors 14 such as a GPS receiver. It can also be deduced, by integration, from information received from an inertial unit. The computer can perform the position calculation itself. The computer preferably also receives attitude information from the aircraft or calculates this attitude (pitch angle, roll angle, heading) as a function of information received from an attitude sensor 16. The attitude sensor may be constituted by the same inertial unit from which the position information is calculated.

The images or sequences of images extracted from the base at an address which is defined by the position of the aircraft are images resembling the terrain actually overflown or dominated by the aircraft at the location where it is. They are in principle processed by an image processing circuit 18 (which could be incorporated into the computer). This processing includes modifications such as rotation, change of scale, change of angle of view, perspective, etc. The processed images are provided on at least one user screen. This screen can take the form of a porthole and be positioned next to a passenger seat as a porthole would be, or even be positioned in front of the person. A man-machine interface 22 (keyboard, mouse, joystick, etc. and processing circuits) can be associated with the screen so that the user can dialogue with the computer to choose what he wants to display, image of terrain overflown , zoom on this terrain, other information on the terrain, or other distraction images.

FIG. 2 represents the elements which can be used for implementing the invention in the case where the database 10 does not directly contain terrain images but contains data allowing the reconstruction of a synthetic image of the terrain overflown . The database can essentially be a database analogous to that used in anti-collision systems with the ground: the relief of the terrain of the terrestrial globe or of defined geographic areas is stored in the database in a more or less meshed form. fine (for example finer near airports or in mountainous regions). This base can be addressed from the geographical position, and it stores the altitude of the terrain at each position defined by its longitude and latitude.

The content of the base therefore makes it possible to know the relief overflown and it can be used as input for a generator of computer-generated images 24. This generator of computer-generated images produces, under the control of the computer 12, an image relief from any desired angle of view, as is conventionally done in video games. This angle of view can be fixed for all the passengers on the plane or depending on the position of the passenger to whom the generated images are addressed, or even depending on the position of the display screen relative to the passenger if desired. truly simulate the presence of a porthole. The angle of view depends on the height of the plane above the ground (determined as the position of the plane from the position sensors 14). It also depends on the attitude of the plane, defined from the attitude sensor 16, so that the generated image tilts when the plane tilts in pitch and especially in roll, and of course l image turns when the aircraft course changes.

If you use a terrain database whose recorded altitudes are higher than the actual altitudes (to constitute a safety margin typically provided for anti-collision systems), it is preferable that this safety margin be removed for the needs of the landscape display.

Claims

1. Passenger transport aircraft, comprising means for extracting data from a prerecorded database (10), as a function of the position of the aircraft, and means for providing, from the database and as a function of the instantaneous position of the aircraft, realistic images representing the terrain overflown at this instant by the aircraft, and means (20) for displaying these images near a passenger seat.

2. Aircraft according to claim 1, characterized in that the images are displayed on a screen constituting a virtual window in a fuselage without window next to the passenger.

3. Aircraft according to claim 2, characterized in that the images are images corresponding to a landscape that the person could see if he looked through the window.

4. Aircraft according to one of claims 1 to 3, characterized in that the database contains prerecorded realistic images.

5. Aircraft according to claim 4, characterized in that the images are sequences of images photographed and recorded.

6. Aircraft according to claim 1, characterized in that it comprises means for processing (18) images to modify the images displayed, as a function of the attitude of the aircraft on heading, roll and pitch.

7. Aircraft according to one of claims 1 to 6, characterized in that it comprises means for magnifying the image, similar to a "zoom" of the camera, for displaying a more or less large portion of an image. stored. 8 aircraft according to claim 1 to 3, characterized in that the database contains terrain relief data of the area overflown and in that means (24) are provided for generating synthetic images representing a realistically the terrain overflown at a given instant, these images scrolling as the aircraft advances

9 aircraft according to one of claims 1 to 8, characterized in that the images scroll on the screen as a function of a position calculated by integration of a speed of the aircraft, the position being periodically readjusted to a supplied position by an on-board position sensor