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United States Patent Application |
20030184449
|
Kind Code
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A1
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Baumgartner, Klaus
;   et al.
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October 2, 2003
|
Docking system for airport terminals
Abstract
A docking system for airport terminals has a docking station subsystem and
a docking station for each gate. The docking station subsystem is
connected via a communication network to a central working position
(control device). The docking station subsystem includes an airfield
situation monitoring and processing segment ASMPS, at least one advisor
and guidance display segment AGDS, a data and status handler segment DSHS
having at least one video camera for each center line of the gate, and at
least one ground operation panel segment GOPS. The docking station
subsystem has an auxiliary subsystem connected to it, by which
information relating to aircraft models and the gate can be entered in
the docking station subsystem. A docking guidance system is connected to
other systems of an airport and includes a docking guidance subsystem for
each gate of the airport.
Inventors: |
Baumgartner, Klaus; (Stutensee, DE)
; Brennfleck, Martin; (Stutensee, DE)
; Konerth, John; (Munich, DE)
; Link, Norbert; (Karlsruhe, DE)
; Schnathmann, Detlef; (Kirchehrenbach, DE)
|
Correspondence Address:
|
SUGHRUE MION, PLLC
2100 Pennsylvania Avenue, NW
Washington
DC
20037-3213
US
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Assignee: |
SIEMENS AG
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Serial No.:
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392835 |
Series Code:
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10
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Filed:
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March 21, 2003 |
Current U.S. Class: |
340/958 |
Class at Publication: |
340/958 |
International Class: |
G08G 005/00 |
Foreign Application Data
Date | Code | Application Number |
Sep 22, 1997 | DE | 197 41 669.1 |
Claims
What is claimed is:
1. A docking guidance system for guiding an aircraft to a parking position
of an airport, comprising: a plurality of docking guidance subsystems,
wherein each docking guidance subsystem is associated with a respective
gate, at which the aircraft is to be guided to the parking position, each
docking guidance subsystem comprising: a control computer; at least one
detector connected to the control computer, wherein the detector is
configured to recognize a type of the aircraft approaching the gate and
to track a current position of the aircraft, and wherein the detector is
configured to supply information regarding the type and the current
position of the aircraft to the control computer; a display connected to
the control computer, wherein the display is configured to indicate the
type of the aircraft and to indicate directional information to a pilot
of the aircraft, in response to which the pilot moves the aircraft; and a
local operator panel to operate the docking guidance subsystem.
2. The docking guidance system of claim 1, wherein the detector comprises
a camera.
3. The docking guidance system of claim 2, wherein the camera comprises a
video camera.
4. The docking guidance system of claim 1, wherein the local operator
panel is configured to operate the docking guidance subsystem in response
to manual inputs of an operator.
5. The docking guidance system of claim 1, further comprising: a network
interconnecting the plurality of docking guidance subsystems; and a
central control unit connected to the network, wherein the central
control unit is configured to monitor and to control the docking guidance
system.
6. The docking guidance system of claim 1, wherein the docking guidance
system is configured to be protected by at least one password.
7. The docking guidance system of claim 1, wherein a plurality of operator
stations are connected to the network.
8. The docking guidance system of claim 1, wherein the docking guidance
system is configured to grant different authorizations to different users
of the docking guidance system.
9. The docking guidance system of claim 1, wherein the docking guidance
system is configured to log interactions of system operators with the
docking guidance system.
10. The docking guidance system of claim 1, wherein the docking guidance
system is configured to print error messages on at least one of an
operator screen or an alarm printer.
11. The docking guidance system of claim 1, wherein the docking guidance
system is configured to exchange status messages of a selected gate
between components of the docking guidance system.
12. The docking guidance system of claim 1, further comprising a control
room configured to display detector image pictures of at least part of
the aircraft to be guided to the parking position.
13. The docking guidance system of claim 1, wherein the docking guidance
system is configured to automatically start a docking process for the
aircraft to be guided to the parking position.
14. The docking guidance system of claim 1, wherein the docking guidance
system is configured to automatically test connections of the network to
the respective control computer of each docking guidance subsystem.
15. The docking guidance system of claim 1, further comprising a graphical
user interface to integrate monitoring and control functions into a
software of the docking guidance system for an additional docking
guidance subsystem that is associated with an additionally installed gate
of the airport.
16. The docking guidance system of claim 1, wherein the docking guidance
system is configured to execute test programs for troubleshooting errors
in the docking guidance system.
17. The docking guidance system of claim 1, wherein the docking guidance
system is configured to receive an "emergency stop" signal by an operator
of the docking guidance system.
18. The docking guidance system of claim 1, wherein the docking guidance
system is configured to receive manual commands by an operator of the
docking guidance system in order to start a docking process of the
aircraft to be guided to the parking position.
19. A docking guidance system for guiding an aircraft of one of plural
aircraft types to a parking position of an airport, comprising: a
plurality of docking guidance subsystems, wherein each docking guidance
subsystem is associated with a respective airport gate, each docking
guidance subsystem comprising: at least one detection unit connected to
the control computer and configured to produce signals for recognizing
the aircraft type of the aircraft and for tracking a current position of
the aircraft; a control computer receiving the signals and processing the
signals into output information; a display utilizing the output
information to display the aircraft type and directional information to a
pilot of the aircraft; and a local operator panel to operate the docking
guidance subsystem.
Description
[0001] This is a Divisional of U.S. application Ser. No. 09/755,096, filed
Jan. 8, 2001, which is a Continuation in Part of U.S. application Ser.
No. 09/533,245 filed Mar. 22, 2000, which, in turn, is a Continuation of
International Application PCT/DE98/02822, with an international filing
date of Sep. 22, 1998. The disclosures of these three prior Applications
are incorporated into this application by reference.
FIELD OF AND BACKGROUND OF THE INVENTION
[0002] The invention relates to new and useful improvements in a docking
system for airport terminals. More particularly, the invention relates to
a docking system for airport terminals having a positioning apparatus by
which an aircraft can be guided to a parking position appropriate for its
type, a video device by which the aircraft can be detected as it
approaches the airport terminal, and an evaluation unit by which it is
possible to evaluate data which are supplied to the evaluation unit by
the video device and which relate to the form and the movement of the
aircraft.
[0003] German Patent DE 40 09 668 A1 discloses a procedure in which a
video camera is used to detect a two-dimensional image, which is passed
to an evaluation unit.
OBJECTS OF THE INVENTION
[0004] An object of the invention is to further develop the known docking
system. A further object is to develop the known system in such a manner
that it can be used even in adverse environmental and weather conditions
with an extremely high operational reliability, sufficient for the
operation of airports.
SUMMARY OF THE INVENTION
[0005] These and other objects are achieved according to one formulation
of the invention in that a template set for each different type of
aircraft is stored in the evaluation unit, which set contains at least
three, preferably five, specific templates for all types of aircraft or
outline sections of the relevant type, and in that the at least three,
preferably five, specific outline sections of the aircraft which is
approaching the airport terminal can be determined and compared with the
stored template sets, in the evaluation unit, from the input signals from
the video device.
[0006] According to another aspect of the invention, a docking system is
provided for airport terminals, which has a comparatively low level of
installation complexity and, furthermore, allows the airport terminals to
be operated in a safe and, for the most part, automated fashion. Precise
detection of the type of aircraft approaching the airport terminal is
ensured even if the entire contour of the approaching aircraft cannot be
detected by the video device, for example because there are obstructions
in the parking area or ramp area of the airport terminal.
[0007] A monochrome camera has been found to be a particularly suitable
video device for implementing the docking system according to the
invention and its positioning apparatus.
[0008] The objective focal lengths of the video device should
advantageously be 16 or 25 mm.
[0009] Adequate detection of the aircraft approaching the airport terminal
is ensured if the video device is arranged such that it is approximately
aligned with the center line of the airport gate, preferably at a height
of approximately 9 m.
[0010] The type of aircraft approaching the airport terminal can be
detected with a comparatively low level of complexity if a sequence of
gray tone images produced by the monochrome camera can be read to the
evaluation unit, the individual gray tone images in the sequence can be
spatially filtered in order to extract gray tone edges, the sequence of
gray tone images can be filtered in the time domain in order to produce
moving images, and a mask can be produced from the moving images defining
areas for subsequent segmentation.
[0011] The evaluation unit should expediently have a Sobel filter for
spatial filtering of the gray tone images, and for filtering the gray
tone images in the time domain.
[0012] Two engines, the windshield and two landing gear legs have been
found to be outline sections which are particularly specific to the
aircraft contour of each type. These five specific outline sections or
templates expediently form a template set. This template set is defined
for the respective aircraft type and stored in the evaluation unit.
[0013] Trajectories of the templates or specific outline sections of the
aircraft contour can be used as a basis to determine the present position
of the aircraft as it approaches the airport terminal.
[0014] When the docking system according to the invention, in particular
its positioning apparatus, is implemented and installed completely, it is
possible to allow all the processes required for docking of the aircraft,
in particular the docking of the bridge to the aircraft, to be carried
out automatically. In this case, it is possible for the video device to
have only one video camera.
[0015] In a particularly advantageous manner, the pixel processing
described above as well as the detection of the type of aircraft
approaching the gate of the airport terminal can be used for a docking
system for airport terminals wherein each gate has a docking station
subsystem. The docking station subsystem is connected via a communication
network to a central control device. In addition, it has an airfield
situation monitoring and processing segment, at least one advisor and
guidance display segment, a data and status handler segment having at
least one video camera for each center line of the gate, and at least one
gate operator panel segment. An auxiliary subsystem is connected to the
docking station subsystem, by which information relating to aircraft
models and the gate can be entered into the docking station subsystem.
[0016] The docking station subsystem expediently has an advisor and
guidance display segment for each center line of its gate.
[0017] A particularly advantageous embodiment of this advisor and guidance
display segment is achieved if a microprocessor is provided which
controls the display elements and converts display commands into
indications of the display elements.
[0018] An embodiment of the docking station subsystem according to the
invention and of the docking system according to the invention which is
less complex in terms of equipment and design is achieved if the data and
status handler segment of the docking station subsystem runs on the same
hardware as the airfield situation monitoring and processing segment.
Also, in this embodiment, the communication between the docking station
subsystem and the central control device takes place via the
communication network, and the processes within the docking station
subsystem are coordinated by the data and status handler segment.
[0019] In a further development of the docking system according to the
invention, the data and status handler segment and the airfield situation
monitoring and processing segment of the docking station subsystem may be
arranged in one housing.
[0020] Expediently, the data and status handler segment and the airfield
situation monitoring and processing segment may run on a hardware basis
comprising a PC motherboard and video signal processing equipment.
[0021] If the design of the docking station subsystem for the docking
system according to the invention provides for the data and status
handler segment and the airfield situation monitoring and processing
segment to be arranged outside the actual gate, it is possible to
additionally arrange the advisor and guidance display segment in the
housing common to the two components mentioned above.
[0022] In a further specific embodiment of the docking system according to
the invention, the docking station subsystem is designed such that it
allows advisor and guidance displays to be transmitted to a screen in the
cockpit of an aircraft which is approaching the gate. This mode of
operation may be used instead of operating the advisor and guidance
display segment, or may be provided in addition to operating this advisor
and guidance display segment.
[0023] It is also possible to arrange the airfield situation monitoring
and processing segment in a housing with the video camera.
[0024] For transmission of data between the airfield situation monitoring
and processing segment and the data and status handler segment of the
docking station subsystem, it is expedient for the airfield situation
monitoring and processing segment to have an associated digital signal
processor. In the digital signal processor, the originally analog video
signals are converted into digital signals before they are passed to the
input line to the data and status handler segment.
[0025] The auxiliary subsystem which is associated with the docking
station subsystem of the docking system according to the invention
preferably has an aircraft model output, a gate installation planner, a
calibration unit and a validation and diagnosis tool. The communication
network of the docking system according to the invention is
advantageously in the form of a high-speed network using an asynchronous
transmission mode, by which originally digital signals and originally
analog signals converted into digital signals can be transmitted, e.g.
video signals.
[0026] The ATM high-speed network may advantageously have at least one
network adapter in the form of a SICAN-ATMax 155-PM2.
[0027] The docking station subsystem of the docking system according to
the invention is systematically and expediently broken down into a ground
area monitoring and processing segment, a gate area control segment, a
gate schedule segment and a gate data handler segment.
[0028] The ground area monitoring and processing segment advantageously
has an airfield monitor and an airfield situation processor, which is
connected by means of an interface to the gate schedule segment.
[0029] The gate area control segment of the docking station subsystem of
the docking system according to the invention has airfield ground
lighting, an advisor and guidance display, a ground operator panel, a
luxometer and a gate area processor. The gate area processor runs on a PC
platform to which the airfield ground lighting, the advisor and guidance
display, the ground operation panel and the luxometer are connected. In
addition, the gate area processor is connected by an interface to the
gate schedule segment.
[0030] The gate data handler segment should advantageously have a
calibration support and static data handler, which run on a PC platform
and are connected in each case by means of one interface to the gate
schedule segment.
[0031] The gate schedule segment of the docking station subsystem of the
docking system according to the invention has gate management and a
watchdog.
[0032] In accordance with another formulation of the present invention, a
docking guidance system includes a plurality of stand alone systems,
which are associated with respective gates of an airport. These stand
alone systems are interconnected by a network. If an aircraft approaches
a particular gate, at which it is to be docked, the respective stand
alone system guides the aircraft to its proper final parking position at
the particular gate. To this end, the respective stand alone system
receives guidance data regarding the guidance of the aircraft, e.g., data
from a video camera, which attempts to recognize the aircraft type and
which monitors the current position and movement of the aircraft.
[0033] In the case of large and mid-sized airports, these guidance data
are forwarded to a central working station, which monitors and controls
the overall operation of the docking guidance system. In addition, the
central control device exchanges data with external airport systems, such
as a surface movement guidance and control system (SMGCS) and a central
monitoring system (CMS). In the case of large airports, which have many
terminals, the central control device also exchanges data with operator
stations at each terminal. In the case of mid-sized airports, only one
operator station is provided, which is located at the central control
device, for example. By processing all these data from the different
systems of an airport, the central control device is capable of
performing its central monitoring and control function for the docket
guidance system.
[0034] In the case of small airports, it is possible to dispense with an
operator station and a central control device. Instead, all the stand
alone systems communicate directly with each other over the network
connecting the stand alone systems. In this way, a docking process of an
aircraft, which is in progress at a particular gate, can be monitored
and, if necessary, influenced by an operator present at another gate, for
example.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] The invention and further advantageous embodiments of the invention
according to the features of the dependent-claims are explained in more
detail below with the aid of diagrammatic, exemplary embodiments in the
drawings, in which:
[0036] FIG. 1 shows a basic illustration of the docking system according
to the invention, and its integration in an airport network;
[0037] FIG. 2 shows a basic illustration of an aircraft approaching a gate
of an airport terminal;
[0038] FIG. 3 shows a basic illustration of the method for finding an
aircraft outline of an aircraft approaching a gate;
[0039] FIG. 4 shows a sequence for searching for the aircraft outline of
the aircraft approaching the gate, and for initiation of tracking and
following the aircraft found;
[0040] FIG. 5 shows a data flowchart of the docking system according to
the invention and its integration in the communication network of an
airport;
[0041] FIG. 6 shows a basic illustration of the major components of the
docking system according to the invention;
[0042] FIG. 7 shows a first embodiment of a docking station subsystem of
the docking system according to the invention;
[0043] FIG. 8 shows a second embodiment of the docking station subsystem
of the docking system according to the invention;
[0044] FIG. 9 shows a third embodiment of the docking station subsystem of
the docking system according to the invention;
[0045] FIG. 10 shows a systematic segment structure of the docking system
according to the invention;
[0046] FIG. 11 shows a ground area monitoring and processing segment GAMPS
of the docking station subsystem illustrated in FIG. 10;
[0047] FIG. 12 shows a gate area control segment GACS of the docking
station subsystem illustrated in FIG. 10;
[0048] FIG. 13 shows a gate data handler segment GDHS of the docking
station subsystem illustrated in FIG. 10;
[0049] FIG. 14 shows a gate schedule segment GSS of the docking station
subsystem illustrated in FIG. 10;
[0050] FIG. 15 shows a schematic overview of an arrangement of the docking
guidance system according to the present invention in relation to other
systems of an airport;
[0051] FIG. 16 shows a software structure of the docking guidance system
according to the present invention configured for large airports having
multiple terminals;
[0052] FIG. 17 shows a software structure of the docking guidance system
according to the present invention configured for mid-sized airports;
[0053] FIG. 18 shows a software structure of the docking guidance system
according to the present invention configured for small airports;
[0054] FIG. 19 shows a preferred architecture of a central control device
of the docking guidance system according to the present invention;
[0055] FIG. 20 shows an overview of a preferred embodiment of a Siemens
Docking Guidance System (SIDOGS);
[0056] FIG. 21 shows an exemplary screen display of a central control
device of the SIDOGS of FIG. 20; and
[0057] FIG. 22 represents a preferred calibration system for calibrating
the angular field and/or position of a TV camera or video camera of the
docking guidance system according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0058] An airport terminal 2 integrated in an airport network 1 as shown
in principle in FIG. 1 is equipped with a docking system by which, via a
bridge, a connection to the interior of an aircraft 3 can be produced
(FIG. 2).
[0059] In order to position the aircraft 3 correctly for the docking
process at the airport terminal 2, all the gates 4 of the airport
terminal 2 each have an associated positioning apparatus, by which the
aircraft 3 that is intended to be docked can be guided to a stopping or
parking position 5 appropriate to its type.
[0060] To this end, the positioning apparatus has a video device 6, which,
in a preferred embodiment, is in the form of a monochrome camera, by
which the aircraft 3 can be detected as it approaches the gate 4 of the
airport terminal 2. The positioning apparatus additionally includes an
evaluation unit 7 by which data supplied to it from the video device 6
and relating to the form and movement of the aircraft 3 can be evaluated.
Finally, the positioning apparatus includes a display 8 by which a pilot
of the aircraft 3 can be provided with information required to move the
aircraft 3 to the intended parking position 5.
[0061] Since the parking position 5 differs depending on the type of
approaching aircraft 3, the positioning apparatus first of all has to
determine the type of aircraft 3 that is approaching. To do this, the
video device 6 is used to produce gray tone images onto which the
aircraft 3 that is approaching the gate 4 is mapped. By means of the
video device 6, a sequence of gray tone images, showing different
positions of the aircraft 3 that is approaching the gate 4, is read into
the evaluation unit. Evaluation of this sequence of gray tone images
within the evaluation unit allows moving edges to be detected, which
correspond to the outline of the aircraft 3 that is approaching the gate
4. This is done firstly by using spatial filtering, by which the spatial
edges in the individual gray tone images are found. Filtering in the time
domain is used to extract edges which move over time, so that it is
possible to distinguish between moving and stationary objects. This makes
it easier to determine an aircraft outline from the gray tone images.
Each type of aircraft has a specific aircraft outline which, for its
part, has specific outline sections or templates. For selecting suitable
templates, a template set may be formed, to provide examples of the
respective types of aircraft. This template set may contain three, or
preferably five, individual templates.
[0062] A template set is stored within the evaluation unit 7 for each type
of aircraft. The aircraft contour determined for the aircraft 3
approaching the gate 4, or the template set resulting from this, is now
compared with the template sets stored within the evaluation unit. As the
result of this comparison operation, the type of aircraft 3 approaching
the gate 4 of the airport terminal 2 is determined. This type has a
specific associated parking position 5. Details are now indicated on the
display 8 to allow the aircraft captain or pilot to move his aircraft 3
to this parking position 5.
[0063] The aim of the following text is to describe in detail how edge
operators in spatial space are used to extract the stationary gray tone
edges from the gray shade images, in order to obtain the aircraft
contour.
[0064] A Sobel operator can advantageously be used for this purpose, which
is not derived from a mathematically closed form. This Sobel operator has
the following forms: 1 Form 1 : - 1 , - 2 ,
- 1 0 , 0 , 0 1 , 2 , 1 Form 2 :
- 1 , 0 , 1 - 2 , 0 , 2 - 1 , 0 ,
1
[0065] Form 1 extracts edges located horizontally in the gray tone image,
and form 2 extracts edges located vertically in the gray tone image. This
is done by means of a weighted first derivative in the respective
coordinate direction under consideration. Both Sobel operators have been
applied to the gray tone image, and their results have been linked
alternately by pixels: 2 b i , j = b 1 , i , j 2 + b 2 , i
, j 2 2 .
[0066] Moving edges can be extracted not only by considering a gray tone
image, but also by considering a time sequence of gray tone images. The
filter cores therefore have to have a time dimension. Not only filter
cores which have only one time dimension, but also filter cores which
have time and space dimensions were investigated.
[0067] A Laplace filter, a Mexican hat operator or a HildrethMarr operator
and a Sobel operator have been found to be particularly expedient as
filter cores. In the latter case, the concept of a two-dimensional edge
filter which operates with a weighted first derivative was expanded to
three dimensions. This results in the following operator core in three
dimensions of size 3.times.3.times.3: 3 - 1 , - 1 , - 1
- 1 , - 8 , - 1 - 1 , - 1 , - 1 t
= 0 0 , 0 , 0 0 , 0 , 0 0 ,
0 , 0 t = 1 1 , 1 , 1 1 , 8 , 1 1 ,
1 , 1 t = 2
[0068] Filtering using the Sobel filter produced the best results for both
the spatial and time edges.
[0069] FIG. 3 shows the fundamental program sequence for determining the
aircraft contour.
[0070] A gray tone image sequence which has been recorded by the video
device 6 is passed via a video input to the evaluation unit 7. There,
this gray tone image sequence is subjected to spatial filtering, by which
spatial edge filtering of the respective gray tone image is carried out.
The result of this spatial edge filtering represents the magnitude of a
Sobel operator in the x direction and y direction, and is stored. This
spatial edge filtering is used to extract gray tone edges, which are
available as an intermediate result.
[0071] Time-domain edge filtering of successive grayshade images is
carried out in the time-domain filtering which follows the spatial
filtering. The result of this time-domain edge filtering represents the
magnitude of a Sobel operator expanded by the time direction, and is
stored. An intermediate result is once again available as the result of
the time-domain edge filtering.
[0072] The thresholding which follows the time-domain filtering is used to
produce a binary image from the gray tone image. The digitization
threshold is defined by the variable threshold value. For gray shades
below this threshold value, a low value is entered in the output binary
image, and a high value is entered in it for values which are equal to or
exceed the threshold value. The thresholding provides a further
intermediate result.
[0073] The thresholding is followed by the functional stage of dilatation,
in which the binary image produced in the course of thresholding is
subjected to dilatation with a size of one pixel, that is to say all
those areas which have a gray level greater than zero are enlarged by one
pixel at their boundaries. The functional stage of dilatation provides an
intermediate result, which corresponds to the mask or outline contour of
the aircraft 3 approaching the airport terminal 2 or its gate 4.
[0074] The aircraft contour is positioned by the method whose principle is
illustrated in FIG. 4. In this case, it is assumed that the aircraft 3
that is approaching the gate 4 of the airport terminal 2 will turn in at
the latest at a predetermined minimum distance from the parking position
in the region of the gate 4. It is also assumed that the aircraft captain
or pilot will in the process orient himself approximately on the center
line of this gate 4. To do this, a catchment position is defined on this
center line. A search area is defined around this catchment position, in
which area the features that define the aircraft contour or the aircraft
type are searched for. The defined size of this catchment area depends on
the permissible lateral error for the aircraft 3 that is approaching the
gate 4.
[0075] The individual templates which form the template set for an
aircraft type must be chosen such that they are not invariant with
respect to displacements. Furthermore, they are chosen to have a high
contrast in the sequence of gray tone images. In addition, the selected
features or templates must be highly tolerant to external influences,
such as lighting and weather. The following features and individual
templates have therefore been chosen for the aircraft types so far
included in the form of template sets: The two engines, the windshield
and the two landing gear legs. An individual template set is produced for
each aircraft type by these individual templates.
[0076] The aircraft 3 is now looked for around the position defined in the
ramp area. Since the aircraft 3 is a rigid body, a fixed arrangement of
the chosen features can be predetermined. These features may appear
distorted only due to the orientation of the aircraft 3 with respect to
the video device 6. For this reason, it is desirable to find an optimum
or elastic grid. In order to achieve this aim, the system looks for the
maximum cross-covariance value in a defined search area around each
template. The sum of all the cross-covariance values is a measure of
whether the aircraft type has been found. By using an elastic grid, it is
also possible in the process of "position determination" that follows
later to determine the orientation of the aircraft 3. This orientation
information may in turn be used for better tracking.
[0077] The search is carried out in the spatial Sobel-filtered image,
which reproduces the gray tone edges and is thus considerably less
sensitive to lighting influences than the underlying edge image. In
comparison to other operators, the spatial Sobel-filtered image has the
best edge contrast with the best noise suppression.
[0078] The position of a template is determined by shifting the template
over the edge image until the similarity measure assumes a maximum. The
cross-covariance is used as the similarity measure for this purpose,
since this forms a better maximum/environment contrast than
cross-correlation. It also has a better maximum-to-noise ratio compared
to Euclidean distance.
[0079] The data flowchart illustrated in FIG. 5 shows how individual
functional components of the docking system according to the invention
communicate with other functional components of this system and with
further functional components of an airport control system outside the
actual docking system.
[0080] FIG. 5 is subdivided into a first phase and a second phase, as is
shown by the dotted boundary lines in FIG. 5. The lower part, which
describes the first phase, of FIG. 5 is the major element for the docking
system according to the invention, since the major functional elements of
the docking system itself are illustrated there. In contrast, the upper
part of FIG. 5 shows a central control device (central working position
CWP) of an airport, which is connected to the docking system according to
the invention. The central control device (CWP), for its part, is related
to the airport control system via a central monitoring and surveillance
system interface (CMSI) and a user defined interface (UDI).
[0081] In the illustration in FIG. 5, the docking system according to the
invention is broken down into four functional units. First of all, a
functional unit comprising a docking status/data handler (DSH) and
calibration support (CS) is provided there. This functional unit receives
central control signals, database updates and monitoring and surveillance
data relating to the respective gate (gate i CMS data) from the CWP. From
this functional unit DSH, CS the CWP receives status details relating to
the respective gate (gate i statuses), live video signals from this gate
(gate i live video) and central monitoring and surveillance data relating
to this gate (gate i CMS data).
[0082] The functional unit DSH, CS has a calibration input and an output
to a calibration display. Furthermore, the functional unit DSH, CS
outputs recorded video sequences as well as control signals for the
airfield ground lighting (AGL control). The DSH operates together with a
further functional unit, namely the airfield situation processor (ASP) on
a PC based system. The functional unit ASP receives from the DSH of the
functional unit DSH, CS control signals for the ASP (ASP control),
initialization data and black-and-white video data (B & W Video Data).
The DSH of the functional unit DSH, CS receives from the functional unit
ASP tracking results as well as ASP check results.
[0083] Furthermore, data relating to the gate configuration are entered in
the functional unit DSH, CS while, in contrast, said functional unit
outputs data relating to the docking process (docking log data).
[0084] As a further functional unit, the docking system according to the
invention has a ground operator panel (GOP) from which transfer data are
entered in the functional unit DSH, CS, and which receives transfer data
from the functional unit DSH, CS. Furthermore, operation commands and
test commands are entered in the GOP, while the GOP outputs the docking
status, test results and an aircraft type table (a/c type table).
[0085] An advisor and guidance display (AGD) is provided as a further
functional unit of the docking system according to the invention, which
enters self test results in the functional unit DSH, CS and receives from
this functional unit data to produce the characters for the display
information (display information character generation data). The AGD
outputs guidance and verification signals and test patterns. A preferred
embodiment of a display of the AGD is described in more detail in
connection with FIG. 20.
[0086] As can be seen from FIG. 6, the docking system DGS according to the
invention in principle has three partial operating systems, namely a
docking station subsystem (DSS), a central controller working position
subsystem (CWPS) and a communication network subsystem (CNWS). The DSS
contains all those system segments which are arranged at the gates. The
CWPS comprises a display and control system which is based on a
workstation and is provided in a central control room at the airport. The
CNWS is the network which connects these two subsystems to one another,
in order to transmit data between these subsystems.
[0087] An auxiliary subsystem (AuxS) associated with the DSS contains a
number of auxiliary functions, for example the production of new aircraft
models, the gate configuration and maintenance.
[0088] The DSS is connected on the one hand to the airfield situation, and
on the other hand to the maintainer, calibrator, bridge personnel, ground
personnel, (co-)pilot and the AGL. The gate specifier, the aircraft model
specifier (a/c model specifier), the installation personnel and the
research department can be connected to the DSS via the AuxS.
[0089] The CWPS of the docking system according to the invention is on the
one hand connected to the administrator, the maintainer, the supervisor
and the controller. On the other hand, it is connected to the central
monitoring and surveillance system, the airport database, user defined
gate systems, the AGL, time reference systems, and a surface movement
guidance and control system (SMGCS).
[0090] The DSS serves two or more central lines or center lines for the
gate. Two center lines or central lines can be served by one DSS,
provided the two are mutually dependent and/or provided the one cannot be
used while the other is in use.
[0091] As can be seen from FIGS. 7, 8 and 9, the DSS has four different
segments: the airfield situation monitoring and processing segment
(ASMPS); the advisor and guidance display segment (AGDS); if there are
two mutually dependent central or center lines, a second AGDS may be
required, depending on the configuration and/or arrangement of the
central or center lines at the gate. The AGDS contains an integrated
microprocessor, which controls the display elements and converts display
commands into displays; the data and status handler segment (DSHS) with
one or two video cameras for each central line or center line; the number
of video cameras for each central line or center line depends on the
aircraft types which may dock at the respective gate; the DSHS runs on
the same hardware as the ASMPS. It provides the communication between the
DSS and the CWPS via the CNWS, and coordinates the processes within the
DSS.
[0092] The gate operator panel segment (GOPS) is a microprocessor-based
system having a small keyboard or keypad and a liquid crystal display
LCD, which transmits only the input data to the DSHS and outputs the data
from the DSHS to the LCD.
[0093] Three different embodiments of the docking station subsystem DSS
differ essentially by the arrangement of the ASMPS and DSHS.
[0094] A first embodiment, illustrated in FIG. 7, provides for the ASMPS
and the DSHS to be arranged in the same housing together with and at the
same location as the AGDS, as can be seen from the double line
surrounding said segments in FIG. 7.
[0095] The ASMPS and the DSHS run on a PC motherboard and on the video
processing equipment which comprises, for example, a so-called frame
grabber; interface elements are provided to the GOPS 1 to 4, to the AGDS
1 and 2, to the auxiliary interface and to the CNWS, but without any
mechanically operating parts.
[0096] The auxiliary interface can be used, for example, to calibrate the
video camera 9 and the further video camera 10, or to test the DSS. If
the DSS is operated on its own, the auxiliary interface may be used to
input the gate configuration and the aircraft database, or to output
recorded video sequences. The AGDS has a simple microprocessor and three,
or possibly four, LED arrays. The simple microprocessor provides the
communication with the DSHS and controls the LED arrays.
[0097] RS 232, RS 422 and RS 485 type interfaces, or interfaces based on
optical links, may be used as the interface between the DSHS and the GOPS
1 to 4 or the AGDS 2. An RS 232 type interface may be used as the
interface between the DSHS and the AGDS.
[0098] The second version or embodiment of the docking station subsystem
illustrated in FIG. 8 has a common housing just for the ASMPS and the
DSHS, as can be seen from the double line which surrounds the two
segments in FIG. 8. These two segments are arranged separately from the
other equipment in an equipment room. The AGDS is, furthermore, arranged
in the outer gate area, of course. It can be seen from this that the
interfaces between these segments differ from those in the first
embodiment. The interface between the AGDS and the DSHS now corresponds
to the other RS 232, RS 422 etc. type interfaces.
[0099] A video monitor 11 and a keyboard or keypad 12 are now provided
instead of the auxiliary interface, and can carry out the functions of
the auxiliary interface provided in the first embodiment.
[0100] In the third embodiment of the DSS illustrated in FIG. 9, the ASMPS
is accommodated inside a housing 13 or 14, respectively, of the video
camera 9 or 10, respectively. The required software runs on a digital
signal processor, which transmits the aircraft position digitally to the
DSHS. The DSHS may be in the form of a PC or microprocessor board of
relatively low performance. In principle, it is also possible to
accommodate the DSHS in a housing with the AGDS or the AGDS 2.
[0101] The major difference between the described embodiments is the
arrangement of the hardware that forms the ASMPS and the DSHS. There are
more minor differences in the auxiliary interface and in the interface
between the AGDS and the DSHS.
[0102] The first embodiment requires the capability for the hardware that
forms the ASMPS and the DSHS to operate in outdoor environmental
conditions.
[0103] The advantage of the first embodiment is that it involves only a
minimum level of installation complexity. The interface between the AGDS
and the DSHS has a simple configuration. On the one hand, the reliability
may be greater since less installation complexity and no mechanically
operating equipment parts are required. On the other hand, operation is
required in outdoor environmental conditions; this reduces the
reliability, even if cooling or heating measures are provided.
[0104] The auxiliary subsystem which is used as the auxiliary system AuxS
is required to start and to maintain the system during system
installation and during system maintenance. It comprises an aircraft
model editor (AME), a gate installation planner (GIP), a calibration tool
(CT), a validation and diagnosis tool (VDT) and a maintainer support
tool.
[0105] The AME may be installed on a separate PC. In the second embodiment
of the DSS, the aircraft model may be transmitted by means of a floppy
disk to the operating system, while in the first and third embodiments it
may be transmitted by means of a laptop PC and the auxiliary interface.
If all the isolated systems are connected by a network, such data can be
integrated via the CWPS.
[0106] The GIP produces a hard-copy installation plan and the gate
configuration on a disk. The gate configuration may be entered in the
operating system in the same way as the aircraft models.
[0107] The VDT may run on a separate PC. The data may be entered in this
PC via the auxiliary interface if the system is isolated, or may be input
via the CNWS and CWPS. In the second embodiment of the DSS, the VDT may
also run on the isolated system.
[0108] The CT supports the calibration process with a graphics display.
The calibrator can carry out the calibration interactively. The
calculated calibration data remain in the DSS.
[0109] The CNWS may be in the form of an ATM network, in which at least
one switching unit may be provided. A UNI 3.1 or UNI 4.0 should be used
for signaling. 155 Mbit/s or 25 Mbit/s adapters may be used, depending on
the bandwidth requirements. The distances which can be achieved depend on
the transport medium: monomode fibers for long distances, multimode
fibers for medium distances, or twisted double wires for short distances.
[0110] The advantages of such a high-speed ATM network are that long
distances are possible, no electromagnetic interference occurs, DC
isolation is provided, a guaranteed bandwidth is ensured between two data
end points, and a guaranteed delay is ensured between two data end
points.
[0111] The CWPS may run on a PC system using the Windows NT operating
system. Furthermore, a Video-HW-ProVisionBusiness and an ATMax 155-PM2
ATM adapter from SICAN GmbH are preferably used as hardware components.
[0112] In the DSS illustration chosen in FIG. 10, the subsystem level
illustrated in FIGS. 7 to 9 has been omitted; based on the illustration
in FIG. 10, the DSS has the following segments: a ground area monitoring
and processing segment (GAMPS), a gate area control segment (GACS); a
gate schedule segment (GSS), a gate data handler segment (GDHS), a
communication network segment (CNWS), a central working position segment
(CWPS); and an auxiliary functionalities segment (AuxS).
[0113] The GAMPS illustrated in FIG. 11 has airfield monitoring (AM) and
an airfield situation processor (ASP). This supports the following
functions: frame grabbing, calculation of the display information from
the position data which is provided by the ASMPS, processing of the
airfield situation, calculation of real-world positions, and video
recordings.
[0114] The GAMPS assists the GSS in investigating the airfield situation
during the docking sequence. It provides self-test and calibration
information as well as video images for calibration of the GSS. In
addition, the GAMPS supplies the AuxS with recorded video sequences.
[0115] The GACS comprises the airfield ground lighting (AGL), the advisor
and guidance display (AGD), the gate operator panel (GOP), the luxometer
(LM) and the gate area processor (GAP). The GAP runs on a PC platform to
which the AGL, the AGD, the GOP and the LM are connected.
[0116] The GACS supports the following functions: Measurement of the light
intensity in the area of the gate; Switching for the AGL; Display of
guidance and verification details for the aircraft pilot and display of
test patterns for the ground personnel, with one or two AGDs being
provided; Input of operating and test commands by the ground personnel
via one to four GOPs, output of test results and docking status to the
ground personnel via the GOP, self-testing of all parts of this segment,
and communication and data interchange with the GSS.
[0117] The GACS has to measure the light intensity in the gate area, and
convert it into dark or light information. The GACS converts the GOP
inputs and forwards them to the GSS. On the other hand, the GACS receives
commands from the GSS, interprets them, and passes the corresponding
display information to the AGD and to the GOP, switches the AGL on or
off, and tests the communication lines to the AGD and GOP.
[0118] The GDHS illustrated in FIG. 13 has a calibration support (CS) and
a static data handler (SDH), both of which run on a PC platform.
[0119] The main tasks of the GDHS are management of the calibration
process, management of updates of the gate configuration, and storage of
the gate configuration and of the aircraft types.
[0120] During the set-up phase in isolated operation, it reads the gate
configuration data from a file which has previously been produced by the
GIP. In network operation, it reads the data via the GSS from the
CNWS/CWPS, and stores this data internally.
[0121] The GSS illustrated in FIG. 14 comprises the gate manager (GM) and
the watchdog (WD).
[0122] The main tasks of the GSS are to control the action sequence within
the signal, to supply the GAMPS with calibration and aircraft data, to
produce time stamps and time inhibits, to trigger the watchdog and to
interchange data with surrounding segments.
[0123] In isolated operation, the GSS provides the information input and
output for the GOP via the GACS. In network operation, the interface to
the CNWS/CWPS is also controlled. The GSS transmits compressed live video
images and status information to the CNWS/CWPS. Alternatively, the
docking sequences may be carried out via the CWPS. In this context, the
information input and output for the GOP is interchanged via the GACS and
via the CNWS with the CWPS.
[0124] During the set-up phase, system control is passed to the GDHS. In
network operation, the GSS supplies the GDHS with the transmission of
configuration data via the CNWS/CWPS.
[0125] During the calibration process, the GSS passes system control to
the GDHS. It transmits video images from the GAMPS to the GDHS. It uses
the GAMPS to verify calibration data. When the gate configuration is
being updated, the docking mechanism is deactivated.
[0126] Upon completion of a docking sequence, the live video signals for
the last docking sequence can be repeated either by the PC monitor, the
keyboard or keypad and the mouse in isolated operation, or via the
network on the CWPS in network operation. It is impossible to initiate a
docking sequence while a recorded video sequence is being viewed.
[0127] Maintenance tests may be initiated through the GOPS by the ground
personnel or, controlled by the CNWS/CWPS, through the GSS.
[0128] The GSS triggers the watchdog periodically; otherwise, the watchdog
resets the PC.
[0129] The CNWS provides the communication between the CWPS and the GSS at
the various gates, and vice versa. It transmits commands, data and
compressed video images; the latter are transmitted only when
specifically requested.
[0130] The main tasks of the CWPS are: Display of the planned and actual
gate occupancy, display of the status of a docking process for the
control center personnel, inputting gate configurations for a specific
gate, inputting new aircraft models, data interchange with surrounding
systems, for example maintenance, flightplan data, or planned gate
occupancies.
[0131] The planned and the actual occupancy of gates may be displayed
graphically at any time. The global picture can be split up into a number
of smaller areas. One panel with all the gates occupied and the
associated calling symbols is shown. The control center personnel can
occupy a specific gate manually. Information about a specific gate and
live video transmission may be selected. The planned data is shown in a
specific block diagram. The planned occupancy may be changed or modified
as required. The CWPS ensures that any change does not contravene gate
restrictions, for example by aircraft types being assigned to a gate
which is unsuitable for such aircraft types.
[0132] The main functionalities of the AuxS are to assist the
specification of a gate, that is to say the coordinates of the central
line or center line and the stopping position, aircraft types permissible
for that gate, the specification of new aircraft models, and displaying
the repetition of recorded docking sequences for evaluation.
[0133] These functionalities may be carried out at a separate workstation.
The data transmission from and to these functions is carried out by means
of a disk or some other medium, depending on the required capacity.
[0134] FIG. 15 shows a schematic overview of how a docking guidance system
according to the present invention is arranged in relation to other
systems of an airport, e.g., a time reference system, an airfield ground
lighting system, a user defined gate system, an airport data base, and a
central monitoring system.
[0135] The time reference system provides the docking guidance system with
date and time information, as indicated by the arrow from the time
reference system to the docking guidance system.
[0136] As indicated by the arrow from the airfield ground lighting system
to the docking guidance system, the airfield ground lighting system sends
signals regarding the status of lighting equipment for the airfield
ground to the docking guidance system. The docking guidance system
processes these status signals together with data from the other airport
systems shown in FIG. 15 and forwards, as a result, signals to the
airfield ground lighting system in order to control the lighting
equipment for the airfield ground. For example, if an aircraft is docked
at a particular gate, the lighting equipment of the airfield ground is
controlled in such a way that other aircraft, which have just landed and
need to be docked at a gate, for example, are not guided to the
particular gate that is currently occupied. In other words, the lighting
equipment is controlled such that the particular gate, at which the
aircraft is docked, is closed for other aircraft that are taxiing from
the runway to a parking position in accordance with and/or in response to
route prescribed by the control tower of the airport.
[0137] The user defined gate system and the docking guidance system
exchange user defined input data and reporting messages regarding the
status of the gate system, as indicated by the arrows between the user
defined gate system and the docking guidance system.
[0138] The airport database provides the docking guidance system with
information regarding the current status of the gates, e.g., whether or
not a particular gate is currently occupied by an aircraft that has
docked at the particular gate. In the reverse direction, the docking
guidance system provides the airport database with a time stamp so that
the gate status information can be associated with date and time
information, for example.
[0139] The central monitoring system checks the overall operation of the
docking guidance system by sending check demands to the docking guidance
system and by receiving check results from the docking guidance system.
[0140] FIG. 16 shows a software structure of the docking guidance system
(DGS) according to the present invention as it is preferably configured
for large airports having multiple terminals. The system architecture is
designed as a star configuration whose center includes a server for a
central control device (CWP). Preferably, more than one CWP server is
provided so that the docking guidance system functions reliably even if
one of the CWP servers fails.
[0141] The CWP server is connected to a plurality of CWP clients via a DGS
communications interface. These CWP clients are software packets, e.g.,
for operator stations for respective airport terminals or, in the case of
large terminals, for parts of the terminals themselves. The operator
stations may be computers or simply operator displays together with
keyboards. The CWP clients are arranged in the computer network of the
airport and control user interfaces of computers of a controller. The CWP
clients execute inputs of the controller, messages from docking guidance
subsystems associated with each gate, etc. Moreover, the CWP operator
stations may receive data from a flight information system.
[0142] In addition, the CWP server is connected to the gates via a DGS
network interface. These gates are, for example, associated with stand
alone systems proposed by Siemens AG, such as Siemens Docking Guidance
Systems (SIDOGS). These stand alone systems are described in more detail
below in connection with FIG. 20.
[0143] Furthermore, the CWP server is connected to interfaces to external
systems, such as a surface movement guidance and control system (SMGCS),
a central monitoring system (CMS), or other airport systems.
[0144] FIG. 17 shows a software structure of the docking guidance system
(DGS) according to the present invention as it is preferably configured
for mid-sized airports. In this preferred embodiment of the docking
guidance system according to the invention, the SIDOGS stand alone
systems are connected to one CWP operator station via the DGS network
interface. The CWP operator station is arranged at a ground control
station, for example, and is connected to interfaces to external systems,
such as a surface movement guidance and control system (SMGCS), a central
monitoring system (CMS), or other airport systems. The CWP may be
connected to the ground control station so that both docking information
and ground control information can be displayed on the same display of a
ground control station operator, for example. Thus, both the taxiing
process of aircraft on the airfield ground and the docking process of
aircraft at respective gates may be monitored and controlled by the
ground control station. Furthermore, the CWP operator station may receive
data from a flight information system.
[0145] FIG. 18 depicts a software structure of the docking guidance system
(DGS) according to the present invention as it is preferably configured
for small airports. Here, the SIDOGS stand alone systems are directly
connected to each other via the DGS network interface, which is a 100
Mbit Ethernet Hub, for example. In such an arrangement, the guidance of
an aircraft to a parking position at a particular gate may be carried out
by a neighbor gate of the particular gate.
[0146] The software structures described above may be differently designed
in accordance with the desires and requirements of the airport operator.
In particular, the size of the airport, cost considerations, safety
concerns, efficiency requirements, etc. determine the specific software
structure of a docking guidance system for a particular airport.
[0147] FIG. 19 shows a preferred architecture of the central control
device of the docking guidance system according to the present invention.
This preferred architecture includes software to control the terminals of
an airport; interfaces to external systems, such as those shown in FIG.
15; a network card for communicating with the network of the docking
guidance system; and an uninterruptable power system (UPS) to ensure
uninterrupted power supply to the central control device. The interfaces
to the external systems include, for example, an Ethernet interface or a
TCP/IP interface, an RS 422 interface, or an antenna. The network card of
the central control device is provided to communicate with a synchronous
transmission mode type network having a data rate of 155 Mbit/s, for
example. Furthermore, the central control device-is connected to a
control system for the apron of an airport. Thereby, relevant data
regarding the status of the apron, for example, are incorporated into the
docking guidance system. This results in improved efficiency and improved
safety of the docking process of aircraft, for example. Furthermore, by
connecting the CWP with the apron control station, both docking
information and apron control information can be displayed on the same
display of an apron control station operator, for example. Thus, both the
taxiing process of aircraft on the apron of the airport and the docking
process of aircraft at respective gates may be monitored and controlled
by the apron control station.
[0148] FIG. 20 shows an overview of a preferred embodiment of the Siemens
Docking Guidance System (SIDOGS). In this embodiment, each of gates 1 to
13 is associated with a docking guidance subsystem. These docking
guidance subsystems are interconnected via a network having a data rate
of 155 Mbit/s, for example. A particular docking guidance subsystem
includes a control computer, which is connected to and controls the
operation of a display, a TV camera, and a Local Operator Panel, as shown
in an exemplary manner for gate 1. The entire arrangement including the
network and the gates, together with their respective docking guidance
subsystems, is connected to a central working position, or central
control device, which monitors and controls the entire SIDOGS system.
[0149] The display includes information that indicates to the pilot of an
aircraft approaching the respective gate in which direction(s) the
aircraft should be moved in order to reach its final parking position at
the gate. More specifically, the vertical arrow on the display indicates
the distance the aircraft can or should be moved forward. The horizontal
arrow on the display indicates where the aircraft should be moved
laterally. Since the final parking position depends on the type of
aircraft, the display also indicates the aircraft type recognized by the
docking guidance subsystem, e.g., A320. In this way, the pilot is able to
check whether the correct aircraft type has been recognized.
[0150] In a preferred embodiment of the display, the vertical arrow
reduces its size as the pilot moves the aircraft forward. The lateral
movement of the aircraft may be indicated to the pilot by two horizontal
arrows, which face each other. If the pilot moves the aircraft laterally,
these two arrows move accordingly on the display. In the exemplary
situation shown on the display of gate 1 in FIG. 20, the pilot needs to
move the aircraft forward and further to the right in order to reach the
final parking position. As long as the point, at which the two tips of
the horizontal arrows touch each other, lies off-centered with regard to
the tip of the vertical arrow, the pilot must adjust the lateral position
of the aircraft accordingly. Once this point lies precisely above the tip
of the vertical arrow, the aircraft has reached the correct lateral
coordinate of the final parking position. The pilot can now move the
aircraft straight ahead so that the vertical arrow becomes shorter and
shorter until it finally disappears. At that point, the aircraft has
reached its final parking position.
[0151] The display may be located in the vicinity of the gate so that the
pilot watches the display through the windshield of the aircraft's
cockpit. Alternatively, the display information may be transmitted into
the cockpit via a wireless link. In this case, the pilot monitors the
movement of the aircraft on a display located in the cockpit.
[0152] The TV camera delivers information regarding the type and movement
of the aircraft to the control computer, as described earlier in
connection with FIGS. 1 and 2, in order to update the information on the
display.
[0153] Should the network fail, the docking guidance subsystem for each
gate is manually operated by the respective local operator panel.
[0154] FIG. 21 shows an exemplary screen display of the central working
position, or central control device, of FIG. 20. This screen display, as
well as other screen displays used in the docking guidance system
according to the present invention, may be a black-and-white display or a
color display. A screen section in the upper right corner shows a live
video display of the aircraft approaching the gate. The video display is
provided by the TV camera of FIG. 20, for example. Thereby, an operator
is able to monitor the actual docking process of the aircraft.
[0155] A screen section in the upper left corner displays schedule
information for individual gates, i.e., which aircraft type is scheduled
to be docked at which gate for which time of the day. For example, as
shown in FIG. 21, an aircraft of the B737-2 type is scheduled to be
docked at gate B30 approximately between 8:30 and 10:15.
[0156] A lower section of the screen display of FIG. 21 shows a schematic
overview of the gate arrangement of a particular airport and what the
current status of the gates is. For example, gate B36 is closed, as shown
in FIG. 21. In addition, this screen section indicates which aircraft
type is docked at which gate and what the current status of the
respective gate is, e.g., "prepared", "stop", or "closed". In a
"prepared" status, the gate is ready for docking an aircraft, for
example. In a "stop" status, the gate is currently occupied by an
aircraft docked at the gate, for example. In a "closed" status, the gate
is simply closed for operation.
[0157] FIG. 22 represents a preferred calibration system for calibrating
the angular field and/or position of the TV camera or video camera of the
docking guidance system according to the present invention. If the camera
is not calibrated, the camera will, e.g. over time, deliver erroneous
information as to the current position of an aircraft approaching the
respective gate. This, in turn, results in erroneous information on the
respective display shown in FIG. 20, so that the pilot is unable to
properly guide the aircraft to its parking position.
[0158] The SIDOGS system has the following functionalities. First, access
to the system is protected by passwords. Furthermore, several operator
stations may be arranged in the network of the system and different
authorizations can be granted to the users of the system. In addition,
interactions of the system operators with the system can be logged and
error messages may be printed on the operator screens or on an alarm
printer. Messages regarding the status of a selected gate are exchanged
in the system and a live video picture delivered by the TV camera or the
video camera is displayed in the control room of the system.
[0159] Since SIDOGS includes a schedule system as described above, the
docking process for aircraft can be started automatically at a scheduled
time. The network connections to the gate computers are automatically
tested and a graphical user interface is provided for installing new
gates, i.e., for integrating monitoring and control functions for docking
guidance subsystems associated with additional gates into the software of
the docking guidance system. For troubleshooting purposes, test programs
may be executed and, if there is an emergency situation, the system
operator may trigger an emergency stop of the system. Finally, the
docking process may be manually started by the operator, if necessary or
desired.
[0160] Since the SIDOGS operating system is based on the well-known
Windows (NT) software, the SIDOGS system has the advantage that no
special training for maintenance personnel is necessary. In addition,
since the interfaces to the external systems are open interfaces, the
external systems are easily connected to the SIDOGS system. SIDOGS can be
remotely accessed via a modem in order to carry out maintenance duties,
for example. Finally, it is a further advantage of the SIDOGS system that
additional gates can be easily integrated into the system.
[0161] The process of docking an aircraft at a gate is carried out in the
following exemplary manner. First, the operator of the SIDOGS system
selects the gate at which an approaching aircraft is to be docked.
Second, the type of the approaching aircraft is manually or automatically
selected at either the Gate Operator Panel (GOP) of the respective gate
or at the control center of the system. Subsequently, video data of the
aircraft approaching the gate, which are detected by the TV camera or the
video camera of the respective gate, are transmitted to the control
center. If necessary, the operator in the control center can influence
the docking process at any time. For example, in case of an emergency
situation, the system operator is capable of issuing an "emergency stop"
signal, which will halt the docking process in progress. Finally, status
messages of the docking process are transmitted to the control center, in
accordance with which the docking process is monitored and controlled.
[0162] The processing of the video data, e.g., gray tone images of the
aircraft approaching the gate, at which it is to be docked, is described
in more detail in connection with FIGS. 1 to 4 above. These gray tone
images are supplied to an evaluation unit. In a first step, the
evaluation unit filters the gray tone images to recognize edges in the
image. Subsequently, filtering in the time domain is used to extract
edges which move over time so that moving objects can be distinguished
from stationary objects. Certain outlines of the aircraft are then
compared with templates previously stored in the evaluation unit.
Thereby, the aircraft type and the current position of the aircraft are
recognized by the evaluation unit. The resulting data are forwarded to
the display, which is arranged outside the aircraft and/or inside the
aircraft, based on which the pilot moves the aircraft such that it
finally reaches its final parking position.
[0163] The above description of the preferred embodiments has been given
by way of example. From the disclosure given, those skilled in the art
will not only understand the present invention and its attendant
advantages, but will also find apparent various changes and modifications
to the structures and methods disclosed. It is sought, therefore, to
cover all such changes and modifications as fall within the spirit and
scope of the invention, as defined by the appended claims, and
equivalents thereof.
* * * * *