Note: Descriptions are shown in the official language in which they were submitted.
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TITLE OF INVENTION
Imaging System fox a Passenger Bridge or the like For Docking Automatically
With An Aircraft
BACKGROUND OF THE INVENTION
Modern airports are equipped with passenger bridges .located adjacent to
numerous gates on which passengers may walk safely protected from the weather
between the terminal building gate and the aircraft.
A known mobile-type passenger bridge includes a rotunda that is
connected to a terminal building. The bridge is rotatably mounted on a column
anchored in the ground. A passageway extends from the rotunda, which is made
up of a number of telescoping inter-fitting tunnel like elements, enabling
variation
of the length of the passageway. At the end of the passageway located farthest
25 away from the rotunda, there is provided a cabin which is pivotable in
relation to
tl~e passageway so as to align with the doorway of the aircraft. The
passageway
element to which the cabin is attached is suspended from a vertically
adjustable
frame, which in turn is supported by a bogie with wheels that can be driven
separately.
The passenger bridge normally occupies a parked position in the vicinity of
the place where the aircraft is to come to a halt after landing. When the
aircraft
has come to halt, an operator controls the passenger bridge vertically,
angularly,
and telescopically extends the passageway in the direction of the aircraft,
and
finally pivots the cabin such that the end of the bridge is connected to the
door of
the aircraft. The operation in the horizontal plane is achieved by altering
the
speeds of the bogie wheels in the relation to one another.
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Current Docking; Procedures
When the aircraft arrives the Ground Traffic Control (GTC) hands off the
aircraft to the Ramp or Apron Control (AC), once the aircraft leaves the
taxiway
for the terminal gate: The AC instructs the pilot to proceed to a specific
gate when
the pilot communications switches from GTC to AC. The AC instructs ramp crew
to be positioned to receive the aircxaft. The Ramp crew must have at least one
marshallex, who may activate the visual docking system or operate the paddles.
The aircraft may travel to its docking position by means of one engine ox two.
When the aircraft stops, the marshaller (who may also be the AC) will plug
into the aircraft for communication with the pilot. The passenger bridge
operatox
(which on occasion could be the marshallex) will then drive the passenger
bridge
(PB) to the aircraft door. The marshaller will then connect the ground power
from
the PB to the aircraft, APU. Due to the length of the cable on the cable reel,
the PB
must be against the aircraft in order to connect the APU. The aircraft door is
then
opened by the PB operator (fox some airlines), or the aircraft crew for other
airlines.
Departure
Approximately five minutes before "push back", the marshaller will
disconnect the ground power from the aircraft APU. Once the aircxaft door is
closed, the PB can be retracted but the PB operator must remain at the PB
controls
in case of an emergency evacuation. In practice, if there is a delay, the PB
operator
sometimes leaves to go operate a PB at another gate. This creates a problem
because the PB operator may not be available if the delay is suddenly
eliminated
and the pilot is ready for "push back". Generally, there will be the ramp lead
(connected to the aircraft for communications with the pilot}, a tow tractor
driver,
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and possibly one walker to watch for obstructions during "push back" involved
in
this operation.
Owing to its complexity, this operation requires operators with special
training, which of course is expensive for the airlines. Furthermore, it takes
a long
time to perform the connection. Also, it happens that the bridges bump into
the
aircraft as a result of error on the part of the operator, thus damaging the
aircraft.
Therefore the passenger bridge at airline terminals can be a cause of delay to
arriving and departing aircraft, because it is necessary to have a qualified
operator
move the passenger bridge. There are a limited number of qualified operators
and
during busy times they are in short supply and thus there may not be one
available when the aircraft arrives at the gate or is ready to depart from the
gate,
consequently the aircraft will be delayed until the operator arrives.
Applicants are aware of the following patent literature with respect to the
abovementioned subject matter:
. United States Patent 3,683,440 teaches an apparatus for aligning one o
more motorized terminal bridges to one or more doors in a vehicle enabling th
loading and unloading of passengers and freight. The subject patent provide
control of drive signals used to align the cab of a terminal bridge with a
door in
parked vehicle. It includes positional transducers which are coupled to varioL
movable sections of the bridge including the rotatable end of the bridge
attache
to the terminal, the expandable length passageway, the xotatable cab and tl~
variable height hydraulic cylinders connecting the truck which supports fY
bridge to the passageway. These transducers produce voltages indicative of tl
spa~ral position of the bridge as determined by the orientation of the varioi
movable sections. A television camera mounted in the cab enables an operate
stationed at a remotely located control panel to view the area around the
bridge c
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a television monitor. The cab can be rotated from the control panel as the
operator
views the monitor. Control circuits located in an electronics unit under the
cab
respond to signals from the control panel to produce initial positioning
signals
that rotate the bridge away from the terminal, extend the passageway, and
align
an electro-optical device to reflective type material affixed to the aircraft
in the
vicinity of the door. Positional voltages provided by the transducers and
electro-
optical device are processed in logic circuits disposed in the electronics
unit that
function in a prescribed manner to produce drive signals. These drive signals
guide the bridge along a path that will bring the cab into alignment with the
door.
As the cab approaches the door, the speed is automatically decreased until the
cab
contacts the vehicle. Pressure switches mounted around the perimeter of the
cab
opening contact the vehicle producing control signals which rotate the cab and
provide forward drive motion until complete contact of the cab opening 'and
the
vehicle is attained. A park indicator signal is then applied to the remotely
located
control panel and all power is turned off except that used in the control
circuitry
connected to the hydraulic cylinders. The electro-optical device mounted in
the
cab senses the height of the vehicle. If the vehicle height varies during
loading or
unloading, these switches provide signals to the control circuitry which will
produce drive signals to the hydraulic cylinders thereby maintaining the cab
at the
same level as the door. The bridge is automatically retracted from the vehicle
in
response to a control signal from the control panel and returned to its
original
position prior to activation. It is clear that the operation of this system is
operator
dependent in spite of the semi-automatic computer assisted aspects included.
All
of the drawbacks in the prior art identified above have therefore not been
addressed.
United S,.ates Patent 4,942,538 teaches a tele-robotic system adapted for
tracking and handling a moving object comprising a .robot manipulator, a video
monitor, an image processor, hand controls and a computer.
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United States Patent 5,226,204 teaches a tele-xobotic control apparatus for
aligning the movable end of a motorized passenger loading bridge to the door
in a
vehicle enabling the loading and unloading of passengers and freight.
United States Patent 6,330,726 teaches a bridge for the transfer of
passengers between an elevated level of a terminal building having a vestibule
attached to the terminal building.
European Patent 0781225 teaches a method of connecting one end of a
passenger bridge (1) or a goods-handling device of mobile type to a door on an
aircraft. The system requires that the aircraft type be identified in order
for the
correct windshield configuration to be provided.
United States Patent 3,642,036 teaches a system for automatically fueling an
automotive vehicle, comprising a movable fuel.dispenser including a nozzle
which
is adapted to be coupled to the fuel inlet of the vehicle, and programmable
moving
means connected to the fuel dispenser' to move same into a position where the
nozzle can be coupled with the fuel inlet.
United States Patent 3,91,196 teaches an apparatus for use in orienting
aircraft flight for refueling or other purposes.
United States Patent 6,024,137 teaches an automatic fueling system
including a pump having a . telescoping arm capable of placement in three-
dimensional space; a flexibly mounted nozzle on the end of the arm and a
docking
cone to mate with a fuel port on a vehicle. A camera provides a view of the
side of
the vehicle on a monitor with guides visible to the operator of the vehicle to
assist
in locating the vehicle within range of the pump. A light and a camera located
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adjacent to the nozzle are used to recognize retro-reflective light from an
annular
target about the intake port.
United States Patent 4,834,531 teaches a dead reckoning optoelectronic
intelligent docking system.
United States Patent 5,109,345 teaches an autonomous docking system
which produces commands for the steering and a propulsion system for a chase
vehicle used in the docking of that chase vehicle with a target vehicle.
United ~ States Patent 5,~34,~36 teaches an autonomous rendezvous and
docking system and method therefore.
United States Patent 3,65,692 teaches an apparatus for automatically
adjusting the floor of a moving vehicle to the height of a loading dock or
platform.
United States Patent 4,748,51 teaches a line-up vision system for testing the
alignment of a workpiece in a holder of an automated machining apparatus.
United States Patent 3,983,590 teaches a safety device for a loading bridge
or walkway, at which aircraft are parked, for loading and unloading of
passengers
and cargo through an open door in the aircraft.
United States Patent 5,105,495 teaches an array of non-contact proximity
sensors mounted on the front bumper of a~loading bridge to be in opposition to
the airplane.
United States Patent 5,552,983 teaches a variable referenced control system
for remotely operated vehicles.
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United States Patent 5,791,003 teaches a method and apparatus for variably
elevating a passenger boarding bridge platform.
United States Patent 5,855,035 teaches a method and apparatus for reducing
skidding of wheels on a passenger boarding bridge.
United States Patent 5,950,266 teaches a method and apparatus for
connecting a passenger boarding bridge to a movable body.
United States Patent 6,195,826 teaches an engagement structure adapted for
securement to the end of an aircraft boarding bridge including a bumper
assembly
formed of a first bumper and an auxiliary bumper.
United States Patent 3,883,918 teaches a telescopic connection for the
proximate end of an airport passenger bridge.
United States Patent 5,761,57 teaches a passenger boarding bridge for
servicing a commuter aircraft.
An object of this invention is, therefore, to address some of the problems in
the art.
It is therefore a primary object of this invention to provide an imaging
system adapted for a vehicle to be docked with an aircraft opening.
It is yet a further object of this invention to provide such a system which is
self initiating without the need of an operator.
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_$_
It is a further object of this invention to automate the controls of a
passenger
bridge using a camera based imaging system to sense the aircraft position and
drive the bridge to the appropriate door opening location.
Further and other objects of the invention will become apparent to those
skilled in the art when considering the following summary of the invention and
the more detailed description of the preferred embodiments illustrated herein.
SUMMARY OF THE INVENTION
According to a primary aspect of the invention there is provided an
automatic imaging system for, preferably initiating, the controlling,
positioning
and docking of a vehicle (for example a cargo loader, service vehicle, and
passenger bridge) with the opening of an aircraft without being informed of
the
aircraft type, said vehicle having driver means to move and raise/lower said
vehicle,
said system comprising a cluster of definitive, preferably retro-reflective,
targets located adjacent the opening of the aixcraft in a recognizable manner,
for
example as manufactured by the 3M Company, preferably Scotchlite~.
lighting means to focus on said targets when the aircraft is located at least
adjacent to an expected position , preferably pulsating lighting means
a camera, preferably at least one digital camera, disposed substantially
adjacent said lighting means and with a field of view directed parallel to
light
emanating from said lighting means so as to capture any reflected images of
said
target, and to generate images to communicate to a computer, and having a
field of
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view including said opening of the aircraft to cooperate with and preferably
be
synchronized with the preferably pulsating lighting means;
a computer disposed with said vehicle to process said images received from
said camera and to provide actuating signals to said driver means of said
vehicles,
software resident in said computer to provide an instruction set to said
computer as to how to process said image information and what actions to
commence in view of the information,
wherein. said imaging system automatically scans the area . whereat said
vehicle is expected and, once the targets are acquired as verified by the
computer ,
preferably initiates and controls the positioning and docking of the vehicle
with
the aircraft opening while maintaining constant observation of said targets.
Preferably said vehicle is selected from the group of equipment of
i) cargo hauling equipment;
ii) passenger facilities equipment; and
iii) a passenger boarding bridge;
or the like.
According to another aspect of the invention there is provided an imaging
system for identifying the location of ari aircraft opening or door and for
docking a
vehicle (for example, passenger, cargo, service or the like) with said
aircraft said
system comprising:
i) a passive target means, preferably at least one target and more
preferably a cluster of targets located preferably at the extremities of
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the opening or door, (preferably said target means being a retro-
reflective type, for example as manufactured by the 3M product
Scotchlite~;
ii) a target identification means including at least one camera having a
field of view including said opening or door of the
aircraft to
cooperate with and preferably be synchronized with
preferably
pulsating lighting means;
iii) preferably pulsating lighting means synchronized with
said target
identification means, preferably stroboscopic, for
lighting said target
means and providing for identification thereof by computer
means
in communication with said target identification means;
iv) computer means to process information (preferably at
least one
image processed to an enhanced image) from the target
identification
means and to compare the processed information (preferred
enhanced image) to an image retained in the memory
of said
computer means;
v) software means resident in said computer means to provide
the
instructions set and logic for said system to compare
processed
information including the.enhanced image with stored
information,
(preferably images) and to thereby determine the relevant
orientation, distance, and trajectories of the vehicle
to be
automatically docked with said aircraft based on the
system's
determination only;
vi) preferably said vehicle is selected from the group
of equipment of:
i) cargo hauling equipment;
ii) passenger facilities equipment; and
iii) a passenger boarding bridge; or the like.
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According to yet another aspect of the invention there is provided an
automatic computerized passenger boarding bridge control system, said bridge
having passenger bridge locomotion means to allow the bridge to move in
relation
to the aircraft, said system for use in conjunction with departing/arriving
aircraft
at an airport and comprising:
i) passive target means for identifying an exit/entrance doorway
irrespective of each aircraft type;
ii) target identification means, preferably at least one camera, to
identify when the aircraft containing the target means is proximate a
parking location adjacent a predetermined gate for the passenger
boarding bridge;
iii) position detection means for determining the physical location of the
passenger boarding bridge, including the angle of the wheels relative
to the telescopic tunnel, angle of the vestibule relative to the tunnel,
~ and fhe radius of curvature based upon gallery extension relative to
the pivot point on the terminal, to permit the computer to calculate
the trajectory of the passenger loading bridge and then instruct
locomotion means over the required path;
iv) computing means in communication with said target identification
means, said position detection means, and said passenger bridge
locomotion means, to activate said locomotion means and to provide
instruction to said bridge as to when and how to move based on
input from said target identification means, and said position
detection means, to receive and process all input system signals and
provide output system signals to said passenger bridge locomotion
means, to stop, move (preferably elevate or lower, pause, or
preferably steer in a p.tedetermined direction), to turn on and
synchronize the cameras and lights as necessary; and initiate any
warning lights, buzzer, horn or audible signals;
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v) preferably an obstacle recognition means, for example the device
commonly known as "safety hoop", to inform said computing means
that an obstacle is present preventing further motion of said bridge
and indicating the need for action by personnel to remove said
obstacle;
vi) lighting means to light said aircraft and to light the target means
when the aircraft is proximate the parked Iocation for the aircraft;
vii) software means resident in said computing means to provide the
instruction set and logic required to operate said system, to compare
processed information including the enhanced image with stored
information, (preferably images) and to thereby determine the
relevant orientation, distance, and trajectories of the vehicle to be
automatically docked with said aircraft based on the system's
determination only;
wherein said system allows for the movement of a passenger boarding bridge
during the departure and/or arrival of an aircraft without need for an
operator
thereof.
According to yet another aspect of the invention there is provided a
computerized automatic passenger boarding bridge control system, said bridge
having a passenger bridge locomotor to allow the bridge to move in relation to
the
aircraft, said system for use in conjunction with departing/arriving aircraft
at an
airport and comprising: .
i) at least one passive target for identifying an exit/entrance doorway
irrespective of each aircraft type;
ii) at least one camera, to identify when the aircraft containing the at
least one target is proximate a parking location adjacent a
predetermined gate for the passenger boarding bridge;
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iii) a position detector for determining the physical Iocafiion
of the
passenger boarding bridge, including the angle of
the wheels relative
to the telescopic tunnel, angle of the vestibule relative
to the tunnel,
and the radius of curvature based upon gallery extension
relative to
~ the pivot point on the terminal, to permit the computer
to calculate
the trajectory of the passenger loading bridge and
then instruct
locomotor over the required path;
iv) a computer in communication with said target identifier,
said
position detector, and said passenger bridge locomotor,
to activate
said locomotor and to provide instruction to said
bridge as to when
and how to move based on input from said target identifier,
and said
position detector, to receive and process all input
system signals and
provide output system signals to said passenger bridge
locomotor, to
stop, move (preferably elevate or lower, pause, or
preferably steer in
a predetermined direction), to turn on and synchronize
the cameras
and lights as necessary; and initiate any warning
lights, buzzer, horn
or audible signals;
v) preferably an obstacle recognizes to inform said computer
that an
obstacle is present preventing further motion of said
bridge and
indicating the need for action by personnel to remove
said obstacle;
vi) lighting to light said aircraft and to light the at
least one target when
the aircraft is proximate the parked location for
the aircraft;
vii) software resident in said computer to provide the
instruction set and
logic required , to operate said system, to compare
processed
information including the enhanced image with stored
information,
(preferably images) and to thereby determine the relevant
orientation, distance, and trajectories of service
equipment to be
automatically docked with said aircraft based on the
system's
determination only;
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wherein said system allows for the movement of a passenger boarding bridge
during the departure and/or arrival of an aircraft without need for an
operator
thereof.
Preferably the target identification means or target identifier of the
abovementioned system is a at least one digital camera.. Further the at least
one
target and the target means is made from retro-reflective material, for
example as
manufactured by the 3M Company, preferably Scotchlite~.
According to yet another aspect of the invention there is provided a
method of identifying the position of an opening, fox example a door or a
cargo
bay, or the like of an aircraft, said opening having a predetermined
perimeter; said
method comprising:
i) providing at least one passive target means (preferably a passive
reflective target such as that manufactured by the 3M company
under the trademark Scotchlite~) proximate the perimeter of said
opening and preferably when said opening is a door proximate the
corners of said door, and in another embodiment said target means
is provided as a cluster of targets proximate each corner of said door;
ii) focusing a preferably pulsing lighting means on said target, in one
embodiment being in the invisible spectrum such as infrared or the
like;
iii) . providing a target identification means and preferably at least one
camera and preferably a digital camera synchronized with said
lighting means and preferably housed together with said light to
provide raw data, preferably images to a computing means;
v) computing means for receiving information from said. target
identification means and preferably at least one camera to process
said information (in one embodiment provide enhanced images) and
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compare it to information stored in the _computing means and
thereby determine further action which might be taken based on the
identification of the position opening. Preferably said opening is
selected from the group of openings including a passenger door, a
cargo door, or the like, and preferably the opening is in the body of
an aircraft. In one embodiment a passenger bridge, or cargo
handling equipment is controlled by said computing means based on
identification of said target means, allowing for the docking of said
passenger bridge or cargo handling equipment with said aircraft and
the separation thereof when the aircraft is being loaded and
unloaded prior to the departure or arrival of the aircraft at a parked
location.
According to yet another aspect of the invenfiion there is provided a method
25 of identifying both the position of an opening, for example a door or a
cargo bay,
or the like, of an aircraft, and the type of said aircraft, while it is moving
towards
said passenger boarding bridge or parked at the gate, said method comprising:
i) providing at least one passive target means proximate the perimeter
of said opening, where the shape of said target means, or the number
of individual targets in the cluster, or the relative position of
individual targets in the cluster, uniquely identifies the type of
aircraft, for example using a machine readable pattern of reflective
tape; wherein the type of aircraft is enclosed in said pattern machine
recognizable code;
ii) focusing a preferably pulsing lighting means on said target, in one
embodiment being in the invisible spectrum such as infrared or the
like;
iii) providing a target identification means and preferably at least one
camera and preferably a digital camera synchronized with said
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lighting means and preferably housed together with said light to
provide raw data, preferably images to a computing means;
' , iv) computer means for receiving information from said taxget
identification means and preferably at least one camera to process
said information (in one embodiment providing enhanced images)
and compare it to information stored in the computing means based
on the identification of the position opening and of the aircraft type;
preferably said opening is selected from the group of openings
including a passenger door, a cargo door, ~or the like, and preferably
the opening is in the body of an aircraft; in one embodiment the
locomotion of a passenger bridge is governed by restrictions
imposed due to the aircraft type, for example when one of the
engines of the aircraft is in such proximity to said opening as to
necessitate maneuvering the passenger bridge around it or in such a
way as to prevent impacting said engine or allowing the passenger
bridge to be damaged by impact, heat radiation, exhaust fumes, or
other such hazards; in another example, in one or more specific
aircraft types, sensitive parts of the aircraft, for example the leading
edge of a wing, or an airspeed sensor, are located at such a proximity
to said opening as to force the passenger bridge to take a different
route or to contact the aircraft in such a way as not to damage the
sensitive part or parts of the aircraft, in such an embodiment, the
computing means, having received information about the aircraft
type from the camera, once said camera has identified the specific
aircraft type encoded within the target means, directs the locomotion
of the passenger bridge in such a way as is appropriate for the
specific aircraft type being approached.
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In a preferred embodiment said at least one camera embodied with any of
the abovementioned systems or methods may further comprise at least one
primary camera and at least one broad-view camera. Tn another embodiment of
the invention said at least one camera may further comprise a zoom lens. For
example said at least one primary camera or said at least one broad-view
camera a
may further comprise a zoom lens. In another embodiment said at least one
camera may further comprise a pan- or pan-and-tilt mount.
The present invention provides automated initiation or semi-automated
initiation for computerized control of a passenger personnel bridge, or
alternatively a cargo handling vehicle, to align the cab of the bridge with a
door in
a parked aircraft. A cluster of retro-reflective targets is strategically
placed
adjacent the door so as to be recognized by the computer. A manual override is
also provided for all functions as required.
The automatic function provides for the continuous monitoring and
operation of the gate area in standby mode unfit an arriving aircraft is
sensed,
which alerts the system until the aircraft has substantially parked at which
point
the computer initiates the docking procedure or a qualified individual does
so, for
example the marshaller, after which initiation the entire system is automated.
The
bridge includes positional sensors and drive actuators coupled to the various
movable sections of the bridge including the rotatable fixed pivoting end of
the
bridge attached to the terminal, the expandable length passageway, the
rotatable
cab with sensors indicating successful docking, and the variable height
hydraulic
cylinders connecting the truck which supports the bridge to the passageway.
These positional sensors produce signals to communicate with the computer
indicative of the position of the bridge in relation to the position of the
parked
aircraft as determined by the orientation of the various movable sections. A
digital camera (CCD) and a light (laser) may be mounted separately on fhe same
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side of the cab portion of the bridge, or preferably together in a single
housing on
the cab portion of the bridge, to both illuminate the targets and capture
images:
and to provide these raw images to the computer, also installed on the cab
portion
of the bridge. The digital images of the passive definitive retro-reflective
targets
positioned adjacent an opening of an aircraft are processed by the computer by
known methods as will be described hereinafter. These targets are readily
distinguished from other images by their definitive nature. They may be
positioned in clusters of two or more targets for improved accuracy.
Upon initiation of the system, the computer will pulse a narrow cone of
light synchronized with the camera shutter to view the general area Where the
aircraft is parked and observe the targets. Based on the view of the targets
~as seen
in the Figures the computer will determine and actuate the necessary steps to
align
the bridge with the aircraft opening, as the bridge is rotated about the
rotunda
away from the stowed position adjacent the gate while the computer continues
to
keep constant view of the targets, and following the extension of the tunnel,
the
cab can be rotated until in most cases the camera/light are substantially
normal to
the opening in the aircraft . The computer mounted on the cab of the bridge
responds to information provided by the images being processed and other
sensors provided to produce signals that rotate the bridge away from the
terminal,
extend the passageway, and align the cab with the targets. The images are
processed by the computer based on software based algorithms to produce drive
signals based on the computers understanding of the position of the cab
relative to
the opening. These drive signals guide the bridge along a path that will bring
the
cab into alignment with the door as the position information is updated by a
new
series of images as monitored by the computer. As the cab approaches the
opening, the speed thereof may be automatically decreased until the cab
contacts
the aircraft. Pressure switches may be mounted around the perimeter of the cab
opening contacting the aircraft to verify to the computer the complete contact
of
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the cab and the vehicle opening. An electro-optical device mounted in the cab
may be utilized to sense the height of the aircraft in relation to the cab. Tf
the
vehicle height varies during loading or unloading, these switches provide
signals
to the computer which will produce drive signals to the hydraulic cylinders
thereby;maintaining the cab at the same level as the opening.
The bridge may be automatically retracted from the aircraft, and returned
to its original stowed position prior to departure, in response to a signal to
the
computer initiated by the marshaller or be initiated by a sensor deterxnyxting
the
door has .been shut prior to departure and a further verification that
departure is
intended.
BRIEF DESCRIPTION OF THE DRAWINGS
The following figures illustrate the preferred embodiment of the invention,
wherein:
Figure 1 is a schematic view of the aircraft and bridge located apart from
one another prior to moving the bridge to the aircraft doorway.
Figure 2 is a flow diagram indicating the components of the system.
Figures 3A, 3B and 3C are examples of the targets that are used each
illustrated in an embodiment of the invention.
Figures 3D through 3G represent machine readable patterns for identifying
aircraft type illustrated in one embodiment of the invention.
Figures 4 to 15 illustrate the sequence of steps involving automatically
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initiating and docking a passenger bridge with an aircraft according to the
invention.
Figures 16 to 18 illustrate the logic utilized by the system of the invention
to
follow through the steps illustrated in Figures 4 to 15.
Figures 19 to 22 illustrate various images as observed by the camera
corresponding with the various positions of the bridge in this regard.
Figures 23 to 25 illustrate alternative vehicles which may be utilized with
this invention.
DETAILED DESCRIPTION OF THE DRAWINGS
The function of the system as seen in the figures is to automatically initiate
and control the movement of an airline terminal passenger bridge B into
position
to meet an arriving aircraft A, or to let a departing aircraft A leave the
terminal.
The system is either automatically initiated when an aircraft arrives or is
initiated
by an authorized individual. It will not be necessary for the authorized
individual
to have any special training in passenger bridge movement, only a familiarity
with
the system controls.
The imaging system as seen in the figures will consist of several elements
which combined together will be able to determine the location of the
passenger
bridge B as well as sense the location of the aircraft A. When commanded, the
system command will drive the bridge B in a safe manner, avoiding all
obstacles
on the ground, to the appropriate position commensurate with the command.
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For a departing aircraft A the system when commanded will move the
passenger bridge B several feet away from the aircraft A, sufficient to clear
the
fuselage.
When an aircraft A arrives at the gate the imaging system will determine
the passenger bridge location. It will, using its position sensing system,
determine
the aircraft location. Then, when the appropriate command is given, the system
will control the movement of the passenger bridge B, avoiding any obstacles on
the ground, into the correct position to access the passenger door 10, 11 of
the
arriving aircraft A.
Eduipment Description and Operation
Targets
There will be at least one retro-reflective target 10,11 located on the
aircraft
A to indicate the appropriate location for the passenger bridge B to contact
the
aircraft A. The target 10,11 is a passive symbol or object that can be easily
affixed
to the fuselage with no impact on the aircraft's airworthiness. The target is
distinctive as seen in figuxes 3A, B & C so that a position sensing system can
easily,
reliably and quickly identify it. The target 10,11 is kept in the cameras) 20
field of
view whether the passenger bridge B is in contact with the aircraft A or
whether it
is standing back from the aircraft A.
The targets 10, 11 is of a retro-reflector material that can be applied to the
aircraft as a peel and stick application.
Targets may be carefully placed in any predetermined location near the
door, as long as (a) their exact location relative to the door is known, and
(b) they
can been tracked by the camera. The ideal location is near the corners of the
door
which correspond with the placement of the cameras near the extremities of the
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passenger bridge. The targets are of retro-reflective materials, fox example
as:
manufactured by the 3M Company under the trademark of Scotchlite~. This
material includes glass micro-spheres bonded to a plastic base used to make
said
targets of a predetermined pattern having the required retro-reflective
properties
which enhance the visibility of the target clusters by the camera whether day
or
night conditions apply.
Initially the bridge is not assumed to be level with the door. In fact, the
bridge may be positioned in any arbitrary orientation relative to the
aircraft. The
actual position and orientation of the bridge can always be directly measured
by
the bridge sensors, and the imaging system can determine both the location and
the orientation of the surface on which the targets are located. Therefore,
the
absolute position and orientation of the aircraft can easily be calculated.
Neither
the cameras nor the bridge has to, necessarily, be normal to he target
surface. The
field of view of the cameras is sufficient to cover the area in which the
targets are
expected to be even when the bridge is not aligned with the door. As long as
the
targets are visible by at least one camera, the bridge drive may be used to
reposition the bridge cab-and hence the cameras-in a suitable orientation for
successful attachment to the aircraft door.
As a minimum, the system would employ one camera and one target
"cluster," for example a cluster consists of three or more individual
elements.
Since this imaging system relies on the apparent size and shape of such a
target
cluster to determine the location and orientation of the surface on which the
targets are placed (as seen in Figures 19 to 22), no additional data is needed
for
successful operation. In the preferred embodiment, one target cluster is used
for
each of a plurality of cameras; however, some or all cameras may share a
single
target cluster, and alternatively, more than one target cluster may be used by
some
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or all cameras. Tncreasing the number of target clusters will offer greater
accuracy,
fault tolerance, and reduce system complexity and cost.
The figures illustrate the bridge being normal to the door on approach; as
will usually be the case. However, as described above, this is not essential
for the
successful operation of the imaging system.
Machine Recognizable Pattern to Tdentify the Aircraft Type
In Figure (3D), a machine-recognizable pattern for identifying the aircraft
type is shown. In this example, the pattern is comprised of up to six
individual
elements. For this example, the specific type of aircraft is identified by
using
elements number 1, 3, 4, and 6. Using such a system, in theory, up to 64
different
aircraft types may be encoded. In practice, many of the 64 patterns should be
avoided since they may result in ambiguous interpretation by the vision
system,
or to reduce the probability of a mistaken interpretation.
In Figure (3E), a different pattern is shown, this time, with elements numbex
1, 2, 5 and 6 being used.
As seen in Figures (3D) and (3E), the pattern is located in a fixed position
relative to the main target cluster used for determining the position of the
aircraft
relative the passenger bridge. This allows the vision system to easily locate
each
individual element of the target pattern, and decode the aircraft type by
observing
which of the individual pattern elements is present, and which is absent.
In Figures (3F) and (3G), an,alternate method is used to encode the aircraft
type. When using this method, certain geometrical properties of the patern are
used to identify the aircraft type, for example, the relative distance between
pairs
of lines are used to encode the aircraft type.
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In Figure (3F), the pattern is comprised of three lines. The two outermost
lines are "goalposts", essentially determining the envelope of the whole
pattern,
while the position of the iiliddle "indicator" line encodes the information.
In this
figure, the indicator line is 60% of the distance between the left and the
right
- goalpost lines (so that the distance between the left goalpost line and the
indicator
is 1.5 times larger than the distance between the indicator and the right
goalpost
line).
In Figure (3G), the same method is used as in Figure (3F), but this time the
indicator line is 80% of the distance between the left and the right goalpost
lines
(so that the distance between the left goalpost line and the indicator is 4
times
larger than the distance between the indicator and the right goalpost line).
The amount of information that can be encoded using the pattern shown in
Figures (3F) and (3G) depends on the inherent resolution and accuracy of the
camera means and the image processing software.
The image processing software uses this information, encoded in the ratio
between the different spacing between the three Iines, to convey data about
the
aircraft type. For example, the pattern in Figure (3D) and (3F) may correspond
to a
Boeing 737-300 aircraft, while the pattern in Figure (3E) and (3G) may
correspond
to an Airbus-320 aircraft.
"Bowtie" Tax~et Pattern Figure
In figure (3C), a preferred pattern for a single target is shown. This pattern
has several features allowing it to be easily recognizable and to give an
accurate
positional reading:
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1. This type of "checkerboard" pattern is 'unnatural', in the sense that it is
very unlikely to appear unintentionally as a part of another object that the
camera means is viewing.
2. The sharp contrast between the dark and the bright portions make it easier
for the camera means to discern even in poor visibility conditions.
3. The shape of this individual target is not significantly altered when
viewed
from an angle, as opposed to being viewed "head on".
4. All features of the pattern are large, monochrome areas, as opposed to thin
lines or dots. This makes it easier to discern using camera means which is of
limited resolution, or alternately, allows for. a larger viewing distance.
5. The main featuxe of this pattern is the crosshair at the exact centre of
the
pattern. This crosshair is presented as the border between alternating dark
and bright areas.
6. The "crosshair" feature mentioned above is built of a horizontal and a
vertical line. This makes it very easy to enhance and process using a
standard rectangular matrix CCD and simple image enhancing software. To
benefit from this property, the target has to be mounted such that the
crosshaix lines are parallel to the camera sensor matrix X and Y axes.
7. Other than the "crosshair" feature, no part of the pattern contains any
~ horizontal or vertical borders or lines. This means that when the image
enhancing software described above is used, the crosshair feature-and
only the crosshair feature-will be enhanced. This intersection between the
horizontal and vertical lines provide for a sharp, unique feature on the
target to be used as the centroid for the full target.
~. Since the shape is a well-defined, simple geometric shape, it is easy to
reproduce accurately and cheaply.
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Camera s
Cameras) 20 will be the input device for the position sensing system. The
cameras) 20 will be dixected towards the parked, arriving aircraft A and will
have
the target 10,11 within their field of view. The output of the cameras will be
transmitted directly to the Central Processing Unit (CPU) 40.
There will be lights 30 mounted adjacent to the cameras) 20, which will
illuminate
the aircraft A and the target 10,11.
The camera 20 and lights 30 will be mounted in a suitable position on the
20 exterior of the passenger bridge B. The location will be determined to
provide the
best, unobstructed view of a parked aircraft.
At least one camera must be present to provide sensing of target. A
plurality of cameras offers increased accuracy and fault tolerance. In a
preferred
embodiment, two digital cameras, for example CCD cameras, are used, mounted
one on each side of the passenger bridge or access-way. To provide useful
stereoscopic vision by the cameras, the cameras should be mounted at a
sufficient
distance from each other to offer different views of the targets.
The cameras will be pointed in such a way that the main optical axes of all
cameras are parallel to each other. Alternatively, cameras may be pointed to
an
arbitrary point near the estimated location of the targets once the aircraft
is in its
final parked position.
The lens used by the cameras will be selected such that the focal length
would pxovide a field-of view sufficiently wide to cover the aircraft approach
zone, while still offering sufficient resolution to accurately measure the
position of
individual targets in the target groups: In a preferred embodiment, since the
cameras are mounted on the passenger access-way, a field of view of 20
degrees,
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for example, provides coverage for the aircraft access zone while the bridge
is
retracted. Once the aircraft is parked and the bridge or access-way starts its
motion towaxds the aixcraft door, the decreasing distance to the target would--
without any further provision provide a larger view of said targets. At the
final
stages of approach of the bridge or access-way to the aircraft, the targets
would
occupy all or most the cameras field of view, providing optimal target
resolution
at the time when it is most important.
Alternatively, an additional "broad-view" camera may be utilized in
addition to the normal primary view camera, mounted in such a way or fitted
with
a wide-angle lens as to provide a view of the aircraft approach zone. When
used in
this manner , the cameras) will be used for pointing the bridge or access-way
to
the targets, and then using a narrower field of view lens, allowing for higher
taxget
resolution.
Alternatively, a variable focal length "zoom" Iens may be used in the
camera.
When used, the cameras) will initially start with a short focal length,
providing a wide-angle view for approach. The focal length will then be
increased
in steps or continuously as the bridge or access-way approaches the targets.
When
used in such a way, a provision is made for the computer to detect or measure
the
focal length of each lens at any given moment, in order to correctly calculate
the
actual distance of the cameras from the targets.
. In another embodiment, the camera, (or all cameras jointly, or each of a
plurality of cameras independently) , is mounted on a pan- ox pan-and-tile.
gimbal,
where the pan- or pan-and-tilt motion is controlled by the computer. Tn this
embodiment, the motion of said cameras) may be controlled independent of the
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motion of the bridge or access-way. This allows for the cameras) to scan the
aircraft access zone even when the bridge or access-way are located or pointed
in
such a way as would otherwise impede the operation of cameras) affixed to the
bridge frame without such pan- or pan-and-tilt maneuverability. When used in
this manner, the computer controls the motion of all camera gimbals, and is .
equipped with sensors to detect the momentary yaw, or yaw and pitch, of the
cameras. Such pan- or pan-and-tilt apparatus rnay alternatively or conjointly
be
used for the broad-view camera mentioned above.
In . a preferred embodiment, the rotary- motion of the final joint of the
passenger bridge (the "cab") may be used to pan the cameras) to scan for an
approaching aircraft, and to point said cameras) in an optimal direction to
detect
the targets and direct motion of bridge or access-way towards the targets.
The ability to determine the position and orientation of the surface on
which the targets are located is a direct result of the placement of the
targets
adjacent the aircraft operung/door and the subsequent computer processing of
the
geometrical observations of the cameras. A stereoscopic vision alternative
embodiment is provided as a means to enhance the spatial accuracy of the
invention. The method for using two cameras to create stereoscopic vision is a
standard practice in the field of Machine Vision, and is a straightforward
implementation for anyone skilled in the art.
A preferred Charge-Coupled Device (CCD) camera is recommended and
has become the standard for electronic cameras and digital photography.
Examples include: Dalsa IM15; JAI CV-A1; Pulnix TM-200; Hitachi KP-F110;
COHU 6612-3000.
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Electronic cameras mounted with a zoom lens usually use a servo
mechanism which controls the adjustment of the focal length. In such a
configuration, the computer would both command a specific focal length, and
receive the current actual focal length of the zoom lens as input to the
calculation.
When the cameras) are mounted on a pan- or pan-and-tilt gimbal, a servo
mechanism is used to control the gimbal angles. Reference is made to US
6,191,842
(and/or US 5,900,925) and US 5,633,681 in this regard the teachings of which
in
relation to pan- or pan and-tilt gimbal are hereby incorporated by reference .
Other examples are available as well.
Li~htin~
At least one light source will be affixed to each camera, preferably by
enclosing both camera and said light source in a single enclosure, allowing
the
light source to be aimed in bore-sight to cover the axea observed by said
camera.
The efficiency of the lighting source in the embodiments of the invention is
enhanced in one or more of the following methods:
1) Limiting the spectrum: a lighting source may employ a
monochromatic light, for example a LASER emitter, or a filtered
floodlight, or a special-purpose light bulb which is rich in one part of
the spectrum. When such a monochromatic light source is combined
with a matching filter in the camera, the contrast of the image
illuminated by the lighting means is greatly enhanced, providing for
easier discerning and discrimination of the target.
2) Stroboscopic lighting: by using short bursts of light, as opposed to
continuous illumination, and synchronizing the camera with the
short illuminated periods, the effective illumination of the target
may be greatly enhanced, while maintaining the apparent amount of
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light visible to the human eye to a minimum, and reducing overall
power consumption. This has the benefit of avoiding harsh lighting
which may interfere with the pilots and other personnel in the
vicinity.
3) Extending beyond visible light: to further reduce interference to
personnel, or in lieu of the methods above, lights using an invisible
part of the spectrum may be used. Infrared light is the preferred
choice, since it is cheap, powerful, and harmless. An appropriate
infrared filter will then be added to the camera means to reduce
extraneous light interferences from being observed by the camera.
4) An additional secondary "out-of-line" light source may be added to
the system to further enhance contrast. This secondary light source
would be placed away from the imaginary line connecting the
camera and the target. When such secondary Iight source is used,
the camera will fixst acquire an image while only the primary (bore-
sight) light source is illuminating the target. This would be followed,
in rapid succession, by acquiring an image when only the second
light source is illuminating the target. The two images would then
be subtracted from each other by the computer. Since the targets are
designed to reflect light only in the direction from which they are lit,
the targets would appear considerably brighter when lit by the
primary light source than when lit by the secondary light source,
while the rest of the image would generally appear approximately
the same. Subtracting the two images would tend to produce a
highly-enhanced image in which only the targets are visible, making
target discrimination much easier.
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When such. secondary lighting is used, one such source is common to all
cameras. Alternatively, the primary light source may be attached to one camera
and may be used as the secondary light source for all other cameras, if the
angular
distance between said cameras is suffia.ently large.
Just like the sight on a rifle, each camera and its accompanying light have to
poznt to the same direction, cover the same (conical) field of view, and be in
close
proximity to each other. When using a telephoto lens and narrow-beam light
source, this alignment involves careful calibration of camera with light in a
common fixture. With standard field of view equipment, such calibration is not
needed. Providing the camera and light source in a common pre-machined fixture
would by itself force the two to be aligned in such a "bore-sight°'
manner. The
proximity of camera and corresponding light source is desirable because of the
retro-reflective characteristic , of the targets. Since the targets are
designed to
reflect light substantially only in the direction from which that light has
arrived,
the cameras have to be positioned close enough to the light in order to
readily
receive the light reflected by the target and target clusters.
If a telephoto lens and a narrow-beam source are utilized, the calibration
process can be completed during the fabrication and assembly phase. Once the
combined unit is built and sealed, no further individual alignment between
camera and light. is needed. The combined unit may still have to be aligned
with
the area in which the targets are expected to appear. Please note that such
narrow
field of view cameras would generally be used only in conjunction with one or
more "broad-view" cameras, as described herein.
Most strobo~~copic light sources, as well as most electronic cameras (such as
used in the preferred embodiment) can be "slaved" to an external trigger. Such
an
external trigger controls the exact moment at which a strobe will emit a pulse
of
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light, and when an electronic camera will sample the data on its sensor. By
sending the same external trigger signal to both the light source and the
camera at
once, the system guarantees that the image will be "observed" by the camera at
the same moment as the pulsing of the strobe. This is similar in concept to
the
operation of a flash attached to a standard camera, where the flash is
synchronized
to the film shutter via an integral shoe on the camera for the flash or via
separate
connectors.
In the preferred embodiment, the trigger signal to the cameras and to the
stroboscopic light sources is issued by the computer. Tf a plurality of
cameras is
used, the triggers for different camerajlight pairs may be staggered, for
increased
target discrimination ability. Each of the plurality of cameras would observe
the
targets only when the light source attached to that camera 'is illuminating
the
targets, without interference by light sources attached to the other cameras.
Bride Location Determinator
The movement of the passenger bridge B first requires that the current
location is known. To determine the passenger bridge location several methods
could be used. Four possible options are briefly described. A device to
continuously sense the rotation and steering direction of the passenger bridge
drive wheels could provide the location. An alternative method to provide the
location would be to sense the bridge segments translation and the angular
position of the bridge B with respect to the terminal. A third option would be
to
place targets immediately below the passenger bridge B or on the terminal and
use
an additional camera to determine the location of the passenger bridge B. The
current position of the bridge B, would be communicated to the CPU and during
bridge motion, this position would be continuously updated.
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Another approach is to use a GPS/INS (inertial navigation system) to
continuously locate the passenger bridge B. Such a system might be produced by
a company in Markham Ontario, Canada called Applanix. The advantage to the
third and fourth option system is that they would be able to be attached to an
existing bridge with out having to make any modification to the bridges
operating
systems.
Object Avoidance
To safely operate the passenger bridge B automatically, there is a
requirement for an object avoidance system. This system will recognize
equipment, objects or personnel that would be in the path of the moving
passenger bridge B and command the bridge B to stop. There is an object
avoidance system installed on some Ford Windstar~ vans. The system would
communicate directly with the CPU.
Another approach is to use a device commonly known as a "safety hoop",
which is a ring-shaped contact switch circumscribing the passenger bridge
"bogey"
driving wheel bay. This safety hoop is installed in such a way as to sense
contact
with objects or personnel in its path, and to immediately shut off the motors
driving the bridge. When using such a safety hoop, it may either be connected
to
the CPU, or connected directly to the drive motors, cutting off supplies once
activated.
Central Processing Unit (CPU)
The Central Processing Unit will contain the microprocessor, input and
output devices and signal conditioning devices to communicate with and control
the other system elements. The position sensing and bridge drive commands will
be performed by software residing in the CPU. Other functions, such as the
bridge
location determinator and the object avoidance, will also be software
controlled.
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The bridge will move to meet an arriving aircraft A either auto-initiated or
initiated by an authorized individual. The target 10,11 of the parked aircraft
A
will be in the camera's 20 field of view so the target 10,11 can be "acquired"
by the
system. With the.target acquired, the position of the bridge B will be
compared to
the target position and the bridge B will be commanded to move toward the
aircraft target 10,11. The object avoidance system will be functioning to
ensure
that the area in the path of the bridge B is clear of objects. Once the bridge
B has
made contact with the aircraft A the system will revert to a safe mode.
For departure from the gate, the system will auto-initiate upon sensing the
aircraft door is closed to be initiated by an authorized individual. The gate
will
move away from the aircraft while the position sensing system continuously
determines the relative location of the aircraft A and the passenger bridge B.
The
object avoidance system will be functioning.
As seen in Figures 19 to 22 a fixed image would look different depending
on the point from which it is viewed. If the position of the camera viewing
the
image is known, the different views can be used to derive the position of the
image. A known pattern of figure 19 is used as the target, and a known
cameras)
position (on the cab) is used to calculate the location and orientation of the
surface
on which the targets are located, in this case the door/opening of an
aircraft.
Referxing to Figures 19 to 22, the target clusters are shown in four different
views relative to the camera. In Figure 19, the targets are located on a
surface
normal to the camera viewing direction, and fairly close to the camera (actual
distance would depend on actual size of target cluster and focal length). In
Figure
A, the targets are at the same height as the camera, but to the left of it
(the two left
targets appear closer to each other than the two right ones, meaning the right
ones
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are further away). In Figure 10, 11 the targets are far above the camera, and
slightly to the left of it. In figure 22, the targets are in the same
direction as they
are in Figure 10,11, but they are farther away from the camera. Once the
position
of the targets has been calculated relative to the camera (and hence relative
to the
bridge), the bridge can be controlled by insticuctions from the computer to
move
towards the door. Any inaccuracies in such motion can be quickly corrected,
since
the targets are in constant view by the camera, and the targets position
relative to
the camera/bridge is continuously updated. Both the position and the
orientation
of the door can be calculated by the computer from the appearance of the
targets,
hence both the bridge position and its attitude can be controlled for optimal
attachment to the aircraft door.
Software
The flow charts provided herein in Figures 16 to 18 are self explanatory.
Referring now to Figures 4 through 18 the present invention provides automated
initiation or semi-automated initiation for computerized control of a
passenger
personnel bridgel0 , or alternatively a cargo handling vehicle, to align the
cab of
the bridge with a door in a parked aircraft A. A cluster of retro-
reflective'targets
10, 11 are strategically placed adjacent the door so as to be recognized by
the
computer. A manual override is also provided for all functions as required.
The automatic function provides for the continuous monitoring and
operation of the gate area in standby mode until an arriving aircraft A is
sensed,
which alerts the system until the aircraft has substantially parked at which
point
the computer initiates the docking procedure or a qualified individual does
so, for
example the marshaller, after which initiation the entire system is automated.
The
bridge B includes positional sensors and drive actuators coupled to the
various
movable sections of the bridge including the rotatable fixed pivoting end of
the
bridge R attached to the terminal, the expandable length passageway T, the
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rotatable cab C with sensors indicafiing successful docking, and the variable
height
hydraulic cylinders connecting the truck which supports the bridge to the
passageway. These positional sensors produce signals to communicate with the
computer indicative of the position of the bridge in relation to the position
of the
parked aircraft as determined by the orientation of the various movable
sections.
A digital camera (CCD) and a light (laser) may be mounted separately on the
same
side of the cab portion C of the bxidge B , or preferably together in a single
housing
on the cab portion C of the bridge B , to both illuminate the targets 10, 12
and
capture images and o provide these raw images to the computer, also installed
on the cab portion C of the bridge B. The digital images of the passive
definitive
retro-reflective targets positioned adjacent an opening of an aircraft are
processed
by the computer. These targets are readily distinguished from other images by
their definitive nature. They may be positioned in clusters of two or more
targets
for improved accuracy.
Upon initiation of the system, as seen in Figures 16 to 18 the computer will
pulse a narrow cone of light as seen in figure 6 synchronized with the camera
shutter to view the general area where the aircraft is parked and observe the
targets 10 and 11. Based on the view of the targets as seen in the Figures 19
through 22 the computer will determine and actuate the necessary steps to
align of
the bridge B with the aircraft opening, as the bridge B is rotated about the
rotunda
R away from the stowed position adjacent the gate G while the computer
continues to keep constant view of the targets 10 and 11 , and following the
extension of the tunnel T , the cab C can be rotated until the camera/light
are
substantially normal to the opening . The computer mounted on the cab of the
bridge B responds to information provided by the images being processed and
other sensors provided to produce signals that rotate the bridge B away from
the
terminal, extend the passageway T, and align the cab C with the targets 10 and
11.
The images are processed by the computer based on software based algorithms to
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produce drive signals based on the computers understanding of the position of
the
cab C relative to the opening. These drive signals guide the bridge B along a
path
that will bring the cab C into alignment with the door as the position
information
is updated by a new series of images as monitored by the computer. As the cab
C
approaches the opening, the speed thereof may be automatically decreased until
the cab C contacts the aircraft A. Pressure switches may be mounted around the
perimeter of the cab opening contacting the aircraft to verify to the computer
the
complete contact of the cab and the vehicle opening. An electro-optical device
mounted in the cab may be utilized to sense the height of the aircraft in
relation to
the cab. If the vehicle height varies during loading or unloading, these
switches
provide signals to the computer which will produce drive signals to the
hydraulic
cylinders thereby maintaining the cab at the same level as the opening.
The bridge may be automatically retracted from the aircraft, and returned
to its original stowed position prior to departure, in response to a signal to
the
computer initiated by the marshaller or by initiated by a sensor determ»i"g
the
door has been shut prior to departure and a further verification that
departure is
intended.
Operator Controls
The system should be integrated into the existing operator controls so that
the passenger bridge B can either be automatically or manually controlled. The
required controls, should as a minimum include an on and off switch far the
system, a command switch to initiate bridge withdrawal from the aircraft A and
a
command switch to initiate the passenger bridge approach to the aircraft. In
addition there will be indicators giving the status of the system and the
current
location. But overall the controls skiould be as simple as possible to allow a
minimally trained authorized individual to initiate operation of the bridge B.
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Present Imag~g System Advantages Over Prior Art
By automating the placement/removal of the passenger bridge to the
aircraft a labour savings will be realized resulting in a reduction in delays.
Further
fuel savings will result with the reduction of the idling of aircraft engines
during
delays. Faster throughout is anticipated through a limited number of gates and
a
reduction in aircraft damage is expected.
Expected Advantages To Be Realized Tn Part
Annual fuel consumption by APUs at gate is over 1.5 million litres
~ One aircraft is damaged by a ramp accident every 1700 departures
~ Ramp accidents at B gates costs about $2.5 million/year
~ Global cost of ramp accidents is over $2 billion
~ The cost of an aircraft delay is estimated at $50. per minute
Passen eg_ r Brid, ,ge Types
~ Apron drive
~ Radial drive
~ Fixed telescoping
~ Custom mix of above 3
~ . Regional aircraft
Operator Controls/Indicators
~ automatic/manual (system on/off)
~ bridge engage aircraft
~ bridge disengage aircraft
~ system status indicator
~ Maintenance Controls/Indicators
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One object is to retrofit existing bridges ox alternatively include with OEM's
an imaging system to automatically initiate and guide a bridge from a stowed
position to dock with an aircraft when parked.
Other Vehicles that could utilize the invention for "docking" with an
aircraft are self propelled cargo loaders, catering/cabin service trucks and
passenger transfer vehicles as seen in Figures 23 through 25. Each of these
vehicles
must also be precisely maneuvered into position, elevated to the correct
height,
and then make gentle contact with the aircraft. In all three cases the
illustrated
vehicles would also have a camera, a light and a computer mounted on them in a
similar manner as described in relation to the passenger bridge embodiment.
.All
vehicles would include sensing and actuating devices similar to the ones used
on
the passenger bridge. There will be no need for an obstacle detection device
or the
position determinator function since an operator will move the vehicle into
initial
position. The software resident in the computer otherwise would be very
similar
to that used for the passenger bridge. The targets and target acquisition
algorithms
would be almost identical, however the software would be tailored to drive the
appropriate vehicle.
An example of a Cargo Loader as seen in figure 25 is Manufactured by FMC
Airline Equipment as found on their Internet Web site (www.fmcairline.com).
FMC make several sizes of these cargo loaders for different capacity loads.
The
loaders consist of two platforms that can be raised and lowered. The vehicle
is
positioned so that one platform is adjacent to and level with the cargo floor.
The
other platform is used to receive cargo at ground level, elevate it to the
height of
the first platform and transfer it to that platform. The initial approach and
docking
with the cargo hold could be automated by using an embodirrtent of the
invention.
This would m;n~rn~ze the training required for the operator since the final
docking
would be performed under computer control. To accommodate differences in the
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location of -the targets for a cargo hold door compared to the targets for
passenger
door the soft ware would be modified to recognize the cargo door pattern.
An example of a Catering/Cabin Service Truck may be as. Manufactured
by the Stinax Corporation as found at their Internet Web site
(,www.stinar.com) or
Manufactured by the Global Ground Support Company as found at their Internet
Web site (www.~;lobal-llc.com) These two manufacturers make similar vehicles
as
seen in Figure 24 and Figure 24.A., which can be used to supply the galley of
the
aircraft with food and beverages and remove waste associated with food
service.
Alternatively the vehicles can be used to transport cabin service cxew and
their
tools to the aircraft and also to remove garbage and waste from the aircraft
after
cleaning. The vehicle consists of a conventional truck chassis with a scissor
lift. A
van body is attached to the scissor lift so that it can be raised from the
truck bed to
the height of a cabin door. Since the provision of food and beverages is done
on
wheeled carts the location and height must be precise.. The initial approach
and
docking with the passenger door could be automated by using an. embodiment of
invention described above.
An example of a Passenger Transfer Vehicle may be as Manufactured by
Accessair Systems Inc, as found at their Web site (www.accessairsystems.com).
This vehicle as shown in figure 23 is similar to a bus in that it carries
passengers
from the terminal to the aircraft. However unlike a bus where the passengers
have
to exit and climb stairs to board the aircraft, the body of the vehicle
elevates to the
same level as the aircraft passenger door so the passengers can board with out
using stairs. The initial approach and docking with the passenger door could
be
automated by using the invention. This automation would permit the PTV to be
operated by a less skilled person.
In review therefore, as seen in Figure 4 as the aircraft A arrives at gate G
the
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passenger bridge B is disposed at the position indicated with the rotunda R
being
attached to the gate or terminal G and the tunnel T extending there from to
cabin
C at the terminus thereof. Aircraft A therefore arrives at the parked location
P. As
seen in figure 5 the target clusters 10 and 11 are located proximate the door
opening. As seen in figure 6 the lights housed with the digital camera 20
shine a
cone of light on the targets 10 and 11 when the airplane A is substantially
parked
the camera and light are disposed in a common housing 20 on cabin C. Based on
the orientation of the targets as seen by the computer referring to figures 19-
22 the
computer will be able to determine the position of the passenger bridge and
the
cabin relative to the door opening. This was described above. The light will
therefore continue to be focused on the cluster of targets 10 and 11 and the
tunnel
T will rotate with respect to the aircraft A while the camera 20 housed with
the
lights 30 continues to provide images to the computer and until such time as
the
wheels W reach a position were in the tunnel is fully pivoted as seen in
figure 12
wherein the tunnel will extend toward the aircraft A while the images continue
to
be fed to the computer of the cluster 10 and 11 and now with the clusters
appearing as in figure 19 the tunnel will extend towards the aircraft as seen
in
figure 14 and dock therewith as seen in figure 15.
While the foregoing provides a detailed description of the preferred and
alternative embodiments of the invention, it is to be understood that this
description is illustrative only of the principles of the invention and not
limitative.
Furthermore, as many changes can be made, to the invention without departing
from the scope of the invention, it is intended that all material contained
herein be
interpreted as illustrative of the invention and not in a limiting sense.
