U.S. patent application number 14/800179 was filed with the patent office on 2017-01-19 for aircraft systems and methods to monitor proximate traffic.
This patent application is currently assigned to HONEYWELL INTERNATIONAL INC.. The applicant listed for this patent is HONEYWELL INTERNATIONAL INC.. Invention is credited to Jitender Kumar Agarwal, Sandeep Chakraborty, Satyanarayan Kar, Sanjib Kumar Maji.
Application Number | 20170018194 14/800179 |
Document ID | / |
Family ID | 56557471 |
Filed Date | 2017-01-19 |
United States Patent
Application |
20170018194 |
Kind Code |
A1 |
Maji; Sanjib Kumar ; et
al. |
January 19, 2017 |
AIRCRAFT SYSTEMS AND METHODS TO MONITOR PROXIMATE TRAFFIC
Abstract
An aircraft system for an own-ship aircraft includes an ADS-B
unit configured to receive ADS-B messages with flight information
from other aircraft over a plurality of time periods, the other
aircraft including a first aircraft. The system further includes a
database configured to store at least a portion of the flight
information associated with the other aircraft over the plurality
of time periods. The system further includes a processing unit
configured to compare the flight information for a current time
period to the flight information for a previous time period to
identify missing flight information from the current time period
relative to the previous time period, the missing flight
information including the flight information associated with the
first aircraft, and initiate an annunciation to an operator of the
own-ship aircraft based on the missing flight information
associated with the first aircraft.
Inventors: |
Maji; Sanjib Kumar;
(Bangalore, IN) ; Kar; Satyanarayan; (Bangalore,
IN) ; Chakraborty; Sandeep; (Kolkata, IN) ;
Agarwal; Jitender Kumar; (Muzaffarnagar, IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HONEYWELL INTERNATIONAL INC. |
Morristown |
NJ |
US |
|
|
Assignee: |
HONEYWELL INTERNATIONAL
INC.
Morristown
NJ
|
Family ID: |
56557471 |
Appl. No.: |
14/800179 |
Filed: |
July 15, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G08G 5/0008 20130101;
G08G 5/0078 20130101; G01S 13/06 20130101; G08G 5/0021
20130101 |
International
Class: |
G08G 5/00 20060101
G08G005/00; G01S 13/06 20060101 G01S013/06 |
Claims
1. An aircraft system for an own-ship aircraft, comprising: an
Automatic Dependent Surveillance-Broadcast (ADS-B) unit configured
to receive ADS-B messages with flight information from other
aircraft over a plurality of time periods, the other aircraft
including a first aircraft; a database coupled to the ADS-B unit
and configured to store at least a portion of the flight
information associated with the other aircraft over the plurality
of time periods; a processing unit coupled to the ADS-B unit and
the database and configured to compare the flight information for a
current time period to the flight information for a previous time
period to identify missing flight information from the current time
period relative to the previous time period, the missing flight
information including the flight information associated with the
first aircraft, wherein the flight information in the ADS-B
messages include, for each of the other aircraft, an aircraft
identification, a position, an altitude, and a time stamp to
identify the respective time period, and initiate an annunciation
to an operator of the own-ship aircraft based on the missing flight
information associated with the first aircraft wherein the
processing unit is configured to identify the missing flight
information associated with the first aircraft when a time elapsed
between the time stamp associated with the most recently received
ADS-B message from the first aircraft and the current time period
exceeds a predetermined threshold; and a display device coupled to
the processing unit and configured to display the annunciation,
wherein the processing unit is configured to evaluate the flight
information for the current time period to identify proximate
aircraft from the other aircraft and to display a traffic display
on the display device with the annunciation that includes at least
first icons representing the proximate aircraft, wherein the
annunciation includes a text annunciation associated with the first
aircraft, and wherein the text annunciation associated with the
first aircraft includes the aircraft identification, the position,
and the altitude from the most recently received ADS-B message from
the first aircraft, the text annunciation further including the
time elapsed between the time stamp associated with the most
recently received ADS-B message from the first aircraft and the
current time period.
2. (canceled)
3. (canceled)
4. (canceled)
5. (canceled)
6. (canceled)
7. (canceled)
8. (canceled)
9. An aircraft system for an own-ship aircraft, comprising: an
Automatic Dependent Surveillance-Broadcast (ADS-B) unit configured
to receive ADS-B messages with flight information from other
aircraft over a plurality of time periods, the other aircraft
including a first aircraft; a database coupled to the ADS-B unit
and configured to store at least a portion of the flight
information associated with the other aircraft over the plurality
of time periods; a processing unit coupled to the ADS-B unit and
the database and configured to compare the flight information for a
current time period to the flight information for a previous time
period to identify missing flight information from the current time
period relative to the previous time period, the missing flight
information including the flight information associated with the
first aircraft, wherein the flight information in the ADS-B
messages include, for each of the other aircraft, an aircraft
identification, a position, an altitude, and a time stamp to
identify the respective time period, and initiate an annunciation
to an operator of the own-ship aircraft based on the missing flight
information associated with the first aircraft, wherein the
processing unit is configured to identify the missing flight
information associated with the first aircraft when a time elapsed
between the time stamp associated with the most recently received
ADS-B message from the first aircraft and the current time period
exceeds a predetermined threshold; and a display device coupled to
the processing unit and configured to display the annunciation,
wherein the processing unit is configured to evaluate the flight
information for the current time period to identify proximate
aircraft from the other aircraft and to display a traffic display
on the display device that includes at least first icons
representing the proximate aircraft, wherein the processing unit is
configured to determine an estimated current position of the first
aircraft based on the position of the first aircraft from the most
recently received ADS-B message from the first aircraft, compare
the estimated current position of the first aircraft to an intended
flight path of the own-ship aircraft, and display, when the
estimated current position of the first aircraft is proximate to
the intended flight path of the own-ship aircraft, a second icon
representing the estimated current position of the first aircraft
on the traffic display.
10. The aircraft system of claim 9, wherein the processing unit is
further configured to determine a level of an uncertainty
associated with the estimated current position of the first
aircraft and to display an outline of a zone area surrounding the
second icon on the traffic display that is sized based on the level
of uncertainty.
11. The aircraft system of claim 10, wherein the processing unit is
configured to generate a message requesting updated information for
the first aircraft, and wherein the aircraft system further
comprises a communication unit coupled to the processing unit and
configured to send the message to air traffic control.
12. The aircraft system of claim 11, wherein the communication unit
is configured to receive the updated information from air traffic
control, wherein the processing unit is configured to update a
position of the second icon on the traffic display based on the
updated information, and wherein the processing unit is further
configured to update or remove the outline of the zone area
surrounding the second icon on the traffic display.
13. The aircraft system of claim 9, further comprising sensors
coupled to the processing unit and configured to collect data about
the first aircraft in a flight environment, and wherein the
processing unit is configured to estimate the position of the first
aircraft based on the data from the sensors.
14. A method for monitoring aircraft traffic on an own-ship
aircraft, comprising the steps of: receiving first messages with
flight information from other aircraft during a first time period;
evaluating the flight information to identify proximate aircraft
from the other aircraft relative to the own-ship aircraft;
displaying symbology representing at least the proximate aircraft
on a traffic display of a display device; storing the flight
information for each of the proximate aircraft; receiving second
messages with flight information from at least a portion of the
other aircraft during a second time period; comparing the flight
information from the second messages with the flight information
from the first messages to identify missing flight information in
the second time period, the missing flight information being
associated with at least a first aircraft of the other aircraft;
and generating an annunciation based on the missing flight
information for the first aircraft, wherein the generating step
includes generating a warning when a time elapsed between the
second time period and the first time period is greater than a
predetermined threshold, and wherein the generating step includes
generating the annunciation as a text annunciation that includes a
first aircraft identification, a first aircraft position, and a
first aircraft altitude from the first messages and the time
elapsed.
15. (canceled)
16. (canceled)
17. The method of claim 14, further comprising estimating a current
position of the first aircraft, comparing a flight path of the
own-ship aircraft to the estimated current position of first
aircraft, and displaying symbology on the traffic display
representing the estimated current position of the first aircraft
when the estimated current position of the first aircraft conflicts
with the flight path of the own-ship aircraft.
18. The method of claim 17, further comprising determining a level
of uncertainty associated with the estimated current position of
the first aircraft, and wherein the displaying step includes
displaying the symbology with an outline of a zone area on the
traffic display that is sized based on the level of
uncertainty.
19. The method of claim 18, further comprising generating a message
requesting updated information for the first aircraft; sending the
message to air traffic control; receiving the updated information
from the air traffic control; and updating the symbology based on
the updated information, including updating or removing the outline
of the zone area.
20. The method of claim 17, further comprising collecting updated
information about the first aircraft with a sensor; and updating
the symbology based on the updated information about the first
aircraft.
21. The aircraft system of claim 9, wherein the processing unit is
configured to display the annunciation with the traffic
display.
22. The aircraft system of claim 21, wherein the annunciation
includes a text annunciation associated with the first
aircraft.
23. The aircraft system of claim 22, wherein the text annunciation
associated with the first aircraft includes the aircraft
identification, the position, and the altitude from the most
recently received ADS-B message from the first aircraft, the text
annunciation further including the time elapsed between the time
stamp associated with the most recently received ADS-B message from
the first aircraft and the current time period.
24. The aircraft system of claim 1, wherein the processing unit is
configured to determine an estimated current position of the first
aircraft based on the position of the first aircraft from the most
recently received ADS-B message from the first aircraft, compare
the estimated current position of the first aircraft to an intended
flight path of the own-ship aircraft, and display, when the
estimated current position of the first aircraft is proximate to
the intended flight path of the own-ship aircraft, a second icon
representing the estimated current position of the first aircraft
on the traffic display.
25. The aircraft system of claim 24, wherein the processing unit is
further configured to determine a level of an uncertainty
associated with the estimated current position of the first
aircraft and to display an outline of a zone area surrounding the
second icon on the traffic display that is sized based on the level
of uncertainty.
26. The aircraft system of claim 24, further comprising sensors
coupled to the processing unit and configured to collect data about
the first aircraft in a flight environment, and wherein the
processing unit is configured to estimate the position of the first
aircraft based on the data from the sensors.
Description
TECHNICAL FIELD
[0001] The present invention generally relates to aircraft systems
and methods, and more particularly, to systems and methods for
monitoring traffic in an area around the aircraft during
flight.
BACKGROUND
[0002] Computer generated aircraft displays have become highly
sophisticated and are used to provide flight crews with real-time
visual representations of flight management, navigation, and
control information. As a result, such displays have become
effective visual tools for controlling aircraft, reducing pilot
workload, increasing situational awareness, and improving overall
flight safety.
[0003] As one example, a traffic display presents the operator with
the relative positions of other aircraft in the vicinity of the
aircraft during flight. The positions of the traffic relative to
the aircraft may be determined based on Automatic Dependent
Surveillance-Broadcast (ADS-B) messages received by the aircraft.
Generally, ADS-B messages are broadcast by aircraft to other
aircraft and air traffic control to enable the recipient of the
message to determine the position of the broadcasting aircraft. As
a result of this arrangement, the traffic display may be dependent
on continuously receiving accurate ADS-B messages from other
aircraft. However, for various reasons, such ADS-B messages may not
be received, thereby potentially impacting the accuracy of the
traffic display.
[0004] Accordingly, it is desirable to provide systems and methods
that provide improved traffic monitoring and display during flight.
Furthermore, other desirable features and characteristics of the
present invention will become apparent from the subsequent detailed
description of the invention and the appended claims, taken in
conjunction with the accompanying drawings and this background of
the invention.
BRIEF SUMMARY
[0005] In accordance with an exemplary embodiment, an aircraft
system for an own-ship aircraft includes an Automatic Dependent
Surveillance-Broadcast (ADS-B) unit configured to receive ADS-B
messages with flight information from other aircraft over a
plurality of time periods, the other aircraft including a first
aircraft. The system further includes a database coupled to the
ADS-B unit and configured to store at least a portion of the flight
information associated with the other aircraft over the plurality
of time periods. The system further includes a processing unit
coupled to the ADS-B unit and the database and configured to
compare the flight information for a current time period to the
flight information for a previous time period to identify missing
flight information from the current time period relative to the
previous time period, the missing flight information including the
flight information associated with the first aircraft, and initiate
an annunciation to an operator of the own-ship aircraft based on
the missing flight information associated with the first
aircraft.
[0006] In accordance with another exemplary embodiment, a method is
provided for monitoring aircraft traffic on an own-ship aircraft.
The method includes receiving first messages with flight
information from other aircraft during a first time period;
evaluating the flight information to identify proximate aircraft
from the other aircraft relative to the own-ship aircraft;
displaying symbology representing at least the proximate aircraft
on a traffic display of a display device; storing the flight
information for each of the proximate aircraft; receiving second
messages with flight information from at least a portion of the
other aircraft during a second time period; comparing the flight
information from the second messages with the flight information
from the first messages to identify missing flight information in
the second time period, the missing flight information being
associated with at least a first aircraft of the other aircraft;
and generating an annunciation based on the missing flight
information for the first aircraft.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present invention will hereinafter be described in
conjunction with the following drawing figures, wherein like
numerals denote like elements, and wherein:
[0008] FIG. 1 is a functional block diagram of an aircraft system
to monitor aircraft traffic in accordance with an exemplary
embodiment;
[0009] FIG. 2 is a flowchart of a method for monitoring aircraft
traffic in accordance with an exemplary embodiment;
[0010] FIG. 3 is a traffic display rendered by the aircraft system
of FIG. 1 in a first scenario in accordance with an exemplary
embodiment;
[0011] FIG. 4 is a traffic display rendered by the aircraft system
of FIG. 1 in a second scenario in accordance with an exemplary
embodiment; and
[0012] FIG. 5 is a traffic display rendered by the aircraft system
of FIG. 1 in a third scenario in accordance with an exemplary
embodiment.
DETAILED DESCRIPTION
[0013] The following detailed description is merely exemplary in
nature and is not intended to limit the invention or the
application and uses of the invention. Furthermore, there is no
intention to be bound by any theory presented in the preceding
background or the following detailed description.
[0014] Broadly, exemplary embodiments described herein provide
aircraft systems and methods that monitor and display traffic
information. More specifically, the systems and methods correlate
currently received Automatic Dependent Surveillance-Broadcast
(ADS-B) messages with previously received ADS-B messages to
identify aircraft for which an ADS-B message has not been recently
received, thereby indicating a possible problem with the ADS-B
system of the other aircraft. Depending on a number of factors,
such aircraft may be identified as missing traffic. In various
embodiments, the systems and methods may send a message to air
traffic control regarding the missing traffic, present information
about the missing traffic to the operator, and/or evaluate the
missing traffic for display or warnings.
[0015] FIG. 1 is a block diagram of an aircraft system 100 in
accordance with an exemplary embodiment. It should be understood
that FIG. 1 is a simplified representation of the system 100 for
purposes of explanation and ease of description. Further exemplary
embodiments of the system 100 may include additional or other
devices and components for providing further functions and
features. The system 100 can be utilized in an aircraft, such as a
helicopter, airplane, or unmanned vehicle. Moreover, exemplary
embodiments of the system 100 can also be utilized in spacecraft,
ships, submarines, and other types of vehicles. For simplicity,
exemplary implementations are described below with reference to
"aircraft."
[0016] As described below, the system 100 is particularly useful
during flight to monitor other aircraft (e.g., "traffic") in the
vicinity of the aircraft. In one exemplary embodiment, the system
100 is typically housed and implemented on the own-ship aircraft to
enable an operator to monitor other aircraft within a broadcast
range, although one or more components may also be located external
to the aircraft. Generally, unless otherwise noted, the term
"aircraft" refers to the own-ship aircraft associated with the
aircraft system 100
[0017] As shown in FIG. 1, the system 100 includes a processing
unit 110, a database 120, a navigation system 130, a flight
management system 140, sensors 150, a communication unit 160, an
ADS-B unit 170, and a display device 180 coupled together in any
suitable manner, such with as a data bus. Although the system 100
appears in FIG. 1 to be arranged as an integrated system, the
system 100 is not so limited and can also include an arrangement
whereby one or more aspects of the system 100 are separate
components or subcomponents of another system located either
onboard or external to the aircraft. Additional details about the
function and operation are provided below after a brief
introduction of the components of the system 100.
[0018] The processing unit 110 may be a computer processor
associated the various aircraft functions discussed below. In one
exemplary embodiment, the processing unit 110 functions to at least
receive and/or retrieve aircraft flight management information
(e.g., from the flight management system 140), navigation and
control information (e.g., from the navigation system 130), and
target, terrain, and/or traffic information (e.g., from the
database 120, sensors 150, communication unit 160, and/or ADS-B
unit 170). As introduced above and discussed in further detail
below, the processing unit 110 includes a traffic unit 112 that
monitors and evaluates traffic information, and as appropriate,
initiates messages to air traffic control (ATC), and presents
information associated with the traffic to the operator, e.g., in
the form of a visual traffic display. Accordingly, the processing
unit 110 may function as a graphics display generator to generate
display commands based on algorithms or other machine instructions
stored in the processing unit 110, database 120, or other memory
components. The processing unit 110 then sends the generated
display commands to display device 180 for presentation to the
user.
[0019] Depending on the embodiment, the processing unit 110 may be
implemented or realized with a general purpose processor, a content
addressable memory, a digital signal processor, an application
specific integrated circuit, a field programmable gate array,
suitable programmable logic device, discrete gate or transistor
logic, processing core, discrete hardware components, or any
combination thereof. In practice, the processing unit 110 includes
processing logic that may be configured to carry out the functions,
techniques, and processing tasks or methods associated with
operation of the system 100. In one exemplary embodiment, the
processing unit 110 is implemented with on-board logic to provide
the functions described below in real-time to the aircraft
operator. In other embodiments, one or more aspects may be located
remotely and/or evaluated at a later time.
[0020] Although not shown, the processing unit 110 may include a
user interface coupled to the processing unit 110 to allow a user
to interact with the display device 180 and/or other elements of
the system 100. The user interface may be realized as a keypad,
touchpad, keyboard, mouse, touch panel, joystick, knob, line select
key or another suitable device adapted to receive input from a
user. In some embodiments, the user interface may be incorporated
into the display device 180, such as a touchscreen. In further
embodiments, the user interface is realized as audio input and
output devices, such as a speaker, microphone, audio transducer,
audio sensor, or the like.
[0021] Database 120 is coupled to processing unit 110 and can be a
memory device (e.g., non-volatile memory, disk, drive, tape,
optical storage device, mass storage device, etc.) that stores
digital landing, waypoint, target location, and terrain data as
either absolute coordinate data or as a function of aircraft
position that enables the construction of a synthetic or enhanced
representation of the aircraft operating environment. Database 120
can additionally include other types of navigation and/or
operational information relating to the evaluation and display of
information. Data in the database 120 may be uploaded prior to
flight or received from external sources, such as an airport and
other aircraft transmissions and/or onboard sensors. As described
below, the database 120 may be used to store aircraft traffic
information received from various sources.
[0022] The navigation system 130 is configured to provide the
processing unit 110 with real-time navigational data and/or
information regarding operation of the aircraft. The navigation
system 130 may include or cooperate with a global positioning
system (GPS), inertial reference system (IRS), Air-data Heading
Reference System (AHRS), or a radio-based navigation system (e.g.,
VHF omni-directional radio range (VOR) or long range aid to
navigation (LORAN)). The navigation system 130 is capable of
obtaining and/or determining the current state of the aircraft,
including the location (e.g., latitude and longitude), altitude or
above ground level, airspeed, pitch, glide scope, heading, and
other relevant flight information.
[0023] The flight management system 140 supports navigation, flight
planning, and other aircraft control functions, as well as provides
real-time data and/or information regarding the operational status
of the aircraft. The flight management system 140 may include or
otherwise access one or more of the following: a weather system, an
air traffic management system, a radar system, a traffic avoidance
system, an autopilot system, an auto-thrust system, a flight
control system, hydraulics systems, pneumatics systems,
environmental systems, electrical systems, engine systems, trim
systems, lighting systems, crew alerting systems, electronic
checklist systems, an electronic flight bag, and/or other suitable
avionics systems. As examples, the flight management system 140 may
identify operating states of the aircraft, such as engine operation
and current aircraft configuration status, including information
regarding the current flap configuration, aircraft speed, aircraft
pitch, aircraft yaw, aircraft roll, and the like. Additionally, the
flight management system 140 may identify or otherwise determine
environmental conditions at or near the current location of the
aircraft, such as, for example, the current temperature, wind
speed, wind direction, atmospheric pressure, and turbulence. The
flight management system 140 may also identify optimized speeds,
distance remaining, time remaining, cross track deviation,
navigational performance parameters, and other travel
parameters.
[0024] The system 100 may include or otherwise receive information
from one or more sensors 150. In one exemplary embodiment, the
sensors 150 may include light sensing devices, such as a visible
low light television camera, an infrared camera, and millimeter
wave (MMW) camera. Other sensors 150 may include, as examples,
radar, lidar, sonar, and/or weather sensors that may provide
information to the system 100. In some embodiments, the sensors 150
may be incorporated into the navigation system 130, flight
management system 140, or enhanced vision systems. As described
below, the sensors 150 may particularly function to collect
information about the position, nature, and arrangement of aircraft
traffic during flight.
[0025] The communication unit 160 may be any suitable device for
sending and receiving information to and from the system 100. In
some embodiments, communication unit 160 may be configured to
receive radio frequency transmissions, satellite communication
transmissions, optical transmissions, laser light transmissions,
sonic transmissions or transmissions of any other wireless form of
data link. In one exemplary embodiment, the communication unit 160
is configured to send and/or receive information with air traffic
control . As described below, the communication unit 160 may
exchange automated or selected messages with air traffic control
about traffic, either as text-based messages, voice communications,
or other forms. The communication unit 160 may interpret received
communications and present this information to the processing unit
110.
[0026] As previously noted, the ADS-B unit 170 is coupled to the
processing unit 110. Generally, ADS-B unit 170 functions as part of
a cooperative surveillance mechanism for air traffic management and
related applications. In one exemplary embodiment, the ADS-B unit
170 includes a transponder that automatically and periodically
transmits messages that include state vector data (e.g., flight
information) for the broadcasting aircraft. Such aircraft state
vectors may include, as examples, aircraft position, airspeed,
altitude, intent (e.g., whether the aircraft is turning, climbing,
or descending), aircraft type, and flight number. The aircraft
state vectors may be provided to the ADS-B unit 170 for
transmission as ADS-B messages by the processing unit 110 or other
systems. The ADS-B unit 170 similarly receives ADS-B messages with
state vectors from other aircraft in a broadcast area and provides
the received ADS-B messages to the processing unit 110 for
evaluation and, as appropriate, additional action, as discussed
below. In some embodiments, the ADS-B messages sent by the ADS-B
unit 170 may be referenced as "ADS-B OUT" and the ADS-B messages
received by the ADS-B unit 170 may be referenced as "ADS-B IN."
[0027] The system 100 also includes the display device 180 coupled
to the processing unit 110. The display device 180 may include any
device or apparatus suitable for displaying various types of
computer generated symbols and flight information discussed above.
Using data retrieved (or received) from the navigation system 130,
flight management system 140, database 120, sensors 150,
communication unit 160, and/or ADS-B unit 170, the processing unit
110 executes one or more algorithms (e.g., implemented in software)
for determining the position of the various types of desired
information on the display device 180. As noted above, the
processing unit 110 then generates display commands representing
this data, and sends display commands to the display device 180.
Any suitable type of display medium capable of visually presenting
multi-colored or monochrome flight information for a pilot or other
flight crew member can be provided, such as, for example, various
types of CRT displays, LCDs, OLED displays, plasma displays,
projection displays, HDDs, HUDs, and the like. Additional details
regarding the information displayed on the display device 180 are
provided below.
[0028] As described below, the system 100 is particularly suitable
for monitoring, evaluating, and presenting air traffic information
to the operator during flight. During operation, the traffic unit
112 of the processing unit 110 may determine or otherwise receive
the current position and energy parameters (e.g., altitude, track,
etc.) of the aircraft (e.g., via the navigation system 130 or
flight management system 140). The traffic unit 112 may also
receive ADS-B messages from other aircraft (e.g., via the ADS-B
unit 170). The traffic unit 112 is configured (i.e., processing
unit 110 is loaded with, and operates, appropriate software,
algorithms and/or sub-routines) to evaluate the position and energy
parameters of the other aircraft relative to the own-ship aircraft
and to generate display commands for the display device 180 to
render appropriate traffic information. In most situations, the
system 100 graphically displays the traffic information on the
display device 180 to provide an accurate depiction of the other
aircraft within the vicinity of the own-ship aircraft based on the
ADS-B messages. However, in one exemplary embodiment, the
processing unit 110 is configured to monitor and evaluate aircraft
from which messages are not received, and in some situations, the
processing unit 110 is configured to alert the pilot and/or air
traffic control about missing messages from other aircraft. The
reasons for the system 100 failing to receive an ADS-B message from
other aircraft may vary, including an issue with the transponder of
the ADS-B unit of the other aircraft (e.g., a malfunction or
intentional or accidental ADS-B deactivation). Regardless of the
reason, the system 100 functions to identify those aircraft while
anticipating or addressing possible resulting issues. In
conventional systems, such traffic may simply disappear from a
traffic display without notice by the operator. Additional details
regarding the operation and resulting display of the system 100 are
provided below.
[0029] FIG. 2 is a flowchart of an exemplary method 200 to monitor,
evaluate, and display traffic information to an aircraft operator
on an aircraft display device. In one exemplary embodiment, the
method 200 may be implemented by the system 100 of FIG. 1. As such,
FIGS. 1 and 2 are referenced in the discussion below. It should be
appreciated that method 200 may include any number of additional or
alternative tasks, and the tasks shown in FIG. 2 need not be
performed in the illustrated order. Generally, the method 200 is
implemented or executed in an iterative manner within a current
time period (or at a current point in time) with consideration for
previous time periods (or previous points in time). In one
exemplary embodiment, the time period may generally correspond to
the frequency of receiving ADS-B messages, e.g., every second,
although other time periods may be considered or implemented. In
one exemplary embodiment, the method 200 may be selectively
implemented under certain conditions. As an example, the method 200
may be active at particular altitudes, locations, or flight phases
and inactive during other situations.
[0030] In a first step 205, the aircraft system 100 receives ADS-B
messages from other aircraft within a broadcast area. As noted
above, these messages may include the aircraft flight
identification (ID), position, altitude, and track. In one
exemplary embodiment, the messages may be received by the ADS-B
unit 170 and provided to the traffic unit 112. The aircraft system
100 may further receive traffic information from additional or
other sources, including a traffic collision avoidance system
(TCAS), a traffic information service broadcast (TIS-B) and/or an
automatic dependent surveillance rebroadcast (ADS-R), which may be
received and/or processed with the communication unit 160, flight
management system 140, and/or the processing unit 110. This
information may also be provided to the traffic unit 112.
[0031] In a second step 210, the traffic unit 112 or other
component of the aircraft system 100 evaluates the flight
information in each of the messages to determine the proximity of
the other aircraft. In particular, the traffic unit 112 may
evaluate the position, altitude, and track of the other aircraft
relative to the position, altitude, and track of the own-ship
aircraft. Based on this information, the traffic unit 112
identifies the other aircraft that are proximate to the own-ship
aircraft. Such proximity range may be considered with respect to a
predetermined range (e.g., flight time or distance) from a present
(or future) position of the aircraft. The predetermined range may
be selected by operator and/or set by regulation, policy, or other
source. The aircraft within the predetermined proximity may be
considered proximate aircraft or proximate traffic, while the
aircraft outside of the predetermined proximity range may be
considered non-proximate aircraft or non-proximate traffic.
[0032] In step 215, the traffic information is presented to the
operator. The traffic information may include information regarding
proximate and non-proximate traffic, as well as applicable alerts.
The traffic information may be presented to the operator in the
form of a traffic display. Reference is briefly made to FIG. 3,
which is a traffic display 300 that may be presented on the display
device 180.
[0033] In FIG. 3, the traffic display 300 is centered on the
own-ship aircraft, represented by symbol or icon 302. One or more
range rings 304 may be depicted to provide a distance or timing
context. As shown, the traffic display 300 also includes symbology
(e.g., in the form of a chevron or diamond icon) representing each
aircraft that forms the traffic 311-315. In some embodiments, the
traffic 311-315 corresponds to all instances of aircraft from which
flight information was received. The traffic 311-315 on the traffic
display 300 provides an indication to the operator of the
respective positions of the other aircraft relative to the own-ship
aircraft 302 in real-time. In addition to position, the symbology
representing the traffic 311-315 may include various types of
information. In particular, the traffic 311-315 may include an
aircraft ID, the relative altitude, and the change in relative
altitude. For example, aircraft 311, which has an aircraft ID of
"ABC1," is positioned approximately 1000 feet below the own-ship
aircraft (as indicated by the "-10") and is moving vertically down
(as indicated by the down arrow). Typically, the operator
continuously monitors the traffic display 300 to maintain awareness
about traffic 311-315.
[0034] The symbology representing each aircraft of the traffic
311-315 also identifies the respective aircraft as proximate
traffic or non-proximate traffic. In the depicted embodiment,
traffic 311, 312 is non-proximate traffic, as represented by the
hollow or empty icons, and traffic 313-315 is proximate traffic, as
represented by the filled or solid icons. Other symbology
indicating the proximity of the traffic 311-315 may be
provided.
[0035] Although only five instances of traffic 311-315 are depicted
in FIG. 3, the traffic display 300 may include many more instances
of traffic, depending on the flight environment. As described
below, the method 200 enables the identification of "missing"
proximate traffic that may otherwise be overlooked if disappearing
from numerous other instances of proximate traffic.
[0036] As described above, the position and appearance of the
images and other symbology on the traffic display 300 may be
dynamically generated by the traffic unit 112 of the processing
unit 110 based on input from the database 120, navigation system
130, flight management system 140, sensors 150, communication unit
160, and/or ADS-B unit 170. In one exemplary embodiment, the
traffic display 300 is overlaid on a black background. In further
embodiments, the traffic display 300 is overlaid on terrain
symbology in the form of a moving map display. Additionally,
although the traffic display 300 is depicted as a two-dimensional
plan view, the traffic display 300 may also be represented as a
three-dimensional and/or elevation view, as well as from
perspectives other than the own-ship aircraft. Although not shown
in FIG. 3, the traffic display 300 may present alerts to the
operator, including the resolution alerts and traffic alerts.
[0037] Returning to FIG. 2, in step 220, the traffic unit 112 or
other component of the aircraft system 100 stores the traffic
information associated with proximate traffic from the messages of
step 210. The information may be stored, for example, in the
database 120. The stored proximate traffic information may include
a record or entry that includes, for example, the aircraft ID,
position, altitude, track, and time stamp to indicate the time at
which the message was received.
[0038] In steps 225 and 230, the traffic unit 112 or other
component of the aircraft system 100 evaluates the stored proximate
traffic information for the current time period relative to
previous time periods. In particular, the traffic unit 112
correlates received proximate traffic information to stored
proximate traffic information in order to identify aircraft that
may be "missing." In other words, the traffic unit 112 identifies
aircraft for which proximate traffic information is expected to be
received but was not received, as described below.
[0039] In step 225, the traffic unit 112 evaluates the traffic
records associated with proximate traffic for the current time
period relative to previous time periods. In particular, the
traffic unit 112 identifies traffic records for proximate traffic
that have been previously received and that were not received in
the present time period. Such identification may be implemented by
correlating the current proximate traffic information to previously
stored proximate traffic information based on, for example,
aircraft identification. The aircraft with records that were
previously received but did not have ADS-B messages received in the
current time period may be referred to below as "potential missing
traffic." As described below, the records associated with potential
missing traffic are subsequently evaluated to identify if the
potential missing traffic may be temporary ignored for the current
time period, identified as missing proximate traffic, and/or prompt
an alert.
[0040] Upon identification of the potential missing traffic, in
step 230, the traffic unit 112 evaluates the temporal nature of the
records of the potential missing traffic. In particular, for each
aircraft of the potential missing traffic, the traffic unit 112
determines the elapsed time since the last ADS-B message received,
e.g., based on the time stamp in the most recently stored record
relative to the current time period. If the elapsed time is less
than a predetermined amount of time, the aircraft of the potential
missing traffic may be ignored for the current time period. As
described below, the records of these aircraft may be subsequently
evaluated in further iterations of the method 200 such that the
status of the aircraft may change as time elapses. However, in the
current iteration, if the elapsed time is greater than the
predetermined amount of time, the potential missing traffic is
identified as missing proximate traffic. In effect, step 230,
during consecutive iterations of the method 200, results in a timer
beginning upon identification of potential missing traffic, and
upon the elapsed time reaching a predetermined threshold, the
traffic unit 112 identifies the potential missing traffic as
missing proximate traffic. In one exemplary embodiment, the
threshold may be 20 seconds, although other time periods may be
used.
[0041] In step 235, the traffic unit 112 may evaluate the missing
proximate traffic to identify alert conditions. In particular, the
estimated current location may be evaluated with respect to the
own-ship position, altitude, and track to identify potential
incidents. In one exemplary embodiment, the alert may be based on
the possibility of a conflicting path of the own-ship aircraft with
the missing proximate traffic based on the estimated current
location and other flight parameters of the missing traffic. As
such, depending on the evaluation, the missing proximate traffic
may be characterized as missing proximate traffic that does not
require an alert or missing proximate traffic that does require an
alert. Collectively, these characterizations may be referred to as
missing proximate traffic information. The alert may take any
suitable form, as discussed in greater detail below.
[0042] In step 240, the traffic unit 112 or other component of the
system 100 presents information (e.g., annunciations or warnings)
associated with steps 230 and 235, to the operator. In one
exemplary embodiment, the traffic unit 112 generates display
signals to annunciate the missing traffic information, which will
be described with reference to FIG. 4. Generally, FIG. 4 is a
traffic display 400 similar to the traffic display 300 of FIG. 3.
For example, the traffic display 400 is centered on the own-ship
aircraft, represented by symbol 402, with one or more range rings
404. As shown, the traffic display 400 also includes symbology
(e.g., icons) representing each aircraft that forms the surrounding
traffic 411-413. The traffic 411-413 on the traffic display 400
corresponds to the aircraft traffic for which the messages were
received in the current time period, e.g., similar to the traffic
311-313 of FIG. 3. In the scenario of FIG. 4, aircraft traffic 413
is proximate traffic, while aircraft traffic 411, 412 is
non-proximate traffic, as indicated by the respective icon
symbology, as discussed above.
[0043] The traffic display 400 may provide information regarding
the missing proximate traffic in various ways. In the scenario of
FIG. 4, the missing proximate traffic generally corresponds to the
two aircraft associated with proximate traffic 314, 315 described
above in FIG. 3. In one exemplary embodiment, the missing proximate
traffic may be presented in the form of visual annunciation for
each aircraft of the missing proximate traffic. In particular, the
traffic display 400 may include an area 420 with a text-based
message 424, 425 for each aircraft of the missing proximate
traffic. Each message 424, 425 may include the aircraft
identification, the last reported position, the last reported
altitude, the last reported track, and/or the time elapsed since
the most recent messages from the other aircraft. In the situation
of FIG. 4 relative to FIG. 4, message 424 generally corresponds to
the aircraft associated with proximate traffic 314 in FIG. 3, and
message 425 generally corresponds to the aircraft associated with
proximate traffic 315 in FIG. 3. In further embodiments, audio
annunciation may be alternatively or additionally provided.
[0044] In some situations, the traffic display 400 also includes
missing proximate traffic information in the form of symbology
representing missing proximate traffic. In one exemplary
embodiment, this symbology may be based on the alert condition from
the evaluation of missing proximate traffic in step 235. In other
words, additional symbology on the traffic display 400 may function
as an alert for the alert condition to emphasize potential issues
with the missing proximate traffic.
[0045] In the traffic display 400 of FIG. 4, the alert symbology
may include an icon 415 representing the aircraft of missing
proximate traffic that may conflict with the flight path of the
own-ship aircraft. In the situation of FIG. 4 relative to the
situation in FIG. 3, the aircraft represented by icon 415 in FIG. 4
corresponds to the same aircraft as proximate traffic 315 from FIG.
3, except that the failure to receive traffic information from this
aircraft during the current time period after the predetermined
timing threshold has triggered an alert condition, as discussed
above in steps 225 and 230.
[0046] As shown in FIG. 4, the icon 415 for the missing proximate
traffic may be positioned at the estimated position of aircraft
associated with the missing proximate traffic from step 235. As
previously noted, the estimated position may be based on the most
recently reported position, altitude, track and time. The icon 415
for the missing proximate traffic may be presented in a manner
different to the confirmed traffic 411-413, thereby indicating to
the operator that the position of the missing proximate traffic
icon 415 is estimated. For example, the missing proximate traffic
icon 415 may have different line thicknesses, dynamic appearances
(e.g., blinking), or otherwise highlighted or diminished. In the
depicted exemplary embodiment, the missing proximate traffic icon
415 is depicted as a diamond shape.
[0047] Additionally, the symbology for the missing proximate
traffic may include indications regarding the level of uncertainty
with the estimation of the position of the missing proximate
traffic icon 415. For example, a zone or range area outline 435
surrounding the icon 415 may be provided to give the operator of
the own-ship additional information about the possible location of
the missing proximate traffic.
[0048] The zone (e.g., outline 435) associated with the estimated
position may be sized according to the level of uncertainty. For
example, if no confirmed location of the missing proximate traffic
has been received in a relatively brief amount of time, the zone
may be smaller than if no confirmed location has been received in a
relatively large amount of time. As described below, the zone may
be omitted or resized if updated information about the position is
received from other sources. As such, the symbology presented for
the missing proximate traffic (e.g., 415, 435) on traffic display
400 improves situational awareness by providing the operator an
estimate of the relative location of any aircraft that may be in
the area, even though the aircraft may not be broadcasting ADS-B
messages.
[0049] Returning to FIG. 2, the method 200 proceeds to step 245 in
which the traffic unit 112 or other component may initiate a
message to air traffic control. In particular, the message to air
traffic control may include information regarding the most recent
ADS-B message from the missing proximate traffic. In one exemplary
embodiment, the message to air traffic control may include a
request for additional information about the missing proximate
traffic. In some situations, air traffic control may have
additional information regarding the status of the missing
proximate traffic. As such, in response, the ATC may provide
additional information about the current or more recent location,
altitude, and/or track of the missing proximate traffic. In one
exemplary embodiment, these messages may be transmitted via the
communication unit 160 and/or systems such as datalink or aircraft
communications addressing and reporting systems (ACARS), CPDLC, or
voice messages.
[0050] Referring to FIG. 4, in one exemplary embodiment, the
traffic display 400 may include symbology to initiate a request for
additional information from air traffic control. For example, the
area 420 with the text-based messages 424, 425 may further include
symbols 444, 445 to initiate the information request. As such, upon
operator selection of the symbol 444, 445, a message is generating
requesting updated information for the respective aircraft. In
other embodiments, such messages may be automatically generated and
sent.
[0051] Returning to FIG. 2, in step 250 updated information from
air traffic control may be received and evaluated. For example,
such information may include an updated position for one or more
aircraft of the missing proximate traffic.
[0052] In step 255, the updated information from air traffic
control may be presented to the operator. Reference is briefly made
to FIG. 5, which corresponds to a traffic display 500 that has been
updated relative to the traffic display 400 in FIG. 4. As in FIG.
4, FIG. 5 depicts an own-ship aircraft 502, range ring 504,
confirmed non-proximate traffic 511, 512, and confirmed proximate
traffic 513. As above, the traffic 511, 512, 513 is based on
messages received from the associated aircraft in the current time
period.
[0053] Relative to FIG. 3, the aircraft associated with missing
proximate traffic 314, 315 is still missing, e.g., based on not
receiving position information from the aircraft. As such, the
visual annunciation in area 520 with messages 524, 525
corresponding to each aircraft is presented with the appropriate
information. Relative to FIG. 4, however, the traffic display 500
of FIG. 5 is updated to reflect the additional information received
by the traffic unit 112. For example, in the situation of FIG. 5,
air traffic control provided updated information associated with
missing proximate traffic 514 (e.g. corresponding to proximate
traffic 314 of FIG. 3) and missing proximate traffic 515 (e.g.
corresponding to proximate traffic 315 of FIG. 3 and missing
proximate traffic 415 of FIG. 4). The visual display 500 may
present the updated missing proximate traffic 514, 515 in a manner
that distinguishes it over confirmed proximate and non-proximate
traffic 511-513. For example, each of the updated missing proximate
traffic 514, 515 is depicted with a diamond shape.
[0054] The updated missing proximate traffic 514, 515 may also be
presented in a manner that indicates the nature of the traffic. For
example, the icon for traffic 514 has a hatched or partially solid
interior, while the icon for traffic 515 is solid. The solid nature
of traffic 515 reflects the alert condition discussed above with
reference to step 235. However, relative to the traffic display 400
of FIG. 4, the zone 435 has been removed based on the updated
information from the air traffic control to indicate the reduced
level of uncertainty regarding the position of traffic 515. As also
shown in FIG. 5, operator may request further updated information
from air traffic control with symbols 544, 545 in area 520.
[0055] In step 260, the traffic unit 112 may initiate the
collection of additional information about the missing proximate
traffic from other components or systems of the aircraft. For
example, as noted above, the navigation system 130, flight
management system 140, and/or sensors 150 may include various types
of sensors that are used for a number of navigation and control
functions, such as primary radar or EVS sensors. For example, such
sensors may collect information in the estimated area of the
missing proximate traffic in order to identify updated
characteristics of the aircraft without the ADS-B messages. In one
exemplary embodiment, step 260 may be omitted if air traffic
control provided updated information for the missing proximate
traffic in step 250. In other words, in one exemplary embodiment,
step 260 may be initiated upon failure to receive updated
information from air traffic control. In step 265, if additional or
updated information is received from other aircraft system, the
traffic display may be further updated, e.g., by updating the
symbology representing the missing proximate traffic, in a manner
similar to that depicted in FIG. 5 or other manner to indicate the
source of the updated information (e.g., from air traffic control
or sensors).
[0056] Although depicted with respect to traffic displays 300, 400,
500, other display formats may be provided. For example, aspects of
exemplary embodiments may be implemented in one or more of a
multi-function display (MFD), a three-dimensional MFD, a primary
flight display (PFD), a synthetic vision system (SVS) display, a
vertical situation display (VSD), a horizontal situation indicator
(HSI), a traffic awareness and avoidance system (TAAS) display,
and/or a traffic alert and collision avoidance system (TCAS).
[0057] Accordingly, the exemplary embodiments discussed above
provide improved monitoring, evaluation, and display of aircraft
traffic. In particular, exemplary embodiments function to identify,
monitor, evaluate, and display missing aircraft traffic by
identifying missing ADS-B messages. As such, missing aircraft
traffic information may be presented to the operator for further
consideration, including displays, alerts, and/or messages to air
traffic control. Further, estimates and/or updated information
about the missing aircraft traffic information may be presented to
the user to improve situational awareness and safety. In one
exemplary embodiment, such information may be presented in the
context of a familiar display, such as a traffic display, thereby
providing a more convenient and/or salient presentation for easy
recognition and evaluation. As such, the operator may provide the
proper amount of attention to the missing aircraft traffic, thereby
reducing workload and navigation and control errors, improving
performance consistency, and increasing flight safety.
[0058] The steps of a method or algorithm described in connection
with the embodiments disclosed herein may be embodied directly in
hardware, in a software module stored in any suitable computer
readable storage medium and executed by a processor, or in a
combination thereof. For the sake of brevity, conventional
techniques related to graphics and image processing, navigation,
flight planning, aircraft controls, aircraft data communication
systems, and other functional aspects of certain systems and
subsystems (and the individual operating components thereof) may
not be described in detail herein.
[0059] While at least one exemplary embodiment has been presented
in the foregoing detailed description of the invention, it should
be appreciated that a vast number of variations exist. It should
also be appreciated that the exemplary embodiment or exemplary
embodiments are only examples, and are not intended to limit the
scope, applicability, or configuration of the invention in any way.
Rather, the foregoing detailed description will provide those
skilled in the art with a convenient road map for implementing an
exemplary embodiment of the invention. It being understood that
various changes may be made in the function and arrangement of
elements described in an exemplary embodiment without departing
from the scope of the invention as set forth in the appended
claims.
* * * * *