REACT
REACT Project: Preliminary Set
of Requirements for an AIDL
Javier López Leonés • Boeing Research and Technology Europe
Seville, Spain • 24-25 June 2008
Trajectory Related Information Exchange
REACT Workshop
Seville, Spain 24th- 25th June 2008
Trajectory Prediction (e.g., flight management system)
Airborne TP
Flight
Intent
Flight Intent
Information
Flight
Intent
Intent
Generation
Infrastructure
(1)
Data COM Infrastructure
Intent
Generation
Infrastructure
(2)
Aircraft
Intent
Trajectory
Computation
Infrastructure
(1)
Predicted trajectory
information
Aircraft Intent
information
Aircraft
Intent
Airborne
Predicted
Trajectory
Trajectory
Computation
Infrastructure
(2)
Ground
Predicted
Trajectory
Ground TP
TP PROCESS 2 (e.g., arrival manager)
REACT
2
Trajectory Related Information Exchange
REACT Workshop
Seville, Spain 24th- 25th June 2008
Trajectory Prediction (e.g., flight management system)
Airborne TP
Flight
Intent
Flight Intent
Information
Flight
Intent
Intent
Generation
Infrastructure
(1)
Data COM Infrastructure
Intent
Generation
Infrastructure
(2)
Aircraft
Intent
Trajectory
Computation
Infrastructure
(1)
Predicted trajectory
information
Aircraft Intent
information
Aircraft
Intent
Airborne
Predicted
Trajectory
Trajectory
Computation
Infrastructure
(2)
Ground
Predicted
Trajectory
Ground TP
TP PROCESS 2 (e.g., arrival manager)
REACT
3
REACT Scope
REACT Workshop
Seville, Spain 24th- 25th June 2008
Trajectory Prediction
Flight
Intent
Intent
Generation
Infrastructure
Aircraft
Intent
Trajectory
Computation
Infrastructure
Airborne
Predicted
Trajectory
REACT
4
What is the AIDL?
REACT Workshop
Seville, Spain 24th- 25th June 2008
• The Aircraft Intent Description Language (AIDL) is a formal language designed to
describe aircraft intent information in a rigorous but flexible manner
• AIDL comprises of an alphabet and a grammar (lexical and syntactical)
REACT
5
What is the AIDL?
REACT Workshop
Seville, Spain 24th- 25th June 2008
AIDL
Trajectory Prediction (Air or Ground)
Trajectory Predictor (TP)
Intent
Generation
Infrastructure
Flight
Intent
Aircraft
Intent
Trajectory
Computation
Infrastructure
Predicted
Trajectory
Initial
Conditions
?
Airborne
Automation
System
Flight
Plan
Tactical
Amendments
to Flight Plan
Actual aircraft state
(position, speed,
weight…)
Flight
Commands &
Guidance Modes
Actual
Trajectory
Pilot
Aircraft
Real World
REACT
AT or ABOVE FL290
Environmental
Conditions
6
What is the AIDL?
REACT Workshop
Seville, Spain 24th- 25th June 2008
• The Aircraft Intent Description Language (AIDL) is a formal language designed
to describe aircraft intent information in a rigorous but flexible manner
• AIDL comprises of an alphabet and a grammar (lexical and syntactical)
• AIDL alphabet contains a set of instructions, which define all the possible ways
in which different TPs model flight commands and guidance modes in ATM
• Lexical grammar contains a set of rules (lexicon) to define valid simultaneous
combination of the instructions to express elemental behaviors of the aircraft
(operations)
• Syntactical grammar contains a set of rules (syntax) to define valid sequential
combination of instructions to express the sequence of operations that give
rise to the trajectory
REACT
7
REACT Objectives
REACT Workshop
Seville, Spain 24th- 25th June 2008
• Eliciting requirements for a common AIDL that can support trajectory
synchronization in future Trajectory-Based Operations (TBO)
• This common AIDL has to
– be application independent
– serve to encode aircraft intent information for both air or ground trajectory-based
automation systems
– support air-air, air-ground and ground-ground interoperability
– cover any level of detail demanded by trajectory-based applications
– serve to express the input to any trajectory computation infrastructure in ATM
• The AIDL shall contain formal / mathematical structures to define all the possible
ways in which different TPs model flight commands / guidance modes and standard
procedures in ATM ( the instructions )
REACT
8
REACT so far…
REACT Workshop
Seville, Spain 24th- 25th June 2008
• Elicitation of requirements for a common AIDL :
– Variety of stakeholders approached: ATM industry, FMS manufacturers, airlines and
developers of automation tools for future trajectory-based concepts
– Requirements on how each of these stakeholders internally model aircraft intent
information in their systems: specific application-driven Aircraft Intent Description
Model (AIDM)
– Understand the commonalities among these systems in terms of aircraft intent
description
• The AIDL shall comply with all the requirements identified during the elicitation
process: AIDL is the superset of the AIDMs identified
REACT
9
Contributors to REACT
REACT Workshop
ATM INDUSTRY
–
FDPS
–
–
–
–
–
–
ATM AUTOMATION
–
ASA - Flight Plan Conflict Function
ASA - MAESTRO AMAN
NATS - iFACTS
BARCO - OSYRIS AMAN
Flight Planning Tools
–
–
–
–
EMIRATES - Flight Planning
BRITISH AIRWAYS - Flight Planning
QANTAS - Flight Planning
VIRGIN BLUE - Flight Planning
REACT
Future Automation
–
–
–
–
–
ATM Tools
–
–
–
–
–
INDRA - FDPS TP
THALES - EUROCAT-E TP
SELEX SI – CoFlight
ASA - EUROCAT-X TP
Lockheed Martin - ERAM
Seville, Spain 24th- 25th June 2008
EUROCONTROL - TMA 2010+
LVNL - SARA TP
NASA AMES, L3 COMMUNICATIONS - CTAS TP
NASA LaRC - 4D FMS
Advanced APMs
–
BOEING R&TE, Eurocontrol - BADA 4.0
FMS INDUSTRY
–
FMS TP and Guidance
–
–
–
GE AVIATION – FMS TP
HONEYWELL – FMS TP
Specific FMS Functions
–
–
GE AVIATION - Altitude Planning
GE AVIATION - FMS RTA
EUROCONTROL
–
TMA 2010+, FASTI, Datalink User Group, Flight
Object Group, CFMU, Surface Movement, Military
10
Elicitation Process Methodology (I)
REACT Workshop
Seville, Spain 24th- 25th June 2008
Trajectory Prediction
Flight
Intent
REACT
Intent
Generation
Infrastructure
Aircraft
Intent
Trajectory
Computation
Infrastructure
Airborne
Predicted
Trajectory
Flow-down aircraft intent generation capabilities
Flow-up trajectory computation capabilities
11
Elicitation Process Methodology (II) – Top Down
REACT Workshop
Seville, Spain 24th- 25th June 2008
Trajectory Prediction
Flight
Intent
REACT
Intent
Generation
Infrastructure
Aircraft
Intent
Trajectory
Computation
Infrastructure
Airborne
Predicted
Trajectory
Flow-down aircraft intent generation capabilities
Flow-up trajectory computation capabilities
12
Elicitation Process Methodology (II) – Top Down
REACT Workshop
Seville, Spain 24th- 25th June 2008
Aircraft Intent Generation Process
•Route Conversion
•Path Initialization
•Constraint Specification
•Intent Modeling
Intent
Generation
Infrastructure
Operational Context Model (OCM)
•Airspace configuration (e.g.
airways, fix and airport definitions,
sector boundaries,…)
User Preferences Model (UPM)
REACT
•Aircraft performance
characteristics, pilot models, and
company preferences
13
Elicitation Process Methodology (III) – Bottom Up
REACT Workshop
Seville, Spain 24th- 25th June 2008
Trajectory Prediction
Flight
Intent
REACT
Intent
Generation
Infrastructure
Aircraft
Intent
Trajectory
Computation
Infrastructure
Airborne
Predicted
Trajectory
Flow-down aircraft intent generation capabilities
Flow-up trajectory computation capabilities
14
Elicitation Process Methodology (III) – Bottom Up
REACT Workshop
Seville, Spain 24th- 25th June 2008
Trajectory Engine (TE)
•Lateral and vertical path computation
•Equations of Motion
•…
Earth Model (EM)
•Wind model
•Reference systems
Trajectory
Computation
Infrastructure
•…
Aircraft Performance Model (APM)
•Type of APM (e.g. kinematical)
•Input needed
REACT
•…
15
Elicitation Process Methodology (IV) –Requirements Derivation
REACT Workshop
Seville, Spain 24th- 25th June 2008
AIDM1
AIDM2
AIDM3
AIDMn
Elicitation
Reports
Requirements
consolidation
process
AIDL structural
requirements
AIDMs
Derivation
REACT
16
Example: FDPS -X
REACT Workshop
•
Seville, Spain 24th- 25th June 2008
Which aspects of the aircraft motion can be affected by the AIDM in
place (speed, configuration, vertical and lateral movement, throttle
control)?
Speed, vertical and lateral profiles.
•
Which aspects are not covered but are needed for the computation
of the trajectory (e.g. cost index, procedures for turnings,
configuration or throttle input)?
Configuration and throttle decisions are embedded in the APM.
REACT
17
Example: FDPS -X
REACT Workshop
•
Seville, Spain 24th- 25th June 2008
How can each of those aspects be modified (e.g. vertical motion
can be affected by controlling the vertical speed, the path angle or
the altitude; lateral path using the bank angle and constant bearing
segments)?
The vertical and longitudinal motion is defined using constant airspeed
segment (conventional air mass climb/descents ISA/Mach). In climb/descent,
the corresponding values of ROC/ROD for the aircraft type at hand are
provided by the APM (BADA tables). These values are obtained assuming a
constant speed (IAS or Mach) and maximum climb/idle rating for
climbs/descents, respectively. The Flight Level/altitude profile can contain
constant Flight Level/altitude segments but no other control over the path
angle is available. The lateral path is defined using both the heading
segments and curves over the Earth’s surface, such as great circles joining
two waypoints. Bank angle is not considered (turn rate is used to model
turns).
REACT
18
Example: FDPS -X
REACT Workshop
•
Seville, Spain 24th- 25th June 2008
How many types of speed, altitude, path angle, vertical speed,
throttle input, etc can be used (e.g. speed can only be Mach or CAS)
Speeds: Ground speed (absolute aircraft speed measured with respect to the
ground), TAS in knots or Mach, CAS
Vertical Speed: Pressure ROC/ROD
Altitude: Pressure altitude
Course: Magnetic Heading
REACT
19
Example: AIDM Implicit DerivationFDPS -X
REACT Workshop
Seville, Spain 24th- 25th June 2008
INSTRUCTIONS REQUIRED
Profile
Speed
Code
Airspeed
Altitude
Specifier
Law
CAS
Constant
IAS
Constant
Mach
Constant
TAS
Constant
Ground Speed
Constant
Pressure
Constant
Vertical
Vertical Speed
ROC/ROD
Given by the APM
Throttle
Lateral
REACT
Configuration
Comments
These values are obtained assuming a
constant speed (IAS or Mach) and
maximum climb/idle rating for
climbs/descents, respectively.
Modified within the APM
Track
Great Circle
Great circle law
Hold Heading
Magnetic
Heading
Constant
Turn
Magnetic
Heading
Linear Law
Turns are modelled as a manoeuvre
at constant turn rate (fixed in
general)
Modified within the APM
20
Preliminary Results (I)
REACT Workshop
Seville, Spain 24th- 25th June 2008
• An AIDL shall model FIVE behavioural aspects of the aircraft motion (AIDL
instructions)
– Lateral profile: geometrical path, course, bank angle
– Vertical profile: altitude, vertical speed, path angle
– Speed profile: airspeed, horizontal speed
– Throttle profile: engine ratings
– Configuration profile: high lift devices, speed brakes, landing gear
• An AIDL shall have formal mechanisms to indicate how each of these aspects are
specified (Instruction Specifier)
– Airspeed can be CAS, Mach, etc;
– Engine ratings can be maximum climb, idle, etc
– Course can be bearing or heading, magnetic or true, etc;
– …
REACT
21
Preliminary Results (II) :AIDL Primitives & Grammar Rules
REACT Workshop
Seville, Spain 24th- 25th June 2008
Motion Profiles
Speed
AIDL Alphabet
SG
Set
Law/Track
Hold
Open loop input
#
Keyword
HSG
SL
HS
Instruction
1
SL
Speed Law
2
HS
Hold Speed
3
HSL
Horizontal Speed Law
4
5
HHS
VSL
Hold Horizontal Speed
Vertical Speed Law
6
HVS
Hold Vertical Speed
7
SPA
Set Path Angle
8
PAL
Path Angle Law
9
HPA
Hold Path Angle
10
OLPA
Open Loop Path Angle
Vertical
VSG
HSL
HHS
Target
vTAS
vTAScosγTAS
vTASsinγTAS
γTAS
PAG
Propulsive
AG
SPA
PAL
HPA
OLPA
VSL
HVS
Configuration Profiles
VPG
AL
HA
TC
Lateral
LDC
ST
TL
HT
OLT
TVP
#
Keyword
Instruction
11
AL
Altitude Law
12
HA
Hold Altitude
13
14
TVP
ST
Track Vertical Path
Set Throttle
15
TL
Throttle Law
16
HT
Hold Throttle
17
18
OLT
SBA
Open Loop Throttle
Set Bank Angle
19
BAL
Bank Angle Law
20
HBA
Hold Bank Angle
21
OLBA
Open Loop Bank Angle
22
CL
Course Law
LDG
SBA
BAL
HBA
OLBA
Target
h
λ, φ, h
δT
μTAS
LPG
CL
HC
THP
HLC
SBC
SHL
HLL
HHL
LGC
SSB
SBL
HSB
OLSB
SLG
HLG
#
Keyword
Instruction
Target
23
HC
Hold Course
χTAS
24
THP
Track Horizontal Path
λ, φ
25
SHL
Seth High Lift devices
26
HLL
High Lift devices Law
27
HHL
Hold High Lift devices
28
SSB
Set Speed Brakes
29
SBL
Speed Brakes Law
30
HSB
Hold Speed Brakes
31
OLSB
Open Loop Speed Brakes
32
SLG
Set Landing Gear
33
HLG
Hold Landing Gear
δHL
δSB
δLG
χTAS
AIDL Lexicon
AIDL Syntax
•
6 instructions, each from a different group
•
Lateral instructions can only be followed by lateral instructions
•
Of the 6, 3 must belong to the motion profiles and 3 to the configuration profiles
•
•
The 3 motion instructions must belong to different motion profiles
Instructions from the configuration groups can only be followed
by instructions from the same group
•
Of the 3 motion instructions, 1 must come from the lateral profile
•
Instructions from vertical, speed and propulsive profiles can only
be followed by instructions of the those profiles
REACT
22
Preliminary Results (III)
REACT Workshop
Seville, Spain 24th- 25th June 2008
HS (CAS)
 Instruction: Hold Speed
 Specifier: CAS
 Constraint: Constant law of 280Knots
CAS=280
HC (GEO,MAG)
 Instruction: Hold Course
 Specifier: GEO,MAG
 Constraint: Constant law of 175º
Magnetic Bearing = 175
REACT
23
Example: FDPS -X
REACT Workshop
•
Seville, Spain 24th- 25th June 2008
How do the switching between modes or instructions take place
(e.g. they capture a certain type of condition)? Can they be
customizable (e.g. user-defined relation between altitude and speed
to end the climb phase)? Is it possible to define multiple conditions
(e.g. AND and OR logic: finish climb when such speed is reached
OR such altitude is reached; finish climbing when such speed is
reached AND such altitude is reached)
–
The AIDM used by the FDPS -X TP considers multiple constraints in the same
point (AND logic) and the possibility of defining OR-type combinations (e.g.
whichever comes first or whichever comes last) to activate / deactivate the
instructions .
REACT
24
Preliminary Results (IV)
REACT Workshop
•
Seville, Spain 24th- 25th June 2008
An AIDL shall contain mechanisms to indicate the conditions for the
changes in the aircraft behaviour (Instructions Triggers)
– Triggers shall support different types of conditions for the
activation/deactivation of the instructions
– Triggers shall support the specification of multiple conditions.
– Triggers shall permit the creation of mode switching logics, this is a
“conditioned aircraft intent”
REACT
25
Preliminary Results (V): AIDL Expressivity Mechanisms
REACT Workshop
Seville, Spain 24th- 25th June 2008
Trigger conditions control instructions’ execution interval
CAS=200knots
Pilot event
t =t0
HS (MACH=0.65)
h=4500 ft AND r<200 NM
OR
h=2500 ft
h=4500ft
OR
r=200NM
M=0.78
f(λ,φ) = 0
HA (PRE=22000 ft)
r>200 NM
VSL (ROC=200ft/min)
h=2500 ft
Bearing=210º
HS (CAS)
HA (PRE)
HS (CAS)
HPA (GEO)
REACT
26
AIDL Example: Descent profile using AIDL instructions
Longitudinal
Seville, Spain 24th- 25th June 2008
TOD
A
FL320
M .88
CA
M .78
AoA 4500ft
AoB 180 KCAS
? KCAS
280
AoB 280 KCAS
N370945.72
W0032438.01
Horizontal
AIRCRAFT TRAJECTORY
REACT Workshop
180 KCAS
R?
Time
Pilot event
Speed Profile
h=4500ft
280KCAS
HS
HS
HS
H
S
AIRCRAFT INTENT
M=0.78
Vertical Profile
HA
HS
HS
HS
HA
HS
HA
HA
180KCAS
TL
Propulsive Profile
TL
TL
TL
TL
Capture of
target bank
Roll-in anticipation
?
TL
Roll-in anticipation
?
d
TL
TL
d
Capture of
target bank
Lateral Profile
THP
THP
THP
THP
SBA
HBA
SBA
THP
THP
THP
REACT
OPERATIONS
OP#1
OP#2
OP#3
OP#4
OP#5
OP#6
OP#7
OP#8
OP#9
OP#10
27
Future steps …
REACT Workshop
Seville, Spain 24th- 25th June 2008
• Eliciting requirements for a common AIDL that can support trajectory
synchronization in future Trajectory-Based Operations (TBO)
• Development of a AIDL prototype that fulfill those requirements
• Evaluation of the use of such an AIDL for trajectory synchronization comparing with
other types of trajectory related information (e.g., flight intent, predicted trajectory,..)
• Development of an standard, based on the AIDL prototype, for the exchange of
aircraft intent information
REACT
28
Thank you!
REACT Workshop
Seville, Spain 24th- 25th June 2008
Q&A
REACT
29