Seville, Spain 24-25 June 2008 REACT Project: Preliminary Set of Requirements for an AIDL Javier López Leonés Boeing Research and Technology Europe

Seville, Spain • 24-25 June 2008

REACT Project: Preliminary Set of Requirements for an

AIDLJavier López Leonés • Boeing Research and Technology Europe

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REACT Workshop Seville, Spain 24th- 25th June 2008

Trajectory Related Information Exchange

Data COM Infrastructure Predicted trajectory information

Flight Intent

AirbornePredicted Trajectory

TP PROCESS 2 (e.g., arrival manager)

Flight Intent

GroundPredicted Trajectory

Trajectory

Computation

Infrastructure

(1)

Aircraft Intent

Intent

Generation

Infrastructure

(1)

Airborne TP

Trajectory

Computation

Infrastructure

(2)

Aircraft Intent

Intent

Generation

Infrastructure

(2)

Ground TP

Aircraft Intent information

Flight Intent Information

Trajectory Prediction (e.g., flight management system)

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Trajectory Related Information Exchange

Data COM Infrastructure Predicted trajectory information

Flight Intent


TP PROCESS 2 (e.g., arrival manager)

Flight Intent

GroundPredicted Trajectory

Trajectory

Computation

Infrastructure

(1)

Aircraft Intent

Intent

Generation

Infrastructure

(1)

Airborne TP

Trajectory

Computation

Infrastructure

(2)

Aircraft Intent

Intent

Generation

Infrastructure

(2)

Ground TP

Aircraft Intent information

Flight Intent Information

Trajectory Prediction (e.g., flight management system)

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REACT Scope

Flight Intent


Trajectory

Computation

Infrastructure

Aircraft Intent

Intent

Generation

Infrastructure

Trajectory Prediction

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• 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)

What is the AIDL?

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Actual aircraft state (position, speed, weight…)

What is the AIDL?

Environmental Conditions

Pilot

Real World

Trajectory Prediction (Air or Ground)

Flight Commands & Guidance Modes

Flight Intent

Flight Plan

Tactical Amendments to Flight Plan

Airborne Automation System

Actual Trajectory

?

Aircraft

Predicted Trajectory

Trajectory

Computation

Infrastructure

Aircraft Intent

Intent

Generation

Infrastructure

Initial Conditions

Trajectory Predictor (TP)

AT or ABOVE FL290

AIDL

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• 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

What is the AIDL?

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REACT Objectives

• 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 )

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REACT so far…

• 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

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Contributors to REACT

ATM INDUSTRY– FDPS

– INDRA - FDPS TP– THALES - EUROCAT-E TP– SELEX SI – CoFlight – ASA - EUROCAT-X TP– Lockheed Martin - ERAM

– ATM Tools– 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

ATM AUTOMATION– Future Automation

– 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

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Elicitation Process Methodology (I)

Flight Intent


Trajectory

Computation

Infrastructure

Aircraft Intent

Intent

Generation

Infrastructure


Flow-down aircraft intent generation capabilities

Flow-up trajectory computation capabilities

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Elicitation Process Methodology (II) – Top Down

Flight Intent


Trajectory

Computation

Infrastructure

Aircraft Intent

Intent

Generation

Infrastructure




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Elicitation Process Methodology (II) – Top Down

Intent

Generation

Infrastructure

User Preferences Model (UPM)

•Aircraft performance characteristics, pilot models, and company preferences

Operational Context Model (OCM)

•Airspace configuration (e.g. airways, fix and airport definitions, sector boundaries,…)

Aircraft Intent Generation Process

•Route Conversion

•Path Initialization

•Constraint Specification

•Intent Modeling

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Elicitation Process Methodology (III) – Bottom Up

Flight Intent


Trajectory

Computation

Infrastructure

Aircraft Intent

Intent

Generation

Infrastructure




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Elicitation Process Methodology (III) – Bottom Up

Aircraft Performance Model (APM)

•Type of APM (e.g. kinematical)

•Input needed

•…

Trajectory Engine (TE)

•Lateral and vertical path computation

•Equations of Motion

•…

Earth Model (EM)

•Wind model

•Reference systems

•…

Trajectory

Computation

Infrastructure

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Elicitation Process Methodology (IV) –Requirements Derivation

Elicitation Reports

AIDMs Derivation

AIDM1

AIDM2

AIDM3

AIDMn

Requirements consolidation

process

AIDL structural requirements

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Example: FDPS -X

• 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.

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Example: FDPS -X

• 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).

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• 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

Example: FDPS -X

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INSTRUCTIONS REQUIRED

Profile Code Specifier Law Comments

Speed Airspeed

CAS Constant

IAS Constant

Mach Constant

TAS Constant

Ground Speed

Constant

Vertical

Altitude Pressure Constant

Vertical Speed

ROC/RODGiven by the

APM

These values are obtained assuming a constant speed (IAS or Mach) and maximum climb/idle rating for climbs/descents, respectively.

Throttle Modified within the APM

Lateral

Track Great CircleGreat circle

law

Hold Heading

Magnetic Heading

Constant

TurnMagnetic Heading

Linear LawTurns are modelled as a manoeuvre at constant turn rate (fixed in general)

Configuration

Modified within the APM

Example: AIDM Implicit DerivationFDPS -X

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Preliminary Results (I)

• 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;

– …

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Preliminary Results (II) :AIDL Primitives & Grammar Rules

Set

Law/TrackHold

Open loop input

LateralVerticalSpeed Propulsive

Motion Profiles Configuration Profiles

AIDL Alphabet LDCTCSG PAG LDGAGHSG VSG LPGVPG HLC SBC LGC

SLHS

CLHSLHHS

SBA

BALHBA

OLBA

HCTHPAL

HA

SPA

PALHPA

TVPVSLHVS

ST

TLHT

OLT

SHL

HLL

SSB

SBL

SLG

OLPA

HHL HSB

OLSB

HLG

# Keyword Instruction Target

1 SL Speed LawvTAS

2 HS Hold Speed

3 HSL Horizontal Speed LawvTAScosγTAS

4 HHS Hold Horizontal Speed


11 AL Altitude Lawh

12 HA Hold Altitude

13 TVP Track Vertical Path λ, φ, h


23 HC Hold Course χTAS

24 THP Track Horizontal Path λ, φ

5 VSL Vertical Speed LawvTASsinγTAS6 HVS Hold Vertical Speed

7 SPA Set Path Angle

γTAS

8 PAL Path Angle Law

9 HPA Hold Path Angle

10 OLPA Open Loop Path Angle

14 ST Set Throttle

δT

15 TL Throttle Law

16 HT Hold Throttle

17 OLT Open Loop Throttle

25 SHL Seth High Lift devices

δHL26 HLL High Lift devices Law

27 HHL Hold High Lift devices

28 SSB Set Speed Brakes

δSB

29 SBL Speed Brakes Law

30 HSB Hold Speed Brakes

31 OLSB Open Loop Speed Brakes

32 SLG Set Landing GearδLG

33 HLG Hold Landing Gear

18 SBA Set Bank Angle

μTAS

19 BAL Bank Angle Law

20 HBA Hold Bank Angle

21 OLBA Open Loop Bank Angle

22 CL Course Law χTAS

AIDL Lexicon

• 6 instructions, each from a different group

• 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

• Of the 3 motion instructions, 1 must come from the lateral profile

AIDL Syntax

• Lateral instructions can only be followed by lateral instructions

• Instructions from the configuration groups can only be followed by instructions from the same group

• Instructions from vertical, speed and propulsive profiles can only be followed by instructions of the those profiles

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Preliminary Results (III)

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

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Example: FDPS -X

• 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 .

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Preliminary Results (IV)

• 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”

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Preliminary Results (V): AIDL Expressivity Mechanisms

HA (PRE=22000 ft)

M=0.78

HS (MACH=0.65)

Pilot event t =t0

VSL (ROC=200ft/min)

h=4500ftOR

r=200NM

Trigger conditions control instructions’ execution interval

f(λ,φ) = 0

CAS=200knots

HA (PRE)

r>200 NM

HS (CAS)

h=4500 ft AND r<200 NMOR

h=2500 ft

HS (CAS) HPA (GEO)

Bearing=210ºh=2500 ft

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REACT Workshop Seville, Spain 24th- 25th June 2008AIDL Example: Descent profile using AIDL instructions

Lo

ng

itu

din

alH

ori

zon

tal

AIR

CR

AF

T T

RA

JEC

TO

RY

Time

CATOD

R?075

FL320M .78M .88

? KCAS

110

N370945.72W0032438.01

THP

HA

AIR

CR

AF

T IN

TE

NT

Vertical Profile

Propulsive Profile

Speed Profile

OPERATIONS

HS HS HS HS

TL

Lateral Profile SBA HBA SBA

OP#1 OP#2 OP#3 OP#4 OP#5 OP#6 OP#7 OP#8 OP#9 OP#10

HA

TL

THP THP

HS HS

HS

TL

HS

THP THP

HA HA

THP

TL TL TL TL TL

THP

AoB 280 KCAS

AoA 4500ftAoB 180 KCAS

A

280 KCAS

180 KCAS

M=0.78

Pilot event

?

Roll-in anticipation

d

Capture of target bank

h=4500ft280KCAS

d

Capture of target bank

180KCAS

?

Roll-in anticipation

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Future steps …

• 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

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Thank you!

Q&A

Documents

Seville, Spain 24-25 June 2008 REACT Project: Preliminary Set of Requirements for an AIDL Javier López Leonés Boeing Research and Technology Europe