NASA Technical Reports Server (NTRS) 20170009881: Flight Control of Flexible Aircraft

2.6 MB·English

by  NASA Technical Reports Server (NTRS)

National Aeronautics and Space Administration
Flight Control of Flexible Aircraft
Dr. Nhan Nguyen
Technical Group Lead
Advanced Control and Evolvable Systems (ACES) Group
Intelligent Systems Division
NASA Ames Research Center
Moffett Field, CA

NESC GNC Meeting at NASA ARC
January 25, 2017
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Outline


•  Introduction
•  Performance Adaptive Aeroelastic Wing
•  Aeroservoelasticity Modeling of Flexible Aircraft
•  Multi-Objective Flight Control
–  Real-Time Drag Minimization
–  Gust / Maneuver Load Alleviation
–  Adaptive Flutter Suppression
•  X-56A Collaboration
•  Other Collaborations
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Advanced Control and Evolvable Systems Group
•  Advanced Control and Evolvable Systems (ACES) Group within the
Intelligent Systems Division (code TI) has 21 researchers, 13 with Ph.D.
•  Conduct GNC research and multidisciplinary fixed-wing vehicle dynamic
modeling and simulations
•  More than 90% research supports aeronautics with some space-related
GNC
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Introduction


•  Composite wing technology in modern passenger aircraft affords weight
reduction but also causes increased wing flexibility
Composite Airframe
N+3 Aircraft
High-Aspect Ratio Truss-Braced Wing
Boeing 787
Copyright © Boeing
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Impact on Aerodynamics
•  Increased wing deflection impacts optimal span load at off-design, causing
increase in drag

Increased drag leads to
increased fuel consumption
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Impact on Flight Load, Stability and Control
•  Increased wing flexibility causes reduced flutter margin, aeroservoelastic
interactions with dynamics and control, and increased gust response

High Aspect Ratio Low
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Performance Adaptive Aeroelastic Wing Research


•  Multidisciplinary design analysis optimization (MDAO) capabilities for
development of advanced adaptive wing technology concepts
Mul<-Fidelity Modeling ASE – Flight Dynamics Control Effectors
• Mul6-fidelity aero modeling (Cart3D, • Coupled ASE – rigid aircraL flight • VCCTEF / con6nuous leading
Overflow, Lava, Vorlax, Vspaero) dynamics edge slat
• Coupled FEM (Beam3D, NASTRAN) with • Gust modeling • Distributed control surfaces
aero codes • Actuator dynamics of ASE control • Other novel concept
• Aeroelas6city / Aeroservoelas6city (ASE) effectors

Mul<disciplinary Op<miza<on ASE Flight Control Performance Analysis
• Aerodynamic design op6miza6on for • ASE control (fluGer suppression, • Design trade-study
drag reduc6on load allevia6on) • Mission analysis / trajectory
• MDO for drag minimiza6on, load • mul6-objec6ve flight control op6miza6on to minimize fuel
allevia6on, and ac6ve ASE control • Real-6me drag op6miza6on burn
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Performance Adaptive Aeroelastic Wing


•  Variable Camber Continuous Trailing Edge Flap (VCCTEF) developed by
NASA and Boeing Research & Technology as adaptive wing control
technology for drag reduction
Multi-Segment Variable Camber
SMA and EMA Hinge Line Actuation
Individual Flap Deflection for
Spanwise Lift Optimization
Conformal Mold Line Material
for Gap Covering to Eliminate
Flap Noise and Reduce Drag
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Flexible Wing High-Aspect Ratio Transport Models
•  Flexible conventional transport and next-generation Truss Brace Wing
NASA Generic
Truss-Braced Wing
Transport Model
Aircraft (TBW)
(GTM)
•  VCCTEF is equipped as an adaptive wing control technology
19 Flaps (4 Inboard,
10 Flaps, 2 Camber
15 Outboard), 3
Segments per Flap
Camber Segments
per Flap
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