Investigating Segmented TrailingEdge Surfaces for Full Authority Control of a UAV

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Investigating Segmented Trailing-Edge Surfaces
for Full Authority Control of a UAV

• Mujahid Abdulrahim
• Rick Lind

Senior UndergraduateUniversity of FloridaDept.
of Mechanical Aerospace Engineering
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Outline

• Introduction to Morphing
• Aircraft Systems
• Flight Testing
• Data Analysis Modeling
• Closing Remarks

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The Future of Aircraft Control
Control Degrees of Freedom
http//www.larc.nasa.gov
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Morphing

• Improved maneuverability
• Reduced weight
• Decoupled control
• Reconfigurable control
• Redundancy/survivability
• Multi-role aircraft

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Project Objective

• Study the effect of multiple control degrees of
  freedom on the controllability of an airplane
• Low-cost flight testbed
• Single-point actuation
• Distributed actuation
• Optimized Control
• Failure Detection/Compensation

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Aircraft SystemsAirframe

• Parameter - Value
• Wingspan 65 inWeight 8
  lbsPayload 5 lbsCruise speed 45 mph

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Aircraft SystemsSegmented Control Surfaces

• Servo-actuator imbedded in wing
• Indexed from 0 (left tip) to 15 (right tip)
• Surface deflection -45º to 45º
• Angular resolution 0.35 º
• Deflection speed 0.08s to 45º

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Aircraft SystemsControl Hardware
Pilot command
Microcontroller
Control surfaces
Neutral
Differential
Collective
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Aircraft SystemsInstruments and Sensors
Aircraft State Symbol Measured Range roll, pitch,
yaw rate p, q, r 300º/s x, y, z
acceleration ax, ay, az 50 G aileron
position da 45º elevator
position de 30º rudder
position dr 45º
micro data acquisition system
sensor board
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Flight TestingManeuvers

• Procedures developed by NASADryden Flight
  Research Center
• Control surface pulse
• Perturbations about trim condition
• Small maneuvers, within linear range
• Pulsed surfaces
• Aileron (using 16 surfaces)
• Rudder
• Elevator
• Differential wing segment
• Collective wing segment

http//www.dfrc.nasa.gov
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Flight TestingProcedures Objectives

• Aircraft and instruments initialized
• Rolling take-off
• Climb to altitude
• Flightcard
• Trim for level flight
• Small maneuver,return to trim
• 180º turn
• Landing
• Data recovery

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Flight TestingAileron Control Pulse
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Flight TestingRudder Control Pulse
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Flight TestingDifferential Segment Control Pulse
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Flight TestingElevator Control Pulse
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Flight TestingCollective Segment Control Pulse
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Data Analysis ModelingSystem Identification

• Black Box approach
• Flight data represented as ARX model with
  optimized coefficients
• Linear models of airplane dynamics
• Considers lateral and longitudinal dynamics as
  decoupled

pmeasured
daileron
psimulated
MODEL
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Data Analysis ModelingLateral Dynamics
Aileron
Rudder
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Data Analysis ModelingLateral Dynamics
Differential segment pairs
Segment pair0 15
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Data Analysis ModelingLateral Dynamics
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Data Analysis ModelingLongitudinal Dynamics
Elevator
Collective uniform deflection
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Data Analysis ModelingLongitudinal Dynamics
Collective segment pairs
Segment pairs1-14 2-13
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Data Analysis ModelingRoll Frequency Response
Aileron
Wing segments
Superpositionedtotal of segments

• Single surface sum of many surfaces
• Simplifies control design

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Data Analysis ModelingDutch Roll Frequency

• Dutch roll frequency dependent on wingspan
• MiG model is in-line with other aircraft

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Conclusions

• Project objectives met
• Flight tested over 6 months
• Used as lateral and longitudinal control
  effectors
• Linear models closely matched flight data
• Segment control authority can be treated
  individually or in groups

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Acknowledgments

• Martin Waszak
• Dr. Mark Motter
• Mike French
• Jason Grzwyna
• Joe Pippin
• Dr. Peter Ifju