Control of Tailless
Morphing Aircraft
Office of Naval Research - Young Investigator Program Award
June 2018 - May 2022
$510,000
Project Overview
The next generation of fighter aircraft will be tailless. One significant challenge that must be addressed in order to make this a reality is yaw control. The present work considers the use of morphing technology to produce sufficient roll, pitch, and yaw control for tailless aircraft. The overall hypothesis is that the fundamental relationships between aerodynamics and wing morphology can be exploited to produce adequate longitudinal and lateral control for tailless aircraft.
Objectives
Identify relationships between wing morphing and aerodynamics of tailless aircraft
Characterize the morphing input parameters that produce desired control outputs
Assess the accuracy of the predicted relations
Evaluate the control relationships on a full free-body dynamic system
Statistics
11 Students
7 Journal Publications
119 Journal Publication Pages
15 Conference Papers
15 Conference Presentations
3 PhD Dissertations
3 MS Theses
4 Public Software Packages on Github
2 Publicly Available Aircraft Designs
100+ Student/Advisor Meetings
49,000+ Lines of Code
18 Morphing-Wing Concepts
194 Morphing-Wing Prototypes
10,000+ Hours of 3D printing
100+ kg PLA
13 Fully 3D Printed Airframes
8 Take Offs
2 Purposeful Landings
2 Follow On studies
NSF flutter study
BIRE flight test portion
Final Presentation Recordings
1- Introduction
2- Lift Distributions
3- Analytic Roll/Yaw Control
4- Aileron Placement
5- Swept and Crescent Wings
6- Lifting-Line Algorithm for Wings with Sweep
7- MachUp X
8- Morphing Wing Design
9- Manufacturing and Assembly
10- Aircraft Checkout
11- Control Mapping
12- Flight Testing
13 - Recap
Full Presentation Playlist
Publications
Journal Publications
Modern Implementation and Evaluation of Lifting-Line Theory for Complex Geometries
Goates, C., and Hunsaker, D. F., “Modern Implementation and Evaluation of Lifting-Line Theory for Complex Geometries,” Journal of Aircraft, In Review
Accuracy of KĂĽchemann's Prediction for the Locus of Aerodynamic Centers on Swept Wings
Moorthamers, B., and Hunsaker, D. F., “Accuracy of Küchemann's Prediction for the Locus of Aerodynamic Centers on Swept Wings,” The Aeronautical Journal, April 2022, 21 pages, DOI: 10.1017/aer.2022.34.
Minimum-Series Twist Distributions for Yawing-Moment Control During Pure Roll
Hunsaker, D. F., Moorthamers, B., and Joo, J., “Minimum-Series Twist Distributions for Yawing-Moment Control During Pure Roll,” Zeitschrift für Angewandte Mathematik und Mechanik, May 2021, 19 pages, DOI: 10.1002/zamm.201900177
Aileron Size and Location to Minimize Induced Drag During Roll Initiation
Brincklow, J., and Hunsaker, D. F., “Aileron Size and Location to Minimize Induced Drag During Roll Initiation,” The Aeronautical Journal, Vol. 125, No. 1287, 2021, pp. 807–829, DOI: 10.1017/aer.2020.139
General Approach to Lifting-Line Theory, Applied to Wings with Sweep
Reid, J. T., and Hunsaker, D. F., “A General Approach to Lifting-Line Theory, Applied to Wings with Sweep,” Journal of Aircraft, Vol. 58, No. 2, 2021, pp. 334-346 DOI: 10.2514/1.C035994
Adverse-Yaw Control During Roll for a Class of Optimal Lift Distributions
Hunsaker, D. F., Montgomery, Z. S., and Joo, J. J., "Adverse-Yaw Control During Roll for a Class of Optimal Lift Distributions," AIAA Journal, Vol. 58, No. 7, pp. 2909-2920, 2020, DOI: 10.2514/1.J059038
Minimising induced drag with weight distribution, lift distribution, wingspan, and wing-structure weight
Phillips, W. F., Hunsaker, D. F., and Taylor, J. D., "Minimising induced drag with weight distribution, lift distribution, wingspan, and wing-structure weight," The Aeronautical Journal, Vol. 124, No. 1278, pp. 1208-1235, 2020, DOI: 10.1017/aer.2020.24
Designing Wing Twist or Planform Distributions for Specified Lift Distributions
Phillips, W. F. and Hunsaker, D. F., "Designing Wing Twist or Planform Distributions for Specified Lift Distributions," Journal of Aircraft, Vol. 56, No. 2, pp. 847-849, 2019, DOI: 10.2514/1.C035206
Conference Publications
Control Mapping Methodology for Roll, Pitch, and Yaw Control on Morphing-Wing Aircraft
Montgomery, Z., and Hunsaker, D. F., “Control Mapping Methodology for Roll, Pitch, and Yaw Control on Morphing-Wing Aircraft,” AIAA SciTech Forum, January 2022, AIAA-2022-2531, DOI: 10.2514/6.2022-2531
Design and Performance of a 3D-Printed Morphing Aircraft
Snow, S. A., and Hunsaker, D. F., “Design and Performance of a 3D-Printed Morphing Aircraft,” AIAA Scitech Forum Virtual Event, January 2021, AIAA-2021- 1060 DOI: 10.2514/6.2021-1060
3D-Printed Wings with Morphing Trailing-Edge Technology
Moulton, B. C., and Hunsaker, D. F., “3D-Printed Wings with Morphing Trailing-Edge Technology,” AIAA Scitech Forum Virtual Event, January 2021, AIAA-2021-0351 DOI: 10.2514/6.2021-0351
Controlling Roll-Yaw Coupling with Aileron Placement and Wing Twist
Brincklow, J. R., Montgomery, Z. S., and Hunsaker, D. F., "Controlling Roll-Yaw Coupling with Aileron Placement and Wing Twist," AIAA SciTech Forum Virtual Event, January 2021, DOI: https://doi.org/10.2514/6.2021-0327Â
Sensitivity and Estimation of Flying-Wing Aerodynamic, Propulsion, and Inertial Parameters Using Simulation
Thurgood, J. W., and Hunsaker, D. F., "Sensitivity and Estimation of Flying-Wing Aerodynamic, Propulsion, and Inertial Parameters Using Simulation," AIAA SciTech Forum Virtual Event, January 2021, AIAA-2021-1528, DOI: 10.2514/6.2021-1528Â
Estimation of Incompressible Swept-Wing Aerodynamics Using Low-Fidelity Methods
Moorthamers, B., Wiberg, D., and Hunsaker, D. F., "Estimation of Incompressible Swept-Wing Aerodynamics Using Low-Fidelity Methods," AIAA SciTech Forum Virtual Event, January 2021, AIAA-2021-1825, DOI: 10.2514/6.2021-1825
Practical Implementation of a General Numerical Lifting-Line Method
Goates, C., and Hunsaker, D. F., "Practical Implementation of a General Numerical Lifting-Line Method," AIAA SciTech Forum Virtual Event, January 2021, AIAA-2021-0118, DOI: 10.2514/6.2021-0118
Optimization of Ailerons to Minimize Induced Drag in Roll
Brincklow, J. R., and Hunsaker, D. F., “Optimization of Ailerons to Minimize Induced Drag in Roll,” AIAA Scitech Forum, Orlando, Florida, January 2020, AIAA-2020-0279, DOI: 10.2514/6.2020-0279
Accuracy of KĂĽchemann's Prediction for the Locus of Aerodynamic Centers on Swept Wings
Moorthamers, B., and Hunsaker, D. F., “Accuracy of Küchemann's Prediction for the Locus of Aerodynamic Centers on Swept Wings,” AIAA Scitech Forum, Orlando, Florida, January 2020, AIAA-2020-0533 , DOI: 10.2514/6.2020-0533
Ludwig Prandtl’s 1933 Paper Concerning Wings for Minimum Induced Drag, Translation and Commentary
Hunsaker, D. F., and Phillips, W. F., “Ludwig Prandtl’s 1933 Paper Concerning Wings for Minimum Induced Drag, Translation and Commentary,” AIAA Scitech Forum, Orlando, Florida, January 2020, AIAA-2020-0644 , DOI: 10.2514/6.2020-0644
Control of Adverse Yaw During Roll for a Class of Optimal Lift Distributions
Hunsaker, D. F., Montgomery, Z. S., and Joo, J. J., “Control of Adverse Yaw During Roll for a Class of Optimal Lift Distributions,” AIAA Scitech Forum, Orlando, Florida, January 2020, AIAA-2020-1264, DOI: 10.2514/6.2020-1264
A General Approach to Lifting-Line Theory, Applied to Wings with Sweep
Reid, J. T. and Hunsaker, D. F., “A General Approach to Lifting-Line Theory, Applied to Wings with Sweep,” AIAA Scitech Forum, Orlando, Florida, January 2020, AIAA-2020-1287, DOI: 10.2514/6.2020-1287
Minimizing Induced Drag with Weight Distribution, Lift Distribution, Wingspan, and Wing-Structure Weight
Phillips, W. F., Hunsaker, D. F., and Taylor, J., “Minimizing Induced Drag with Weight Distribution, Lift Distribution, Wingspan, and Wing-Structure Weight,” AIAA Aviation Forum, Dallas, Texas, June 2019, AIAA-2019-3349, DOI: 10.2514/6.2019-3349
Effects of Sweep on Airfoil Section Properties
Reid, J. T., and Hunsaker, D. F., “Effects of Sweep on Airfoil Section Properties,” AIAA Aerospace Sciences Meeting, San Diego, California, January 2019, AIAA-2019-2118, DOI: 10.2514/6.2019-2118
Aerodynamic Center at the Root of Swept, Elliptic Wings in Inviscid Flow
Moorthamers, B., and Hunsaker, D. F., “Aerodynamic Center at the Root of Swept, Elliptic Wings in Inviscid Flow,” AIAA Aerospace Sciences Meeting, San Diego, California, January 2019, AIAA-2019-0032, DOI: 10.2514/6.2019-0032
Theses / Dissertations
Zach Montgomery
PhD Dissertation
2022
Bruno Moorthamers
PhD Dissertation
2021
Ben Moulton
MS Thesis
2021
Jackson ReidÂ
PhD Dissertation
2020
Software Packages
Open Aircraft Designs
Aircraft Design, Print, and Assembly
Conformal Flap Design and Prototyping
Many videos available here.
Final Conformal Flap Design
Horizon Airframe 3D Printing Time Lapse
Horizon Airframe Assembly Time Lapse
Glide Test
April 15, 2021
Purpose: To test the following:
static longitudinal and lateral stabilityÂ
CG location
Outcome: Successful glide test. CG location seems to produce adequate static stability.
1st Powered Test
May 3, 2021
Aircraft: V3
Purpose: Test the following:
Structural designÂ
Controllability using Mode 1 (Safety mode with pure elevons)
Adequacy of the ducted fans for propulsion
Outcomes: Aircraft exhibited aeroelastic behavior with repeated instances of intermittent flutter (see t=1.25 min). Test ended with catastrophic flutter event at t=2:10 min. Controllability difficult to discern due to flutter. Ducted fans produced less thrust than expected. Trim required a throttle setting of about 75%.
Flight Time: 00:01:49
2nd Powered Test
June 29, 2021
Aircraft: V4
Purpose: Test the following:
Improved structural design with added carbon-fiber reinforcement in spar caps
Controllability using Mode 1 in the absence of flutter events
Adequacy of the ducted fans for propulsion with new ESC
Outcome: Aircraft sufficiently rigid. No flutter issues. Trim required less throttle (about 66%) most likely due to new ESC. Flight test routine and documentation greatly improved. Dutch roll not as damped as desirable for good handling qualities (see t=4:57 in video). Intermittent loss of signal between receiver and transmitter caused intermittent pitch pulses throughout flight (see t=2:07). Loss of signal eventually lead to catastrophic loss of control (see t=5:16). Loss of signal most likely due to a loose connection on the receiver.
Flight Time: 00:04:18
3rd Powered Test
October 7, 2021
Aircraft: V6 M2
Purpose: Test the following:
Improved design of center-section conformal flap
Data acquisition with Pixhawk 4
Controllability in Mode 2
Determine ranges of CL, pbar, Cm, and Cn commanded by pilot during a nominal flight
(Secondary) Evaluate deflections from video compared to commanded deflections
Outcome: Crash on takeoff. Video and other data used for crash analysis.
Flight Time: 00:00:06
4th Powered Test
November 4, 2021
Aircraft: V7 M2
Purpose: Test the following:
Improved launch methodology
Improved design of center-section conformal flap
Data acquisition with Pixhawk 4
Controllability in Mode 2
Determine ranges of CL, pbar, and Cm commanded by pilot during a nominal flight
(Secondary) Evaluate deflections from video compared to commanded deflections
Outcome: Clean launch. Stable with plenty of power. Center section conformal flap checks out. Sufficient data collected to test ranges of pbar and Cm commanded by pilot. Aircraft felt sluggish in the air. Motors sputtered and servos froze in air repeatedly. Could be due to loss of signal. This behavior caused final crash.
Flight Time: 00:03:00
5th Powered Test
April 27, 2022
Aircraft: V8 M2
Goals:
Clean Launch
Zero drops in communication
Test Mode 2
Purposeful Landing
Outcome: Clean launch. Stable with plenty of power in Mode 1. Zero drops in communication. When switching to Mode 2, the aircraft was trimmed (from Mode 1) with pitch up. The aircraft pitched up as it entered Mode 2 and entered a glide slope that could not be shaken. Hard landing, but with wings level.
Flight Time: 00:01:32
6th Powered Test
May 23, 2022
Aircraft: V9 M2
Goals:
Clean Launch
Zero drops in communication
Test Mode 2
Purposeful Landing
Outcome: Issue during launch. Launch mechanism wrapped around wing. Wing snapped due to possible faulty construction.
Flight Time: 00:00:02
7th Powered Test
June 6, 2022
Aircraft: V10 M2
Goals:
Clean Launch
Zero drops in communication
Test Mode 2
Purposeful Landing
Outcome: Nearly perfect flight. Clean launch. Grazed the ground a little close to the bungee stakes during launch. Solid flight. Spent 2 minutes 12 seconds in Mode 2. Firm touch down broke up the aircraft.
Flight Time: 00:04:36
8th Powered Test
June 9, 2022
Aircraft: V11 M2
Goals:
Clean Launch
Mode 4 Yaw Control
Successful Landing
Outcome: Beautiful launch. Clean transition from Mode 1 to Mode 4. Successful turn in Mode 4. Tested right and left yaw command. Flutter event caused aircraft to break up in the air.
Flight Time: 00:02:29
Annotated Yaw Control and Flutter Event
Control Mapping
Control surface deflections as viewed from the back of the aircraft.
These deflections depend on commands from the pilot as well as the current state of the aircraft.
Mode 1 (Safety)
Control surfaces act in unison as elevons.
Mode 2
Minimum drag with prescribed rolling rate and pitching moment.
Mode 3
Minimum drag and zero yawing moment with prescribed rolling rate and pitching moment.
Mode 4
Minimum drag with prescribed rolling rate, pitching moment, and yawing moment.
Mode Demonstration on the Horizon Aircraft.
Students
PhD
Jackson Reid
Bruno Moorthamers
Zachary Montgomery
Cory Goates
MS
Josh Brincklow
Jaden Thurgood
Sabrina Snow
Ben Moulton
Undergraduate
Dallin Wiberg
Josh Hurwitz
Weston Bowcutt
