Parent Child Unmanned Aerial Vehicles and the Structural Dynamics of an Outboard Horizontal ...

136 Pages·2013·8.41 MB·English

Parent Child Unmanned Aerial Vehicles and the Structural
Dynamics of an Outboard Horizontal Stabilizer Aircraft
by
Jason Kepler
Submitted to the Department of Aeronautics and Astronautics in
partial fulfillment of the requirements for the degree of
Master of Science in Aeronautics and Astronautics
at the
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
June 2002
© Massachusetts Institute of Technology. All Rights Reserved.
Au tho r ........................................F.-.- .-.-.-.-.-.-.-. .-.--..--...
Departni n autics an A ronautics
May 12, 2002
A
Certified by ....................................
f &hn J. Deyst
Professor of Aeronautics and Astronautics
Thesis Supervisor
A ccepted by .............................
Wallace E. Vander Velde
Professor of Aeronautics and Astronautics
Chairman, Committee of Graduate Studies
MASSACHOSETTS WNSTITUTE
OF TECHNOLOGY
AERO AUG 13 2002
LIBRARIES
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Parent Child Unmanned Aerial Vehicles and the
Structural Dynamics of an Outboard Horizontal
Stabilizer Aircraft
by
Jason Kepler
Submitted to the Department of Aeronautics and Astronautics on
May 12, 2002, in partial fulfillment of the requirements for the
degree of Master of Science in Aeronautics and Astronautics
Abstract
In the fall of 1998, MIT and Draper Laboratory formed a partnership program called Par-
ent Child Unmanned Aerial Vehicle (PCUAV) to provide a means of providing upclose
surveillance at a distance. The premise of the project was to create a tiered system of coop-
erative autonomous aircraft. A large Parent aircraft was designed to carry a smaller Mini
aircraft to a target site and release it to descend for upclose surveillance. Meanwhile, the
Parent provides a communications link between the Mini and a ground station at the point
of departure. At the completion of a surveillance mission the Parent retrieves the Mini and
carries it home.
This thesis discusses the system components for the PCUAV project, specifically concen-
trating on the flight vehicles. The design, building, and flight testing phases for each vehi-
cle are detailed. Special attention is given to the Parent vehicle, which utilizes an
Outboard Horizontal Stabilizer (OHS) configuration. The structural dynamics and both
aeroelastic and servo aeroelastic properties of the plane were studied using Aswing and
are reported on here.
Thesis Supervisor: John J. Deyst
Title: Professor of Aeronautics and Astronautics
Thesis Supervisor: Marthinus C. van Schoor
Title: Lecturer, Department of Aeronautics and Astronautics
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Table of Contents
Table of Contents ................................................................................................... 5
List of Figures ....................................................................................................... 7
List of Tables ............................................................................................................ 11
Acknow ledgm ents .................................................................................................. 13
List of Acronym s and Sym bols .............................................................................. 15
1. Introduction ....................................................................................................... 17
1.1 Background and M otivations of PCUAV .............................................. 17
1.2 Background of the Outboard Horizontal Stabilizer Configuration ..... 19
1.3 Thesis Overview ................................................................................... 20
2. PCU AV System ................................................................................................... 21
2.1 Chapter Overview ................................................................................. 21
2.2 The PCUAV System Concepts ................................................................ 21
2.2.1 Typical Flight .............................................................................. 21
2.2.2 Key Enablers .............................................................................. 23
2.2.3 Reintegration .............................................................................. 24
2.3 Com ponents of PCUAV ........................................................................ 27
2.3.1 Parent Vehicle ............................................................................ 28
2.3.2 M ini Vehicle ............................................................................... 29
2.3.3 Avionics Testbed Aircraft ............................................................ 31
2.3.4 Payload Delivery Vehicle ............................................................ 32
2.3.5 Mini-Parent Integration Mechanism (MPIM) ............... 33
2.3.6 M id-Air Recovery System .......................................................... 36
2.3.7 Com mu nications and Surveillance .............................................. 37
2.3.8 Flight Avionics ............................................................................ 38
2.4 Chapter Sum ma ry ................................................................................ 43
3. UAV Building and Testing .................................................................................. 45
3.1 Chapter Overview ................................................................................ 45
3.2 OH S Parent Vehicle .............................................................................. 45
3.2.1 Advantages and Disadvantages of the OHS ................................ 45
3.2.2 OH S Parent Design Process ....................................................... 47
3.2.3 OHS Construction ........................................ 48
3.2.4 OH S Testing and Updating ......................................................... 52
3.3 M ini Vehicle .......................................................................................... 56
3.3.1 M ini Design Process ................................................................... 56
3.3.2 M ini Construction ........................................................................ 57
3.3.3 M ini Testing ................................................................................. 60
3.4 Avionics Testbed Aircraft ...................................................................... 61
3.4.1 Advantages and Disadvantages of the ATA ................................ 61
3.4.2 W ork done on ATAs ................................................................... 62
3.5 ATA Testing ......................................................................................... 63
3.6 Chapter Sum ma ry ................................................................................ 63
4. Structural M odeling of the Parent ..................................................................... 65
4.1 Chapter Overview ................................................................................. 65
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4.2 Structural and Inertial Properties of the Parent ..................................... 65
4.2.1 Area M oments of Inertia ............................................................. 65
4.2.2 W eight and M ass M oment of Inertia ............................................ 70
4.3 Analysis Process .................................................................................. 71
4.4 Natural Frequencies and M ode Shapes of the Parent ........................... 75
4.5 Chapter Overview ................................................................................ 77
5. Aeroelasticity .................................................................................................... 79
5.1 Chapter Overview ................................................................................ 79
5.2 Aeroelasticity of the Parent UAV ......................................................... 79
5.3 Flight Dynamics of Parent ..................................................................... 82
5.4 Servo Aeroelasticity of Parent .............................................................. 84
5.5 Chapter Summary ................................................................................ 88
6. Summary and Conclusions ................................................................................. 89
6.1 Thesis Summary ................................................................................... 89
6.1.1 PCUAV System Summary ............................................................. 89
6.1.2 Suggestions for UAV Improvements ......................................... 90
6.1.3 Flight Tests .................................................................................. 92
6.1.4 Structural Modeling of OHS Aircraft Summary and Conclusions .92
Appendix A Vehicle Drawings ......................................................................... 97
A. 1 Three View Drawings of PCUAV Parent Aircraft ............................... 98
A.2 Three View Drawings of PCUAV NGM I ............................................... 99
A.3 Three View Drawings of PCUAV NGM II ............................................. 100
A.4 Three View Drawings of PCUAV ATA I&II .................... 101
A.5 Building Plans for NGM II ...................................................................... 102
A.6 W ing M oment of Inertia Spreadsheet ...................................................... 104
Appendix B Aswing and Related Code for the Parent .......................................... 105
B.1 Description of Aswing ............................................................................. 105
B.2 Aswing Code for the Parent ..................................................................... 107
Appendix C Aswing Results ................................................................................. 113
C.1 M ode Shapes ............................................................................................ 114
C.2 Bode Plots ................................................................................................ 125
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List of Figures
Figure 1.1 Multi-Tiered System Concept ......................................................... 18
Figure 1.2 Outboard Horizontal Stabilizer Parent Vehicle ................................ 19
Figure 2.1 Communications Hierarchy for PCUAV .......................................... 23
Figure 2.2 Phase One of Reintegration .............................................................. 25
Figure 2.3 Phase Two Detection and Navigation System ................................. 26
Figure 2.4 Parent Aircraft Inside a Dodge Caravan .......................................... 29
Figure 2.5 (Left) NGMI, (Right) NGMII .......................................................... 30
Figure 2.6 The First Avionics Testbed Aircraft ................................................. 32
Figure 2.7 Payload Delivery Vehicle ................................................................. 33
Figure 2.8 Original M PIM Design ........................................................................ 34
Figure 2.9 Parent Aircraft with MPIM Attached .................................................. 34
Figure 2.10 D etail of M PIM ................................................................................ 35
Figure 2.11 MARS Directional Finder ................................................................ 37
Figure 2.12 Rover with Surveillance Equipment on Top .................................... 38
Figure 2.13 NGMII Flight Control Avionics ....................................................... 39
Figure 2.14 Parent's Avionics Structure .............................................................. 43
Figure 3.1 Vortex Induced Angle of Attack at Tail Position ............................ 46
Figure 3.2 Parent's Spar D etail .......................................................................... 49
Figure 3.3 Parent Wing Composite Layup ....................................................... 50
Figure 3.4 (Left) Author with Parent's Tail, (Right) Parent's Fuselage Frame .... 51
Figure 3.5 Bending Moment in Parent's Wing ................................................ 53
Figure 3.6 Second Landing of OHS Parent ....................................................... 54
Figure 3.7 Avionics Inside NGMII Fuselage ..................................................... 58
Figure 3.8 Cross Section of NGMII Wing ....................................................... 59
Figure 4.1 Cross Section of the Parent's Tail Booms ....................................... 66
Figure 4.2 Cross Section of the Parent's Wing ................................................. 68
Figure 4.3 Aswing Geometry for Parent ............................................................ 72
Figure 4.4 Velocity Sweep of Parent ................................................................ 74
Figure 4.5 Root Locus Plot for Parent .............................................................. 75
Figure 5.1 First flutter mode of OHS Parent ..................................................... 80
Figure 5.2 Root Locus Plot of OHS Parent with Three Pound Weights
on Each Tail and Counterweight Attached to Fuselage ................... 81
Figure 5.3 Root Locus Plot of OHS Parent with Three Pound Weights
on Each Tail and Counterweight Attached to Wingtips' Leading Edges 82
Figure 5.4 Blow Up of Root Locus Near Origin .............................................. 83
Figure 5.5 Bode Plots of Parent Roll Rate Response to Unit Aileron Input,
A irspeed = 70 ft/sec., @ S.L. .............................................................. 85
Figure 5.6 Bode Plots of Parent Pitch Rate Response to Unit Elevator Input,
A irspeed = 70 ft/sec., @ S.L. .............................................................. 86
Figure 5.7 Bode Plots of Parent Yaw Rate Response to Unit Rudder Input,
A irspeed = 70 ft/sec., @ S.L. .............................................................. 87
Figure A. 1 Orthogonal Views of OHS Parent ................................................... 98
Figure A.2 Orthogonal Views of New Generation Mini .................................... 99
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Figure A.3 Orthogonal Views of Second New Generation Mini .......................... 100
Figure A.4 Orthogonal Views of Two Avionics Testbed Aircraft ........................ 101
Figure A.5 Building Plans for NGM II Fuselage .............................................. 102
Figure A.6 Building Plans for NGM II W ing and Tail .......................................... 103
Figure C.1 First Mode Shape of OHS Parent, Asymmetric Vertical
Tail Boom Bending, Airspeed = 70 ft/sec, @ Sea Level .................... 114
Figure C.2 Second Mode Shape of OHS Parent, Asymmetric Horizontal
Tail Boom Bending, Airspeed = 70 ft/sec, @ Sea Level .................... 115
Figure C.3 Third Mode Shape of OHS Parent, Symmetric Wing Bending,
Airspeed = 70 ft/sec, @ Sea Level ...................................................... 116
Figure C.4 Fourth Mode Shape of OHS Parent, Asymmetric Wing Twist,
Airspeed = 70 ft/sec, @ Sea Level ...................................................... 117
Figure C.5 Fifth Mode Shape of OHS Parent, Symmetric Wing Twist,
Airspeed = 70 ft/sec, @ Sea Level ...................................................... 118
Figure C.6 Sixth Mode Shape of OHS Parent, Asymmetric Horizontal
Stabilizer Bending, Airspeed = 70 ft/sec, @ Sea Level ...................... 119
Figure C.7 Seventh Mode Shape of OHS Parent, Symmetric Horizontal
Stabilizer Bending, Airspeed = 70 ft/sec, @ Sea Level ...................... 120
Figure C.8 Eighth Mode Shape of OHS Parent, Second Wing Bending,
Airspeed = 70 ft/sec, @ Sea Level ...................................................... 121
Figure C.9 Ninth Mode Shape of OHS Parent, Fore-Aft Wing Bending,
Airspeed = 70 ft/sec, @ Sea Level ...................................................... 122
Figure C.10 Tenth Mode Shape of OHS Parent, Asymmetric Vertical
Tail Bending, Airspeed = 70 ft/sec, @ Sea Level ............................... 123
Figure C.11 Eleventh Mode Shape of OHS Parent, Symmetric Vertical
Tail Bending, Airspeed = 70 ft/sec, @ Sea Level ............................... 124
Figure C.12 Gain Plot of Roll Rate vs. Aileron Input Frequency for
Flexible OHS Parent, Airspeed = 70 ft/sec, @ Sea Level 125
Figure C.13 Phase Plot of Roll Rate vs. Aileron Input Frequency For
Flexible OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ................... 126
Figure C.14 Gain Plot of Pitch Rate vs. Elevator Input Frequency,
Flexible OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ................... 127
Figure C.15 Phase Plot of Pitch Rate vs. Elevator Input Frequency,
Flexible OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ................... 128
Figure C.16 Gain Plot of Yaw rate vs Rudder Input Frequency For
Flexible OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ................... 129
Figure C.17 Phase Plot of Yaw Rate vs. Rudder Input Frequency For
Flexible OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ................... 130
Figure C.18 Gain Plot of Roll Rate vs. Aileron Input Frequency for
Rigid OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ....................... 131
Figure C.19 Phase Plot of Roll Rate vs. Aileron Input Frequency For
Rigid OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ....................... 132
Figure C.20 Gain Plot of Pitch Rate vs. Elevator Input Frequency,
Rigid OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ....................... 133
Figure C.21 Phase Plot of Pitch Rate vs. Elevator Input Frequency,
Rigid OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ....................... 134
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Figure C.22 Gain Plot of Yaw rate vs. Rudder Input Frequency For
Rigid OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ....................... 135
Figure C.23 Phase Plot of Yaw Rate vs. Rudder Input Frequency For
Rigid OHS Parent, Airspeed = 70 ft/sec, @ Sea Level ....................... 136
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