critical design review david akerman, jen getz, greg goldberg, zach hazen, jason patterson, benjamin...

Critical Design ReviewDavid Akerman, Jen Getz, Greg Goldberg, Zach Hazen,

Jason Patterson, Benjamin ReeseDecember 4, 2006

PRV(Peregrine Return Vehicle)

2

Presentation Outline

• Project Objectives and Overview• System Architecture• Design Elements

– Mechanical Design Elements– Electrical Design Elements– Software Design Elements

• Integration Plan• Verification and Test Plan• Project Management Plan• Questions

3

Requests for Action

• Flutter Analysis / Control Gains– Open (as of 12/4/06)

• Manufacturing difficulties– Closed

• Federal Aviation Administration Requirements– Closed

4

SYSTEM ARCHITECTURE

5

Objective OverviewObjective:

To provide the Colorado Space Grant Consortium with a

reusable vehicle that can return student built science

payloads to a selected target.

6

Requirements Overview

• Combined weight of Vehicle, EOSS telemetry beacon, and payload must not exceed 26 lb– Payload weight 8.3 lb.– EOSS telemetry beacon weight 2.7 lbs– Vehicle structure and subsystems must weight < 15 lbs

• Vehicle must carry five, 4.7-inch cubical student-built science payloads, weighing 1.65 lb each.– Vehicle must have the necessary volume to accommodate payloads,

subsystems, and internal structure.

• Ground Impact velocity must not exceed 15 ft/sec – Vehicle structure must be durable and resilient to withstand heavy shock

loads– Parachute touchdown required (no runway available)

• Vehicle must be able to land within ¼ mile of an intended target chosen prior to launch.

7

System Design

8

• Subsystems– Avionics– Payload Structure– Airframe– Parachute Deployment

System– Thermal Control

System

System Design

9

System Design: Avionics Rack

• Houses– Auto-Pilot

MP2028g– Power regulation

board– Thermal control

board– Video Overlay

Board• Provides structural

support• Easy access for

removal

10

System Design: Payload Structure

• Payload Structure– Secure payloads

during flight– Supply support for

payload weight of 8.2 lbs.

– Provides mounting for avionics rack

– Supports front spar

11

System Design: Airframe

•Provides stiffness

•Supports and protects payload

•Provides mounting points for control surfaces

12

System Design: Parachute Deployment System

• Parachute Deployment System

– Deploys parachute using pyrotechnic charge

– Triggered by auto-pilot or pressure sensors

– Touchdown velocity of 15 ft/s

13

Proto-Peregrine Results

• Flight Behavior of Flying Wing

• Stable Configuration• Adequate Control

Response (Low Altitude)

• Manufacturing Experience

• Material Selection

14

MECHANICAL DESIGN ELEMENTS

15

Design to Specification

• Fuselage– Designed to withstand up to

10 g loads in dive pullout manuver.

– Designed to withstand parachute deployment.

– Designed to survive an impact of 15 ft/s and be re-usable.

• Wings– Must withstand 10 g-loads

(260 lbf) in pullout manuver.

• Payload Bay – Designed to acomodate five,

105.4 in3 cubes (4.73” on all sides).

– Support a combined payload mass of 10 lb.

– Field of view through the fuselage for each box.

– Nadir-pointing in ascension phase

• Parachute Deployment System– Descent rate of 15 ft/s– Pyrotechnic Parachute

Deployment

Note: The payload will be contained within the fuselage

16

Drawing TreePart Number Description Revision Connects With Drawn By Complete Yes/No Fabricated/Purchased

10-001 Right Wing Assembly A 10-003

13-001 Right Wing Section 2 A 10-001 ZH No Fabricated13-025 Right Wing Section 3 10-001 ZH No Fabricated13-002 Right Winglet Rib A 10-001 ZH No Fabricated13-003 Right Winglet A 10-001 ZH No Fabricated13-019 Right Elevon A 10-001 ZH No Fabricated10-002 Left Wing Assembly A 10-003

13-004 Left Wing Section 2 A 10-002 ZH No Fabricated13-024 Left Wing Section 3 A 10-002 ZH No Fabricated13-005 Left Winglet Rib A 10-002 ZH No Fabricated13-006 Left Winglet A 10-002 ZH No Fabricated13-020 Left Elevon A 10-002 ZH No Fabricated10-003 Center Fuselage Assembly A 10-001, 10-002, 10-004, 10-005

13-007 Center Fuselage Assembly A 10-003 ZH No Fabricated13-022 Right Transition A 10-003 ZH No Fabricated13-023 Left Transistion A 10-003 ZH No Fabricated13-008 Forward Spar A 10-003 ZH No Purchased13-009 Rear Spar A 10-003 ZH No Purchased10-004 Payload Bay Assembly A 10-003

13-010 Right A 10-004 GG Yes Fabricated13-011 Left A 10-004 GG Yes Fabricated13-012 Front A 10-004 GG Yes Fabricated13-013 Rear A 10-004 GG Yes Fabricated13-014 Bottom A 10-004 GG Yes Fabricated13-026 Cover A 10-004 GG Yes Fabricated10-005 Parachute Deployment System A 10-003

13-015 Launch Tube A 10-005 JP Yes Fabricated13-016 Nose Cone A 10-005 JP Yes Fabricated13-017 Blast Plate A 10-005 JP Yes Fabricated13-018 Sabot A 10-005 JP Yes Fabricated10-006 Avionics Rack A 10-004

13-021 Avionics Mounting Rack A 10-006 JP Yes Fabricated

PRV DRAWING TREE

17

Weight BudgetObject Budgeted Weight (lbs) Current Weight (lbs)

Carbon Fiber Spars and Ribs 1.5 1.3

EPP Foam 3.5 3.5

Payload 8.3 8.3

EOSS Package 2.7 2.7

Payload structure 1.75 1.73

Avionics 1.5 1.5

Skin (Thin Plastic / C.F.) ? ?

Parachute 1.75 1.5

Parachute Mechanism 1 1

Misc (Glue, Tape, etc) ? ?

Total Weight 22.00 21.53

Remaining Weight 4.00 4.47

18

Overall System and Subsystems

19

EOSS Payload• Tracking beacon and flight data

collector• Required for launch by FAA• Provided by EOSS• Contains:

– Alinco DJ-C5 dual band credit card radio (144 – 148MHz)

– GPS Receiver – Basic Stamp Processor – TinyTrak 3.0 APRS encoder – Balloon cutaway device

• Weight: 2.7 lbs• Dimensions: 10''L x 5.6"W x 2.5"H• Cannot be taken apart

20

sec15

5.1

00192695.0

26

37000

ftv

C

ft

slug

lbW

DiameterD

e

D

T

o

*Formula from Knacke, T.W. Parachute Recovery Systems Design Manual, 1992.

inftD

vC

WD

o

eD

To

08.12109.10

82

Parachute Deployment System Sizing

21

Parachute Deployment System

22

Airframe Design

Airframe

Stuctures

Recovery System

Payload Science

EOSSRecovery System

Payload Bay

EOSSAvionics

Rack

Bending Flutter Impact

Strength Stiffness Elasticity

Stability L/D

Aerodynamics

Payload Volume Accessibility

23

Payload Structure

• Purpose– Structure to hold payloads– Distribute bending load from the spar– Structure coupled with front spar to

mitigate the force exhibited in pullout maneuver

– Give the ability for the autopilot and avionics bay to be situated over the glider C.G.

• Material– Top of Structure made of rigid PVC– All other surfaces and components

made of Aluminum 6061• Dimensions

– 16.06”L x 9.76”W x 5”H• Projected weight

– 1.75 (lbs)• Faces attached using #2-56 screws• Structure bonded to the inside of the

center section

24

Glider Structure

*Note: Dimensions in inches

25

Glider Center Section

26

Wings

27

ELECTRICAL DESIGN ELEMENTS

28

Design to Specification

• Avionics– Autopilot

• Must control a 20-lb UAV• Must withstand high G-loads

(parachute deployment, high-G turns/pull-outs)

– Controls/Servos• Must provide the torque

necessary to apply aerodynamic forces at high airspeed (Mach 0.4)

– Recovery System • Must slow vehicle to safe

touchdown speed 15 ft/s or 10.23 mph

• Must be reusable• > 90% proven reliability• Must operate independently

– Power Supply• Must be able to provide

reliable voltage and current to Power Distribution Board

• Must be able to provide 3 A-hrs at 8-14 VDC for avionics excluding servos

• Servo battery must be able to provide 3.3 A-hrs at 4.8 VDC

– Power Distribution Board• Needs to provide appropriate

voltage and current to different components

29

Overall Electrical System

GPS Signal

GPS Antenna

MicroPilotMP2028g

Elevon ServosFUTM0035

EOSS GPS Receiver(External to project, will be treated as a packaged payload.)

11.1 VDC Battery(Autopilot/GPS Overlay Boad)

4.8 VDC Battery(Elevon Servos)

GPS Overlay Board

(From Micropilot)

Video CameraCMOS PC131WR

MDVR-11(has internal rechargeable power source)

2 GB Smart Digital Card

Pressure Sensor 1All Sensors

15 PSI-A-4V-MIL


15 PSI-A-4V-MIL

True if = 1000 ft AGL (into pin RA0)

DC RelayOmron Electronics

G6BK-1114P-US-DC5

Servo controlling recovery

parachute releaseFUTM0035

10 VDC Battery(Recovery System)

GPS altitude = 1000 ft AGL (into pin RA2)


Voltage Regulator

LM317

Voltage Regulator

LM317

PIC

18F

452

Voltage Regulator

LM317

(pin out RB0)

30

Electrical Subsystems

• Auto-Pilot System

• Balloon Release System

• Parachute Deployment System

• Servo Controls

• Thermal Control System

• Auto-Pilot System

31

Auto-Pilot

• Provides control for servos

• Triggers parachute deployment

• Power: 11.1 VDC 3300 mAh Li-Po Battery

MicroPilot On Board Components:

•Trimble Lassen SQ GPS Receiver

•3-axis Accelerometer

•Barometric Pressure

•Barometric Airspeed

32

Balloon Release System

• Current EOSS System– NiChrome wire cut

away device• Relay connected to

standard EOSS package

• Signal sent by EOSS closes a relay causing the NiChrome wire to burn through the nylon Parachute Cord

33


• PIC16F84 allows for user to program deployment altitude. Also performs all logic functions

• Accepts trigger from either pressure sensors or auto-pilot• Trigger causes detonation of pyrotechnic charge• Power: 10 VDC Independent battery


15 PSI-A-4V-MIL


15 PSI-A-4V-MIL


DC RelayOmron Electronics

G6BK-1114P-US-DC5

Servo controlling recovery

parachute releaseFUTM0035

10 VDC Battery(Recovery System)

GPS altitude = 1000 ft AGL (into pin RA2)


Voltage Regulator

LM317

Voltage Regulator

LM317

PIC

18F

452

Voltage Regulator

LM317

(Out of pin RB0)

34

Servo Controls

• Futaba FTM0035– 2x Servos Control

Elevons– Input from Auto-Pilot– Power: 4.8 VDC

supplied from separate servo battery

– Torque 89 oz-in– Speed 0.24 sec/60º

35

Thermal System

• Provides thermal control for all electronics

• Temperature of avionics must be maintained above 0ºF

• Ambient temperature at 92,000 ft is -70ºF

• Must keep above 0ºF • Controlled to +/- 2ºF• Power: 5.8 VDC• 8 Watts

36

SOFTWARE DESIGN ELEMENTS

37

Software Break Down

• Flight simulation

• Aerodynamic design

• Autopilot setup

• Autopilot simulation

• Autopilot conditions feed test

38

Flight Simulation

U of WyomingWind Data

Range 40 miAltitude 90,000 ft

Vehicle L/D range

Simulation

Range covered

L/D required to cover range given

Time to target

Dive trough Jetstream from 45,000 ft to 16,000 ft

Heading set towards target

Loops dive angle to optimize range

WeightAreaCd

Inputs Outputs

39

Design Analysis

Range Requirement:40 miles w/winds

Vehicle L/D:5-7 necessary predicted at PDR

Aspect Ratio Oswald’s Efficiency Factor Zero Lift Drag (parasite)

40

Design Analysis

DiD

L

CC

CDL

0

/ARe

CC LDi **

2

ARPeregrine CLcruise CD0 L/Drequired

4 0.5 ~0.02 7

•Assuming the above Values, an efficiency of e > 0.4 should provide necessary L/D

•“Real” Sailplane: e ~ 0.95, typical: e ~0.8

41

Performance Predictions

• CD0 ~ 0.2-0.3– Trade Study,

Estimations

• CL cruise = 0.48– Mission Simulation

• AR = 4.51– Aircraft Geometry

• e = 0.84– Vortex-Lattice, Trade

Studies

• L/D ~ 9.8 - 12.2

42

Design Analysis

Vehicle Must Survive all Flight Regimes

and Be ControllableDerived from PDR Requirements

Flutter Safety Bending Strength Control Gains

43

Analysis Limitations

• Theoretical Flutter Analysis– CFD Model– Representative Wind-

Tunnel Model– Flutter Comparison

• Practical Flutter Prevention– Flight Testing– Autopilot Protection

V

cm

bc

*

** 2

44

Design Analysis

• Flutter and Control Response are both dependent on Dynamic Pressure– Dynamic Pressure for a given glider shape in a

steady glide depends only on the glide angle.• Terminal dive testing will reveal if flutter will

occur at any altitude

SC

angleglideWQ

D

)_sin(*

45

Design Analysis

0 50 100 150 200 250 3000

10

20

30

40

50

60

70

80

90

Airspeed [mph]

Alti

tude

[10

3 ft.

]

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.40

10

20

30

40

50

60

70

80

90

Mach Number

Alti

tude

[10

3 ft.

]

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2

x 106

0

10

20

30

40

50

60

70

80

90

Reynolds Number

Alti

tude

[10

3 ft.

]

0 200 400 600 800 1000 1200 1400 1600 18000

10

20

30

40

50

60

70

80

90

Dynamic Pressure [Pa]

Alti

tude

[10

3 ft.

]

46

Vehicle Stability

• Static Margin = 10%– Chosen from experience, trade

studies– Set with wing placement

• Measure of Directional Stability = 5%– Chosen from experience, trade

studies– Set with winglet sizing

10.0

05.02/*

*

c

xxSM

bS

lS

cgac

wing

ACwingletsF

47

Auto-pilot Setup

PC interface

Control gains are found

Moments of inertia identification routine

Define pitch, yaw, descent rates, etc…

Autopilot Setup

Autopilot is mounted

Control gain schedule

Wait to climb

GPS Navigation

Fly to

Approach

Deploy parachute

Flight path programming

Launch site

GPS lock

Initialize

Auto-pilot integration software

•Servo Configuration

•Elevon controls

•Defines flying wing

•Elevon mixing

•Moments of inertia routine

•Vehicle tilted in specific angles and let to settle

•Rates definition

•Max and min rates desired

•Pitch, yaw, roll, descent

•Angle definition

•Pitch, yaw, roll

48

Autopilot Testing Simulation• Mission Simulation Software Included with

MP2028– Horizonmp

• Provided by Micropilot• Specifically designed for Micropilot MP2028 flight

simulations• Allows Atmospheric and wind data as a simulation

input

49

Recovery System Software

Input

Process

Output

Analog Input from:Pressure Sensor 1

15 PSI-A-4V-MIL

Analog Input from:Pressure Sensor 2

15 PSI-A-4V-MIL

Analog input from:Autopilot GPSMicropilot MP 2028g

Compares current pressure reading to previous reading to determine direction of travel

Compares current pressure reading/GPS reading to a predetermined fixed value

(=1000 feet AGL)

If traveling up..

Deploy Parachute

OR Gate (in code)

If value matches fixed..

Logical 1 from OR Gate

50

INTEGRATION PLAN

51

Assembly Flow Diagram

Complete Aircraft

Avionics Airframe EOSS BeaconParachute

Deployment System

Payload Structure

52

Assembly Diagram: Avionics

Avionics System

Power Distribution

Thermal Control

Flight Control and Navigation

Flight Data Recording

PIC Controller

Ceramic Heaters

Autopilot

RC Receiver

Servos

GPS Overlay Board

Micro DVR

CCD Bullet Cam

Batteries

Power Distribution

Board

To ALL

53

Assembly Diagram: AirframeAirframe

Center Section

Payload Structure

Left Wing Right Wing

Left Transition Right Transition

Left Inner Wing

Spars

Left Outer Wing

Left Wing Tip Rib

Left Elevon

Left Root Rib

Left Mid Wing Rib

Left Winglet

Right Inner Wing

Right Outer Wing

Right Wing Tip Rib

Right Elevon

Right Root Rib

Right Mid Wing Rib

Right Winglet

Retro Incabulator

54

Payload Structure Assembly

Payload Structure

Left Side Face

Top Face

L Brackets(4)

Front Face Rear Face Right Side Face

Bottom Face

55

Assembly Diagram:Parachute Deployment System

56

Functional Test Plan

• Master Plan– Avionics

• Flight Data Recording• Flight Control/Navigation System (FCS)• Power Distribution• Thermal Control

– Airframe• Payload Bay• Complete, “empty” aircraft

– (nothing installed except payload bay)

– EOSS Beacon– Parachute Deployment System

57

Avionics Testing: Flight Data Recording

• Video Recording System:– Test DVR capture/playback.– Verify interfaces between Camera, Autopilot Overlay

board, and DVR. – Test data overlay and storage.

• Data Acquisition/Analysis– Recover data from onboard data logger via RS-232

serial port.– Comparison between acquired data and model.

58

• Auto-pilot:– Simulate flight situation to verify proper function– Integration test

• Power Distribution Board:– Connect board to all components, verify proper function of each

component• Batteries:

– Test full discharge time of cold batteries ~ -40F– Test the thermal output of batteries

• Thermal Control System– Cold-test Avionics Compartment at a temp of ~ -40F in flight

condition– Determine time and temperature at equilibrium

• Ensure equilibrium T is within limits for all components

Avionics Testing

59

Mechanism testing

• EOSS Telemetry Beacon– Physical compatibility test with other systems

in the area (PDM, PLB, airframe)– Radio Frequency interference (RFI) test

• Parachute Deployment System– Canopy test– Pyrodex (Ejection Charge) test– Aircraft Integration Test

60

VERIFICATION AND TEST PLAN

61

Verification and Test Plan

• Total Vehicle Weight < 26 lb– 48 hours prior to launch:

• Weigh all student payloads, determine ideal (balanced) placement in payload bay

• Weigh EOSS beacon package• Weigh vehicle both empty and loaded (Ready-to-

fly configuration)

62

• Touchdown Velocity < 15 ft/sec– 3 months prior to launch:

• Parachute will be tested on a dummy 26-lb load (water jugs, etc) to verify that touchdown velocity is actually < 15 ft/sec

– Extra time allows for rearrangement of deployment system if necessary

– If testing budget allows, we will deploy the parachute via manual RC control at ~1000’ AGL on the full-scale (Flight) model, WITHOUT the autopilot installed.

– If no chute deployment, can intervene via RC.


63

• Landing Accuracy – Vehicle is NOT required to return to launch site– Landing sites will be in rural Eastern Colorado

and will be selected in terms of accessibility.– Landing accuracy will be tested on ½ and full-

scale craft operating under autopilot control• Program landing site, then drop/fly from highest

possible altitude under autopilot control with RC pilot standing by in case of emergency

• Bungee launch, air drop (helicopter, skydive aircraft)


64

• Parachute test– Car test

• Force at the velocity• Cd at the velocity• Tension on string

• Parachute Deployment Test– Test ignition system under different temperatures and ambient

conditions– Launch parachute while on a flat spin– With autopilot failure

• Structural Test– Static loading – Dynamic loading

• Balloon Release System Test– Temperature testing


MANAGEMENT PLAN

66

Organization Chart

Systems EngineerJason Patterson

Project ManagerBenjamin Reese

Fabrication EngineersGreg Goldberg

Zach Hazen

CFO / Webmaster

Jen Getz

Safety Engineer /Asst. Project Manager

David Akerman

AerodynamicsAircraft Simulation

Aircraft Configuration

StructuresMaterials SelectionStructural Design

Design Verification

AvionicsAuto-Pilot

Electronics Design

Testing / Systems Integration

System TestingElectronics Integration

Structural Testing

LeadZach Hazen

David Akerman

Greg Goldberg

LeadDavid Akerman

Benjamin Reese

Greg Goldberg

LeadJen Getz

Jason Patterson

Benjamin Reese

LeadJason Patterson

Zach Hazen

Jen Getz

67

Work Breakdown1.0

PRV Glider

1.2Systems

Engineering

1.3Aerodynamics

1.4Structures

1.5Avionics

1.6Testing &

Verification

1.1Project

Management

1.1.1Project Organization

1.1.2Scheduling

1.1.3Task Management

1.1.4Group Dynamic

1.1.5Communications

1.2.1Systems

Organization

1.2.2Systems Integration

1.3.1Airframe Fabrication

1.3.2Auto-Pilot

Configuration

1.4.1Payload Bay Machining

1.4.2Parachute Structure

Fabrication

1.4.3Payload Bay

Assembly

1.4.4Parachute Structure

Assembly

1.5.2Circuit Board Construction

1.5.4Auto-Pilot

Configuration

1.5.5Avionics Integration

1.6.1Airframe Testing

1.6.2Payload Bay Testing

1.6.3Avionics Testing

1.6.4Assembled Structure

Testing

1.3.3Airframe Assembly

1.4.5EOSS Package

Integration

1.5.1Circuit Board

Layouts

1.5.3Avionics Mounting

1.6.5Assembled Avionics

Testing

1.3.4Glider System

Integration

1.4.6Glider System

Integration

1.6.6Glider System

Integration

68

Project Risk

1. Power System Failure2. Parachute Failure3. Difficulties in Auto-pilot

Programming4. Unrecoverable

Flight Situation Including Flutter

5. Auto-Pilot Failure6. Loss of GPS Signal7. Electronics Malfunction

69

Manufacturing Schedule

70

Test Schedule

71

Monetary Budget

72

Special Needs and Facilities

• Balloon Launch Site – Provided by EOSS and Colorado Space Grant

Consortium

• FAA Approval– Given as long as flight includes EOSS

package• Provides Real Time Telemetry to the FAA

73

QUESTIONS

APPENDIX I: SYSTEM ARCHITECTURE

APPENDIX II: MECHANICAL DESIGN ELEMENTS

76

Avionics Rack

77


78


79

Payload Structure

80

Drawings

81

Drawings

82

Drawings

83

Drawings

84

Drawings

85

Drawings

86

Drawings

87

Drawings

88

Drawings

89

Drawings

90

Drawings

APPENDIX III: ELECTRONIC DESIGN ELEMENTS

92

Recovery System

93

Thermal Control System

94

Auto-Pilot System

APPENDIX IV: SOFTWARE DESIGN ELEMENTS

96

• PID Loops

Autopilot Navigation

APPENDIX V: INTEGRATION PLAN

98

• Payload Capacity: 5 x 4.7-in cubical payloads, 1.65 lb each– 1 week prior to launch:

• Student payloads will be individually fit-checked in a mockup of an individual “payload slot”

• All payloads will be fit-checked together in the vehicle payload bay to check for interference

• Must be able to close and seal the payload bay with all five payloads installed in ready-to-fly configuration (switches, hatches, buttons, etc)


APPENDIX VI: VERIFICATION AND TEST PLAN

100

• Aircraft Integration Test– Determine best mounting arrangement of

loaded launch tube with complete airframe– Ensure that riser lines are securely mounted to

as many spars as possible, and have a free path of travel during chute ejection and inflation


101


• Canopy Test– Drop-check with 26-lb ballast and ~15-ft riser lines,

estimate time and vertical drop distance to canopy inflation, check oscillation characteristics

– Compare actual (measured) vs. predicted (15 ft/sec) touchdown velocity under canopy

• Pyrodex (Ejection Charge) test– Verify that a 1-gram charge can pop the chute (tie-

stowed to keep folding intact for testing) at least 3 feet out of the launch tube (to avoid line tangling)

• Increase charge size as required, if necessary– Check for damage to the tube, investigate properties of

ABS, PVC, and rocket-tube cardboard (Aluminum?)

102

• Complete Aircraft (Mock payloads, no avionics)– Static (+ and -) G-load testing on the wings

• Sandbags loaded slowly, tip deflection measured• Testing to 10 G (Static load of 260 lb, test will be aborted if

signs of trouble are noted, and will not AT ALL proceed beyond 260 lb)

– Shock load testing• “Belly-flop” drop test from 6 feet (arm’s length) and 10 feet

(ladder) onto simulated expected landing terrain (grass, hard dirt)

– Inspect for damage• Parachute “yank” test on main spar area

– Drop test with parachute riser lines connected to a fixed beam– Will simulate g-loads encountered during parachute deployment

and test skin-spar-wing foam-payload bay interaction

Airframe Testing

103

Avionics Testing: FCS

• Autopilot-Software:– Set up and start basic “.fly” file in HORIZON– Watch the virtual mission take place in real

time (on-screen instruments)– Connect aircraft to HORIZON– Repeat above test, verify that servos are

moving properly during the test. • (Correct elevon mixing should be displayed)

– Check HORIZON vs STK-8 predicted and actual behavior

104

Avionics Testing: FCS• Autopilot-Navigation/Gain Adjustment (Ground

Launch, AFTER complete aircraft integration):– Fly in straight line, max distance in direction of launch– 90-degree “L” turn, max distance after one right-angle

turn– U-turn after launch, max distance away from launch

direction– “Z” turn, max distance after two opposite right angle

turns– Fly in straight line, circle about a waypoint (Ideally a

good thermal) for as long as possible– Pull-up maneuver– Adjust feedback loop gain and NP location as

necessary (moving batteries fore/aft)

105

• Autopilot- Hardware:– Measure and inspect MP2028 card to

determine: • Suitable mounting to avionics rack• Best routing of cables/wires/pitot-static lines• Best way to protect the autopilot from:

– Physical Damage (Landing and Parachute Deployment)– Radio Frequency Interference (if applicable)– Electrostatic Discharge (ESD) from EPP foam body

Avionics Testing: FCS

106

• Test (same for both batteries):– Charge time from zero to full– Full-discharge time under constant load at

65F (light bulb, heater, etc)– Full-discharge time of cold battery (dry ice

equilibrium temperature, ~ -40F)• This will help determine the maximum mission

duration at altitude, and quantify our battery safety factor

Avionics Testing: Batteries

APPENDIX VII: MANAGEMENT PLAN

108

Table of Contents• System Architecture• Mechanical Design Elements• Electrical Design Elements• Software Design Elements• Integration Plan• Verification and Testing• Management Plan• Appendix I: System Architecture• Appendix II: Mechanical Design Elements• Appendix III: Electrical Design Elements• Appendix IV: Software Design Elements• Appendix V: Integration Plan• Appendix VI: Verification and Testing• Appendix VII: Management Plan

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