BIG BLUE Satellite

Program

A High Altitude Inflatable -Winged Aircraft

Baseline Balloon

Inflatable Launch

Glider Unmanned

Experiment

BIG BLUE Satellite

Program

Core Team• Student team leaders

– Justin Kearns, Overall Team and Mechanical Engineering Technical Lead

– Mike Carter, Project Manager

– Aaron Welch, Electrical Engineering Technical Lead

• Advisors– Dr. Suzanne Weaver Smith, Principal Investigator and System Integration

– Dr. Jamey Jacob, Aeronautics

– Dr. William Smith, Communications and Power

– Dr. James Lumpp, Flight Control and Power

• Sponsors– National Space Grant Consortium via Kentucky Space Grant Consortium

– NASA EPSCOR

– ILC Dover, Inc.

– UK VP of Research

BIG BLUE Satellite

Program

The General Plan

• Phase 1 and 2: 1.5 hour ascent at a constant rate • Phase 2 begins prior to balloon release

• Phase 3: 2.5 hour descent

BIG BLUE Satellite

Program

Motivations• Low density (low Re) aircraft

- High altitude defense- Marscraft

• To overcome this challenge: larger wing span• Problem: costly to launch such large structures• Solution: Inflatable wings

BIG BLUE Satellite

Program

ILC Dover • Design and development of softgoods products for both

government and industry

• Experienced NASA contractor

– spacesuit design

– flexible space structures

BIG BLUE Satellite

Program

CU Balloon Launch

• Edge of Space Sciences (EOSS)

– a Colorado based non-profit

organization that explores frontiers in

amateur radio and high altitude

ballooning

BIG BLUE Satellite

Program

Project Time-Line • October 2002 - core team formed, grant awarded, ILC Dover, Inc. visit

• November 2002 - balloon launch in Colorado

• December 2002 - wing design completed, control system design completed and tested

• January 2003 - NASA Langley, Wallops Island, UAT & NASA Marshall visits

• February 2003 - Final verification tests

• March 2003 - Critical Design Review, 1st Flight Readiness Review, 1st BIG BLUE Satellite launch

• May 2003 – 2nd Flight Readiness Review, 2nd BIG BLUE Satellite launch

• August 2003 - flight data reduction and analysis

BIG BLUE Satellite

Program

Balloon Launch Basics

• Density and pressure drop

exponentially

– 30 km: alt=sl/60, Palt=Psl/100

• Temperature drops linearly in

the troposphere, then stabilizes

in the stratosphere until

increasing again

BIG BLUE Satellite

Program

High Altitude Conditions

BIG BLUE Satellite

Program

Team Organization

Wing Design Flight Control I Flight Control II Wing Deployment

Data AcquisitionRF/Digital

CommunicationsPower Autopilot Electronics

Structural / Integration

Launch / Recovery Outreach Risk Mitigation

BIG BLUE Satellite

Program

Wing Design (X-foil)

• Aerodynamic analysis

– X-Foil software

– Conduct analysis under:

• Low Reynolds number

– 50,000 ~ 200,000

• Various angles of attack

– Lift and Drag coefficients

obtained determine performance

– Pressure distribution may then be

established

BIG BLUE Satellite

Program

Wing Design (Airfoil Selection)

• Five different airfoils were

selected based on efficiency

of airfoils under low-

Reynolds number conditions

and analyzed using X-foil.

(dae11, dae31, e387, e398 and

s7012).

• After these were examined by

ILC Dover, airfoil e398 was

selected based on

manufacturability.

BIG BLUE Satellite

Program

Wing Design (ANSYS)

• Finite element analysis– ANSYS 6.1 software

– “Bumpy” airfoil coordinates were

provided by ILC

– Pressure distributions obtained from

X-Foil were applied on the top and

bottom surfaces

– Wing material modeled as cured

– Static and Modal analyses were

performed

– Objective was to determine the

maximum stress to define the number

of composite layers

BIG BLUE Satellite

Program

Wing Design (Prototype)

• UK Rapid-Prototyping lab created (using stereo-lithography) the two types of wing test sections for the selected airfoil

BIG BLUE Satellite

Program

Wing Design (Test setup)

• Prototypes will then be tested in the UK low-turbulence wind tunnel

• Tunnel test section: 24” x 24” cross section and 48” length

• 50-hp motor drives 50 m/s with free-stream turbulence levels less than 1/2%

• additional wind-tunnel with smaller test section (8” x 16”) and lower velocity (35 m/s) is also available

BIG BLUE Satellite

Program

Wing Design (Verification)• X-foil verification for other airfoils (e387 and

s7012) was first accomplished using wind

tunnel test data available from UIUC– UIUC conducts low-speed airfoil testing (data found

at http://www.aae.uiuc.edu/mselig/uiuc_lsat.html )

• Wind tunnel tests of our smooth e398 airfoil

will be compared to X-foil data to verify our

testing process

• Wind-tunnel tests of the bumpy airfoil will then

be conducted and compared to the ideal section

• One question to be resolved is loss at the

trailing edge

BIG BLUE Satellite

Program

Flight Control I

• Who? Fall 2002 ME 412 group

• Autonomous Flight Control via

a closed loop feedback control

system

– Information System: GPS and

Gyroscopic Feedback

• Microprocessor Controller to

Control Attitude and Flight

Path

• Low altitude verification tests

via rigid wing glider

BIG BLUE Satellite

Program

Flight Control I

• Autonomous flight capability:

MP1100 control system

– central microprocessor

integrates accelerometers,

gyroscopes, an altimeter, a pitot

tube, and GPS

– components allow capability of

airspeed hold, altitude hold, turn

coordination, and GPS

navigation

BIG BLUE Satellite

Program

Flight Control I

• Control System Components

Control SystemMicroprocessor

GPSGyros &

Accelerometers

Speed(Pitot Tube)

Altimeter

ServoMotors

SpeedController

Motor &Prop

RxReceiver

TxRc Controller

ControlSurfaces

BIG BLUE Satellite

Program

Flight Control I

• MP1100 offers versatile

programming options

– numerous configurations

accessible through onboard flash

memory

• Capable of multi-routine program

loops

• Emergency or failsafe routines

• PID loops and adjustable gains

BIG BLUE Satellite

Program

Flight Control II

• Who? Spring 2003 ME 412 group

• Low altitude Micropilot testing

• Integrating UK Autopilot into BIG BLUE aircraft

• UK Autopilot low altitude testing

• Meet payload constraints (power and weight)

BIG BLUE Satellite

Program

Wing Deployment

• Who? Spring 2003 ME 412 group

• Inflatable tube deployment

simulation

– Analytically predicts tube

deployment sequence

• Plenum design and inflation

method

• Meet payload constraints (power

and weight)

• Thermal vacuum chamber

verification tests

BIG BLUE Satellite

Program

Wing Deployment • Vacuum chamber testing to explore expansion methods

BIG BLUE Satellite

Program

Data Acquisition

• Who? Spring 2003 ME 412 group

• Instrumentation and data acquisition

– Cameras

– Environmental condition measurements

– Flight performance

• Meet payload constraints (power and

weight)

• Equipment calibration

• Ground testing

BIG BLUE Satellite

Program

RF/Digital Communications

• Who? Spring 2003 EE 499 group

• Communication of control signals and

data; APRS/GPS System interface

• Verification tests

– Temperature

– Moisture

• Meet payload constraints (power and

weight)

• Integration and testing

BIG BLUE Satellite

Program

Power

• Who? Spring 2003 EE 499 group

• Verification, temperature tests

• Develop power budget – set constraints for other subsystems

• Integrated effort with inflation and data acquisition

BIG BLUE Satellite

Program

Flight Control Sensors/Programming

• Who? Spring 2003 EE 587 group

• Design, build autopilot based on MicroPilot design– AHRS unit: gyros and sensors for roll, pitch, yaw heading

– Crossbow is a possible purchase

• GPS certification to top speeds above 60k feet

• AHRS, APRS, GPS interface

BIG BLUE Satellite

Program

Structural/Integration

• Who? Spring 2003 ME 380 group

• Planform design• Fuselage

• Wing mounting

• Internal mounting hardware and

orientation, abort parachute

• Manipulate component placement for

optimal C.G.

• Overall tracking of payload weight budget

• Tail control surfaces

• Meet payload constraints

BIG BLUE Satellite

Program

Launch/Recovery

• Volunteer opportunities:

– Critical Design Reviewers

– Flight Readiness / Safety Reviews

– UK BIG BLUE website design

– Tracking interface to “watch” flights

• Lat/Long coordinates

• Altitude data packets

• Live camera feed

– www.findu.com

BIG BLUE Satellite

Program

Risk Mitigation

• Volunteer opportunity

• Risk identification

• Likelihood and severity ranking of risks

• Development of solutions and verification tests in order to alleviate these risks

• Examples:– Premature rigidization of wings

– Batteries die early

– Transceiver malfunctions as a result of low temperatures

BIG BLUE Satellite

Program

Outreach

• Volunteer opportunity:

– BIG BLUE t-shirts

– E-Day demonstrations and

exhibit booth

– Talks to K-12 schools; science

fun days, etc.

BIG BLUE Satellite

Program

Overall Objectives

• Fall 2002

– Flight control verification

• Design and build rigid wing glider

• Test at low altitude

– Inflated wing design completed

• Spring 2003

– Establish remaining subsystem teams

– Design and build high altitude system

– Verification testing

– Balloon launch (late March – early May 2003)

– Data reduction and analysis through August 2003