Yough Cougar Rocketry TeamYough Cougar Rocketry TeamHerminie,

Pennsylvania

Project Dorothy

NASA SLI 2008

Critical Design Review

Herminie, Pennsylvania

Project Dorothy

NASA SLI 2008

Critical Design Review

Amy Rene’ BickerstaffAmy Rene’ BickerstaffTeam Lead

Vehicle DesignScheduling Manager

Ashley WileyAshley Wiley

NAR & FAA RegulationsFlight Control

Payload

Stephanie AbbottStephanie AbbottSafety Operations Manager

Josh SarosinskiJosh Sarosinski

Hazardous MaterialsEnvironmental Concerns

RockSim Drawing of Dorothy II

The center of gravity is located 11 inches aft of the coupler. This design is to allow a helicopter style descent rather thana ballistic trajectory in the event of recovery failure.

Currently there is a 4.97 caliber level of stability.No wobble has been detected in smaller scale test launchesthus far, which should indicate successful flight of the full scale design.

General Assembly of Dorothy II

General Arrangement of

Dorothy II

Outline of Dorothy II

Thrust Data for L1150

Thrust data for L900RR

Launch Rail Exit Velocities

Launch Rail Exit Velocities

• The Aerotech L1150 motor• 48.9 ft/sec

• Animal Motor Works L900RR• 35.65 ft/sec

• The Aerotech L1150 motor• 48.9 ft/sec

• Animal Motor Works L900RR• 35.65 ft/sec

The L1150 provides a sufficient velocity to ensurestable flight from a 60 inch rail. The L900RR would need a 90 inch rail to achievea desired rail exit velocity of 44 ft/sec.

Descent Rate of Dorothy II

Descent Rate of Dorothy II

• Classic 60 SkyAngle Parachute• 30.06 ft/sec

• Large SkyAngle Cert - 3 Parachute• 24.31 ft/sec

• XL SkyAngle Cert - 3 Parachute• 17.12 ft/sec

• Classic 60 SkyAngle Parachute• 30.06 ft/sec

• Large SkyAngle Cert - 3 Parachute• 24.31 ft/sec

• XL SkyAngle Cert - 3 Parachute• 17.12 ft/sec

Data gathered fromhttp://www.onlinetesting.net/cgi-bin/descent3.3.cgi

Ejection Charge TestEjection Charge Test• 4 inch tubing with aluminum bulkplate

• Glow plug ignition

• 4 inch coupler, 4 inches in length with bulkplate to form piston

• Attached to the aluminum bulkplate with stainless steel cable• Stainless steel cable cut to a length to prevent piston ejection from

tube

• 4 inch coupler, 30 inches in length to mimic sabot

• Will impact nosecone bulkplate

• Test nosecone created

• 4 inch tubing with aluminum bulkplate• Glow plug ignition

• 4 inch coupler, 4 inches in length with bulkplate to form piston

• Attached to the aluminum bulkplate with stainless steel cable• Stainless steel cable cut to a length to prevent piston ejection from

tube

• 4 inch coupler, 30 inches in length to mimic sabot

• Will impact nosecone bulkplate

• Test nosecone created

Ejection Charge AmountEjection Charge Amount• 20 psi desired inside airframe• Piston style ejections use less powder• Equation shows only .64 grams of

powder required to eject • CDR Recovery Subsystem

• Multiple tests to ensure proper ejection

• 20 psi desired inside airframe• Piston style ejections use less powder• Equation shows only .64 grams of

powder required to eject • CDR Recovery Subsystem

• Multiple tests to ensure proper ejection

Ejection Test ProcedureEjection Test Procedure• Slide piston into airframe• Measure 1 gram of 4Fg powder• Pour powder into chamber• Insert chamber into airframe• Insert coupler tube into airframe• Install nosecone by attaching U-bolt• Secure test apparatus• Energize glow plug

• Slide piston into airframe• Measure 1 gram of 4Fg powder• Pour powder into chamber• Insert chamber into airframe• Insert coupler tube into airframe• Install nosecone by attaching U-bolt• Secure test apparatus• Energize glow plug

Ejection Charge TestingEjection Charge Testing

Ejection Charge TestingEjection Charge Testing

The piston design proved to be very successful.Using 1 gram of 4Fg powder, the nosecone wassent about 20 feet into the yard. The only issuediscovered was that the bulkplate in the pistonseparated from the tubing. This will be correctedby using HP-20E Hysol epoxy rather than the slow cure CA glue.

1/4 Scale Test Flight

» Click the link to view the video of the test launch. Windows Media Player

» Windows Media Player of Quarter Scale Dorothy Rocket

QuickTime Video File» Apple QuickTime of Quarter Scale Dorothy Rocket

» Click the link to view the video of the test launch. Windows Media Player

» Windows Media Player of Quarter Scale Dorothy Rocket

QuickTime Video File» Apple QuickTime of Quarter Scale Dorothy Rocket

Notes from Scale Launch

Quest A6-3 motor used10 - 15 mph winds, gusts to 20 mphNearly perfectly vertical flight during

the thrust portion of the flightVery little drift during coast phase Ideal launch considering a low thrust

motor was selected

Deployment System

• PerfectFlight LC800 Dlx Altimeters– Dual Event Logging– Ejection at Apogee via pressure sensor– Main ejection at 800 feet – One powder charge with two E-matches– Piston pushes Sabot with parachute– Sabot peels away

• Still retained by kevlar chord• All pieces remain attached to the launch vehicle

Electronics

Sabot Ejection System

• Fiberglass coupler cut in half to form sabot• Fiberglass bulkplate, hinged in the center to allow

sabot opening• Forward portion of sabot impacts nosecone bulkplate

upon ejection sheering the nylon pins• SkyAngle parachute begins to deploy• Whirlybirds begin to disperse when sabot peels back• Payload protective bags not required

– May still be used to eliminate burning of parachute

Payload Integration

• Split Sabot contains all payload– Whirlybirds placed along main axis– Main parachute above whirlybirds

• Upon ejection, sabot opens to release parachute and whirlybirds

• No payload protection required as piston contains ejection gases

• Odd shaped items work easily inside sabot since they do not need to slide up the airframe for ejection

Community OutreachCommunity Outreach

Computer Refurbishing and Sales Computers saved from landfills Community can purchase internet ready computers at

very low cost Chinese Auction

Items donated from Pittsburgh Steelers, Pirates, and Penguins

Seven Springs Mountain Resort Giant Eagle Food store Westmoreland Mall

Westinghouse Display during lunch Funding

Computer Refurbishing and Sales Computers saved from landfills Community can purchase internet ready computers at

very low cost Chinese Auction

Items donated from Pittsburgh Steelers, Pirates, and Penguins

Seven Springs Mountain Resort Giant Eagle Food store Westmoreland Mall

Westinghouse Display during lunch Funding

Funding IssuesFunding Issues Student Outreach Drastically Modified

Quest Starhawk rockets to be given away during Chinese Auction sale days

Rocket Fair to pick prizes and launch rockets

$ 3780 raised selling computers $ 1500 for candy sales Are we going to make it ???

Student Outreach Drastically Modified Quest Starhawk rockets to be given

away during Chinese Auction sale days Rocket Fair to pick prizes and launch

rockets $ 3780 raised selling computers $ 1500 for candy sales Are we going to make it ???

SLI Grant moniesSLI Grant monies

$1250 SLI grant uses ( all gone !!! ) Purchase Quest Starhawk rockets

$ 300 Purchase Quest Flight Packs for

launches $ 177

Replacement Parts lost during SLI 2007 Over $ 500 so far

FedEX fees for shipping $ 300

$1250 SLI grant uses ( all gone !!! ) Purchase Quest Starhawk rockets

$ 300 Purchase Quest Flight Packs for

launches $ 177

Replacement Parts lost during SLI 2007 Over $ 500 so far

FedEX fees for shipping $ 300

Exit 8 - Huntsville

» Huntsville Trip in April» Trip Total estimated to be - $ 6875

» Airfare - $275 per ticket - $ 2750 total» Lodging - $425 per room - $ 2125 total» Meals - $200 per person - $ 2000 total

Looking into the Future

Complete construction of Dorothy II

Perform ejection charge testing

Continue analysis of whirlybird flight

Attempt construction of Data Ball

Launch 66% scale version with payload

Continue fundraising efforts

In ClosingIn Closing

Great Progress has been madeLearned from last year

New members working wellMore is being accomplished

Improved design of deploymentPiston / Sabot ejection system

Money is an issueFunding changes need addressed

Keep working hardRewards are coming soon

Thank youNASA’s MSFC makes it happen

Great Progress has been madeLearned from last year

New members working wellMore is being accomplished

Improved design of deploymentPiston / Sabot ejection system

Money is an issueFunding changes need addressed

Keep working hardRewards are coming soon

Thank youNASA’s MSFC makes it happen