PowerPoint Presentation

University of Florida Rocket Team Third General Body MeetingOctober 10, 2013

1Todays MeetingProject UpdatesDesign OpportunitiesOffice HoursPresentationsMotor BasicsOpenRocketRecoveryHybrid CompetitionPropulsions ResearchBringing 8 teamsSix highest altitudeTwo 2,000 feetMeeting yesterday

Sugar MotorsPotential launch

Updates

Were bringing 8 teams, which is awesome. Most other schools are bringing like 2-3 (8 other Universities around Florida competing)Ask Kyle about meeting yesterday

Sugar motors. Down the grain. After a static motor test3Static Motor Test StandVariable motor diameter24mm-98mmWithstand 3000 N with reasonable factor of safetyOperate upwards and downwardsMeasure force over time (load cell)Clamp into ground.

4Static Motor Data AcquisitionLabVIEW VI Measure and interpret data from the load cellNI DAQ (OOTB or 6009)

Needs to determineTotal ImpulseAverage ThrustMax ThrustThrust CurveBurn Time

5Fin Mount ApparatusApparatus to help mount fins symmetricallyMultiple rocketsEither 3 or 4 finsMultiple body diameters/motor mount tubesAccount for changing location of centering rings

6Office HoursMAE A 211

Monday, 9:30 AM 12:00 PMTuesday, 2:30 4:00 PMFriday, 9:30 AM 12:00 PM

7Basics of Rocket motorsPropulsionHow Rockets WorkNewtons Third Law of Motion:For every action there is an equal and opposite reaction

Rocket motor = energy conversion device- Matter (solid or liquid) is burned, producing hot gases.- Gases are accumulated within the combustion chamber until enough pressure builds up to force a part of them out an exhaust port (a nozzle)- Thrust is generated by a pressure buildup within the combustion chamber and by mass ejection through the nozzle.- Combustion chamber geometry, throat diameter, and nozzle geometry govern performance and efficiency (Conservation of Momentum-Fluids)

Different Types of Motors

Solid Motor Basics

Bates GrainsRocketryModel RocketryUses motors A-GAnyone can launchClass 1Is made of paper, wood, or breakable plasticUses a slow burning propellantHigh Powered RocketryNeeds certificationsUses motor more than 160 N-seconds of total impulseUses motor more than 80 N average thrustExceeds 125 g of propellantUses hybrid motorRocket weighs more than 1500 g Includes any airframe parts of ductile metalClass 2High Powered RocketryLevel CertificationsLevel 1- Uses H (320 N-seconds) or I motors (640 N-seconds)Level 2- J, K, LLevel 3- M, N, OBeyond O is Class 3 and requires waivers (total impulse greater than 40,960 N-seconds)Numbers of MotorExample H64-8 H is the total impulse (between 160-320 N-s)64 N is the average thrust8 seconds is the delay ejection chargeTo determine motor burn divide total impulse by average thrustIntroduction to flight DynamicsOpenRocketAn Introduction to the recovery subsystemRecoveryRecoveryA reliable system to safely land the rocket.

Must be reusable without repairs.

GoalConsistently return a rocket to the ground without damage to the rocket or objects on the ground.Critical for continued testing of payload

Possible DesignsFeatherweight RecoverySmall rocketsFlutter downTumble RecoverySystem induces tumbleNose-Blow RecoveryNosecone induces tumbleParachuteEjected from rocketIncreases dragGlide RecoveryAirfoil deployed

Possible Designs ContinuedHelicopter RecoveryBlades deployedRocket autorotates

Dual Deployment

Rocket undergoes powered and unpowered ascensionAscensionDuring ascension rocket naturally orients itself into windDrifts an amount up range depending on wind speed

Altimeter detects apogee and sets off ejection charges. The nose cone is ejected and the drogue parachute is deployedApogeeApogee is highest point the rocket attainsApogee is detected by the altimeterAltimeter controls the ejection charges

Ejection chargesForces the shear pins to break and deploys the drogue parachuteE-fuses are detonated by the altimeterCharge TypesBlack Powder SubstitutesCO2 Canister

Charge Testing

Drogue parachuteSmaller X-Form ParachuteSufficiently lowers the speed without a large horizontal driftDeployed at apogee

Selecting parachute sizeFD = (r)(Cd)(A)v2FG= mg

FD=FG(r)(Cd)(A)v2=mgA=D2/4

D = sqrt( (8mg) / (*r*Cd*v2) )

V= sqrt( (8 m g) / (*r*Cd*D2) )

Cd=Coefficient of Dragr=density of airv=velocity

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At a preset attitude, around 700ft, the second ejection charge will deploy the main parachute Main ParachuteDetonated by the altimeter at a specified altitudeAlso uses ejection charges to deployAllows for a much slower descent rate

Rocket is located and recoveredLocating the rocketTransmits GPS coordinates to locate the landed rocket

MeetingBegin the design phase of the recovery sub-systemFriday Oct, 115:00PM Library West Room 230

Upcoming MeetingsPropulsions ResearchRight here, right now (brief)CanSatsTuesday, Oct. 15, 6:30 at the Energy ParkGBMThursday, Oct. 24, 6:15 in Little 121