Second General Body Meeting
September 27, 2013

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Energy Research and Education Park
Sugar Motor Demonstration
CanSat Details
Rocketry Basics and Structures

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Off-campus facility for the Rocket Team
Our own office
Shared manufacturing space
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Drill Presses
Table Saw
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Circular Saw
Belt Sander
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Hand Tools
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Hardware
Where we store rockets and equipment

2701 SW 23rd Terrace, Building 241

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Thursday, Oct. 3 rd , at 6:00
Energy Park
 Jimmy Yawn
( www.jamesyawn.net
)
 Make and test some propellant

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Target Altitude: 1000 ft.
Payload Specifications
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0.5-1.1 kg
Cylinder
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63.5 mm diameter
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About 122 mm high
Recoverable (Dedicated Parachute)
H class motor
Sketches/OpenRocket
Lauren’s email: lekrueger@ufl.edu

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3 rd GBM
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Thursday, October 10 th , 6:15 PM
Little 0121
Lessons
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Propulsion
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Flight Dynamics
Recovery
SpaceX info session
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10/1, 6:15, Little 109
Rocket team interns
Career Showcase
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10/2, O’Connell Center

B R I T T N E Y L A N E
L E A D S T R U C T U R E S E N G I N E E R

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Apogee- the highest altitude that the rocket reaches in its ascent
Drag- the force that resists the motion of the vehicle through the air and opposes thrust; due primarily to friction between the surface of the vehicle and the fluid through which it travels, air
Thrust- upward force generated by motor
Center of Gravity (CG)- Point at which you can balance the rocket on one finger. The rocket rotates around this point during flight.
Center of Pressure (CP)- Point at which all of the forces
(Drag, Thrust, Lift) can be realized as one point. The sum of all of the forces acting on the rocket occurs at the center of pressure.

Building a Rocket:

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Very important for aerodynamics; design to reduce drag
Drag is related to the surface area of the nosecone and velocity
Different shapes of nosecones:
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Ogive (most common)
Parabolic
Cone
Attached to parachute
Use lightweight material like plastic

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Cylindrical body of rocket that houses the parachutes, avionics bay, payload bay, motor and more
Length and weight affect flight performance
Use durable but lightweight materials: plastic, Blue
Tube, phenolic tubing, etc

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Houses all the electronics of the rocket
Located between two bulk heads
Must be easily accessible for quick repairs or rewiring
Secured to airframe with screws or shear pins

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Add to stability of rocket
Typically 3-4 fins
Lightweight and durable materials (wood, G-10 fiberglass)
Usually attached to body with epoxy
Many different shapes:
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Trapezoidal
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Triangular irregular

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Motor tube made of stiff cardboard is secured inside of body tube with epoxy between centering rings.
Motor tube holds the motor in the rocket safely and keeps it centered. Transfers thrust from motor to rocket.
The motor is kept from falling out of the rocket after burnout with screws, hooks, caps, etc.

Building a Rocket:

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Consider the purpose of your rocket and what it must hold to determine the minimum length and size
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Ex. Satellite or quadcopter inside, 4 ft diameter parachute, 20 ft of shock cord
Consider cost constraints in selecting materials or designing parts that need to be manufactured

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Stability Margin =
(Distance between CG and
CP)/(Body Tube
Diameter)
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<1 : Under stable
1-3 : Good range for model rocketry
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>3 : Over stable
CG is above CP

Open Rocket
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Free software
Helpful in determining stability and testing rocket with different motors
Solidworks
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Used to design parts to be manufactured in the shop
To create a detailed full-scale model

Building a Rocket:
OTHER USEFUL PARTS

 Used to separate sections of the rocket (payload bay, avionics bay, etc)

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To center the motor tube in the body of the rocket
Used to secure motor tube in place so that thrust is transferred from the motor to the rocket

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Used to put the rocket onto the launch rod
Keeps the rocket on a straight, controlled path during lift off

Building a Rocket:
MACHINES AND TOOLS

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Used for cutting fins, making slots in body tube, cutting motor tube, etc
Safety:
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Wear safety glasses
Do not wear gloves or loose clothing
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Wait until the blade stops moving before removing your work piece
Make straight cuts only

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Used for drilling holes, cutting out bulkheads, centering rings, etc
Safety:
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Wear safety glasses
Do not wear gloves or loose clothing
Wait until the bit stops spinning before removing or inspecting your work piece

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Used for sanding down fins, smoothing edges, adjusting bulkheads/centering rings, etc
Safety:
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Wear safety glasses
Do not wear gloves or loose clothing
Wear mask so as not to inhale particles for certain materials
Keep your hand at a safe distance from the sander
Turn it off when you finish

The Flight:
PHASES AND EVENTS

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Powered Ascent – Rocket is being forced upwards by the motor’s thrust force.
Unpowered Ascent
(coast) – Rocket continues upward due to its vertical momentum. Motor is no longer burning.
Descent – Rocket has separated and is now falling to the ground at a much slower rate due to the deployment of parachutes.

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Lift- relatively small force
(since the flight is almost vertical); generated by the fins
Weight- depends on materials and construction
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F g
= mg
Drag- the force that resists the motion
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F
D
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= (1/2)ρv 2 C
D
A
ρ= density of fluid
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 v = velocity
C
D
= drag coefficient
A = area
Thrust- upward force generated by motor; depends on motor choice