Hybrid Competition Propulsions Research Bringing 8 teams Six
highest altitude Two 2,000 feet Meeting yesterday Sugar Motors
Potential launch Updates
Slide 4
Static Motor Test Stand Variable motor diameter 24mm-98mm
Withstand 3000 N with reasonable factor of safety Operate upwards
and downwards Measure force over time (load cell) Clamp into
ground.
Slide 5
Static Motor Data Acquisition LabVIEW VI Measure and interpret
data from the load cell NI DAQ (OOTB or 6009) Needs to determine
Total Impulse Average Thrust Max Thrust Thrust Curve Burn Time
Slide 6
Fin Mount Apparatus Apparatus to help mount fins symmetrically
Multiple rockets Either 3 or 4 fins Multiple body diameters/motor
mount tubes Account for changing location of centering rings
Slide 7
Office Hours MAE A 211 Monday, 9:30 AM 12:00 PM Tuesday, 2:30
4:00 PM Friday, 9:30 AM 12:00 PM
Slide 8
BASICS OF ROCKET MOTORS Propulsion
Slide 9
How Rockets Work Newtons 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)
Slide 10
Different Types of Motors
Slide 11
Solid Motor Basics
Slide 12
Bates Grains
Slide 13
Rocketry Model Rocketry Uses motors A-G Anyone can launch Class
1 Is made of paper, wood, or breakable plastic Uses a slow burning
propellant High Powered Rocketry Needs certifications Uses motor
more than 160 N-seconds of total impulse Uses motor more than 80 N
average thrust Exceeds 125 g of propellant Uses hybrid motor Rocket
weighs more than 1500 g Includes any airframe parts of ductile
metal Class 2
Slide 14
High Powered Rocketry Level Certifications Level 1- Uses H (320
N-seconds) or I motors (640 N-seconds) Level 2- J, K, L Level 3- M,
N, O Beyond O is Class 3 and requires waivers (total impulse
greater than 40,960 N-seconds) Numbers of Motor Example H64-8 H is
the total impulse (between 160-320 N-s) 64 N is the average thrust
8 seconds is the delay ejection charge To determine motor burn
divide total impulse by average thrust
Slide 15
INTRODUCTION TO FLIGHT DYNAMICS OpenRocket
Slide 16
AN INTRODUCTION TO THE RECOVERY SUBSYSTEM Recovery
Slide 17
A reliable system to safely land the rocket. Must be reusable
without repairs.
Slide 18
Goal Consistently return a rocket to the ground without damage
to the rocket or objects on the ground. Critical for continued
testing of payload
Slide 19
Possible Designs Featherweight Recovery Small rockets Flutter
down Tumble Recovery System induces tumble Nose-Blow Recovery
Nosecone induces tumble Parachute Ejected from rocket Increases
drag Glide Recovery Airfoil deployed
Slide 20
Possible Designs Continued Helicopter Recovery Blades deployed
Rocket autorotates
Slide 21
DUAL DEPLOYMENT
Slide 22
Rocket undergoes powered and unpowered ascension
Slide 23
Ascension During ascension rocket naturally orients itself into
wind Drifts an amount up range depending on wind speed
Slide 24
Altimeter detects apogee and sets off ejection charges. The
nose cone is ejected and the drogue parachute is deployed
Slide 25
Apogee Apogee is highest point the rocket attains Apogee is
detected by the altimeter Altimeter controls the ejection
charges
Slide 26
Ejection charges Forces the shear pins to break and deploys the
drogue parachute E-fuses are detonated by the altimeter Charge
Types Black Powder Substitutes CO2 Canister
Slide 27
Charge Testing
Slide 28
Drogue parachute Smaller X-Form Parachute Sufficiently lowers
the speed without a large horizontal drift Deployed at apogee
Slide 29
Selecting parachute size FD = (r)(Cd)(A)v 2 FG= mg FD=FG
(r)(Cd)(A)v 2 =mg A=D 2 /4 D = sqrt( (8mg) / (*r*Cd*v 2 ) ) V=
sqrt( (8 m g) / (*r*Cd*D 2 ) ) Cd=Coefficient of Drag r=density of
air v=velocity
Slide 30
At a preset attitude, around 700ft, the second ejection charge
will deploy the main parachute
Slide 31
Main Parachute Detonated by the altimeter at a specified
altitude Also uses ejection charges to deploy Allows for a much
slower descent rate
Slide 32
Rocket is located and recovered
Slide 33
Locating the rocket Transmits GPS coordinates to locate the
landed rocket
Slide 34
Meeting Begin the design phase of the recovery sub-system
Friday Oct, 11 5:00PM Library West Room 230
Slide 35
Upcoming Meetings Propulsions Research Right here, right now
(brief) CanSats Tuesday, Oct. 15, 6:30 at the Energy Park GBM
Thursday, Oct. 24, 6:15 in Little 121