Alabama A&M University

Rocket ProgramCDR Presentation

2011

Overview1. The Project Summary2. The Launch Vehicle3. The Scientific Payload4. Safety and Testing5. Rocksim Simulations6. Budget7. Outreach

Project Summary• We plan to design, fabricate and launch a reusable

rocket with scientific payloads.

• The scientific payload will measure the affect of altitude on the frequency response of a driver.

• The rocket should have a safe return with the help of the Dual Deployment Parachute system.

• The scientific payload should withstand the impact of landing and the data should be recoverable.

Launch Vehicle Summary

Size: Length = 7.5 ft, Diameter = 6 in

Motor: Aerotech 75 mm L-850W Solid Motor

Flight: The rocket should attain an altitude of 5280 ft ± 400 ft.

Recovery: Dual Deployment System

Changes Made Since PDR

• The material that is used on the launch vehicle is Magna Frame.

• The main parachute is a TAC-9A at 96”.

Launch Vehicle• The launch vehicle is constructed of Magna Frame tubing, which

has been selected over the traditional phenolic tubing due to more strength and lighter weight.

• A four fin design was used to decrease the amount of wind-induced spin, and to move the center of pressure toward the air frame.

• The launch vehicle is composed of the following five subsystems:1. Nose-cone & Payload2. Main Parachute Compartment3. Recovery Bay 4. Drogue Parachute Compartment5. Booster Section.

Parachute Housing

Main Parachute Compartment

Drogue Parachute

Recovery Systems

Dual Deployment Attachment Scheme

Typical Dual Deployment Setup

Avionics Bay & Altimeters

Recovery Bay Perfect Flite Altimeter

Dual Deployment Avionics Test

• With the altimeter armed, pull and release the balloon for barometric pressure.

• The LEDs lights should activate which signals from altimeter indicating no barometric pressure.

• Consists of balloon, cup, altimeter,

• LED lights, and 9V battery.

Spectrum Parachute Sizes

• We are estimating that the weight of the rocket will be between 20-25lbs.

• The size of the parachute will be based on the weight and a desired descent speed 17-22ft/s.

• The main parachute is a GLR Tac 9A parachute. The website info central has a descent rate calculator for determining the needed size.

• We can also change the chute sizes in Rocksim and verify the descent rate.

• The main parachute compartment will contain a parachute in the range of 24 to 30 inches.

• The drogue parachute compartment contains a 24 inch Tac 9 parachute.

Ejection Charge CalculationsAn ejection force of 10 psi. has been selected for ground testing. The Ideal Gas Law: PV = nRT

The Ejection Force (lb) : F= P*πr2

Where, P is the chamber pressure, psi, and r is the radius, in.

Black Powder (BP) CalculationsC * D2 * L = grams of BP

Where: C is a constant that is determined based on the pressure D is the airframe diameter L is the length of the body tube to be pressurized3.5 grams of black powder will be needed for Main and about 2 grams for

the drogue compartment. The back-up charges are increased by one gram for flight

Safety & Enviroment

Payload Summary• Measures frequency response

vs. altitude

• Portable Mp3 Player

• Powerful 15w amplifier

• Full range driver

• Omnidirectional Measurement Microphone

• PreAmp with Phantom Power

• Custom battery pack

•  Rocket Data-Acquisition System (R-DAS)

• Insulated ABS Container

Payload Summary

Payload Operation

• Pink noise used as reference signal

• Amplifier provides power to driver

• Microphone records driver response

• R-DAS stored microphone data digitally

• Driver response will be affected by air load on cone.

Payload Electronics• Battery Pack

• 12 1.2v 3600mAh batteries wired in series• Driver

• Peerless 3” Full range driver• Microphone

• Dayton EMM-6 Omnidirectional Measurement Microphone• Pre Amplifier

• MXL MicMate• Signal Source

• SanDisk Sansa Clip 1GB• Amplification

• Sure TA2024 Class D Amplifier• Transformer

• Automotive USB charger, adapted for payload usage• Data Storage

• Rocket Data Acquisition System (R-DAS) 

Payload Safety & Verification

Preliminary analysis of Failure Modes

Function Potential Failure Mode Potential Effects of Failure Failure Prevention

1 Battery Pack Malfunction Devices will not be powered.

A short may cause fire or explosion

Positive wire will be fused. Devices will be checked for

power.

2 Driver, amplifier, signal source, microphone, preamp malfunction

No or incorrect data will be obtain

Insure Proper Setup and operation, Check power

supply

3 R-DASMalfunction

Will not record data Check power and settings.

Rocksim Forecasting

Rocksim Forecasting

BudgetingComponents Cost Distributor

Structures & Launch System $ 2,400 Giant Leap

Aerotech

Tools $ 350 Home Depot, Lowes

Travel $ 500

Electronics $500 Madisound, Amazon, parts-express

Activities/Outreach $ 200

Paint & Body $ 150

Total $ 4,100

Outreach Summary

• Boys & Girls Clubs of Madison County

• School of Engineering and Technology Awareness Day

• Alabama A&M University - Science Technology Engineering & Mathematics (STEM) Day

• Alabama A&M University NASA High School Senior Day:

Questions?????