Sound Test - PowerPoint PPT Presentation

Sound test
1 / 49

  • Uploaded on
  • Presentation posted in: General

Sound Test. Testing and Integration of a Rocket-Launched Video Imaging Platform. IniTech Engineering. Apoorva Bhopale Susan Schmidt Rob Wingo Brian Love. 1 May 2002. Project Background. Project is sponsored by Applied Research Labs Main Objective:

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

Download Presentation

Sound Test

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Sound test

Sound Test

Testing and integration of a rocket launched video imaging platform

Testing and Integration of a Rocket-Launched Video Imaging Platform

IniTech Engineering

Apoorva Bhopale Susan Schmidt Rob Wingo Brian Love

1 May 2002

Project background

Project Background

  • Project is sponsored by Applied Research Labs

  • Main Objective:

    • Prove the validity of a rocket launched balloon as a telecommunications platform

  • Possible uses, disaster relief, drug interdiction, inexpensive “throwaway” satellites

  • Rocket is to be launched this summer

Overview of the presentation

Overview of the Presentation

  • Goals to accomplish

    • Description of each goal

    • Work completed for each goal

  • Future work

  • Questions

Semester goals

Semester Goals

  • Design and build payload canister with mountings for electronics

  • Size and build drogue chute

  • Test balloon buoyancy

  • Test Electronics

  • Test balloon deployment

Flight profile

Flight Profile

Chute sizing

Chute Sizing

Brian Love

Drogue chute

Drogue Chute

  • Required to deploy balloon after ejection

  • Will be used to slow descent after operations


Previous work concluded that a small chute will deploy the balloon

Limiting factors for design are descent constraints


Weight of payload


Allowable impact velocity



D = drag force

W = weight

ρ = air density

Cd = coefficient of drag

A = area

Vt = terminal velocity

r = chute radius

d = chute diameter

m = mass

g = gravitational





Standard Atmosphere

Chute design

Chute Design



Weight: 14.2 oz.

Balloon tilt

Balloon Tilt

  • Weight drop of 11 oz. from 25 to 14 oz.

  • Balloon used was ~1/4 scale

Neutral buoyancy

Neutral Buoyancy



Need mass air inside balloon

4kg less than the STP value

for neutral buoyancy

Temperature difference

Temperature Difference



  • Absorbed solar energy

  • Air circulation inside balloon

  • Descent rate of inflated balloon vs. chute

  • Thermal updrafts

  • Need experimental data to prove theoretical

  • Testing difficult on ground

Payload canister

Payload Canister

Susan Schmidt

Initial avionics canister design

Initial Avionics CanisterDesign

Canister made of 4.25 inch

PVC pipe

Covered in carbon fiber

Electronic components

secured with bubble wrap

Plexiglas bottom

for camera

Previous canister design changes

Previous Canister Design Changes

  • Components hit canister walls and each other

  • Bubble wrap was not sufficient vibration control

  • Foam was then used to secure items

Issues with past designs

Issues with Past Designs

  • Carbon fiber blocks radio waves

  • Electrical components not secure

  • Plexiglas fogs at higher altitude

  • Plexiglas cracks easily

  • Component constraints cannot handle temperatures of high altitudes

Requirements for the avionics canister

Requirements for the Avionics Canister

Structural integrity

Limit component vibration

Airtight seal

Temperature control

Structural integrity external material options

Structural IntegrityExternal Material Options

  • Metals

    • Possible Shrapnel

    • Weight

  • Porous materials, i.e. wood

    • Airtight seal

  • Plexiglas

    • Cracks easily

  • Lexan

    • High cost

    • Availability

      And the winner is…

Sound test


  • Weather Resistant

  • High strength to weight ratio

  • Corrosion Resistant

  • Good thermal insulator

  • Self-extinguishing

  • Low cost!!

Internal structure

High impact resistance

Used to stabilize internal components

Used for the camera viewing area

Internal Structure

Limit component vibration

Limit Component Vibration

  • Two 0.09” thick Lexan perpendicular


  • Secured components with nuts and bolts

  • Ends capped with hobby plywood

Airtight seal

Airtight Seal

  • Change in pressure from sea level to higher altitudes cause fogging on the Lexan

  • Seal end of canister with Teflon Tape

  • Teflon tape for extruding connections

  • Pump in Nitrogen through a gas fitting

  • Inert gas replaces the water vapor

Temperature control

Temperature Control

  • Camera’s operating range:

    -1.1°C to 37.77°C

  • Above 8,000 feet the temperature drops below this operating range

  • The rocket test in summer will not reach this altitude

  • The temperature limits of the components must be evaluated for higher flights



Rob Wingo

Electronic components

Electronic Components

  • Accelerometer board

  • GPS/Video Overlay board

  • GPS receiver

  • Video camera

  • Telemetry system

  • Batteries

Semester objectives

Semester Objectives

  • Connect all of components and make work

  • Range test telemetry system

  • Find problem with power source

  • Determine how to use accelerometer board as an event trigger

  • Mount electronics in canister

Component connectivity

Component Connectivity

  • Successfully connected all components

Range test first try

Range Test: First try

  • Unsuccessful

  • Assumed power problem

Range test second try

Range Test: Second try

  • Made adjustments to power supply and connectivity board

  • Still unsuccessful

Range test third try

Range Test: Third try

  • Re-soldered connectivity board

  • Still unsuccessful

  • Contacted transmitter manufacturer

  • Discovered range can be drastically reduced by ground effects

Ground effect problem

Ground Effect Problem

  • Transmitter designed for aerial use only

  • Will not be able to accomplish range test on ground

Balloon deployment

Balloon Deployment

Apoorva Bhopale

Balloon deployment1

Balloon Deployment

  • Objectives

    • Determine a method to pack the balloon

    • Determine an adequate amount of black powder to eject the canister

Balloon size

Balloon Size

Suggested method

Suggested Method

Pyrotechnic ejection

Pyrotechnic Ejection

  • Advantages

    • Reliable

    • Lightweight

    • Used extensively

Possible failure modes of the ejection

Possible Failure Modes of the Ejection

  • Too Little Black Powder

    • Does not clear ejection tube

      • Inhibits the rockets main chute deployment

      • Payload crashes with the rocket

  • Too much Black Powder

    • Rocket tube explodes

    • Drogue chute rips from balloon

    • Burnt drogue chute or balloon

Theory of pyrotechnic ejection

Theory of Pyrotechnic Ejection

  • Wp=Weight of Black Powder (lbs)

  • dP= Ejection Charge Pressure in Psi

  • V= Free volume in cubic inches

  • R= Combustion gas constant 22.16 ft- lbf/lbm-R

  • T= Combustion gas temperature, 3307 degrees R

Test footage

Test Footage

Conclusions from test

Conclusions From Test

  • Place Canister closest to the ejection charge

  • Use 7 grams of Black Powder



  • Design and build payload canister with mountings for electronics

  • Size and build drogue chute

  • Test balloon buoyancy

  • Test Electronics

  • Test balloon deployment

Future work

Future Work

  • Verify range of the transmitter another way

    • Possibly send it back to manufacturer

  • Test the deployment method in a rocket

  • Determine a way to sever connection between balloon and canister

  • Neutral Buoyancy test

  • Setup accelerometer board to be used as event trigger


Dr. Ronald Stearman

Dr. Martin Barlett

Dr. Jennifer Lehman

Danny Linehan

Daniel Parcher

Rick VanVoorhis

Lixin Gong




  • Login