Transcript Tropos-1 Hybrid rocket Project

Seattle Central Community College, Seattle, Washington
Science and Math Department
2008-2009
Members: Colin Webb, Cooper Clausen, Luan Duong, Brian Injugu
Team organization
 Team lead: Colin Webb
 Electronic system: Cooper Clausen
 Recovery system: Luan Duong
 Logistics: Bryan Injugu
Project’s Goals
 To participate in 4th Intercollegiate Rocket Engineering Competition
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in Utah June 24th-27th, 2009.
The project is student led and researched.
The rocket must be constructed with a minimum amount of cost.
The rocket must clear the launch rail and reach an estimated altitude
of 10,000 ft.
The avionics must record data multiple times during flight and be
retrieved easily after flights.
The single state recovery system is controlled by avionics onboard the
rocket continuously.
The recovery system must land the rocket on the ground safely and in a
reusable condition.
Flight data including the peak altitude must be provided within 2
hours after recovery.
Propulsion System
 Homemade hybrid rocket engine using Hydroxyl
Terminated Polybutadiene (HTPB) as the solid fuel
and N2O as the oxidizer.
 Why hybrid? It’s a simple and easy to make engine
minimizing the overall cost of the rocket.
 Weight: 20 lbs N2O + 23 lbs HTPB
Igniters
 Homemade igniters
using black powder and
magnesium filings
 Nichrome wire heats up,
ignites black
powder/magnesium
filing mixture
Nozzle
 17-hole showerhead injecting nozzle allows proper
vaporization to the igniters.
 Graphite thrust nozzle cast directly to the solid fuel
grain
Oxidizer Tank and Plumbing system
 Reconditioned aluminum storage tank pressurized to 750
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psi
Radio controlled fuel plumbing system and fuel hose
ejection
Fuel ball valve connected to a radio controlled actuator
Contains 20 lbs of N2O
Estimated thrust is about 600 lb, provided the rocket an
initial acceleration of 3.7 G’s.
Recovery System
 Single stage deployment
 Electronically controlled by G-Wiz HCX
flight computer system.
 Auto-detected apogee chute release.
 Barometric and acceleration sensors provide accurate
apogee detection and precise chute release control.
 30 ft diameter military surplus parachute
 Spring loaded pilot chute deploys the main chute.
 Search radius is about 2 miles from the launch rail
Electronics Launch System
 Controlled by radio signals.
 Radio transmitter and receiver modules are TLP434A and
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RLP434.
Digital signal are encoded by an HT12E chip.
3-event digital signals including: to open or close valve gas,
and to eject the fuel hose.
A circuits which detects the orientation of the valve will fire
the igniters automatically.
4 power supplies to minimize supply decoupling issues
during design and testing phases.
Structure
 A simple structure of 3 aluminum U channels and 9-inch
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diameter plywood bulkheads.
Reinforced by more U channels, L brackets and riveted
together.
Solid fuel grain is attached by an aluminum casing and
reducer framing.
The body was reinforced by concrete form tubes.
Due to the lack of composite materials, lowing down the
weight is impossible.
As a result, we opted to forego having a payload and
attempt to launch the rocket as is.
Nose Cone
 Self-constructed nose cone was made from marine
type fiberglass laid around a mold and rounded at the
tip.
 Conical design chosen over ogive in the interest of easy
fabrication
 Construction road cone used as the mold
Fins
 Calculated dimension of the fins was obtained using
the Barrowman’s equations and a spreadsheet
calculator provided online
 3 fins spaced 120 degrees
 Constructed from
 Attached directly to engine housing
Launching Process
 Step 1: Fill the oxidizer tank with N2O
 Step 2: Move rocket to vertical launch position
 Step 3: Eject fuel line
 Step 4: Initiate fuel delivery / ignition
 Step 5: Main chute deployment just after apogee
 Step 6: Locate / Recover rocket on ground and retrive
altitude information
Possible Failure Points
 Will plumbing hold 750 psi?
 Will igniters create enough energy to ignite nitrous
oxide?
 Will injection nozzle vaporize fuel?
 Will thrust be sufficient to lift rocket off?
 Will thrust be sufficient to achieve altitude and
stability?
 Will G Wiz detect apogee?
 Will parachute deploy properly?