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MonopropellantMicroPropulsionsystemfor

CubeSats

ByChrisBiddy

174SuburbanRdSuite120

San

Luis

Obispo

CA

93401(805)5498200

chris@stellarexploration.com

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Introduction

HighPerformanceCubeSatPropulsionwillopenupmany

opportunities

Decouplingofsecondarypayload(CubeSat)withprimarypayloadorbit Quickdeploymentofglobalconstellations

Goalistodevelop1Upropulsionsystemtobeintegratedin

3U

satellite

3UCubeSatwithdescriptionforeachunit

Propulsion

Unit

Electronicsandbatterysection

PayloadSection

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WhyMonopropellant?

Significantlyhigherperformance(deltaV)comparedtocoldgas

LargerThrustvs.ElectricPropulsion

NeededforOrbittransfer

Mature

technology Hydrazineisaknownandmaturehazard

NewGreen

propellantsstillrequireanalysisforrangesafety

Less

complicated

than

Bipropellant Twoseparatetankandplumbingsystemsforfuelandoxidizer

MorevolumeefficientthanBipropellant

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Requirements

MeetCubeSatStandard

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DesignPhilosophy

StartwithCOTScomponents

Test

and

modify

if

necessary/possible Simplify

StartwithThrustervalveanddesignaroundit

Developcubictankandcylindricaltankstructurepaperdesigninparallel

Comparetheoreticalperformanceofeach

Continuedesignwithbesttheoreticalperformance

Safetytopersonnelishighestpriority

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MicroPropulsionDetails

Miniaturesolenoidvalveusedfor

thrustervalve

2portdesignwitha#1032threaded

interface

Mass=37g

Maxoperatingpressure=110psi

(758kPa)

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MicroPropulsionUnit

Attachment

Point

foradditionalUnits

PropellantTank

PPODGuideRails

DrainandFillValves

(Schrader)

ThrusterCombustion

ChamberandNozzle

Thruster

Micro

SolenoidValves

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PropulsionSystemDetails

CNCmachinedtankandcap

PPODrailsintegratedintotankstructure

MountingFlangeprotrudes6.5mmfromtankedge

Propulsionsystemtankandbilletblank. Propulsionsystemcapandbilletblank

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PropulsionSystemDetails

TankandcapinterfacesealedwithEDPMOring

Stainless

stud

with

laser

drilled

hole

provides

fluid

path

to

thrustervalve

StudusesEDPMoringtoseal

Underside

of

cap

with

o

ring

installed Stainless

stud

with

EDPM

o

ring Underside

of

cap

with

stud

installed

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PropulsionSystemDetails

Thrustervalvemountstostudandseatsagainst

cap

boss

(middle) Schradervalvemountedtocapusedforfill/drain

(right)

Capshownwithvalvemountingstud Valveassembledtocap Schradervalveassembledtocap

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PropulsionSystemdetails

Thrustermadefromstainlesssteel Prototype(heavy)thrustershown(left)

Catalystmadefromplatinummeshandplatinum/iridiumwirescreens Screensarestackedandheldbystainlessfasteners

Numberofscreenscanbevariedduringtesting

Thrusterassembly PlatinumCatalyst

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PropulsionSystemDetails

Drymassfractionforpropulsionsystemunit=0.45

Expected

delta

V

up

to

400m/s

Propulsionsystemassembly.

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TestPlan

TankBurstTest InvestigateFailureMechanism

PPODIntegration Verifysmoothoperation

HotFireTest

Catalyst

Function

and

integrity Minimuminletpressureforthruster

operation

Thrustmeasurements

MicroPropulsionModuleandPPODtestfit

ValveCyclingtestunderpressurization

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FutureWork

PropellantManagementDevice

WorkinProgress

ControlandNavigationSystem

Qualification

Testing

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AnyQuestions?

ChrisBiddy174SuburbanRdSuite120

San

Luis

Obispo

CA

93401(805)5498200

chris@stellarexploration.com