Missile Works RRC3 User manual

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
RRC3–RocketRecoveryController3
UserManual

Revision1.60
Missile Works Corporation
PO Box 1725, Lyons CO 80540
www.missileworks.com

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Introduction
Overview

TheRocketRecoveryController3(RRC3)isabarometricdual‐deployaltimeter,withthefeaturesofhigh‐endunits,atthe
costofthosewithamoremodestfeatureset.Inadditiontobasicdual‐deploycapability,theRRC3isamulti‐flightrecording
unit,allowingyoutoflyallday,withouttheneedtostopanddownloaddatainbetweenflights.
Two‐stage(ordual)deploymentispreferabletosingleparachuteorstreamerrecoverysystemsforhigh‐powerrocketry.
Recoveryoflarge,heavyrocketswithasmallparachuteorstreameralonedoesnotsupplyenoughdragtosafelyrecover
therocketwithoutdamage.Anadequatelysizedparachutedeployedatahighaltitudemaycausetherockettodriftoutof
thelauncharea,makingrecoverydifficultifnotimpossible.
Twostage(ordual)deploymentrecoverysystemseitherseparatetherocketairframeintotwosectionsorejectasmall
drogueparachuteorstreameratapogee,allowingtherockettodescendatarapidyetcontrolledrate.Whentherocket
descendstoapredeterminedaltitudeaboveitsinitiallaunchelevation,itthendeploysthemainparachute,allowingthe
rockettomakeasafelanding.
PrimaryFeatures

●DrogueandMainoutputs
●ConfigurableDeploymentoperations
●ConfigurableMainandArmingaltitudes
●User‐selectablebeepfrequency
●Configurablethird"Aux"output
●15flightmemory@~28minutesperflight
●Livedatastreamingandtelemetrycapability
Specifications
Microcontroller16MHz16‐bitMSP430SeriesmCU
OnboardFlightmemory  8MbitSSTFlashMemory
Pressure/Temperaturesensor MSIMS5607Pressuresensorwith24bitΔΣADC
OperationalRanges  StandardUnit(40K/100KMSL)/XtremeUnit(100KMSL)
ArmingModeBarometric
Minimumaltitudeforarming 100feet(adjustable)
Battery3.5voltsto10volts
TestCurrent   17µato50µa(batterydependent)
FiringCurrent3ampsfor1second(Drogue/Main)
Dimensions23.5mmx99.5mm(0.925”x3.917”)
HandlingPrecautions
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AlwayshandletheRRC3inastatic‐free,groundedenvironment
Nevertouch/handletheRRC3whenitisarmedandconnectedtolivepyrotechniccharges
AlwaysallowtheRRC3toadjusttoambienttemperatureconditionspriortoarmingandflying
AlwaysprepareyourrocketandrecoverysystemcomponentswiththeRRC3poweredoff
NevercycletheRRC3powerswitchoff,thenimmediatelybackon(allowatleast10seconds).

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RRC3SystemOptions
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ComputerUSBinterfaceboard,forconfigurationanddatadownloadviamDACSPCsoftware
BluetoothinterfaceboardforSmartphoneconfigurationanddatadownload
LCDinterfaceterminalforfieldconfigurationofunitandfieldreviewofflightdata
ComboGPS/Telemetryboardforlivedownlinkoflocation/datastream
PerfectFliteDT2/DT3interfaceadapterfortheconfiguration/downloadfromRRC3
WiringharnessesforcustominterfaceofCommandAuxiliaryOutput
AuxiliaryPyroExpansionboard,providingadditionaloutputchannelsandtiming
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DefaultBaseSettings
ArmingAltitude300’AGL
MainDeploymentAltitude  500’AGL
DeploymentModeDrogue@Apogee/Main@AGLaltitude
AudioOptionsContinuityBeep
UnitsFeet/Feetpersecond
LowVoltageLockout  Disabled
PiezoTone1.04KHz
DrogueDelay1second(UsedinBackupModeonly)
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NOTE:YoucanresetthesettingsoftheRRC3backtothesedefaultsusingthefollowingprocedure:
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‐PushandHoldtheprogrammingpushbutton.
‐ApplypowertotheRRC3whilethepushbuttonispressed(theLEDwillflicker).
‐Continueholdingdownthepushbuttonforapproximately5seconds.
‐Releasethepushbuttonwhenitbeeps(refertoPOSTcodesintheOperationalModessection).
‐ShuttheRRC3off.

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Installation
AltimeterMounting
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TheRRC3doesnothavean“up”orientation,andcanbemountedinanyconvenientorientation.Itisimportanttomount
thealtimetersecurely,preventingitfromsufferingdamageduringflight.
Whenplanningthelayoutofyouraltimeterbay,inadditiontomountingtheRRC3,besuretoprovidesecuremountingfor
thebattery.Anunsecuredbatterycanbreakfreeduringrecoveryevents,resultingindamagetothealtimeter.
4/40screwhardwareisrecommendedtomounttheRRC3ontothealtimeterbay“sled”oftherocket.Nylonstandoffsor
insulatedwashersarealsorequiredtoprovideclearanceforthebarometricsensorlocatedonthebottomsideofthecircuit
board.
ThealtimeterbaysectionusedfortheRRC3mustbeasealedchamberwithastaticpressureports(seethenextsectionfor
portsizing).Thesealingofthechamberisnecessaryforseveralreasons:
Isolatestheelectronicsfromtheejection‐chargeheat,residue,andover‐pressure
Isolatestheelectronicsfromtheaerodynamicpressureandvacuumduringflight
Providesuniformstaticpressureequilibriumtoambientpressureduringflight
IMPORTANT:Inadequatesealingoftheelectronicsbayorexposureoftheelectronicstoejectionchargeheat,BPresidue,
orpressurewillcausetheRRC3tomalfunction.
IMPORTANT:Blackpowderresidueisextremelycorrosivetothecircuitboardanditscomponents.Alwayscleanoffany
inadvertentresidueimmediatelytoavoidlong‐termdamagetotheunit.
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StaticPressurePorts
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Barometricaltimetersrequireequalizationoftheairpressureinsidethealtimeterbayandtheairpressureoutsidethe
rocket.Toprovidethis,oneormorestaticpressureportsarerequired.Whileoneportcanbeused,toreducespurious
readingsduetowindacrossasingleport,multipleequallyspacedportsisrecommended.
Staticportsshouldbelocatedwheretheyarenotaffectedbyanythingwhichcancauseturbulenceintheairflowoverthe
port.Thisincludesrailbuttons,screwheads,noseconesandtransitions–thefartherthestaticport(s)canbelocatedfrom
suchitems,thebetter.

5
Thesizingofstaticport(s)requiresthatyoufirstcalculatethevolumeoftheelectronicsbayasfollows:
Volume=BayRadius(inches)xBayRadius(inches)xBayLength(inches)x3.14
Next,usetheappropriatesingleportformulatocalculatethesizeofasingleport:
Forvolumes<100SinglePortDiameter(inches)=Volume/400
OR
Forvolumes>=100SinglePortDiameter=2xSQRT(Volume/6397.71)
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Ifyouplantousemultipleports(recommended),determinehowmanyportstouse(aminimumof3isrecommended),
thencalculatethesizeofeachportusingthesemulti‐portformulas:

SinglePortArea=(SingleVentDiameter/2)x(SingleVentDiameter/2)x3.14
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MultiPortDiameter=2xSQRT((SingleVentArea/#ofholes)/3.14)
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PowerandWiringConsiderations
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TheRRC3isdesignedtobeoperatedwithastandard9‐voltalkalinebattery.Standard9Valkalinesareanoptimalchoice,
providinganinexpensiveandwidelyavailablebatterytypewithsecuresnapconnectors.Alwayspurchaseanduse
premiumalkalinebatteries.
Otherbatterytypescanbeused,includingNiCd,NiMH,LiPo,orotherbatterychemistries.Yourbatterychoicemustsource
andmaintainanabsoluteminimumof3.5volts,andalsobelimitedtoamaximumof10volts.
Itshouldbenotedthat9Valkalinebatteriescansourceamaximumdischargecurrentofabout3ampsintoashort.The
Drogue,Main,andAuxoutputsoftheRRC3areratedfor3Aservice.Whenusingotherbatterieschemistriesthatcan
sourcehigherdischargecurrents,usersshouldensuretheoutputconnectionstotheDrogue,Main,andAuxarenot
shorted,andtheconnectedelectronicmatchloadsdonotexceed3Atoavoiddamagingtheunit.

Thebrownoutcapacitorisoptimizedtopreventanover‐currentbrownoutconditionwhenoperatingtheRRC3witha9volt
battery.Lowerbatteryvoltagesreducethetotalbrownouttimecapabilityofthecapacitor.Ifyoudochoosetousealower
voltagebatterythan9V,ensureyourbatteryhasadequatevoltage/powerreservetopreventabrownoutconditionduring
flightduetoavoltagedip,andthatyoupayextraattentiontotheloadsrequiredbyyoure‐matches.
NominalpowerconsumptionfortheRRC3isapproximately6ma.Whenbeepingorflashinghowever,powerconsumption
canjumpupto≈35ma.DuringPre‐launchonthepad,andPostFlightafterrecovery,thealtimeterwillbeepandflashthe
LED.Duringflightoperations,theLEDwillilluminatewhenthevelocitydiscriminatorlockoutconditionsareactive.
IMPORTANT:Alwaysuseabatterysystemof10VoltsorlesstoavoiddamagingtheRRC3
.
IMPORTANT:Alwaysload‐testyourbatterypriortoflighttoensureadequatepowerreserveforreliableoperationand
ignitionoftheejectioncharges.Inadequatesizingofanexternalbatterysystemorhigh‐currentdemandsonthebattery
systemduringeventinitiationmayleadtopowerandprocessorbrown‐outconditions,resultinginrecoveryfailure.

6
Inaddition,itisimportanttopayattentiontobatterypolarity–thepositiveterminalonthebatterymustbeconnectedto
thepositiveterminal(markedwitha+sign)onthealtimeter.Connectingthebatterybackwardswillnotdamagetheunit,
howeverthealtimeterwon’toperate.
Stranded20‐22AWGwireisrecommendedforthebatteryandpowerswitchterminals.

PowerSwitchConsiderations
Inadditiontoprovidingapowersource,apowerswitchshouldbeconnectedtotheswitchterminals(nexttothepower
terminals)onthealtimeter.Theswitchusedcanbeassimpleasapairofwireswhicharetwistedtogetherpriortoflight
(i.e.“twistandtape”),orascomplexasamagneticallyactivatedsolid‐stateswitch.
Switcheswhichprovidedpositive,bounce‐freecontact,suchastwistedwires,highqualityrotaryorleverswitches,push
on/off,andscrewswitches,arerecommendedfortheirsimplicityandreliability.
Ifyoudousethe“twistandtape”method,pleaseusethefollowingguidelines:
 DoNotpokethewiresbackintotheairframeaftermakingaconnection.Whenthewiresarepokedbackintothe
airframe,thiscreatesasafetyissueshouldtherocketneedtobedisarmedandremovedfromthepadforanyreason,
asitisdifficult,ifnotimpossible,tofishthewiresbackoutofthehole.

 Maintainpositivecontactofthestrippedwireendswhiletwistingthemtogethertoavoidpowerbobbleswhichcan
leadtobrownoutsorotherundesiredresults,includingpotentialoutputeventactivationsduetopotentialundefined
statesofoperation.

 Itisbesttotapetheleads,aftertwistingthem,thentapethemtotheairframe,orpoketheendintoanotherholeon
theairframe,leavingalengthofwireexposedandaccessibleontheoutsideoftheairframe.
Ifyourusingan“active”switchthatsourcespowerandispolaritydependent,the(+)batterypowerswitchterminalis
locatedadjacenttothebatterynegativeterminal.Theswitched(+)powerterminalistheotherswitchterminal.

DrogueandMainEjectionChargeConnections
TheRRC3isdesignedtobeusedwithlowcurrentelectricmatches(Daveyfire,Oxral,MTEK,JTEK),orlowcurrentmotor
igniters(QuestQ2G2).
It’salsoextremelyimportantthatyoupayattentionandvalidatethatyouconnectyourdrogueejectionchargetothe
drogueterminalsandthemainejectionchargetothemainterminals.Theseterminalsareclearlymarkedontheboard
withpositiveandnegativedesignations.

TheRRC3employstheuseofan“OpenDrainMosFET”devicetoactivatetheejectioncharges.Thebatteryvoltageis
alwayspresentonthe(+)terminalwhilepowerisappliedtotheRRC3,andthe(‐)terminalisahighresistanceconnection
thatpreventsanycurrentflowuntiltheMosFETisgatedonattheappropriateeventtime.

7
IMPORTANT:NEVERattachliveejectionchargeswiththealtimeterpoweredON.Alwaysconnectliveejectioncharges
withthealtimeterpoweredOFF.
Alwayspre‐measureyourdeploymentchargematchesorignitersforanominalresistanceandverifytheyarenotshorted.
Anominalresistanceforalowcurrentdeviceshouldbeintherangeof1to2ohms.

AtthePad

Atthelaunchpad,beginbyplacingyourrocketonthepad/rail,andraisingtherockettothevertical(launch)position.Do
notinstalltheigniteratthistime.
Beforeyouarmthealtimeter,havebystandersremovethemselvestoasafedistancewheretheywillnotbeinjured,should
theejectionchargesfireprematurely.
Turnonthearmingswitchforthealtimeter,andlistenforthestartupsequence.Thealtimeterstartupsequenceisas
follows:
1. 5secondlongbeep(initmode)
2. 10secondbarohistoryinittime(silence)
3. Settingsbeep(whenenabled)orPOSTfaultcodebeep(ifafault,seePOSTfaultcodes)
4. 10secondlaunchcommittesttime(silence)
5. LaunchDetectmode(continuitybeeps)
a. Alongbeepindicatesnocontinuityonanyeventterminal.
b. Oneshortbeepindicatescontinuityononlythedrogueterminal.
c. Twoshortbeepsindicatecontinuityononlythemainterminal.
d. Threeshortbeepsindicatecontinuityonthemainanddrogueterminals.
Assumingthealtimeterbeepsouttheexpectedcontinuitystatus,youraltimeterisreadyforlaunch.Atthispoint,you
shouldinstalltheigniter,connecttheigniterleads,andleavethearea.
Shouldtherebeaneedtoremovetherocketfromthepad,orotherwisechangeitsposition,beginbydisconnectingand
removingtheigniter.Then,turnoffthearmingswitchforthealtimeter,andwaitaminimumof10secondsafterthe
altimeterstopsbeepingbeforemovingtherocket.

AnalyzingYourFlight

Afteryourflight,thealtimeterwillbeep/flashoutyourpeakaltitudeusinga"perdigit"method.Forexample,let'ssayyour
rocketflewtoapeakaltitudeof2,340feet.You'dhearthefollowingbeepsequence:
beep‐beep(2),shortpause
beep‐beep‐beep(3),shortpause
beep‐beep‐beep‐beep(4),shortpause
beeeeeeeeeeeeeeeep(0),shortpause

8
Shortlowtonebeep(endofaudiovaluereport)
Longpause(beepingwillrepeat)
Thealtimeterwillcontinuetobeepasdescribeduntilpoweredoff.Thereareadditionalflightdataitemsyoucanenableto
beepaftereachflight(seethe"AudioOptions"settingintheAdvancedOperationsection).

OperatingTipsforSuccess
Alwayspre‐testyouraltimeterasCOMPLETELYaspossiblepriortoeveryflight.Thisincludesatestoftheinputs,
outputs,andbarosystem.ThesetestscanbeperformedusingthediagnosticscapabilityoftheRRC3(seetheAdvanced
Operationsection).

Alwayspre‐testyourbatteriesbeforeeachflightandensuretheyhaveadequatepowercapacityfortheanticipated
worstcaseflightprofile,includingunplanned“on‐the‐pad”waitingtime.

Alwayspre‐measureyourdeploymentchargeinitiators.Measurethemforanominalresistanceandverifytheyarenot
shorted.

Properport‐sizingcreatesidealequilibriumrates.Ensurethatyourportingiscompliantwiththerecommendedsizing.
Improperlysizedportingorotherleaksintheelectronicsbaycancreateparasiticpressureeffects,impacting
equilibriumratesandreliablerecovery.

AdvancedFeaturesandOperation
TheRRC3providesanumberofadvancedfeaturesandoperationswhilestillmaintainingandprovidingthebasicsofsimple
andreliabledualeventrecoveryandpeakaltitudedetermination.Theseadvancedfeaturesareeasilyaccessible,butdo
notinterfereorgetinthewayofthebasicfunctionsthattheRRC3provides.

DualBatteryWiring
TheRRC3isdesignedtoflyusing9Valkalinebatteriesintandemwithlowcurrentematchesforthedrogueandmain
deploymentcharges.Shouldyourapplicationrequirehighercurrentforoutputevents,oryouroperatingatlowerbattery
voltagesyoumightconsiderusingadualbatterywiringsetup.ThismethodisolatestheRRC3LogicBatterypowerfromthe
Drogue/MainDeploymentchargepower,thuseliminatinganypotentialvoltagebrown‐outscenariosduringevent
activation.Thelogicbatterymustcomplywiththe3.5VDCto10VDCratingasmentionedinthespecs;howeveryourpyro
batterymaybeanyvoltageuptoanabsolutemaximumof30VDC.
ItisalsorecommendedwhenusingthisdualbatteryoperationtofirstactivatetheRRC3LogicSwitch,andafterverification
ofasuccessfulboot,thenactivatethePyroSwitch.


9
Whenusingdualbatteries,usethefollowingwiringdiagramasaguide.


RRC3OperationalModes
TheRRC3‐minihasseveraldistinctmodesthroughoutthecourseofitsoperationduringflightandrecovery.Thesemodes
ofoperationareidentifiedbythefunctionofthepiezoandtheLED,andthespecificphaseofflight.

PowerUpandPre‐LaunchModes

Power‐upInitializationMode
Whenpowerisfirstappliedtotheunit,itwillprovideacontinuous5‐secondbeeptoindicateithasbeenswitchedon.
Duringthis5‐secondtimeperiod,theRRC3islookingforatapofthe“Program”button(invokingtheDIPSwitchOperations
Mode)TheLEDwillremainoncontinuouslyduringthePower‐upInitializationMode.

BaroHistoryInitializationMode
AfterthePower‐upInitializationmode,theunitgoesthrougha10‐secondbaroinitializationstart‐updelay.TheLEDwill
flashonandoffevery2secondswhileinthismode.Thisdelayperiodallowsbarometricstabilizationandestablishesan
initialbarometrichistory.TheRRC3alsolooksfora“HostConnection”messagefromahostPCcomputer(attemptingto
connectinHostorSimulationModes).TheseoperationsarecoveredinsubsequentmDACSUserManual.

POSTMode(PowerOnSelfTest)
Onceabarometrichistoryisestablished,theRRC3performsseveralPOSTcheckstovalidatetheintegrityofallsensorsand
tocheckthecurrentambientenvironmentalconditions(pressureandtemperature).

Ifthereareanydetectedsystemwarningsorfaults,orconditionsthatfalloutsideofspecifiedranges,thealtimeterentersa
POSTFaultCodeloop,whereitrepeatedlyreportsthespecificfaultthatitencountered.TheRRC3isunabletoflyuntilthe
faultorwarningiscorrected.

POSTFaultCodesareprecededbyaverydistinctwarningtone(7veryquicklowbeeps),followedbythebeepingand
flashingofthespecificfaultcode.

10
ThefollowinglistsallPOSTFaultCodeconditions:

POSTFaultCodeDescription
1 UserinvokedSettingsDefaulttoFactorySettingswarning
2 LCDTerminalFault/LCDisattachedandaDIPSwitchisON
3 BarometricsensorFault/Nocommunicationreply
4 BarometricsensorFault/PromCRCMismatch
5 BarometricpressureFault/Pressure<10mbaror>1200mbar
6 TemperatureFault/Temperature<‐40deg.Cor>85deg.C
7 LowBatteryLockoutFault/Battery<LowVoltageLockoutLevel
8 AmbientBarometricFault/UnstableconditionsduringLaunchCommitTest

POSTCodeNotes:
‐Code1isbeeped/flashedwhenevertheuserperformsaFactoryDefaultOperation.
‐Code2isbeepedflashedifyouconnecttheLCDTerminalwithaDIPSwitchintheONposition.
‐Codes3thru6indicateahardwarefault.ContactMissileWorksforwarrantyorservicedetails.
‐Code7indicatesthebatteryisat/belowthespecifiedLowVoltageLockout.Replaceyourbattery.
‐Code8indicatesthatambientbaroconditionsareunstableforthecurrentlyprogrammedArmingAltitude.Eitherraise
theArmingAltitudesetting,orconsiderflyinginmorestableconditions.

AudioOptionsReportMode
IfyouhaveenabledanyofthePre‐LaunchAudiooptionsoftheRRC3,theywillbebeeped/flashedatthisstageof
operations.Theseaudiooptionsincludebeeping/flashingofbatteryvoltageandDeploymentmodes.(seethefollowing
“BaseSettings”sectionifthemanualformoredetails).

LaunchCommitTest
TheLaunchCommitTestisa10secondtestoperationthatisa“trialrun”oftheLaunchDetectMode,applyingthe
currentlyprogrammedArmingAltitudeagainstambientconditions.ShouldambientconditionsbesuchthataLaunch
Detectconditionisvalidduringthistestperiod,theRRC3willinvokeaPOSTCode8condition(seeabove).Duringthe
LaunchCommitTest,theLEDflashesonandoffata1secondrate.

LaunchDetectMode
Whenallpreviousmodesarecomplete,theunittransitionsintoLaunchDetectMode.ThepiezoandtheLEDwill
beep/flashtoindicatethecontinuitystatusofthedrogueandmainoutputterminalsevery5secondsasfollows:
LongBeep/FlashNocontinuityonDrogueorMain
1ShortBeep ContinuityonDrogueonly
2ShortBeeps ContinuityonMainonly
3ShortBeeps ContinuityonDrogueandMain

TheRRC3monitorsthebarometricsensorforachangeinaltitudeasspecifiedbythecurrentArmingAltitudesettingto
determinethelaunchoftherocket.AssoonthethecurrentaltitudeexceedstheArmingAltitude,theRRC3isactivated
andLaunchDetectisdeclared.
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