This document summarizes testing of the Silver Board V1 solar panel design for the ANDESITE CubeSat mission. Individual strings of solar cells on the board were tested and found to be producing open circuit voltages between 18.9-20.1V and currents around 0.02A. Total power production of the 48-cell panel was calculated to be 2.3702W. While the positive terminal connection was functioning properly, the negative terminal connection was not producing a circuit. Further modeling will account for varying solar incidence angles in orbit. The solar cells were found to be operating within the expected 27% efficiency range required to meet ANDESITE's power requirements.

1. This document is part of the ANDESITE team documentation, and its purpose is to independently serve as a
comprehensive guide to understanding, operating and rebuilding the subsystem described within. This document is the
authoritative resource for this subsystemand supersedes all other previously written documentation including presentation
slides, previously written Design Documents, and individually recorded notebook entries. This document is part of the
BUSAT NS-7 System Concept Review (SCR) documentation suite submitted to the University Nanosat Program (UNP)
March 8th, 2013.
ANDESITE (NANOSAT-8) PROGRAM
Solar Panel Test Results (Silver Board)
Document #1
Boston University
8 St Mary’s St
Boston, MA 02148

2. CHANGE LOG
Revision Date Submitted Authors Description Notes
v1 09.15.2014 MS RVM
Documentation
Testingisnear
completionpoint
Table 1: Change Log
RELEASE APPROVAL
Prepared
By:
Mike Schuller,ANDESITE Solar Engineer, Boston University Date
Someone, Job, Boston University Date
Someone, Job, School Name Date
Someone, Job, School Name Date
Someone, Job, School Name Date
Someone, Job, School Name Date
Approved
By:
Professor Ted Fritz, PI,Boston University Date
Steven Yee, Project Manager, Boston University Date
Joshua Mendez, Project Engineer, Georgia Tech Date
Subsystem Mentor , School Name Date

3. 1.1 List of Acronyms
Acronym Definition
ADC Analogto Digital Converter
ADK AndroidDevelopmentKit
AMR AnisotropicMagnetoResistive
ANDESITE Ad-hocNetworkDemonstrationforExtendedSatellite Inquiriesandother
Team Endeavors
BU BostonUniversity
BUSAT BostonUniversityStudentSatellite forApplicationsandTraining
C&DH Commandand Data Handling
Co-I Co-Principal Investigator
COTS Commercial Off-The-Shelf
CSP (BostonUniversity) CenterforSpace Physics
DOF Degree-of-Freedom
Ga Tech GeorgiaInstitute of Technology
GENSO Global Educational NetworkforSatelliteOperations
I2C Inter-IntegratedCircuit
IMU Inertial MeasurementUnit
NS-7 Nanosat-7
PAVE-PAWS PrecisionAcquisitionVehicle EntryPhasedArrayWarningSystem
PCB PrintedCircuitBoard
PI Principal Investigator
RVM RequirementsVerificationMatrix
SEL Single-EventLatchup
SPI Serial Peripheral Interface Bust
TASC TriangularAdvancedSolarCell
TIME TwinImagingof the Moving Electrontrappingboundary
TRL TechnologyReadinessLevel
UART Universal Asynchronous Receiver/Transmitter
UNP UniversityNanosatProgram
USB Universal Serial Bus
WSN WirelessSensorNetwork

4. (THIS PAGE INTENTIONALLY LEFT BLANK.)

5. 1. RVM Requirements
EPS Electrical PowerSubsystem
EPS-8 The solar cell mustproduce sufficientpowerforthe durationof mission.
EPS-
8.1
The solar cellswill operateatefficiency withinthe range indicatedby
manufacturer.
EPS-9 The componentsof the EPS won'tconsume more than the powergenerated.
It isexpectedthatthe solarpanelswill provide chargingtothe onboardbatteriesof the
mule andwirelesssensornodesinorderforthe batteryto powerthe componentsused.In
orderfor thisto occur, requirementshave been placedonthe solarpanelsinordertoensure
operationsof ANDESITEcan be carriedon uninterruptedforthe twoweekscience missionit
will endure.Those requirementsare asfollows:the solarcells(TASC)usedonANDESITEmust
operate withinthe indicatedefficiencyrange designatedbythe manufacturer,the solarpanels
mustconstantlycharge the batteriesata rate suitable tolastthe twoweekmissionlife,and
the componentsonboardmustnotconsume more powerina single orbitthanwhatthe solar
panelscangenerate inorderto guarantee batterylife.
Testinganddata analysiswere completedasacheck that these requirementswere
beingmet.A copy of the firstsolar panel circuitboarddesignforthe wirelesssensornode was
manufacturedtoact as a testingboard.The cellsusedwere donatedfromapreviousuniversity
satellite projectinordertoefficientlysave resourcesforthe final design.Thesecellsare TASC
and producedbySensorMetrix,the same manufacturerandcellsthatwill be usedforthe final
design.
2. Silver Board V1 Design
1.1 Update from Brass board
The redesignedsolarpanel circuitboardforthe sensornodeswasdesignedwiththe
powerbudgetof the sensornodesinmindandanchoredtowardproductionof sufficientpower
to sustainmissionlife forANDESITE.The resizingof the sensornode housingtoaccommodate
the 10Ah single cell LiPobatterychosenforthe missionprovidedmore thananacceptable
amountof surface areafor solarpanels.The increasedsurface areaincreasedthe number of
solarcellsfrom20 (Bronze board) to 48 that couldbe assembledonthe outside of the housing.
It was determinedthatprovidingattitude control onthe sensornodeswouldconsume
more powerthan couldbe reproducedbysolarpowertoremainoperational foratwo week
missionlife.Due tothiscondition,spinstabilizationof the sensornodeswill nolongerbe
incorporatedandthe nodeswill tumblefreelyafterejection. The lackof control presentedan
issue withsolarpowergeneration.Toaccountfor randomtumblinginspace,the conclusionwas

6. to put equivalentsolarpanelsonthe topand bottomof the housing.Modelingof thisapproach
provedthatthe power(Wh) generated inafull orbitof a tumblingnode withpanelsonboth
sidesequaledpowergenerationof acontrolled node withonlyone solarpanel.Fromthis,the
designwasapprovedfordevelopment.
1.2 Silver Board V1 Layout
The silverboarddesignmockedthe brass boardalmostentirely,the onlysubstantial
difference beingthe numberof cellsonthe boardincreasingfrom20 to 48 TASCs. The size of
the board is10.5cm x 17.5cm. The boardcontainssix stringsof cellsinparallel,eachstring
connecting8 solarcellsinseries.Eachcell iscontactedto the board withsevensurface mount
pads.A single padwouldsuffice,butwitha50g environmentandthe fragilityof TASCsseven
pads were usedtolowerthe chance of defectsoccurring.The sevenpadsundereachcell are
linkedinserieswitha.254mm trace routedintothe board.The same size trace runs fromthe
seventhpadof eachcell ina stringto an eighthsurface mountpadplacednearthe positive
contact of the nextcell inthe string.Atthe endof eachstring of cells a 1mm trace inthe board
runs to a junctionpointwhere all stringsconvergetoone.The trace size wasincreasedfrom
.254mm to 1mm to account forthe increase incurrentproducedbythe convergence.The single
trace producedbythe junctionof stringsisroutedto a thru hole neara corner of the board,
designedtobe interfacedtothe EPSfromthe bottomof the board. Thisthru hole actsthe
positive terminal forcurrentdraw to the EPS.
The firstcell of eachstringneededtobe connected ina similarfashionasthe lastcells
of eachstring,butto avoidexcessiveroutingandretainsimplicity,adifferentmethodwas
conducted.Insteadof runninga1mm trace junctionlike the otherendsof strings,the seven
pads of everyfirstcell wasexposedtothe topcopperlayerof the board.The top copperlayer
acts as the junctionwiringthe negative endof the stringstogether.A secondthruhole isalso
exposedtothe topcopperlayerand islocatednexttothe positive thruhole forEPSwiring
convenience.The secondthruhole actsas the negative terminalforthe solarpanel.Eachthru
hole is1mm indiametertofitthe junctiontrace as well assecurelyandefficientlysolderwires
fromthe solarpanel tothe EPSinside the housing.
Four thruholes,eachwith 2mm diameters,are placednearthe cornersof the board.
These thruholesare not exposedtoanylayersof the board nor have trace runningto or from
them.These holessimplyactas mountingholesfor6-32 screwsto secure the solarpanel board
to the outside of the sensornode housing. The twoholesnearthe backof the sensornode
(closesttothe mule attachment) are 8mm upfrom the back edge and3mm in fromthe sides.
The two holesnearthe frontof the sensornode are 13.5mm fromthe front edge and3mm in
fromthe sides.

7. 3. Silver Board V1
3.1 Testing Procedure
The solar panel wasassembledinasolderinglabbymembersof ANDESITE.The method
takenwas equivalenttostandardsolderingtechniquesforsurface mountparts.The procedure
includedcoatingall surface mountpadswithsolderfluxtocleanthe padsof any impuritiesthat
may affectelectrical connection.Since the padsare locatedunderneaththe TASCs,usinga
soldergunto assemble the cellswouldnotbe feasible.Instead,solderpaste waslaidoneach
surface mountpad and the cellswere placedinthe correctgeometricorientationontopof the
solderpaste.
Once all cellswere carefullyplaced,the boardwastakentoa reflow oventosolidifythe
connectionbetweenthe cellsandthe board.A pre-designatedheatprofile wasselectedfrom
software torun the reflowprocess.Afterwards,the cellswere cleanedandcheckedfordefects.
Once it wasdeterminedall cellswere cleanandclearof anydefects,the assemblyprocesswas
continued.Lead-free solderwire andsolderinggunwere usedtocreate the electrical
connectionbetweenthe remainingsurface mountpadsandthe positive(top) sideof the cells.
The solar panel wascleanedagainasa precautionarymeasure andthenwasreadyfortesting.
The fullyassembledsolarpanel wastakentothe roof of a laboratorybuildingwitha
hand-heldmultimeter,electrical wire anda100ohm resistorforperformance testing.Testing
occurredduringa clearskyday around12:30pm to mimicorbital environmentasideallyas
possible.Itwastakenintoconsiderationthatlowertestresultscouldbe expecteddue tothe
conditions.
3.2 MeasurementMethods& Data
Poweroutputof TASC ismeasuredbydeterminationof the Open-CircuitVoltageand
Short-CircuitCurrentproducedbythe cell ata giveninstantintime.UsingOhm’sLaw allowsthe
poweroutputinwattsof each panel tobe estimatedinwatts(W). Computingthisvalue is
desirable foranalyzingthe efficiencyinwhichthe cellsoperateanddeterminingwhetherornot
theyare acceptable forapplicationonANDESITEtomeet the designrequirementsindicated.
The testingprocedure implementedonthe TASCsoughtto make thisanalysis.
An opencircuitvoltage testwasrunby attachingthe positive andnegative leadsof the
multimetertothe correspondingthru-hole pinsonthe solarpanel.The solarpanel wasoriented
to be as incidentwiththe solarilluminationashumanlypossibleandmeasurementwastaken.
Followingthat,opencircuitvoltagewasalsorecordedforeachstringof cellsbyattachingthe
negative leadof the multimetertothe bottomof the firstcell ineachstringand attachingthe
positive leadof the multimetertothe positive contactof the lastcell ineachstring.
Measurementswere takenforeachstringandrecorded.

8. Afterthe opencircuit voltage testswere complete,acurrenttestwasimplementedfor
each stringandthe whole solarpanel.The wholesolarpanel wastestedfirstbyattachingone
endof the 100ohm resistortothe positive thru-hole pinonthe solarpanel andthe otherendto
the positive leadof the multimeter.The negativeleadof the multimeterwasthenconnectedto
the negative thru-hole pintocomplete the circuit.Measurementwastakenandrecorded.The
same setup procedure wasdone foreach stringof cellsexceptthe endof the resistor
connectedtothe thru-hole pinonthe boardwas movedtothe positive contactof the lastcell in
each stringandthe negative leadof the multimetertothe bottomof the firstcell ineach string.
Table 1: Current and Voltage readings
(-) Leadconnection (+) Leadconnection OC Voltage (V) CC Voltage (V) *SC Currant (A)
Ground Pin Positive Pin 0 0 0
String1 Beginning String1 End 18.9 16.9 .0200
String2 Beginning String2 End 18.9 16.9 .0200
String3 Beginning String 3 End 18.9 16.9 .0200
String 4 Beginning String 4 End 20.1 18.0 .0210
String 5 Beginning String 5 End 20.1 18.0 .0210
String 6 Beginning String 6 End 19.6 17.6 .0200
String 1 Beginning Positive Pin 18.9 16.9 .0200
String 2 Beginning Positive Pin 18.9 16.9 .0200
String 3 Beginning Positive Pin 18.9 16.9 .0200
String 4 Beginning Positive Pin 20.1 18.0 .0210
String 5 Beginning Positive Pin 20.1 18.0 .0210
String 6 Beginning Positive Pin 19.6 17.6 .0200
Ground Pin String 1 End 0 0 0
Ground Pin String 2 End 0 0 0
Ground Pin String 3 End 0 0 0
Ground Pin String 4 End 0 0 0
Ground Pin String 5 End 0 0 0
Ground Pin String 6 End 0 0 0
* SC Currentwascalculatedbymeasuringthe dropinvoltage fromOpen-Circuit(OC) toClosed-
Circuit(CC) across a 100 ohmresistorload andusingOhm’sLaw to determine the currentbased
on the voltage dissipatedacrossthe resistor.
Ohm’sLaw V = IR
3.3 Data Analysis

9. The issue arose that none of the stringsof the solarpanel were displayingcurrentvalues
on the multimeter.Itwasdeterminedthatthe multimeter’scapabilitycouldnotreadcurrent
valuesaslowas the cell stringswouldproduce evenatmax powerproduction.Insteadof
readingcurrentvalues,voltage valueswerereadandrecorded whenaloadwas appliedtothe
circuit.It wasjustifiedthatthiscouldbe done because withthe voltagevalue readbythe
multimeter,the voltage dropacrossthe load of knownresistance couldbe determinedby
subtractingthe opencircuitvoltage recorderbefore andsubtractingthe voltage valueread
duringthe currenttest.The resultingdifference wastakenasthe voltage dropacrossthe load
and Ohm’sLaw wasusedto determine the currentthroughthe resistor,whichwouldequateto
the current producedbythe solarpanel.
Anotherissue thatoccurredduringtestingwaswhenthe whole solar panel wasbeing
analyzedasa whole.Bothtestsresultedina0V readout, implyingthatthe boardwasnot acting
as a complete circuit.The individual cellstringtestswere runtodetermineif there were defects
inthe stringassembly.Fortunately,all stringsproducedopencircuitvoltage andproduced
current.From these testresults,boththruhole were analyzedindividuallywiththe cell strings.
Withthe positive leadof the multimeterconnectedtothe positivethruhole andthe negative
leadof the multimeterconnectedtothe beginningof acell stringa voltage equivalenttothatof
the stringitself wasmeasured.Thiswasrepeatedforeachstringof the boardand the same
resultoccurredfor eachtrial.These testsindicatedthe positivethruhole isfunctioningproperly
and receivingavoltage andcurrentfromthe solar panel.However,whenthe groundthruhole
was connectedtothe negative leadof the multimeterandthe positive contactof a string
connectedtothe otherlead,again 0V readoutoccurred.Thiswas repeatedforeachstringand
indeedthe same resultoccurredacrossthe board.
In orderto analyze the powerproducedbythe solarpanel asa whole, the powerof the
individualstringswere calculated usingOhm’sLaw andsummedtoform total power
production.
Table 2: Panel Power Production
Cell String Power Output (W)**
1 0.378
2 0.378
3 0.378
4 0.4221
5 0.4221
6 0.392
***Total 2.3702 W
** PoweroutputwasanalyzedusingOhm’sLaw (P=VI),where V wasthe opencircuitvoltage readacross
the stringand I was the currentproducedbythe stringwhena 100 ohm resistorloadwasapplied.

10. *** This value iswhenthe panel isdirectlyincidentwiththe sun.When the angle of inclinationtothe
sunwas changed,norecordable difference involtageandcurrentoccurreduntil the panel was
shadowedfromthe sun. Thisresultmaynot translate intospace andappropriate measureswill be taken
to model the scenariowhere thisisthe case.
In orderfor the solarpanelstomeetthe designatedrequirementslaidoutinthe RVM,
the solar cellsmustoperate atan efficiencyof 27%.This isthe indicatedefficiencyrating(+- 3%) by
SensorMetrix whomanufacturersthe TASC. Aslongas the cellstestedoperate withinthe allowable
limitsdesignatedbySensorMetrix theyare suitableforuse onANDESITEand will meetthe power
requirementstoprovide properbatterychargingduringin-flightoperationforatwoweekmission.
Efficiencyof aphotovoltaicsystemhasbeenarticulatedintoasimple algebraicequation
for an approximationof aratioof the conversionfromsolarradiationtoelectrical power production.
The equationisbasedoff of several variables:the surface areathe photovoltaicsystemcovers,the solar
intensityexperiencedbythe system, andthe max poweroutputof the entire system.Since
experimental datawastakenwhenthe solarpanelswere directlyincidenttothe solarradiation,the
total poweroutputvalue calculatedabove istakenasthe maximumpoweroutputof the system.Solar
intensityatAM1.5 (i.e.earthatmosphere)isrecordedas beingbetween930– 1000 W/m2
.Giventhe
weatherconditionsinBostononthe dayof testing,the solarintensitywasclose to950 W/m2
and this
value isusedto calculate the operatingefficiency.Eachcell usedhasan area of 2.277 cm2
(indicatedby
manufacturerdatasheet) resultinginatotal areaof 0.0109 m2
of photovoltaiccoverage oneachside of
the sensornode.Withthe necessaryvariablesdetermined,efficiencycanbe estimated.
ή = Pout,max / (A*Isolar) = 2.3702 W /(0.0109 m2
* 950 W/m2
)
ή = .2289 = 22.89%
The efficiencyobtained islessthan the datasheetrange indicated.Thiswouldnormally
bringconcernTASC wouldnotbe usable forthe mission,however,the cellsusedhadbeendonatedbya
previoussatelliteprojectandwere overtwoyearsold.Ithas beenrecordedinsolarcell textbooksthat
cellsdeteriorateinproductionby5%each yearindark storage.Withthistakenin mind,the cellstested
shouldonlybe operatingata maximumof 90% theiroptimal powerconsumption.Therefore,the
efficiencyisrecalculatedtodetermine the actual optimal efficiencyof the cellstested.
0.9ήoptimal = ή
ήoptimal = 22.89%/0.9 = 25.43%
The re-calculationshowsthatthe minimumoptimal efficiencyof the testingcellsdoes
indeedfall withinthe range indicatedbySensorMetrix datasheets.Withthiscalculation,itisconfirmed
that the cellsmeetthe RVMrequirementestablished.

11. 3.4 Onboard Power Consumption
There isno guarantee of a sun-synchronousorbitforANDESITEandthusno guarantee
of constantilluminationforthe solarpanelsforthe entiretyof the mission.The chance for
eclipse tooccur preventsthe solarpanelsfrombeingusedtopowerthe componentsonboard
throughan orbitand thereforLi-Pobatteriesare beingusedasthe mainpowersupplyfor
space operation.However,due tosize restrictionsof the CSDencasingthe satellite upon
launchand restraintsplacedonthe quantityof wirelesssensornodes, the sole use of an
optimal batteryforthe twoweekmission life isunfeasible.Inordertocombat these design
constraints,a combinationof photovoltaicandLi-Popowerwill be used.The Li-Poisusedto
powerthe onboardcomponentsduringmissionlifeandthe solarpanelswill keepthe battery
chargedlongenoughto operate for the extentof the mission.
As a safetymeasure,ithasbeenmade arequirementthatthe componentsbeing
poweredbythe Li-Pobatterieswill notconsume more powerperorbitthanthe solar panels
can produce.Thisrequirementisplacedinordertoensure the batteryoperatesatfull capacity
for the entiretyof the missionandcanguarantee uninterrupteddatacollectionandtransfer.
The componentsrequiredtoperformthe science experiment deliveredto the AirForce were
catalogedinan Excel spreadsheetandpowerconsumptionvalueswere obtainedfromthe
data sheetof eachcomponent.Forsafety,the maximumpowerconsumptionof eachdevice
was usedinthe productionof a powerbudget.
Each orbit requires atotal of 1.305066212 Wh of power,persensornode, tocomplete
itsorbital tasks.The breakdownof each powerconsumptionphase isalsorecordedinthe
powerbudgetspreadsheet.A MATLABsimulationof the solarpowergenerationforasensor
node inorbitindicatedaproductionof 2.0 Wh per orbitbythe solararray. Thissimulation
made the assumptionthatthe node tumbledaboutitsminoraxisasis predictedbyorbital drag
simulations. Itispossible the node will have minimal tumblingandmimicthe orbitof the
attitude controlledmule.Inthiscase,onlyone solarpanel wouldbe exposed tosolarradiation
and the simulationwasre-runtodetermine powerproductionduringthiscase.Again,the
simulationindicated2.0Wh wouldbe producedduringeachorbital period.Thisconsistencyis
reassuringandconfirmsthatpowerproductionwill be similaronaworst andbestcase
tumblingscenario.
The Air Force requiresa10% contingencyonpowerconsumptionestimatesandthusis
implementedtothe value obtainedalteringthe orbital powerconsumptionof eachnode to
1.43557283 Wh. Inadditiontothiscontingencyaccounting,the chargingcontrol chosenforthe
sensornodesoperatesat90% efficiencybasedonmanufacturingspecs.This10% cut fromthe
solarproductionreducespowergenerationto1.8 Wh being directedtothe batteryina single
orbit.Evenwiththese factorsaccountedfor,the sensornodesare still powerpositive by
0.36442717 Wh. Simulationsprove the powergeneratedbysolarcellsisgreaterthanpower

12. consumedbythe componentsusedforthe science experimentandthereforcanprovide
sufficientpowerforthe durationof the mission.Thismeetsthe otherRVMrequirements
designatedbyANDESITE.
Table 3: Orbital Power Budget for each sensor node
Note:Duty cycle is time active during one orbit Orbit
Altitude 460 km
Period 90.00 min
System
ID Description Component Power (W)
Duty
Cycle
Consumption
(Wh/orbit)
%
Power
ss_0 CDH
ATMEGA2560 0.1 100% 0.15 11.5%
ss_1 Radio
RFM228 0.2805 78% 0.33 25.1%
ss_2 Attitude
Gyroscope 0.02013 100% 0.030195 2.3%
SD Card 0.33 100% 0.50 37.9%
ADC 0.0009 100% 0.00135 0.1%
SunSensor 0.0000066 100% 0.0000099 0.0%
GPS 0.068 100% 0.102 7.8%
ss_3 Power
PIC16F1512 uC 0.000825 100% 0.000825 0.1%
3V3 LDO Regulator 0.000544 100% 0.000816 0.1%
CurrentMonitor 0.0004125 100% 0.0004125 0.0%
5V Boost Regulator 0.025 100% 0.015 1.1%
3V3 DC-DCConverter 0.06678601 100% 0.060846012 4.7%
ss_4 Magnetometer
1-AxisSensor 0.12 22% 0.04 3.1%
2-AxisSensor 0.24 22% 0.08 6.1%
Op-AmpsforSensor 0.0019305 22% 0.0006435 0.0%
Op-AmpforADC 0.002145 22% 0.000715 0.1%
ADC 0.0000099 22% 0.0000033 0.0%
Subtotal 1.25718951 1.305066212
Contingency 10% 10%
Total 1.38290846 W 1.435572833 Wh
PowerGenerated 1.8 Wh

13. 4. Conclusion
ANDESITEindicatesthree requirementsmustbe met forthe solarpanel design
to be confirmedformanufacturing.Those requirementsare listedinthe RVM
spreadsheetasthe following:the solar cellsmustproduce sufficientpowertocharge
the batteryfor the durationof a twoweekmission,these cellsmustalsooperate within
the efficiencyvaluesdeterminedbythe manufacturer,andfinally,the electrical
componentsusedonthe sensornode and mule mustnotconsume more powerthan
the solar panelscanprovide tothe battery.Afterphysical testingandcomputer
simulation,the sensornode solarpanel designhasbeenconfirmedtomeetthe three
requirementsmentionedandcanbe put forthto manufacturingforthe final production.
A solarpanel forthe mule wasnot physicallytested,butisalsodeterminedtomeetthe
RVMrequirementsforvariousreasons.The cellsusedonthe mule are fromthe same
orderof cellsusedforthe sensornode,makingit clearthese cellsoperate withinthe
efficiencylimitsof the manufacturer.Check.The powerbudgetof the mule isposted
belowanda computersimulationof the magneticallycontrolledorbitaltrajectory
indicatessufficientpowerisbeingprovidedtothe batteryfromthe solarpanel to
continue the missionfortwoweeksandgeneratesmore powerthanthe electrical
componentsconsume.Withthese conclusionsmade,productionof final paneldesigns
can be initiatedbarringanyfurthertesting.
Table 4: Mule Power Budget
Max Value
System ID Description Component Qty Voltage (V) Current (A) Power (W) Duty Cycle Wh/orbit Comments
ss_0 CDH
Beagle Bone Black BB-BBLK-000 1 5 0.46 2.3 100% 3.45
SD Card SanDisk 4GB MicroSD Card 1 3.3 0.1 0.33 100% 0.495
ss_1 Radio
Global Star 1 12 0.0166 0.1992 78% 0.233064
HopeRF RFM228 1 3.3 0.085 0.2805 78% 0.328185
ss_2 Attitude
Texas Inst ADC1285102CIMT/NOPB 2 5 0.0038 0.038 78% 0.04446
ST Micro L9958 3 5 0.03 0.45 78% 0.5265
Allegro ACS714LLCTR-05B-T 3 5 0.016 0.24 78% 0.2808
Analog Dev AD8629ARMZ-REEL 5 5 0.0025 0.0625 78% 0.073125
ON Semi CAT24C256YI-GT3 1 5 0.0024 0.012 78% 0.01404
Texas Inst SN65HVD231QDRQ1 1 5 0.014 0.07 78% 0.0819
Beagle Bone Black BB-BBLK-000 1 5 0.46 2.3 78% 2.691
Sun Sensors S8369 6 5 0.000002 0.00006 78% 0.0000702
Torque Coils 3 5 0.066666667 1 100% 1.5
Mag +Gyro IMU ADIS164888MLZ 1 3.3 0.2 0.66 22% 0.2178
GPS Novatel 1 5 0.14 0.7 100% 1.05
ss_3 Power
EPS CS-XUEPS2-60 1 0.1 100% 0.15
Subtotal 8.74226 W 11.1359442 Wh
Contingency 10% 10%
Total Power 9.616486 W 12.24953862 Wh
Generation 22.24 W 16.68 Wh (Ideal)
Break Even 11.12 W 15.012 Wh (Accounting for charger efficiency)