The CubeSat developed at the University of Liège ... - OUFTI-1
The CubeSat developed at the University of Liège ... - OUFTI-1
The CubeSat developed at the University of Liège ... - OUFTI-1
- No tags were found...
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
Mission: D-STAR in Space• 2 system-selecteddoppler-compens<strong>at</strong>edcoverage zones- ULg for control- Dynamicallydetermined• Personnal doppler –compens<strong>at</strong>ion possiblewithin <strong>OUFTI</strong>-1 coveragezone2
Exploded view <strong>of</strong> <strong>CubeS<strong>at</strong></strong>Exp. EPSEPSPumpkin OBCCOM + BCNB<strong>at</strong>teryHomemade OBCSolar CellPumpkin StructureSolar Panel3
STRU & MECHSTRUCTURE• Preliminary vibr<strong>at</strong>ions tests :Good correl<strong>at</strong>ion between FEM and experimental results(1 st frequency above 500Hz)MECHANISMS• One face dedic<strong>at</strong>ed to antennadeployment mechanism4
ADCS• Fully passive• Permanent magnet aligned withEarth’s magnetic field• Hysteretic m<strong>at</strong>erials system todamp rot<strong>at</strong>ionPerturb<strong>at</strong>ion torques Values [N.m]Gravity gradients 10 -10Aerodynamic torques 5. 10 -8Solar radi<strong>at</strong>ion pressure 5. 10 -9Magnetic torque 10 -10Magnet torque 10 -5 (1cm³ <strong>of</strong> Alnico-5)5
THER• ESATAN/ESARAD model• Active system for b<strong>at</strong>teriesSolar Cell 1B<strong>at</strong>tery• 6 days <strong>of</strong> test <strong>at</strong> Centre Sp<strong>at</strong>ial de Liègescheduled for spring 20096
Architecture (1)BCNI 2 C BusHomemade OBCPower LinesPumpkin’s OBCCOMExp. EPSAnalogMeasurementsBusEPS7
Architecture (2)8
Measurements9
EPS10
OBC (1) Main functions• Perform <strong>the</strong> initial oper<strong>at</strong>ions <strong>of</strong> s<strong>at</strong>ellite• Provide a power supply management for sub-systems• Handle telecommands from ground• G<strong>at</strong>her and store <strong>the</strong> various measurements• Send telemetry11
OBC (2) Hardware: 2 completely redundant computers• Pumpkin's OBC used as a backup, in case <strong>the</strong> o<strong>the</strong>r one fails• Homemade OBC:o Based on TI's MSP430o Comp<strong>at</strong>ible with Pumpkin's commercial OBC (FM430)o Prototype currently under <strong>the</strong> soldering iron S<strong>of</strong>tware• Use <strong>of</strong> FreeRTOS• High-level s<strong>of</strong>tware design in progress• Many subroutines and drivers already programmed12
COMD-STAR review Digital Smart Technologies for Am<strong>at</strong>eur Radio• Simultaneous voice & d<strong>at</strong>a transmission (e.g. GPS d<strong>at</strong>a)• Complete routing capacity, including roaming• 3 frequencies and 2 d<strong>at</strong>a r<strong>at</strong>es- VHF: 144 MHz (2m) 4.8 kbit/sec- UHF: 435 MHz (70cm) 4.8 kbit/sec- SHF: 1.2 GHz (23cm) 4.8 kbit/sec or 128kbit/sec13
COM (2)RxADF7021ULg frequencyGMSKOBCTCAdaptivefreq.AmpliTxADF7021User frequencyGMSKD-STARroutinesADF702114
BCN• 2 modes- CW (12 directmeasurements)- AX.25 (4800bauds from OBC)• Test in progress• GENSO comp<strong>at</strong>ible15
GND• Main st<strong>at</strong>ion <strong>at</strong> <strong>University</strong> <strong>of</strong> Liège• Backup st<strong>at</strong>ion <strong>at</strong> EuroSpace Center (Redu, Belgium)InternetD-STARrepe<strong>at</strong>ercontrolerTC/UserVHF/UHFD-STARmoduleFrequencyconverterAntenn<strong>at</strong>rackingsystemTCMissioncontrolcenterUserUserVHF & UHFD-STARmodulesD-STARrepe<strong>at</strong>erg<strong>at</strong>ewayRepe<strong>at</strong>ercoveragezoneWorldwideD-STARnetwork16
Simul<strong>at</strong>orSimul<strong>at</strong>ion <strong>of</strong> <strong>CubeS<strong>at</strong></strong> in Simulink• High-precision orbit propag<strong>at</strong>ion• Sunlight periods and access to ground st<strong>at</strong>ion• STK valid<strong>at</strong>ionGoal: Oper<strong>at</strong>ional simul<strong>at</strong>or⇒ Include subsystem models (ADCS, EPS, COM, & THER)17
TimelineSept.FebruaryMid-MarchMayJulyNov.2008-2009New team<strong>of</strong> 13 studentsBreadboardEngineeringmodelFlight modelto be testDelivery to ESAVEGA Maiden flight18
Conclusions (1)• Mission & use <strong>of</strong> D-STAR in Space fully defined• Space segment :• Coding and decoding <strong>of</strong> D-STAR on MSP430 demonstr<strong>at</strong>ed• All subsystems in various phases <strong>of</strong> design & construction• Breadboard & engineering models on track• Tests scheduled for May 2009 <strong>at</strong> Centre Sp<strong>at</strong>ial de Liège• Ground segment :• Tracking st<strong>at</strong>ion fully designed• Critical equipments ordered• Link from mission control center to D-STAR repe<strong>at</strong>er proven feasible• Mission control center under development19
Conclusions (2)• Many inov<strong>at</strong>ive ideas:• Use <strong>of</strong> D-STAR in space• redudant OBCs, BCN• experimental digital EPS• Tight schedule• 13 students and 6 academics• Strong academic, am<strong>at</strong>eur-radio & industrialsupport20
And worldwide visibility !21
Thanks for your <strong>at</strong>tention !22
ContactsAmandine DenisAmandine.Denis@ulg.ac.be<strong>OUFTI</strong>-1 Project ManagerAerospace and Mechanical Dept.<strong>University</strong> <strong>of</strong> Liège1, Chemin des Chevreuils (B52/3)4000 Liege, BelgiumTel : +32 (0)4 366 95 35<strong>OUFTI</strong>-1, <strong>the</strong> first Belgian nanos<strong>at</strong>ellite:http://www.oufti.ulg.ac.be23
Change language