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Lituanica SAT-1Gintautas SulskusAMSAT-UK International Space ColloquiumJuly, 2014AMSAT-UK Colloquium 201426 July, 2014
Lituanica SAT-1 team is very grateful toradio amateur communityfor all support and enthusiasm!Thank You!AMSAT-UK Colloquium 201426 July, 2014
Driven by the Idea Launch the first Lithuanian satellite Take the first photo from space Stimulate collaboration between universities Raise the interest of general public Create a platform for future projects Create new opportunities for business and educationAMSAT-UK Colloquium 201426 July, 2014
The MissionArticle about the first Lithuanian satellite1.2.3.4.5.Core teamHW DevNew competitorSW DevTestingSent-off to NASALaunched by Antares, aboard CygnusEjected from ISS1.2.3.4.First contact!Comm problemsBrownoutsFinally, got under controlRe-entryDevelopmentJul 2012Oct 2013The waitImpatience9 Jan 2014 28 Feb 2014AMSAT-UK Colloquium 2014Fun 29 Jul 201426 July, 2014
Lituanica SAT-1 Architecture ARM module (OBC) Lituanica SAT-1Comms with GS, SAT control Peripherals URAT - commands, data transfer I2C - EPS control, telemetry, WDElectricalPowerSystemI2C multimasterArduinomoduleUARTARM UK Colloquium 201426 July, 2014
ARM module Arm Cortex M4F 32 bit, 192kb Ram, 92 MHz, 3.3V Downclocked Sensors Gyro, accel and magnetometer SD Card Telemetry data storage Watchdogs the link with GSAMSAT-UK Colloquium 201426 July, 2014
Helium-100 FSK/GMSK transceiver Frequencies TX: 120-150 MHz or 400-450 MHz RX: 400-450 MHz or 120-150 MHz Sensitivity: -104.7 dBm @ BER 10-3 Max bandwidth: 38.4kbps, full duplex AX.25 protocolAMSAT-UK Colloquium 201426 July, 2014
Arduino Atmega 2560V-16AU 8bit, 8MHz, 8kb RAM, 3.3V Beacon Message updates, ON/OFF Camera SD Card Photo storage Watchdogs ARMAMSAT-UK Colloquium 201426 July, 2014
Arduino Module: BeeLine Radio Beacon FM or CW modulation Frequencies 420-450 MHz Transmitter power -20 to 12 dBm Starts independently Guaranteed communicationAMSAT-UK Colloquium 201426 July, 2014
Arduino Module: Camera VGA 640x480 JPG compression Automatic exposure Manual focus (infinity) Fisheye lensAMSAT-UK Colloquium 201426 July, 2014
SelfieAMSAT-UK Colloquium 201426 July, 2014
Electrical Power System GOMSpace - NanoPower 3.3V@3A and 5V@3A fully controllable channels Predefined power modes Blackout, Brownout, Safe, Nominal Watchdogs I2C busAMSAT-UK Colloquium 201426 July, 2014
Electrical Power System: Solar Cells Silicon based Custom built Low cost Still in good conditionAMSAT-UK Colloquium 201426 July, 2014
FM Repeater TX 433.550 MHz RX 145.575, 67 Hz CTCSS Only 2 more in orbit Saudi SO50 - full time ISS - activated manually Feedback Good conn quality & pwr efficiency Simple equipment for commAMSAT-UK Colloquium 201426 July, 2014
FM Repeater PrototypeAMSAT-UK Colloquium 201426 July, 2014
Key System Requirements Fault tolerance Failures anytime, anywhere Redundant component control Via SW and HW power channels Watchdogging Power modes Safe, Nominal, Science Lightweight Network Protocol commands, packet data transferAMSAT-UK Colloquium 201426 July, 2014
Experimental Requirements Specification An attempt to leverage formal methods Requirements specification in natural language Translation to mathematical model (Event-B formalism) Stepwise refinement of SAT states Correct requirements according the mathematical model Barely scratched the surface Still highlighted some inconsistencies in requirements Time consuming, slowAMSAT-UK Colloquium 201426 July, 2014
Abstract level: Physical On/OffAMSAT-UK Colloquium 201426 July, 2014
1st Refinement: Control ZonesAMSAT-UK Colloquium 201426 July, 2014
2nd Refinement: Power ModesAMSAT-UK Colloquium 201426 July, 2014
3rd Refinement: Operational ModesAMSAT-UK Colloquium 201426 July, 2014
Implementation Decisions Good old C for SAT Keil RTX for ARM Arduino package for Atmel Ground Station Erlang Communication Lightweight UDP-like network protocol Developed in-houseAMSAT-UK Colloquium 201426 July, 2014
ARM SW Architecture Background tasks always initiated No new tasks are ever createdSchedule CMD[Received CMD]Scheduler[max 10 CMDs] All cmd’s go into schedulerCreate Runner task[Delay 0] Operations run as tasksRunnerLib StackBackground Operation Tasks(On/Off) Telemetry Housekeeping Power manager(Always ON) SchedulerAMSAT-UK Colloquium 2014Discard CMD[PowerMode FAILorOpMode FAIL]Continue with CMD[PowerMode OKandOpMode OK]Remove from Scheduler stack26 July, 2014
Success Criteria Minimal Get it launched Deploy antennae Possible problems in the first few weeksReceive radio beacon signal Nominal Establish SAT-GS communication Test FM repeaterAMSAT-UK Colloquium 201426 July, 2014
Success Criteria Maximum Satellite stabilisation Receive telemetry data Take photo Misfortune Telemetry archiving to SD card does not work (ARM module) Pleasant surprise OSCAR-78, or LO-78 award!AMSAT-UK Colloquium 201426 July, 2014
The First PhotoAMSAT-UK Colloquium 201426 July, 2014
Lessons Learned Operators struggled to use the satellite Confusing functionality: overlapping EPS and ARM power modes Poor\Lack of documentation or reluctance to read it :-) “Do it quickly and make it right later” does not work! Do not try! All timers must be configurable! Use homogeneous environments for reusability (e.g. only ARMs) Reflash optionAMSAT-UK Colloquium 201426 July, 2014
Thank You!AMSAT-UK Colloquium 201426 July, 2014
Lituanica SAT-1 Gintautas Sulskus AMSAT-UK International Space Colloquium July, 2014. AMSAT-UK Colloquium 2014 26 July, 2014 Lituanica SAT-1 team is very grateful to radio amateur community for all support and enthusiasm! Thank You! AMSAT-UK Colloquium 2014 26 July, 2014 Driven by the Idea Launch the first Lithuanian satellite Take the first photo from space Stimulate
