LituanicaSat-1 (LS-1) is the first Lithuanian satellite mission. The primary mission objective is to provide university students and young engineers knowledge and real hands-on experience in satellite engineering thereby helping to develop infrastructure and know-how in space technology by interdisciplinary interaction between academia and industry in Lithuania. 1) 2) 3) 4)
The LituanicaSat-1 main project team members or partners are: IEP (Innovative Engineering Projects), a non-profit organization (founded in 2011 to promote science, technology, education and math (STEM) subjects among students and young engineers and to stimulate engineering innovations in the country) and the University of Vilnius, Lithuania. The PIs (Principal Investigators) of the mission are: Laurynas Maciulis and Vytenis Buzas of IEP and Linas Bukauskas of the University of Vilnius.
The mission objectives are:
- To launch the first Lithuanian satellite into the Earth orbit
- To carry out the first space exploration experiments for Lithuania
- To test in space the technologies created by Lithuanians
- To test renewable energy sources in space
- To create new opportunities for business and education
- To improve collaboration between Lithuanian scientists from all over the world
- To take the first Lithuanian pictures from space
- To start Lithuania's journey to the outer space.
• LituanicaSat-1 studies FM Voice Repeater operation in Low Earth Orbit. Its key purpose is to extend the radio communication distance between two radio amateurs from several to several thousand kilometers.
• LituanicaSat-1 examines a silicon based custom built solar cell. Successful demonstration of this technology will prove the feasibility of a lower cost solar cell application for nanosatellites.
• LituanicaSat-1 tests redundant open source hardware and software based on different microcontroller architectures. The predominant use and successful demonstration of open source technology, such as Arduino, offers new ways to make space technology more affordable to general public.
• LituanicaSat-1 takes pictures of the Earth and downlinks the data to a ground station network.
• LituanicaSat-1 also tests various types of attitude sensors.
Table 1: Some background on the development of LituanicaSat-1 5)
LituanicaSat-1 conforms to the standard 1U CubeSat form factor of size 10 cm x 10 cm x 10 cm and a mass of 1 kg. The CubeSat was build at Innovative Engineering Projects, NPO of Jonava, Lithuania. The satellite does not have any active systems except the antenna deployment mechanism that is engaged 30 minutes after deployment sequence. Both attitude and thermal control subsystems are implemented passively for simplicity and safety.
Figure 1: Photo of the LituanicaSat-1 CubeSat (image credit: LS-1 team)
ADCS (Attitude Determination and Control Subsystem): A passive ADCS is used consisting of permanent magnets that create a control torque and soft magnets that provide dampening torque using hysteresis effect. The following attitude sensors are implemented for attitude determination:
- PS-MPU-6000A MEMS motion sensor
- PS-MPU-9150A MEMS motion sensor
- L3GD20 MEMS three-axis digital output gyroscope
- HMC5883L three axes digital magnetometer.
CDHS (Command and Data Handling Subsystem): There are two on board computers in LituanicaSat-1 due to redundancy requirements: the flight computer is based on the ARM Cortex-M4F microcontroller; the secondary (back-up) computer is based on the Arduino ATMega 2560 microcontroller. These 2 computers and their periphery are laid out on different sides of one shared PCB (Printed Circuit Board). The flight computer is the central control unit of the satellite responsible for maintaining the normal operating mode of the satellite, monitoring and control of energy resources, control of attitude determination sub-system and performance of telecommands received from the satellite ground station in Lithuania.
The LituanicaSat-1 team developed the secondary flight computer based on the open source hardware and software project named Arduino. This computer will ensure limited, however safe functionality of the satellite in case of failure of the main onboard computer and will also take and record the first pictures made by Lithuanians from space as well as control the radio beacon of the satellite.
EPS (Electrical Power Subsystem): The EPS includes a GomSpace Nanopower P31us power board with a lithium-ion battery and solar cells. This subsystem is intended for ensuring continuous supply of electricity to all components of the satellite. When the satellite is in the sunlight, the electricity will be produced by the solar cells developed in Lithuania and attached to all six outer walls of the satellite body. As the satellite enters the shadow of the Earth, electricity accumulated in the lithium-ion battery during sunlight will be used.
Figure 2: Photo of the GomSpace EPS (image credit: GomSpace)
All sides of the CubeSat are covered externally with body mounted (non-deployable) solar panels. Each solar panel is made of silicon solar cells laid on glassfiber-epoxy pad and covered by special transparent epoxy resin. The satellite's external silicon monocrystalline-based solar panels were specially built and donated by the Lithuanian based R&D company PrecizikaMET SC.
RF communications subsystem: This subsystem consists of a transceiver and antennas. The He-100 COTS transceiver is used on LituanicaSat-1. This radio device performs a very important and complex function during the mission – to establish and maintain radio communication with the satellite the ground station. This is one of the most complicated tasks in the mission, because the satellite will fly above Lithuania at a great speed for approximately 5 minutes. During that time the project will have to download important telemetry data of the satellite while having very limited energy resources available and to transmit telecommands back to the satellite. The key technical specifications of the radio transceiver are as follows:
- Operating frequencies: Transmission: 437 MHz (UHF), reception: 144 MHz (VHF)
- Sensitivity: -104.7 dBm @ BER 10-3
- Transmit power: 100 mW – 2 W
- Receive power: < 200 mW
- Data transfer rate: 9.6 kbit/s
- Data protocol: AX.25
- Operating temperature: from -30 to +70oC
There are 4 monopole antennas on LS-1: three UHF antennas and one VHF antenna. Each antenna is made of approx. 0.2 mm thick and 5 mm wide spring steel measurement tape. In deployed configuration, all UHF antennas are pointed towards the Z+ body axis direction and VHF antenna is pointed toward the –Z body axis.
Figure 3: Photo of the FM transponder (image credit: LS-1 team)
Motherboard: The motherboard of the satellite has inbuilt important equipment for performing critical functions at the time of the satellite deployment, such as powering on the satellite and unfolding of radio communication antennas. The interfaces required for servicing the satellite on the ground are also connected to the motherboard.
Figure 4: Photo of the motherboard (image credit: LS-1 team)
Figure 5: Block diagram of the LituanicaSat-1 (image credit: LS-1 team)
Figure 6: Overview of the LituanicaSat-1 CubeSat structure (image credit: LS-1 team)
Figure 7: NanoRacks-LituanicaSat-1 team members during a presentation at Vilnius University (image credit: Vilnius University)
Launch: The LituanicaSat-1 CubeSat was launched as a secondary payload on the Cygnus CRS-1 (Cargo Resupply Mission-1) on January 9, 2014 (18:07:05 UTC) on an Antares-120 Vehicle of OSC from MARS (Mid-Atlantic Regional Spaceport), Wallops Island, VA. 6)
Cygnus CRS Orb-1 is the second flight of the Orbital Sciences' unmanned resupply spacecraft Cygnus, its second flight to the ISS (International Space Station) and the third launch of the company's Antares launch vehicle. 7) 8)
The cargo craft was loaded with 1261 kg supplies for the station, including vital science experiments to expand the research capability of the Expedition 38 crew members aboard the orbiting laboratory, crew provisions, spare parts and experiment hardware. - Also aboard the flight are 23 student experiments that will involve more than 10,000 students on the ground. These experiments will involve life sciences topics ranging from amoeba reproduction to calcium in the bones to salamanders.
The secondary payloads (34 CubeSats, commercial payloads of Orbital Sciences) on the Cygnus CRS-1 mission were:
- ArduSat-2, a 2U CubeSat (2 kg), a crowd-funded project of NanoSatisfi LLC.
- LituanicaSat-1, a CubeSat of IEP (Innovative Engineering Projects) and the University of Vilnius.
- LitSat-1, a 1U CubeSat of LSA (Lithuanian Space Association) and of KTU (Kaunas University of Technology), Kaunas, Lithuania.
- SkyCube, a 1U CubeSat, a crowd-funded project of Southern Stars Group LLC, San Francisco, CA, USA.
- UAPSat-1, a 1U CubeSat of UAP (Universidad Alas Peruanas), built by INRAS-PUCP (Institute for Radio Astronomy of the Pontificia Universidad Católica del Perú), Lima, Peru.
- Flock-1 fleet of 28 satellites (all 3U CubeSats) of Planet Lays Inc. of San Francisco, CA. Flock 1 is designed to deliver frequent, low-cost and high-resolution imagery of the planet that could help monitor deforestation, track natural disasters and benefit humanity in a number of other ways. All Flock-1 nanosatellites provide imagery with a resolution of 3-5 m.
All CubeSats will be using the NanoRacks deployer system on the ISS. They are deployed using the J-SSOD ( JEM Small Satellite Orbital Deployer). The NanoRacks
The NanoRacks CubeSats are delivered to the ISS already integrated within a NRCD (NanoRacks CubeSat Deployer). A crew member transfers the CubeSat from the launch vehicle to the JEM. Visual inspection for damage to the NRCD unit is performed. When CubeSat operations begin, the NRCDs are unpacked, mounted on the JAXA MPEP (Multi-Purpose Experiment Platform) and placed on the JEM airlock slide table for transfer outside the ISS. A crew member operates the JEM RMS (Remote Manipulating System) – grapple and position for deployment and CubeSats are deployed when JAXA ground controllers command a specific NRCSD.
Figure 8: Photo of the NRCD (NanoRacks CubeSat Deployer) with the loaded CubeSats in the launcher bay (imagecredit: NanoRacks LLC)
Orbit: Near-circular orbit of the ISS, altitude of ~400 km, inclination of 51.6o.
Sensor complement: (Camera)
The requirements called for a COTS camera of low mass and low power consumption along with an on-board processing & compression capability and compatibility with Arduino controllers.
• A LinkSprite JPEG color VGA (Video Graphics Array) camera was selected for flight with the following specifications:
- JPEG image compression
- 3.3 -5 V power supply
- Size 32 mm x32 mm
- Current consumption: 80-100 mA
• A custom 7075-T6 aluminum housing was manufactured to replace the plastic housing
• The original narrow FOV lens was replaced by a 131o FOV wide angle lens.
Figure 9: Photo of the onboard camera (image credit: LS-1 team)
• The LituanicaSat-1 CubeSat reentered Earth's atmosphere on July 28, 2014 (Figure 10). The project lost contact with the CubeSat during the last pass over our ground station the night before reentry at 20:42 UTC on July 27, 2014. 9)
• On May 21, 2014, Vilnius University presented some images of LituanicaSat-1 to the public. The COTS camera demonstrated its operation in space. 10)
Figure 11: The first Earth image of LituanicaSat-1 was acquired on May 2, 2014 (image credit: LS-1 team)
• The global radio amateur community provided far more data to the LituanicaSat-1 project than all the ground stations used for the mission (Figure 12).
Figure 12: Ground station versus ham access (image credit: LS-1 team)
• Communication system troubleshooting (Figure 13).
- Uplink budget proved to be less favorable than estimated during design (reliable uplinks were possible only using RF amplifier with 100 W of output power)
- Downlink and uplink instability due to tumbling and spinning of the CubeSat.
Figure 13: Signal field strength graph from LituanicaSat-1 during one ot the image download sequences showing signal fading due to satellite spin (image credit: Mike Rupprecht, DK3WN)
- Negative power budget was quickly identified as the cause of the problem
- Solar panel voltages appeared to be nominal (as per ground test results)
- EPS under voltage protection prevented from critical failure but did not solve the problem
Solution: reduce power draw by turning off non critical sub-systems until Vbat>Vnormal (proved to be not so easy as it sounds).
Figure 14: Battery voltage during the first days after deployment (image credit: LS-1 team)
• On Feb. 28, 2014, the first FM beacon signal heard by DK3WN at 08:45:00 UTC.
• The LituanicaSat-1 was deployed from the ISS on February 28, 2014 at 7:30 UTC.
Figure 15: Photo of the deployment of LituanicaSat-1 and other CubeSats from the JEM/Kibo module of the ISS (image credit: NASA)
1) "What is LituanicaSat-1," URL: http://www.kosmonautai.lt/en/mission/what-is-lituanica-sat-1/
2) L. Maciulis, L. Bukauskas, V. Buzas, M. Dvareckas, Z. Batisa, Z. Atkociunas, G. Sulskus, S. Kareiva, V. Valeitis, K. Petrauskas, F. Pavlov, "LituanicaSat-1: lessons learned from the first Lithuanian satellite mission," 6th European CubeSat Symposium, Estavayer-le-Lac, Switzerland, October 14-16, 2014
3) "NanoRacks-LituanicaSat-1 (NanoRacks-LituanicaSat-1)," Sept. 17, 2014, URL: http://www.nasa.gov/mission_pages/station/research/experiments/1329.html
4) "LituanicaSat-1 Lithuanian CubeSat," AMSAT UK, Feb. 27, 2014, URL: http://amsat-uk.org/2014/02/27/lituanicasat-1-cubesat/
5) "Customer Case Study: LituanicaSat-1," NanoRacks, URL: http://n-avionics.com/2/wp-content/uploads/2015/01/Customer_Case_Study_LituanicaSat1.pdf
6) Trent J. Perrotto, Josh Byerly, "New Science, NASA Cargo Launches to Space Station Aboard Orbital-1 Mission," NASA, Release 14-009, URL: http://www.nasa.gov/press/2014/january/new-science-nasa-cargo-launches-to-space-station-aboard-orbital-1-mission/#.Us98i_uFf_o
7) "CRS Orb-1 Mission," Orbital, URL: http://www.orbital.com/newsinfo/missionupdates/orb-1/files/Mission%20Overview.pdf
8) "Lithuania's First Satellite to Send Greetings from Space," Astrowatch, January 25, 2014, URL: http://www.astrowatch.net/2014/01/lithuanias-first-satellite-to-send.html
9) Information provided by Laurynas Maciulis of IEP and Research Fellow at Vilnius University Faculty of Mathematics and Informatics, Vilnius, Lithuania.
The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: "Observation of the Earth and Its Environment: Survey of Missions and Sensors" (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (firstname.lastname@example.org).