Minimize MaSat-1

MaSat-1 (Magyar Satellite-1)

MaSat-1 is a CubeSat project of the Budapest University of Technology and Economics, Budapest, Hungary (in Hungarian abbreviated as BME and in English as BUTE). The goal is to introduce undergraduate students to circuit design, as well as to train a sufficient number of space specialists, thus facilitating future selection processes for spaceborne developments. The mission objective is to demonstrate various spacecraft avionics, including a power conditioning system, transceiver and on-board data handling. 1) 2)

Figure 1: Photo of the MaSat-1 flight model with deployed antenna (image credit: BME)


 

Spacecraft:

MaSat-1 complies to the 1U CubeSat form factor of size 10 cm x 10 cm x 10 cm and a mass of ≤ 1 kg. The objectives of the CubeSat mission are:

• Demonstrate an EPS (Electrical Power System) designed and built by students, which includes 6 independent MPPT (Maximum Power Point Tracker) for each solar array.

• Test Lithium-Ion Polymer batteries used as energy storage in space environment

• Test a new communication system based on an ISM (Industrial, Scientific and Medical) band transceiver

• Test a packet telemetry and telecommand concept based on ESA standard (ECSS-E-70-41A)

• Demonstrate an on-board data handling system based on a single board computer using digital signal processor

• Demonstrate a semi-active magnetic stabilization system based on magnetic torquers. The attitude is sensed by: 3-axis gyroscopes, 3-axis magnetometers, 3-axis accelerometers, and sun sensors made of IR sensors.

The CubeSat has an expected lifetime of > 3 months, the EPS provides an input power of 1.2-2.2 W.

RF communications: Half-duplex implementation of the UHF band (435-438 MHz) with a data rate of > 1200 bit/s, the modulation scheme is 2-FSK, the transmit power is 200 mW, protocol: modified ESA PUS v1.


 

Launch: The MaSat-1 CubeSat was launched on Feb. 13, 2012 as a secondary payload on the maiden flight of the Vega launch vehicle of ASI and ESA. The launch site was Kourou in French Guiana. 3) 4)

The multiple payload launch encompasses a primary payload of 400 kg called LARES (LAser RElativity Satellite), and CubeSats (educational payloads) as secondary payloads, whose launch is sponsored by ESA. The free launch of CubeSats was offered by the ESA Education Office in Oct. 2007 (Announcement Opportunity) in cooperation with the Vega program. 5)

CubeSat passenger payloads: Although ESA's Education Office is providing 9 CubeSat positions on the maiden flight of Vega, only 7 CubeSats are confirmed as of December 2011 (Ref. 6). Not all universities that were preselected for the launch opportunity in June 2008, were able to deliver their CubeSat and the requested documentation. Other CubeSat projects, like SwissCube and HiNCube, decided to be launched on commercial flights.

Xatcobeo (a collaboration of the University of Vigo and INTA, Spain): a mission to demonstrate software-defined radio and solar panel deployment

Robusta (University of Montpellier 2, France): a mission to test and evaluate radiation effects (low dose rate) on bipolar transistor electronic components

e-st@r (Politecnico di Torino, Italy): demonstration of an active 3-axis Attitude Determination and Control system including an inertial measurement unit

Goliat (University of Bucharest, Romania): imaging of the Earth surface using a digital camera and in-situ measurement of radiation dose and micrometeoroid flux

PW-Sat (Warsaw University of Technology, Poland): a mission to test a deployable atmospheric drag augmentation device for de-orbiting CubeSats

MaSat-1 (Budapest University of Technology and Economics): a mission to demonstrate various spacecraft avionics, including a power conditioning system, transceiver and on-board data handling.

UniCubeSat GG (Universit√° di Roma ‘La Sapienza’, Italy): the main mission payload concerns the study of the gravity gradient (GG) enhanced by the presence of a deployable boom.

Table 1: Overview of the CubeSat passenger payloads flown on the Vega-1 mission 6) 7)

ALMASat, a microsatellite of the University of Bologna, is another secondary payload of the flight.

Use of P-POD (Poly Picosat Orbital Deployer) for the deployment of all CubeSats.

Orbit of primary payload: Circular orbit, altitude of 1450 km x 1450 km, inclination = 69.5º.

Orbit of secondary payloads: Elliptical orbit, altitude of 354 km x 1450 km, inclination = 69.5º, orbital period = 103 minutes (14 revolutions/day), eccentricity = 0.075. About 75% of the orbit is in sunlight.


 

Status of mission:

• March 2012: MaSat-1 has been continuously and fully operational since its first passes over the ground station in Budapest, Hungary. Spacecraft data - which include beautiful images of the Earth as well as telemetry data - are regularly received and all systems are operating nominally. During the first weeks of flight, the team was able to monitor the performance of the CubeSat’s electronics and sensors. The team will continue to collect data on the behavior of all systems and demonstrate the satellite’s active attitude control capability. 8)

• MaSat-1 has been transmitting data to the primary ground control station (Budapest University of Technology) and the secondary ground control station (Erd, Hungary). In addition to these domestic control stations, more than 120 radio amateurs have received the satellite worldwide. Their total contribution to the success of the mission exceeds 200, 000 data packets. 9)

- The flawless operation of the passive attitude control system made it possible to capture photographs ahead of schedule, but with this passive system only the Southern Hemisphere of the Earth may be targeted by the camera. As the first month of the mission passed, almost every mission objective was fulfilled. The flawless run of the satellite opens a new scientific and technological horizon for experiments which we plan to perform in the coming months.

- The first month of the mission was the most critical from the engineering perspective. Fortunately everything went in accordance with the highest expectations of the project. Not only did the satellite survive the first month without any error, but it also transmitted more than 20 MB of data about its operation and the space environment. What is more, MaSat-1 was classified as an OSCAR satellite by AMSAT. This classification brought a new name (MO-72) along with an inherent reputation. 10)

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Figure 2: The first Earth image of South Africa captured by MaSat-1 on March 8, 2012 (image credit: BME)

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Figure 3: MaSat-1 image of the cloudy Antarctic Ocean acquired on March 8, 2012 (image credit: BME)

• The Hungarian team received the first signals from MaSat-1 from a radio amateur in Florida less than two hours after launch, and by many others shortly after. A couple of hours later the team’s ground station in Budapest gathered the first ‘official’ satellite data which confirmed that the spacecraft is in perfect shape. 11)


 

Sensor complement: (Camera)

The on-board camera of MaSat-1 has a mass of about two Euro coins. The maximal resolution is 640 x 480 pixels. A width of 1 pixel corresponds to a distance of 1 to 10 km on the photos recorded.


1) http://cubesat.bme.hu/masat-1/?lang=en

2) http://cubesat.bme.hu/?lang=en

3) “ESA’s new Vega launcher scores success on maiden flight,” ESA, Feb. 13, 2012, URL: http://www.esa.int/SPECIALS/Vega/SEMJ8LYXHYG_0.html

4) “Vega VV01 launch campaign,” ESA, URL: http://www.esa.int/SPECIALS/Vega/SEMY64BX9WG_mg_1.html

5) Jakob Fromm Pedersen, “CubeSat Educational Payload on the Vega Maiden Flight, Interface Control Document,” ESA/ESTEC, Feb. 13, 2009, URL: http://www.ies.univ-montp2.fr/robusta/satellite/IMG/pdf/SP_GN_2009.02.13_ICD.pdf

6) “ESA’s CubeSats ready for flight,” ESA, Dec. 16, 2011, URL: http://www.esa.int/SPECIALS/Education/SEMG1C8XZVG_0.html

7) “ESA Cubs delivered for first Vega flight,” ESA, Nov. 14, 2011, URL: http://www.esa.int/esaMI/Education/SEM3L0WWVUG_0.html

8) “CubeSats satellite operations update,” ESA, March 28, 2012, URL: http://www.esa.int/SPECIALS/Education/SEM2KRGY50H_0.html

9) “Masat-1 captured the first Hungarian satellite photographs from space,” MaSat-1 Press Release, BME, March 14, 2012, URL: http://cubesat.bme.hu/data/sajtokozlemeny/masat-1_sajtokozlemeny_20120314_en.pdf

10) “MaSat News,” BME, URL: http://cubesat.bme.hu/en/hirek/

11) “Student CubeSats start talking to Earth,” ESA, Feb. 14, 2012, URL: http://www.esa.int/SPECIALS/Education/SEMR2ZYXHYG_0.html


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.