Baumanets-2 (Microsatellite of Bauman University, Moscow)
Baumanets-2 is a follow-up microsatellite mission of Bauman Moscow State Technical University (BMSTU), Moscow, Russia. The educational goals of the Baumanets-2 microsatellite project aim at training students through a full life cycle of satellite creation, in-orbit operation and implementation of scientific and educational programs through conducting scientific experiments onboard. Specific goals of the project are: 1)
- Training of high-qualified professionals for the aerospace industry
- Conduction of scientific experiments in space in fundamental and applied areas
- Implementation of practical technical solutions
- Motivation of student interest towards scientific research, education quality improvement in fundamental disciplines
- Enabling hands-on experience in the design, building, testing and operation of a real spacecraft.
Table 1: Some background on the development of the Baumanets-1 microsatellite 2)
Figure 1: The Baumanets-1 microsatellite and some members of the development team (image credit: BMSTU)
In spite of all mishaps, a new Baumanets-2 microsatellite has been developed by students of BMSTU (Bauman Moscow State Technology University). The spacecraft structure consists of a regular hexagon 460 mm in diameter and 530 mm high in its folded state. The bottom plate shape is f hexagonal. It is used to attach the satellite to the adaptor/separation system. It houses separation system fittings, a ribbon antennae linked to the onboard control system and an information-transfer system antenna. 3)
The upper plate is also hexagonal in shape. It houses the propulsion system, the digital solar sensors, the Glonass/GPS antennae and the GlobalStar antenna. Digital solar sensors are attached to the upper plates with special fittings, ensuring their position in relation to the microsatellite axis. In order to avoid mutual shadowing, all antennae are installed on a common truss in the same plane with micro-engines unit.
Figure 2: Illustration of the Baumanets-2 microsatellite (image credit: Bauman University)
The microsatellite design peculiarity lies in the unified structure of the service system units, the payload (onboard computer, GlobalStar modem) and the optical camera. All units are assembled into one frame, which is attached to the upper and bottom plates. The relative position of the units on the frame is defined by the thermal footprint of the units and their connections. Units have attachment ports from both sides. Cables, which connect the units, are bundled together in two cable manifolds, which are attached to the leads. The leads connect together the corresponding corners of the upper and bottom plates. Unit's ramp is attached to the upper and bottom plates with four bolts, two leads and two 3 mm plates to ensure the stiffness of the structure and provide for heat transfer, i.e. equalize the temperature in the instrument bay. These plates include ample areas for convection heat transfer and for dumping of excess heat into space. Areas between the plates, the ramp and the units can be filled with spacers made of heat-transfer material based on thermally processed graphite. Two plates are attached to the side panels of the units and to the ramp.
One of the plates houses the “W-band Experiment" unit with a horn antenna, in the area between the solar panels and the unit's ramp. The horn antenna is aligned along the linear axis of the microsatellite. The required angles of deflection from nadir - as required during the experiments - are ensured by programmed turns of the microsatellite with the help of an attitude control system. Adaptors on the side of the units ramp are covered only with a multi-layer thermal protection cover, which ensures easy access to the adaptors during the tests.
The solar panels of the microsatellite feature gallium arsenide photo-electric transducers and are built on milled plates. Solar panels are folded in transportation position around the instrument bay in the hexagonal shape. The solar panels are secured in folded position with the help of two mechanical locks. They are unfolded by two electro-mechanical servo-mechanisms with rods, activated by a command signal from the on-board control system. Each servo-mechanism opens its solar wing consisting of three panels. The unfolding of the solar panels into a flat plane and the folding of the panels back into a hexagonal shape may be conducted many times. This increases the power of the energy system in case of normal operation and orientation of the micro-satellite to the sun, and improves survivability of the satellite if a loss of attitude occurs. All units of the microsatellite are covered with conducting materials and metal links.
Launch: A launch of Baumanets-2 is scheduled as a secondary payload for Q2 2014 on a Soyuz-2.1b Fregat vehicle from the Baikonur Cosmodrome, Kazakhstan. The primary payload on this flight is Meteor-M-2.
The Soyuz delay follows a two-year grounding of the Russian-Ukrainian Dnepr silo-launched rocket, which small-satellite owners hope may now be returning to the market pending an agreement between Russia’s military space forces and the Russian space agency, Roscosmos.
The secondary payloads on this flight are:
• Baumanets-2, a technology microsatellite (~100 kg) of BMSTU (Bauman Moscow State Technical University)
• Monika-Relek (or MKA-PN2), a Russian microsatellite (solar and magnetosphere research), built by Lavochkin, Russia.
• DX-1 (Dauria Experimental-1), the first privately-built and funded Russian microsatellite (22 kg) of Dauria Aerospace, equipped with an AIS (Automatic Identification System) receiver to monitor the ship traffic. 4)
• TechDemoSat-1 of SSTL, UK with a mass of ~160 kg
• UKube-1, a nanosatellite of UKSA.
• M3MSat, a microsatellite (85 kg) of CSA / COM DEV, Canada.
• SkySat-2 of Skybox Imaging Inc. of Mountain View, CA, USA, a commercial remote sensing microsatellite of ~100 kg.
• AISSat-2, a nanosatellite with a mass of 6.5 kg of Norway (built by UTIAS/SFL of Toronto).
• Venta-1 / V1-QSPnP1 (V1-QuadSat-PnP-1) the first nanosatellite (7.5 kg) project of Latvia built by LatSpace SIA of Ventspils.
Orbit: Sun-synchronous orbit, altitude = 820 km, inclination = 98.8º, LTDN (Local Time on Descending Node).
Sensor/experiment complement: (FRP, Camera, W-band experiment)
FRP (Franco-Russian Payload):
The FRP is a radiation analysis experiment developed by students of UM2 (Montpellier-2 University) of France. The experiment consists of flying integrated circuits in bipolar technology and measure the radiation induced degradation over the mission duration. In-flight data will be compared to the results obtained by means of a prediction method developed at the University Montpellier-2 and currently being validated by ESA and CNES (Ref. 3).
Background: A Franco Russian student project, FRIENDS, has been recently undertaken. In this project, the Franco-Russian Payload aims at flying a radiation effect experiment designed by the University of Montpellier on the Baumanets-2 satellite of the Bauman Moscow State Institute.
The FRIENDS project was born from the common will expressed by French and Russian governments to have students from both countries work on a common space project. Bauman Moscow State Technical University (BMSTU) was chosen on the Russian side for its long experience and high technical level in space technologies. On the French side, the French space agency CNES (Centre National d’Etude Spatiales) selected UM2 (University Montpellier 2) that benefits from a three-year experience in space technology by working on the ROBUSTA (Radiation on Bipolar University Satellite Test Application) picosatellite. The ROBUSTA CubeSat of UM2 is scheduled to fly on the maiden flight of the Vega launch vehicle of ESA in 2011 from Kourou.
In April 2009, a French delegation visited Bauman. Both parties met again in Paris in October 2009. During this last meeting, it was agreed that the ROBUSTA payload should be adapted as a FRP (Franco Russian Payload) onboard the Baumanets-2 microsatellite designed by the Bauman Youth Space Center, and that a collaboration would be undertaken on the ground stations. When this stage of the project is successfully completed, it might be decided to carry on this collaboration with a much more ambitious project.
FRP experiment: Concern of radiation-induced degradation on bipolar transistors and integrated circuits was raised in the 1960s. Early studies focused on gain degradation due to neutron irradiation. More recently, attention was paid to the gain degradation due to TID (Total Ionizing Dose). In 1991, the first report of Enhanced Low Dose Rate Sensitivity (ELDRS) on irradiated bipolar transistors was published. 5)
It was found that in some bipolar devices, the current gain degradation induced by a given TID was much higher if the dose was deposited slowly (low dose rate) than quickly (high dose rate). This phenomenon has an important impact on the hardness assurance of space systems, since ground-based testing, typically performed at high dose rates, may underestimate the real low dose rate degradation on the mission lifetime encountered in actual missions. An example of the phenomenon is shown in Figure 3. The electrical parameter decreases at low dose rates, approaching those encountered in space. The higher dose rates, corresponding to testing range (at ground) underestimate the degradation. The “inverted S-shaped curve” obtained is characteristic for the degradation as a function of the dose rate.
Figure 3: Normalized current gain for a PNP bipolar transistor irradiated to a total dose of 20 krad versus dose rate (image credit: UM2)
Hence, developing hardness-assurance and test methods addressing the concern of ELDRS has constituted a major challenge during the last few years. The aim is to predict at ground level, in a fairly short time (at least one month), the behavior of a device with a planned design life of 15 years on-board a spacecraft.
At the University of Montpellier, the Radiation & Components research group has proposed a new approach for bipolar devices testing. The new approach is closer to physical effects that are taking place during a space mission, and the preliminary results obtained are very promising. The concept is based on a “switching experiment” that corresponds to a two-step experimental procedure: first a high dose rate irradiation, to be followed by a low dose rate irradiation. 6) 7)
To propose a new testing method that can be used by satellite manufacturers a large amount of experimental data is needed for a large variety of devices. ESA and CNES have initiated a 36 month experimental campaign, run by the Austrian Research Centers GmbH (ARC Research Center) which is supported by ESA. This method is considered the proper way taking into account the ELDRS considered as a major concern for Radiation Hardness Assurance. The FRP will collect data in flight that will help to validate the method.
The FRP experiment consists in flying two different analog integrated circuits, the voltage comparator LM-139 and the voltage amplifier LM-124, both with date codes known to exhibit ELDRS and very strong degradation. The degradation of key parameters (Iin+, Iin-, Icc+, Icc-, Voutmax, Voutmin) will be recorded on a 12 hour basis and compared to the predictions issued from a new ground based test method.
In addition, the dose received by the devices during the last 12 hours and the temperature will also be recorded. TID (Total Ionizing Dose) will be monitored using a novel sensor based on OSL (Optically Stimulated Luminescence) jointly developed by IES-UM2 (Institut d’Electronique du Sud -UM2) and CNES. This sensor is identical to the Carmen-2 (Environment Characterization and Modelisation-2) instrument, flown on the Jason-2 mission (launch June 20, 2008).
The FPR includes a payload board identical to the payload designed for the ROBUSTA CubeSat. One of the main interests of the FRP project is to fly this board on Baumanets-2 prior to the launch of ROBUSTA, in order to validate the concept and the design. It was then decided to use the FRP as an interface equipment between Baumanets-2 and the ROBUSTA payload. The interfaces of power supply, numerical data, and mechanical structure have been addressed thanks to a very fruitful collaboration between French and Russian teams.
As shown in Figure 4, the power supply is used convert the voltage (12 V) from the Baumanets-2 CTS into the + 6 V and – 5 V supply voltages needed to operate the ROBUSTA payload.
The FRP is then composed of a motherboard integrating the numerical and power supply interfaces which are plugged to the ROBUSTA experiment board, a controller board (EOBC) and a third board for the interface connectors as shown in Figure 5.
Figure 4: Overall architecture of the FRP (image credit: UM2, CNES)
Figure 5: Schematic view of the FRP mother board and connectors (image credit: UM2, CNES)
A remote sensing camera is installed onboard enabling to acquire 30 m resolution images. Satellite images are planned to be used in ecological monitoring, oil pipelines monitoring, forest fires detection etc.
A description of the camera is not available.
The objective is to measure the signal attenuation for very low acquisition angles. The experimental results will be used for future high-speed communication system development between a spacecraft and ground stations. Bauman University radio telescopes will be used as ground stations for receiving data in this experiment. A GlobalStar modem will be installed onboard the spacecraft to confirm the possibility to transmit telemetry data via the commercial GlobalStar network in LEO and the ground stations.
1) Vera Mayorova, Kirill Mayorov, “Earth Remote Sensing as an effective tool for the development of advanced innovative educational technologies,” Proceedings of the 59th IAC (International Astronautical Congress), Glasgow, Scotland, UK, Sept. 29 to Oct. 3, 2008, IAC-08-E1.4.3
2) Victoria Mayorova, “Baumanets student micro-satellite,” UNIVERSAT 2006, International Symposium on Space Education, June 26-30, 2006, Moscow, Russia, URL: http://crdlx5.yerphi.am/files/Conferences/2006/mayorova.pdf
3) L. Dusseau, N. Roche, R. Badsi, S. Perez, S. Jarrix, J. Boch,C. Deneau, M. Bernard, J-R. Vaille, V. Muravyev, K. Mayorov, V. Mayorova, M. Saleman, A. Gaboriaud, “A Franco-Russian Academic Radiation Effects Payload onboard Baumanets-2,” Proceedings of the Symposium on Small Satellite Systems and Services (4S), Funchal, Madeira, Portugal, May 31-June 4, 2010
4) “Dauria Aerospace and Samsung will launch the first in Russia private artificial satellite of the Earth,” Oct. 15, 2013, URL: http://all-rss.com/item-1070741-dauria-aerospace-and-samsung-will-launch-the-first-in-russia-private-artificial-satellite-of-the-earth/#.UwSE3s7ihqM
5) S. Perez , C. Deneau, N. J¿H. Roche, M.P. Bernard, “Concepts of modularity and standardization for small satellites,” Proceedings of the 61st IAC (International Astronautical Congress), Prague, Czech Republic, Sept. 27-Oct. 1, 2010
6) J. Boch, F. Saigné, R.D. Schrimpf, J. R. Vaillé, and L. Dusseau, “Estimation of Low Dose Rate Degradation on Bipolar Linear Integrated Circuits Using Switching Experiments,” IEEE Transactions on Nuclear Science, Vol. 52, 2005, pp. 2616 - 2621
7) J. Boch, “Effect of Switching from High to Low Dose Rate on Linear Bipolar Technology Radiation Response, “ IEEE Transactions on. Nuclear Science, Vol. 50, 2004, pp. 2896-2902
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.