THE PROCEEDINGS BOOK

Transcription

УДК 629.79
ББК
THE PROCEEDINGS BOOK
SMALL SATELLITES, THEIR SYSTEMS
Small satellites, their systems and subsystems, mission concepts and related infrastructure: the proceedings book. – Blagoveshchensk: AmSU, 2014. – 108 p.
AND SUBSYSTEMS, MISSION CONCEPTS
AND RELATED INFRASTRUCTURE
Small satellites students’ innovation Forum
of the Association of Sino-Russian technical universities
The book includes the proceedings of the ASRTU Small satellites students’ innovation Forum held at the Amur State University on April 11th 2014.
April 11th 2014
ISBN 978-5-93493-211-5
Blagoveshchensk
AmSU
3
© Amur State University, 2014
2014
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HISTORY AND PERSPECTIVES OF DESIGN
Small satellites students’ innovation Forum
OF MICRO-SATELLITES IN MAI
of the Association of Sino-Russian technical universities
Medvedsky A. L., Firsyuk S. O.
Moscow Aviation Institute (National Research University)
e-mail: [email protected]
The space-rocket technology was introduced in MAI by S. P. Korolev,
V.P. Mishin, and M. K. Tikhonravov in 1959. The new industry needed the specialists,
therefore in 1959 a new department No.102 «Structural Design of Flying Vehicles» being a kernel of the up-to-date Faculty of Aerospace Technologies was organized and
headed by the academician V. P, Mishin up to the 1990. Form the 1974 V. P. Mishin
was the staffer of Moscov Aviation Institute.
The Student Design Bureau for Small Satellites «Iskra» was organized in the Department No. 102 (from the 1968 – No. 601) at the autumn of 1967. The students have
several projects developed. 28.04.1976 by the Governmental Enactment the development of educational and experimental satellites was launched. The «Iskra» design bureau
has developed the micro-satellite of fourth variant (I-4A).
26.10.1978 the micro-satellite «Radio-2» (I-4A) being the first university satellite
and the first in USSR non-hermetic satellite has been succesfully launched (the passing
launch togeher with the satellite «Cosmos-1045» by the launcher «Cyclone-3»).
10.07.1981 the next satellite «Iskra» (I-5) was launched. The satellites of the second
generation were designed for the launch from the «Salyut-7» orbital platform. Two I-6
satellites were launched, «Iskra-2» (17.05.1982) being the first artificial satellite
launched from the manned spaceship, and the «Iskra-3» (18.11.1982).
From the mid-eighties the further design of micro-satellites was proceeded. At the
beginning of the nineties form the «Mir» orbital platform two miro-satellites were
launched, «MAK-1» (17.06.1991) and «MAK-2» (20.11.1992). Several interesting
projects such as the satellite with cable system, the satellite with the aerodynamical
brake systam and some others were not realized later due to the worsening of the
economic situation in Russia.
From the mid-2000’s at the Aerospace Faculty the further program needed for
both education and scientific activity development was launched. The Faculty
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Development Program for 2009-2013 provides the organization of the Resource Center
and launch systems for micro-satellites are proposed as well as the intrinsic satellite-
of Space and Rocket Technology as an unified research, experimental and industrial
borne hardware, energy systems, software, and technical vision as well as systems of
complex with modern equipment. As a target for the Resource Center a life cycle of
automatic control.
small space vehicle was choised. Therefore the synergy effect in the quality of education
can be reached. Two other directions are lied with the DPLA and the use of the spatial
activity results. This program was experted and approved by Roskosmos.
«Iskra» cooperates in several common projects such as the Condor-UNAM-MAI,
«RadioScaf» and others including the university educational complex «SOVIC».
The complete realization of the development program of the faculty of Aerospace
The organization of the industrial and test center for small space vehicles in MAI
Technologies allows one the design of small spatial vehicles equipped by modern satel-
after 2-3 years with the costs needed to order one satellite provides the real possibility to
lite-borne instruments needed for the basic and applied researches in university and ts
stand as the all-Russian leader because of the unprofitability of the design and
cooperation with Russian and foreign partners, flying qualification of perspective mod-
production of small satellites on the basis of the leading industrical enterprises due to the
ern satellite-borne instruments, and practical tests of various constructive decisions and
overhead expenses and oversized experimental base.
materials.
Tha avaliable and developed stand base of MAI allows one the ground tests of
small satellites up to 100 kg so that is optimal for most planned spatial programs. The
wide co-operation of faculties of MAI allows one the design and production of small
space vehicles in MAI on the groundwork of only universitary base.
The «Iskra» design bureau develops now some new projects of micro- and nanosatellites (fig 1, 2).
Fig. 1. Condor-UNAM-MAI.
Fig.2. Nano-satellite 601-Х-1.
The «Iskra-7» is the nano-satellite of optimal «cost-effectiveness». The costs of
the university nano-satellite must be reduced down to 0,25...0,5 millions of roubles for 1
kg mass form the contemporary 1...2 millions; the radiation protection of the work load
by the frame, electric power up to 6...7 W and coefficient of efficacy 14-15% must be
secured as well as the use of serial circuit boards of various industry standards and the
use of optical must be provided. Also the CubeSat satellites are developed, the frames
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THE DEVELOPING ROAD OF SMALL SATELLITES
IN HARBIN INSTITUTE OF TECHNOLOGY
In the center, 28 full time staffs, including 10 professors, are belongs to four research groups: spacecraft system design and simulation, avionics miniaturization, guidance navigation and control, system structure and dynamics. More than 20 postgradu-
Wang Feng
Research Center of Satellite Technology, Harbin Institute of Technology, Harbin,
150001, China, e-mail: [email protected]
HIT and RCST
ates, including Msc and PhD students, will graduate from center each year. There are five
laboratories related to the technology of small satellite development. The ground station
has been used to control the satellite directly. So far, three satellites, named Shiyan-1, Shiyan-3 and Kuaizhou-1, have been developed in RCST.
Founded in 1920, Harbin Institute of Technology (HIT), with science, engineering
Shiyan-1 Satellite
and research as its core, encompassing management and liberal arts, economy and law,
is now developing into an open, multi-disciplinary and world-class university. There are
3447 full-time faculties and 47786 enrolled students in 3 campuses.
As a nationally recognized university that develops satellites, three small satellites
have sparkled in the sky one after another, fully demonstrating the hidden innovative capability and advantages in universities as well as their capabilities in organization, im-
Early in 1998, HIT took the lead in independently developing the satellite Shiyan1 (Test satellite), which was launched on April 18th , 2004. The satellite mass is 204 kg,
running in 600km SSO orbit. It was China's first transmission-type small satellite and
first experimental digital imaging system capable of three line array stereoscopic terrain
mapping by using small satellite. The satellite was, officially, mainly to be used to carry
plementation and quality assurance for major national projects. It fully embodies the ad-
out a photographic survey of China's land resources, monitor its geographical environ-
vantages universities play working across multiple disciplines, actively confronting ma-
ment and conduct scientific mapping research. Such verified new technology, stereo-
jor national strategic needs, and their determination and ability to make an important
scopic mapping method has been applied in China's lunar satellite Change-1 to get the 3-
contribution to the national aerospace industry. It also shows that HIT has become an
D Moon map.
important force in satellite development.
Fig. 3. Illustration of the Shiyan-1 satellite.
Fig. 1. HIT Campuses.
Fig.2. Main Building of RCST.
Fig. 4. Illustration of the Shiyan-3 satellite.
Shiyan-3 Satellite
Research Center of Satellite Technology (RCST) was founded in 1998. Based on
Shiyan-3 was the second satellite developed by RCST during 2006-2008. It was
the micro spacecraft design and new technology application, RCST has become the larg-
the third technology test satellite of China and primarily used in testing new technologies
est small satellite engineering, research and education center among the universities in
of space atmospheric exploration. It was launched into 800km height OOS orbit on No-
China.
vember 5th, 2008. This satellite is 3-axis stabilized and the mass is around 250 kg. More
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than 10 test payloads, including several micro sensors using MEMS technology, had
been performed during its two years life time.
Kuaizhou-1 Satellite
The third satellite, named Kuaizhou-1, is used to monitor natural disasters and
BAUMAN UNIVERSITY YOUTH SPACE CENTRE’S EXPERIENCE
IN DEVELOPMENT OF SCIENTIFIC AND EDUCATIONAL
MICRO- AND NANO-SATELLITE TECHNOLOGIES
Victor Leonov
provide disaster-relief information for its user, the National Remote Sensing Center of
Bauman Moscow State Technical University, Russia 105005 Moscow,
China, a public institution under the Ministry of Science and Technology. The
2-nd Baumanskaya, 5
Kuaizhou-1 satellite was launched from Jiuquan by China's new Kuaizhou small launch
vehicle on 25 September 2013. The orbit altitude of this satellite is 300 km.
Youth Space Center (YSC) of Bauman Moscow State Technical University
(BMSTU) was founded in 1989. One of the key vectors of YSC's work is combining
deep theoretical knowledge students get throughout their studies in BMSTU with an actual ability to implement that knowledge in practical work, both by means of supporting
students' own science projects and involving them into research and development projects on designing and creating promising spacecrafts, carried out by request of ministries and industry. Besides, for the students to acquire experience of public appearances
on various international scientific events, taking part in joint international projects and
working in international teams, YSC actively collaborates with international educational
institutions, research centres and industrial facilities.
During YSC's history of more than 25 years, its collective, which mostly consists
Fig.5. The Kuaizhou-1 image used for monitoring the change of new oil depot.
of under-graduate and post-graduate students, as well as some of the BMSTU's professors and specialists from space industrial facilities engaged in collaboration, has carried
out many research and development projects. Among them are the following technical
projects: «Baumanets» student microsatellite, «Assimilation of the Moon», «Inflatable
rigidizable space constructions», «Hardware and software complex for microsatellite attitude control system modeling», «Space experiments on the ISS», «Development of
payload for small satellites» and many others. Within the framework of creating
«Baumanets» student microsatellite in BMSTU Mission Control Centre and Earth Remote Sensing Data Processing Centre were created.
At present, YSC's team works on the following projects:
1. Creating the «Baumanets-2» scientific and educational remote-sensing satellite.
It is a microsatellite of 85 kilograms of weight, carrying out five more scientific experiments, which was designed for remote sensing. Four of the experiments were completely
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designed and created within the BMSTU, and the fifth one in collaboration with the
THERMAL CONTROL COATINGS BASED ON HOLLOW PARTICLES
University of Montpellier-2 (France). The satellite has been designed and is created in
FOR SMALL SATELLITES
cooperation with NPO «Mashinostroyeniya».
Neshchimenko V.V., Koftun Y.S., Yurina V.Y.
2. Development of the suborbital rocketplane, the main aim of which will be carrying out scientific experiments under conditions of microgravity and vacuum, astro-
Department of Physics, Amur State University, Blagoveshchensk, Russia,
e-mail: [email protected].
nomic researches, surveying atmosphere from 30 to 90 kilometers above the Earth surface, Earth remote sensing, and technological experiments.
One of the most important factors influence on the satellites are average energies
3. Building the «Sail-BMSTU» picosatellite, meant for adjustment of the technol-
charged particles of the Earth's radiation belts and the Solar and Galaxy radiation. The
ogy of deploying two-banded thin-filmed structure by means of centrifugal forces – a
spacecraft materials and elements has reversible and irreversible effects during radiation
prototype of a solar sail, refinement of existing mathematical models of systems with
exposure, it is leading to disruption of the normal functioning of the spacecraft systems.
flexible bonds, as well as for flight qualifying onboard hardware and software of the sat-
Therefore researchers paid attention to improving the radiation stability of materials and
ellite. The satellite is planned to be launched from the Russian segment of the ISS during
equipment of spacecraft.
Coatings based on titanium dioxide and zirconium dioxide pigments are widely
extra vehicular activity.
4. Development of the «Tug-BMSTU» with resistojet. It is created for adjusting
new design and technological solutions used in process of creation of the spacecraft, adjusting new resistojet and technologies of removing space debris from LEO. The satellite
is planned to be launched from the Russian segment of the ISS during extra vehicular
used due to the high radiation stability of the optical properties to impact of the space
charged particles.
We investigated the possibility of creating pigments for thermal control coatings
based on nano- and microspheres. In such structures arising radiation defects will recombine on a large surface of nano- and microparticle. Whereas optical properties this
activity.
powders are similar with the volume material. Thus, we can expect high radiation stability of such structures compared to pigment which is polycrystalline. That can be widely
used in space materials.
A nano-and microspheres were prepared by a chemical method. Hollow particles
of titanium dioxide were obtained from solution titanium: butoxide, ethanol, distilled
water and ammonium bicarbonate. Hollow particles of zirconium dioxide were obtained
from solution: zirconyl chloride octahydrate, distilled water and ammonium hydroxid.
Synthesis was carried out in a steel autoclave teflon coated at temperatures from 70 to
200 0C for 20 hours duration. Thus were obtained hollow particles shown in Fig. 1.
Optical properties and radiation stability of the hollow nano- and microparticles
was carried out relatively of volume microparticles with 99.8% purity, and average particle size 500-1000 nm.
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Fig.1. Micrograph nano-and microspheres, titanium dioxide and zirconium dioxide.
Coating was prepared by mixing 70 wt.% powders and 30 wt.% organic silicon
lacquer. Samples for recording ρλ spectra prepared by coating aluminum disc (Ø=17
mm). The reflective spectra of the samples were measured using a Perkin Elmer Lambda
Fig. 3. Diffuse reflection spectra coatings based on hollow and micro particles
950 spectrophotometer with a scanning rate of 5 nm/s and a wavelength between 250 to
of the zirconium dioxide (A) and titanium dioxide (B) after electrons and protons exposure
2500 nm. The samples were irradiated with protons and electrons under identical condi-
(E = 100 keV, F = 5x10 15 cm-2).
tions: the particle energy was 100 keV, the fluence was 5×1015 cm-2, the flux density
was 1×1012 cm-2s-1, and vacuum was maintained at 2.5×10-4 Pa.
The value of solar absorptance of the samples was calculated in accordance with
ASTM (E490 and E903-00a-96). Established that coatings based on hollow particle values are as=0.094 for ZrO2 and as=0.147 for TiO2, but microparticles has as=0.083 for
ZrO2, as=0.159 for TiO2.
Radiation protons and electrons exposure to coatings based on hollow and microparticles leads to a decrease in the reflectance in the entire spectral region for all
samples (Fig.3.). As follows from the obtained spectra the most radiation stability has
hollow particles coating, which can be evaluate by the change in solar absorption (Δas
=asafter- asbefore): for proton irradiation of ZrO2 microparticles Δas=0.207, but for hollow
particles Δas is 0.078, micro-TiO2 of Δas = 0.197 and hollow-TiO2 of Δas = 0.039; for
electron irradiation Δas = 0.239 and 0.089 for ZrO2, Δas =0.176 and 0.027 for TiO2, respectively for coating based on micro- and hollow particles.
Fig. 2. Diffuse reflectance spectra of coatings based on hollow and micro particles
of the zirconium dioxide (A) and titanium dioxide (B).
From Fig. 2, it is observed that the reflectance spectra of coating based on hollow
particle and volume particles closely similar, but small deviations has in the IR region.
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ASRTU FUTURE SATELLITE: DESIGN AND MISSION
quiring scientific data connected with exploring Earth and space. Second part is educa-
GOALS DISCUSSION
tional goals: giving students practical experience of designing, constructing, testing and
maintenance of the satellite and its systems; training highly qualified specialists for
Alexander Kharlan
Bauman Moscow State Technical University, Russia 105005 Moscow, 2-nd Baumanskaya, 5
space industry; increasing the level of interest among students of schools and universities in space technologies.
Building student microsatellites is of great importance nowadays. Microsatellite
Onboard the «Baumanets-2» satellite it is planned to carry out 5 scientific experi-
technologies are developing quickly today, and it is important for leading scientific
ments, some of which are anticipated to be developed, and hardware used for them to be
communities to get themselves tightly involved in this process. Constructing a microsa-
upgraded and installed onboard future satellites. The Onboard Computer, which was
tellite provides students with real engineering practice, gets them acquainted with the
wholly designed and created by students of Bauman University, is now only an experi-
newest technologies and plays a great role in training of new engineers.
mental piece of onboard hardware, but its capabilities will surely provide an opportunity
In Bauman Moscow State Technical University (BMSTU) such work has been
to use it as a core element of the platform. The «Globalstar» experiment, which provides
carried out for more than ten years now, and the experience the University has acquired
an additional control channel for the satellite, is certainly a promising feature, allowing
up to this moment is to be implemented in new promising projects. We are now to pose
any interested person to establish a connection with a satellite from almost any part of
new problems that have to be solved by means of microsatellite technologies and estab-
the world, so experiments on that will certainly be continued.
lish new ways of finding promising technical solutions.
In addition to the microsatellite itself, other parts of the space complex have been
There are many student microsatellites now being constructed by Russian and for-
created, such as Mission Control Centre and Earth Remote Sensing Data Processing
eign technical universities. The key advantage of «Baumanets» microsatellite platform
Centre. In conjunction with the future ASRTU satellite they may become an indispensa-
developed in BMSTU is its exceptional scientific capabilities. And that’s why it is sug-
ble part of the space complex implemented for performing various tasks from remote
gested to use this platform as a basis in designing the future ASRTU satellite. All com-
sensing to monitoring the sun and beyond that.
ponents of the platform have been properly tested according to all standards of Russian
The process of creating the microsatellite bus has established an effective coop-
spacecraft engineering. The second satellite, «Baumanets-2», based on this platform is
eration between Bauman Moscow State Technical University and both leading facilities
ready now and awaiting launch circa the end of the current year. Being highly qualified
of the space industry and universities abroad. We expect to broaden this cooperation by
engineers and possessing required skills, specialists of Bauman University were able to
suggesting Universities of Russia and China to participate in our work on the satellite
create a satellite, the purpose of which is not just to launch it to the orbit, but also to per-
platform and experiments for joint creation of the future satellite capable of becoming a
form substantial scientific experiments which, if carried out successfully, will serve as a
unique sample and establishing new standards of cooperation.
basis for new engineering solutions capable of being implemented in future microsatellites.
Creating the future ASRTU satellite is actually a complex of problems that are to
be solved by specialists of various profiles. They may be divided into several parts.
Firstly, engineering solutions in designing, constructing, experimental adjustment,
launch and maintenance of the microsatellite, adjustments of the control methods, ac15
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SPACE STATION ACCOMPANYING SATELLITES DESIGN
Zhou Guanquna, Wang Huia, Liu Xiaoa
3. Satellite Orbit Design
Four satellites share one relative orbit on the space station’s orbit plane, which is
Supervisors: Zhang Jingruib, Zhang Yaob
(b School of Aerospace Engineering, Beijing Institute of Technology,
Beijing, 100081, China)
With the rapid development of microelectronics and MEMS technology, a great of
advanced researches about small satellites have been made. Small satellites nowadays
can finish most of the traditional missions flexibly. Meanwhile they can also overcome
traditional satellites’ shortages: high cost, long development cycle and large risk. In re-
Fig. 1. Schematic of Satellite’s
Fig. 2. Schematic of Relative Motion
cent years, the research about accompanying satellites of large spacecraft, especially
Structure.
of Satellites.
space station, has been put into practice.
showed in Fig. 2. The relative orbit approximates an ellipse so that the relative distances
only change in a small range. The gravity of the space station is too small to provide an
1. Satellite Mission
Monitoring is necessary during the construction and maintenance of the space station. The traditional way is to install many sensors in the space station which is complex
and easy to be affected by the space station’s attitude. The accompanying satellites of the
space station can overcome these shortages and finish the mission more flexibly. What’s
more, they can take optional load to finish additional communication or experimental
works. This essay gives a simple design of a space station accompanying satellites sys-
effective dynamic relation between the space station and satellites, so making use of
their relative motion relation is the only way of keeping the accompanying flight.
The following discussion is based on two assumptions: perturbations are ignored
and the orbit of the space station is a circle. One ellipse orbit’s semi-major axis length is
the same as the radius of the space station’s orbit. The period of the satellites in this orbit
equals to the space station’s period, which is the base of building an accompanying orbit.
In Fig. 3, the x-axis is the ellipse orbit’s (dashed line) major axis, and earth is one of its
tem, which involves four satellites in space station’s orbit plane. These four satellites are
focus point. We can see from the figure that the ellipse orbit changes from the «upside»
used to monitoring space station’s condition and providing the alarm of space debris in
to the «downside» of the space station’s orbit periodically. This feature makes the rela-
space station’s orbit plane.
tive motion of the satellite surround the space station.
2. Satellite Structure Design
The accompanying satellites have a Cube-Sat structure which is showed in Fig.1. The
total weight is about 500kg. Monitors and radars are installed at the top and bottom in
order to monitor the space station and space environment nearby. Actuators of the attitude control system consist of flywheels and jets. In addition, one cabin is designed to
carry optional load (extra communication equipment or science experiment facilities).
When the space station and two satellites have special initial relative positions
which is like the mark «1» shows in Fig. 3, two satellites will be in the opposite sides of
the space station all the time. These are the first couple accompanying satellites. The
other couple satellites are arranged according to the same way when the space station
turns 90° (the mark «2» shows). Fig. 2 shows the final relative positions of four satellites
to the space station. Fig.4 gives the simulation result. It appears that the smaller the eccentricity ratio is, the more the orbit is like an ellipse.
Every module works independently to simplify the in-orbit maintenance.
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THE MINIATURIZING OF SMALL SATELLITES BENEFITS
THE MOST FROM MEMS
*
Ridong Zha , Hong Huang, Fulin Luo, Huanpeng Qu
College of Optoelectronic Engineering, Chongqing University,
Chongqing 40044, China
*
Corresponding author: [email protected]
Fig. 3. Schematic of Accompanying Orbit.
Abstract. micro-electro-mechanical system (MEMS) are playing a growing role
on the miniaturizing and integration of small satellites with high performance, which realize an important reduction in the size, mass and power consumption. In this paper, an
overview is given of the range of MEMS application in small satellites. The wireless
networked system consisting of RF MEMS self-powered sensors («Smart Dusk») will be
promising for CubeSats to explore space in the future.
The CubeSat Era (1 kg for 1 U) has truly begun with the launch of the world’s
first cube satellite (namely QuakeSat developed by Stanford University) in 2003. More
and more very small satellites (0~100 kg) are developed recently, the picosatellites (0~1
kg) and nanosatellites (1~10 kg) have become mainstream (Fig. 1) due to their much
Fig. 4. Simulation Results of Different ECC.
smaller mass, power budgets and higher risk tolerance [1].
This essay is a simple discussion of the space station accompanying satellite. Although there is a difference between the practical use and this essay, the discussion still
contributes to the future design of accompanying satellites.
Fig. 1. Number of Attempted Small Satellite Deliveries: 2000-2011 for 1-500 kg
Satellite Class (Global). The inset shows the world’s first CubeSat (QuakeSat) [1].
The very high levels of integration and miniaturization of pico and nanosatellites
with high performance, high reliability, and low-power consumption are only possible
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thanks to MEMS fabrication technologies, which have been proposed for lots of space
when SwissCube is not in the shadow of the earth, one on each face of the satellite (Fig.
applications, i.e., lighter and smaller replacement parts, affordable redundancy to im-
2(d)). The 3-axis Honeywell magnetometer (model HMC1053) was used to obtain the
prove operational reliability. An overview is given as follows of MEMS applications in
local vector of the magnetic field (Fig. 2(e)), and the magnetorquer was used to control
small satellites.
SwissCube’s attitude (Fig. 2(f)). A Cold Gas Micro-Thruster (CGMT) flown on NASA’s
Applications on the Attitude Determination and Control System (ACDS)
MEMS for small satellites are currently focused on their use in the attitude determination: magnetometers, inertial sensors (gyroscopes and accelerometers), and optical
sensors such as sun sensors and star trackers. The attitude control mainly relies on
ST5 mission (Fig. 3(b)) is a good solution to miniaturize the thruster used in attitude
control. Such MEMS propulsion system can produce low thrust from 1uN to at most 1N.
The high performance of ADCS thanks to the highly reliable commercial devices (gyroscopes & magnetometer) and the miniaturizing of key sensors and actuators.
thrusters or magnetorquers.
SwissCube is a CubeSat developed in Switzerland and launched in Step.2009 [2],
which is a good example of the use of MEMS devices on a CubeSat. To take pictures of
the atmospheric airglow (Fig. 2 (a)) with a 50g-telescope (Fig. 2 (b)), MEMS components are used essentially to meet the attitude determination accurate (≤1  ).
Fig. 3. (a) Artist's illustration of the ST5 mission. (b) Illustration of the CGMT device.
(c) View of the X-band transponder. (d) Two cross-link picosatellites (each weighs 245g).
(e) Illustration of major PICOSAT1.0 components for a single spacecraft [3].
Applications on other subsystems
RF Switches and Variable Capacitors: MEMS makes it easier to fabricate very compact low-loss RF switches and capacitors with a large tuning range, which have flown in
space on the OPAL PicoSats (Fig. 3(d)&(e)) in 2000. RF communication to ground of ST5
is through miniature X-band transponder (Fig. 3(c)).
Louvers of thermal control: NASA’s Space Technology (ST5) launched in
Mar.2006 represents NASA's first experiment in the design of a full-service microsatellite constellation, whose science objectives are to measure the effect of solar activity on
Fig. 2. (a) artist’s impression of SwissCube in orbit. (b) The miniature telescope payload
aperture with the baffle. (c) Part of the ADCS board on SwissCube. (d) The MOEMS sun
sensor at the center of each face of SwissCube. (e) 3-axis magnetometer on SwissCube.
(f) A magnetorquers and a PCB. Source: Space Center EPFL 2008.
The MEMS gyroscopes were the ADXRS614 from Analog Device and the
method of mounting is as shown in Fig. 2(c). Six micro-machined Sun sensors are used
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the Earth's magnetosphere (Fig. 3(a)). ST5 uses a polysilicon process, allowing the emittance of the spacecraft to be varied.
Applications on payloads
Optical instrumentation: the NIR-Spec (Near Infrared Spectrometer) on the James
Webb Space Telescope (JWST) used MEMS-based micro-shutters (Fig. 4(a)&(b)).
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Bio and Microfluidics: microfluidics devices are promising in medical or lab-onchip applications, have been flow on GeneSat1 in 2006 to study the development of E.
Coli cells in microgravity as well as in a micro-bioreactor (Fig. 4(c)&(d)&(e)).
A NEW MICROTHRUSTER FOR SMALL SATELLITES
Sun Ying, Xia Guangqing
School of Aeronautics And Astronautics, State Key Laboratory
(c)
(e)
(f)
of Structure Analysis for Industrial Equipment, Dalian University
of Technology, Liaoning, China,
(d)
Small satellites possess the advantages of small volume, low weight, good performance, high reliability, relatively quick manufacture and low cost and so forth, which
presents that they can not only perform the main functions of the traditional large size
satellites, but also accomplish different and high demands with distributed satellites constellation. Therefore, they have wider applications potentiality.
Fig. 4. (a) Artist's rendering of the JWST observatory. (b) CAD layout of the NIRSpec instrument
The formations of small satellites will play an indispensable role in the future
with outer shroud removed. (c) View of the GeneSat-1 nanosatellite. (d) The pressurized payload
utilization of the space. Due to the increasing urgency, more countries tend to develop
volume and optical bench of GeneSat-1. (e) Schematic view of the integrated optical detector system [3]. (f) A depiction of Moballs being released on Mars [5].
In conclusion, pico and nanosatellites are very popular nowadays, owing to much
small satellites in terms of all aspects, where with the development and application of
small satellites, new types of advanced microthrusters are researched and improved for
station keeping along with attitude control and precise pointing.
smaller mass and power budgets, which thanks to MEMS, such technology has been in-
The microhollow cathode discharge (MHCD) is a kind of micro non-equilibrium
creasingly used in satellites even in scientific missions. NASA ever studied wind-driven
gas discharge. MHCD plasma thruster is a new microplasma propulsion system for pro-
wireless networked system of mobile MEMS sensors like «Smart Dust» for Mars explora-
viding a micro-Newton level thrust with high efficiency and low power using microdis-
tion (Fig.4 (f)). It’ll be easier for CubeSats to explore space just releasing lots of such self-
charge plasma. Furthermore, the thrust produced by this kind of propulsion system is
powered RF «Smart Dust» [4].
preliminary expected to be in the range of several tens to several hundreds microNewton and the specific impulse is evaluated on the order of 1000 N·s/kg when using
1. Dominic DePasquale and A.C. Charania, «Nano/ Microsatellite Launch Demand Assessment
2011», SpaceWorks Commercial (2011).
2. H. R. Shea, «MEMS for pico- to micro-satellites», Proc. SPIE, 7208,7208M,1-8(2009).
3. ESA: www.directory.eoportal.org, 10 th Mar. 2014.
4. Ben W. Cook, «SoC Issues for RF Smart Dust», Proc. IEEE, 94(6),1177-1196(2006).
5. NASA Tech Briefs, Jan. 2013.
argon while on the order of 3000 N·s/kg using helium as propellant gas.
The MHCD device is a metal-dielectric-metal sandwich structure. Two 100 μm
thick molybdenum foils, acting as electrodes, are stacked on a 250 μm thick alumina
foil. The schematic structure of a MHCD
plasma thruster has a very simple configuration
and comprises two main parts (the MHCD and
the micro-nozzle) as shown in Fig. 1.
Fig. 1. MHCD Plasma Thruster.
23
24
The experiments on MHCD have revealed some excellent characteristics in terms
NETWORK CODING TECHNIQUES WITHIN
of discharge, gas temperature measurement and electron density measurement. As we
THESATELLITE COMMUNICATIONS.
can know from these experiments, under the same pressure conditions, both the specific
impulse and the thrust increase linearly with increasing discharge current, since gas temperature experiences the same trend with discharge current. On the other hand, under the
Taras Plyushko, Elena Lyakhova, Mikhail Denshchikov, SergeyKuperov
Department of Electronics and Communications, Far Eastern Federal University,
Vladivostok, Russia, e-mail: [email protected].
same current condition, as the gas temperature increased would scale proportionally to
the rise of pressure, the specific impulse and the thrust also see the same trend with pressure.
Benefits of network coding in terms of bandwidth, security and reliability are well
understood for a wide class of networks, but a necessity to achieve similar performance
The MHCD plasma thruster has several advantages, including simple structure,
improvements in satellite communications has appeared not so long ago. A comparative
stable discharge at high pressure, operating in a variety of propellants such as argon, he-
analysis shows thatsome methods of coding are worthy of consideration in the design of
lium or xenon, and the possibility for forming a large array of individual microthrusters
new satellite systems considering thedynamics of the communication network’s devel-
on a single substrate/panel to produce large range thrust. The evaluated specific impulse
opment.
is on the order of 1000 N·s/kg when using argon while on the order of 3000 N·s/kg using
The implement of information coding and modulation of the signal, transmitted
helium and the thrust is in the range about several tens to several hundreds micro-
via satellite, is quite logical in case of improvement the utilization of satellite resources
Newton.
on the physical layer.
Overall, MHCD can efficiently make use of a bit power of small satellite and create a new method to improve the performance of small satellites. In consequence,
MHCD plasma thruster is a promising one which is expected to apply to thrust subsys-
The DVB-S2 standard for video broadcasting, interactive services andother
broadband satellite applications, which is used in all new installations, was designed in
2004. A more efficient noise-free coding is used in DVB-S2: internal code with lowdensity parity-check (Low Density Parity Check, LDPC) and the external Bose –
tem in small satellites properly.
Chaudhuri – Hocquenghem code (Bose-Chaudhuri-Hocquenghem, BCH).
This coding scheme allows channels with the random errors to approach closely to
the Shannon limit. The Shannon limit specifies the signal noise rate (Signal Noise Rate,
SNR) that is required to transmit information through the channel at a predetermined rate
without errors. The probability of an error in a symbol reception depends on various factors (on method of modulation and coding in particular), and not only on SNR. Therefore,
the dependenceof bit error rate (Bit Error Rate, BER) from the SNRis used for different
types of modulation. Furthermore, the enhanced amount of coding coefficients (FEC 1/4,
1/ 3, 2 /5, 1 /2, 3 /5, 2 /3, 3 /4, 4 /5, 5 /6, 8/9 and 9/10) is provided in DVB-S2 at a variety
of different types of modulation techniques (QPSK, 8PSK, 16APSK and 32APSK).
The feature of DVB-S2 lays in the technology of adaptive coding and modulation
(ACM). It allows us to change modulation scheme and coding rate dynamically for each
frame of the forward channeldependingon the signal propagation conditions while main25
26
taining a constant symbol rate. The remote terminal in the ACM mode constantly evalu-
and speed of computer equipment. The relevance of compared LDPC-codes with other
ates the signal quality to determine the optimal mod code. If the central earth station
classes of codes dues to the following advantages of their usage:
(CES) uses a suboptimal mod code or propagation conditions have been changed in the
LDPC codes reach the Shannon limit at a great length of the codeword;
given area,the terminal transmits information about this to CES, and thenmoves to an-
There is no error floor in the properly constructed code;
other mod code. This allowstoprovidedata transferring rate over 60 Mbit/s. This kind of
There are effective algorithms for decoding LDPC codes.
adaptation is also possible for return channels - from VSAT terminals to the CES.
LDPC-codes can be used for TDMA, FDMA, CDMA channels.
Despite the fact that LDPC codes have been almost eliminated from consideration
Anotherphysical level mechanismcan be used to improve the utilization of satel-
over time, there has been an increase in the amount of researches in this area in recent
lite channels significantly. This mechanism involves the combination of forward and re-
years. This is due to the fact that the codes of the low-density parity-check code provide
verse frequency channels. It is patented by Viasat Inc. - Paired Carrier Multiple Access
a high degree of error correction. It was shown that some LDPC- codes can outperform
turbo codes and approach the capacity of a channel with additive white Gaussian noise
(PCMA). Forward and reverse channels operate at different frequencies, according to
this, their frequency resources summarizes.
(AWGN) while increasing length of the codeword. Currently, LDPC-code with exemplary block length of 10 million bits gives the maximum approximation to the Shannon
bound. However, many of the proposed LDPC-codes designs are cyclic or quasi cyclic,
it allows providing not only fast decoding, but also effective coding procedures. Also,
efficient coding procedures have been proposed for non-cyclic LDPC-codes.
LDPC-codes are necessary in data transmission systems which require maximum
transmission rate with limited bandwidth. The main competitor of LDPC-codes for now
Forward and reverse channels are transmitted in the same frequency band using
the technology of combining. This can significantly reduce the satellite resources demand. In this case, the receivers get satellite signals of both forward and reverse channels and should be able to select the desired one at all stations of the network. Performance of suchdevice, mounted on CES, is enough to compensate the forward channel signal in such a wide frequency band.
This technology saves up to 40 % band. The CES must have some margin of En-
are turbo codes which are applied in satellite communication systems, some of the standards of digital television and mobile communication systems of the third generation.
Unlike turbo codes, LDPC-codes are more preferred in the channels with smaller
error probabilities. Transfer channels are also improving with the development of meth-
ergy (SNR) for this frequency division. The required reserve will be 1-2 dB. Thus it can
be used innew networks, which will be provided with such technologies during engineering.
ods for transmitting information, and it gives good prospects for the development of
LDPC-codes.
There is also the legal aspect in using LDPC-codes and turbo codes. The company
named France Telecom and Télédiffusionde France had patented a broad class of turbo
codes, whichlimits their usage and stimulates the development and usage of other encoding methods at the same time. LDPC- codes do not fall under patent restrictions.
There are some objective reasons why LDPC- codes didn’t occupy a leading position in the line of correcting codes until recently. Those are high resource intensiveness
and computational complexity in decoding. But presently LDPC-codes can be considered as one of the most effective codes in connection with the development of the power
27
28
SMALL SATELLITE POWER SUPPLY SYSTEM SOLUTIONS
ergy shortage in space. The successful completion of this problem directly affects on the
lifetime and work capacity of spacecraft.
Alexandr Vorontsov, Master Student,
Vladimir Gravshin, Bachelor Student,
Denis Petrov, Bachelor Student,
Vladimir Glushkov, PhD, Associate professor
Instrumentation Engineering Faculty, Kalashnikov Izhevsk State
Technical University, Izhevsk, Russia,
E-mail: [email protected] , [email protected]
2. The embodiments of power supply and its features
We will compare the embodiments of small satellite power supply system with
major consideration of its mass and performance. Given the current state of space technique, it makes sense to consider two approaches to power supply system:
Direct Energy Transfer (DET) system with Regulated Bus (Fig. 1).
Modular MPPT Bus (Fig. 2).
Abstract. The microsatellite project of Kalashnikov Izhevsk State Technical University with operational name «Kalashnikov Izhevsk State Technical University’s microsatellite» is aimed for design and development of microsatellite with mass up to
55kg. This paper presents variants of the power supply system organization in the context of this project. Due to the project specificity, power supply system with Regulated
Bus turns out to be preferable, but also the opportunity of Solar Cell Modular Maximum
Power Point Tracker (MPPT) Bus application is considered. In addition, a brief assessment of probable supercapacitors application in a spacecraft power supply system is
Fig. 1. DET system
Fig. 2. Modular MPPT Bus.
with Regulated Bus.
given. This paper is the result of the analysis of public available information.
The first approach provides that power is supplied directly onto the bus from the
1. Introduction
solar arrays via blocking diodes. During the sunlight, the bus voltage is regulated to 28 V
Currently, Russian Federal Government has started the support programme, de-
by the SR, which dissipates the excess power of the solar arrays. For period of eclipse
voted to creation and launching of students satellites with low weight. Thereby, Kalash-
the battery is connected to the bus, further, the battery discharges through the regulator
nikov Izhevsk State Technical University started the project of creation of own microsa-
and feeds the payload. It is clear that the power losses in this system are quite significant
tellite with a weight up to 55 kg and founded students construction bureau of space de-
because of the shunt system and battery discharge regulator. In addition, given the dif-
vice-making to involve students in real engineering activity. The intended microsatellite’s application is the Earth Remote Sensing (ERS) and researches of the ionosphere.
The bureau’s aim is to develop modern reliable technique systems for the proper
operation of a small satellite. These systems are as follows: power supply system, telemetry system, stabilization and temperature control systems, etc.
The Equipment and every system of spacecraft needs electric energy. Thereby, the
most important problem is to create the optimal and reliable power supply system with
acceptable power-weight-size characteristics as well as lifetime. This is due to the en-
ferent voltage levels for the different load types, the DC/DC converters may be added to
the circuit, that makes the system much more inefficient. All these factors eventually
lead to increase in weight of solar arrays and the whole power supply system’s cost.
The second approach is based on the fact that the bus voltage is regulated to the
Maximum Power Point (MPP) of current-voltage characteristics of the solar array. When
more power is available from the arrays than is required by the spacecraft, power from
the array is ‘backed-off’ by allowing the maximum power point to be spoiled, wherein
the array voltage drift towards the open circuit voltage.
29
30
Control signals (as shown in Fig.2) are connected between each MPPT unit to
ESTIMATION OF THE POSSIBILITIES
maintain the bus voltage at the desired level. The operation and thermal control of each
OF THE MULTI-SATELLITE GROUP OF «CUBESAT» SATELLITES
module is independent of the other units. Thus, different battery types can be connected
ON THE GROUNDWORK OF BOTH TECHNOLOGY
on to the same bus, meaning that the power supply system can be distributed around the
AND FUNCTION RESTRICTIONS.
spacecraft instead of in a single location.
Chernyshov A. N., Vorobiev A. L., Vassiliev V. S.
Most importantly, the system is very mass and power efficient due to the shunt
Moscow Aviation Institute (National Research University)
system is absent and optimal use of solar arrays energy is present.
Faculty of Aerospace Technology, Special Design Bureau «Iskra»
3. The uses of supercapacitors in satellite power supply system
The use of supercapacitors is justified in conjunction with battery, when there is
the need to get initial brief currents. In this case the battery provides long-term feeding,
and supercapacitors provide high brief current to payload. They also can be used as a redundant power supply, this is the case when possible time of their work as a redundant
power supply between the charge-discharge cycles is quite significant. The full replacement batteries for capacitors is allowed while only in satellites, consuming a quite small
energy (picosatellites, nanosatellites) due to low specific power of supercapacitors (1-10
W/kg), high self-discharge, and almost linear decrease of voltage during discharge. In
the future the supercapacitors improvement is capable to lead to essential spacecraft
mass reduction and its increased reliability and lifetime.
The one of main objectives of modern space technology is the development of
numerous projects of space vehicles of the new generation, the pico-satellites corresponding to the unified international mass standard «CubeSat». This format defines the
main geometric parameters of the segmenting vehicles having the cubic form-factor with
the cube edge dimension equal to 100mm, as well as their combination of 2,3,4… units.
This standard allows one the use for the launch of the CubeSat vehicles of standard
launching technic including the cluster launch. This technology allows reducing significantly the costs of the project because of the reduced costs and low mass of launched
technic.
The pico-satellites are not useful for the orbital injection of large-size equipment,
4. Conclusion
therefore they are excluded from this segment of market of spatial technologies. On the
The comparative analysis of two proposed embodiments has shown that the DET
other hand, one of main modern tendencies is the minimization of dimensions of equip-
system with Regulated Bus is preferable for students microsatellite because of its rela-
ment of all-types; therefore the adequate quantity of equipment can be placed in the
tive simplicity and prevalence in practice, however, the system with Modular MPPT Bus
pico-satellite.
lets reduce the mass of expensive solar arrays as this system leverages the produced en-
Now the following equipment is useful to operate on the CubSat satellites:
ergy, choosing the solar arrays MPP. Moreover, in case of use of MPPT there is no need
a – the equipment for the optical mapping of the ground surface in various spec-
in the shunt system of solar arrays, that is further reducing the cost of the spacecraft and
excluding additional heat emission and power losses in the shunt system elements.
Supercapacitors in the spacecraft power supply system allow significantly ease the
tral regimes;
b – the equipment for the investigation of the properties of the physical and
chemical properties of the top of athmosphere;
battery modes and can fully replace the batteries in satellite with a quite small energy
c – the equipment for the measurement and interaction with magnetic fields;
demand, this fact leads to the significant mass reduction and the increased spacecraft
d – the equipment for the measurement of the physical and chemical parameters
of cosmic-ray particles;
lifetime.
31
32
e – the equipment for biological experiments;
DISTANT RADIO WAVE SOUNDING TO DETECT FORERUNNERS
f – the equipment for various physical and chemical experiments including new
OF EARTHQUAKES
materials forming;
Kosenko Ivan Viktorovich , Lopatko Konstantin Olegovich,
g – the new flight computers,
Romashin Aleksandr Nikolaevich
h – and the equipment for the special communications paths.
Moscow State Technical University of Radioengineering, Electronics
To solve the problems mentioned above the parameters of trajectories for the
and Automation, Moscow, Russia
pico-satellites have to be formed individually; this is one of the main specificities that
e-mail [email protected]
differs the classes of CubSat vehicles.
The most topical now are the following missions and trajectory parameters:
the arbitrary orbits allowing the passing launch of cubsats together with the largesize vehicles are useful with the variants b, d, e, f, g if the mission does not provide any
The end of 20th century and the beginning of 21st century is characterized by
cataclysms becoming more frequent. Earthquakes, sun X-ray flashs, magnetic storms
and a range of other geophysical effects among them takes a special danger for mankind.
supplementary trajectory constraints;
The working out of corresponded system concepts is need for done in good time dis-
the circular orbits of various height are allowed for the variants a, b, c, d, e, f, g, h,
the orbite’s height and inclination are defined by the mission and/or the conditions of the
passing launch;
covering of forerunners of such destructive for mankind situations before their arising.
Their working out is possible on the basis of big scientific technical potential accumulated
for the last decades while a large scale territorially distributed systems were established.
the orbits of space disposal forming specially for this mission are allowed for the
variants b, c, d, f.
We should point out, that many established earlier for state defense tasks systems
lose the significance which they had to the moment of development because of disparity
the orbital constellations with structured disposition of the cluster of space vehi-
separate technical features to modern requirements.
cles operation on the united information space are useful for the variants a, c, g, h.
To solve all the problems mentioned above the volume needed to place both the
equipment and the communications in the satellite have to be provided. Therefore the
forming of the unified hardware-in-the loop simulation systems adopted for the quick
design of all the types of CubSats must be provided. Now most of the systems including
the flight computers can go in one CubSat unit. The second unit must be taken by the
orientation system if it is needed for the mission. The remained volume can be used for
the work load considering the sub-volume needed for the energy system extension (including the folding sun batteries).
In this connection problem of discovering of earthquake forerunners takes special
place.
Therefore the discovering of earthquake forerunners assumes a special world significance. While the field of long term forecasting there have appeared some directions
and methods, the task of discovering of earthquake forerunners is rather acute.
In present work primary attention is paid to usage of global electromagnetic fields
conducted by radiotehcnical systems for earthquake forerunners control. Observations
for electromagnetic fields of different nature are carried out in the seismically active
world regions during many decades. Numerous works were carried out in the sphere of
Thus, for the pico-satellites of the CubSat class the sufficient intrinsic classification can be considered, so that simplifies the design concept: «mission class» + «orbit
type» + «work load properties». The coordination and concretization of these parameters
allows one to form the initial vehicle structure to develop the draft proposal as well as
the draft design.
seismic origin effects choosing in natural electromagnetic fields structure. Ionosphere
descriptions changes were studied before seismic events. But, unfortunately accumulated
experimental material doesn't allow to make definite and reliable conclusions about stable perturbations existence in either Earth cover in epicenter region before earthquakes
since every strong earthquake is unrepeatable and unique [2]. Observations for emana-
33
34
tions excretion, water level change in holes, deformografic observation etc. haven't led to
THE FOUNDSAT PROJECT
results desired as well.
Guohua Kang, Zhou Ye, Xuefen Chen, Ping Shen
In first turn we consider it to be connected with disparity of observed phenomenon spatial scale and used observations methods.
As known just before earthquakes enormous plots of the earth crust are involved.
Department Of Astronautics, NanJing University Of Aeronautics
And Astronautics, Nanjing, China, e-mail: [email protected]
University Background
Different investigators give different zone of expected cataclysm radius estimation but
they differ insignificantly equal near to R = eM, where R – zone of expected earthquake
Microsatellite Engineering and Technology Center (MSTC) of Nanjing University
radius, M – magnitude, characterizing excreted energy of threatening earthquake or ap-
of Aeronautics and Astronautics(NUAA) (Fig. 1) was founded in 2005. We’ve focused on
proximately Richter scale level. For M =7, R~1000. In this case expected zone square
the research of advanced microsatellite platform, key technologies of new concept mi-
will be equal millions of square km. It's evident that existence on such a site a network of
seismic and geophysics observation stations of high density is unreal. Taking into consideration a seismically dangerous regions complicated relief and geological structure there
shouldn't be expected homogeneous data during earthquake expectation process.
crosatellites and their applications for several years. The center has established four labs
including satellite attitude and orbit control lab, satellite telecommunication and control
lab, integrated electronics lab, structure and thermal control lab (Fig. 2). There are advanced facilities, such as the satellite ground control station with an antenna of 4.2 m.
Processing of heterogeneous data large dimension from spatially dispersed devices present time is practically unrealized.
However, on the basis of experimental control abnormal electromagnetic, geochemical, hydro geological effects are practically always observed just before earthquake in expected zone and far not always revealed in epicenter region of expected
earthquake and they are not synchronous in time.
By this reason existing integral effects change electric descriptions of the earth's
Fig. 1. Overview of MSTC.
Fig. 2. The Four Laboratories.
crust, of atmosphere or ionosphere in expected earthquake zone. These changes form
small value, but are revealed on a considerable site.
Tianxun-1(TX-1) is the first microsatellite of NUAA(Fig. 3). It was completely
Two segmented (ground and space) monitoring system for earthquake precursors
self-designed by MSTC and launched successfully on 9 Nov. 2011 in Taiyuan, China.
has been described in the paper. The ground one uses distortion of both long-wave and
The on-orbit mass of TX-1 is 62kg with 6 months designed life. TX-1 has been in orbit
super long wave signals propagating in spherical waveguide formed by the Earth's sur-
for more than 2 years, and acquired more than 400 valuable Earth observation photos by
face and the lower region of the ionosphere. The space system segment is based on the
now (Fig. 3).
distortion control of signals of satellite systems for different purposes and usage of ionosphere radiotomography methods as well.
Introduction of FoundSat Project
FoundSat is a basic prototype of the new serials of NanoSat designed by MSTC
(Fig.5). It is mainly oriented to undergraduates, graduate students as the NanoSat model
for space scientific experiments, demonstration of new MEMS devices and space knowledge education.
35
36
Easy Assembly and Extension Structure
FoundSat series have similar modular design as the building block which can be
manually assembled with a few tools (Fig. 6). The NanoSat structure can be extended
with simple connection parts (Fig. 7). This design is very convenient for the developer to
configure on board devices with fewer constraints.
Fig. 3. TX-1
Fig. 4. Photos
Fig. 5. Overview
on The Vibration Facility.
of Different Areas.
of 1unit.
Momentum Wheel Based on Traveling-Wave Ultrasonic Motor(TRUM)
Momentum wheel is usually used in microsatellite attitude control system.
It can be quickly assembled and easily expanded. Its structure will be manufactured by a 3D printer, while the on-board devices is selected from commercial shelf.
Therefore, the satellite will be marked with ' Private customized' property to satisfy specific needs of different areas of teaching and researching.
FoundSat will carry a new type of wheel using TRUM to overcome problems of traditional wheels (Fig. 9). TRUM is a new concept power device, its basic principle is to
rely on the reverse piezoelectric effect of piezoelectric ceramics to convert electrical energy into mechanical energy to drive the mechanical load. There are no contacts between
Introduction of Basic Unit of FoundSat
A basic unit of FoundSat is a cube of 10cm×10cm×10cm(Fig. 5). Its power will
be supplied by the lithium battery and body-mounted solar array. Its basic attitude con-
the stator and the rotor resulting in frictionless, long life, self-lock free and high speed.
The character of the wheel with TRUM in FoundSat are as follows: Full voltage start
time<50ms; Central RPM: 3000 r/min; Torque>10mNm; Power<0.5W.
trol mode is three-axis stabilized control. And the data processing unit is integrated by a
FPGA core board based on SoPC while telecontrol system and data downlinks sharing
S-band USB system; with the3 month designed life (Fig. 8).
Space Environmental Anomaly Sensor
Nano-satellite is sensitive to space radiation because of its high electronic integration, and space environment anomaly is usually major factor to cause the malfunction of
the satellite. The Compact Environmental Anomaly Sensor(CEASE,Fig,11) in FoundSat
can effectively monitor the threats (including total radiation dose, radiation dose rate,
surface dielectric charging, deep dielectric charging and single event effects )and send
out alarms (Fig. 12).
Fig. 6. A single
Fig. 7. Expended
Structure unit.
Structure.
Fig. 9. TRUM.
Fig. 8. Explode
Fig. 10. Wheel
on Top.
Fig. 12. CEASE
in FoundSat.
View.
37
Fig. 11. CEASE
38
NANO/PICO SATELLITE TECHNOLOGY PROGRESS
IN NANJING UNIVERSITY OF SCIENCE AND TECHNOLOGY
Pico/Nano-satellite technology in a relatively short period of time, including the
mission analysis, project management, quality control, satellite system design, satellite
assembly, integration and testing, launching, ground telemetry and telecommand, etc.
Xiang Zhang, Xiaokang Yu, Yujie Zhou, Haizhen Gao
Nano/Pico Satellite center, Nanjing University
of Science and Technology, 210094
NJUST joins the QB50 project in April, 2012. QB50 is funded via the FP7 programme of the European Commission, with the purposes for multi-point, in-situ, longduration exploration of the lower thermosphere (90-320km), for re-entry research and
Nanjing University of Science and Technology (NJUST) is a multi-disciplinary
for in-orbit demonstration of technologies and miniaturized sensors using an interna-
university incorporating science, engineering, liberal arts, economics, business, man-
tional network of 50 three-unit or double-unit CubeSats. NJUST takes charge of the de-
agement, law and education for coordinated development. It has 16 schools (School of
velopment of one double-unit CubeSat, named by NJUST-1, which will be launched in
Mechanical Engineering, School of Electronic and Optical Engineering, School of Com-
April-June, 2016. The tasks of NJUST-1 are: (1) complete the in-situ exploration of the
puter Science & Technology, School of Automation...) and 26, 000 Students.
lower thermosphere as other CubeSats in the network; (2) demonstrate the technologies
NJUST has been participating in a number of National astronautical projects and
of satellite networking and inter-satellite communication; (3) demonstrate the mi-
the students from different majors have been involved in these projects and show great
cro/nano modules or components developed by NJUST and the satellite system technol-
interests in astronautical research. The Micro/Nano Research Center is established in
ogy. Except for NJUST-1, our center is also developing two other CubeSats. One is a
2011. Now it has students studying in diverse disciplines and majors in NJUST. The mo-
double-unit CubeSat and the other is a three-unit CubeSat, both of which will be deliv-
tivation of the establishment of the Nano/Pico satellite center is to educate the students’
ered at the end of 2015. Our purpose is to provide diverse in-situ application services
abilities in space technology, space experiments, and system engineering via practical
mainly based on the software radio technology, such as navigation, networking, inter-
participation in Nano/Pico satellite projects. The students are able to experience the en-
satellite communication, Automatic Ientification System(AIS), civil aviation/airlines
tire development process of a satellite and gain the knowledge and experiences of
surveillance, etc.
Fig. 1. Layout of NJUST-1 CubeSat.
Fig. 2. Team of NJUST nano/pico satellite center.
39
40
NJUST nano/pico satellite center is still in construction. The development plan of
LASER MODULES FOR IGNITION OF LIQUID ROCKET ENGINES
our center in the coming three years has four aspects: (1) To develop modules or compo-
Aleksandr Savostyanov
nents dedicated to micro/nano/pico satellites and promote the industrialization of these
Student Design and Engineering department, National University of Science and
products, such as the MEMS based miniaturized sensors and executive components, em-
Technology «MISIS», Moscow, Russia, e-mail: [email protected]
bedded system based on-board computer and attitude control computer, communication
transceiver, miniaturized power unit, micro-propel system and inter-satellite ranging and
communication, etc. (2) To construct a set of laboratories or dedicate rooms ensuring the
satellite development, such as the assembly and testing rooms, the data synthesis laboratory, attitude determination and control (ATC) laboratory, ground station and task control center, CubeSat technology laboratory and five other laboratories oriented to astronautical technology. (3) To develop software for satellite design that is capable of combining the multi-discipline optimization technology and the digital simulation. (4)To establish the standards for the micro/nano satellite development and the standards for
Our main target: to create and promote to the international market line of laser
systems and ignition modules for different types of engines. At the first stage – for a
segment of liquid rocket engines (LRE).
Interest of rocket producers lays in the sphere of propulsion systems for laser
technology due to the fact that the method of ignition of rocket fuel in the combustion
chamber with subsequent spread and flame stabilization is one of the important objectives in the design of all types of missiles. Furthermore, currently to reduce the cost of
rocket launching, as a basic condition for creating a new space propulsion, is a requirement of multiple use - several switching possibilities in flight or on-orbit operation. Cer-
ground environmental tests, and to determine the quality certification system for the mi-
tainly, the inclusion of multiple rocket engine has long existed , such as chemical igni-
cro/nano satellite development. (5) to form a matured and stable group for micro/nano
tion, but all available technologies , including chemical , already outdated. In addition,
satellite development and to accumulate experiences in each aspect of the satellite de-
such systems are very heavy, complicated, inefficient and dangerous. Engine manufac-
velopment, such as testing, assembly, telecommunication, attitude control and the appli-
turers are awaiting a technological breakthrough that can solve all the above problems.
cation aspects, such as the satellite image processing, ecology growth demonstration.
And this breakthrough has arrived. Technological innovation, such as laser ignition system for rocket engine opens several important features. The critical issues affecting the
introduction of this system – the lack of specialized laser modules providing ignition
which can withstand significant vibration, shock, thermal, thermal cycling load (at cryogenic temperatures) at a reasonable price. Progress and development of laser technology
allowed us to create laser ignition system, which in weight and size and power consumption characteristics meet the requirements in the aerospace industry .
The novelty of the solutions are to use unique diode lasers based on photonic crystals that create high directivity single-mode radiation when a large amount of the output
aperture; adapting existing solid-state lasers to the conditions of use on real rocket engine, in particular: the selection of optimal operating conditions , the development of optical and electronic software interfaces for the system under extreme temperature
changes, vacuum, high vibrations;to use the technology of microchip lasers , which allows to decrease the thermal stress induced birefringence and to improve the output
characteristics of the laser.
41
42
Set of proposed innovative approaches will create small systems and modules of
QB50 PROJECT – WHAT CAN WE LEARN FROM IT
reliable single and multi-single ignition of rocket engines that reduce the manufacturing
Bai Bo
costs of finite systems in more than 10 times.
Laser modules are designed for using in laser ignition oxygen-kerosene and oxygen-hydrogen rocket engines of large dimension, as well as boosters (RD-107, 108,
Shaanxi Engineering Laboratory for Microsatellites, Northwestern Polytechnical University, Xi’an, China, e-mail: [email protected]
He Wei
0146, 0124, NC-33).
The most realistic scenario is implementing scope laser ignition to Russian rocket
Shaanxi Engineering Laboratory for Microsatellites, Northwestern Polytechnical Uni-
engines - the engines of the 1-st and 2-nd stage of the launch of the «Soyuz» developed
versity, Xi’an, China, e-mail: [email protected]
by NPO «Energomash» , as well as the oxygen-hydrogen engine type RD0146 devel-
Hu Zhi-qiang
oped by «KBHA». Implementation of LIA engines RN type «Soyuz» will eliminate ar-
chaic pyrotechnic system tripod type. However, the laser provides the ignition weight
advantages compared with the developed part of OS chemical ignition system at 100 –
Yang Zhong-guang
150 kg. Implementation ofLIA on RD0146 type engines , in turn, will abandon ignition
system, which has its own delivery system , including valves and piping .
Reducing the weight of the rocket engine upper stage rocket will allow as much as
Abstract. The QB50 project is jointly put forward by Von Karmon Institute of
we can to increase the payload. In the direct laser ignition combustion chamber not only
eliminates the need for all electronic components necessary for spark ignition, but also
eliminates the need to use in the ignition device and into the individual channels respectively supplying the components in the igniter.
It is worth noting that not long ago launched rocket « Antares» using a modified
version of the Russian rocket engine NK-33 . Chance to resume production of this type
of engine increases. It is very good news for our team, because the new engine modifica-
Technology, TU Delft, Surrey Space Center, and Space Center EPFL, Leibniz-Instituts
für Atmosphärenphysik, Stanford University and Shaanxi Engineering Laboratoryfor
Microsatellites (SELM), etc. It is a network with 50 CubeSats that will be used for the
multi-point, online, long-duration measurements in the lower thermosphere. The 50
CubeSats carry a set of standardized sensors for atmospheric research. Each of the QB50
CubeSat will consist of two parts, with one part (the «functional» unit) providing the
usual satellite functions (including attitude determination and control, uplink and
tion is supposed to use 5 laser modules
There are a lot of RnD groups whole over the world whichworks in the sphere of de-
downlink telecommunications, power subsystem, on-board data handling, etc.) and the
velopment of laser-ignition for LRE (although the first tests in large combustion chambers
other part (the «Science» unit) accommodating a set of standardized sensors for lower
was in Russia). Registered more than 600 patents on this topic for other engines. Moreover,
thermosphere research.
about one-third of these patents belong to Bosch.
At the moment, we have implemented all our 1-st stage plans: we designedand
developed several laser modules and conducted successful tests. Now we aredevelopingLIA for large chambers and tor tandem of rocket cells. A conceptual design of the
new «Soyuz», modified fot new spaceport «Vostochniy», has laser ignition.
43
1. Introduction
QB50 project is an international cooperation space research project funded by EU
and many universities are interested in the project and have taken part in. The main purpose of the project is carrying out some innovative experiments, education and increasing cooperation between different counties. In fact, besides the thermosphere detecting,
44
there are some other very interesting and creative experiments, which are progressing
electronics [2-4]. But not all the CubeSats are 1U, they can be enlarged into 2U
smoothly in the project, such as two CubeSat formation flying, re-entry experiment, test-
(20×10×10cm), 3U (30×10×10cm) even 6U (30×20×10cm).
ing of satellite link quality, solar sail experiment, etc. The final launch of the fifty CubeSats is arranged in the year of 2015. Among them, some teams’ satellites will be the first
CubeSat of their country. Hundreds of students who take part in are from over thirty
countries and will gain precious space research experience from QB50 project. Now
over 60 CubeSat teams from over thirty countries in Africa, Asia, Australia, Europe,
North America and South America has joined the QB50.
3. What Can We Learn From It
If we, Astru, want to launch a satellite, first, we should give an objective of the
satellite. That is what the function of the satellite. We can validate some new technology
on the satellite. Second, the satellite can be made in module, which will benefit the participation of all the member of Astru. Each member can give their best capability for the
satellite.
According to the plan, all 50 CubeSats will be launched together on a single launch
vehicle into a circular orbit at 320 km altitude, with an inclination of 79°. Due to atmospheric drag, the orbits of the CubeSats will get progressively lower, perhaps down to 90
km. Thus, lower layers of the thermosphere will be explored without the need for onboard propulsion. The mission lifetime of the whole CubeSats system is estimated to be
about three months.
1. Gill E, Sundaramoorthy P, Bouwmeester J, Zandbergen B, Reinhard R. Formation flying
within a constellation of nano-satellites: The QB50 mission. Acta Astronautica 2013; 82-110.
2. Ilyas D. Orbital Propagation and Formation Flying of CubeSats within QB50 Constellation
[Master's Thesis]: University of Liège; 2011.
3. Woellert K, Ehrenfreund P, Ricco AJ, Hertzfeld H. Cubesats: Cost-effective science and technology platforms for emerging and developing nations. Advances in Space Research 2011: 663-84.
4. Selva D, Krejci D. A survey and assessment of the capabilities of Cubesats for Earth observation. Acta Astronautica. 2012: 50-68.
2. CUBESAT
CubeSat is a new kind of nano-satellites for space research. Professor Jordi PuigSuari in California Polytechnic State University (Cal Poly) and Bob Twiggs in Stanford
University gave great contributions to the development of CubeSat.
Fig. 1. Aoxiang-1 CubeSat of NPU.
The standard size of CubeSat is 10×10×10cm [1], having a mass of no more than
1.33 kilograms, and typically using commercial off-the-shelf (COTS) components for its
45
46
The proposed electronic medical sensors system is an example of the ideology of
ELECTRONIC SYSTEM OF MEDICAL SENSORS
Victoria I. Demidova, Alexander A. Kopylov, Vladimir K. Makukha,
Konstantin S. Morozov
Electronic Devices Department, Novosibirsk State Technical University,
the Internet of Things (IoT). The Internet of things is the connection of end-users devices
by the Internet. All devices may be controlled through the Internet, they can communicate with each other.
From the doctor’s point of view the most informative kind of diagnostics are elec-
[email protected]
trocardiography, blood pressure monitoring and pulse oximetry. But patient often reThe telemedicine systems are intensively developed now. Its allow monitoring the
patient health. Typically, an electronic device contains a specific set of medical sensors
quires other observations. This paper presents some types of medical sensors to monitor
the human body state.
and transmits the information to doctor by GPRS or by a phone.
In this paper development of an electronic system consisting of individual medical
modules sensors (cardiograph, tonometer, pulse oximeter, capnograph, etc.) with stan-
The module of blood pressure measurement is tonometer. It is one of the sensors
in the considered system. A blood pressure is the pressure of blood on the walls of arteries.
dardized wireless interface and hub is presented. Hub must receive information from
Arterial blood pressure is constantly changing throughout the day, so it is impor-
medical sensor’s modules via radio and send it to the cloud storage. Hub can send data to
tant to record changes in dynamic. Developed module measures the pressure using the
cloud via GPRS when working offline and send date to the Internet when connected with
Korotkov`s method. Korotkov`s method provides the most accurate measurement, a high
the computer. The doctor can view the results of observation during communication with
resistance to the movement of hands and other external factors during the measurement,
the computer in real-time.
as compared to other non-invasive methods.
The offered monitoring system, consisting of a set of modules and a hub, is more
All presently used devices for the blood pressure monitoring are composed of a
flexible than widely used monitoring systems. Flexibility of this electronic monitoring
cuff and a single processing block, displaying and storing measurement results. A cuff
system is based on equipping with different number of sensors required for exactly this
and block are interconnected by a thin hose. But use sensor in real-life is imposes some
type of observation. All embedded devices do not need to have a display, this leads to
additional requirements to the module. Functionally developed module consists of a cuff,
downsizing. Modular system monitoring can be competitive in the market of a home and
pump for pumping air into the cuff, a pressure sensor and SoC with microcontroller and
telemedicine's monitoring system, and as well as for stationary applications.
transceiver for controlling and processing signals, received from the pressure sensor. For
The modular system can operate in two modes:
ease of use of the developed module, the electronic part and the pump are located di-
1) Real-life. Person, wearing the modules themselves, can go about their business,
rectly on the cuff, but it easily fits under patient’s clothing.
while modules will automatically to capture and transmit all the necessary information to
The second module is the pulse oximeter module.
a cloud storage;
Pulse oximeters monitor the oxygen saturation and heart rate of the wearer nonin-
2) Observation in hospital. A patient can be in the supine position or walk around
the ward.
vasively. Advanced units are able to display the pulsatile nature of the arterial blood vessels. The operation principle is based on the measurement of the transmittance of differ-
The implementation of this project became possible due to advances in microelectronics, enabling the creation of front-end medical sensor's tiny chip as well as the rapid
ent wavelengths radiation through the tissue in which the blood circulates. Therefore,
optoelectronic assembly is an integral part of the pulse oximeter.
development of wireless information and communication technologies.
47
48
Hemoglobin is the main oxygen carrier. It differently absorbs electromagnetic ra-
The single-channel dual-beam IR spectrometer is used as a CO2 concentration
diation of different wavelengths. The intensity of radiation of absorption varies depend-
sensor. The heterostructure LED is used as a radiation source, and a photodiodes – as the
ing on oxygen content in hemoglobin. These types hemoglobin are called oxyhemoglo-
receiver. This results in a small size and low cost. The development of such electronic
bin (oxygen-rich) and deoxyhemoglobin (oxygen-poor). The greatest difference in ab-
medical sensor system, created in the form of separate modules with standardized wire-
sorption manifested in the red and near infrared region of the spectrum.
less interface, will produce a configurable set of universal different sensors. There are
Optoelectronic assembly is based on two light-emitting diodes (LED) and photo-
other sensors at the department of electronic devices in Novosibirsk State Technical
diode. First LED emits in the red wavelength range (typically 660 nm), second emits in
University has also developed besides presented. The phonoentoroscope and a cardio-
the infrared wavelength range (905 nm, 940 nm and others). The photodiode has a wide
graph are among them, which can be built into the electronic system to expand its diag-
range of spectral sensitivity.
nostic capabilities.
The optoelectronic assembly works by transmissive method and is located on the
earlobe. It connects to the microchip's integrated analog front-end AFE4400, which is
connected to the microcontroller EFM32TG840F32. Microchip AFE4400 controls by
switch of LEDs and reads data from the photodiode for the red and infrared radiation.
Oxyhemoglobin and deoxyhemoglobin concentrations are calculated by Beer's law
based on these data. Oxygen saturation can be calculated knowing these concentrations.
Transmission coefficients at wavelengths of 660 nm, 905 nm and 940 nm for medium-sized earlobe by Beer's law were calculated. The calculation was performed with
taking into account absorption and scattering by tissues, as well as reflections from the
skin. Through this calculation, it was found that the minimum direct LED current is no
more than 1 mA. The calculation was made for LEDs DLED-660/905-LLS-2 (DLED660/940-LLS-3) and photodiode PIN-8.0-LLS.
Not only the cardiovascular system is an informative source of the human body
status, but the exhaled air too. Capnometry in medicine — it is the measurement of the
carbon dioxide concentration in exhaled air. Capnometer is needed for lungs ventilation
in reanimation and anesthesia. Capnometer is rarely used as a diagnostic tool but experts
find it extremely helpful.
The measuring principle is based on the ability of carbon dioxide molecules absorb radiation at certain wavelengths: 2.7, 4.2 and 15 microns. Infrared radiation (4.2
microns wavelength) is used in the target sensor, because of smallest absorption of the
molecules of water, carbon monoxide and others which can be in the air at this wavelength.
49
50
GENERAL AUTOMATIC TEST SYSTEM FOR AVIATION
APPLIED IN CHINA SOUTHERN AIRLINE
Huang Jianhuang, Chen Shule, Xu Xiangmin
School of Electronic and Information Engineering, South China University
of Technology, Xu Xiangmin, China, e-mail: [email protected].
About GATS
GATS is designed to free manual labor, at the same time making work more efficient and accurate. Compared with the traditional test system that only for a specific
Fig.2. Hardware Connection.
electronic equipment, GATS is helpful to prevent duplicate procurement of instruments.
Measuring instruments as follows:
It's easy to maintain and upgrade instruments.
 Spectrum Analyzer
 Oscilloscope
 Digital Multimeter (DMM)
 GPS Signal Generator
 Communication Tester
 GPS Signal Generator
UUT as follows:
Major Structures of GATS
General Automatic Test System is made up of two main sections, the hardware
and the software. Through cooperation between hardware and software, the test result
will be displayed on the industrial control computer's screen.






Multimode Receiver(MMR)
Antenna Pedestal
Weather Radar
ATC Transponder
VHF Transceiver
Radio Altimeter
Fig. 1. Structure Diagram of GATS.
Measuring instruments and UUT(Unit Under Test) are two of the most critical
modules in hardware.
Fig. 3. Software Construction.
System Platform is the core of the software part, and the instrument operating libraries are the bridge between different instruments and the system platform.
51
52
How to Use GATS
VIDEO TRANSMISSION SYSTEM FOR SMALL SATELLITES
To achieve the ability of testing a new UUT, there are six steps development
Shanwen Liu, Hao Wang, Ye Li, Yunzhuang Zheng, Changyin Dong
process to follow:
School of Transportation, Southeast University, Nanjing, China,
1. Collect test requirements
E-mail: [email protected]
2. Determine required instrument
3. Compiler driver of instrument(DLL or FDL)
4. Make Test Unit Adapter
Acknowledgment
This work is supported by the National Basic Research Program of China (Project
5. Write TPS
No. 51008074) and National Undergraduate Innovation Training Program (Project No.
6. Run TPS and Debug UUT
1210286077).
After development, the only need to do is to hook up UUT and run TPS to autoAbstract. We developed an image-processing software, which can process im-
matically check the UUT status.
ages shot by satellites. We use the model aircraft equipped with a video transmission
system to test this software.
1. The introduction to the radio-controlled model aircraft
The model aircraft is equipped with flight control system, HD camera, and wireless video transmission system (See Fig. 1). A ground station is needed for communicating with the model aircraft. Then flight commands can be transmitted to the aircraft from
the ground station, and in turn, the real time flight conditions of the aircraft are sent back
Fig. 4. GATS Platform UI & Measuring Instruments & Unit Under Test.
to the ground station.
Model aircraft
HD camera
Wireless video
transmission system
Fig. 1. Model aircraft and wireless video transmission system.
The model aircraft takes off with the aid of people, reaches to the target area under
the guide of GPS and flight control system. The ground station can monitor the flight
conditions and change the flight commands through wireless video transmission system.
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54
The HD camera will alter its direction accordingly. The real-time video will be stored
THE CONCEPT OF THE FIRST STUDENT SMALL SATELLITE
and transmitted to the ground station (See Fig. 2).
OF THE SOUTH URAL STATE UNIVERSITY
Pavel Belochkina, Kseniya Morunovaa, Alexey Kochengina, Igor Shulevb
a
Faculty of Computer Technologies, Control and Radio Electronics, South
Ural State University, Chelyabinsk, Russia, e-mail: [email protected].
b
Fig. 2. Picture from real-time video transmitted to the ground station.
2. Software
Aerospace Faculty, South Ural State University, Chelyabinsk, Russia,
e-mail: [email protected].
Launching of a space microsatellite is a complex and costly event, that is why
The software extracts the frame in a certain time span from the video. Frames (images) will
be stored. Here, we choose one image as an instance: First, we zoom in on the image in order to be
more precise; second we set the standard coordinates of the road in the image; finally, the coordinates of certain points (such as rearview mirror) of vehicles in each image can be obtained by click-
finding ways that can facilitate cheaper launch is an important task for today. Achievements of the last 10 years in the field of microelectronics and microelectromechanics allow us to create micro-spacecraft which are able to compete with large satellites to fulfill
a number of target function.
ing those points (See Fig. 3). Each image will be analyzed in this way.
The presented concept of the small satellite development includes both calculation
and elaboration of the basic life support systems of the microsatellite, and a review of
launch technology for the small satellite in near-Earth space.
Modern micro-spacecraft is equipped with a variety of automatic on-board systems such as control system, orientation and stabilization, thermal control system, power
supply system, on-board radio, propulsion system. The collaboration of these on-board
(a) Choose one image
(b) Zoom in
Fig. 3. Software running process.
Finally, it is convenient to draw the trajectories of vehicles by using the data of
systems depends on modes of operation and schemes of functioning.
The efficiency of the small spacecraft is determined by the criteria of reliability,
resiliency and survivability. And for non-repairable onboard systems characteristics of
fault withstandability and survivability are provided by reliability.
each image (See Fig. 4).
Thus, ensuring the reliability of a spacecraft, and in particular those of its nonrepairable on board systems as board control system and power supply system is the actual problem. Therefore, one of the aim of this research - is to study the reliability of the
small spacecraft, taking into account possible failures of onboard systems. The subject of
this study are the onboard systems of the small satellite.
Fig. 4. Trajectories of vehicles.
The problem of ensuring the reliability of the small spacecraft, in this case, is
solved by structural redundancy under some restrictions due to the functioning of the
small spacecraft in the absence of skilled care access.
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56
In the early stages of reliability analysis of the small spacecraft the greatest atten-
Magnetometers;
tion is paid to the onboard control and power system as the most important life support
Satellite navigation equipment.
systems of the small satellite, in particular, different options of structural redundancy are
Gyroscopic sensors are intended for determination of angular position and angular
examined and compares, as a way to improve the reliability of the small spacecraft.
velocity of the small spacecraft in space.
The designing of orientation, stabilization and navigation system which is intended for controlling the angular position and motion parameters measuring of the
Sun sensors are intended for determination of the direction to the center of the Sun
in the spacecraft coordinate system.
small spacecraft also carries the difficulties associated with the algorithm of orientation,
which affects accuracy orientation.
Magnetometers are intended for determination of the orientation on the magnetic
field of the Earth.
The main objectives of the orientation, stabilization and navigation system are:
Damping of angular velocities (quieting) of the small spacecraft after its separation from the launch vehicle;
Satellite navigation apparatus is designed to determine position and velocity vectors of the small spacecraft that are bounded to the system time from the signals of
navigation GLONASS / GPS real-time and for generating time reference signals.
Formation of the reference frame and maintaining orientation of the small spacecraft in relation to it.
The calculator comprises a navigation and orientation algorithms. Navigation algorithm is essential part for producing the position coordinates and velocities of the
Calculation and prediction of navigation parameters;
small spacecraft and the orientation algorithm is essential for the solving of orientation
Implementation of program turns;
task. Orientation algorithm can be realized with using of a variety of kinematic parame-
Aggregation with satellite navigation.
ters, such as the Euler-Krylov's angles, direction cosines, Cayley-Klein's parameters, etc.
For the solving of the problem of determining the orientation of the small space-
The choice of kinematic parameters determined by the specifics of a navigation tasks.
craft, the information about its initial position and instantaneous velocity is necessary.
Orientation algorithm is an important block of orientation system, as it determines
Traditional problem solving of orientation and navigation of the small spacecraft is
the accuracy of the production of orientation parameters for the small spacecraft. In con-
based on a combination of inertial radio navigation equipment and satellite measure-
nection with this orientation algorithm of the small spacecraft was simulated, including
ments. Therefore, the objective of navigation and orientation needs to be considered as
Euler- Krylov's equations in Matlab and Mathcad. During the simulation the influence of
an integrated whole.
the differentiation operator on the accuracy of the recovery orientation angles was ana-
For the designing of orientation, stabilization and navigation system of the small
spacecraft the following modules are essential:
lyzed. Moreover, a numerical estimate of modeling errors under such using of direct
numerical differentiation was obtained. Results of simulation are verified no error in
Measurement module;
modeling of orientation algorithm in the case of using symbolic differentiation proce-
Calculator;
dure.
The effector.
Measuring module includes sensors of translational and angular motion of the
small spacecraft. The following sensors are most widely used:
Gyroscopic sensors;
Solar sensors;
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58
LINEAR ELECTRIC MOTORS FOR ELECTROMECHANICAL
INSTALLATIONS: CONSTRUCTIONS, ENGINEERING CALCULATIONS
AND LINGUISTIC DESCRIPTION
V. Tiunov, S. Chikarenko
Department of Electrical Engineering and Electro-mechanics,
Perm National Research Polytechnic University, the city of Perm, Russia
E. mail: [email protected], [email protected], [email protected]
of dictionaries containing the information needed for translation and interpretation of
texts related to Electro-mechanics and its unconventional constructions.
To solve this problem, has been tasked to create a custom thesaurus and computer
interactive English-Russian Dictionary of Electro-mechanical terms, corresponding to
the level of modern technical lexicography. In this regard, the PNRPU Department of
Electrical Engineering and Electro-mechanics has composed interactive English-Russian
electronic thesaurus for specialists with large enough volume. At the moment, the
amount of this thesaurus is more than six thousand linguistic units (words, the most
For more than 40 years the Department of Electrical Engineering and Electro-
common expressions, stable combinations, etc.).
mechanics of the PNRPU has been engaged in research and development of unconven-
At the moment a test version of electronic dictionary is already created. It takes a
tional electric machines and drives, in particular in induction machines with the open
little over two megabytes of memory only, which is much smaller than the size of the
magnetic circuit.
average electronic dictionaries.
There were created linear flat, tubular, front, saddle, segment, disk and arch-stator
motors for devices of high technologies and transport systems in different branches of
industry and for other fields. Some of the motors developed have been successfully
tested by the customers and introduced into production manufacture with unique applications.
The structure of software allows adding to the existing dictionaries the new dictionaries, so there is a possibility of creating a single multi-lingual base of electro technical terms in the same frame, including Chinese language, which should be the object of
Russian-Chinese profitable cooperation.
The practical structures of some examples of induction machines with open mag-
Great attention is paid to the Linear Induction Motors (LIM) applied in systems
netic circuit, created in the PNRPU, are shown on fig. 1-5.
of traveling or alternating movement, testing installations, and also for the gearless devices with rotary motion of an operating body.
It is well known that projecting of LIM for such systems and devices is extremely
complicated as it is conditioned by the influence of edge effects appearing in the LIM
and also by the great variety of motors constructive executions.
Experimental research and computer calculations showed that the theoretical methods designed in the PNRPU provide acceptable calculations accuracy in engineering practice. Traction of the developed flat and tubular LIM is 0.01-5 kN or more and the speed of
motion of operating bodies is equal to 0.2-4 m/s or much higher. The developed motors and
their new theory might have a very wide application and a highly innovative approach to the
Fig .1.
future engineering projects, including possible application in the space systems.
The LIMs have unconventional constructions which are increasingly used in the
recent years. So there is a need of international communications for accelerating their
development. The linguistic problem is that at the moment there are very small amount
59
60
CENTER FOR COORDINATION AND CONTROL
OF SMALL SATELLITES OF UNIVERSITY ITMO.
CONCEPT OF CREATION
Igor Kinzhagulov, Alena Makarova, Anna Malevannaia, Maksim Shuhayeu
Department of Measument Technology and Computing Tomography, St.Petersburg
National Research University of Information Technology, Mechanics and Optics,
St.Petersburg, Russia, e-mail: [email protected]; [email protected];
[email protected]; [email protected]
Fig. 2.
The report presents the concept of creation of the Center for coordination and control (CFCC) of small satellites (SS) implemented by the cooperation of St. Petersburg
National Research University of Information Technologies, Mechanics and Optics
(ITMO) and leading companies in the Federal Space Agency (Fig. 1).
Fig. 3.
Fig. 4.
Fig. 5.
Fig. 1. the concept of creation of the CFCC of SS.
The main purpose of the CFCC of SS is the formation of new competencies in the
field of space information and communication technologies of collection, storage, processing and provision of information, obtained by means of small satellites. The formation of new competencies is possible due to the development and implementation of in-
61
62
novative educational programs implemented by the University ITMO in cooperation
space complex of controlling. Transfer of target information is carried out with a
with ASTRU and enterprises of Roskosmos.
ground-based space complex of reception and information processing.
The priority areas of the Center are implementation of educational space informa-
The basis of making the ground-based space center of information and controlling
tion and communication technologies and performance of research and development
systems of different purposes includes the possibility of testing critical technologies, in
(R&D).
particular:
The execution of research and development is aimed at the solution of following
problems:
the design and manufacturing technologies of intellectual energy supply systems
for SS;
the development of new constructional and technological decisions and design of
perspective space infocommunication and telecommunication means;
the development of technologies of application of orbital systems of SS;
the solution of problems of modern information and navigation support of space
means;
the technology of designing of space radioelectronic systems;
the technologies of designing and test of optical-electronic monitoring systems.
The examples of onboard control and measuring, optical-electronic and SS target
equipment and bench equipment on experimental working off of onboard systems of SS
(an onboard optical-electronic complex of remote sensing of Earth; the bench tests of SS
the development of technologies for the creation of components, assemblies and
products of SS;
solar batteries), developed by the University ITMO are given.
The perspective areas of researches are designated. Making of space system of
the creation of a regional interuniversity ground-based complex of SS controlling.
The technologies of teaching the students methods of SS controlling, SS information receiving and its further processing and etc. can be implemented by the use of the
CFCC of SS equipment.
monitoring for solving tasks of emergency services is one of the researching areas.
Making of space system of monitoring for solving tasks of emergency services
will allow to carry out following tasks:
full-scale development of the technologies of remote sensing of Earth;
Structurally the CFCC of SS includes:
testing of receiving, processing and transmission of the target information;
the group of experimental development of space technologies on the basis of SS;
computer appliance complex development for the use of technologies of Earth
the group of situational modeling and laboratory testing of ground-based and onboard systems of SS;
remote sensing on the basis;
the development of GIS-technologies (digital maps, digital three-dimensional
the group of space information and controlling complexes, telecommunication
complexes;
space model).
In conclusion, the main advantages of CFCC of SS creation are:
ground-based space complex of controlling;
ground-based complex for obtaining and processing the information.
Construction options of ground-based space complex of controlling are offered.
The complex can be created by the use of existing complexes (SS «Mozhaets-4»,
increase of mutual integration of the international organizations, developers of
systems and the organizations for orbit insertion and controlling of SS;
coordination of services, departments and institutions;
development of international cooperation in the framework of a single SS.
«Baumanets-2», etc.) or perspective SS, developed by the University ITMO employees.
The coordination of movement trajectory and monitoring of the position of SS relative to
ground-based observations and other space objects is performed using satellite radionavigation systems. The exchange of telemetric data is made with ground-based
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64
DEVELOPMENT OF REPRESENTATION METHODS
One of the most common methods to implement this approach is the aggregate-
FOR FUNCTIONAL MODELS
modular design of robots. This method is based on the universal interfaces for the infor-
OF AGGREGATE-MODULAR ROBOTS
mation and the mechanical interactions between components of robot. It gives us the opportunity to construct a specialized robot on the base of limited number of standardized
Kalugin N.V., Muliukha V.A.
Telematics Department, St. Petersburg State Polytechnical University,
Saint-Petersburg, Russia
components. Such construction meets the requirements of the current task in the best
possible way, so this specific solution has minimal redundancy.
The main purpose of our work is to research and develop an algorithm for auto-
The creation of an autonomous robot base on the Moon surface is the first step to
matic construction of the optimal configuration for the robot from the set of standardized
verify the technology of Human Exploration of the Moon and other celestial bodies. At
modules to implement a task. It is assumed that such standardized modules have uniform
the moment researches that are focused at the Lunar exploration with robots’ help, are
mechanical and informational interfaces. The main objectives of our work are:
included in the space programs of many countries, including USA, China and Russia.
1. Classification of robots and their modules;
For example, the well-known Chinese Lunar Exploration Program incorporates different
2. Development of a model of aggregate-modular robot;
types of robots: lunar orbiters, landers, rovers and sample return spacecraft.
3. Researching the limits for the robot model, which are based on the
According to the regulatory documents of Russian Space Agency, the main component of the robotic lunar base would be a group of robots, which would be capable to
solve all kind of problems arising during the Moon exploration, namely: manipulation
with objects, transportation of cargo, installation and maintenance of different facilities,
construction and installation works, mining, etc.
requirements for the optimal realization of the task;
4. Development of method and algorithm for automatic construction of the
optimal configured robot.
At the first phase of the research standardized robotics modules have been classified. Following groups have been identified:
There are two main approaches to form such group of robots:
handling systems and control devices;
1. Few multifunctional, complicated for manufacture and maintains robots, each
manipulators;
transport platforms and movement systems for mobile robots;
of them performs a wide range of tasks;
2. Lots of different robots that are easy to manufacture and operate, each of them
sensors and sensor systems.
On the basis of the proposed classification, we have developed mathematical
performs a limited class of problems.
The main advantage of the second approach is the simplicity of robots’ and func-
model of combined aggregate-modular robot that meet following requirements:
tional modules’ manufacturing, and, as a consequence, a higher reliability of the overall
1. Each module is presented as a graph vertex with emanating from him
system, that in the context of space research is a critical parameter. Also it should be
«hanging» outgoing edges that represent unified interfaces that may be attached to other
noted that the specialized robots, which have been formed from different functional
nodes. Examples of various unified modules are shown in Fig. 1.
modules, have less redundancy for the task. This improves the efficiency of the robotics
All robotic objects are described as a network graph G (Fig. 2). A source of such
system and help to achieve the optimum of the quality criteria, namely: accuracy rate of
network is always a transport platform or another movement system for mobile robot. A
the operation, cost of operation in the terms of energy and fuel, runtime of the task and
drain of this network is a dummy node.
etc.
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Reed – Solomon Decoders for Satellite Communications
Zhibin Liang
Advisor: Wei Zhang
School of Electronic Information Engineering Tianjin University
Fig. 1. Various modules:
1 – transport platform with three unified inter-
Fig. 2. Example representation
faces; 2 – manipulator with one interface;
robot as network.
3 – computer vision system.
Mathematical model assumes the existence of a vector estimation function of the
current solution – network graph G. This function is named F(G), and should estimate
the performance of combined robot using characteristics of individual modules;
Mathematical model assumes the existence of a system of functional limitations
fi(F(G)), which is formed according to functional requirements of the robot’s task;
Mathematical model requires an optimization criterion of functioning quality for a
particular purpose J(F(G)).
The requirements for the problem of finding the optimal configuration of aggregate-modular robots can be formulated as follows: it is necessary to generate a graph G*,
which satisfies the functional limitations fi(F(G)) and gives minimum to the optimization
criterion J(F(G)).
The proposed mathematical model describes the NP-complete optimization problem. During the research of the following types of methods and algorithms that can be
used for solving NP-complete problems were considered:
exhaustive search algorithms or brute-force search;
approximate and heuristic methods that involve the use of a priori rates and
heuristics to select the elements of the solution;
branch and bound method, involving discarding obviously suboptimal decisions
according to some estimates.
At the current stage of research, we have classified the functional modules of robots, have designed graph network model for combined robot, have created a software
implementation for the proposed model, as well as the methods for evaluating solution
options that were obtained using our model.
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REACTION WHEEL FOR ATTITUDE CONTROL OF SMALL SATELLITE
«Sputnik-1» is the first Earth satellite. It was launched from Baikonur cosmodrome on October 4, 1957. It lasted 92 days and made approximately 1400 orbits
Polyakov M.V., Kolomeitsev A.A. , Balandina T.N.
Scientific advisor: Dmitriev V.S., Doctor of technical science, Professor
Department of Precision Instrument Making, Tomsk Polytechnic University,
Tomsk, Russia,e-mail: [email protected]
Astronautics became a practical discipline in the 30th years of the 20th century.
Konstantin Eduardovich Tsiolkovsky was a Russian and Soviet rocket scientist and pioneer of the astronautic theory. Tsiolkovsky’s calculation shown, that space flight is a
near future. His works later inspired leading Soviet rocket engineers such as Sergey
Korolev and Valentin Glushko and contributed to the success of the Soviet space program.
around Earth. It reentered Earth’s atmosphere and ceased to exist on January, 1958.
The second half of the 20th century is the era of manned spaceflight. Yuri Alekseyevich Gagarin, Soviet pilot and cosmonaut, is the first human to journey into outer
space. His «Vostok» spacecraft completed an orbit of the Earth on 12 April 1961.
In the 1960-1970-ies Soviet cosmonauts demonstrated the ability of man to work
outside the spacecraft, and from 1980-1990-ies people live and work in conditions of
weightlessness.
Nowadays, there is tendency to reducing mass and dimensions of spacecrafts, i.e.
tendency to building and using of small satellites. Department of Precision Instrument
Making of Tomsk Polytechnic University develops the basic functional elements of the
small satellite.
Hermann Julius Oberth is considered one of the founding fathers of rocketry and
astronautics. His early books «The Rocket into Interplanetary Space» (1923), and «Ways
The paper presents construction of reaction wheel (RW) for microsatellites.
Nominal momentum of RW is 0.2 N·m·s. diameter – 70 mm. Reaction wheel consists of
to Travel in Space» (1929), established the scientific basis for a technology, which en-
rotating flywheel driven by an internal brushless direct current motor. Flywheel is de-
abled mankind to leave the planet Earth.
signed such, that it’s mass is concentrated on the outer edges to provide maximum iner-
Robert Goddard was an American professor, physicist, and inventor. He created
tia for minimum mass. Cross-section of reaction wheel is shown in Fig. 1.
and built the world's first liquid-fueled rocket, which he successfully launched on March
Brushless DC electric motor consist of stator 1 (mounted on housing 2) and rotor.
16, 1926. Goddard and his team launched 34 rockets between 1926 and 1941, achieving
Rotor consist of inductors 3, permanent magnets 4 (mounted on flywheel 7) and induc-
altitudes as high as 2.6 km and speeds as high as 885 km/h.
tors 5 (mounted on shaft 6). Rotor suspended on ball bearings 10 encased in a housing 2.
Wernher von Braun was a German rocket engineer and space architect. He is considered to be the founder of rocketry and astronautics. He was one of the leading figures
Housing 8 is used for installation of reaction wheel on the satellite. Protecting cover 9
provide protection of RW functional elements.
in the development of rocket technology in Germany during World War II and, subse-
Technical characteristics of presented reaction wheel:
quently, in the United States. He is credited as being the «Father of Rocket Science».
dimensions: 70×70×50 mm;
Great Russian scientist S. P. Korolev continued the work of Tsiolkovsky in Rus-
nominal torque: 0,02 N·m;
sia. Korolev was the lead Soviet rocket engineer and spacecraft designer in the Space
nominal momentum: 0,2 N·m·s;
Race between the United States and the Soviet Union during the 1950s and 1960s. He is
maximal angular speed: 6000 RPM;
considered as the father of practical astronautics. He headed the Group for the Study of
mass: 500 g;
Reactive Motion (GIRD). Group designed and launched the first Soviet experimental
lifetime: 5 year;
liquid rocket (GIRD-10).
supply power: 0.64 W at 2000 RPM;
supply voltage; 12±3 V.
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PERFORMANCE ASSESSMENT OF BEIDOU
SATELLITES NAVIGATION SYSTEM
Xuying Ma, Huan Xie, Weiyue Li, Yizhe Zhang
College of Surveying and Geo-Informatics, Tongji University, Shanghai, China,
email:[email protected], [email protected]
This work is supported by Natural Science Foundation of China (Projects:
41074018)
Introduction
China’s global navigation satellite system, i.e. BeiDou Navigation Satellite System, has been developed independently. Currently, BeiDou works as the third mature
navigation satellite system following the former GPS and GLONASS. The system conFig. 1. Construction of reaction wheel (1 – stator; 2, 8 – body frame; 3, 5 – inductor; 4 – magnets;
6 – shaft, 7 – flywheel, 9 – protecting cover, 10 – ball bearing
sists of three different parts: space, ground and client. It can provide positioning, navigation and timing services of high precision and reliability within the scope of the world.
Considered reaction wheel is effective for using in attitude control system of small
satellite (especially micro- and nanosatellite), because meet the requirements of mass,
dimensional and energy consumption minimization.
Fig. 1. BeiDou Satellites Navigation System.
1.1. Space Constellation
The construction plan of BeiDou is divided into three parts, and currently, China
is in its second step: Aimed to construct a regional navigation satellite system providing
service for areas in China and its surrounding areas. By the end of 2012, BeiDou system
comprises 5 satellites in Geostationary Orbit (GEO), 5 satellites in Inclined Geosynchronous Orbit (IGSO) and 4 satellites in Medium Earth Orbit (MEO). When fully deployed
by the end of 2020, the space constellation will consist of 5 GEO, 27 MEO, and 3 IGSO
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satellites respectively. Then BeiDou satellites will offer complete global coverage, simi-
1.2
5
0
GPS RMSN=1.66m
-5
-10
BD2 RMSN=3.30m
dE [m]
The time reference for the BeiDou is the BeiDou navigation satellite system Time
as the basic unit for continuous accumulation. The start epoch of BDT was 00:00:00 on
January 1, 2006 of Coordinated Universal Time (UTC). The coordinate reference for the
8
12
epoch [h]
16
20
24
GPS RMSE=1.88m
0.8
BD2 RMSE=1.42m
5
G+B RMSE=1.13m
0
-5
-10
-15
0
4
8
12
epoch [h]
16
12
epoch [h]
16
20
0.6
24
0.4
15
10
dU [m]
(BDT). BDT adopts international system of units (SI) seconds, rather than leap seconds,
4
15
10
1.2. Time System and Coordinate System
N
E
U
Tongji Station
1
G+B RMSN=1.38m
-15
0
[cm]
dN [m]
lar to the GPS and GLONASS.
15
10
5
0
GPS RMSU=4.49m
-5
-10
0.2
BD2 RMSU=4.95m
G+B RMSU=4.19m
-15
0
4
8
20
24
0
11/08
Fig. 2. Single point positioning results
of BeiDou and GPS.
BeiDou adopts the China Geodetic Coordinate System 2000 (CGCS2000).
1.3. Signal Specifications
11/09
11/10
11/11
11/13
Observation time[day]
11/14
11/15
Fig. 3. Single epoch baseline
positioning results of BeiDou.
2.3. Precise Positioning Performance
The BeiDou satellite navigation system broadcasts triple frequency signals: B1, B2
In precise engineering surveying, deformation monitoring, precise navigation and
and B3. The signals on B1 and B2 are the sum of channel I and Q which are in phase
some geodesy research, we need more accurate location services. Precise relative posi-
quadrature of each other. The frequency of B1, B2 and B3 signals are 1561.098MHz,
tioning technology can provide us centimeter or even millimeter level location services.
1207.140 MHz and 1268.52 MHz respectively. The transmitted signal is modulated by
Relative positioning, as a traditional GNSS positioning solution method, can weaken the
Quadrature Phase Shift Keying (QPSK).
relevant error dramatically and obtain positioning results of high accuracy. In this sec-
2. Application and Performance Assessment
2.1. Accuracy of Orbit
Generally, we can calculate the coordinates of satellites by using broadcast or precise ephemeris. From the data published by official agencies and relevant research institutions, we can learn that the accuracy of broadcast and precise orbits is about 3~5m and
20cm respectively.
tion, we assess the performance of single epoch baseline solution based on phase observations of BeiDou. We collected one short baselines data using UB240-CORS BD2/GPS Dual-System Quad-Frequency (GPS: L1, L2; BD-2: B1, B2) receivers produced
by UNICORE Communications Incorporation. The short baseline in Shanghai is
470.3009 m and the observation period is from Nov 8, 2012 to Nov 15, 2012. The sampling interval is 1 s. Results in Fig. 3 show that the positioning accuracy of short baseline is about centimeter level. This indicates that the BeiDou has begun to have high pre-
2.2. Navigation Performance
cision positioning capability.
Satellites navigation system is widely used for vehicle navigation and cell phone
location services. The principle of these applications is single point positioning technology. Using at least four satellites pseudo-range observations, by means of space rendez-
3. Summary and Conclusions
BeiDou Navigation Satellite System is China’s global navigation satellite system
which has been developed independently. A regional navigation satellite system provid-
vous solver, we can obtain the coordinates of receiver quickly. From the results in Fig. 2,
ing service for areas in China and its surrounding areas has been established. Currently,
the BeiDou positioning accuracy of horizontal, vertical and three-dimensional is about
BeiDou works as the third mature navigation satellite system following the former GPS
3~4m, 4~6m and 7~10m respectively. This result has satisfied the accuracy requirements
and GLONASS.
of basic navigation applications.
By the end of 2020, there will be 5 GEO satellites and 30 Non-GEO satellites.
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The performance of BeiDou will be significantly improved.
USING SMALL SATELLITES FOR COMMUNICATION WITH THE UAV
The open service is free to all users with point positioning accuracy of 10 m, tim-
Alexander Krasnyanskiy, Ivan Malygin
ing accuracy of 20 ns and velocity accuracy of 0.2 m/s currently.
The positioning accuracy of short baseline solution is about centimeter level.
BeiDou has begun to have high precision positioning capability.
Department of Communication Equipment and Technologies, Institute
of Radio Electronics and Information Technologies, Ural Federal University,
Yekaterinburg, Russia, e-mail: [email protected]
One of the modern challenges of unmanned aircraft is the inability to maintain a
broadband connection (eg, for video transmission) with no direct line of sight between
the UAV and the ground control station. Taking into account the small work altitude of
small UAV (mass up to 50 kg ) and the curvature of the earth's surface ( direct radio link
) , you can restrict bandwidth channels for large data transfers distance 100 ... 150 km.
Without the need for operational monitoring of the position of the UAV and the environment, the video can be recorded on-board storage for later retrieval and processing
after landing UAV. However, when using the UAV there are situations that require
quick assessment of the information and subsequent decision, such as forest fires, search
for missing persons, monitoring and emergency areas. In this case, broadband communications via satellite is one of the possible solutions.
The technical complexity of creating broadband communication channel between
the UAV and small companion is small energy channel on both sides - UAVs or satellite
has no power supply enough power to the transmitter. In addition, placing the UAV antenna with large dimensions is difficult, and the lack of a small satellite positioning
means is not possible to place it in orbit strictly towards the antenna toward Earth.
Potential satellite communication system for such a class may have the following
requirements:
Duplex communication system for transmitting commands from the ground station and the UAV receiving its video stream.
Data rate of at least 1-2 Mbit / s for video format HD-720p and 90-100 bytes of
telemetry information.
Wide constant communication zone.
Low cost of operation.
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Since the placement of small satellites in geostationary orbit is quite difficult, especially consider building a system supporting satellites at low orbits with heights ranging from 220 to 600 km at apogee. Advantages of this system:
Less compared to the spacecraft in geostationary orbit, the satellite design requirements, and hence its lower cost;
A higher signal / noise ratio;
Energy of signal 50 mW - 1 W for the space segment, 2-3 W for ground;
Easy start-up, the possibility of operational maintenance and replacement;
Fig. 1. Appearance of UAV.
The possibility of constructing «Mesh» network in space segment;
Use passive antennas with wide directional diagram;
The use of satellites in low orbits has advantages and disadvantages. It seems ob-
However, you must not forget about the disadvantages of such a system:
vious that in the next 10 years will be designed and implemented satellite constellation is
Need to use at least three satellites in the same orbit for a constant connection in a
designed for civilian UAV service that allows to transmit broadband signals beyond di-
any geographical area and 60-70 satellites to cover 100 % surface of the earth;
rect radio, thereby increasing the possibility of drones and expanding its scope.
Short satellite lifetime due low orbit - about -2 years;
Delay of video streaming is commensurate with the delay in the transmission via
geostationary satellites, due to the fact that the signal from the UAV to the ground station can be relayed through several satellites;
Complexity antenna design on board the UAV and the ground station, using servo
drives;
The result of the experimental work on the project was the creation of a family of
light c UAV ability to integrate satellite communications system, a typical representative
of which has the following characteristics:
Weight, kg
Dimensions, length x width x
height, mm
Engine power, W
Payload, kg
Type and capacity of the battery
Flight time
15
1800 * 3000 * 400
2200
7
Li-po 6S1P 5000 mAh (3pcs)
180 min
Appearance UAV shown in Figure 1.
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SATELLITE NAVIGATION BASED ON PULSAR
algorithmic flow of the X-ray pulsar navigation are described. The comparisions between the X-ray pulsar navigation and other navigation systems are made. Differential
Guo PengBin, Guo XiLiang, Wang Kai, Sun Jian
State Key Laboratory for Strength and Vibration of Mechanical Structures,
Xi'an Jiaotong University, Xi'an, P.R. China, e-mail: [email protected]
At present, spacecraft navigation systems mainly include the satellite navigation
observation equations are derived and their ability of eliminating and reducing observation errors is investigated. The X-ray pulsar navigation algorithms about the timing correction, attitude determination, velocity determination and positioning are generally
summarized.
system such as GPS, the celestial navigation system such as MANS and the radio navi-
The transformation of the time of arrival(TOA) observed onboard spacecraft to
gation system such as DNS. However, there are many limits of the above-mentioned
the TCB/TDB time at the barycenter of the solar system and the pulsar timing model re-
spacecraft navigation methods in terms of real-time, cost and resource, which makes it
fining are researched. The magnitude of order and variations of Einstein delay, Shapiro
difficult to satisfy the high-accuracy navigation requirements of some special tasks.
delay, Roemer delay are statistically analysed .
Navigating a spacecraft with the existing GPS system restricts the maximum alti-
In order to verify the design of the filter， mathematical simulation is conducted
tude of the satellite to 20000 km. Clearly this system cannot be used for interplanetary
using nonlinear Kalman filter. The orbital parameters of the spacecraft are estimated us-
trajectories；General celestial navigation system relies on celestial position, height and
ing EKF filter in two views of not considering and considering clock error. The results
other information measured for navigation, For deep space spacecraft which needs to
prove that clock error affects positioning accuracy greatly and time synchronization
work long hours, it exists positioning accuracy is low, the output is not continuous, sus-
technology plays a very important role in autonomous navigation technology.
ceptible to outside influence shortcomings. Currently the most common means to track
X-ray pulsar navigation is an inevitable choice of space technology’s future de-
spacecraft on interplanetary orbits is to use a network of large radio telescopes. This
velopment, and the results of this study is significant to pulsar time synchronization
method does not provide an autonomous means to determine the spacecraft’s position,
technology.
the signal delay between the ground station and spacecraft increases with distance and
the precision of the position determination decreases with distance. According to, an inherent angular precision on the order of 10 nanoradians is achievable using the Deep
Space Network. This corresponds to a position accuracy of 1.5 km for a distance of one
astronomical unit from Earth.
The pulsar, known as nature's most stable clock, is a high-speed rotating neutron
star. Pulsar navigation has been noticed gradually because of its unique advantages in
deep space navigation. X-ray pulsar navigation is a new autonomous navigation technology to provide spacecraft navigation information of the position, velocity, time and attitude. X-ray pulsar navigation technology has important strategic significance and huge
development potential due to its anti-interference ability, high reliability and application
for a wide range.
Necessary qualifications of pulsars for the X-ray pulsar navigation are proposed
through the analysis of pulsar character. The principle and basic elements and navigation
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LET THE UNDERGRADUATE STUDENTS JOIN THE TEAM
Hong Kong University of Science and Technology by means of sending young teachers
OF DESIGNING AND MAKING THE MICRO SATELLITE
abroad for further education, academic communication and so on. We send teachers and
AN INTRODUCTION OF THE ZDPS-1 MICRO SATELLITE
AND CELL-SAT PROGRAM OF ZHEJIANG UNIVERSITY
1. Micro satellite platform-a general profile of the Micro satellite research center
of Zhe Jiang university
1.1. History
Set up in Dec,2008, Micro satellite research center of Zhe Jiang University was
students abroad for visiting research and academic communication.
2.3. Scientific research projects
Center’s research work is highly valued by country’s related departments and has
undertaken a batch of scientific research projects from 863,973,NCFS(National Natural
Science Foundation) and various ministries. We get a yearly scientific research fund of
nearly ten million on average.
advocated by Chinese senior expert in aerospace as well as academician Shen Rongjun,
3. Representative project-ZDPS-1A project of Zhejiang University
who is also the dean of the School of Aeronautics and Astronautics, Zhejiang university.
3.1. Background
Research center was co-built by the School of Aeronautics and Astronautics and the de-
ZDPS-1A is a kilo-weight micro satellite whose research work was based on the
partment of information and electronic engineering. The initial members mainly come
eleventh Five –Year plan’s pre-research project of the PLA General Armament Depart-
from the pico-satellite program of Zhejiang University and the MEMS research team of
ment. It was planned to have a flight test by being launched together with another satel-
Microelectronics and solid-state electronics profession.
lite. Its main tasks include having a integration testing for several key techniques of the
pico-satellite, examining pico-satellite’s overall design and stand-alone parts, lay foun-
1.2. Research content
Tasks in our research center include: building of the micro-nano, realization of
dation for pico-satellite’s further development and application.
ZDPS-1A was mainly researched and developed by professors, doctors and mas-
satellite’s communication and control, satellite’s attitude control, development of the
ters of Zhejiang University. On september the twentieth,2010, two ZDPS-1A satellites,
electronic system on satellite, micro-nano satellite formation and MEMS technology.
whose total weight was 3.5 kilogram, was successfully launched in Jiuquan Satellite
2. Brief introduction for center’s scientific research ability
2.1. Teacher resources
Center is mainly engaged in the research of micro-nano satellite、MEMS and
Launch Center , China. It’s China’s first batch of kilo-weight micro satellite and also one
of world’s most comprehensive pico-satellites. During the validation period, every function was as good as expected. So this project was successfully finished. Till now, two
ZDPS-1As are still functioning well with a total working time of more than one year.
sensor as well as talent cultivation. Center is now equipped with 22 staffs, including
3.2. Project contents
three professor and doctoral supervisors and five associate professors. Center has more
than 50 masters or doctors and nearly a hundred undergraduates. Our center employs
ZDPS-1A’s Main tasks:
several academicians in aerospace , experts and well-known scholars home and abroad
1. Testing for pico-satellite’s basic functions: By building pico-satellite’s link
as part-time professors to provide guidance for our research work.
with the earth, testing communication, we can test pico-satellite’s environmental adaptability and the function of its basic parts such as power, network measurement and con-
2.2. International communication
trol, heat control and structure.
Our center has built good relationships with University of Tokyo, Tokyo Institute
2. Pico-satellite’s attitude control test: Test pico-satellite’s attitude measure and
of Technology, Royal Institute of Technology in Sweden, University of Edinburgh,
control effect by supervising related status data of the satellite. Pico-satellite sets its atti-
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tude using magnetism assisted by MEMS Spinning Top and the sun sensor, and it uses
At the same time, we found that the influence of the noise is very low, so it was unnec-
single shaft fix biased momentum wheel to control its attitude.
essary to use filtrate process as the theory required. From that, we realized that in some-
3. Microminiaturized device test: Using a flight test for hemisphere imaging pano-
times, perfect in the theoretical analysis does not mean the best, but an incomplete algo-
ramic optical camera that pico-satellite carries, MEMS acceleration speed sensor and
rithm is also a good choice.
angular velocity sensor to examine its environment adaptability.
Student
Project title
leader
Jiang Jun- Satellite of forest fire detecjun
tion
4. High efficient three junction GaAs solar cell test: By supervising solar cell’s
current and voltage output when pico-satellite is under different illumination angle and
load, we can test and evaluate solar cell’s behavior in real space environment.
CellSat project Introduction.
In order to discover and develop talents in aerospace, our institute specially set up
Cell Sat Scientific research training project. Cell Sat Scientific research training project’s participants are mainly undergraduate students. It encourages students to form
teams with a background of various subjects by crossing disciplines. It aims at promoting undergraduates’ operational abilities. As well as launching a satellite, undergraduates
can also learn a lot of extra-curricular knowledge and at the meantime they will apply
their professional knowledge to reality, which enriches their knowledge and deepen their
understanding for in-class contents.
The first Cell Sat project was introduced in Nov, 2012, when many groups signed
up. The selection was completed in Dec, 2012, with ten groups got the approval of professors, also got the permission and encouragement to begin. Project names are showed
as below (see table):
institute
College of Electronic Engineering
School of Biosystems EngiWind speed measurement satJiang Chiyu
neering and Food Science
ellite
Liang Yuan Communication platform
College of Zhu Ke-zhen
Ma Xian- Communication between sat- Department of information
grong
ellites
and electronic engineering
School of Biosystems Engineering and Food Science
Wang Zhen Ozone hole
water quality monitoring buoy College of Electronic Engiand data collecting satellite neering
Communication between satDepartment of information
Xu Lan
ellites and ground for emerand electronic engineering
gency
Yan Qing- Designing of geomagnetic
Department of information
hui
field sensor
and electronic engineering
Zhang Hu- Sun Tracking System based Department of mechanical
ichao
on Micro satellite
engineering
Department of chemical engiThe experiment platform
Zhou Chao
neering and biological engibased on microgravity
neering
Wu Jiupeng
grade
Two
Two
Two
Three
Two
Two
Two
Three
Two
Three
Finally in Dec, 2013, all the satellites were carried by a model helicopter, finish-
I have finished the project»Sun Tracking System based on Micro satellite».So let
me introduce something about this project. This satellite has only a very simple function.
That is using the solar panel and camera module to find the direction of solar, then lock
the sun into the center of the image. At the start of this project, we tried to take photo of
ing all the function tests. Data received from satellites is correct, so all the function was
completed.
After all, I realized that undergraduates can also build a satellite. Although the
knowledge taught is limited, students can learn what they want from anywhere.
sun using the camera onboard. But the problem is that the quality of those photos was
terrible. It was hard to adapt the requirement of the algorithm. Considering the small diameter of the lens, we replaced the camera module with OV7620. After that, we were
delighted to find that the quality of the photo was much higher. But, a problem came out
that the algorithm was running too slow. A 640*480 pixels frame would take more than
10 seconds to process. So we simplified the algorithm, some filtrate process was removed. Then the processing time was much faster than before, about 1 second per frame.
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SCV costs and RAAN difference taking into account the RAAN precession, so that sig-
THE RESEARCH OF THE CHARACTERISTIC VELOCITY REQUIRED
FOR MAINTENANCE AND REPLENISHMENT OF THE SATELLITE
CONSTELLATIONS OPERATING AT THE NON-COPLANAR
CIRCULAR ORBITS
nificantly less velocity is needed for greater angle correction. Remarkable SCV costs decrease opportunity is also shown for the essential RAAN differences.
In case of the need for changing the semi-major axis in addition to the phase angle
and the RAAN difference the graphical relations were found which allow evaluating the
minimum of SCV costs using the RAAN precession for the different initial orbit heights
Dmitriy Grishko
Bauman Moscow State Technical University, Russia 105005 Moscow,
2-nd Baumanskaya, 5
The significant increase of quantity of the satellite constellations operating at the
Near Earth Orbits takes place nowadays, the renovation of the existing constellations for
and for the different number of passive circuits, the explication of observable asymptomatic behavior of the SCV costs function is given. The initial data influence on the SCV
costs minimum absolute value and displacement direction is investigated. The relationship between the orbit inclination and SCV costs for the semi-major axis correction is
demonstrated taking into account the direction of the rotation.
the purpose of satellite number growth is being accomplished. These processes make it
The situation is the mostly complete one when it is necessary to correct all four
necessary to thoroughly investigate the replenishment problem when the reserve satellite
mentioned parameters. For this case the relationship between the direction of changing
has to be repositioned in place of non-operating satellite, analogous problems with rela-
the inclination and SCV costs, the influence of the RAAN difference on the relationship
tion to summary characteristic velocity (SCV) costs concerned with the satellite ap-
between SCV costs and inclination difference are demonstrated. It is shown that it is
proaching and repairing should be considered also. There is an acute need for the solu-
more profitable to change the inclination for a few degrees using the RAAN precession
tions of this type of missions if the only one launch vehicle delivers several satellites to
with the addition to semi-major axis correction at the low orbit then to do it at the high
one point of the orbit and they have to be arranged on different positions.
orbit, where the influence of the Earth gravity field’s nonsphericalness is weaker. While
Regarding the constellations based on the circular orbits there are four main variants of initial data which differ from each other by the quantity of orbital parameters
which must be corrected. These orbital parameters include phasing angle Δu, difference
in right ascension of the ascending node (RAAN) ΔΩ, difference in semi-major axes Δa
and inclination difference Δi. All four variants were considered in this study, the effects
appearing because of the certain initial data combination were analyzed.
In the phase angle changing mission the analytical relations were found which determine a number of passive circuits which is a compromise between time and SCV
costs. For the same mission was also established the focal parameter and number of passive circuits influence on the value of inclination by which the maximum of SCV costs is
investigating the complete case the coincidence of tendencies in the relationships between SCV costs and different parameters with the results obtained for the first two variants of initial data was detected.
The study is devoted to the circular and near-circular orbits which are notable for
being mostly usable for the current and prospective constellations of Earth remote sensing, positioning and communication systems. The results seem to be useful in temporal
and energetic costs minimization while projecting and exploiting these types of constellations. After all, the obtained results are applicable in exploiting the maneuvering space
vehicles which are supposed to be designed for large-sized space debris collection.
achieved.
In the RAAN changing mission the opportunity of notable SCV costs decrease is
shown for the case when the difference in RAAN is rather small (few degrees), that is
possible because of the damped oscillations which describe the relationship between
91
92
LilacSat-1: A Student CubeSat Project of HIT
The OBC board uses a STM32L low power ARM processor. Different interfaces,
memory chips, sensors and H-bridges are also provided in the OBC board. FreeRTOS
Ning Mingfeng, Wei Mingchuan, Zhang Jian
Research Center of Satellite Technology, Harbin Institute of Technology,
Harbin, China
and CSP protocol will be used.
The communication subsystem of LilacSat-1 consists of a software defined amateur radio (SDAR) transceiver, an S-band receiver (SRX) and the antennas. Different
Harbin Institute of Technology(HIT)was founded in 1920. Now it have 3 cam-
frequencies are used for telemetry, command and amateur radio. SDAR is a VHF/UHF
puses in Harbin, Weihai and Shenzhen. HIT is a member of the Chinese C9 league, with
SDR transceiver platform. The latest version makes use of the analog outputs of
science, engineering and research as its core. HIT has served in Chinese space programs
ADF7021 with the help of the AAUSAT3 team. A codec samples the IQ signal at 96
since 1950s.
kHz, and the maximum output power is about 1.7 W. The baseband of ADF7021 is not
HIT Research Center of Satellite Technology was founded in 1995. It has a staff
of 28, and about 80 postgraduates. It has launched 3 micro-satellites, SY-1 in 2004, SY3 in 2008 and KZ-1 in 2013.
wasted. An ATMega328 running arduino works with it as a backup low power transceiver.
The U/V monopole antennas are made of pseudo-elastic Ti-Ni alloys.They are de-
Lilac is the city flower of Harbin and a symbol of HIT. That’s the meaning of the
name LilacSat.
signed to bend outside the CubeSat body before deployment.
For the structure, the batteries can be moved to adjust the center of gravity;the
LilacSat-1 is a part of the QB50 constellation. It is a typical 2U CubeSat with a
QB50 INMS sensor unit, a camera and an amateur radio transponder as its payloads. Its
missions include:
PCBs are parallel with Y axis to bypass the interfaces.Static analysis, random vibration
analysis and modal analysis are used to verify the design.
Passive thermal control is used. Temperature distributions of different situations
Upper atmosphere science;
Demonstration of amateur radio technology and providing communication resources for radio amateurs ;
Development of a low cost CubeSat platform by the students.
The CubeSat is expected to be launched into an orbit of 350 km, 98 degrees incli-
are analyzed with ANSYS.
HIT Amateur Radio Club (BY2HIT) will function as the ground station. It is a
student club of HIT. The station is licensed on HF and VHF band, with omni-directional
antennas and portable yagies for satellites now. New high gain yagies with rotator and a
transceiver are in plan.
nation in 2016.
LilacSat-1 uses magnetic control, with magnetorquers as its actuators, and gyroscope, magnetometer, sun sensors and a BD2/GPS receiver to determate its position and
attitute.The CubeSat is designed to be aerodynamically stable. The data processing of
The LilacSat-1 team is a student team with about 15 active members, majority of
whom are undergraduates of different fields. Most work was done by the students in
spare time, but we do it out of interest and we have confidence to make it.
ADCS is done in OBC.B-dot detumbling and PD 3-axis stabilization is used. The target
accuracy is 2 degrees for determination and 10 degrees for pointing.
The CubeSat is powered by 18 solar cells and 3 Li-ion batteries. An EPS board
functions as the power controller. The main power path does not relyon a MCU. The
subsystem can remain working on only solar power if the batteries fail open or short.
93
94
GNSS SATELLITE CLOCK DENSIFICATION: FROM 5-MIN TO 30-S
Yize Zhang1, Bin Wu1, 2, Huan Xie1, Xuying Ma 1, Weiyue Li1
1
To solve the problem, we use an epoch-differenced GNSS clocks estimation algorithm to get the 30-s sampled GNSS clocks.
2. Data Processing
College of Surveying and Geo-Informatics, Tongji University, Shanghai, China;
2
Shanghai Astronomical Observatory, Shanghai, China,
email: [email protected], [email protected]
Fig. 2 shows the 110 global GPS and GLONASS stations we use in our data processing.
1. Introduction
Currently, the International GNSS Service (abbreviated as IGS) has provided precise GNSS satellite orbits product at the interval of 15 minutes. It can be interpolated
with almost no degradation of accuracy at the user-need epoch by sliding polynomial interpolation. However, the accuracy of satellite clocks dramatically degrade with the increase of interpolation interval and no proper method could solve this problem well
Conventional satellite clock estimation is a time consuming work with the increase of
data sampling and size of network.
With the development of GLONASS system, multi-GNSS applications including
PPP emerge as a big enhancement to the current applications. As a result, the parameters
Fig. 2. IGS network processed in the GNSS routine of SHA.
to be estimated increase by a big amount (Fig. 1), which introduces further challenges
for the production of high-rate GNSS clocks
Fig. 3 summarizes the GNSS clock estimation procedure. The average computation time of the clock densification procedure is about 3 minutes (in Linux environment
with 2.40 GHz CPU processors), which indicates the efficiency of this approach.
Fig. 1. Growth of the number of ambiguities and the other parameters versus the increase of the
Fig. 3. The 30-s GNSS
number of stations tracking a constellation of 32 GPS satellites and 24 GLONASS satellites.
clock generation.
Fig. 4. Difference of the densified 30-s
GNSS clocks with that provided
by ESA.
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96
3. Results
AEROLOGICAL SUPPORT OF LAUNCHES FROM SPACEPORT
To assess the quality of the densified 30-s GNSS clocks, we calculate the differ-
«VOSTOCHNY»
ences between our clocks and the IGS final clocks. Fig. 4 shows the densified 30-s
GNSS clocks compared with that provided by ESA (European Space Agency). It proves
that the difference about 10ps for GPS and 12ps for GLONASS in RMS, which indicates
Anastasia Komissarova, Ivan Malygin
Department of Communication Equipment and Technologies, Institute
of Radio Electronics and Information Technologies, Ural Federal University,
the validity of this algorithm.
Yekaterinburg, Russia, e-mail: [email protected]
Meanwhile, we use Allan deviation to assess the quality of densified 30-s clocks.
Fig. 5 shows the Allan deviation for five satellite clocks, representing satellite groups of
One of the main sources of meteorological information is aerological measure-
GPS Block IIA, Block IIR, Block IIR-M, Block IIF and GLONASS-M, respectively.
ments. The most widespread method of aerological investigations is radiosonde observa-
From the figure we see that the Allan deviation of the densified clocks at different sam-
tion of the atmosphere, when a radiosonde with meteorological sensors and a transmitter
pling interval is the same, which proves that the densified 30-s clocks have the same
is sent to the atmosphere on a gas-filled balloon. Radiosonde observation provides mete-
quality of the original 5-min clocks.
orologists with precise values of measured atmospheric parameters at heights from the
High-rate kinematic PPP requires precise high-rate GNSS satellite clocks. To reduce the inner-consistence and to reflect the system biases, Bernese software is used for
kinematic PPP. The results proves the advantage of the high-rate clocks.
ground surface to 30 – 40 km.
Data collected by radiosondes is used for making weather forecasts. As predicting
the weather is extremely important for space vehicles launching, sounding systems are
used in many spaceports.
Radiosonde sounding systems can be divided into two categories according to the
method of radiosonde coordinates determination: radio-locating and radio-navigational.
In radio-locating method azimuth, angle of elevation and either slant range, or lifting
height of the radiosonde are measured to determine the coordinates. Radio-locating radiosonde sounding systems consist of a radiosonde and a radar station, which calculates
radiosonde coordinates and receives information signal from it.
Advantages of radio-locating systems are high noise immunity and long tracking
Fig. 5. Allan deviation comparison
Fig. 6. Densified clock
range. Disadvantages are the following: big mass and dimensions of radar station, the
of the densified clocks.
in kinematic PPP.
need of strict spatial orientation of station antenna, which is inconvenient in mobile ap-
4. Conclusions
This paper focuses on the 30-s GNSS satellite clocks generation algorithm. We
present the efficient and precise epoch-differenced algorithm for the generation of highrate GNSS satellite clock corrections. Results shows that the algorithm is efficiency and
valid. These high quality products could contribute well to the IGS combination, especially for the GLONASS products.
plications, and decrease of accuracy of distance determination when the angle of elevation is small.
Radio-navigational method of radiosonde observation of the atmosphere uses signals
of radio navigation systems. In radio-navigational sounding systems coordinates of radiosonde projection on the ground surface are determined using radio navigation systems. A
height of the radiosonde can be determined either using radio navigation system as well or
on the basis of the value of atmospheric pressure measured by radiosonde sensor.
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98
Radio-navigational radiosonde sounding systems are now replacing radio-locating
systems. The reason is that radio-navigational systems do not need to determine angular
the radiosonde GPS/GLONASS receiver in differential mode. It helps to increase the accuracy of radiosonde coordinates determination.
coordinates of the radiosonde. As a result, radio-navigational systems have several bene-
A block diagram of «Polus» system is presented in Fig.1.
fits in comparison with radio-locating systems. First of all, non-directional antenna can
Main characteristics of «Polus» system are the following:
be used. Secondly, there is no need for antenna to be on fixed position, and as a result
maximum lifting height of radiosonde: 40 km;
these systems can be mobile. Moreover, as satellite radio navigation systems are devel-
maximum tracking range: 250 km;
oping intensely, coordinates of radiosonde can be determined more and more accurately,
radio channel frequency range: 400.15 – 406.0 MHz;
while receivers of navigational signals become cheaper and cheaper. As a result, ra-
radio channel bandwidth: 10 kHz;
diosondes, which are not reusable, also become cheaper. Furthermore, in radio-
tuning step: 100 kHz;
navigational systems the accuracy of determination of coordinates does not depend on
range of measured values and root-mean-square errors:
the distance between the radiosonde and the base station, as they are calculated on the
air temperature: from -90 to +50 degrees, maximum error 0.3 degrees;
radiosonde itself.
wind speed: 0 – 200 m/s, maximum error 0.7 m/s;
Disadvantage of radio-navigational sounding systems consists in the fact, that the
wind direction: 0 – 360 degrees, maximum error 1,5 degrees;
usage of non-directional and semi-directional antennas decrease noise immunity. Never-
atmospheric pressure: 2 – 110 mbar, maximum error 1.0 mbar;
theless, this disadvantage can be overcome, by using directional antennas or by design-
relative humidity: 2 – 98 %, maximum error 2.0 %.
ing the radio channel between the radiosonde and the base station efficiently.
Radiosonde sounding system «Polus», designed by our research team, is a radionavigational system. It consists of a radiosonde sent to the atmosphere on a weather bal-
Students of our department also take part in «Polus» system development. To be
exact, they design and assemble printed circuit boards of GPS/GLONASS receivers for
radiosondes and take part in testing of the receivers.
loon and a base station, which receives radiosonde signals and processes them. The ra-
Radiosonde sounding system «Polus» has been tested successfully, including tests
diosonde contains a GPS/GLONASS receiver.
on Baikonur cosmodrome. This system is going to be used for aerological support of
Sensors placed on the radiosonde collect mete-
launches from Vostochny cosmodrome.
orological data, which is transmitted to the base
Navigation satellites
station as well as navigational data. A computer
of the base station forms vertical profiles of
measured atmospheric parameters: air temperature, relative humidity, atmospheric pressure,
400.15 – 406.0 MHz
wind speed and direction. Profiles are formed
Radiosonde
Base station
relatively to the height, but measured values can
be also attached to radiosonde coordinates.
Fig.1. Block diagram
of «Polus» system.
The base station also has a GPS/GLONASS
receiver, which can be utilized conjointly with
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100
NAVIGATION SERVICES BASED ON COMPASS (BEIDOU)
with RDSS and RNSS will be able to provide users with continuous positioning, velocity
measurement and location report services. COMPASS will achieve compatibility with
Weiyue Li, Chun Liu, Huan Xie, Yizhe Zhang, Xuying Ma
GPS and provide equivalent accuracy as GPS.
College of Surveying and Geo-Informatics, Tongji University, Shanghai, China,
email: [email protected], [email protected]
2. Application on navigation and location
а) COMPASS application
1. Introduction
COMPASS (Beidou) Navigation System is an important high-technology investment of China, the second generation of the system is designed consisting of 35 satellites
and will provide 24-hour, global satellite navigation capability, and offered public re-
The system includes three development objectives:
1) General guideline: Quality, safety, application and benefits;
2) High performance, reliability and benefits;
3) To provide regional passive services by 2012.
gional service from 2010. One key advantage of Beidou is the low service cost in marine
positioning and communication services. One can expect that Beidou system will create
a huge potential market of global positioning services, especially in greater China region.
Researches on satellite navigation in China were first initiated in the 1980s.
Mainly learning from the GPS and GLONASS, China had been groping for a development strategy of its own satellite navigation system. It is Academician Chen Yunfang
who first proposed a positioning theory which makes use of two GEOs (Geostationary
Orbit satellite, 35,863 kilometers above the Earth's surface) and user elevation. In 1994,
the project based on this idea was formally approved by the state. A demonstration system of COMPASS was established after the success-
Fig. 2. The full service region (Longitude 84-160 degrees; Latitude 55- -55 degrees).
ful launch of three GEOs between 2000 and 2003.
COMPASS demonstration system consists of three
б) Advantages of COMPASS RNSS+RDSS Services
GEOs, all of which are equipped with RDSS payloads. One of them is also equipped with RNSS experimental payloads. RDSS is its major service, with
the functions of positioning (Three ball fair positioning method), user location report, short message
communication and timing. Phase II of COMPASS
aims at meeting users’ demands in the Asia-Pacific
Fig. 1. Phase II of COMPASS
Navigation Satellite System.
region. A constellation made up of 12 satellites will
be put in place. By 2012, the COMPASS system
101
Fig. 3. Beidou/GPS monitoring architecture.
102
This Fig. 3 shows the constellations between GPS L1 and COMPASS B1, and it
will output single-point precision in 5 meter. The charge of COMPASS RDSS short
DEVELOPMENT OF NOISE-TYPE LINK FOR SMALL SATELLITE
message (1480 bits) is no more than 0.1 RMB, equal to 0.012 EUR. Compared with satellite voice service immediate communication, short message is clearer especially in
jamming environment. And there are some innovation technologies to integrate several
short messages as max 4Kbps narrow band satellite data communication in Chinese civilian marine applications. Chinese government guarantee offer all the PNT and short
message communication service continually even at the satellite upgrade process. As we
know, COMPASS has been in the phase II and the switchover processed smoothly.
Alexey Kulnev, Ivan Malygin
Department of Communication Equipment and Technologies,
Institute of Radio Electronics and Information Technologies,
Ural Federal University, Yekaterinburg, Russia, e-mail: [email protected]
One of problems at design of small satellites is development of the transmitter of a
communication system which has to meet inconsistent requirements:
1. Big range of communication
3. Conclusions
COMPASS (Beidou) provides significant enhancements over the current GNSS.
COMPASS has been largely used as the three-step development strategy planned. Position datasharing and RDSS short message services by COMPASS have been widely ac-
2. Low radiated power supply in a type of restrictions of power food and the sizes
of the antenna caused by the sizes of the satellite.
3. The narrow bandwidth of a transmitted signal limited to possible distortions of
a signal in an ionosphere.
cepted in China. There is a good and broad foundation for cooperation in compatibility
The situation becomes complicated also that it is difficult to position the satellite
and interoperability for GPS and COMPASS. There should be more innovative applica-
in the direction the transferring antenna to the earth as sensors of positioning and cor-
tions in maritime service in the future.
recting engines at small satellites are absent.
Partially the problem can be solved increase in dimensions, and, therefore, and
coefficient of the strengthening, the receiver’s antenna on Earth.
Application in a communication channel «Satellite - Earth» of spread spectrum
signals can become a reasonable solution of the described problem. It is known that the
preference when processing spread spectrum signals is proportional to base of a signal.
Applied in Wi-Fi networks Barker's codes with base of a signal in 11 elements don't possess a sufficient preference at realization of a satellite communication channel. On the
other hand, the superlong pseudorandom sequences used in navigation systems of global
positioning, such as GPS and GLONASS, require the difficult equipment for the formation, which application in the conditions of low power of power supplies of small satellites hardly probably. Standard Spread Spectrum the chipsets offered by such firms as
TI, Intersil, Cypress Semiconductor, RF Micro Devices restrictedly are applicable in satellite communication channels as ZigBee or Wi-Fi are focused on standard market
communications, for example. Obviously, development of the transmitter on several
electronic components is required, from which the generator of pseudorandom sequence
103
104
length than 1000 elements long, the modulator, SAW filters and the output amplifier of
Content
power is main. The following scheme of the spread spectrum signals transmitter is offered:
Fig. 1. Block diagram of the offered spread spectrum signals transmitter for the small satellite.
The most widespread means of power supply of artificial satellites are solar batteries. On
the small satellite in connection with requirements to weight there is no opportunity to install orientation system in space which would turn solar batteries in the necessary direction. There is also no
possibility of installation of reserve solar batteries that the satellite could be loaded from any party.
So, it makes sense to consider alternative sources for recharge in space.
In the nature there is a number of the phenomena and regularities against which the person
tries to fight instead of using. It is possible to refer existence of belts of Van Allen to such phenomena.
Internal radiation belt of Earth was opened by the American scientist James van Allen after
flight the Explorer-1. And an external radiation belt of the earth was opened by the Soviet scientists
S. N. Vernov and A. E. Chudakov after flight the Satellite-3 in 1958.
They represents, as a first approximation, a toroid in which two areas are allocated:
internal radiation belt at height ~ 4000 km, consisting mainly from protons with energy in
tens of MeV;
external radiation belt at height ~ 17 000 km, consisting mainly from electrons with energy
in tens кeV.
It is supposed to use the loaded particles in Van Allen's external belt for a satellite battery
charging.
It necessary to develop protection of the equipment of the satellite from aggressive influence
of the loaded particles (it is necessary to consider both static, and dynamic means of protection).
Operation of the satellite thus assumes use of an elliptic orbit. The satellite has to come into
Van Allen's belt in the perigee. When the satellite leaves in safe part of space, the antenna is exempted from protection and the operating mode of the equipment joins.
105
Medvedsky A. L., Firsyuk S. O. History and perspectives of design of micro-satellites in
MAI .................................................................................................................................... 4
Wang Feng. The Developing Road of Small Satellites in Harbin Institute of Technology ... 7
Victor Leonov. Bauman University Youth Space centre’s experience in development of scientific and educational micro- and nano-satellite technologies.............................................. 10
Neshchimenko V.V., Koftun Y.S., Yurina V.Y. Thermal Control Coatings Based on Hollow
Particles for Small Satellites.............................................................................................. 12
Kharlan A. ASRTU Future Satellite: Design And Mission Goals Discussion .................... 15
Zhou Guanqun, Wang Hui, Liu Xiao. Space Station Accompanying Satellites Design ...... 17
Ridong Zha*, Hong Huang, Fulin Luo, Huanpeng Qu. The Miniaturizing of Small Satellites
Benefits the Most From Mems .......................................................................................... 20
Sun Ying, Xia Guangqing. A New Microthruster for Small Satellites ................................ 24
Taras Plyushko, Elena Lyakhova, Mikhail Denshchikov, SergeyKuperov. Network Coding
Techniques Within The Satellite Communications ............................................................ 26
Vorontsov A., Gravshin V., Petrov D., Glushkov V. Small Satellite Power Supply System
Solutions ........................................................................................................................... 29
Chernyshov A. N., Vorobiev A. L., Vassiliev V. S. Estimation of the possibilities of the multisatellite group of «CubeSat» satellites on the groundwork of both technology and function
restrictions......................................................................................................................... 32
Kosenko I.V., Lopatko K.O., Romashin A.N. Distant Radio Wave Sounding to Detect Forerunners of Earthquakes...................................................................................................... 34
Guohua Kang, Zhou Ye, Xuefen Chen, Ping Shen. The Foundsat Project........................... 36
Xiang Zhang, Xiaokang Yu, Yujie Zhou, Haizhen Gao. Nano/Pico Satellite Technology Progress in Nanjing University of Science and Technology............................................................. 39
Savostyanov Aleksandr. Laser Modules for Ignition of Liquid Rocket Engines ................. 42
BAI Bo, HE Wei, HU Zhi-qiang, YANG Zhong-guang. QB50 Project—What Can We Learn
From It .............................................................................................................................. 44
Demidova V.I., Kopylov A. A., Makukha V.K.,. Morozov K.S. Electronic System of Medical
Sensors.............................................................................................................................. 47
Huang Jianhuang, Chen Shule, Xu Xiangmin. General Automatic Test System For Aviation
Applied In China Southern Airline.................................................................................... 51
Shanwen Liu, Hao Wang, Ye Li, Yunzhuang Zheng, Changyin Dong. Video Transmission
System for Small Satellites................................................................................................ 54
Pavel Belochkin, Kseniya Morunova, Alexey Kochengin, Igor Shulev.The Concept of the
First Student Small Satellite of the South Ural State University............................................ 56
V. Tiunov, S. Chikarenko. Linear Electric Motors for Electromechanical Installations: Constructions, Engineering Calculations and Linguistic Description .......................................... 59
106
Igor Kinzhagulov, Alena Makarova, Anna Malevannaia, Maksim Shuhayeu. Center for Coordination and Control of Small Satellites of University ITMO. Concept of Creation. ....... 62
Kalugin N.V., Muliukha V.A. Development of Representation Methods for Functional Models of Aggregate-Modular Robots...................................................................................... 65
Zhibin Liang. Reed – Solomon Decoders for Satellite Communications............................ 68
Polyakov M.V., Kolomeitsev A.A. , Balandina T.N. Reaction Wheel For Attitude Control Of
Small Satellite ................................................................................................................... 75
Xuying Ma, Huan Xie, Weiyue Li, Yizhe Zhang. Performance Assessment of BeiDou Satellites Navigation System............................................................................................................. 78
Alexander Krasnyanskiy, Ivan Malygin. Using Small Satellites for Communication with the
UAV ................................................................................................................................. 82
Guo PengBin, Guo XiLiang, Wang Kai, Sun Jian . Satellite Navigation Based On Pulsar....... 85
An introduction of the ZDPS-1 micro satellite and Cell-Sat program of Zhejiang University ...........................................................................................................................87
Dmitriy Grishko. The Research Of The Characteristic Velocity Required For Maintenance
And Replenishment Of The Satellite Constellations Operating At The Non-Coplanar Circular Orbits ........................................................................................................................... 91
Ning Mingfeng, Wei Mingchuan, Zhang Jian. LilacSat-1: A Student CubeSat Project of
HIT ................................................................................................................................... 93
Yize Zhang, Bin Wu, Huan Xie, Xuying Ma, Weiyue Li .GNSS Satellite Clock Densification:
from 5-min to 30-s ............................................................................................................ 95
Anastasia Komissarova, Ivan Malygin. Aerological Support of Launches from Spaceport
«Vostochny» ..................................................................................................................... 98
Weiyue Li, Chun Liu, Huan Xie, Yizhe Zhang, Xuying Ma. Navigation Services based on
COMPASS(Beidou) ........................................................................................................ 101
Alexey Kulnev, Ivan Malygin. Development of Noise-type Link for Small Satellite ........ 104
Small satellites, their systems and subsystems, mission concepts and related infrastructure
Изд-во АмГУ. Подписано к печати 31.03.14. Формат 60x84/16. Усл.
печ. л. 6,28. Тираж 150. Заказ 455.
Отпечатано на участке оперативной полиграфии АмГУ.
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THE PROCEEDINGS BOOK

Transcription

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