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IAC–02-P.1.04
UNOSAT: THE FIRST BRASILIAN UNIVERSITY
NANOSATTELITE
Stancato, F.; Manhas ,E. M. Jr;Oliveira, M; Mendes, L. H.;Oliveira, G. O.;Paiva, M.
C.;Cunha, D. K.;Negrão, C
Universidade do Norte do Paraná
Lone, L. P.; Lone T
Universidade Estadual de Londrina
Londrina, PR.
Brasil
Louro, A. C.;
Instituto Nacional de Pesquisas Espaciais
Mônaco, D.
Instituto de Aeronáutica e Espaço
[email protected]
Contacts were made in the
beginning of 2001 to see a launch
possibility as secondary payload at
the third qualification flight test of
the VLS, the Brazilian launcher.
Soon came the positive answer and
the project began.
A very simple nanosatellite
project was chosen. The mission was
going to download 5-parameter
telemetry and one voice message.
The different project parts were
divided
among
the
thirteen
undergraduate students: structure,
radio link, solar panels, energy
controller module, telemetry and
instrumentation. They were also
responsible for the systems tests,
integration and follow final tests.
An outreach activity was also
made. It is shown the program
management strategy, what had
worked and what not, funding
strategy and the educational benefits.
ABSTRACT
In 2000 it was created in the
Universidade Norte do Paraná, UNOPAR
University, an educational undergraduate
aerospace group called SPACE.
During
the
51st
International
Astronautical Congress in Brazil, the
participant students got in contact with
different small satellite programs from
different universities. Motivated by these
contacts they began a nanosatellite project
feasibility study.
Copyright  2002 by Fernando Stancato.
Published by the American Institute of
Aeronautics and Astronautics, Inc., with
permission. Released to IAF/IAA/AIAA to
publish in all forms.
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The launch is scheduled in the end of
2002
this kind of activities is taken in all the
continents. It is a consensus that university
small satellites programs give invaluable
educational benefits, providing the
students an excellent opportunity to put in
practice their knowledge (STANCATO,
2001)
With these objectives the SPACE
began a nanosatellite project: UNOSAT –
Undergraduate University Orbital Student
Satellite.
It is the first Brazilian university
satellite and represented an extremely
challenging project as the teacher’s team
had small experience in space projects,
very small budget and two-year time frame
from the concept to launch.
The results of the program proved that
using some managing project skills the
team managed to complete all the project
phases and the benefits in education were
accomplished.
INTRODUCTION
In the beginning of 2000 it was
created a group called SPACE – Sistema
de Pesquisa Aerospacial Científica
Educativa – with the objective to make the
undergraduate students put in practice their
knowledge in the project, construction,
tests and operation of aerospace projects,
providing an hands-on experience.
The group was formed within the
Universidade Norte do Paraná – UNOPAR
University with students and teachers from
the Telecommunications and Computing
engineering.
Although the university began its
activities in 1996 and the engineering
courses in 1998, the group had a
tremendous growth after its formation.
HISTORY
The idea to begin a small university
satellite came when a team of one teacher
and three students went to the 51st
International Astronautical Congress in
2000 at Rio de Janeiro.
The students got in contact with small
satellites projects been carried in some
universities. One of them was the program
UNISAT developed at the “La Sapiensa”
Rome University. They managed to bring
two researches from that university to give
a lecture at UNOPAR University in
Londrina.
It was known that it was been
prepared the third qualification flight of the
Brazilian launcher VLS – Satellite Launch
Vehicle. Contacts were done with the
officials of the program to see the
possibilities of having a piggyback launch
Figure 1- The SPACE team in the end of
2001.
Educational small satellites programs
are not new. The first ones can be traced
back in 1980s. The Utah State University
did its 15th Annual Small Satellite
Conference last year.
A review of Micro/Nanosatellite
programs was presented (FARROW, 2001)
in the last IAF conference stating that at
least 10 nanosatellites projects was under
development for launch by late 2001. It
presents a 35-paper list that shows how
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oportunity.
Figure - 3- UNOSAT inside the SATEC.
undergraduate students, no one cursing
more than the third engineering year, a
straight project had to be elaborated.
For the engineering team, the most
important information was how some
internal parameters was changing, so it
was decided that the nanosatellite would
send in packet transmission some hardware
telemetry.
Many amateur satellites also send
some vocal messages. The students
decided that something similar would be
amazing.
The SATEC orbital information
became important when the team got the
new that the UNOSAT would have a joint
flight. The SATEC and UNOSAT will
have a circular orbit with the altitude of
700 Km and 15o of inclination. It will roll
at 170 rpm on the z-axis and will have no
attitude control. In the first days the
UNOSAT
solar
panels
will
be
perpendicular to the solar radiation but
three months later will receive no
radiation. As the team decided for a oneyear orbit life, an energy manager module
had to be developed.
The satellite would have three
transmitting operational modes: high,
medium and low rate. It would turn off
Figure 2- The VLS-1 payload area.
In the beginning of 2001 came the
positive answer. As one INPE satellite –
SATEC- was already assigned to this
flight; there was no space for a separate
satelization of both satellites. Studies
began how to make possible the flight. As
there was some internal space available
inside the SATEC then came the solution
to put the UNOSAT inside the SATEC.
The SATEC team reserved an area in the
sides of SATEC to put the UNOSAT solar
panels. After some discussions and
different antenna locations, it was found
that the best possible option was to use a
monopole antenna in the top of the
SATEC. In this way the UNOSAT would
be completely independent from the
INPE’s satellite.
MISSION
As the team had small time and
experience to prepare the satellite, the
simplest design was chosen. As the main
objective of the project was educational
and the working team was to be
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also the equipments and enter in the
“hibernation” mode when it passes in the
winter and summer solstice.
SOLAR PANNELS
In the preliminary design the solar
panel was fixed in the front cover of
UNOSAT. This was done in order to make
easier for integration in whatever
configuration it would have. At the first
configuration the UNOSAT was going to
be installed in an aperture done in one side
panel of SATEC. Later as it was put inside
the SATEC, an area for the solar panels
was reserved in the lower lateral sides.
It will be 4 solar panels with the
following characteristics:
Figure 4 - The SATEC in the Earth orbit
during the year.
Table 1. Solar Panels Characteristics
Power at BOL
8W
Solar Cells
Si, 20 mm X 40 mm
Dimensions
620 mm x 100 mm
STRUCTURE
It is basically a rectangular box with
external dimensions: 400 mm wide, 250
mm high and 85 mm deep.
It weights 4.370 Kg. Since the
preliminary design it was thought to have
lateral tabs just to help attaching, as it
would not be possible to have independent
satelization. The box was done in cast
aluminum and later machined. The
structure has only one opening in the front.
It is closed by a 3 mm aluminum sheet and
fixed by sixteen 3 mm bolts.
COMUNICATIONS
It will be used a 5W output ham-radio
as the transmitter at 148.135 MHz FM
frequency. It will use a 460 mm monopole
antenna with 1,5 dB gain.
TELEMETRY MODULE
A
commercial
microcontroled
telemetry module was used to inform 5
parameters: tension on the battery pack 1,
pack 2, pack 3, and the battery and the
transmitter transistor temperature. It
outputs this information on audible FSK
Ax25 protocol.
ENERGY CONTROL
A microcontrolled module will control
the batteries charging and discharging,
transmission rate and beginning.
Three redundant methods were used
to begin the transmission: 10 minutes after
liftoff (umbilical disconnection), 1 minute
Figure 5- The UNOSAT structure and
internal components.
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after satelisation (open a circuit) or 12
hours after turning on the satellite.
It was decided to use three redundant
batteries banks: two non-space qualified
Ni-Cads (B2, B3) and one not rechargeable
Li-MnO2 (B1). Each Ni-Cads banks are
1200 A.h and the Li-MnO2 is 11 A.hs.
The level of the charge of the batteries will
set the transmission rate:
100 %
of the
best
40 %
of
the
worst
20 %
of
the
worst
10
% of
the
wors
t
High rate
Medium
Low
rate
rate
Figure 8- The battery levels that set the
transmission rates.
The microprocessor will always
measure the charge level of both batteries.
To avoid overcharging when one of the
batteries level achieves full charge it will
disconnect the solar panels from the
batteries. It will connect again when one of
them reaches 80 % of the charge. When
one of the batteries reaches 10% of the
charge the microprocessor enters in the
hibernation mode: it turns off all the
equipment, links itself to the dry batteries
bank and at each 3 hours it wakes up and
measures the batteries level. When one of
them reaches the full charge it enters in the
transmission mode again.
The high rate was calculated to mach
the solar panels energy input with the
onboard electronics and the transmitter
output in each of the first day’s orbits.
Figure. 6 – Nicad and Li-MnO2 batteries
Figure 7 – Onboard computer and its case.
Each transmission is formed by a
telemetry packet (0,3 s) plus a voice
message (10s). It was established three
transmission rates:
 High rate: 1 transmission at each 37
seconds;
 Medium rate: 1 transmission at each 94
seconds;
 Low rate: 1 transmission at each 1,5
minute.
DIGITAL VOICE PLAY/RECORDER
It was used a commercial digital voice
play/recorder that was used in mobile
phones that can record and play a 20
seconds message.
THE PROJECT MANAGEMENT
Human resources
As said before the main objective was
to give the students and teacher a hands-on
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approach on different engineering course
topics.
The project was an opportunity also to
put in practice the Project Management
procedure (PIGNOLET, 1997)
The project was divided in 8 phases:
review of the project. In that meeting the
next launch date was expected to be in July
2002.
With this date, a reschedule was done
and the project of the main energy
controller board was started. It was put a
date of the end of January 2002 to do the
integration of the system and final tests.
Fortunately that was rescheduled to
October 2002 and the launch is foreseen to
the end of the year.
 Phase A – Definition.
In this phase it was decided what to
do. It was decided the project mission and
its parts. For each part a teacher was
invited to be the manager of it. As we had
no funds it was decided the each teacher
would try to find funds for the project and
select the students to work with.
 Phase B – Planning.
It was studied a time frame of about 6
months. That was the first time frame we
had.
 Phase C - Project.
All the parts should be dimensioned
and the main parameters are calculated.
 Phase D – Construction.
 Phase E – Tests of the parts.
 Phase F – Integration.
 Phase E – Final Tests.
 Phase G – Operation.
Difficulties Found
Many was the challenges in the
UNOSAT project:
Lack of experience: Nor the teachers
or the students had experience in the space
area project. From the beginning the team
noticed that it has a completely different
approach from other common projects.
Lack of bibliography: As the students
were not from the aerospace engineering
course, it was not found any book
regarding satellite construction at the
universities in the state.
Timetable
Lack of docent staff: The course
began in 1999 and the docent team was in
formation. In the beginning of the project
there was no teacher for the antenna
project.
The phase A and B was done
simultaneously on February 6, 2001. All
the teachers (five) met and decided the
basic concept of the nanosatellite and a 6month timetable was done. It was decided
that September 5 would be the final date to
give the satellite to INPE for integration.
In fact the 6 first months were spent in
studding the shape of the antenna and
discussions with INPE team to see the
position and shape of our antenna and the
electrical interfaces between our satellite
and the solar panels, antenna and the
umbilical.
On August 1 was done the second
meeting with the INPE team in order to
decide the electrical interfaces and a
Interfaces with other institutions: As
the UNOSAT was not going to have the
antenna and the solar panels fixed in it but
in other satellite, some decisions were
difficult to take. An agreement on the
antenna position came only 11 months
after the project start.
Lack of resources: That was one of the
more difficult item found. Just after
receiving the news that it would be
possible a ride in the next VLS launch a
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cost estimation was done. Taking the
experience of other students project
(LEON, 2000), (GRAZIANI, 2000),
(HEIDT, 2000) it was decided not to use
space qualified items. Some quotation
showed that as we had no money we were
right.
From January 2002 until September
was the construction time and integration.
During this phase it was found that spare
parts is a must as components may break
or even equipments (we lost two radio
transmitters: one simply broke and the
other had a bad heat dissipation). Another
advise is to have more than one student in
each part as if they leave it will leave a
hard slot to be replaced.
In March 2002 the student working in
the more difficult and main important
component (on board computer) simply
gave up, as he could not solve some
problems is the prototype. And he did this,
three months before the first subsystem
ambient tests! Fortunately another skilled
student had joined the group on another
project and could project built and test a
new OBC in these three months!
These intercurrences left just one
month to make the control software just
before the UNOSAT- SATEC integration
and the Thermo- Vacuum tests.
Table 1 - Costs for space qualified and not
qualified items
Solar Panel
Batteries
Space
Not
Space
Qualified
Qualified
(US$)
(US$)
18.000
430
8.000
92
The problem began when we
presented the UNOSAT proposed costs of
US$ 8.000 at the university. The answer
came in a very polite way that the
university could not afford that expenses
(specially that the investment would be
only on no recoverable items!)
From March 2001 until May 2002 all
the tentative to seek sponsors were in vain.
All the telecom companies that operate in
the state and two satellite operators were
asked and a negative answer was gotten. It
was even tried to have a broadcast radio
sponsorship making a competition on their
listeners to put their “voice in the space”.
The students went is trade show to sell
“put your name in Space” as who would
give a donation would have his name
written inside the UNOSAT.
In June 2002 the university finally
recognized the immeasurable value of the
opportunity and that made it possible to
buy all the needed components.
BENEFITS
Many benefits came to the students:
Academic
They had an opportunity to put in
practice many subjects they had in the
university. There was also the motivation
factor, as there was an immediate purpose
for their studies.
Lack of time: During the first year,
while some members were looking for
sponsorship others were beginning the
project of different parts. Some hardware
tests were done as the use of a telemetry
module, transmitter and receiver.
Figure 9 – Part of the UNOSAT team.
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Responsibility
Although made by students it had the
quality enough to pass in the tests.
Research activities in the university
usually is linked to a very comfortable
time schedule. As usually there is not a
deadline to finish the work and there is
also the possibility to postpone the date,
there is not much need on time
administration. That was not the case with
this project. Since the beginning, the top
management priority was not to delay the
delivery of the satellite as we were taken a
free ride.
That caused the ambient to be very
stressed as the team had to have always an
emergence plan in case the launch would
be eminent. That led to an easily possible
scaled down project.
Another good point was to always
have a shorter schedule than needed. It was
always put for the team a deadline some
weeks before the real date. As students do
not have much planning experience, that
strategy permitted them to better finish
some points that were under planned. It
was noticed that by the end of the project
most of the students had learned that in
engineering “ the best is the good in time”.
Teamwork
As always happen in high-stressed
teams
some
divergence
occurred,
especially at the end of the phases. But the
students overcame that with personal
agreements and mutual clear friendly
corrections.
International Experience
All
the
students
had
some
international contact experience both
indirect and direct experience as in two
consecutive years two student participated
in a UN Congress giving lectures about the
UNOSAT project.
Reliability
The students also learned to think that
it is better a simple design that you have
confidence that will work than a very
complex and beautiful project that may
fail. As a satellite is something that must
work for the first time, this led the students
to make a good review of what worked and
what not and be conservative in the design
using redundancy in critical parts.
Figure 10 – One student gave a lecture
in one UN space congress about the
UNOSAT in 2001.
High Quality
The evaluative reviews with both
teams of the launcher and the SATEC
satellite team were an excellent class of the
high quality needed for the space projects.
8
Workshop Brasileiro em Educação para o
Espaço. São José dos Campos, 1997.
Farrow
et
Al.
Micro/Nanosat
Development Programs for Partnership
Among Universities, Govenment and
Industry: Benefits and Difficulties
Encountered. IAF-01-P.2.08. Toulouse,
2001.
Stancato
et
Al.
SPACE
a
multidisciplinary Hands- On Activity.
IAF-01-P.1.08. Toulose, 2001.
Figure 11 - ...and another in 2002.
CONCLUSION
It could be seen that despite a
mountain of difficulties, a motivated team
can
overcome
them
with
some
management criteria and a lot of a work.
The students participating in a handson project incorporate inherent space
project virtues: reliability, high quality,
teamwork, time and resources management
and international experience.
REFERENCES
P. DeLeon et al. Development of
Educational Microsatellites in Argentina.
IAF-00- P.1.03. Rio de Janeiro, 2000.
H. Hiedt et al. Cubesat: a new
generation of Picosatellite for Education
and
Industry
Low-Cost
Space
Experimentation. Paper SSC00-V-5B
presented at 13th Annual Small Satellite
Conference, USU, 2000.
F. Graziani et Al. UNISAT Program: a
University Tool for Space Education. IAF00-P.2.07. Rio de Janeiro, 2000.
G. Pignolet et Al. Conceitos em
Projetos para Educação Espacial. 1o
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