Programação Final do 5TH European Cubesat Symposium

Olá leitor!

Recentemente postei aqui no blog (veja aqui) uma nota informando que dois grupos brasileiros que atuam na área de Cubesats participariam do importante evento “5TH European Cubesat Symposium”, marcado para acontecer de 03 a 05/06, na Real Academia Militar de Bruxelas, na Bélgica.

Acontece que após contato com um leitor anônimo (ao qual agradeço), que creio seja ligado a um dos grupos brasileiros participantes do simpósio, o mesmo me enviou a programação final do evento (veja aqui) onde pude constatar que a participação brasileira será maior do que a divulgada por mim anteriormente.

Veja abaixo essa participação como descrita na programação do evento.

Duda Falcão

PALESTRAS (APRESENTAÇÕES)

NANOSATC-BR1, MECHANICAL ANALYSIS, 

ONGOING AND FUTURE DEVELOPMENTS

R.Z.G. Bohrer1, I.C. Silveira2 and N. Schuch2

1 - Technological Institute of Aeronautics (ITA), Brazil

2 - Southern Regional Space Research Center – CRS/CCR/INPE – MCTI, in collaboration with the Santa Maria Space Science Laboratory – LACESM/CT – UFSM, Brazil

The Brazilian NANOSATC-BR CubeSat Development Program is based on the worldwide CubeSat concept with emphasis on capacity building of the new generation of aerospace professionals through every step of a real space project, from planning to development, implementation and operation.

As a first project, NANOSATC-BR1 will monitor the space weather and atmospheric anomalies over the Brazilian territory, such as the geomagnetic field disturbances and their effects on the region known as the South Atlantic Magnetic Anomaly (SAMA). Aiming for a quick development, the first CubeSat as well as the ground station were purchased from Innovative Solutions In Space (ISIS). They are used as model for reverse engineering and training of students involved in the Project.

This paper will present the current stage of the NANOSATC-BR1 satellite, the scheme and the students’ involvement in the project, focusing on studies and analysis performed on the mechanical platform. Analysis results will be presented and discussed, based on the Indian Polar Satellite Launch Vehicle (PSLV) and mechanical project requirements.

In conclusion, a summary of the present studies and proposals for a new 1U CubeSat platform is presented, developed to support the subsystems of future academic space projects, as well as the present developments of the NANOSATC-BR2, the second nanosatellite project.

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LOW-DRAG EXPANDABLE SOLAR PANEL  TO

PROVIDE EXTRA POWER FOR CUBESATS

C.S. Cordeiro1, R.A. de Carvalho1and F. Pacholke2

1 - Instituto Federal Fluminense, Campos dos Goytacazes, Brazil

2 - LSI-Tec - Associação do Laboratório de Sistemas Integráveis Tecnológico, São Paulo, Brazil

The proposed paper presents the design of an expandable solar panel fixed in the middle of the rear face of a CubeSat and in the longitudinal direction of flight with the objective to provide extra power without increasing the drag. This would be ideal for CubeSats in very low-Earth orbits, like those in the QB50 mission. Due to be expandable, it is split into segments that are connected by hinges. The first segment, which is connected directly to the satellite, has one solar cell on each side and its length is half of the rear face of the satellite. The other segments have the length of the rear face of the satellite, which have two solar cells on each side.

The hinges have springs and restrictions so that the solar panel can unfold automatically. Each  segment aligns at an angle of 180⁰ to each other, and all of them are perpendicular to the rear  face of the satellite. This unfolding should occur after detumbling, so that the panel will not  increase the moment of inertia. The unfolding will begin when the synthetic wire, that holds the panel folded, is cut by the heating resistor attached to the wire.

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OPTIMIZING DATA DOWNLOAD TO A CLUSTER OF NETWORKED

GROUND STATIONS: A MODEL FOR THE QB50 PROJECT

R.A. de Carvalho, C.S. Cordeiro and L.G.L. Moura

Instituto Federal Fluminense, Campos dos Goytacazes, Brazil

One of the QB50 mission challenges is to provide enough data download capabilities in order to get all (or the maximum of) scientific, telemetry, and housekeeping data supplied by all 50 satellites. Given the expected orbit inclination and altitude, regarding the concentration of ground stations, the satellites will fly over three basically different types of regions: empty, such as the oceans and the polar regions; sparse, with only a few stations; and clustered, with many stations relatively close, such as in Europe and Brazil.

In clustered regions the satellites' footprints will frequently cover more than one station, thus creating the problem of deciding how much data each station is going to download from each satellite, since their ranges overlap in some periods of the flight. This work presents an ‘orchestration’ model for optimizing the total volume of data to be transmitted to a cluster of ground stations, considering the main characteristics of the QB50 mission.

The main result of the model is to determine, for a given pass, the optimal sequence of antenna movements, with respective start and end points. The model provides an objective function that considers the quality of transmission, influenced by the view angle and distance to the orbit, and takes into account the following constraints

- overlapping of ground stations range,

- antenna movement delays and limitations,

- establishment of an equilibrium between the previous constraints and the a) data available to download and b) for each satellite, the power available for transmission.

Additionally, it is possible to prioritize the download from a given satellite to a given ground station by setting up the appropriate coefficients in the objective function.

This model is implemented by a software that compiles all the necessary information and provides functionalities for simulating different scenarios and implementing the most appropriate.

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WEB SERVICE FOR SATELLITE TRACKING AND

PREDICTION FOR THE 14-BISAT PROJECT

L.G.L. Moura, R.A. de Carvalho and C.S. Cordeiro

Instituto Federal Fluminense, Campos dos Goytacazes, Brazil

The 14-BISAT Project will be one of the first Brazilian CubeSat projects. Its main goal is educational. The 2U 14-BISAT CubeSat is part of the QB50 Project, carrying one of the standard science sensor sets. As part of the project, the 14-BISAT ground segment will involve a total of at least 12 ground stations. These stations will be distributed mostly on Brazilian  territory, while a couple of them are placed in Portugal. Coordination among them will be made from Instituto Federal Fluminense (IFF), which will host the leading ground station and the 14-BISAT team.

This paper presents a proposal to automate this coordination using web service as solution. The web service will have a satellite tracking algorithm that calculates the position of the orbiting satellites at any time and will centralize the information that will be downloaded from the satellites. Also, it will calculate where the antennas should be pointed in space to receive the satellite signals.

This algorithm is based on the SGP4 model that takes into consideration the disturbing forces constantly affecting the satellite trajectory, such as the gravitational attraction of the Sun, the Moon, and the Earth. The paper presents also the web application for satellite tracking and prediction, the satellite orbit visualization, the satellite motion controller and other functions.

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GAMANET: NETWORKING QB50 – FIRST RESULTS

P. Rodrigues1, P. Sinogas1, S. Cunha2, R.Pinho2,

C. Salotto3, A. Oliveira1, R. Mendes1

1 - TEKEVER, Lisbon, Portugal

2 - Faculty of Engineering, University of Porto, Porto, Portugal

3 - Instituto Federal Fluminense, Campos dos Goytacazes (São Paulo), Brazil

GAMANET is an ambitious endeavour in space communications being proposed within the scope of QB50. Its challenge is the creation of the largest ad-hoc communications network ever in space. Its goal is to bring the networking capability to satellite constellations. QB50 presents itself as the ideal mission to test such technologies, gathering worldwide CubeSats around a common communications platform. As GAMANET participants, QB50 CubeSat teams will have the networking resources required to send commands from ground and to receive satellite telemetry, even when their own satellites are not within range of their stations. Joining CubeSats and ground stations in a seamless communications network, the GAMANET initiative aims both to validate innovative communication technologies in space and to improve the overall QB50 communications and scientific results.

GAMANET will have two segments, connected seamlessly together: the space segment and the ground segment. Each segment will have different, though similar devices and different interfaces. GAMANET’s enabling device is GAMALINK, an advanced communications platform relying on the flexibility of Software-Defined Radio. Present on every GAMANET node, whether a CubeSat or a ground station, GAMALINK empowers the formation of mobile wireless ad-hoc networks in space, benefitting from technology that has already been vastly tested to provide connectivity in the most demanding environments on the ground. GAMALINK also delivers accurate position determination based on GPS, which provides absolute position and timing information that may be used to achieve synchronisation between satellites. Optionally, it can also include an experimental radio-based attitude determination algorithm, which may be used as an extra attitude determination sensor for improved redundancy and/or accuracy.

In this presentation, the concept and its benefits for CubeSat network and constellation missions together with the potential of the involved technologies will be further detailed. The first prototype results of GAMANET will be presented and the next steps towards validation will be described.

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POSTER

SIMULATION OF ENERGY PRODUCED BY SOLAR PANELS

TO VALIDATE THE BALANCE OF ELECTRICAL POWER IN CUBESATS

C. Toss Hoffmann1, F. Bizarria2, G. Loureiro3, D. Carrera3,

L. Costa3, E. Bürger3, M. Pereira1 and J. Bizarria4

1 - Technological Institute of Aeronautics, Brazil

2 - Institute of Aeronautics and Space, Brazil

3 - National Institute for Space Research, Brazil

4 - University of Taubaté, Brazil

CubeSats are small satellites with a cube-shaped structure that carry solar panels on their outside faces to generate the power needed in orbit for the operation of the subsystems of the CubeSat. It is therefore necessary for the electrical and electronic components of the CubeSat to be tested before operation in orbit to meet the level of reliability that is required for the

application in question.

This paper proposes a model to simulate the power produced by solar panels for testing the charge and discharge of batteries in the power supply subsystem of the CubeSat. The validation of the simulation shown in this work is performed through tests on a prototype developed for this purpose. The positive results observed in the tests suggest that the simulation is able to represent the main conditions for the production of energy by the solar panels when the CubeSat is in orbit.

Fonte: 5TH European Cubesat Symposium