Projects
Posted on March 14th, 2013. Updated on May 30th, 2017 by Renato Alves Borges

Free counters!

Analysis of the impact of the use of multiple constellation, GPS and GLONASS, for PPP in the region of Brasilia (UnB/Brazil and ICTP/Italy MoU 2016)

The main scientific aspect of this cooperation is to assess the impact of using both GPS and GLONASS constellations instead of stand-alone (GPS or GLONASS) solution for Precise Positioning around Brasilia with data extracted from the GNSS receiver of the One-Way Station (OWS) MS GLONASS, «Sazhen-TM-BIS» installed at University of Brasilia. This region is strongly affected by the Ionospheric Equatorial Anomaly (IEA) that implies a highly variable ionosphere. The particular condition of the ionosphere in that geographical area will be investigated using Total Electron Content (TEC) data extracted from the GNSS receiver that is a component of the «Sazhen-TM-BIS» station, installed at the UnB. The ionosphere is a major source of error when transmitting radio-wave signal from satellite to Earth. At low latitudes the occurrence of plasma irregularities is frequent and is reflected in large TEC rate of change (ROT) and scintillations. Most of the strongest irregularities occur in the post-sunset period of the equinoctial months during high solar activity. Being located in the equatorial area, the GNSS receiver in the region of Brasilia is expected to experience different kind of disturbances which can cause loss of lock of the satellite signals. Under these conditions the use of multi-constellation GNSS could become necessary.

Situation: Ongoing
Team:
Renato Alves Borges (UnB), Arthur Amaral Ferreira (UnB), Geovany Araújo Borges (UnB), Claudia Paparini (ICTP), Xurxo Otero Villamide (ICTP), Sandro Maria Radicella (ICTP), Anton Kashcheyev (ICTP), Bruno Nava (ICTP).
Coordinators:
Renato A. Borges (UnB/Brazil) and Sandro M. Radicella (ICTP/Italy)

Sensory platform for physiological measures in suborbital flight (Call of AEB Microgravidade 5AO/2015)

The proposed experiment aims to conduct a series of physiological measurements on a spaceman during flight in microgravity. The platform will be equipped with inertial sensors and will record all measured data in order to perform a post-flight analysis the physiological data at different parts of the trajectory. The set of devices that provides physiological measurements consists of electromyography, which records electrical activity of the muscles and an electrocardiograph, which records the electrical activity of the heart muscle. The basic accelerometer and temperature sensors are available in multiple devices. The acquisition of electromyographic signals will be made in two types of muscles: voluntarily and involuntarily activated. The goal is to study electromyography parameters such as activation level, frequency, etc. in such muscles. The electrocardiograph will be used for observation of cardiac parameters (eg heart rate, waveform) during all stages of the flight. Response mechanisms of the nervous system and cardiovascular could help the planning of strategies for addressing the negative effects of exposure to microgravity. The proposed experiment aims to monitor and investigate the psychophysiological aspects related to exposure to microgravity through the collection and analysis of indexes of heart rate variability and application of self-administered questionnaires to measure stress and anxiety. The platform is also equipped with a actigraphy module that based on accelerometer data from three axes, installed near the handle, aims to detect possible changes in sleep and circadian rhythm related to the extreme conditions faced by the spaceman during the suborbital flight. The experiment will collect data before, during and after the flight for subsequent analysis. The use of actigraphy in aerospace environments proves to be relevant for possible sleep disorders which may cause motor and cognitive disabilities, among others, during the mission.

Some technical information about the flight can be seen in the figure bellow.



Situation: Ongoing.
Team:
 Renato Alves Borges (UnB), Simone Battistini (UnB), Chantal Cappelletti (UnB), Antônio Padilha de Lanari Bó (UnB), Fabiano Araújo Soares (UnB), Marina Andrade Lucena Holanda (UnB), Alex Kraus de Castro (UnB),  Lucas de Levy Oliveira (UnB), Marina Carvalho Craveiro Moreira (UnB),  José Edil Guimarães de Medeiros (UnB),  Sandro Augusto Pavlik Haddad (UnB), Ione Alexandre Araújo (EMPSJ), Sérgio Ribeiro Augusto (IMT), Rafael Corsi Ferrão (IMT), Márcio Mathias (IMT), Vanderlei C. Parro (IMT), Leonardo Pinheiro (IMT), Alessandra Dutra Pinheiro (IMT), Wânderson de Oliveira Assis (IMT), Salomão Choueri Júnior (ETEC), Eduardo Cesar Alves Cruz (ETEC),  Cristopher Akira França Maekawa (ETEC), Matheus Gabriel da Silva (ETEC), Otávio Franco Alves Cruz (ETEC), Marco Tulio e Melo (UFMG), Daniela Ota Hisayasu Suzuki (UFSC), Bárbara Ogliari Martins Taques (IFSC).
Coordinators: 
Renato Alves Borges (UnB);
 Sérgio Ribeiro Augusto (IMT);
Daniela Ota Hisayasu Suzuki (UFSC);
Ione Alexandre Araújo (EMPSJ);
Salomão Choueri Júnior (ETEC);
Bárbara Ogliari Martins Taques (IFSC).
This system, projected by the open joint-stock corporation Research and Production Corporation - Precision Systems and Instruments, is designed to enhance the quality of navigation support of the global navigation satellite system GLONASS users in the latin-american region. Further, the data collected at the Optical Laser Station can be used for research purposes by the University of Brasilia, as for example experimental validation of research conducted at the Laboratory of Aerospace Science and Innovation and Laboratory of Automation and Robotics. 
The Optical Laser Station is able to: 
- measure distances to geodetic and navigational spacecrafts equipped with laser retroreflector systems; 
- measure angular coordinates and photometric characteristics of other spacecrafts and space debris objects observed in the reflected sunlight. 

On the basis of these measurements the following goals can be achieved: 
- precision control of the orbital parameters of the GLONASS system spacecrafts; 
- precision control of the ephemeris data transmitted in the navigational signals of the system; 
- construction and support of the State Geocentric Coordinate System and its interconnections with the International Terrestrial Reference System; 
- calibration of the measurements produced by the unidirectional radio ground stations of the GLONASS system. 

Research opportunities include Brazilian participation in the projects of the International Laser Ranging Service, observations of national spacecrafts, besides others. 
Some technical information can be seen bellow: 


Russia and Brazil space cooperation in the news: 
  • ВЕСТИ Россия
  • Portal Brasil
  • AEB - Brazilian Space Agency
  • Correio Braziliense

  • Situation: Ongoing. 
    ILRS info: Site code BRAL, Station # 7407, DOMES# 48081S001, 15.7731 S, 132.1347 W
    Brazilian Coordinators:
    Geovany Borges, Renato Borges and Ícaro dos Santos.

    Robust Methods of Analysis, Control and Filtering Applied to Systems with Vibrations and Flexible Structures - FAPDF 05/2013
    Posted on March 06th, 2014. Updated on March 06th, 2014 by Renato Alves Borges

    The objective of this research project is to investigate, develop and implement algorithms in an experimental platform for analysis, control and filtering of dynamic systems with vibrations. The central line of investigation is in the area of robust control of uncertain systems with possible applications in the context of aerospace systems. From the theoretical point of view, the methodology applied is based on the construction of Lyapunov functions which result in conditions of analysis and synthesis described primarily in terms of linear or bilinear matrix inequalities. From the standpoint of physical implementation, the project includes the purchase and installation of an experimental platform for translational movement of a rigid body, with flexible coupling, air dumping system and simulator of viscous damping. In this context, problems such as H-2 and H-infinity robust filters, Kalman filtering, finite time stability, synthesis of robust PID controllers, state feedback controllers, saturation of signals, sensor failure, among others, are considered with a view to implementing in the platform, and possibly in other physical system in the aerospace context.

    Situation: Ongoing.
    Team:
    Renato Alves Borges, João Yoshiyuki Ishihara, Alex da Rosa, Hugo Tadashi Muniz Kussaba, Simone Battistini, Chantal Cappelletti, Jorge Luiz Ferreira da Silva Junior and Renata Cristina Moura Chupel.
    Coordinator:
    Renato Alves Borges.

    Development of CanSats with Cross Communication for Terrestrial Imaging - CNPq Universal 14/2013
    Posted on October 28th, 2013. Updated on February 24th, 2014 by Renato Alves Borges

    This project considers the development of a research platform for suborbital flight called CanSat. The goal of this project is to construct two CanSats for terrestrial imaging, test the concept of communication in space (space link or cross link) and study of methods of control and stability analysis of aerodynamic systems. From the theoretical point of view, the tool being used is based on the construction of Lyapunov functions which allow to obtain synthesis and analysis conditions described primarily in terms of linear matrix inequality, to be implemented and tested in flight. From the viewpoint of physical implementation, two CanSats will be mounted using COTS electronic devices available on the market. Specifically, problems as trajectory control of an autonomous glider, study of systems affected by sector non-linearities such as saturation, dead zone and truncation errors, test of electronic devices in suborbital flight, among others, will be addressed. The project is set in the context presented by the National Space Activities Program 2012-2021 (PNAE 2012-2021), aiming to investigate economical viable solutions for applications in remote sensing, test of concept of communication between satellites in space and training people for the aerospace strategic sector. 
    This project is close related with the LAICAnSat project. In fact, it will be the second mission of the LAICAnSat family, and LAICAnSat-1 will be used in the context.

    Situation: Completed. 
    Team:
    Renato Alves Borges, Chantal Cappelletti, Simone Battistini, Manuel Nascimento Dias Barcelos Júnior, Pedro Henrique Dória Nehme, Lui Txai Calvoso Habl.
    Coordinator:
    Renato Borges. 

    Attitude determination and control simulators of small satellites - Pró-Equipamentos 027/2013
    Posted on August 20th, 2013 by Renato Alves Borges

    This project seeks to modernize the infrastructure of research groups associated to the Graduate Program in Systems Engineering Electronics and Automation (PGEA) in the context of control of aerospace systems. This is a project aligned with the activities related to aerospace at the University of Brasilia, and that covers the implementation of a platform to simulate the determination and attitude control of small satellites. Specifically, the goals of this infrastructure are enabling tests and trials of: 
    1) Attitude control algorithms developed and investigated by the group of the Laboratory of Automation and Control (LARA); 
    2) Sensors and actuators used in aerospace research developed in LARA; 
    3) Electronic devices developed and investigated by the group of Electronics ENE; 
    4) Dynamic models of rotating bodies developed and investigated in LARA, like the research groups on aircraft and aerospace; 
    5) Filters and algorithms developed for the treatment of signs and investigated by the Group of Digital Signal Processing (GPDS) and LARA. 
    It will be installed: 
    1) A Helmholtz cage to simulate different magnetic fields; 
    2) An air bearing table for small satellites attitude control simulations; 
    3) A control moment gyroscope for dynamic modeling and stabilization of three-dimensional bodies in rotation. 

    Situation: Ongoing. 
    Team:
    Renato Alves Borges, Artemis Marti Ceschin, Geovany Araújo Borges, João Yoshiyuki Ishihara, Francisco Assis de Oliveira Nascimento, Eduardo Stockler Tognetti , Manuel Nascimento, Paolo Gessini, José Leonardo Ferreira.
    Coordinator:
    Renato Borges. 

    PIBIC Project 2015
    Posted on July 20th, 2015 by Renato Alves Borges

    The present Institutional Program of Scientific Initiation Scholarships (PIBIC) project is related with the investigation, development and implementation of algorithms for Global Navigation Satellite Systems (GNSS) with emphasis on the GLONASS system. The main line of research contemplated in this project concerns the analysis of data obtained in laser ranging measurements and one-way referencial station. In general, the characterization of the propagation of the radio signal from the satellites in the Brasilia region, the understanding of the measured data for precise point position and also the operation of the station represent a promising and important field in the context of Aerospace Engineering. Immediate consequences of results in this area will benefit various fields of engineering and contribute to improve GNSS services and solutions.

    Situation: Completed. 
    Team:
    Renato Borges and Iohana Gabryelle Gauna de Siqueira.
    Coordinator:
    Renato Borges. 
    Undergraduate student:
    Iohana Gabryelle Gauna de Siqueira (grant recipient). 

    LAICAnSat Project

    The LAICAnSat is the first BalloonSat project developed at the University of Brasilia. This project simulates the development of a satellite mission, qualifying equipment and human resources for more complex aerospace missions. The project's objective is to design, build and launch a near-space experimental BalloonSat with meteorology and remote sensing applications. One possible structure for the BalloonSat is the CanSat. The concept of a CanSat is to develop and launch a small satellite (the size of a soda can), simulating its major stages and subsystems. For CanSats, the launch can be also done by small rockets. A brief description of the LAICAnSat project is as follows.



    Situation: Ongoing. 
    Mission:
    Geo imaging and sensing, navigation and control, electronic devices tests. 
    Former Team (LAICAnSat-1 and LAICAnSat-2):
    Renato Borges, Chantal Cappelletti, Simone Battistini, Pedro Nehme, Rafael Dias, André Vinícius and Bruno Henrique.
    Current Team:
    Renato Borges, Chantal Cappelletti, Simone Battistini, Manuel Barcelos, Alex Kraus, Marina Andrade, Breno, Arthur, Felipe, Lucas, Raphael, Guilherme, Gabriel and Daniel.
    Principal investigator:
    Renato Borges. 
    Co-investigators:
    Chantal Cappelletti, Simone Battistini and Manuel Barcelos. 
    Subsystems:
    Subsystem Description Responsable
    Electronics
    Hardware and software implementation
    Alex, Marina
    Payload
    Camera and image processing
    Marina
    Communication
    Base station and link
    Marina
    Mechanics
    Structure, paraglide and balloon
    Breno, Arthur, Felipe, Lucas, Raphael, Guilherme, Gabriel and Daniel.

    The project is divided in two main parts: Low Altitude Part (LAP) and High Altitude Part (HAP). For the LAP there are two possibilities for launch: balloon or small rocket. Experiments conducted in the LAP include modeling and control system to maneuver the payload, using a paraglider, and guide it throw some predefined waypoints; sensing and tracking systems. For the HAP, the launch will be with balloon and the experiments include qualify COTS electronic devices; camera pointing control; geo imaging; and landing maneuver and control.
    For the LAICAnSat-1, a HAP experiment, a weather balloon will carry the payload to the edge of space. The payload has an onboard high performance camera, that will take pictures during ascend and descent. Those pictures will be used for further remote sensing applications. The embedded system also has other sensors to provide precise information about ambient temperature, pressure, humidity, UV light level, altitude, position, speed, heading, acceleration, as well as voltage, current and temperature monitors. LAICAnSat-1 is enabling low cost remote sensing and also reducing the risk of losing expensive hardware, as for example in the case of radiosondes. This project has an importance to the brazilian aerospace industry, by building an affordable near-space platform to test and qualify COTS electronic devices to be used in aerospace projects.
    For recovery of LAICAnSat-1, the base station will track it during the mission using the altitude and position signals obtained from the GPS (APRS system), pressure sensors and inertial measurement unit, which will be transmitted via radio frequency. All data collected during the ascent and descent are stored locally on SD memory cards for later analysis.
    The launch was postponed to 2014 due to the change on the parachute structure and weather conditions. The specific date and time will be determined soon following the guidance of the First Integrated Center of Air Defense and Air Traffic Control, CINDACTA-1.

    Paraglider test (September 15th at Mergulho no Céu, Anápolis-GO):
    The weight and the structure of LAICAnSat-1 was reproduzed using a test load to minimize injury in the case of a opening failure of the paraglider. A GoPro Hero3 camera was attached to record the behavior of the paraglider. The test load was launched by A. R. Durigon, a professional parachutist, at an altitude of 1800 feet. The parachute has opened and then a twist occured but it has dissolved in the following instants. Shortly after, the system goes into a loop, falling very close to where we were watching. An unbalanced test load may have led to the loop descent. For a reason still unknown, the GoPro camera stopped recording in the middle of the fall. The videos can be seen bellow.

    Parachutist camera: 
    Test load camera: 

    Square parachute test (February 23rd at RC aeromodelling field, Brasília-DF):
    A new square parachute for the LAICAnSat project was tested using a RC car+parachute. This new structure (see the pictures bellow) will be used to test control algorithms, the communication system and some electronics of the LAICAnSat-1.
                          

    After fixing some details of positioning electronics and engine, a first flight was done but for some reason the radio has not recorded the settings of the RC parachute and the commands were in reversed direction leading to a fall. The video can be seen bellow.

    First flight (commands in reversed direction) : 
    Due to the fall, one of the aluminum tubes ended up breaking. After a temporary fix, a second flight was perfomed with success, as shown in the video bellow.

    Second flight (all set and success): 
    The flights were performed by Carlo Júnior, a professional RC aeromodel pilot, with the help of the pilots Filemon and Márcio. The LAICAnSat team thank you very much for your support! The RC car+parachute was developed by James from Curitiba-PR (email: sm-carrinhoparaglider AT hotmail.com).

    GoPro camera new video (March 01st at RC aeromodelling field, Brasília-DF):
    A new test of GoPro camera was performed last saturday, March 01st, 2014, at RC aeromodelling field, Brasília-DF! The goal is to start evaluating some image processing algorithms with the videos seen bellow. For this, the LAICAnSat team is having the help of Professor Mylène C. Q. de Farias, a specialist on image processing from the Electrical Engineering Department of UnB.

    GoPro video 1: 

    GoPro video 2: 

    APRS system tested (March 29th at RC aeromodelling field, Brasília-DF):
    The APRS system was tested on March 29th, 2014, at RC aeromodelling field, Brasília-DF! The trajectory can be seen in the figure bellow:

    LAICAnSat first flight was a success! (May 02nd at Padre Bernardo - GO):
    It is a great pleasure to announce that the first flight of LAICAnSat-1 was considered a complete success! I would like to thank very much all LAICAnSat members and our partner in this project The MUTUM Radio Expedition Group.  One of the picture took from the Stratosphere can be seen bellow:

    The LAICAnSat UnB is a member of Amateur Radio High Altitude Ballooning - ARHAB, and the mission LAICAnSat-1 is listed there. It is my pleasure to state that LAICAnSat-1 established a new record at the ARHAB community concerning the shortest great circle distance measure from release to the touchdown position. One can check at ARHAB website in the records menu, distance submenu, that we are ranked number 6 over 434 missions announced there!

    LAICAnSat-1 Overview:
    Mission:
    Geo imaging and sensing.
    Launch site:
    Padre Bernardo, GO, Brazil, -15.1161, -48.1964, S15° 6' 58", W48° 11' 47".
    For the launch site map click here!
    Balloon type:
    Latex, 1200g, Helium.
    Tracking system:
    APRS 145.570Mhz. For the balloon trajectory click here!
    After Flight Report (ARHAB): LAICAnSat-1 Recovered!
     
     Stage  Time  Altitude  Latitude, Longitude  Notes
     Launch or First  12:15:08 UTC  2,208 ft. 0.67 Km  -15.11500, -48.19700
    GH54VV
     Distance from Launch Ascent/Descent Rates
     Burst or Max Altitude:  13:32:05 UTC 89,187 ft.
    27.18 Km
     -15.16417, -48.19883
    GH54VU
     3.4 Mi / 5.5 Km 
    20.68 km/h
     Touchdown or Last:  15:19:08 UTC  2,208 ft. 0.67 Km  -15.19267, -48.15783
    GH54WT
     6 Mi / 9.6 Km 
    14.87 km/h


    LAICAnSat-1 Mission:


    LAICAnSat-1 in the news:
  • DFTV - TV Globo
  • UnB Web Portal
  • AEB - Brazilian Space Agency
  • Jornal Meio Ambiente
  • Brazil Government Web Portal
  • Brazilian Space Blog

  • LAICAnSat second flight was a success! This time it was carrying the Brazuca Ball (May 24th at Padre Bernardo - GO):
    It is a great pleasure to announce that LAICAnSat-2 flight was considered a complete success! After three trials it was finally recovered on May 31st with the help of a team of Brazilian Fireman. Once again I would like to thank very much all LAICAnSat members and our partner in this project The MUTUM Radio Expedition Group. Further, I would like to say a special thanks to Lieutenant Wilder from CINDACTA-1 that helped us with all flight procedure and authorization (NOTAM), and also the firefighters team from the 10a CIBM of Planaltina de Goiás, Lieutenant Cordeiro, Sergeant Ferreira, Private Gilvan and Corporal Leonel who were responsible for the rescue of LAICAnSat-2. One of the picture took from the Stratosphere can be seen bellow. 


    LAICAnSat-2 Overview:
    Mission:
    Geo imaging, sensoring and brazuca ball.
    Launch site:
    Padre Bernardo, GO, Brazil, -15.0628, -48.2842, S15° 3' 46", W48° 17' 3".
    For the launch site map click here!
    Balloon type:
    Latex, 1200g, Helium.
    Tracking system:
    APRS 145.570Mhz. For the balloon trajectory click here!
    After Flight Report (ARHAB): LAICAnSat-2 Recovered!

    Stage  Time  Altitude  Latitude, Longitude  Notes
     Launch or First  13:47:34 UTC  2,129 ft.
    0.65 Km
     -15.05550, -48.29883
    GH54UW
     Distance from Launch Ascent/Descent Rates
     Burst or Max Altitude:  17:42:31 UTC 91,917 ft. 28.02 Km  -15.05900, -48.11983
    GH54WW
     11.9 Mi / 19.2 Km 
    6.99 km/h
     Touchdown or Last:  19:39:33 UTC  2,775 ft. 0.85 Km  -15.04500, -48.03367
    GH54XW
     17.7 Mi / 28.5 Km 
    13.94 km/h


    LAICAnSat-2 Mission:


    LAICAnSat-2 in the news:   

  • Jornal Nacional - TV Globo
  • LAICAnSat presentation:   

  • Dept. Eng. Mecânica UFMG - 16/06/15 (slides in portuguese here).

  • Verification of Fault-Tolerant Embedded Systems with Reconfigurable Self-Healing Hardware using a Correct-by-Construction Design Flow (Call of Innovation Projects CISB 1/2014)
    Posted on December 23rd, 2014. Renato Alves Borges

    The main goal of this project is to use a correct-by-construction design flow in order to perform the design and verification of fault-tolerant embedded systems with reconfigurable self-healing hardware. In particular, two main applications will be used. The first one is a HAP (High Altitude Platform) and the second one is a controlled parachute guidance system for delivering payloads. The expected benefits of this proposal are increased productivity and lower development costs in the design process of more reliable embedded systems with real time and safety-critical applications, especially for industrial users in the avionics domain. A design flow that enables a rapid design of a system by assembling and configuring platform components can save the designer from performing extensive verification efforts and support time-to-market requirements. The applications in this proposal have an importance to the Brazilian aerospace industry, by building an affordable near-space platform to test and qualify Commercial-Off-The-Shelf (COTS) electronic devices such as the Automatic Packet Reporting System (APRS) used for tracking. Since the success of the mission and possibly the rescue of the payload depends on the proper functioning of the electronic equipment, it will be very important to board fault-tolerant systems with re-configurable hardware as described in this proposal.

    Situation: Completed. 
    Team:
    Gilmar Silva Beserra (UnB), Ingo Sander (KTH - Sweden), José Camargo da Costa (UnB), Daniel M. Muñoz Arboleda (UnB), Renato Alves Borges (UnB), Simone Battistini (UnB), Diana Göhringer (RUB - Germany), SAAB Group (www.saabgroup.com) and DFChip (www.dfchip.com).
    Coordinator:
    Gilmar Silva Beserra. 

    Design and Manufacture of a Propulsion System that Meets the Requirements of SARA Reentry System Platform Using Hybrid Propellants - AEB Uniespaço AO 01/2013
    Posted on March 06th, 2014. Updated on March 06th, 2014 by Renato Alves Borges

    The propulsive systems based on hybrid propellants due to their comparative advantages to systems with solid and liquid propellants are becoming an important technology option for many space applications. Noteworthy are the equivalent to other chemical technologies, low emissions, operational safety and competitiveness in technological performance levels and reduced costs. Thus, the hybrid propellant rocket engines currently has been studied in several countries, including those who already have technology maturation in liquid and solid engines such as United States, Russia and China, for example. In Brazil, the Hybrid Propulsion Team at the University of Brasilia (HPT-UnB) studies hybrid technology since the early 2000s and it has designed and built a successful sounding rocket 1500N (Uniespaço 2004) thus demonstrating an important step towards the nationalization of the technology and staff training (undergraduate, masters and doctoral). A further important step in the field of hybrid technology was the work done with thrust modulation (Uniespaço 2007) where the group developed a hybrid engine in laboratory scale with variable thrust. Regarding the hybrid propulsion, the HPT-UnB has reached level three of technological maturity (TRL=3). The development of an engine capable of performing the induction of reentry for the SARA platform (IAE-Brazil) is a relevant technological demand for Brazilian space program (PNAE). Theoretically, the problem was studied by HPT-UnB, based on a hybrid rocket motor propellants. The primary characteristics of this engine, able to fulfill the mission, were obtained by multivariable and multidisciplinary optimization code via genetic algorithms. In general, this proposal (Phases 1 and 2) aims to validate the propulsion system (reentry engine for SARA platform) in the laboratory, improving the level of technological maturity (advance to TRL=4). To do so, the prototype should fulfill the main criteria of the mission, namely to generate a given level of thrust to ensure the platform speed variation estimated for performing the reentry maneuver. The main components of the system are mostly the type COTS (commercial off-the-shelf).

    Situation: Completed. 
    Team:
    Olexiy Shynkarenko, Paolo Gessini, Manuel Nascimento Dias Barcelos Júnior, Simone Battistini, Renato Alves Borges, Artur Elias de Morais Bertoldi, Erlan Rodrigo de Souza Cassiano, Igor Seuti Kinoshita Ishioka, Gabriel Santos da Costa Pinto, Ramon Bevelaqua.
    Coordinator:
    Olexiy Shynkarenko. 

    Modeling, Analysis and Robust Control of Inverted Pendulum with Reaction Wheel and DC Motor - FUB/UnB/DPP 02/2013
    Posted on October 23rd, 2013 by Renato Alves Borges

    This research project aims to investigate, develop and implement algorithms for experimental platform for analysis and control of inverted pendulum with reaction wheel and DC motor. The central line of investigation is analysis, filtering and robust control of dynamical systems with structure constraints or affected by exogenous noise. From the theoretical point of view , the methodology is based on the construction of Lyapunov functions which allow to obtain synthesis and analysis conditions described primarily in terms of linear matrix inequality, or bilinear matrix inequalities. In the context of practical implementation, the project includes the purchase and installation of an experimental platform with three different configurations of the inverted pendulum: simple inverted pendulum with reaction wheel, double inverted pendulum (PENDUBOT), and rotary inverted pendulum (Furuta Pendulum) with also a DC motor to test the algorithms developed and investigated. Within this context, problems such as robust H-2 and H- infinity filters, control of dynamic systems in finite time, robust synthesis of PID controllers, state feedback controllers, saturation of signals, among others, are investigated in view of the implementation at the platform to be installed.

    Situation: Completed. 
    Team:
    Renato Alves Borges, Eduardo Stockler Tognetti and Taís Calliero Tognetti.
    Coordinator:
    Renato Borges. 

    PIBIC Project 2014
    Posted on January 24th, 2015 by Renato Alves Borges

    The present Institutional Program of Scientific Initiation Scholarships (PIBIC) project is related with the investigation, development and implementation of algorithms for the experimental platform of inverted pendulum with reaction wheel and DC motor. The central line of investigation is robust control of dynamical systems with structure constraints or affected by exogenous noise. The inverted pendulum with reaction wheel, the object of study of this project, consists of a simple pendulum parallel to an inertial wheel, concentrated parameter, controlled by torque. The system of motion (pendulum + wheel) can be analyzed and controlled using the coupling torque between the reaction wheel, actuated by a 24V DC motor with a permanent magnet, and the rod pendulum. This is a model that allows the simulation of the behavior of various physical systems of interest such as a rocket in third stage, bipedal locomotion, among others, what motivates the research. Probably the pendulum is one of the most important examples in the area systems of dynamic control systems, and perhaps the mechanical system more studied since Galileo's time.

    Situation: Completed. For the abstract click here!  
    Team:
    Renato Borges and Pedro Henrique Moreira da Fonseca.
    Coordinator:
    Renato Borges. 
    Undergraduate student:
    Pedro Henrique Moreira da Fonseca (grant recipient). 

    PIBIC Project 2013
    Posted on August 20th, 2013 by Renato Alves Borges

    The present Institutional Program of Scientific Initiation Scholarships (PIBIC) project is related with filter design for unknown nonlinear dynamic systems. Specifically, it investigates the problem of robust filter design of continuous-time systems in the context of absolute stability. The filter is designed in order to guarantee that the estimation error system is absolute stable with respect to sector bounded nonlinearities. The system is considered uncertain with the parameters modeled within a unit simplex. The design conditions obtained by means of a Lur'e-Persidkii Lyapunov function are expressed as linear matrix inequalities. The absolute stability is assessed by using polynomial relaxations with arbitrary degree. The filter is obtained by the solution of an optimization problem.

    Situation: Completed.  For the abstract check here!
    Team:
    Renato Borges and Renata Cristina Moura Chupel.
    Coordinator:
    Renato Borges. 
    Undergraduate student:
    Renata Cristina Moura Chupel (grant recipient). 

    Quanser IP02 Project
    Posted on March 28th, 2013. Updated on February 12th, 2014 by Renato Alves Borges

    This research project aims to investigate and propose methods for synthesis of controllers for linear time-invariant systems subject to parametric uncertainties to ensure asymptotic stability of the closed-loop system. The tools will be tested in the Quanser plataform IP02. The approach used is based on Lyapunov functions in order to obtain numerically tractable convex optimization methods.

    Situation: Completed. 
    Team:
    Renato Borges, Wattyllas dos Reis and Isaac Ambrósio da Silva.
    Coordinator:
    Renato Borges. 
    Undergraduate student:
    Wattyllas dos Reis and Isaac Ambrósio da Silva (grant recipients). 

    Highly Interacting Ambient Systems - PROBRAL 2012
    Posted on August 20th, 2013. Updated on February 12th, 2014 by Renato Alves Borges

    In Ambient Systems an increasing trend towards networked, especially wireless networked systems is observed. Wireless networks are applied to facilitate and to increase the information exchange among the different nodes of the ambient system network. This holds especially true when moving nodes are used. Interesting applications like Robotics and Ambient Assisted Living (AAL) which are treated in this project will profit from this development if the two major challenges can be met: compensation of network induced effects and usage of limited energy resources. The scientific goals of this project are: 
    1. Answering existing theoretical questions; 
    2. Revealing and bridging gaps between theory and praxis. 
    The following problems are considered by studying humanoid as well as mobile robots and automated office buildings available at the research partner institutes in Germany and Brazil. Communication between mobile systems puts high demands on transmission quality, especially in control systems. A desired system performance is maintained by analysis of network effects (delays, losses) and selection of appropriate control structures. This requires deep theoretical research to improve the quality of service, e.g. in agricultural engineering communication is an emerging topic of research. State-of-the-art agricultural equipment relies a lot on complex data-exchange between tractors and accessory equipment to enable proper control of the harvesting-process. In a sensor network the placement of each component in a well-functioning compound is a crucial point. Important factors are the sensor coverage rate and energy efficient arrangement of energy harvesting sensors in an indoor environment. Generic methods are studied to allow an optimal arrangement. In Robotics, the focus of research will be to shift the complexity of robots into the robot environment while not sacrificing but rather increasing the level of reliability and safety of the whole system. The compound of robot and environment represents a highly interactive ambient system.

    Situation: Completed. 
    Brazilian Team:
    Adolfo Bauchspiess, Geovany Araújo Borges, João Yoshiyuki Ishihara, Alex da Rosa, Antônio Padilha Lanari Bó, Renato Alves Borges, José Alfredo Ruiz Vargas.
    German Team:
    Lothar Litz, Thorsten Rodner, Stefan Schneider, Konstantin Machleidt, Jie Zhao, Karsten Berns, Philipp Bauer, Jochen Hirth, Michael Arndt. 
    Brazilian Coordinator:
    Adolfo Bauchspiess. 
    German Coordinator:
    Lothar Litz. 
    Graduate students:
    Luis Felipe da Cruz Figueiredo, Roberto de Souza Baptista, Henrique Marra Menegaz. 

    PIBIC Project 2012
    Posted on March 28th, 2013. Updated on May 22nd, 2014 by Renato Alves Borges

    The present Institutional Program of Scientific Initiation Scholarships (PIBIC) project is related with control of unknown linear dynamic systems. Specifically, it investigates the problem of parameter dependent state feedback control of continuous-time systems in the context of finite time stability. The controller is designed in order to guarantee that the closed-loop system is finite time stable. The system is considered time varying with the parameters modeled within a unit simplex. The design conditions obtained by means of Lyapunov functions are expressed as linear matrix inequalities. The finite time stability is assessed by using homogeneous polynomially parameter-dependent state feedback gains with arbitrary degree. The controller is obtained by the solution of a factibility problem.

    Situation: Completed. For the abstract check here!
    Award received: Honorable Mention in the Outstanding Award of Undergraduate Research, 19th Congress of Scientific Initiation UNB and 10th Congress of Scientific Initiation of the DF. Check here the winners
    Team:
    Renato Borges and Laríssa de Paiva Silva.
    Coordinator:
    Renato Borges. 
    Undergraduate student:
    Laríssa de Paiva Silva (grant recipient).