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- BoaVista – Sensor Dedicado de Visão Artificial Baseado em Hardware (Re)configurávelPublication . Lima, Luís; Almeida, José; Martins, Alfredo; Silva, EduardoEste artigo aborda o projecto de um sistema de visão dedicado para robótica móvel autónoma, que beneficia das capacidades de execução paralela do hardware reconfigurável, processando em “pipeline” as imagens provenientes de um sensor de imagem CMOS de alto desempenho em simultâneo com a aquisição das mesmas. Apresentamos um sistema com a capacidade de adquirir e processar imagens com resoluções de 640x480 a uma taxa de 60 fps, baixo custo e capaz de disponibilizar para o sistema central apenas a informação pretendida extraída da imagem. Este ponto, permite libertar os recursos computacionais do robot traduzindo-se em reduções de consumo significativas e consequente aumento da autonomia energética do mesmo.
- Master's in autonomous systems: an overview of the robotics curriculum and outcomes at ISEP, PortugalPublication . Silva, Eduardo; Almeida, José; Martins, Alfredo; Baptista, João Paulo; Neves, Betina CamposRobotics research in Portugal is increasing every year, but few students embrace it as one of their first choices for study. Until recently, job offers for engineers were plentiful, and those looking for a degree in science and technology would avoid areas considered to be demanding, like robotics. At the undergraduate level, robotics programs are still competing for a place in the classical engineering graduate curricula. Innovative and dynamic Master’s programs may offer the solution to this gap. The Master’s degree in autonomous systems at the Instituto Superior de Engenharia do Porto (ISEP), Porto, Portugal, was designed to provide a solid training in robotics and has been showing interesting results, mainly due to differences in course structure and the context in which students are welcomed to study and work
- High-Accuracy Low-Cost RTK-GPS for an Unmanned Surface VehiclePublication . Matias, B.; Oliveira, H.; Almeida, José; Dias, André; Ferreira, H.; Martins, Alfredo; Silva, EduardoThis work presents a low cost RTK-GPS system for localization of unmanned surface vehicles. The system is based on the use of standard low cost L1 band receivers and in the RTKlib open source software library. Mission scenarios with multiple robotic vehicles are addressed as the ones envisioned in the ICARUS search and rescue case where the possibility of having a moving RTK base on a large USV and multiple smaller vehicles acting as rovers in a local communication network allows for local relative localization with high quality. The approach is validated in operational conditions with results presented for moving base scenario. The system was implemented in the SWIFT USV with the ROAZ autonomous surface vehicle acting as a moving base. This setup allows for the performing of a missions in a wider range of environments and applications such as precise 3D environment modeling in contained areas and multiple robot operations.
- Groundtruth system for underwater benchmarkingPublication . Martins, Alfredo; Dias, André; Silva, Hugo Miguel; Almeida, José Miguel; Gonçalves, Pedro; Lopes, Flávio; Faria, André; Ribeiro, João Pedro; Silva, EduardoIn this paper a vision based groundtruth system for underwater applications is presented. The proposed system as an external validation perception and localization mechanism for underwater trials in the INESC TEC / ISEP underwater robotics test tank. It is comprised by a stereo camera pair with external synchronization and a image processing and data recording host computer. The cameras are disposed in a rigid baseline calibrated using scenario key points. Two target detection algorithms were tested and their results are discussed. One is based on template matching techniques allowing the tracking of arbitrary targets without particular markers and the other on color segmentation with the target vehicle equipped with light markers. Also an example trajectory of a small ROV motion in the task is also presented.
- Real-Time Visual Ground-Truth System for Indoor Robotic ApplicationsPublication . Dias, André; Almeida, José Miguel; Martins, Alfredo; Silva, EduardoThe robotics community is concerned with the ability to infer and compare the results from researchers in areas such as vision perception and multi-robot cooperative behavior. To accomplish that task, this paper proposes a real-time indoor visual ground truth system capable of providing accuracy with at least more magnitude than the precision of the algorithm to be evaluated. A multi-camera architecture is proposed under the ROS (Robot Operating System) framework to estimate the 3D position of objects and the implementation and results were contextualized to the Robocup Middle Size League scenario.
- A New ROV Design: Issues on Low Drag and Mechanical SymmetryPublication . Gomes, Rui; Fraga, Sérgio; Sousa, Alexandre; Fraga, Sérgio Loureiro; Martins, Alfredo; Sousa, J. Borges de; Pereira, Fernando LoboThis paper reports the design of a new remotely operated underwater vehicle (ROV), which has been developed at the Underwater Systems and Technology Laboratory (USTL) - University of Porto. This design is contextualized on the KOS project (Kits for underwater operations). The main issues addressed here concern directional drag minimization, symmetry, optimized thruster positioning, stability and layout of ROV components. This design is aimed at optimizing ROV performance for a set of different operational scenarios. This is achieved through modular configurations which are optimized for each different scenario.
- Field experiments for marine casualty detection with autonomous surface vehiclesPublication . Martins, Alfredo; Dias, André; Almeida, José Miguel; Ferreira, Hugo Miguel; Almeida, Carlos Valente; Silva, Guilherme Amaral; Machado, Diogo Cabral; Sousa, João Ricardo; Pereira, Pedro Oliveira; Matos, Aníbal; Lobo, Vitor; Silva, EduardoIn this paper we present a set of field tests for detection of human in the water with an unmanned surface vehicle using infrared and color cameras. These experiments aimed to contribute in the development of victim target tracking and obstacle avoidance for unmanned surface vehicles operating in marine search and rescue missions. This research is integrated in the work conducted in the European FP7 research project Icarus aiming to develop robotic tools for large scale rescue operations. The tests consisted in the use of the ROAZ unmanned surface vehicle equipped with a precision GPS system for localization and both visible spectrum and IR cameras to detect the target. In the experimental setup, the test human target was deployed in the water wearing a life vest and a diver suit (thus having lower temperature signature in the body except hands and head) and was equipped with a GPS logger. Multiple target approaches were performed in order to test the system with different sun incidence relative angles. The experimental setup, detection method and preliminary results from the field trials performed in the summer of 2013 in Sesimbra, Portugal and in La Spezia, Italy are also presented in this work.
- Radar Based Collision detection developments on USV ROAZ IIPublication . Almeida, Carlos; Franco, Tiago; Ferreira, Hugo; Martins, Alfredo; Santos, Ricardo; Almeida, José Miguel; Carvalho, João; Silva, EduardoThis work presents the integration of obstacle detection and analysis capabilities in a coherent and advanced C&C framework allowing mixed-mode control in unmanned surface systems. The collision avoidance work has been successfully integrated in an operational autonomous surface vehicle and demonstrated in real operational conditions. We present the collision avoidance system, the ROAZ autonomous surface vehicle and the results obtained at sea tests. Limitations of current COTS radar systems are also discussed and further research directions are proposed towards the development and integration of advanced collision avoidance systems taking in account the different requirements in unmanned surface vehicles.
- MarinEye – A tool for marine monitoringPublication . Martins, Alfredo; Dias, André; Silva, Eduardo; Ferreira, Hugo; Dias, Ireneu; Almeida, José Miguel; Torgo, Luís; Gonçalves, Marco; Guedes, Maurício; Dias, Nuno; Jorge, Pedro; Mucha, Ana Paula; Magalhães, Catarina; Carvalho, Maria de Fátima; Ribeiro, Hugo; Almeida, C. Marisa R.; Azevedo, Isabel; Ramos, Sandra; Borges, Teresa; Leandro, Sérgio Miguel; Maranhão, Paulo; Mouga, Teresa; Gamboa, Roberto; Lemos, Marco; Santos, Antonina dos; Silva, Alexandra; Teixeira, Bárbara Frazão e; Bartilotti, Cátia; Marques, Raquel; Cotrim, SóniaThis work presents an autonomous system for marine integrated physical-chemical and biological monitoring – the MarinEye system. It comprises a set of sensors providing diverse and relevant information for oceanic environment characterization and marine biology studies. It is constituted by a physical-chemical water properties sensor suite, a water filtration and sampling system for DNA collection, a plankton imaging system and biomass assessment acoustic system. The MarinEye system has onboard computational and logging capabilities allowing it either for autonomous operation or for integration in other marine observing systems (such as Observatories or robotic vehicles. It was designed in order to collect integrated multi-trophic monitoring data. The validation in operational environment on 3 marine observatories: RAIA, BerlengasWatch and Cascais on the coast of Portugal is also discussed.
- An automated maneuver control framework for a remotely operated vehiclePublication . Fraga, S. L.; Sousa, J. Borges de; Girard, Anouck; Martins, AlfredoAn automated maneuver control framework for a remotely operate vehicle (ROV) is presented. This framework entails a three-layered control architecture, a principled approach to design and implementation within the architecture, and hybrid systems design techniques. The control architecture is structured according to the principle of composition of vehicle motions from a minimal set of elemental maneuvers that are designed and verified independently. The principled approach is based on distributed hybrid systems techniques, and spans integrated design, simulation and implementation as the same model is used throughout. Hybrid systems control techniques are used to synthesize the elemental maneuvers and to design protocols, which coordinate the execution of elemental maneuvers within a complex maneuver. The architecture is fault-tolerant by design since it uses verified maneuvers. This work is part of the Inspection of Underwater Structures (IES) project whose main objective is the implementation of a ROV-based system for the inspection of underwater structures