600 research outputs found
ICARUS Training and Support System
The ICARUS unmanned tools act as gatherers, which acquire enormous amount of information. The management of all these data requires the careful consideration of an intelligent support system. This chapter discusses the High-Performance Computing (HPC) support tools, which were developed for rapid 3D data extraction, combination, fusion, segmentation, classification and rendering. These support tools were seamlessly connected to a training framework. Indeed, training is a key in the world of search and rescue. Search and rescue workers will never use tools on the field for which they have not been extensively trained beforehand. For this reason, a comprehensive serious gaming training framework was developed, supporting all ICARUS unmanned vehicles in realistic 3D-simulated (based on inputs from the support system) and real environments
Command and Control Systems for Search and Rescue Robots
The novel application of unmanned systems in the domain of humanitarian Search and Rescue (SAR) operations has created a need to develop specific multi-Robot Command and Control (RC2) systems. This societal application of robotics requires human-robot interfaces for controlling a large fleet of heterogeneous robots deployed in multiple domains of operation (ground, aerial and marine). This chapter provides an overview of the Command, Control and Intelligence (C2I) system developed within the scope of Integrated Components for Assisted Rescue and Unmanned Search operations (ICARUS). The life cycle of the system begins with a description of use cases and the deployment scenarios in collaboration with SAR teams as end-users. This is followed by an illustration of the system design and architecture, core technologies used in implementing the C2I, iterative integration phases with field deployments for evaluating and improving the system. The main subcomponents consist of a central Mission Planning and Coordination System (MPCS), field Robot Command and Control (RC2) subsystems with a portable force-feedback exoskeleton interface for robot arm tele-manipulation and field mobile devices. The distribution of these C2I subsystems with their communication links for unmanned SAR operations is described in detail. Field demonstrations of the C2I system with SAR personnel assisted by unmanned systems provide an outlook for implementing such systems into mainstream SAR operations in the future
Using operational scenarios in a virtual reality enhanced design process
Maritime user interfaces for ships’ bridges are highly dependent on the context in which they are used, and rich maritime context is difficult to recreate in the early stages of user-centered design processes. Operations in Arctic waters where crews are faced with extreme environmental conditions, technology limitations and a lack of accurate navigational information further increase this challenge. There is a lack of research supporting the user-centered design of workplaces for hazardous Arctic operations. To meet this challenge, this paper reports on the process of developing virtual reality-reconstructed operational scenarios to connect stakeholders, end-users, designers, and human factors specialists in a joint process. This paper explores how virtual reality-reconstructed operational scenarios can be used as a tool both for concept development and user testing. Three operational scenarios were developed, implemented in a full mission bridge simulator, recreated in virtual reality (VR), and finally tested on navigators (end-users). Qualitative data were captured throughout the design process and user-testing, resulting in a thematic analysis that identified common themes reflecting the experiences gained throughout this process. In conclusion, we argue that operational scenarios, rendered in immersive media such as VR, may be an important and reusable asset when supporting maritime design processes and in maritime training and education
Realistic simulation and animation of clouds using SkewT-LogP diagrams
Nuvens e clima são tópicos importantes em computação gráfica, nomeadamente na simulação e animação de fenómenos naturais. Tal deve-se ao facto de a simulação de fenómenos naturais−onde as nuvens estão incluídas−encontrar aplicações em filmes, jogos e simuladores de voo. Contudo, as técnicas existentes em computação gráfica apenas permitem representações de nuvens simplificadas, tornadas possíveis através de dinâmicas fictícias que imitam a realidade. O problema que este trabalho pretende abordar prende-se com a simulação de nuvens adequadas para utilização em ambientes virtuais, isto é, nuvens com dinâmica baseada em física que variam ao longo do tempo.
Em meteorologia é comum usar técnicas de simulação de nuvens baseadas em leis da física, contudoossistemasatmosféricosdeprediçãonuméricasãocomputacionalmente pesados e normalmente possuem maior precisão numérica do que o necessário em computação gráfica. Neste campo, torna-se necessário direcionar e ajustar as características físicas ou contornar a realidade de modo a atingir os objetivos artísticos, sendo um fator fundamental que faz com que a computação gráfica se distinga das ciências físicas. Contudo, simulações puramente baseadas em física geram soluções de acordo com regras predefinidas e tornam-se notoriamente difíceis de controlar.
De modo a enfrentar esses desafios desenvolvemos um novo método de simulação de nuvens baseado em física que possui a característica de ser computacionalmente leve e simula as propriedades dinâmicas relacionadas com a formação de nuvens. Este novo modelo evita resolver as equações físicas, ao apresentar uma solução explícita para essas equações através de diagramas termodinâmicos SkewT/LogP. O sistema incorpora dados reais de forma a simular os parâmetros necessários para a formação de nuvens. É especialmente adequado para a simulação de nuvens cumulus que se formam devido ao um processo convectivo. Esta abordagem permite não só reduzir os custos computacionais de métodos baseados em física, mas também fornece a possibilidade de controlar a forma e dinâmica de nuvens através do controlo dos níveis atmosféricos existentes no diagrama SkewT/LogP.
Nestatese,abordámostambémumoutrodesafio,queestárelacionadocomasimulação de nuvens orográficas. Do nosso conhecimento, esta é a primeira tentativa de simular a formação deste tipo de nuvens. A novidade deste método reside no fato de este tipo de nuvens serem não convectivas, oque se traduz nocálculodeoutrosníveis atmosféricos. Além disso, atendendo a que este tipo de nuvens se forma sobre montanhas, é também apresentadoumalgoritmoparadeterminarainfluênciadamontanhasobreomovimento da nuvem.
Em resumo, esta dissertação apresenta um conjunto de algoritmos para a modelação e simulação de nuvens cumulus e orográficas, recorrendo a diagramas termodinâmicos SkewT/LogP pela primeira vez no campo da computação gráfica.Clouds and weather are important topics in computer graphics, in particular in the simulation and animation of natural phenomena. This is so because simulation of natural phenomena−where clouds are included−find applications in movies, games and flight simulators. However, existing techniques in computer graphics only offer the simplified cloud representations, possibly with fake dynamics that mimic the reality. The problem that this work addresses is how to find realistic simulation of cloud formation and evolution, that are suitable for virtual environments, i.e., clouds with physically-based dynamics over time.
It happens that techniques for cloud simulation are available within the area of meteorology, but numerical weather prediction systems based on physics laws are computationally expensive and provide more numerical accuracy than the required accuracy in computer graphics. In computer graphics, we often need to direct and adjust physical features, or even to bend the reality, to meet artistic goals, which is a key factor that makes computer graphics distinct from physical sciences. However, pure physically-based simulations evolve their solutions according to pre-set physics rules that are notoriously difficult to control.
In order to face these challenges we have developed a new lightweight physically-based cloudsimulationschemethatsimulatesthedynamicpropertiesofcloudformation. This new model avoids solving the physically-based equations typically used to simulate the formation of clouds by explicitly solving these equations using SkewT/LogP thermodynamic diagrams. The system incorporates a weather model that uses real data to simulate parameters related to cloud formation. This is specially suitable to the simulation of cumulus clouds, which result from a convective process. This approach not only reduces the computational costs of previous physically-based methods, but also provides a technique to control the shape and dynamics of clouds by handling the cloud levels in SkewT/LogP diagrams.
In this thesis, we have also tackled a new challenge, which is related to the simulation oforographic clouds. From ourknowledge, this isthefirstattempttosimulatethis type of cloud formation. The novelty in this method relates to the fact that these clouds are non-convective, so that different atmospheric levels have to be determined. Moreover, since orographic clouds form over mountains, we have also to determine the mountain influence in the cloud motion.
In summary, this thesis presents a set of algorithms for the modelling and simulation of cumulus and orographic clouds, taking advantage of the SkewT/LogP diagrams for the first time in the field of computer graphics
Autonomous Vehicles
This edited volume, Autonomous Vehicles, is a collection of reviewed and relevant research chapters, offering a comprehensive overview of recent developments in the field of vehicle autonomy. The book comprises nine chapters authored by various researchers and edited by an expert active in the field of study. All chapters are complete in itself but united under a common research study topic. This publication aims to provide a thorough overview of the latest research efforts by international authors, open new possible research paths for further novel developments, and to inspire the younger generations into pursuing relevant academic studies and professional careers within the autonomous vehicle field
Visibility in underwater robotics: Benchmarking and single image dehazing
Dealing with underwater visibility is one of the most important challenges in autonomous underwater robotics. The light transmission in the water medium degrades images making the interpretation of the scene difficult and consequently compromising the whole intervention. This thesis contributes by analysing the impact of the underwater image degradation in commonly used vision algorithms through benchmarking. An online framework for underwater research that makes possible to analyse results under different conditions is presented. Finally, motivated by the results of experimentation with the developed framework, a deep learning solution is proposed capable of dehazing a degraded image in real time restoring the original colors of the image.Una de las dificultades más grandes de la robótica autónoma submarina es lidiar con la falta de visibilidad en imágenes submarinas. La transmisión de la luz en el agua degrada las imágenes dificultando el reconocimiento de objetos y en consecuencia la intervención. Ésta tesis se centra en el análisis del impacto de la degradación de las imágenes submarinas en algoritmos de visión a través de benchmarking, desarrollando un entorno de trabajo en la nube que permite analizar los resultados bajo diferentes condiciones. Teniendo en cuenta los resultados obtenidos con este entorno, se proponen métodos basados en técnicas de aprendizaje profundo para mitigar el impacto de la degradación de las imágenes en tiempo real introduciendo un paso previo que permita recuperar los colores originales
Control-law for Oil Spill Mitigation with a team of Heterogeneous Autonomous Vehicles
Oil spill incidents in the sea or harbours occur with some regularity during exploration, production, and transport of petroleum products. In order to mitigate the impact of the oil spill in the marine life, immediate, safety, effective and eco-friendly actions must be taken. Autonomous vehicles can assume an important contribution by establishing a cooperative and coordinated intervention.
This dissertation presents the development of two path planning control-laws, the first one an autonomous surface vehicle (ASV) being able to contour the oil spill while s deploying microorganisms and nutrients (bioremediation) capable of mitigate and contain the oil spill spread, and the second one for a unmanned aerial vehicle (UAV) in order to perform the coverage of the entire spillage area with the same microorganisms and nutrients deployment capabilities.
In order to validate both methods, a simulation environment was developed in Gazebo with a oil spill scenario, an ASV and an UAV. Field tests have been conducted in the Leixões Harbour in Porto, Portugal.Incidentes relacionados com derrames de petróleo no oceano ou em portos ocorrem com alguma regularidade, durante a exploração, produção e transporte de petróleo e seus derivados. Para mitigar o impacto desses derramamentos na fauna e flora marinha de uma forma imediata, segura, efectiva e amiga do ambiente novas ações são necessárias.
Veículos autónomos podem providenciar uma importante contribuição estabelecendo uma intervenção cooperativa e coordenada.
Esta dissertação apresenta o desenvolvimento de dois algoritmos de controlo para o planeamento de trajectórias, a primeira para um veículo de superfície autónomo (ASV) ser capaz de contornar o perímetro do derrame enquanto distribui microorganismos e nutrientes (bio-remediação), capazes de mitigar e conter a propagação do derramamento de petróleo e a segunda para um veículo aéreo não-tripulado (UAV) ser capaz de cobrir todo a área de derrame enquanto distribui os mesmos microorganismos e nutrientes.
De forma a validar ambos os métodos, um ambiente de simulação foi desenvolvido em Gazebo com cenário do derrame de petróleo, um ASV e um UAV. Testes de campo foram realizados no porto de Leixões, no Porto, Portugal
Research Naval Postgraduate School, v.12, no.3, October 2002
NPS Research is published by the Research and Sponsored Programs, Office of the Vice President and Dean of Research, in accordance with NAVSOP-35. Views and opinions expressed are not necessarily those of the Department of the Navy.Approved for public release; distribution is unlimited
Autonomous High-Precision Landing on a Unmanned Surface Vehicle
THE MAIN GOAL OF THIS THESIS IS THE DEVELOPMENT OF AN AUTONOMOUS
HIGH-PRECISION LANDING SYSTEM OF AN UAV IN AN AUTONOMOUS BOATIn this dissertation, a collaborative method for Multi Rotor Vertical Takeoff and Landing
(MR-VTOL) Unmanned Aerial Vehicle (UAV)s’ autonomous landing is presented. The
majority of common UAV autonomous landing systems adopt an approach in which the
UAV scans the landing zone for a predetermined pattern, establishes relative positions,
and uses those positions to execute the landing. These techniques have some shortcomings,
such as extensive processing being carried out by the UAV itself and requires a lot
of computational power. The fact that most of these techniques only work while the UAV
is already flying at a low altitude, since the pattern’s elements must be plainly visible to
the UAV’s camera, creates an additional issue. An RGB camera that is positioned in the
landing zone and pointed up at the sky is the foundation of the methodology described
throughout this dissertation. Convolutional Neural Networks and Inverse Kinematics
approaches can be used to isolate and analyse the distinctive motion patterns the UAV
presents because the sky is a very static and homogeneous environment. Following realtime
visual analysis, a terrestrial or maritime robotic system can transmit orders to the
UAV.
The ultimate result is a model-free technique, or one that is not based on established
patterns, that can help the UAV perform its landing manoeuvre. The method is trustworthy
enough to be used independently or in conjunction with more established techniques
to create a system that is more robust. The object detection neural network approach was
able to detect the UAV in 91,57% of the assessed frames with a tracking error under 8%,
according to experimental simulation findings derived from a dataset comprising three
different films. Also created was a high-level position relative control system that makes
use of the idea of an approach zone to the helipad. Every potential three-dimensional
point within the zone corresponds to a UAV velocity command with a certain orientation
and magnitude. The control system worked flawlessly to conduct the UAV’s landing
within 6 cm of the target during testing in a simulated setting.Nesta dissertação, é apresentado um método de colaboração para a aterragem autónoma
de Unmanned Aerial Vehicle (UAV)Multi Rotor Vertical Takeoff and Landing (MR-VTOL).
A maioria dos sistemas de aterragem autónoma de UAV comuns adopta uma abordagem
em que o UAV varre a zona de aterragem em busca de um padrão pré-determinado, estabelece
posições relativas, e utiliza essas posições para executar a aterragem. Estas técnicas
têm algumas deficiências, tais como o processamento extensivo a ser efectuado pelo próprio
UAV e requer muita potência computacional. O facto de a maioria destas técnicas só
funcionar enquanto o UAV já está a voar a baixa altitude, uma vez que os elementos do
padrão devem ser claramente visíveis para a câmara do UAV, cria um problema adicional.
Uma câmara RGB posicionada na zona de aterragem e apontada para o céu é a base da
metodologia descrita ao longo desta dissertação. As Redes Neurais Convolucionais e as
abordagens da Cinemática Inversa podem ser utilizadas para isolar e analisar os padrões
de movimento distintos que o UAV apresenta, porque o céu é um ambiente muito estático
e homogéneo. Após análise visual em tempo real, um sistema robótico terrestre ou
marítimo pode transmitir ordens para o UAV.
O resultado final é uma técnica sem modelo, ou que não se baseia em padrões estabelecidos,
que pode ajudar o UAV a realizar a sua manobra de aterragem. O método é
suficientemente fiável para ser utilizado independentemente ou em conjunto com técnicas
mais estabelecidas para criar um sistema que seja mais robusto. A abordagem da rede
neural de detecção de objectos foi capaz de detectar o UAV em 91,57% dos fotogramas
avaliados com um erro de rastreio inferior a 8%, de acordo com resultados de simulação
experimental derivados de um conjunto de dados composto por três filmes diferentes.
Também foi criado um sistema de controlo relativo de posição de alto nível que faz uso
da ideia de uma zona de aproximação ao heliporto. Cada ponto tridimensional potencial
dentro da zona corresponde a um comando de velocidade do UAV com uma certa orientação
e magnitude. O sistema de controlo funcionou sem falhas para conduzir a aterragem
do UAV dentro de 6 cm do alvo durante os testes num cenário simulado.
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