Dissertations / Theses on the topic 'Unmanned water vehicles'

The majority of the Earths surface is covered with water, and the air-water interface (AWI) acts as the natural boundary between the atmosphere and the water. The AWI is an important ecological zone in natural aquatic habitats that governs transport of material and energy between bodies of water and the atmosphere. Little is known about temperature profiles and biological transport across the boundary layers at the air-water interface, and how wind interactions at the AWI affects them. New technologies such as sensors and unmanned surface vehicles (USV) need to be developed and used to address this knowledge gap. The goal of the research is to study population densities of the bacteria Pseudomonas syringae below, at and above the AWI using USV equipped with specialized sensors. The first specific objective was to map temperature profiles and resolve the boundary layer at the AWI using high resolution distributed temperature sensing (HR-DTS) on board an unmanned surface vehicle (USV). Our second research objective was to sample microbes from the water with a USV at multiple depths and locations. Our third research objective was to sample microbes from the atmosphere with a USV at the AWI. Our fourth research objective was to track and localize hazardous agents (tracer dyes) using a USV in aqueous environments.<br>Ph. D.

In civil and environmental engineering numerous are the applications that require prior collection of data on the ground. When it comes to hydraulic modelling, valuable topographic and morphology features of the region are one of the most useful of them, yet often unavailable, expensive or difficult to obtain. In the last few years UAVs entered the scene of remote sensing tools used to deliver such information and their applications connected to various photo-analysis techniques have been tested in specific engineering fields, with promising results. The content of this thesis aims contribute to the growing literature on the topic, assessing the potentialities of UAV and SfM photogrammetry analysis in developing terrain elevation models to be used as input data for numerical flood modelling. This thesis covered all phases of the engineering process, from the survey to the implementation of a 1D hydraulic model based on the photogrammetry derived topography The area chosen for the study was the Limpopo river. The challenging environment of the Mozambican inland showed the great advantages of this technology, which allowed a precise and fast survey easily overcoming risks and difficulties. The test on the field was also useful to expose the current limits of the drone tool in its high susceptibility to weather conditions, wind and temperatures and the restricted battery capacity which did not allow flight longer than 20 minutes. The subsequent photogrammetry analysis showed a high degree of dependency on a number of ground control points and the need of laborious post-processing manipulations in order to obtain a reliable DEM and avoid the insurgence of dooming effects. It revealed, this way, the importance of understanding the drone and the photogrammetry software as a single instrument to deliver a quality DEM and consequently the importance of planning a survey photogrammetry-oriented by the adoption of specific precautions. Nevertheless, the DEM we produced presented a degree of spatial resolution comparable to the one high precision topography sources. Finally, considering four different topography sources (SRTM DEM 30 m, lidar DEM 1 m, drone DEM 0.6 m, total station&amp;RTK bathymetric cross sections o.5 m) the relationship between spatial accuracy and water depth estimation was tested through 1D, steady flow models on HECRAS. The performances of each model were expressed in terms of mean absolute error (MAE) in water depth estimations of the considered model compared to the one based on the bathymetric cross-sections. The result confirmed the potentialities of the drone for hydraulic engineering applications, with MAE differences between lidar, bathymetry and drone included within 1 m. The calibration of SRTM, Lidar and Drone based models to the bathymetry one demonstrated the relationship between geometry detail and roughness of the cross-sections, with a global improvement in the MAE, but more pronounced for the coarse geometry of SRTM.

This work aims to contribute on the design of a Bimodal Unmanned Underwater and Air System (BUUAS). This research project will first present background informations of current hybrid UAV concepts with a focus on the different types of propulsion mechanisms used in air/water transition. Then a brief description of BUUAS will lead to requirements for the transition mechanism that this work aims to develop. After a section dedicated to the description of a short-impulse thruster layout, theoretical and experimental approaches are used to determine the amount of thrust generated. As second design step, a simplified UAV version is used to test the transition phase using the designed thruster. Finally, a section is dedicated to a design layout description with the thruster and an optimized propeller. Future work is proposed to continue in the development of this project, with a short description of folding wing and propulsion system integration concepts.

Closed loop control of an unmanned underwater vehicle (UUV) in the dynamically difficult environment of shallow water requires explicit consideration of the highly coupled nature of the governing non-linear equations of motion. This coupling between an UUV's six degrees of freedom (6 DOF) is particularly important when attempting complex maneuvers such as coordinated turns (e.g. simultaneous dive and heading change) or vehicle hovering in such an environment. Given the parameter and modelling uncertainties endemic to these equations of motion, then a robust 6 DOF sliding controller employing six-element vector sliding surfaces provides a framework in which satisfactory UUV control can be achieved in shallow water. The vehicle equations of motion are developed and cast in a form that is amenable to non-linear sliding control design. A complete 6 DOF sliding controller with vector sliding surfaces is then formulated via a Lyapunov-like analysis. The sliding controller is then modified via a weighted least-squares approach to work with a particular UUV which has only 4 DOF control authority available. The modified controller is shown to work well for a variety of commanded UUV maneuvers in the presence of significant environmental disturbances and vehicle hydrodynamic parameter uncertainties via numerical simulation. Use of the signals generated by the controller are shown to be of utility in vehicle buoyancy control.

This report is about the implementation of autonomy and control on a water quality measuring unmanned surface vehicle. The project was termed Catfish and involved five teams focusing on different aspects of the initial goal to create an autonomous three-part system; a surface drone, a submerged drone and flying drone. In this iteration of the Catfish project the focus laid on creating the surface drone and submerged drone as the Catfish project will improve over generations of thesis projects. The author of the report was in the Control and Autonomy team and had been tasked with giving the surface drone the autonomy needed to make this project viable. Existing advances made in autonomy was adopted and tested. With the help of estimation algorithms, and sensor fusion, a flight controller navigates the surface drone between a set of GPS waypoints. It is also able to counteract the external forces wind, waves and stream to keep its position. To reach this autonomy four test phases were conducted on a pre-prototype with progressively increased difficult autonomy starting with manual control and ending in advanced autonomy. When the advanced missions were executed the speed and accuracy of two different thruster configurations were examined and the best performing out of the two was implemented on the final prototype the other teams had designed. The project ended with a fully autonomous system that was able to execute all the navigational maneuvers required to operate autonomous water quality measuring missions.<br>Den här rapporten handlar om implementationen av autonomi och kontroll på en vattenkvalitetsmätande vattenburen drönare. Projektet fick namnet Catfish och blev indelat i fem teams som fokuserade på olika aspekter av ett 3-delsystem; en vattenburen, en undervattens och en flygande drönare. I denna iteration av Catfish projektet fokuserade medlemmarna på att utveckla den vattenburna och undervattens drönaren då projektet kommer fortsätta utvecklas under kommande generationer av Catfish projektrapporter. Författaren av den här rapporten ingick i ett team som hette "Control and Autonomy" och hade i uppgift att installera en autonom intelligens till den vattenburna drönaren för att göra Catfish prototypen användbar. Befintliga framsteg inom forskningsområdet blev granskade och testade. Genom att använda uppskattningsalgoritmer och "sensor fusion" lyckades en "flight controller" navigera drönaren mellan GPS waypoints och även behålla sin position genom att motverka krafterna från vind, vågor och strömmar. För att uppnå denna nivå av autonomi utför en förprototyp fyra test faser av ökad autonomisk svårhetsgrad. Under uppdraget blev hastigheten och precisionen av två olika motoruppsättningar undersöka och den som presterade bäst blev implementerad på den slutgiltig designen som de andra teamen hade utvecklat. Projektet avslutades med att ett fullt autonomt system blev utvecklat som var kapabel till att utföra alla navigationsmanövrar nödvändiga för att genomföra autonoma vattenkvalitetsmätningsuppdrag.

The unmanned vehicles (UV) and its applications are growing exponentially. Using the radio control is the most common way to control these types of vehicles for being a simple and cheap method to control an UV. However, it doesn’t have a visual interface that allows the user to see the vehicle’s information such as battery status, speed, distance, geolocation, etc. To deal with this problem, some mobile and desktop applications have been developed. To communicate between the control device and the vehicle, dongles are commonly used to establish the connection using radio, Bluetooth or Wi-Fi. In most cases, these technologies don’t allow the user to control at long distances, Beyond Line Of-Sight (BLOS), and these applications are focused to use mostly on multi-copters, and most of the times, they only allow to connect a vehicle at a time. The purpose of this dissertation is to study the reliability of an application able to control multiple types of vehicles, such as aerial, land and water vehicles. This application allows the user to connect multiple vehicles at the same time using a single device, easily change the vehicle assigned to control, by using mobile networks to perform the communication between the developed application and the vehicle. In this way, it will be possible to connect a 3D – hybrid vehicle, which is a vehicle capable of moving in water, land and air environments, allowing the user to control the vehicle at long distances with video feedback. To achieve the purpose of this dissertation, it was developed an Android application to allow controlling the vehicle by using mobile networks to communicate. In the vehicle, besides the common electronics used in an unmanned vehicle (ESC’s, motors, batteries, controller board, etc.), it will be used a Raspberry Pi 2 model B with a 3rd Generation (3G) and 4th Generation (4G) dongle that will connect the vehicle to the internet, routing the messages coming from the controller board placed in the vehicle to the mobile application. It was also developed a server application to do the user management and exchange the messages coming from both platforms: vehicle and application.<br>Os veículos não tripulados e as suas aplicações estão em forte crescimento. O uso de rádio controlo é a maneira mais comum de controlar estes tipos de veículos, sendo o método mais barato e simples de controlar um veículo não tripulado. Contudo, não têm uma interface visual que permita ao utilizador ver as informações do veículo, tais como o nível da bateria, a velocidade, distância, geolocalização, entre outros. Para ajudar com este problema, têm sido desenvolvidas algumas aplicações para dispositivos móveis e computadores, que permitem controlar e monitorizar este tipo de veículos. Para estabelecer a comunicação entre o dispositivo de controlo e o veículo, são frequentemente usados dongles para comunicar por rádio, Bluetooth ou Wi-Fi. Na maioria dos casos, estas tecnologias não possibilitam ao utilizador o controlo a longas distâncias, para além da linha de vista, e costumam ser focadas para o uso em multicopteros, possibilitando, na maioria dos casos, a ligação de um único veículo. O âmbito desta dissertação pretende estudar e desenvolver uma aplicação com elevada fiabilidade, capaz de controlar vários tipos de veículos, nomeadamente, veículos aéreos, terrestres e aquáticos. Esta aplicação irá permitir a ligação a vários veículos ao mesmo tempo, trocar facilmente o veiculo a controlar, recorrendo aos sistemas de comunicação móveis celulares, 3ª geração (3G ) e 4ª geração (4G) para garantir a comunicação entre a aplicação desenvolvida e o veículo não tripulado. Seguindo estes princípios, é possível controlar um veículo 3D hibrido (em modo de ar, terra e mar). Esta permite ao utilizador controlar o veículo a longas distâncias com o uso de uma transmissão de vídeo. Para alcançar o objetivo desta dissertação foi desenvolvida uma aplicação Android para possibilitar o controlo recorrendo às redes móveis celulares. No veículo, além da eletrónica habitual, para um veículo não tripulado (motores, ESC’s, baterias, etc.), será também utilizado um Raspberry Pi 2 modelo B com um dongle 3G/4G que liga o veículo, redirecionando as mensagens vindas da placa de controlo para a aplicação móvel. Para a comunicação entre a aplicação e o veículo foi também desenvolvida uma aplicação instalada no servidor que é responsável pela gestão de utilizadores e pela troca de mensagens vindas de ambas as plataformas: veículo e aplicação.

碩士<br>建國科技大學<br>自動化工程系暨機電光系統研究所<br>105<br>The design concept of this study is to design a low-cost and high-efficiency water and underwater detection of unmanned vehicle design. This study uses the design phase method to carry out unmanned vehicle design, discuss the required demand and function analysis to complete the product concept design, And then the initial concept of the design of advanced research detail design, complete the required paper production information. In order to meet the concept of low cost and high efficiency materials selection and procurement. And then in accordance with the experimental process planning table, the water and underwater detection of unmanned vehicle production. I made the water no one carrier, small size, light weight, simple production, good stability, can be effectively controlled in the static waters, is conducive to static waters and shallow water on the operation. The vehicle is equipped with two WIFI photography system, which can carry out both water and underwater investigation. The images taken on the surface can be connected with the mobile phone, which is beneficial to the operator to watch and manipulate and avoid the interference of water obstructions. The structure and feasibility of water navigation through Unmanned SurfaceVehicle (USV) have been completed and studied in this paper. Keywords: water unmanned vehicle, tracking photography, underwater camera, underwater photography

碩士<br>中原大學<br>機械工程研究所<br>106<br>The quality of water in reservoir is an issue to water consumption nowadays. The traditional way of water quality is tested by sampling at specific location by staffs. Asides from investigating the geographic environment and hydrology before sampling, arranging human resource and transportation are also needed. With such dangerous, time-and-cost-consuming works, therefore CYME and CYEE dedicate to marine drone development. In order to improve the problems above, authors expect to develop a manual marine drone to let staffs have access to sampling at some unreachable locations. This Thesis mainly challenge the alteration and control of the boat. First, we do the evaluation of stability of the boat and assess if the boat would overturn with interference of wind and waves. Then we made statical stability curve. On mechanic construction aspect, we upgraded the power system, making it has more power to load the equipment in order to proceed sampling. And last, we tested the boat in reservoir and ensure the water sampling could be done.

碩士<br>國立高雄科技大學<br>電訊工程系<br>107<br>The impact of rivers on human life is extremely great. Nearly 70% of agricultural water is taken from river water and groundwater. If household and industrial wastewater are discharged into rivers without authorization, it will affect the development of ecology and industry around the river. In order to avoid pollution to rivers, sampling and analysis of water quality in Taiwan's rivers is required. The existing water sampling methods are mainly manpower. If the sampling site is like an environment that muddy terrain, unsafe water flow and so on, it is quite difficult to find suitable sampling locations from the main pollution sources. This paper uses the unmanned vehicle mobility combined with the pumping water system to develop an unmanned vehicle automatic water sampling system to avoid sampling inconvenient problems. In addition, the water sampling equipment carried o the unmanned vehicle itself is equipped with an imaging device and a pH detection module, through which the river environment management and monitoring. The image and the pH sensing value are transmitted through the wireless data transmission module. Realize immediate monitoring of river environment changes and detect whether rivers are contaminated. At present, for the monitoring range in the Houjin River, we can conduct river water sampling and coastal pollution source monitoring at multiple monitoring points by a single flight. It is hoped that the construction of the automatic water sampling system of the unmanned vehicle will improve the traditional water sampling method, so that the sampling personnel do not have to waddle in person to avoid the danger of the sampling personnel.

碩士<br>中原大學<br>機械工程研究所<br>106<br>Whether the water quality of the reservoir is safe or not is an issue for people&apos;&apos;s daily water-use. At present, the traditional reservoir water quality test is mainly for personnel to arrive at a specific location for fixed-point sampling. In addition to surveying the geography environment and the hydrological sites, staff and vehicles must also be arranged. The sampled data is insufficient compared to the overall water area, so the accuracy of the data is inadequate. The survey is accompanied by a certain degree of danger and costs a lot of time, money and manpower. Therefore, Zhongyuan Mechanical Engineering Department cooperated with Zhongyuan Environmental Engineering Department to develop an unmanned inspection vehicle to improve the problems we faced. Hoping it will replace manpower with intelligent machine in the future. In view of the current testing operations, this paper hopes to develop unmanned inspection vehicle to improve the traditional water-quality-testing method. Along with auto technology controlling the unmanned boat, the boat can sample at the detection points which is difficult to reach or unreachable, and simultaneously increase the data which are sampled in the area. With average value as a result, the deviation value can be reduced. The main challenge of this paper is to assemble and control the unmanned boat. In the controlling part, we need to control the motor in order to move the unmanned boat and calculate the equation of motion for the boat. In the mechanic part, the boat&apos;&apos;s power system is improved to drive the instrument. There are also a cooling system and a modular waterproof system. Our team participated in the “Vision Program” held by the 2017 National Applied Research Laboratories with this unmanned vehicle research and development technology. We head to Silicon Valley, USA, and show this technology on the international stage.

碩士<br>國立中興大學<br>水土保持學系所<br>103<br>River flow measurement technologies are divided into intrusive and nonintrusive methods. Intrusive method requires infield operations. Its protocols are time consuming, and likely to cause damages of operator and instrument. Nonintrusive methods require fewer operators and instrument damages can be avoided from directly attaching to the flow. Nonintrusive measurements use radar or image velocimetry to measure the velocities at the free surface.The image velocimetry, such as large scale particle image velocimetry (LSPIV), access not only the point velocity but the flow velocities in an area. Flow properties of an area hold the promise of providing spatially information of flow fields. This study attempts to construct a mobile system UAV-LSPIV by using an unmanned aerial vehicle (UAV) with LSPIV to measure flows in a field. The mobile system is based on a six-rotor UAV helicopter, with a Sony nex5T camera, a gimbal, and an image transfer device. UAV attaches an activate gimbal, which help maintain the camera lens orthogonal to the water surface and prevent images from being distorted. The image transfer device can monitor the captured image simultaneously. Verification of LSPIV was first set up in laboratory, the deviation from velocity measured by current meter and LSPIV is below 9%. After that, the mobile system was applied to field experiments under different flow conditions. In the low flow experiments, the deviation of velocities measured by UAV-LSPIV and handhold Acoustic Doppler Velocimeter (ADV) is under 8%. In the high flow experiment, the deviation of velocities measured by UAV-LSPIV and Particle Tracking Velocimetry (PTV) is about 4%. The results of the field experiments suggest that the UAV-LSPIV is applicable to measure the surface flows in the fields.

碩士<br>國立金門大學<br>理工學院工程科技碩士在職專班土木工程組<br>106<br>The remote sensing techniques have been widely applied to environmental issues, such as water quality monitoring. The water quality in Kinmen, Taiwan has been worsening for a long time because of the exuberant alga growth. According to the observed Carlson index, the trophic classes of the reservoirs mostly are eutrophic or hypereutrophic. The bad water quality also hampers the water purification. In order to increase the amount of potable water, a project of water receiving from China is processing and will be finished in a few years. The four small reservoirs, including Tian-Pu, Jin-sha, Rung-Hu, and Shi-Hu reservoirs, are selected as the study sites, which cover a mere several hundred-thousand m2. A multispectral sensor carried on an unmanned aerial vehicles (UAV) coupled with sampling in situ is employed to estimate the water quality parameters, including chlorophyll-a (Chl-a), secchi disk depth (SDD), and turbidity. In this research, an enumeration-based algorithm, called matching pixel by pixel (MPP), is presented to establish robust empirical model between band ratio and water quality parameter. The experimental results indicate that, while MPP can reduce the influence of specular reflection on regression model establishment, specular reflection does hamper the correction of thematic map production. Due to water fluidity, sampling in situ should be followed by UAV imaging as soon as possible. Excluding turbidity, the obtained estimation accuracy can satisfy the national standard.

This study investigates the reliability and accuracy of elasmobranch abundance data collected using baited remote underwater video (BRUV) surveys and unmanned aerial vehicle (UAV) surveys, and shark interaction with equipment in the Cocos (Keeling) Islands, a remote territory of Australia. The primary aim of the study was to provide insight into strengths and drawbacks of both BRUV and UAV techniques in the study of large pelagic elasmobranchs in shallow tropical ecosystems and to clarify elasmobranch interaction with underwater apparatus. Aerial and underwater surveys were conducted simultaneously, with the underwater component rotating between use of bait, BRUV and no stimuli between each survey, while a Phantom 4 DJI drone hovered directly above study site. The difference between BRUV and bait-only surveys was not significant overall. The drone, the BRUV and the bait recorded similar enough data that our analysis could not detect a noticeable difference and both were deemed capable tools in shallow water shark research.<br>Este estudo investiga a precisão e rigor da abundância da amostra de elasmobrânquios analisada através de pesquisa utilizando câmeras submarinas controladas remotamente (BRUV), bem como um dispositivo voador não tripulado (UAV), e captar a interação das espécies com o equipamento aquático. O objetivo do estudo foi produzir conjuntos de informação idêntica de forma a comparar e determinar a variação de cálculos entre ambas as metodologias usadas. O principal objectivo foi entender os pontos fortes e fracos de ambas as técnicas usadas, BRUV e UAV, no estudo de grandes elasmobrânquios pelágicos em ecossistemas tropicais de pouca profundidade, assim como, clarificar a interação entre os elasmobrânquios e o dispositivo submarino. O BRUV (que literalmente se traduz em ‘Sistema de câmaras de vídeo submarino iscadas’) é um método muito usado para estudar o ambiente subaquático, uma vez que gera grandes benefícios em relação às pesquisas operadas por mergulhadores. A razão por detrás disso é que a tecnologia pode capturar espécies tímidas ou enigmáticas que podem evitar o tipo de levantamento anterior e, portanto, não são vistas e estão sub-representadas nos estudos marinhos. Tem sido um método confiável durante um longo período de tempo. O drone, objecto voador não tripulado, é uma introdução mais recente, pioneira em silvicultura e agricultura, na qual câmeras aéreas não tripuladas podem voar sobre paisagens para obter o ponto de vista de um pássaro e recolher dados dessa maneira. Embora, em terra, os drones sejam considerados disruptivos, as espécies submersas comprovadamente não são afetadas pela introdução de um drone no seu ambiente, o que dá margem ao potencial de estudos imparciais. No entanto, antes que possam começar, é crucial fazer uma comparação entre este novo método e um método antigo e confiável para realmente confirmar que os drones têm potencial não apenas como um método imparcial, mas também preciso para captar a abundância subaquática e até mesmo traços comportamentais. Este estudo revelou várias informações importantes relativas às capacidades de ambas as tecnologias usadas aqui; ou seja, os métodos BRUV e UAV. Essencialmente, o projeto confirmou que ambos realizam um nível altamente satisfatório quando usados em várias configurações, produzindo simultaneamente resultados estatisticos semelhantes. Isso é positivo por várias razões, confirma que o uso de BRUV em estudos anteriores é justificado, mas também abre a porta para que a tecnologia de drones se torne um componente significativo de estudos futuros. Este estudo pode até revelar o benefício de usar ambos os métodos lado a lado de uma maneira altamente complementar pois ambos capturam os mesmos valores de abundância quando usados no mesmo contexto, capturando diferentes aspectos e características dos ambientes bióticos e abióticos que cercam as espécies de estudo. Por exemplo, os drones são usados para detectar tubarões de forma a proteger surfistas em áreas costeiras, portanto, este estudo é positivo para o público e para a comunidade científica. Usar drones em estudos, é uma nova maneira de perceber o ambiente marinho. Enquanto os mamíferos, que respiram à superfície, provaram repetidas vezes que são perfeitamente adequados aos estudos aéreos, este estudo aborda os parâmetros de pesquisa de animais com uma estrutura comportamental diferente: os elasmobrânquios pelágicos que habitam em águas de pouca profundidade. O objetivo era perceber como os elasmobrânquios poderiam ser beneficiados pela introdução da ciência aérea, se for o caso. O estudo foi realizado nas Ilhas Cocos (Keeling), que são um território remoto da Austrália, a Noroeste de Perth, onde os tubarões nunca foram caçados e, portanto, existem em grande abundância. A água fornece condições perfeitas para as comparações a serem estudadas, uma vez que é consistentemente superficial e clara com uma variedade de substratos para fornecer uma gama de habitats para comparações. No CKI, foram realizados estudos aéreos e subaquáticos, nos quais a isca foi colocada na água para observar a atracção de tubarões no campo de visão de cada câmera: a câmera aérea, voando a 20m com um campo de visão extremamente amplo; ou a câmera subaquática, com alta precisão e resolução, mas um campo de visão relativamente menor. Os métodos e materiais são descritos na tese em inglês. Para resumir, o drone deveria ser voado três vezes em cada trajecto, para ser referido como "antes, durante e depois". Antes do voo do segundo sector, um BRUV, ou uma bolsa de isca de rede, seria colocado na água directamente abaixo do local onde o drone pairaria. Desta forma, duas configurações idênticas estavam a ser gravadas simultaneamente para apresentar conjuntos de dados directamente comparáveis. A razão para implantar BRUV e isca em ocasiões separadas foi para investigar a resposta dos sujeitos do estudo (os elasmobrânquios) à introdução de engodo, de sardinha (Sardinops sagax), presa conhecida que eles provavelmente reconhecerão e responderão rapidamente, comparada à BRUV, um grande dispositivo de aço com duas câmeras incluídas. O objetivo aqui foi entender se os elasmobrânquios exibem comportamento de evitação em direção ao equipamento subaquático que poderia causar desvios nos estudos de BRUV. Naturalmente, ambas as técnicas de estudo envolveram uma série de pontos fortes e fracos que vão desde o custo-benefício, duração da bateria até a capacidade real de capturar espécies-alvo em cima de indivíduos não-alvo. O objetivo da análise era entender o significado desses resultados para, então, perceber se um dos métodos era superior ou, na verdade, complementar e começar a entender as limitações do levantamento aéreo. Nós consideramos os resultados muito semelhantes, com várias observações separadas e diferenças no somatório de abundância ao longo do tempo, o que sugere que os dois podem ser emparelhados para melhorar o poder estatístico de estudos futuros. Embora as descobertas do estudo preparem o caminho para o desenvolvimento de outras questões e o exame de cada método, os parâmetros do estudo foram bastante amplos. Embora esse tenha sido o objetivo da tese, agora ele deve ser desenvolvido usando comparações mais específicas e, o mais importante, um conjunto maior de dados para melhorar o poder estatístico e reduzir o efeito de anomalias nos resultados gerais. Como esperávamos, aprendemos que ambos os métodos apresentam uma maneira cientificamente sólida de medir a abundância de nossos elasmobrânquios alvo, ao mesmo tempo em que obtemos insights sobre as melhores metodologias para realizar futuros estudos aéreos de forma a obter os resultados mais consistentes.

Dissertação de mestrado em Ciências e Tecnologias do Ambiente (área de especialização em Monitorização e Remediação Ambiental)<br>Este trabalho apresenta a caraterização de um rio urbano, o Torto/Panóias, que atravessa áreas densamente povoadas na cidade de Braga. Esta caracterização conduziu a uma avaliação do potencial de risco de ocorrência de cheias e da qualidade da água, sedimentos e solos, dependente dos níveis de contaminação observados. A caracterização morfológica foi realizada utilizando um veículo aéreo não tripulado (VANT), que permitiu a obtenção do modelo tridimensional do terreno. O estudo foi baseado em diferentes cenários de cota de inundação, determinando as possíveis áreas inundáveis. A área máxima de inundação ocorre à cota 54 m, sugerindo um cenário de grande preocupação, uma vez que todas as infraestruturas (estradas, habitações, fábricas) e campos agrícolas serão inundados devido ao aumento do nível da água do rio. Em relação à qualidade ambiental, o estudo foi dedicado principalmente à água do rio. No entanto, os sedimentos e o solo agrícola das suas margens foram também submetidos a análise. A água foi colhida em sete locais de amostragem, em três campanhas de campo, e analisadas quanto a indicadores físico-químicos (pH, condutividade elétrica, oxigénio dissolvido e temperatura, sólidos suspensos totais - SST), hidroquímicos (aniões e metais principais e traço), químicos e bioquímicos (Carência química e bioquímica de oxigénio – CQO e CBO5) e ainda microbiológicos (coliformes totais). Os sedimentos e solos foram estudados relativamente à presença de elementos potencialmente tóxicos (metais e arsénio). Os indicadores utilizados mostraram tendências espaciais e sazonais relacionadas com as descargas de efluentes orgânicos e com processos de diluição, capazes de atenuar a poluição. A aplicação de um índice de qualidade da água mostrou a degradação ao longo do curso do rio, passando de boa para aceitável e má. A recuperação verificou-se apenas após a confluência no rio Cávado, onde é novamente classificada como boa. Os sedimentos e solos foram comparados com os valores de referência das normas de Ontário (recomendados pela Agência Portuguesa do Ambiente), indicando contaminação metálica dos sedimentos. Os solos revelaram incumprimento relativamente ao mercúrio, elemento preocupante pela sua toxicidade. Os indicadores de qualidade sugerem a ocorrência de poluição difusa e localizada com origem agrícola e orgânica, esta possivelmente proveniente de descargas clandestinas e da principal estação de tratamento de águas residuais da cidade (ETAR de Frossos).<br>This work presents a characterization of an urban river, the Torto/Panóias, which runs through densely populated areas in the city of Braga. This characterization led to an assessment of the risk of floods and of the environmental quality depending on the levels of water, sediments and soil contamination. The morphological characterization was carried out using an unmanned aerial vehicle (VANT), which allowed the three-dimensional model of the terrain to be obtained. The study was based on different scenarios of flood quota, determining the potential floodable areas in each case. The maximum area of flood occurs at a level of 54 m, suggesting a scenario of great concern as all infrastructures, roads, buildings, factories and agricultural fields will be covered with water due to the rising level of the River. Regarding environmental quality, the study was mainly dedicated to the evaluation of the quality of the river water. Moreover, the sediments transported by the river and the agricultural soil of the cultivated margins were also subject to analyses. Water samples were then taken at seven sampling points in three field campaigns and analyzed for physicalchemical (pH, electric conductivity, dissolved oxygen and temperature, total suspended solids – TSS), hydrochemical (anions and major and trace metals), chemical and biochemical oxygen demand – COD; BOD5) as well as microbiological (coliforms) indicators. Sediments and soils were taken in three sites and analyzed for potential toxic elements (metals and arsenic.) The used indicators showed spatial and seasonal trends related with the main discharges of organic effluents, namely from Frossos wastewater treatment plant, and with the dilution able to attenuate pollution, respectively. The application of a quality index indicates the conversion of the water from good to acceptable and bad along the course of the river. Recovery of the quality occurs only after confluence in the Cávado River, where it is classified again as good. Sediments and soils were compared with the reference values of Ontario standards (approved by the Portuguese environmental agency), indicating metallic contamination for sediments. Soils revealed incompliance relatively to the concerning toxic element mercury. The indicators suggested the occurrence of diffuse and localized pollution related with agricultural and with organic effluents, possibly from clandestine discharges and from the main waste water treatment plant (WWTP) of the Braga city (Frossos WWTP).

Atualmente, a Inteligência Artificial (IA) e o sub-campo Machine Learning (ML) estão em constante desenvolvimento e procura por parte de diferentes áreas científicas. Neste caso, ocorreu uma fusão entre a IA e a agricultura, especificamente na vertente da viticultura. Esta dissertação apresenta um sistema composto por um drone com uma câmara térmica acoplada, que foi usada para sobrevoar vinhas, para obter fotografias (imagens) térmicas. Estas imagens contêm leituras de temperatura da vinha e do solo em cada pixel, de modo a analisar as regiões que contêm valores baixos de temperatura, que representam zonas com alta concentração de humidade. O objetivo deste trabalho é implementar um algoritmo de Machine Learning para detetar e localizar áreas de humidade nas imagens térmicas. Este sistema tem duas características principais: a alta resolução da câmara térmica, pois permite saber exatamente a temperatura em qualquer local da imagem; A utilização de um algoritmo de Machine Learning para classificar as regiões automaticamente com excesso de níveis de humidade. Após a realização de vários testes, o algoritmo obteve resultados na ordem dos 82% de precisão, o que demonstrou uma performance satisfatória para o alcance do objetivo proposto. Esta classificação é muito útil na agricultura de precisão, a fim de otimizar os recursos hídricos usados na rega da cultura agrícola, poupando assim água, energia e colaborando com uma atitude em prol da sustentabilidade e na tomada de decisão dos agricultores.<br>The Artificial Intelligence (AI) and the Machine Learning (ML) subfield are currently in constant development and demand from different scientific areas. In this case, a merger between AI and agriculture took place, specifically in the field of viticulture. This dissertation presents a system composed by a drone with an attached thermal camera, which was used to fly over vineyards taking thermal images. These images contain vine and soil temperature readings on each pixel, in order to analyse the regions containing low temperature values, which show areas with a high concentration of humidity. The objective of this work is to implement a Machine Learning algorithm to detect and locate areas of humidity in thermal images. This system has two main features: the high resolution of the thermal camera, as it allows to know exactly the temperature anywhere in the image area; and the use of a Machine Learning algorithm to automatically classify regions with an excess of humidity levels. After several tests, the algorithm obtained results of around 82% accuracy, which showed a satisfactory performance in achieving the proposed objective. This classification is very useful in precision agriculture, in order to optimise the water resources used in crops irrigation, thus saving water and energy and it contributes to an attitude towards sustainability and supports farmers’ decision making.

With the increasing demand of water and underwater exploration, more and more electric unmanned surface vehicles (USV) are put into use in recent years. However, because of the present battery technology limits, these devices require to be recharged frequently that is a challenging problem taking into account the complex water environment where these equipments are acting. To improve safety and convenience of USV charging a wireless power transfer (WPT) system is proposed in this dissertation. In this case, the boat can be controlled to go to the charging facilities. During charging by the implemented WPT system, the state of charging can be remotely monitored by host computer. The moving control is based on embedded system. The relative position between transmitting coil and receiving coil is supposed to be sensed by magnetic sensor, since the relative position has great impact on transmission efficiency. The remote monitoring software was implemented in the host computer and was developed in LABVIEW. A graphical user interface was developed to control the boat moving and collect the data from the WPT and the boat sensors. The effectiveness of the proposed system was tested for instance in the laboratory environment and in-field tests are also planned in the near future.<br>Com a crescente procura da exploração em ambientes aquáticos e subaquáticos , os veículos elétricos de superfície não tripulados ("electric unmanned surface vehicle" -USV) têm sido cada vez mais utilizados nestes últimos anos. No entanto, devido aos limites atuais relacionados com a tecnologia utilizada nas baterias, os dispositivos precisam de ser recarregados com frequência para poderem operar num ambiente aquático complexo. Para melhorar a segurança e a conveniência do carregamento da bateria de um USV, um sistema para recarregamento da bateria de um barco não tripulado através de transferência de energia sem fios("wireless power transfer" - WPT) é proposto nesta dissertação. Neste caso de estudo, o barco tem a capacidade de ser controlado para chegar a um ponto de recarregamento da bateria, que se encontra fixado por uma doca mecânica. Enquanto o sistema WPT érecarregado, os dados associados ao processo de recarregamento da bateria podem ser monitorizados por um computador host. O controlo da movimentação do barco é baseado num sistema embebido. A posição relativa entre a bobina transmissora e a bobina receptora deve ser detectada pelo sensor magnético, uma vez que a posição relativa tem um grande impacto na eficiência da transmissão. Em termos do computador host, foi utilizado o software LABVIEW para programar a interface que permite controlar o movimento do barco e recolher os dados. Finalmente, a eficácia do sistema proposto foi experimentada e testada num ambiente de laboratório.