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Dans le cadre de la collecte sous-marine d'échantillons biologiques et minéraux pour la recherche scientifique par un robot sous-marin équipé de bras manipulateurs, ce projet de thèse a pour but principal le développement de nouvelles techniques de manipulation des échantillons, plus fiables, permettant d'en assurer l'intégrité physique et leur exploitabilité par les chercheurs. Les nouvelles techniques de manipulation proposées prennent en compte l'actionnement particulier des nouveaux bras électriques sous-marins équipant les engins récents, afin d'augmenter la précision du positionnement des outils embarqués par le manipulateur. Un outil amovible, compliant, et mesurant les efforts d'interaction entre les bras du sous-marin et leur environnement est aussi proposé, et des méthodes permettant de tirer partie des caractéristiques de cet outil sont développées et testées expérimentalement. L'engin sous-marin hybride HROV Ariane, équipé de deux bras électriques hétérogènes, offre la plateforme opérationnelle pour la validation expérimentale des solutions proposées. / The research carried out in the scope of this doctorate degree aims to develop innovative techniques to improve the collection of biological and mineral samples underwater using robotic manipulators. The end goal is to enhance the handling by robotic means in order to maximise sample quality provided to marine scientists. The proposed techniques are based on an in-depth analysis of the robotic arm actuators used in most recent underwater intervention vehicles, in order to improve the accuracy of the positionning of the tools held by the manipulator arms. An instrumented tool has also been developed with the aim to measure the reaction forces and adapt the interaction between the arm's end-effector and its environment to improve samples handling. These methods and the other contributions described in this thesis have been experimentally validated using Ifremer's hybrid-ROV Ariane equipped with two electrically actuated heterogeneous robotic arms.

L'utilisation des véhicules sous-marins (ROV, AUV, gliders) s'est considérablement accrue ces dernières décennies, aussi bien dans le domaine de l'offshore ou de l'océanographie, que pour des applications militaires. Dans cette thèse, nous abordons le problème particulier de la commande des véhicules sous-marins à faible inertie et fort rapport puissance/inertie. Ces derniers constituent des systèmes fortement non linéaires, dont la dynamique est susceptible de varier au cours du temps (charge embarquée, caractéristiques des propulseurs, variation de salinité...) et qui sont très sensibles aux perturbations environnementales (chocs, traction sur l'ombilical...). Afin d'assurer des performances de suivi de trajectoire satisfaisantes, il est nécessaire d'avoir recours à une commande adaptative qui compense les incertitudes ou les variations des paramètres du modèle dynamique, mais également qui rejette les perturbations, telles que les chocs. A cette fin, nous proposons dans ce manuscrit, l'étude théorique et la validation expérimentale de plusieurs lois de commande pour véhicules sous-marins. Nous analysons tout d'abord des approches classiques dans ce domaine (commande PID et commande par retour d'état non linéaire), puis nous les comparons avec deux autres architectures de commande. La première est la commande adaptative L1 non linéaire, introduite en 2010 notamment pour la commande des véhicules aériens, et implémentée pour la première fois sur un véhicule sous-marin. Le découplage entre adaptation et robustesse permet l'utilisation de très grands gains d'adaptation (et donc une convergence plus rapide des paramètres estimés, sans aucune connaissance a priori), sans pour autant dégrader la stabilité. La seconde méthode, que nous proposons et qui constitue l'apport principal de cette thèse, est une évolution de la commande L1, permettant d'en améliorer les performances lors du suivi d'une trajectoire variable. Nous présentons une analyse de stabilité de cette commande, ainsi que sa comparaison expérimentale avec les autres lois de commande (commande PID, commande adaptative par retour d'état non linéaire et commande adaptative L1 standard). Ces expérimentations ont été réalisées sur un mini-ROV et plusieurs scenarii ont été étudiés, permettant ainsi d'évaluer, pour chaque loi, sa robustesse et son aptitude à rejeter les perturbations. / Underwater vehicles have gained an increased interest in the last decades given the multiple tasks they can accomplish in various fields, ranging from scientific to industrial and military applications. In this thesis, we are particularly interested in the category of vehicles having a high power to weight ratio. Different challenges in autonomous control of such highly unstable systems arise from the inherent nonlinearities and the time varyingbehavior of their dynamics. These challenges can be increased by the low inertia of this class of vehicles combined with their powerful actuation. A self tuning controller is therefore required in order to avoid any performance degradation during a specific mission. The closed-loop system is expected to compensate for different kinds of disturbances or changes in the model parameters. To solve this problem, we propose in this work the design,analysis and experimental validation of different control schemes on an underwater vehicle. Classical methods are initially proposed, namely the PID controller and the nonlinear adaptive state feedback (NASF) one, followed by two more advanced schemes based on the recently developed L1 adaptive controller. This last method stands out among the other developed ones in its particular architecture where robustness and adaptation are decoupled. In this thesis, the original L1 adaptive controller has been designed and successfullyvalidated then an extended version of it is proposed in order to deal with the observed time lags occurring in presence of a varying reference trajectory. The stability of this latter controller is then analysed and real-time experimental results for different operating conditions are presented and discussed for each proposed controller, assessing their performance and robustness.

Les applications sous-marines actuelles exigent la réalisation de travaux de différentes natures dans des zones de plus en plus vastes et toujours plus profondes. La conception et l'utilisation de flottilles d'AUV dans ce contexte est un véritable challenge. Les bénéfices attendus sontmultiples. Premièrement, cela doit permettre de minimiser les coûts grâce à une répartition de ceux-ci sur l'ensemble de la flottille : la perte d'un AUV ou son mauvais fonctionnement ne remettront pas en cause l'intégralité de la mission. Deuxièmement, l'utilisation d'une flottilledoit de fait permettre de réduire le temps d'exécution d'une mission grâce à la parallélisation de certaines tâches. Enfin, la réalisation d'une mission par une flottille permet de conserver le caractère spécialisé des AUV et donc d'envisager plus facilement leur réutilisation dansd'autres contextes. Cependant, les approches de coopération multi-AUV existantes sont limitées par deux principaux verrous : (1) le nombre de communications induit et (2) la gestion de l'hétérogénéité potentielle d'une flottille.L'approche que nous proposons vise à répondre à ces problématiques.L'idée principale est de combiner une approche de coopération réactive avec une approche organisationnelle. L'approche de coopération réactive permet l'échange des signaux de communication très simples. Cependant, elle ne permet de résoudre que des problèmes de coopération de nature assez restreinte qui concernent essentiellement la coordination spatiale de véhicules homogènes. La première contribution de cette thèse est l'extension de l'approche satisfaction-altruisme. Un nouveau mécanisme décisionnel réactif, capable de considérer des actions coopératives de diverses natures, est proposé. La deuxième contribution consiste à spécifier les contextes d'interactions réactives à l'aide d'une approche organisationnelle. Le modèle organisationnel Agent/Groupe/Rôle est utilisé pour avoir une représentation explicite de l'organisation de la flottille. Les concepts de groupe, mais surtout de rôle, sont employés dans l'adressage des signaux de communication et permettent la mise en oeuvre d'interactions hétérogènes avec une grande modularité. L'ensemble est intégré dans une nouvelle architecture logicielle, appelée REMORAS, destinée à équiper des véhicules sous-marins autonomes. Une validation de la faisabilité de notre approche est proposée à l'aide d'une simulation de plusieurs scénarios mettant en jeu des AUV hétérogènes. / Underwater marine applications are nowadays branching into various fields covering larger and deeper zones. Performing the required tasks with the aid of AUV flotillas is a real challenge. However, the advantages of using such a new technology are numerous. Firstly, this would highly reduce the cost of the mission thanks to the distribution of this former among the various AUV: the loss of one AUV or its bad functioning will not degrade the performance of the flotilla in general. Secondly, the use of a flotilla reduces the execution time of a mission given the parallelization of certain tasks. Finally, any mission can be accomplished by the flotilla by taking into consideration the specificity of each AUV. In fact, each of these vehicles holds different characteristics rendering the global architecture heterogeneous and therefore applicable in different contexts. However, the methods concerned with multi-AUV cooperation are hindered by two main limitations: (1) the number of communications induced and (2) the management of the heterogeneity in the flotilla.The proposed approach aims at responding to these challenges. The principal idea is to combine this reactive cooperational approach with an organizational one. The reactive cooperational approach allows the exchange of simple communication signals. However, it does not help in solving the problems of cooperation that are very constrained and that mainly concern the spatial coordination of homogeneous vehicles. The first contribution in this thesis is the extension of the satisfaction-altruism approach. A new reactive decisional mechanism capable of considering the cooperative actions of various natures is proposed. The second contribution consists in specifying the context of reactive interactions based on an organizational approach. The organizational model Agent/Group/Role is used in order to have an explicit representation of the flotilla. The concepts of "group" and especially "role" are used in the attribution of the communication signals allowing the accomplishment of heterogeneous interactions with a big modularity. A new concept is therefore born and is integrated in a new software architecture called REMORA intended to equip autonomous underwater vehicles. This proposed new method has been validated through various numerical simulations in different scenarios putting at stake heterogeneous AUV.

<div>Sediment has a significant impact on social, economic, and environmental systems. With the need for an effective sediment management and monitoring system growing more important,</div><div>a method for precisely and reproducibly obtaining sediment samples that represent the actual environment is essential for water resource management and researchers across aquatic domains (such as lakes, rivers, reservoirs, mine drainage ponds, and wastewater lagoons).</div><div>Sediment sampling is usually carried out less frequently than water sampling because of the cost and labor involved. However, more frequent sediment sampling and an increase in the</div><div>range of the sampling area are necessary to more effectively monitor the ecosystem and water quality.</div><div>To fill this gap, robotic approaches for sediment sampling have been introduced. However, they are not tailored to a sediment sampling method and do not focus on the quality of</div><div>the sediment sample. Moreover, there are many challenges involved in developing such a sediment sampling system for the surface water of rivers, streams, lakes, ponds reservoirs, and lagoons. Thus, this study can be conducted to investigate to design and develop an uncrewed sediment sampling system for surface-water environments based on marine robot platforms that are capable of collecting intact sediment samples from a range of sediment types. As part of this study, an unmanned surface vehicle (USV) was used to deploy the underwater sediment sampler (USS) at the sampling locations. The USS adopted a core sampling method to collect the sediment samples. The specific requirements were integrated, taking into consideration the challenges posed by surface water and underwater environments, to design and develop an unmanned sediment sampling system.</div><div>The USV has two missions - deploying and positioning. Users can deploy the USV with the USS to the desired sampling area. Once the USV arrives, it has to maintain its position while launching the USS and during the sampling process. The USS also has two missions — launching and sampling. The USS must be a negative-buoyancy platform so it can reach the bottom and maintain its stability during sampling. To sample the sediment, the USS has to generate a sampling pattern. We defined and formulated challenges based on the missions of each platform.</div><div><div>The USV consists of three sub-systems; propulsion, launching, and monitoring system to accomplish missions. The propulsion system and launching system are necessary to accomplish deploying and positioning missions. The propulsion system is consists of two thrusters to navigate the USV. The launching system is to launch anchors for positioning and the USS for sampling. The monitoring system is to monitor and control other systems on-board via online video. The USS can generate sampling patterns based on three motions; linear, rotational, and hammering motion. We integrated servos, sensors, and mechanical components to generate three motions. The main system of the USS is completely waterproof, even for linear and rotational motion with enclosures, O-rings, and rubber bellows. Since the USS operates underwater, the water pressure causes the pressure difference between inside and outside the enclosure. We designed a pressure-equalizing system to compensate for the volume change because of sampling motions and pressure differences. Extensive field experiments were conducted to evaluate the proposed system. Users can monitor and control the system from the base station based on all data and images from each platform. The evaluation of the system is based on the data from sensors installed on each platform. Deploying and positioning missions of the USV can be shown based on the trajectory data. Launching and sampling missions of the USS can be validated based on depth, orientation, and reaction force data.</div><div>Contributions of the proposed unmanned sediment sampling system are, 1) It is the first unmanned system with a novel design to collect the less disturbed sediment samples even</div><div>from the inaccessible area and remove the potential risks of human-based sampling tasks, 2) We proposed and integrated a new sediment sampling pattern based on the sediment</div><div>sampling pattern analysis to increase the quality of sediment samples by minimizing disturbances, and 3) The proposed unmanned sediment sampling system is the first step toward the autonomous environmental monitoring system for more effective environmental monitoring.</div><div>This proposed system has many potential elements that can be a total solution for robotic environmental monitoring in addition to other features such as water sampling system, and various types of sensing system.</div></div>

This thesis presents the integration of an acoustic tracking system within an autonomous underwater AUV (AUV) to enable real-time tracking of sharks tagged with artificial acoustic sources. The tracking system consists of two hydrophones and a receiver unit that outputs a measurement of the relative angle to the tagged shark. Since only two hydrophones are used, the sign of the relative angle measurement is unknown. To overcome this ambiguity, a particle filter algorithm was developed to estimate the position of the acoustic source. When combined with an active control system that drives vehicle to obtain different orientations with respect to the acoustic source, real-time autonomous localization, tracking, and following of a tagged shark is shown to be possible. Four types of ocean experiments were used to validate the system including: 1) AUV tracking of a stationary tag, 2) AUV tracking of a tagged kayak, 3) AUV tracking of a tagged AUV, and 4) AUV tracking of a tagged shark. These experiments were analyzed with respect to the localization error, associated error variance, and distance between the AUV and the tag. The final shark tracking experiments took place in SeaPlane Lagoon, Los Angeles, CA, where the AUV was able to autonomously track and follow a tagged Leopard Shark for several hours.

Monitoring the health status of coral reefs is a crucial activity in protecting the environment. One way is by conducting "Manta tow surveys." For a long time, these surveys were conducted by a diver holding a board being towed by a boat. In this thesis, we propose a new vehicle design that works as a platform to help conduct the "towboard" activities for underwater coral reef surveys. It utilizes paravane or depressor features which is a common tool used by fishermen to catch fish at a specified depth. The vehicle offers a compact size, modular design, and control surfaces to maneuver around and close to reef walls. The thesis describes the architecture of the overall system and its components, the design decisions, the mechanical interfaces, and a brief description of the dynamics. An experiment is conducted to validate the design and verify system performance, measuring pressure, speed, and orientation. The prototype is presented as a proof of concept.

Les robots sous-marins peuvent aujourd'hui évoluer dans des environnements complexes difficilement accessibles à l'Homme pour des raisons de coût ou de sécurité. Ils peuvent donc intervenir dans une grande variété de missions en environnement aquatique. Or, la complexité de ces milieux impose de doter le vecteur robotique d'une autonomie opérationnelle suffisante afin qu'il puisse mener sa mission à bien tout en préservant son intégrité. Cela nécessite de développer des lois de commande répondant aux spécificités de l'application. Ces lois de commande se basent sur des connaissances provenant de différentes disciplines scientifiques ce qui souligne l'interdisciplinarité inhérente à la robotique. Une fois la loi de commande développée, il faut implémenter le contrôleur sur le robot sous forme de logiciel de contrôle basé sur une architecture logicielle temps-réel.Or la conception actuelle des lois de commande, sous forme de blocs "monolithiques", rend difficile l'évolution d'une loi de commande d'une application à l'autre, l'intégration de connaissances provenant d'autres disciplines scientifiques que ne maitrisent pas forcément les automaticiens et pénalisent son implémentation sur des architectures logicielles qui nécessitent la modularité. Pour résoudre ces problèmes nous cherchons à proprement séparer les différentes connaissances afin que chacune soit aisément manipulable, son rôle clair et que les relations établies entre les différentes connaissances soient explicites. Cela permettra en outre une projection plus efficace sur l'architecture logicielle. Nous proposons donc un nouveau formalisme de description des lois de commande selon une composition modulaire d'entités de base appelées Atomes et qui encapsulent les différents éléments de connaissance. Nous nous intéressons également à l'établissement d'une meilleure synergie entre les aspects automatique et génie logiciel qui se construit autour de préoccupations communes telles que les contraintes temporelles et la stabilité. Pour cela, nous enrichissons nos Atomes de contraintes chargées de véhiculer les informations relatives à ces aspects temporels. Nous proposons également une méthodologie basée sur notre formalisme afin de guider l'implémentation de nos stratégies de commande sur un Middleware temps-réel, dans notre cas le Middleware ContrACT développé au LIRMM.Nous illustrons notre approche par diverses fonctionnalités devant être mises en oeuvre lors de missions d'exploration de l'environnement aquatique et notamment pour l'évitement de parois lors de l'exploration d'un aquifère karstique. / Underwater robots can nowadays operate in complex environments in a broad scope of missions where the use of human divers is difficult for cost or safety reasons. However the complexity of aquatic environments requires to give the robotic vector an autonomy sufficient to perform its mission while preserving its integrity. This requires to design control laws according to application requirements. They are built on knowledge from several scientific fields, underlining the interdisciplinarity inherent to robotics. Once the control law designed, it must be implemented as a control Software working on a real-time Software architecture.Nonetheless the current conception of control laws, as "monolithic" blocks, makes difficult the adaptation of a control from an application to another and the integration of knowledge from various scientific fields which are often not fully understood by control engineers. It also penalizes the implementation of control on Software architectures, at least its modularity and evolution. To solve those problems we seek a proper separation of knowledge so that each knowledge item can be easily used, its role precisely defined and we want to reify the interactions between them. Moreover this will allow us a more efficient projection on the Software architecture. We thus propose a new formalism for control laws description as a modular composition of basic entities named Atoms used to encapsulate the knowledge items.We also aim at building a better synergy between control and software engineering based on shared concerns such as temporal constraints and stability. Hence we extend the definition of our Atoms with constraints carrying information related to their temporal behaviour. We propose as well a methodology relying on our formalism to guide the implementation of control on a real-time Middleware. We will focus on the ContrACT Middleware developed at LIRMM.Finally we illustrate our approach on several robotic functionalities that can be used during aquatic environments exploration and especially for wall avoidance during the exploration of a karst aquifer.

This research investigates the impact a Remotely Operated Vehicle (ROV) program has on student interest in, and perception of, technology and engineering (sTEm). ROV programs embed areas of science, technology, engineering and math (STEM) into their curriculum; however, emphasis for this study is placed on interest and perception of the "T" and "E" of STEM. Although there are many articles detailing the benefits of ROV programs, there is little empirical data documenting the impact on student interest and perception of sTEm. This study outlines the background of a few major ROV programs in the U.S.; specifically Utah Underwater Robotics (UUR), an ROV statewide program within a landlocked state, the methods for gathering data and findings from a sTEm survey instrument administered to over 300 students ranging from 6th to 12th grade who participated in a five-month ROV program and near 50 students who did not. Key findings include: 1. Males were more interested in technology and engineering than females, regardless of whether they participated in the UUR ROV program. 2. Male and female students in the UUR program were more interested and had a more positive perception of engineering than those who did not participate in the UUR ROV program. 3. Females in the UUR program reported more interest in engineering careers and activities than females not in the program. 4. Females in the program reported more interest and self-efficacy in science than females not in the program. 5. Males in the UUR program reported more awareness of the positive and negative consequences of technology and engineering than those who did not participate.

Darrerament, l'interès pel desenvolupament d'aplicacions amb robots submarins autònoms (AUV) ha crescut de forma considerable. Els AUVs són atractius gràcies al seu tamany i el fet que no necessiten un operador humà per pilotar-los. Tot i això, és impossible comparar, en termes d'eficiència i flexibilitat, l'habilitat d'un pilot humà amb les escasses capacitats operatives que ofereixen els AUVs actuals. L'utilització de AUVs per cobrir grans àrees implica resoldre problemes complexos, especialment si es desitja que el nostre robot reaccioni en temps real a canvis sobtats en les condicions de treball. Per aquestes raons, el desenvolupament de sistemes de control autònom amb l'objectiu de millorar aquestes capacitats ha esdevingut una prioritat. Aquesta tesi tracta sobre el problema de la presa de decisions utilizant AUVs. El treball presentat es centra en l'estudi, disseny i aplicació de comportaments per a AUVs utilitzant tècniques d'aprenentatge per reforç (RL). La contribució principal d'aquesta tesi consisteix en l'aplicació de diverses tècniques de RL per tal de millorar l'autonomia dels robots submarins, amb l'objectiu final de demostrar la viabilitat d'aquests algoritmes per aprendre tasques submarines autònomes en temps real. En RL, el robot intenta maximitzar un reforç escalar obtingut com a conseqüència de la seva interacció amb l'entorn. L'objectiu és trobar una política òptima que relaciona tots els estats possibles amb les accions a executar per a cada estat que maximitzen la suma de reforços totals. Així, aquesta tesi investiga principalment dues tipologies d'algoritmes basats en RL: mètodes basats en funcions de valor (VF) i mètodes basats en el gradient (PG). Els resultats experimentals finals mostren el robot submarí Ictineu en una tasca autònoma real de seguiment de cables submarins. Per portar-la a terme, s'ha dissenyat un algoritme anomenat mètode d'Actor i Crític (AC), fruit de la fusió de mètodes VF amb tècniques de PG. / A considerable interest has arisen around Autonomous Underwater Vehicle (AUV) applications. AUVs are very useful because of their size and their independence from human operators. However, comparison with humans in terms of efficiency and flexibility is often unequal. The development of autonomous control systems able to deal with such issues becomes a priority. The use of AUVs for covering large unknown dynamic underwater areas is a very complex problem, mainly when the AUV is required to react in real time to unpredictable changes in the environment. This thesis is concerned with the field of AUVs and the problem of action-decision. The methodology chosen to solve this problem is Reinforcement Learning (RL). The work presented here focuses on the study and development of RL-based behaviors and their application to AUVs in real robotic tasks. The principal contribution of this thesis is the application of different RL techniques for autonomy improvement of an AUV, with the final purpose of demonstrating the feasibility of learning algorithms to help AUVs perform autonomous tasks. In RL, the robot tries to maximize a scalar evaluation obtained as a result of its interaction with the environment with the aim of finding an optimal policy to map the state of the environment to an action which in turn will maximize the accumulated future rewards. Thus, this dissertation is based on the principals of RL theory, surveying the two main classes of RL algorithms: Value Function (VF)-based methods and Policy Gradient (PG)-based techniques. A particular class of algorithms, Actor-Critic methods, born of the combination of PG algorithms with VF methods, is used for the final experimental results of this thesis: a real underwater task in which the underwater robot Ictineu AUV learns to perform an autonomous cable tracking task.