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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Optimization techniques for an ergonomic human-robot interaction / Techniques d’optimisation pour une interaction humain-robot ergonomique

Busch, Baptiste 27 February 2018 (has links)
L’interaction Humain-Robot est un domaine de recherche en pleine expansion parmi la communauté robotique. De par sa nature il réunit des chercheurs venant de domaines variés, tels que psychologie, sociologie et, bien entendu, robotique. Ensemble, ils définissent et dessinent les robots avec lesquels nous interagirons dans notre quotidien.Comme humains et robots commencent à travailler en environnement partagés, la diversité des tâches qu’ils peuvent accomplir augmente drastiquement. Cela créé de nombreux défis et questions qu’il nous faut adresser, en terme de sécurité et d’acceptation des systèmes robotiques.L’être humain a des besoins et attentes bien spécifiques qui ne peuvent être occultés lors de la conception des interactions robotiques. D’une certaine manière, il existe un besoin fort pour l’émergence d’une véritable interaction humain-robot ergonomique.Au cours de cette thèse, nous avons mis en place des méthodes pour inclure des critères ergonomiques et humains dans les algorithmes de prise de décisions, afin d’automatiser le processus de génération d’une interaction ergonomique. Les solutions que nous proposons se basent sur l’utilisation de fonctions de coût encapsulant les besoins humains et permettent d’optimiser les mouvements du robot et le choix des actions. Nous avons ensuite appliqué cette méthode à deux problèmes courants d’interaction humain-robot.Dans un premier temps, nous avons proposé une technique pour améliorer la lisibilité des mouvements du robot afin d’arriver à une meilleure compréhension des ses intentions. Notre approche ne requiert pas de modéliser le concept de lisibilité de mouvements mais pénalise les trajectoires qui amènent à une interprétation erronée ou tardive des intentions du robot durant l’accomplissement d’une tâche partagée. Au cours de plusieurs études utilisateurs nous avons observé un gain substantiel en terme de temps de prédiction et une réduction des erreurs d’interprétation.Puis, nous nous sommes attelés au problème du choix des actions et des mouvements qui vont maximiser l’ergonomie physique du partenaire humain. En utilisant une mesure d’ergonomie des postures humaines, nous simulons les actions et mouvements du robot et de l’humain pour accomplir une tâche donnée, tout en évitant les situations où l’humain serait dans une posture de travail à risque. Les études utilisateurs menées montrent que notre méthode conduit à des postures de travail plus sûr et à une interaction perçue comme étant meilleure. / Human-Robot Interaction (HRI) is a growing field in the robotic community. By its very nature it brings together researchers from various domains including psychology, sociology and obviously robotics who are shaping and designing the robots people will interact with ona daily basis. As human and robots starts working in a shared environment, the diversity of tasks theycan accomplish together is rapidly increasing. This creates challenges and raises concerns tobe addressed in terms of safety and acceptance of the robotic systems. Human beings havespecific needs and expectations that have to be taken into account when designing robotic interactions. In a sense, there is a strong need for a truly ergonomic human-robot interaction.In this thesis, we propose methods to include ergonomics and human factors in the motions and decisions planning algorithms, to automatize this process of generating an ergonomicinteraction. The solutions we propose make use of cost functions that encapsulate the humanneeds and enable the optimization of the robot’s motions and choices of actions. We haveapplied our method to two common problems of human-robot interaction.First, we propose a method to increase the legibility of the robot motions to achieve abetter understanding of its intentions. Our approach does not require modeling the conceptof legible motions but penalizes the trajectories that leads to late or mispredictions of therobot’s intentions during a live execution of a shared task. In several user studies we achievesubstantial gains in terms of prediction time and reduced interpretation errors.Second, we tackle the problem of choosing actions and planning motions that maximize thephysical ergonomics on the human side. Using a well-accepted ergonomic evaluation functionof human postures, we simulate the actions and motions of both the human and the robot,to accomplish a specific task, while avoiding situations where the human could be at risk interms of working posture. The conducted user studies show that our method leads to saferworking postures and a better perceived interaction.
222

Symbolic and Geometric Planning for teams of Robots and Humans / Planification symbolique et géométrique pour des équipes de robots et d'Humains

Lallement, Raphael 08 September 2016 (has links)
La planification HTN (Hierarchical Task Network, ou Réseau Hiérarchique de Tâches) est une approche très souvent utilisée pour produire des séquences de tâches servant à contrôler des systèmes intelligents. Cette thèse présente le planificateur HATP (Hierarchical Agent-base Task Planner, ou Planificateur Hiérarchique centré Agent) qui étend la planification HTN classique en enrichissant la représentation des domaines et leur sémantique afin d'être plus adaptées à la robotique, tout en offrant aussi une prise en compte des humains. Quand on souhaite générer un plan pour des robots tout en prenant en compte les humains, il apparaît que les problèmes sont complexes et fortement interdépendants. Afin de faire face à cette complexité, nous avons intégré à HATP un planificateur géométrique apte à déduire l'effet réel des actions sur l'environnement et ainsi permettre de considérer la visibilité et l'accessibilité des éléments. Cette thèse se concentre sur l'intégration de ces deux planificateurs de nature différente et étudie comment par leur combinaison ils permettent de résoudre de nouvelles classes de problèmes de planification pour la robotique. / Hierarchical Task Network (HTN) planning is a popular approach to build task plans to control intelligent systems. This thesis presents the HATP (Hierarchical Agent-based Task Planner) planning framework which extends the traditional HTN planning domain representation and semantics by making them more suitable for roboticists, and by offering human-awareness capabilities. When computing human-aware robot plans, it appears that the problems are very complex and highly intricate. To deal with this complexity we have integrated a geometric planner to reason about the actual impact of actions on the environment and allow to take into account the affordances (reachability, visibility). This thesis presents in detail this integration between two heterogeneous planning layers and explores how they can be combined to solve new classes of robotic planning problems
223

Simulace pohybu neholonomních mechanismů / Simulation of nonholonomic mechanisms’ motion

Byrtus, Roman January 2019 (has links)
Tato práce se zabývá simulacemi neholonomních mechanismů, konkrétně robotických hadů. V práci jsou uvedeny základní poznatky geometrické teorie řízení. Tyto poznatky jsou využity k odvození řídících modelů robotických systémů a následně jsou tyto modely simulovány v prostředí V-REP.
224

Expert Systems and Advanced Algorithms in Mobile Robots Path Planning / Expert Systems and Advanced Algorithms in Mobile Robots Path Planning

Abbadi, Ahmad January 2016 (has links)
Metody plánování pohybu jsou významnou součástí robotiky, resp. mobilních robotických platforem. Technicky je realizace plánování pohybu z globální úrovně převedena do posloupnosti akcí na úrovni specifické robotické platformy a definovaného prostředí, včetně omezení. V rámci této práce byla provedena recenze mnoha metod určených pro plánování cest, přičemž hlavním těžištěm byly metody založené na tzv. rychle rostoucích stromech (RRT), prostorovém rozkladu (CD) a využití fuzzy expertních systémů (FES). Dosažené výsledky, resp. prezentované algoritmy, využívají dostupné informace z pracovního prostoru mobilního robotu a jsou aplikovatelné na řešení globální pohybové trajektorie mobilních robotů, resp. k řešení specifických problémů plánování cest s omezením typu úzké koridory či překážky s proměnnou polohou v čase. V práci jsou představeny nové plánovací postupy využívající výhod algoritmů RRT a CD. Navržené metody jsou navíc efektivně rozšířeny s využitím fuzzy expertního systému, který zlepšuje jejich chování. Práce rovněž prezentuje řešení pro plánovací problémy typu identifikace úzkých koridorů, či významných oblastí prostoru řešení s využitím přístupů na bázi dekompozice prostoru. V řešeních jsou částečně zahrnuty sub-optimalizace nalezených cest založené na zkracování nalezené cesty a vyhlazování cesty, resp. nahrazení trajektorie hladkou křivkou, respektující lépe předpokládanou dynamiku mobilního zařízení. Všechny prezentované metody byly implementovány v prostředí Matlab, které sloužilo k simulačnímu ověření efektivnosti vlastních i převzatých metod a k návrhu prostoru řešení včetně omezení (překážky). Získané výsledky byly vyhodnoceny s využitím statistických přístupů v prostředí Minitab a Matlab.
225

Plánování pohybu objektu v 3D prostoru / Path Planning in 3D Space

Němec, František January 2016 (has links)
This paper deals with the problem of object path planning in 3D space. The goal is to create program which allows users to create a scene used for path planning, perform the planning and finally visualize path in the scene. Work is focused on probabilistic algorithms that are described in the theoretical part. The practical part describes the design and implementation of application. Finally, several experiments are performed to compare the performance of different algorithms and demonstrate the functionality of the program.
226

Real-time motion planning of 6 DOF Collaborative Robot

Ahmadi, Seyedhesam January 2022 (has links)
Motion planning is an essential component of an autonomous system. This project aims to design a motion planning module to automate the screwing process of radio units. The goal is to choose and implement a motion planner that provides the speed, precision, and efficiency required for the screwing task on a radio filter with a large number of holes located close to each other. Four control-based motion planners were investigated on a 6 Degrees Of Freedom (DOF) robot arm in Robot Operating System (ROS). The investigated motion planners are Rapidly-exploring Random Trees, The Kinodynamic Motion Planning by Interior-Exterior Cell Exploration (KPIECE), The Path- Directed subdivision Trees (PDST), Expansive Space Trees (EST). All these planners are available in The Open Motion Planning Library (OMPL). The motion planners were implemented on a simulated version of a UR5 robot arm. This simulated model is generated by the MoveIt Setup Assistant, which is the primary tool for creating configuration files for kinematics chains in MoveIt. ROS is the chosen platform to design various control methods and motion planning algorithms. Hence two primary workspaces have been created. These workspaces contain several packages and nodes with multiple tasks such as motion planning, visualization, and data extraction. All the nodes communicate using ROS communication tools such as massages services and action client services. Furthermore, this project covers also test and benchmarking all the mentioned planners to determine which planner provides optimal performance in different environments. The planner’s performance is evaluated by designing two experiments in three benchmarking scenarios. The first test is intended to determine how the planners perform a motion planning task similar to an actual screwing process of a radio filter. The purpose of the second experiment is to investigate how the planners perform as the density of the obstacles increase. The performances of the planners have been analyzed and compared with each other using different benchmarking tools such as the planner arena. Result of this project indicates, KPIECE and EST can outperform the state-of-the- art planner, RRT-Connect in some and metrics, especially in an environment with a low obstacles density. However, RRT-Connect is still superior in more dense and complicated settings. / Rörelseplanering är en viktig komponent i ett automatiserat system. Detta projekt syftar till att designa en rörelseplaneringsmodul för att automatisera skruvningen av radioenheter. Målet är att implementera en rörelseplanerare som kan frambringa den hastighet, noggrannhet och effektivitet som krävs för en automatiserad skruvdragare. Skruvdragarens uppgift är att skruva ett antal hål placerade nära varandra på en radiofilter. Denna upsats har undersökt fyra kontrollbaserade rörelseplanerare på en 6 Degrees Of Freedom (DOF) robotarm med hjälp av Robot Operating System (ROS). De undersökta rörelseplanerarna är Rapidly-Exploring Random Trees, The Kinodynamic Motion Planning by Interior-Exterior Cell Exploration (KPIECE), The Path- Directed subdivision Trees (PDST) och Expansive Space Trees (EST)som är tillgängliga i Open Motion The Open Motion Planning Library (OMPL). Planerarna implementeras på en simulerad UR5-robotarm, genererad av MoveIt Setup Assistant, som är det primära verktyget för att skapa konfigurationsfiler för kinematikkedjor i MoveIt. ROS är den valda plattformen för att designa styrmetoder och rörelseplaneringens algoritmer vilket medför att två arbetsytor har skapats. Dessa arbetsytor innehåller flera paket och noder med flera uppgifter bland annat rörelseplanering, visualisering och dataextraktion. Alla noder kommunicerar med varandra genom ROS kommunikationsverktyg liksom massagetjänster och action-client tjänster. Detta projekt omfattar även benchmarkingäv alla ovannämnda planerare för att avgöra vilken of dessa planerare kan åstadkomma en optimal prestanda i olika miljöer. Planerarens prestanda utvärderas genom att designa två experiment i tre benchmarking-scenarier. Det första testet är avsett att bestämma hur en planerare utför en rörelseplaneringsuppgift vilket liknar en verklig skruvprocess för en radioenhet. Andra experimentet är att undersöka hur planerarna presterade när tätheten av hindren ökar. Planerarnas prestationer har analyserats och jämförts med varandra med hjälp av olika benchmarkingverktyger, till exemple Planer Arena. Enligt resultatet av detta projekt kan KPIECE och EST prestera bättre jämfort med den senaste planeraren RRT-Connect i vissa områden, särskilt i ett miljö med låg hindertäthet. RRT-Connect är dock fortfarande överlägsen i mer täta och komplicerade miljöer.
227

Selected Aspects of Navigation and Path Planning in Unmanned Aircraft Systems

Wzorek, Mariusz January 2011 (has links)
Unmanned aircraft systems (UASs) are an important future technology with early generations already being used in many areas of application encompassing both military and civilian domains. This thesis proposes a number of integration techniques for combining control-based navigation with more abstract path planning functionality for UASs. These techniques are empirically tested and validated using an RMAX helicopter platform used in the UASTechLab at Linköping University. Although the thesis focuses on helicopter platforms, the techniques are generic in nature and can be used in other robotic systems. At the control level a navigation task is executed by a set of control modes. A framework based on the abstraction of hierarchical concurrent state machines for the design and development of hybrid control systems is presented. The framework is used to specify  reactive behaviors and for sequentialisation of control modes. Selected examples of control systems deployed on UASs are presented. Collision-free paths executed at the control level are generated by path planning algorithms.We propose a path replanning framework extending the existing path planners to allow dynamic repair of flight paths when new obstacles or no-fly zones obstructing the current flight path are detected. Additionally, a novel approach to selecting the best path repair strategy based on machine learning technique is presented. A prerequisite for a safe navigation in a real-world environment is an accurate geometrical model. As a step towards building accurate 3D models onboard UASs initial work on the integration of a laser range finder with a helicopter platform is also presented. Combination of the techniques presented provides another step towards building comprehensive and robust navigation systems for future UASs.
228

Prise de décision et planification de trajectoire pour les véhicules coopératifs et autonomes / Decision-based motion planning for cooperative and autonomous vehicles

Altché, Florent 30 August 2018 (has links)
Le déploiement des futurs véhicules autonomes promet d'avoir un impact socio-économique majeur, en raison de leur promesse d'être à la fois plus sûrs et plus efficaces que ceux conduits par des humains. Afin de satisfaire à ces attentes, la capacité des véhicules autonomes à planifier des trajectoires sûres et à manœuvrer efficacement dans le trafic sera capitale. Cependant, le problème de planification de trajectoire au milieu d'obstacles statiques ou mobiles a une combinatoire forte qui est encore aujourd'hui problématique pour les meilleurs algorithmes.Cette thèse explore une nouvelle approche de la planification de mouvement, basée sur l'utilisation de la notion de décision de conduite comme guide pour structurer le problème de planification en vue de faciliter sa résolution. Cette approche peut trouver des applications pour la conduite coopérative, par exemple pour coordonner plusieurs véhicules dans une intersection non signalisée, ainsi que pour la conduite autonome où chaque véhicule planifie sa trajectoire. Dans le cas de la conduite coopérative, les décisions correspondent au choix d'un ordonnancement des véhicules qui peut être avantageusement encodé comme un graphe. Cette thèse propose une représentation similaire pour la conduite autonome, où les décisions telles que dépasser ou non un véhicule sont nettement plus complexes. Une fois la décision prise, il devient aisé de déterminer la meilleure trajectoire y correspondant, en conduite coopérative comme autonome. Cette approche basée sur la prise de décision peut permettre d'améliorer la robustesse et l'efficacité de la planification de trajectoire, et ouvre d'intéressantes perspectives en permettant de combiner des approches mathématiques classiques avec des techniques plus modernes d'apprentissage automatisé. / The deployment of future self-driving vehicles is expected to have a major socioeconomic impact due to their promise to be both safer and more traffic-efficient than human-driven vehicles. In order to live up to these expectations, the ability of autonomous vehicles to plan safe trajectories and maneuver efficiently around obstacles will be paramount. However, motion planning among static or moving objects such as other vehicles is known to be a highly combinatorial problem, that remains challenging even for state-of-the-art algorithms. Indeed, the presence of obstacles creates exponentially many discrete maneuver choices, which are difficult even to characterize in the context of autonomous driving. This thesis explores a new approach to motion planning, based on using this notion of driving decisions as a guide to give structure to the planning problem, ultimately allowing easier resolution. This decision-based motion planning approach can find applications in cooperative driving, for instance to coordinate multiple vehicles through an unsignalized intersection, as well as in autonomous driving where a single vehicle plans its own trajectory. In the case of cooperative driving, decisions are known to correspond to the choice of a relative ordering for conflicting vehicles, which can be conveniently encoded as a graph. This thesis introduces a similar graph representation in the case of autonomous driving, where possible decisions -- such as overtaking the vehicle at a specific time -- are much more complex. Once a decision is made, planning the best possible trajectory corresponding to this decision is a much simpler problem, both in cooperative and autonomous driving. This decision-aware approach may lead to more robust and efficient motion planning, and opens exciting perspectives for combining classical mathematic programming algorithms with more modern machine learning techniques.
229

Intelligent Drone Swarms : Motion planning and safe collision avoidance control of autonomous drone swarms

Gunnarsson, Hilding, Åsbrink, Adam January 2022 (has links)
The use of unmanned aerial vehicles (UAV), so-called drones, has been growingrapidly in the last decade. Today, they are used for, among other things, monitoring missions and inspections of places that are difficult for people to access. Toefficiently and robustly execute these types of missions, a swarm of drones maybe used, i.e., a collection of drones that coordinate together. However, this introduces new requirements on what solutions are used for control and navigation. Two important aspects of autonomous navigation of drone swarms are formationcontrol and collision avoidance. To manage these problems, we propose four different solution algorithms. Two of them use leader-follower control to keep formation, Artificial PotentialField (APF) for path planning and Control Barrier Function (CBF)/ExponentialControl Barrier Function (ECBF) to guarantee that the control signal is safe i.e.the drones keep the desired safety distance. The other two solutions use an optimal control problem formulation of a motion planning problem to either generate open-loop or closed-loop trajectories with a linear quadratic regulator (LQR)controller for trajectory following. The trajectories are optimized in terms of timeand formation keeping. Two different controllers are used in the solutions. Oneof which uses cascade PID control, and the other uses a combination of cascadePID control and LQR control. As a way to test our solutions, a scenario is created that can show the utilityof the presented algorithms. The scenario consists of two drone swarms that willtake on different missions executed in the same environment, where the droneswarms will be on a direct collision course with each other. The implementedsolutions should keep the desired formation while smoothly avoiding collisionsand deadlocks. The tests are conducted on real UAVs, using the open sourceflying development platform Crazyflie 2.1 from Bitcraze AB. The resulting trajectories are evaluated in terms of time, path length, formation error, smoothnessand safety.  The obtained results show that generating trajectories from an optimal control problem is superior compared to using APF+leader-follower+CBF/ECBF. However, one major advantage of the last-mentioned algorithms is that decision making is done at every time step making these solutions more robust to disturbancesand changes in the environment.
230

Motion Planning for Aggressive Flights of an Unmanned Aerial Vehicle

Smith, Cornelia, Femic, Filippa January 2022 (has links)
Unmanned aerial vehicles are becoming more popular in today’s society, which results in the rise of laws intended to maintain safety. To abide by these, while allowing the technology to expand, functioning path-planning algorithms are required.This also includes having methods for detecting and managing obstacles. This project aims to improve an existing path-planning algorithm that is based on A* and implemented in Python.The solution consisted of using functions for finding polytopeintersection,as well as optimizing the collision avoidance and the search algorithm. In addition to that, realistic constraints were implemented on the generated trajectory in order to reflect real-life limitations. The results demonstrated that the paths were always feasible, with respect to input and position constraints. The program’s computation time was also reduced up to 89% of the original run-time. There is, however, still room for improvement since the original code generated a shorter path for the three scenarios it was created for. On the other hand,the improved algorithm could handle a new scenario, which the original code failed to do. / Obemannade flygfarkoster blir alltmer vanliga i dagens samhälle, vilket resulterar i uppkomsten av nya lagar ämnade åt att upprätthålla säkerhet. För att förhålla sig till dessa, samtidigt som teknologin tillåts expandera, krävs fungerande vägplaneringsalgoritmer. Där ingår det även att ha metoder för att upptäcka och hantera hinder. Detta projekt syftar till att förbättra en befintlig vägplaneringsalgoritm som är baserad på A* och implenterad i Python. Lösningsmetoden bestod av att använda inbyggda Python-funktioner ämnade åt att finna skärningar mellan polytoper, samt optimera kollisionshantering och sökalgoritmen. Dessutom infördes realistiska krav på den framställda vägen i syfte om att reflektera verlighetens begränsningar. Resultatet visade att vägarna alltid var genomförbara, med avseende på inmatningsoch positionsrelaterade villkor. Programmets beräkningstid hade även reducerats upptill 89% av den ursprungliga körtiden. Det finns dock utrymme för förbättringar då den ursprungliga koden generar en kortare väg för de tre scenarion den tillverkades för. Däremot kinde den förbättrade algoritmen hantera ett nytt scenario, en ursprungliga koden misslyckades med. / Kandidatexjobb i elektroteknik 2022, KTH, Stockholm

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