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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.
31

Řízení létajících robotů / Control of Quadrotor

Tesáček, Zdeněk January 2010 (has links)
This master’s thesis deals with the design and optimization of the quadrotor stabilization control. The basic physical properties and technical aspects of this specific device are illustrated using the NANOKOPTER platform. Dedicated mathematical model of quadrotor was implemented in MATLAB/Simulink environment to emulate the behavior and characteristics of real quadrotor. Based on this model a feasible method of stabilization control by means of state controller was conceived and developed. The proposed solution utilizing state controller was incorporated into the stabilization control procedures of the NANOKOPTER testing platform and its functionality successfully verified during field trials.
32

Návrh čtyř-rotorového vznášedla / Design of Quadrocopter

Uhlíř, Václav January 2013 (has links)
This student paper discusses basic concept of quadrocopter for purpose of academic platform for testing and development. Paper includes basic overview of construction, stabilization and controlling of quadrocopter. As result of this paper is presented concept of quadrocopter and its constructed prototype with included software console for wireless control under Android system.
33

Autonomous Aerial Void Exploration

Vidmark, Emil January 2020 (has links)
Deploying robots in unknown and complex areas for inspection tasks is becoming a real need for various application scenarios. Recently, there has been an increasing interest to develop and use autonomous aerial robots in environments such as urban voids and subterranean mine tunnels, aiming to decrease the human presence in dangerous or inaccessible areas. These areas are characterized by complete darkness and narrow tunnels, where the ground can often be rough and not traversible for mobile vehicles, thus the developments focus on Micro Aerial Vehicles (MAVs). MAVs are mechanically simple and agile platforms that can navigate through cluttered areas and have the potential to perform complex exploration tasks when equipped with proper onboard sensors. One of the key milestones in the development of autonomous robots is self-exploration. The definition of self-exploration according to [7] is "the act of moving through an unknown environment while building a map that can be used for subsequent navigation". By reaching this milestone, robots would be freed from the limitation of requiring already existing maps for navigation. In this thesis, a frontier-based exploration algorithm is established and evaluated to understand how such method could be used to reach the self-exploration milestone. By marking the border between what is known and unknown the method is able to determine the next desired position for the robot to expand the map. The resulting algorithm, together with a path planning method and 3-dimensional mapping framework, the method was tested and examined in simulated environments with different levels of complexity.
34

Controle de estabilização de voo de VANTs quadrirrotores : modelagem, controle, simulação e prototipagem /

Lima, Fernando Mascagna Bittencourt January 2020 (has links)
Orientador: Átila Madureira Bueno / Resumo: O controle de estabilização do voo de VANTs (veículos aéreos não tripulados) quadrirrotores abrange diversas áreas do conhecimento da engenharia, tais como mecânica, eletrônica e computação. O objetivo deste trabalho é o desenvolvimento de diferentes controladores para tal estabilização. Diferentes controladores (lineares e não lineares) foram desenvolvidos e avaliados a fim de estabelecer um comparativo entre os resultados obtidos para cada um e determinar qual deles é o mais eficiente para diferentes condições de voo. Para tal desenvolvimento, um modelo matemático do VANT em questão foi obtido a fim de possibilitar o projeto dos controladores. Este modelo utilizou os parâmetros de um quadrirrotor real que também foi desenvolvido neste projeto para validação da eficiência dos controladores desenvolvidos. O protótipo foi projetado de tal forma a possuir uma autonomia de voo suficiente para realização dos testes, resistência mecânica a todos as condições que pode ser exposto durante o voo, tais como vento e vibrações geradas, e ser controlável. Para a validação da eficiência dos controladores desenvolvidos, foram realizadas tanto simulações quanto testes aplicados ao protótipo fixado a uma estrutura giroscópica de testes. Para a realização das simulações, a planta a ser controlada foi o modelo encontrado anteriormente. Os resultados das simulações mostraram que todos os controladores desenvolvidos são capazes de estabilizar o voo do quadrirrotor. Já os testes aplicados ao prot... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The flight stabilization control of quadrotor UAVs (unmanned aerial vehicles) covers several areas of engineering knowledge, such as mechanics, electronics and computing science. The objective of this work is the development of different controllers for such stabilization. Different controllers (linear and non-linear) were developed and evaluated in order to establish a comparison between the results obtained for each one and to determine which one is the most efficient for different flight conditions. For such development, a mathematical model of the UAV in question was obtained in order to enable the design of the controllers. This model used the parameters of a real quadrirotor that was also developed in this project to validate the efficiency of the developed controllers. The prototype was designed to have sufficient flight autonomy to carry out the tests, mechanical resistance to all conditions that can be exposed during the flight, such as wind and generated vibrations, and be controllable. In order to validate the efficiency of the developed controllers, simulations and tests were applied to the prototype attached to a gyroscopic test structure. To perform the simulations, the plant to be controlled was the model previously found. The results of the simulations showed that all the controllers developed are capable of stabilizing the flight of the quadrotor. The tests applied to the prototype, on the other hand, suffered non-modeled interferences such as inertia couplin... (Complete abstract click electronic access below) / Mestre
35

Autonomous Aerial Manipulations Using a Quadrotor

Ghadiok, Vaibhav 01 August 2011 (has links)
This paper presents an implementation of autonomous indoor aerial gripping using a low-cost, custom-built quadrotor. Such research extends the typical functionality of micro air vehicles (MAV) from passive observation and sensing to dynamic interaction with the environment. To achieve this, three major challenges are overcome: precise positioning, sensing and manipulation of the object, and stabilization in the presence of disturbance due to interaction with the object. Navigation in both indoor and outdoor unstructured, Global Positioning System-denied (GPS-denied) environments is achieved using a visual Simultaneous Localization and Mapping (SLAM) algorithm that relies on an onboard monocular camera. A secondary camera, capable of detecting infrared light sources, is used to estimate the 3D location of the object, while an under-actuated and passively compliant manipulator is designed for effective gripping under uncertainty. The system utilizes nested ProportionalIntegral-Derivative (PID) controllers for attitude stabilization, vision-based navigation, and gripping. The quadrotor is therefore able to autonomously navigate, locate, and grasp an object, using only onboard sensors.
36

Quadrotor UAV Flight Control with Integrated Mapping and Path Planning Capabilities

Gauthier, Jason A. January 2020 (has links)
No description available.
37

Modeling, Parameter Estimation, and Navigation of Indoor Quadrotor Robots

Quebe, Stephen C. 29 April 2013 (has links) (PDF)
This thesis discusses topics relevant to indoor unmanned quadrotor navigation and control. These topics include: quadrotor modeling, sensor modeling, quadrotor parameter estimation, sensor calibration, quadrotor state estimation using onboard sensors, and cooperative GPS navigation. Modeling the quadrotor, sensor modeling, and parameter estimation are essential components for quadrotor navigation and control. This thesis investigates prior work and organizes a wide variety of models and calibration methods that enable indoor unmanned quadrotor flight. Quadrotor parameter estimation using a particle filter is a contribution that extends current research in the area. This contribution is novel in that it applies the particle filter specifically to quadrotor parameter estimation as opposed to quadrotor state estimation. The advantages and disadvantages of such an approach are explained. Quadrotor state estimation using onboard sensors and without the aid of GPS is also discussed, as well as quadrotor pose estimation using the Extended Kalman Filter with an inertial measurement unit and simulated 3D camera updates. This is done using two measurement updates: one from the inertial measurement unit and one from the simulated 3D camera. Finally, we demonstrate that when GPS lock cannot be obtained by an unmanned vehicle individually. A group of cooperative robots with pose estimates to one anther can exploit partial GPS information to improve global position estimates for individuals in the group. This method is advantageous for robots that need to navigate in environments where signals from GPS satellites are partially obscured or jammed.
38

Optimal Path Planning and Control of Quadrotor Unmanned Aerial Vehicle for Area Coverage

Fan, Jiankun January 2014 (has links)
No description available.
39

Controlador nebuloso para estabilidade de quadrotores

Sales, Diego Câmara 26 July 2014 (has links)
Submitted by Adriely Bruce (adriely_bruce@hotmail.com) on 2016-12-16T13:13:00Z No. of bitstreams: 1 Dissertação - Diego Câmara Sales.pdf: 3202633 bytes, checksum: b132b1fefafdda85faf38c42f7092ae2 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-12-22T15:15:35Z (GMT) No. of bitstreams: 1 Dissertação - Diego Câmara Sales.pdf: 3202633 bytes, checksum: b132b1fefafdda85faf38c42f7092ae2 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-12-22T15:16:44Z (GMT) No. of bitstreams: 1 Dissertação - Diego Câmara Sales.pdf: 3202633 bytes, checksum: b132b1fefafdda85faf38c42f7092ae2 (MD5) / Made available in DSpace on 2016-12-22T15:16:44Z (GMT). No. of bitstreams: 1 Dissertação - Diego Câmara Sales.pdf: 3202633 bytes, checksum: b132b1fefafdda85faf38c42f7092ae2 (MD5) Previous issue date: 2014-07-26 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / Nowadays kind quadrotor helicopters are becoming popular in developing research in unmanned aerial vehicles UAV, for its ability to planar and vertical landing in hard to reach places. The control of most of these vehicles is based on physical or experimental dynamic models, and may have a high cost due to the time of project development. In this work is presented the stability control using fuzzy logic, which eliminates the need for a dynamic model for the controller design. Using the least amount of linguistic rules in order to enable the implementation of the controller in embedded systems with low computational capacity. / Hoje em dia os helicópteros do tipo quadrotor estão se tornando populares no desenvolvimento de pesquisas em veículos aéreos não tripulados VANT, pela sua capacidade de pouso vertical e de planar em locais de difícil acesso. O controle da maioria destes veículos é baseado em modelos dinâmicos físicos ou experimentais, podendo apresentar um alto custo devido ao tempo de desenvolvimento do projeto. Neste trabalho é apresentado o controle de estabilidade de um quadrotor utilizando lógica fuzzy, que dispensa a necessidade de um modelo dinâmico para o projeto do controlador. Utilizando a menor quantidade de regras linguísticas com o intuito de viabilizar a implementação do controlador em sistemas embarcados de baixa capacidade computacional simplificando o desenvolvimento do controlador de estabilidade do sistema proposto.
40

Multi-Fidelity Study of Aerodynamics and Aeroacoustics Characteristics of a Quadrotor Biplane Tailsitter

Heydari, Morteza 05 1900 (has links)
Recent advances in manufacturing and growing concerns on the sustainability of aviation environment have led to a remarkable interest in electrical unmanned aerial systems (UASs) in the past decade. Among various UAS types, the newly designed quadrotor biplane tailsitter class is capable of delivering a wide range of civilian and military tasks, relying on its Vertical Take-Off and Landing (VTOL) capability as well as great maneuverability. Nevertheless, as such UASs employ rotors to generate thrust, and wings to generate lift, and operate at less-understood low to mid-Reynolds flow regime, they experience complicated flight aerodynamics with a noise generation mechanism which is different from common aircrafts. The present work aims at addressing this knowledge gap by studying the aerodynamics and aeroacoustics of a UAS of this type designed by the Army Research Lab. High-fidelity computational fluid dynamics (CFD) simulations are carried out for a wide range of operating conditions to understand the physics involved in the UAS aerodynamics and characterize its performance. Relying on the CFD results, a physics-informed reduced order model (ROM) is developed based on machine learning algorithms, to predict the propellers effects on the wings and calculate the dominant loads. The results of this study indicate that the UAS aerodynamics is significantly influenced by the propeller-wing interaction, which makes it challenging to estimate the loads by classic methods. The proposed physics-informed ROM shows a promising performance based on its computational cost and accuracy. Additionally, it is found that the aeroacoustics of the UAS is ruled by a two-way mechanism through which the propellers and the structure impose unsteadiness on each other.

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