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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.
11

Simulace kooperativního dohledu pomocí bezpilotních letounů za použití platforem Pogamut a USARsim / Simulation of Multi-UAV Cooperative Surveillance Using Pogamut and USARSim

Dufek, Jan January 2014 (has links)
The main objective of this thesis is to introduce a simulation platform, which has been developed utilizing Pogamut and USARSim, for cooperative aerial surveillance using multiple unmanned aerial vehicles (UAVs). The graphical user interface (GUI) of the simulator contains the automatically created bird's eye view of a 3D virtual environment. This is used to enter locations and parameters of objects (UAVs, charging stations and areas) and also to visualize the process of a simulation. The thesis proposes a system for the analysis of the quality of surveillance, whose results are presented in the GUI in the form of a time graph and a heat map. Part of the proposed platform is a UAV objective-based control system including charging stations scheduling. A total of seven algorithms for cooperative surveillance has been implemented, tested in three different scenarios and analyzed for coverage quality. Powered by TCPDF (www.tcpdf.org)
12

An Autonomous Unmanned Aerial Vehicle-Based Imagery System Development and Remote Sensing Images Classification for Agricultural Applications

Han, Yiding 01 December 2009 (has links)
This work concentrates on the topic of remote sensing using a multispectral imag-ing system for water management and agriculture applications. The platform, which is alight-weight inexpensive runway-free unmanned aerial vehicle (UAV), namely, AggieAir, ispresented initially. A major portion of this work focuses on the development of a light-weight multispectral imager payload for the AggieAir platform, called GhostFoto. Theimager is band-recongurable, covering both visual red, green, and blue (RGB) and nearinfrared (NIR) spectrum, and interfaced with UAV on-board computer. The developmentof the image processing techniques, which are based on the collected multispectral aerialimages, is also presented in this work. One application is to perform fully autonomous rivertracking for applications such as river water management. Simulation based on aerial mul-tispectral images is done to demonstrate the feasibility of the developed algorithm. Othereort is made to create a systematic method to generate normalized difference vegetationindex (NDVI) using the airborne imagery. The GhostFoto multispectral imaging systembased on AggieAir architecture is proven to be an innovative and useful tool.
13

Omkonstruktion och arkitekturbyte av autopilot för obemannade farkoster

Andersson, Erik January 2012 (has links)
This thesis has been written at Linköping University for the company Instrument Control Sweden AB (ICS). ICS is a small company located in Linköping that develops software and hardware for Unmanned Aerial Vehicles, UAV. At present, ICS has a fully functional autopilot called EasyPilot but they want to reduce the autopilot’s size to make it more attractive. The purpose of this thesis was to investigate if it was possible to reduce the size of the autopilot and how, in that case, it would be done. It was also necessary to examine whether the old processors should be replaced by new ones and how hard it would be to convert the old software to these new processors. To succeed with the goals many of the old components had to be changed for new, smaller ones. Some less necessary parts were also completely removed. The results showed that the size could be reduced quite a bit, exactly how much is hard to say since no PCB-layout were done. By doing some programming tests on the new components it could be shown that some parts of the old code could be reused on the new design. It was mainly algorithms and other calculations. However, a lot of new code still had to be written in order to successfully convert the old software to the new hardware.
14

Use of Micro Unmanned Aerial Vehicles in Transportation Infrastructure Condition Surveys

Hart, William Scott 2010 December 1900 (has links)
This thesis provides an assessment of the effectiveness of micro unmanned aerial vehicles (MUAVs) as a tool for collecting condition data for transportation infrastructure based on multiple field experiments. The primary experiment entails performing a level of service (LOS) condition assessment on multiple roadside sample units at various locations across the state of Texas. A secondary field experiment entails performing a pavement condition index (PCI) survey on airfield pavements. The condition of these sample units were assessed twice: onsite (i.e., ground truth) and by observing digital images (still and video) collected via a MUAV. The results of these surveys are then analyzed to determine if there are statistically significant differences in the standard deviation and mean values of the condition ratings. This study shows that in favorable site conditions, the MUAV demonstrates promise for improving current roadway inspection methods. However, limitations of the MUAVs field performance show that there is need for improvement in this technology before it can be implemented.
15

SIMULATION AND CONTROL OF A QUADROTOR UNMANNED AERIAL VEHICLE

Schmidt, Michael David 01 January 2011 (has links)
The ANGEL project (Aerial Network Guided Electronic Lookout) takes a systems engineering approach to the design, development, testing and implementation of a quadrotor unmanned aerial vehicle. Many current research endeavors into the field of quadrotors for use as unmanned vehicles do not utilize the broad systems approach to design and implementation. These other projects use pre-fabricated quadrotor platforms and a series of external sensors in a mock environment that is unfeasible for real world use. The ANGEL system was designed specifically for use in a combat theater where robustness and ease of control are paramount. A complete simulation model of the ANGEL system dynamics was developed and used to tune a custom controller in MATLAB and Simulink®. This controller was then implemented in hardware and paired with the necessary subsystems to complete the ANGEL platform. Preliminary tests show successful operation of the craft, although more development is required before it is deployed in field. A custom high-level controller for the craft was written with the intention that troops should be able to send commands to the platform without having a dedicated pilot. A second craft that exhibits detachable limbs for greatly enhanced transportation efficiency is also in development.
16

A COMMUNICATION LINK RELIABILITY STUDY FOR SMALL UNMANNED AERIAL VEHICLES

Mylin, Alicia K. 01 January 2007 (has links)
Dependable communication links for unmanned aerial vehicles (UAV) are crucial to operational reliability and mission success. This study is focused on evaluating the probability of successful communication links for small UAVs. A program based on the Friis Transmission Equation was developed to calculate the power received in a line-of-sight communication link. The program was used to evaluate the probability of success for a variety of flight pa
17

Návrh bezpilotního letadla pro odchyt hmyzího aeroplanktonu / Design of unmanned aerial vehicle for insect aeroplankton collection

Hošek, Vlastimil January 2017 (has links)
Ke studiu migrace hmyzu a jiných členovců unášených větrnými proudy je výhodné moci sbírat jejich vzorky za letu. Použití bezpilotního letadla s pastí by mohlo být dobrou cestou, jak toho dosáhnout. Tato metoda byla zkoumána a bylo navrženo bezpilotní letadlo v podobě bezocasého dvojploŠníku s pastí umístěnou mezi křídly.
18

Design of an unmanned aerial system for the detection of dangerous areas during fires

Daviran, Richard, Quispe, Grimaldo, Chavez-Arias, Heyul, Raymundo-Ibanez, Carlos, Dominguez, Francisco 01 November 2019 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / This article presents the design of an unmanned aerial vehicle manufactured in aramid, through the use of sensors and actuators for flight stabilization, capturing the images through a thermal imager and its wireless transmission for ground processing for application in the social security area used in fire accidents. The work shows that it is feasible to use the aramid material for the construction of the prototype, since it is a high temperature resistant material, also the integration of neural networks for semi-automatic flight control. The results of this research will serve to develop more advanced control devices, with simple components and controls so that people with technological limitations can use it, so that they can save lives in danger, that of their colleagues or themselves. / Revisión por pares
19

Nonlinear six degree-ofreedom simulator for a small unmanned aerial vehicle

Edwards, Christopher Doyle 01 May 2010 (has links)
Aircraft modeling and simulation have become increasingly important in the areas of pilot training, safety and aircraft design, especially for unmanned aerial vehicles (UAVs). A userriendly, easily expandable, nonlinear six degree-ofreedom aircraft simulator for the Xipiter X-2C Xawk UAV was created to address these issues. The simulator will allow pilots to have an opportunity to train and gain experience in flying the aircraft even before it leaves the ground. In addition, it will allow for design modifications or new aircraft designs to be evaluated before time and money are spent on their implementation. This work can also serve as the basis for the development of control systems for the aircraft, such as a control augmentation system or autopilot.
20

System Identification of an Unmanned Tailsitter Aircraft

Edwards, Nathan W. 01 August 2014 (has links) (PDF)
The motivation for this research is the need to improve performance of the autonomous flight of a tailsitter UAV. Tailsitter aircraft combine the hovering and vertical take-off and landing capability of a rotorcraft with the long endurance flight capability of a fixed-wing aircraft. The particular aircraft used in this research is the V-Bat, a tailsitter UAV with a conventional wing and the propeller and control surfaces located within a ducted-fan tail assembly. This research focuses on identifying the models and parameters of the V-Bat in hover and level flight as a basis for the design of the control systems for hover, level, and transition modes of flight.Models and parameters were identified from experimental data. Wind-tunnel tests, bench tests, and flight tests were performed in a variety of flight conditions. Wind tunnel tests yielded force and moment coefficients over the full flight envelope of the V-Bat. Models and parameters for longitudinal, lateral, and hover flight are presented. Bench tests were conducted to enhance understanding about the ducted-fan propulsion system and the effectiveness of the control surfaces. The thrust characteristics of the ducted fan were measured. Control derivatives were derived from force and moment measurements. Flight tests were completed to obtain dynamic models of the V-Bat in hover flight. Using frequency-domain system identification methods, frequency-response and transfer function models of roll, pitch, and yaw responses to aileron, elevator, and rudder control input were derived.The results obtained from these experimental tests were used to identify models and parameters of the V-Bat aircraft, giving insight into its behavior and enhancing the control analysis and simulation capabilities for this aircraft, thus providing the increased levels of understanding needed for autonomous flight.

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