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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.
1

Fractional Order Controller for Quadcopter Subjected to Ground Effect

Mirghasemi, Seyed Alireza 28 May 2019 (has links)
Although the concept of fractional calculus was known for centuries, it was not considered in engineering due to the lack of implementation tools and acceptable performance of integer order models and control. However, recently, engineers and researchers started to investigate the potentially high performance of fractional calculus in various fields among which are acoustics, conservation of mass, diffusion equation and specifically in this thesis control theory. The intention of this thesis is to analyze the relative performance of fractional versus integer order PID controller for a quadcopter. Initially, the dynamics of the quadcopter is presented with additional consideration of the ground effect and torque saturation. Then, are introduced the concept of fractional calculus and the mathematical tools to be used for modeling fractional order controller. Finally, the performance of the fractional order controller is evaluated by comparing it to an integer order controller.
2

Stabilization and Control of Unmanned Quadcopter

Jiřinec, Tomáš January 2011 (has links)
Recent development in the fields of MEMS sensors, miniature, energy efficient and very powerful microcontrollers and microprocessors has given the opportunity to build small autonomous flying vehicles. This thesis is studying one type of these vehicles, so called quadrotor. The quadrotor is flying vehicle similar to helicopter but having four rotors which are situated in one plane. Each propeller is actuated by an independently controlled motor. This feature allows to control Euler angles of the quadrotor such as yaw, pitch and roll thus giving the possibility to control quadrotor's position and velocity. The CTU Department of Cybernetics bought such a quadrotor prototype called Linkquad. The goal is to use this prototype for indoor flights using camera vision as a navigation reference. Unfortunately the prototype has no autonomous control loops implemented. The focal point of this thesis is design of a control law for the already mentioned prototype. This leads to other tasks such as an identification of the models 's parameters, creating mathematical nonlinear model, linearization of this model in certain trim points, design and testing of the linear controller and finally implementation and testing using the real system. / <p>Validerat; 20111004 (anonymous)</p>
3

An Experimental Comparison of Student Motivation Between Two Computational Thinking-Based STEM Activities: Vex-Based Automation and Robotics and a Quadcopter Activity

Ortiz, Cory J. 01 August 2018 (has links)
The purpose of this study was to compare student motivation between two junior high level computational thinking based STEM curricular activities. These two activities were a newly developed quadcopter based curriculum and a VEX based curricular activity developed for Project Lead the Way’s Gateway to Technology – Automation and Robotics course. Student motivation was assessed using an assessment called My Class Activities which broke motivation into four constructs: interest, challenge, choice, and enjoyment. This study assessed students in three schools in a northern Utah school district. Students were assessed after receiving each curriculum. Assessment responses were then coded and analyzed. The results of this study suggested that though the junior high VEX curriculum was more challenging and offered students more choice than the quadcopter curriculum, the teacher delivering the curriculum had more to do with student motivation.
4

Development of a Wireless Video Transfer System for Remote Control of a Lightweight UAV / Utveckling av ett trådlöst videoöverföringssystem för fjärrstyrning av en minimal obemannad luftfarkost

Tosteberg, Joakim, Axelsson, Thomas January 2012 (has links)
A team of developers from Epsilon AB has developed a lightweight remote controlledquadcopter named Crazyflie. The team wants to allow a pilot to navigate thequadcopter using video from an on-board camera as the only guidance. The masterthesis evaluates the feasibility of mounting a camera module on the quadcopter andstreaming images from the camera to a computer, using the existing quadcopterradio link. Using theoretical calculations and measurements, a set of requirementsthat must be fulfilled for such a system are identified. Using the requirementsas a basis, various camera products are investigated and the findings presented.A design to fulfill the requirements, using the found products, is proposed. Theproposed design is then implemented and evaluated. It is found that the Crazyflie system has the resources necessary to transferan image stream with the quality required for navigation. Furthermore, theimplementation is found to provide the required functionality. From the evaluationseveral key factors of the design that can be changed to further improve theperformance of an implementation are identified. Ideas for future work andimprovements are proposed and possible alternative approaches are presented.
5

Autonomous Control of Advanced Multirotor Unmanned Aerial Systems

Kumar, Rumit 24 May 2022 (has links)
No description available.
6

Perching Using a Quadrotor with Onboard Sensing

Goldin, Jeremy C 01 May 2011 (has links)
This thesis presents an implementation of autonomous indoor perching using only onboard sensors on a low-cost, custom-built quadrotor. The perching aggressive maneuver is representative of a class of control problems for aerobatics that requires an agile and robust control system for maneuvering accurately at high speeds. Such research extends the typical functionality of micro air vehicles (MAV) from low speed and stationary observation to dynamic aerobatic transitions for broader operational capabilities including confined landings and evasive maneuvering. To achieve this, three major challenges are overcome: precise and real-time positioning, sensing of the perch and path to the perch, and control methods for robust and accurate tracking at high speeds. Navigation in unstructured, global positioning system (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 locate the pathway for the maneuver and the perch, simulating sensing of the actual perch, for perching without prior knowledge of the location of the perch. The full physical system architecture is covered in detail, indicating the components and integration necessary to obtain effective aggressive control of an inexpensive quadrotor. The difficulties of attitude stabilization on noisy and lower-quality sensors are successfully addressed so that the air vehicle can be treated as a simple second-order system for the purposes of navigation and response to dynamic maneuvering commands. The system utilizes nested controllers for attitude stabilization, vision-based navigation, and perching guidance, with the navigation controller implemented using novel nonlinear saturation control within a Proportional-Integral-Derivative (PID) structure. The quadrotor is therefore able to autonomously sense the perch, reach initial high speeds for obtaining rapid deceleration from aerodynamic effects, dynamically transition to a high angle of attack post-stall configuration, and make a low-speed accurate landing on an inclined surface, using only onboard sensors.
7

Flying Penguins : Building and Evaluating the Viability of a Linux-based Drone

Mårtensson, Anders January 2016 (has links)
Traditional quadcopter flight controllers use microcontrollers to run the code that keeps the drone in the air, and when more processing power or versatility is needed the same microcontrollers are used in tandem with Linux-based single-board computers. It would be cheaper and reduce complexity if the single-board computer could entirely replace the microcontrollers. We investigate whether it is possible to run a quadcopter using a Linux single-board computer as the flight controller, with no microcontrollers and otherwise the same hardware as used in hobby-grade quadcopters. We attempt to find out what the potential issues are and how to get around or mitigate them. To test it, a quadcopter will be built from hobby parts and the flight control software to be run on the flight controller will be developed. More specifically, the pulse-width modulation signals to the motor speed controllers are checked for stability and various methods of acquiring the radio control input in the form of pulse-width modulation signals are evaluated. The speed at which the flight control software is running is measured under different circumstances—with and without load and with and without mitigative measures active. We conclude that it was not possible to run a quadcopter using only the chosen Linux SBC as flight controller. The reason was because we could not accurately measure the radio control input, although there may be other additional issues. We did find that CPU time did not seem to be an issue even when an artificial stress was placed on the system, despite not being a real time system, and even less of an issue when the mitigation techniques discussed were applied.
8

Realizace vrtulníku se čtyřmi rotory / Quadrocopter realization

Pekarovič, Ján January 2014 (has links)
This thesis deals with the design of a helicopter with four rotors known as quadcopter. It describes the principles of operation and existing modifications. Part of the work is the selection of a suitable frame, remote control set, engines and propellers, battery, sensors for stabilization and detection of obstacles and microcontroller for their operation. The paper presents the concept of the specific copter design, design and simulation of printed circuit boards to their self-production, activation and testing. The final part of the thesis includes an economic assessment of the project and its comparison with competitors.
9

Physics-Based Neural Networks for Modeling & Control of Aerial Vehicles

Breese, Bennett January 2021 (has links)
No description available.
10

Transition of Quadcopter Box-wing UAV between Cruise and VTOL Modes

Gupta, Gaurang 02 November 2018 (has links)
No description available.

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