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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.
21

Dynamic Modeling, Guidance, And Control Of Homing Missiles

Ozkan, Bulent 01 September 2005 (has links) (PDF)
DYNAMIC MODELING, GUIDANCE, AND CONTROL OF HOMING MISSILES &Ouml / ZKAN, B&uuml / lent Ph. D., Department of Mechanical Engineering Supervisor: Prof. Dr. M. Kemal &Ouml / ZG&Ouml / REN Co-Supervisor: Dr. G&ouml / kmen MAHMUTYAZICIOgLU September 2005, 236 pages In this study, the dynamic modeling, guidance, and control of a missile with two relatively rotating parts are dealt with. The two parts of the missile are connected to each other by means of a roller bearing. In the first part of the study, the governing differential equations of motion of the mentioned missile are derived. Then, regarding the relative rotation between the bodies, the aerodynamic model of the missile is constructed by means of the Missile Datcom software available in T&Uuml / BiTAK-SAGE. After obtaining the required aerodynamic stability derivatives using the generated aerodynamic data, the necessary transfer functions are determined based on the equations of motion of the missile. Next, the guidance laws that are considered in this study are formulated. Here, the Linear Homing Guidance and the Parabolic Homing Guidance laws are introduced as alternatives to the Proportional Navigation Guidance law. On this occasion, the spatial derivation of the Proportional Navigation Guidance law is also done. Afterwards, the roll, pitch and yaw autopilots are designed using the determined transfer functions. As the roll autopilot is constructed to regulate the roll angle of the front body of the missile which is the controlled part, the pitch and yaw autopilots are designed to realize the command signals generated by the guidance laws. The guidance commands are in the form of either the lateral acceleration components or the flight path angles of the missile. Then, the target kinematics is modeled for a typical surface target. As a complementary part of the work, the design of a target state estimator is made as a first order fading memory filter. Finally, the entire guidance and control system is built by integrating all the models mentioned above. Using the entire system model, the computer simulations are carried out using the Matlab-Simulink software and the proposed guidance laws are compared with the Proportional Navigation Guidance law. The comparison is repeated for a selected single-body missile as well. Consequently, the simulation results are discussed and the study is evaluated.
22

Missile autopilot design using a gain scheduling technique

White, David Paul January 1994 (has links)
No description available.
23

Stabilita a řiditelnost experimentálního letounu VUT 001 Marabu / Stability and Manoeuvrability of Experimental Aircraft VUT 001 Marabu

Marešová, Eva January 2009 (has links)
This diploma thesis deals with a stability and manoeuvrability of experimental aircraft VUT 001 MARABU. It contains calculation of aerodynamic stability derivations and other data necessary for evaluation of static and dynamic stability. Assessment of convenient autopilot.
24

The Development of an FPGA-based Autopilot for Unmanned Aerial Vehicles

Cheng, Quan 01 January 2006 (has links)
This work is part of an on-going research project at Virginia Commonwealth University in the field of Unmanned Aerial Vehicles (UAVs). The purpose of this thesis project is to port the previous generation of UAV autopilot from the Atmel FPSLIC platform to the Xilinx MicroBlaze platform in order to provide a test-bed that will accommodate future research projects. The tasks include porting the software from the AVR processor located on the FPSLIC to the MicroBlaze processor and implementing the hardware peripherals in Xilinx FPGA.The UAV equipped with the new autopilot can autonomously navigate through pre-defined waypoints and transmit the collected data back to the ground base station for analysis.
25

Development of a Mobile Reactor for Large Scale Water Treatment

Berggren, Alexander January 2019 (has links)
Water pollution is one of many environmental problems that currently exists and inadequate treatment of industrial wastewater is contributing to further pollution. SpinChem AB's Rotating Bed Reactor (RBR) technology offers the possibility of water treatment by carrying out reactions between a solution and a solid phase. To move further in the field of large scale water treatment, SpinChem AB developed a prototype of a mobile reactor, i.e. a raft, carrying the RBR technology. The prototype proved that a mobile reactor can greatly reduce the process time for larger water volumes compared to a stationary RBR. The aim of this thesis is to develop the next version of the mobile reactor, with increased operational stability and autonomous driving (autopilot) as main goals. This work covers all parts in the development of the new mobile reactor which involves design, simulation, construction, electronics, software implementations and testing. The presented mobile reactor is a twin hull surface vehicle with the possibility of using two RBRs for water treatment. The steering is based on differential motor thrust and the autonomous driving was achieved using sensor data from a GPS, magnetometer and accelerometer, together with a proportional-integral-derivative (PID) type control system. The autopilot was put to the test on two different travel routes with a P and PI controller. The mobile reactor successfully followed the given routes, thus verifying that the developed mobile reactor can be used for future autonomous large scale water treatment.
26

Autopilot And Guidance Design For A Mini Rov (remotely Operated Underwater Vehicle)

Cevher, Firat Yilmaz 01 September 2012 (has links) (PDF)
This thesis consists of a mathematical model, autopilot and guidance design of a mini ROV (Remotely Operated Underwater Vehicle) and investigates the effects of environmental forces (ocean currents etc.) on the guidance algorithms. First of all, a non-linear 6 degrees-of-freedom (DOF) mathematical model is obtained. This model includes hydrodynamics forces and moments. There is no exact calculation method for hydrodynamic coefficients / however strip theory and results of computational fluid dynamics (CFD) analysis are used to calculate their approximate values. Linear mathematical model is obtained by linearization at trim points and it is used when designing surge speed, heading and depth controller. Guidance is examined by two methods such as way point guidance by line-of-sight (LOS) and way point guidance based on optimal control. Moreover, an online obstacle avoidance algorithm is developed. This thesis ends with the subject of navigation of the vehicle under GPS-like measurements and magnetic sensors measurements.
27

Towards High Speed Aerial Tracking of Agile Targets

Rizwan, Yassir January 2011 (has links)
In order to provide a novel perspective for videography of high speed sporting events, a highly capable trajectory tracking control methodology is developed for a custom designed Kadet Senior Unmanned Aerial Vehicle (UAV). The accompanying high fidelity system identification ensures that accurate flight models are used to design the control laws. A parallel vision based target tracking technique is also demonstrated and implemented on a Graphical Processing Unit (GPU), to assist in real-time tracking of the target. Nonlinear control techniques like feedback linearization require a detailed and accurate system model. This thesis discusses techniques used for estimating these models using data collected during planned test flights. A class of methods known as the Output Error Methods are discussed with extensions for dealing with wind turbulence. Implementation of these methods, including data acquisition details, on the Kadet Senior are also discussed. Results for this UAV are provided. For comparison, additional results using data from a BAC-221 simulation are also provided as well as typical results from the work done at the Dryden Flight Research Center. The proposed controller combines feedback linearization with linear tracking control using the internal model approach, and relies on a trajectory generating exosystem. Three different aircraft models are presented each with increasing levels of complexity, in an effort to identify the simplest controller that yields acceptable performance. The dynamic inversion and linear tracking control laws are derived for each model, and simulation results are presented for tracking of elliptical and periodic trajectories on the Kadet Senior.
28

Design Of An Autonomous Landing Control Algorithm For A Fixed Wing Uav

Kargin, Volkan 01 October 2007 (has links) (PDF)
This thesis concerns with the design and development of automatic flight controller strategies for the autonomous landing of fixed wing unmanned aircraft subject to severe environmental conditions. The Tactical Unmanned Aerial Vehicle (TUAV) designed at the Middle East Technical University (METU) is used as the subject platform. In the first part of this thesis, a dynamic model of the TUAV is developed in FORTRAN environment. The dynamic model is used to establish the stability characteristics of the TUAV. The simulation model also incorporates ground reaction and atmospheric models. Based on this model, the landing trajectory that provides shortest landing distance and smallest approach time is determined. Then, an automatic flight control system is designed for the autonomous landing of the TUAV. The controller uses a model inversion approach based on the dynamic model characteristics. Feed forward and mixing terms are added to increase performance of the autopilot. Landing strategies are developed under adverse atmospheric conditions and performance of three different classical controllers are compared. Finally, simulation results are presented to demonstrate the effectiveness of the design. Simulation cases include landing under crosswind, head wind, tail wind, wind shear and turbulence.
29

Autopilot And Guidance For Anti-tank Imaging Infrared Guided Missiles

Ozcan, Ali Erdem 01 October 2008 (has links) (PDF)
An anti-tank guided missile is a weapon system primarily designed to hit and destroy armored tanks and other armored vehicles. Developed first-generation command-guided and second-generation semi-automatic command guided missiles had many disadvantages and lower hit rates. For that reason, third generation imaging infrared fire-and-forget missile concept is very popular nowadays. In this thesis, mainly, a mathematical model for a fire-and-forget anti-tank missile is developed and a flight control autopilot design is presented using PID and LQR techniques. For target tracking purposes, &ldquo / correlation&rdquo / , &ldquo / centroid&rdquo / and &ldquo / active contour&rdquo / algorithms are studied and these algorithms are tested over some scenarios for maximizing hit rate. Different target scenarios and countermeasures are discussed in an artificially created virtual environment.
30

Robust Controller Design For A Fixed Wing Uav

Prach, Anna 01 September 2009 (has links) (PDF)
This study describes the design and implementation of the pitch and roll autopilots for a fixed wing unmanned vehicle. A Tactical Unmanned Aerial Vehicle (TUAV), which is designed at the Middle East Technical University (METU), is used as a platform. This work combines development of the classical and robust controllers, which are used for the pitch and roll autopilots. One of the important steps in the thesis is development of the non-linear dynamic model of the UAV, which is developed in MATLAB/Simulink environment. Two different strategies of the controller design imply development of the PID and controllers. Simulation results illustrate the performances of the designed controllers. Simulation is performed for the nominal model of the UAV and for the model that includes uncertainties and sensor noises.

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