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Utilization Of Igs Information For Improved Real-Time Gps Positioning, Francis James Barchesky
Utilization Of Igs Information For Improved Real-Time Gps Positioning, Francis James Barchesky
Graduate Theses, Dissertations, and Problem Reports
The estimation of a precise user's position is a difficult and complex problem. In addition, the use of geodetic grade position instruments is often not possible for Small Unmanned Aerial Vehicle (SUAV) systems. However, the availability of the global navigation satellite system (GNSS) and International GNSS Service (IGS) predicted product data allows an attempt to increase the precision of a navigation algorithm, which is the aim in this thesis.;The utilization of this information within an algorithm work environment is a complex problem, requiring the development of multiple tools in order to use and access the IGS raw and product data. …
Modeling And Analysis Of Multiple Engine Aircraft Configurations For Fault Tolerant Control, Frederick M. Beamer
Modeling And Analysis Of Multiple Engine Aircraft Configurations For Fault Tolerant Control, Frederick M. Beamer
Graduate Theses, Dissertations, and Problem Reports
A formal framework is presented that allows for the analysis of the potential for using engine thrust control for aircraft actuator failure accommodation. Three sets of parameters have been identified as critical: number of engines and their position, engine thrust and throttle dynamics, and type and severity of the actuator failure. A mathematical model was developed that allows for the determination of the values of some of the parameters when the others are imposed such as determining the thrust control authority when the engine locations and Euler angles are known. Additionally, the engine locations can be determined when the thrust …
Modeling And Flight Testing Of Differential Thrust And Thrust Vectoring On A Small Uav, Zachary J. Merceruio
Modeling And Flight Testing Of Differential Thrust And Thrust Vectoring On A Small Uav, Zachary J. Merceruio
Graduate Theses, Dissertations, and Problem Reports
The primary objectives of this research are to mathematically model the propulsion forces applied to the aircraft during nominal, differential thrust, and thrust vectored flight configurations, and verify this modeling through simulation and flight testing experiments. This thesis outlines the modeling process, simulator development, design, and implementation of a propulsion assisted control system for the WVU Flight Control Systems Lab (FCSL) research aircraft. Differential thrust and thrust vectoring introduce additional propulsive terms in the aircraft force equations that are not present when the thrust line passes through the center of gravity. These additional forces were modeled and incorporated into a …
Sensor Fusion Based Fault-Tolerant Attitude Estimation Solutions For Small Unmanned Aerial Vehicles, Jason Nicholas Gross
Sensor Fusion Based Fault-Tolerant Attitude Estimation Solutions For Small Unmanned Aerial Vehicles, Jason Nicholas Gross
Graduate Theses, Dissertations, and Problem Reports
Navigation-grade inertial sensors are often too expensive and too heavy for use in most Small Unmanned Aerial Vehicle (SUAV) systems. Low-cost Micro-Electrical-Mechanical-Systems (MEMS) inertial sensors provide an attractive alternative, but currently do not provide an adequate navigation solution alone due to the presence of sensor bias. Toward addressing this problem, this research focuses on the development and experimental evaluation of sensor fusion algorithms to combine partially redundant information from low-cost sensor to achieve accurate SUAV attitude estimation. To conduct this research, several sets of SUAVs flight data that include measurements from a low-cost MEMS based Inertial Measurement Unit, a Global …
Aircraft Parameter Identification For Application Within A Fault-Tolerant Flight Control System, Kerri B. Phillips
Aircraft Parameter Identification For Application Within A Fault-Tolerant Flight Control System, Kerri B. Phillips
Graduate Theses, Dissertations, and Problem Reports
A parameter identification study was conducted to identify a detailed aircraft mathematical model for application within a fault-tolerant flight control system that aims to detect, identify, and accommodate for sensor and actuator failures. Specifically, a mathematical model was identified under nominal conditions for two aircraft platforms, and a model was developed for one platform under actuator failure conditions. These models are to be used in flight control law design and to account for actuator failures on the primary control surfaces for one of the research platforms. In order to accurately model the aircraft behavior following a control surface failure, the …
Parameter Estimation Analysis For Hybrid Adaptive Fault Tolerant Control, Peter B. Eshak
Parameter Estimation Analysis For Hybrid Adaptive Fault Tolerant Control, Peter B. Eshak
Graduate Theses, Dissertations, and Problem Reports
Research efforts have increased in recent years toward the development of intelligent fault tolerant control laws, which are capable of helping the pilot to safely maintain aircraft control at post failure conditions. Researchers at West Virginia University (WVU) have been actively involved in the development of fault tolerant adaptive control laws in all three major categories: direct, indirect, and hybrid. The first implemented design to provide adaptation was a direct adaptive controller, which used artificial neural networks to generate augmentation commands in order to reduce the modeling error. Indirect adaptive laws were implemented in another controller, which utilized online PID …
Implementation Of A Helicopter Flight Simulator With Individual Blade Control, Andrew G. Zinchiak
Implementation Of A Helicopter Flight Simulator With Individual Blade Control, Andrew G. Zinchiak
Graduate Theses, Dissertations, and Problem Reports
Nearly all modern helicopters are designed with a swashplate-based system for control of the main rotor blades. However, the swashplate-based approach does not provide the level of redundancy necessary to cope with abnormal actuator conditions. For example, if an actuator fails (becomes locked) on the main rotor, the cyclic inputs are consequently fixed and the helicopter may become stuck in a flight maneuver. This can obviously be seen as a catastrophic failure, and would likely lead to a crash.;These types of failures can be overcome with the application of individual blade control (IBC). IBC is achieved using the blade pitch …
Design Of Fault Tolerant Control System For Individual Blade Control Helicopters, Sergio Tamayo
Design Of Fault Tolerant Control System For Individual Blade Control Helicopters, Sergio Tamayo
Graduate Theses, Dissertations, and Problem Reports
This dissertation presents the development of a fault tolerant control scheme for helicopters fitted with individually controlled blades. This novel approach attempts to improve fault tolerant capabilities of helicopter control system by increasing control redundancy using additional actuators for individual blade input and software re-mixing to obtain nominal or close to nominal conditions under failure. An advanced interactive simulation environment has been developed including modeling of sensor failure, swashplate actuator failure, individual blade actuator failure, and blade delamination to support the design, testing, and evaluation of the control laws. This simulation environment is based on the blade element theory for …