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Development Of The West Virginia University Small Microgravity Research Facility (Wvu Smirf), Kyle G. Phillips
Development Of The West Virginia University Small Microgravity Research Facility (Wvu Smirf), Kyle G. Phillips
Graduate Theses, Dissertations, and Problem Reports
West Virginia University (WVU) has created the Small Microgravity Research Facility (SMiRF) drop tower through a WVU Research Corporation Program to Stimulate Competitive Research (PSCoR) grant on its campus to increase direct access to inexpensive and repeatable reduced gravity research. In short, a drop tower is a tall structure from which experimental payloads are dropped, in a controlled environment, and experience reduced gravity or microgravity (i.e. "weightlessness") during free fall. Currently, there are several methods for conducting scientific research in microgravity including drop towers, parabolic flights, sounding rockets, suborbital flights, NanoSats, CubeSats, full-sized satellites, manned orbital flight, and the International …
Aircraft Abnormal Conditions Detection, Identification, And Evaluation Using Innate And Adaptive Immune Systems Interaction, Dia Al Azzawi
Aircraft Abnormal Conditions Detection, Identification, And Evaluation Using Innate And Adaptive Immune Systems Interaction, Dia Al Azzawi
Graduate Theses, Dissertations, and Problem Reports
Abnormal flight conditions play a major role in aircraft accidents frequently causing loss of control. To ensure aircraft operation safety in all situations, intelligent system monitoring and adaptation must rely on accurately detecting the presence of abnormal conditions as soon as they take place, identifying their root cause(s), estimating their nature and severity, and predicting their impact on the flight envelope.;Due to the complexity and multidimensionality of the aircraft system under abnormal conditions, these requirements are extremely difficult to satisfy using existing analytical and/or statistical approaches. Moreover, current methodologies have addressed only isolated classes of abnormal conditions and a reduced …
Numerical Investigation Of The Influence Of Elevated Turbulence Levels On The Cooling Effectiveness Of An Anti-Vortex Hole Geometry, Timothy William Repko
Numerical Investigation Of The Influence Of Elevated Turbulence Levels On The Cooling Effectiveness Of An Anti-Vortex Hole Geometry, Timothy William Repko
Graduate Theses, Dissertations, and Problem Reports
A novel film cooling hole geometry for use in gas turbine engines has been investigated numerically by solving the Reynolds Averaged Navier-Stokes equations in a commercial CFD code (STAR-CCM+) with varying turbulence intensity and length scale using the k-o SST turbulence model. Both steady and unsteady results were considered in order to investigate the effects of freestream turbulence intensity and length scale on this novel anti-vortex hole (AVH) concept. The AVH geometry utilizes two side holes, one on each side of the main hole, to attempt to mitigate the vorticity from the jet from the main hole. The AVH concept …
A Force Sensor Array For Space Applications, Timothy L. Weadon
A Force Sensor Array For Space Applications, Timothy L. Weadon
Graduate Theses, Dissertations, and Problem Reports
The need for force feedback and spatial awareness of contact in harsh environment applications, such as space servicing, has been unsatisfied due to the inability of current sensor technology to resist environmental effects. In this work, capacitive sensors based on a porous polymer-ceramic composite structure were evaluated for potential use in future operations within robotic end-effectors, withstanding temperatures ranging from -80 °C to 120 °C and forces up to 350 kPa. A thin-film design is utilized to allow for ease of embedding, allowing sensors to be implemented into exciting robotic hardware with minimal intrusion, and protecting sensors from electron bombardment, …
Folding Solid-Membrane Wing Structure For A Micro Air Vehicle, Joe D. Allen Jr.
Folding Solid-Membrane Wing Structure For A Micro Air Vehicle, Joe D. Allen Jr.
Graduate Theses, Dissertations, and Problem Reports
The design of a solid-membrane folding wing for use on a tube launched micro air vehicle (MAV), and experimental wind tunnel results of the wing integrated on an engineering MAV model are presented herein. Due to the sizing and performance requirements of the MAV, the wing must provide sufficient wing area while minimizing its stowed footprint. Many current available methods for folding the wing for such a MAV sacrifice aerodynamic efficiency or are cost prohibitive. The solid-membrane wing design presented blends elements of a solid semi-rigid wing with those of a membrane wing. This provides the aerodynamic efficiency of a …
Aerodynamic Parameter Identification Of A Venus Lander, Robert A. Sykes
Aerodynamic Parameter Identification Of A Venus Lander, Robert A. Sykes
Graduate Theses, Dissertations, and Problem Reports
An analysis was conducted to identify the parameters of an aerodynamic model for a Venus lander based on experimental free-flight data. The experimental free-flight data were collected in the NASA Langley 20-ft Vertical Spin Tunnel with a 25-percent Froude-scaled model. The experimental data were classified based on the wind tunnel run type: runs where the lander model was unperturbed over the course of the run, and runs were the model was perturbed (principally in pitch, yaw, and roll) by the wind tunnel operator. The perturbations allow for data to be obtained at higher wind angles and rotation rates than those …
Numerical And Experimental Study On The Ability Of Dynamic Roughness To Alter The Development Of A Leading Edge Vortex, Christopher D. Griffin
Numerical And Experimental Study On The Ability Of Dynamic Roughness To Alter The Development Of A Leading Edge Vortex, Christopher D. Griffin
Graduate Theses, Dissertations, and Problem Reports
Dynamic stall is an unsteady aerodynamic phenomenon garnering much research interest because it occurs in a variety of applications. For example, dynamic stall is known to occur on helicopter rotor blades, wind turbines, high maneuvering military aircraft, and flapping wings. Dynamic stall occurs when an aerodynamic lifting device, such as an airfoil, wing, or turbomachine blade, undergoes a rapid pitching motion. It also occurs on lifting devices that are impulsively started at high angles of attack. Dynamic stall can "delay" aerodynamic stall to angles of attack that are significantly beyond the static stall angle of attack.;During dynamic stall a large …
Machine-Vision-Based Pose Estimation System Using Sensor Fusion For Autonomous Satellite Grappling, Andres Felipe Velasquez Escandon
Machine-Vision-Based Pose Estimation System Using Sensor Fusion For Autonomous Satellite Grappling, Andres Felipe Velasquez Escandon
Graduate Theses, Dissertations, and Problem Reports
When capturing a non-cooperative satellite during an on-orbit satellite servicing mission, the position and orientation (pose) of the satellite with respect to the servicing vessel is required in order to guide the robotic arm of the vessel towards the satellite. The main objective of this research is the development of a machine vision-based pose estimation system for capturing a non-cooperative satellite. The proposed system finds the satellite pose using three types of natural geometric features: circles, lines and points, and it merges data from two monocular cameras and three different algorithms (one for each type of geometric feature) to increase …
Wind And Wake Sensing With Uav Formation Flight: System Development And Flight Testing, Trenton Jameson Larrabee
Wind And Wake Sensing With Uav Formation Flight: System Development And Flight Testing, Trenton Jameson Larrabee
Graduate Theses, Dissertations, and Problem Reports
Wind turbulence including atmospheric turbulence and wake turbulence have been widely investigated; however, only recently it become possible to use Unmanned Aerial Vehicles (UAVs) as a validation tool for research in this area. Wind can be a major contributing factor of adverse weather for aircraft. More importantly, it is an even greater risk towards UAVs because of their small size and weight. Being able to estimate wind fields and gusts can potentially provide substantial benefits for both unmanned and manned aviation. Possible applications include gust suppression for improving handling qualities, a better warning system for high wind encounters, and enhanced …
Droplet Impact Sub-Cavity Histories And Pdpa Spray Experiments For Spray Cooling Modeling, Nicholas Lee Hillen
Droplet Impact Sub-Cavity Histories And Pdpa Spray Experiments For Spray Cooling Modeling, Nicholas Lee Hillen
Graduate Theses, Dissertations, and Problem Reports
Spray cooling is a topic of current interest for its ability to uniformly remove high levels of waste heat from densely packed microelectronics. It has demonstrated the ability to achieve very high heat fluxes, up to 500 W/cm2 with water as the coolant, making it an attractive active thermal management tool.;Full Computational Fluid Dynamic (CFD) simulations of spray cooling are infeasible due to the complexity of the spray (drops fluxes of 106 drops/cm2-sec) and heater surface physics requiring impractical resources. Thus a Monte-Carlo (MC) spray cooling simulation model based on empirical data is under development to serve as a cost …
Sensitivity And Stability Analysis Of Nonlinear Kalman Filters With Application To Aircraft Attitude Estimation, Matthew Brandon Rhudy
Sensitivity And Stability Analysis Of Nonlinear Kalman Filters With Application To Aircraft Attitude Estimation, Matthew Brandon Rhudy
Graduate Theses, Dissertations, and Problem Reports
No abstract provided.
Development Of An Integrated Intelligent Multi -Objective Framework For Uav Trajectory Generation, Jennifer Nicole Wilburn
Development Of An Integrated Intelligent Multi -Objective Framework For Uav Trajectory Generation, Jennifer Nicole Wilburn
Graduate Theses, Dissertations, and Problem Reports
This thesis explores a variety of path planning and trajectory generation schemes intended for small, fixed-wing Unmanned Aerial Vehicles. Throughout this analysis, discrete and pose-based methods are investigated. Pose-based methods are the focus of this research due to their increased flexibility and typically lower computational overhead.;Path planning in 3 dimensions is also performed. The 3D Dubins methodology presented is an extension of a previously suggested approach and addresses both the mathematical formulation of the methodology, as well as an assessment of numerical issues encountered and the solutions implemented for these.;The main contribution of this thesis is a 3-dimensional clothoid trajectory …
Tuning The Electrical And Thermal Conductivities Of Thermoelectric Oxides Through Impurity Doping, Maria A. Torres Arango
Tuning The Electrical And Thermal Conductivities Of Thermoelectric Oxides Through Impurity Doping, Maria A. Torres Arango
Graduate Theses, Dissertations, and Problem Reports
Waste heat and thermal gradients available at power plants can be harvested to power wireless networks and sensors by using thermoelectric (TE) generators that directly transform temperature differentials into electrical power. Oxide materials are promising for TE applications in harsh industrial environments for waste heat recovery at high temperatures in air, because they are lightweight, cheaply produced, highly efficient, and stable at high temperatures in air. Ca3Co4O9(CCO) with layered structure is a promising p-type thermoelectric oxide with extrapolated ZT value of 0.87 in single crystal form [1]. However the ZT values for the polycrystalline ceramics remain low of ∼0.1-0.3. In …
Analysis Of Gps Abnormal Conditions Within Fault Tolerant Control Laws, Gahssan Al-Sinbol
Analysis Of Gps Abnormal Conditions Within Fault Tolerant Control Laws, Gahssan Al-Sinbol
Graduate Theses, Dissertations, and Problem Reports
The Global Position System (GPS) is a critical element for the functionality of autonomous flying vehicles. The GPS operation at normal and abnormal conditions directly impacts the trajectory tracking performance of the autonomous Unmanned Aerial Vehicles (UAVs) controllers. The effects of GPS parameter variation must be well understood and user-friendly computational tools must be developed to facilitate the design and evaluation of fault tolerant control laws.;This thesis presents the development of a simplified GPS error model in Matlab/Simulink and its use performing a sensitivity analysis of GPS parameters effect under system normal and abnormal operation on different UAV trajectory tracking …
Hybrid Projectile Body Angle Estimation For Selectable Range Increase, Christopher J. Gioia
Hybrid Projectile Body Angle Estimation For Selectable Range Increase, Christopher J. Gioia
Graduate Theses, Dissertations, and Problem Reports
A Hybrid Projectile (HP) is a tube launched munition that transforms into a gliding UAV, and is currently being researched at West Virginia University. A simple launch timer was first envisioned to control the transformation point in order to achieve maximum distance. However, this timer would need to be reprogrammed for any distance less than maximum range due to the nominal time to deployment varying with launch angle. A method was sought for automatic wing deployment that would not require reprogramming the round. A body angle estimation system was used to estimate the pitch of the HP relative to the …
Aerodynamics Investigation Of Faceted Airfoils At Low Reynolds Number, Zachary G. Napolillo
Aerodynamics Investigation Of Faceted Airfoils At Low Reynolds Number, Zachary G. Napolillo
Graduate Theses, Dissertations, and Problem Reports
The desire and demand to fly farther and faster has progressively integrated the concept of optimization with airfoil design, resulting in increasingly complex numerical tools pursuing efficiency often at diminishing returns; while the costs and difficulty associated with fabrication increases with design complexity. Such efficiencies may often be necessary due to the power density limitations of certain aircraft such as small unmanned aerial vehicles (UAVs) and micro air vehicles (MAVs).;This research, however, focuses on reducing the complexity of airfoils for applications where aerodynamic performance is less important than the efficiency of manufacturing; in this case a Hybrid Projectile. By employing …
Novel Engineered Nanostructured Complex Oxide For High Temperature Thermoelectric Power Generation, Diego F. Palacio
Novel Engineered Nanostructured Complex Oxide For High Temperature Thermoelectric Power Generation, Diego F. Palacio
Graduate Theses, Dissertations, and Problem Reports
Thermoelectric power generators are a promising technology that can produce electrical power directly from waste heat emitted in energy production and consumption systems. The essential component of thermoelectric generators is the thermoelectric material which performs the energy conversion process. In order to make thermoelectric devices to be considered a significant contributor to US energy infrastructure, it is essential first to foster improvements in high performance thermoelectric materials. They must possess not only a high conversion efficiency, but also need be composed of nontoxic and abundantly available elemental materials having high chemical stability in air up to 800-1000 K. In comparison …
Onboard Parameter Identification For A Small Uav, Amanda K. Mcgrail
Onboard Parameter Identification For A Small Uav, Amanda K. Mcgrail
Graduate Theses, Dissertations, and Problem Reports
One of the main research focus areas of the WVU Flight Control Systems Laboratory (FCSL) is the increase of flight safety through the implementation of fault tolerant control laws. For some fault tolerant flight control approaches with adaptive control laws, the availability of accurate post failure aircraft models improves performance. While look-up tables of aircraft models can be created for failure conditions, they may fail to account for all possible failure scenarios. Thus, a real-time parameter identification program eliminates the need to have predefined models for all potential failure scenarios. The goal of this research was to identify the dimensional …
Augmented Propeller Design With The Use Of A Passive Circulation Control Pressurization System, Jonathan Kweder
Augmented Propeller Design With The Use Of A Passive Circulation Control Pressurization System, Jonathan Kweder
Graduate Theses, Dissertations, and Problem Reports
Circulation control is a high-lift device used on the main wing of an aircraft. This technology has been in the research and development phase for over sixty years primarily for fixed-wing aircraft when the early models were referred to as "blown flaps." Circulation control works by increasing the near surface velocity of the airflow over the leading edge and/or trailing edge of a specially designed aircraft wing using a series of blowing slots that eject high velocity jets of air. The wing has a rounded trailing edge, and ejects the air tangentially, through these slots inducing the Coanda Effect. This …
Effect Of Seat Orientation On Ingress/Egress Joint Kinematics And Reach Envelope, Christopher W. Moore
Effect Of Seat Orientation On Ingress/Egress Joint Kinematics And Reach Envelope, Christopher W. Moore
Graduate Theses, Dissertations, and Problem Reports
Crew modules use recumbent seats to sustain increased acceleration in the upright direction. Entry (ingress) and exit (egress) of such seats require different techniques. Most of the existing research on ingress and egress biomechanics was done using vertically mounted automobile seats. In this study, ingress and egress and planar reach motions performed using seats mounted in vertical and horizontal orientations were evaluated. An eight camera (MX-13 series) optical motion analysis system (Vicon, Nexus, UK) was used to record the 3D kinematic data. Ten healthy male participants performed ingress and egress motions using the following three seat orientations, while reach tasks …
Comparison Of Three Machine Vision Pose Estimation Systems Based On Corner, Line, And Ellipse Extraction For Satellite Grasping, Jeremy A. Luckett
Comparison Of Three Machine Vision Pose Estimation Systems Based On Corner, Line, And Ellipse Extraction For Satellite Grasping, Jeremy A. Luckett
Graduate Theses, Dissertations, and Problem Reports
The primary objective of this research was to use three different types of features (corners, lines, and ellipses) for the purpose of satellite grasping with a machine vision-based pose estimation system. The corner system is used to track sharp corners or small features (holes or bolt) in the satellite; the lines system tracks sharp edges while the ellipse system tracks circular features in the satellite. The corner and line system provided 6 degrees of freedom (DOF) pose (rotation matrix and translation vector) of the satellite with respect to the camera frame, while the ellipse system provided 5 DOF pose (normal …
Uav Simulation Environment For Autonomous Flight Control Algorithms, Ondrej Karas
Uav Simulation Environment For Autonomous Flight Control Algorithms, Ondrej Karas
Graduate Theses, Dissertations, and Problem Reports
This thesis presents the development of a UAV simulation environment for the design, analysis, and comparison of autonomous flight control laws. The simulation environment was developed in MATLAB/Simulink, with custom map generation software and FlightGear 3-D visualization. Graphical user interface of the simulation environment is user-friendly and all available options are discussed in detail. Aircraft dynamic models are presented, with emphasis on newly designed UAV models. Five different aircraft models are available, with several path planning and trajectory tracking algorithms implemented. Emphasis is given to simulation of failures and other abnormal conditions, so that appropriate tools for failure detection, evaluation, …
Experimental Investigation Of Particulate Deposition On A Simulated Film-Cooled Turbine Vane Pressure Surface In A High Pressure Combustion Facility, Robert G. Murphy
Experimental Investigation Of Particulate Deposition On A Simulated Film-Cooled Turbine Vane Pressure Surface In A High Pressure Combustion Facility, Robert G. Murphy
Graduate Theses, Dissertations, and Problem Reports
Use of coal syngas for Integrated Gasification Combined Cycle (IGCC) industrial gas turbines introduces contaminants into the flow that can deposit onto the components of the first stage of the turbine. These deposit structures may create alterations in the cooling scheme and can erode or react with thermal barrier coatings (TBC). A study was performed to examine the evolution and contributing factors to the growth of deposit structures in a simulated gas turbine environment. Tests were performed in the high pressure/temperature aerothermal facility at the Department of Energy's (DoE) National Energy Technology Laboratory (NETL) in Morgantown, WV. The facility was …
A Simplified Icing Model For Simulation And Analysis Of Dynamic Effects, Matthew A. Cunningham
A Simplified Icing Model For Simulation And Analysis Of Dynamic Effects, Matthew A. Cunningham
Graduate Theses, Dissertations, and Problem Reports
Ice accretions on aerodynamic surfaces are a major concern during flight. In this research effort, glaze ice is being modeled and its effects on aircraft dynamics analyzed. This type of ice builds up as a clear layer on aerodynamic surfaces and other components such as antennas and intakes. Glaze icing is dangerous because as the amount of ice increases, it alters the shape and properties of the aerodynamic surface. Wind tunnel tests of this type of icing and data analysis have shown that the main effects of icing consist of decrease of lift coefficient, reduction of stall angle of attack, …
Initiation And Evolution Of Matrix Cracking In Non-Symmetric Laminates Under In-Plane And Flexural Loading, Adi Adumitroaie
Initiation And Evolution Of Matrix Cracking In Non-Symmetric Laminates Under In-Plane And Flexural Loading, Adi Adumitroaie
Graduate Theses, Dissertations, and Problem Reports
A constitutive model of progressive matrix cracking in fibers reinforced laminated composite is developed for the case of both membrane and flexural deformation. The progressive damage model makes use of the following key ingredients i) an appropriate material model for calculating the reduced thermo--elastic properties of the laminate containing individual plies affected by matrix cracking, ii) an energy based damage evolution criterion inspired by Fracture Mechanics, iii) an homogenization technique inspired by Continuum Damage Mechanics, iv) an iterative procedure in order to detect the conditions for damage growth in individual plies of the laminate, and to increase the damage level …
Planform Characterization Of A High Lift, Low Speed, Ground Effect Glider, Meagan L. Hubbell
Planform Characterization Of A High Lift, Low Speed, Ground Effect Glider, Meagan L. Hubbell
Graduate Theses, Dissertations, and Problem Reports
The main objective of this research was to design and develop a planform shape for a single passenger, unpowered, subsonic glider that relies on gravitational forces for momentum. The wing structure and aerodynamic shape optimized the benefits of near-ground flight (i.e. the increased lift and decreased induced drag), and as a result reduced the overall aircraft weight and wingspan, and enhanced the maneuverability of the craft.;The design faced many challenges as a result of flight in the ground effect regime. There were natural instabilities, primarily in the longitudinal direction that caused the glider to pitch up. In addition, the wing …
Numerical Flight Testing Of A Tube-Launched Transformable Micro Air Vehicle, William L. Vogel
Numerical Flight Testing Of A Tube-Launched Transformable Micro Air Vehicle, William L. Vogel
Graduate Theses, Dissertations, and Problem Reports
The micro air vehicle (MAV) is a relatively new class of Unmanned Aerial Vehicles (UAVs) and has drawn much interest in recent years within the aerospace industry, especially for military surveillance applications. The aerodynamic characteristics of existing MAV designs have been documented in aeronautics literature; however, the MAV presented in this research had unusual design specifications in which the overall mass and cruise speed were greater in comparison to the existing designs. Additionally, the MAV was designed to transform from ballistic flight to aircraft flight for the purpose of gaining performance improvements in both range and accuracy. This new MAV …
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 …
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. …