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Design And Analysis Of Compressed Air Power Harvesting Systems, Zachary James Sadler Dec 2017

Design And Analysis Of Compressed Air Power Harvesting Systems, Zachary James Sadler

Theses and Dissertations

Procedure for site discovery, system design, and optimization of power harvesting systems is developed with an emphasis on application to air compressors. Limitations for the usage of infrared pyrometers is evaluated. A system of governing equations for thermoelectric generators is developed. A solution method for solving the system of equations is created in order to predict power output from the device. Payback analysis is proposed for determining economic viability. A genetic algorithm is used to optimize the power harvesting system payback with changing quantities and varieties of thermoelectric generators, as well as the back work put into cooling the thermoelectric …


Eigenblades: Application Of Computer Vision And Machine Learning For Mode Shape Identification, Alex W. La Dec 2017

Eigenblades: Application Of Computer Vision And Machine Learning For Mode Shape Identification, Alex W. La

Theses and Dissertations

On August 27, 2016, Southwest Airlines flight 3472 from New Orleans to Orlando had to perform an emergency landing when a fan blade separated from the engine hub and destroyed the cowling and punctured the fuselage. Initial findings from the metallurgical examination conducted in the National Transpiration Safety Board Materials Laboratory found that the fracture surface of the missing blade showed curving crack arrest lines consistent with fatigue crack growth. Fatigue is often cause by resonate vibrations. Modal analysis is a method that can model the natural frequencies and bending modes of turbomachinery blades. When performing modal analysis with finite …


Eigenblades: Application Of Computer Vision And Machine Learning For Mode Shape Identification, Alex W. La Dec 2017

Eigenblades: Application Of Computer Vision And Machine Learning For Mode Shape Identification, Alex W. La

Theses and Dissertations

On August 27, 2016, Southwest Airlines flight 3472 from New Orleans to Orlando had to perform an emergency landing when a fan blade separated from the engine hub and destroyed the cowling and punctured the fuselage. Initial findings from the metallurgical examination conducted in the National Transpiration Safety Board Materials Laboratory found that the fracture surface of the missing blade showed curving crack arrest lines consistent with fatigue crack growth. Fatigue is often cause by resonate vibrations. Modal analysis is a method that can model the natural frequencies and bending modes of turbomachinery blades. When performing modal analysis with finite …


Design And Analysis Of Compressed Air Power Harvesting Systems, Zachary James Sadler Dec 2017

Design And Analysis Of Compressed Air Power Harvesting Systems, Zachary James Sadler

Theses and Dissertations

Procedure for site discovery, system design, and optimization of power harvesting systems is developed with an emphasis on application to air compressors. Limitations for the usage of infrared pyrometers is evaluated. A system of governing equations for thermoelectric generators is developed. A solution method for solving the system of equations is created in order to predict power output from the device. Payback analysis is proposed for determining economic viability. A genetic algorithm is used to optimize the power harvesting system payback with changing quantities and varieties of thermoelectric generators, as well as the back work put into cooling the thermoelectric …


A Comparison Between Self-Cleaning Properties Via Rolling Droplets And Condensation On Superhyrophobic Surfaces, David Leland Miller Dec 2017

A Comparison Between Self-Cleaning Properties Via Rolling Droplets And Condensation On Superhyrophobic Surfaces, David Leland Miller

Theses and Dissertations

Superhydrophobic (SH) surfaces are super water repellent surfaces on which a droplet of water will bead up like a marble and roll off the surface with minimal tilting of the surface. This is caused by the combination of a hydrophobic coating and a rough surface structure. To achieve thermodynamic stability, surface tension of the water pulls the droplet into this shape to minimize the contact area between the droplet and the surface. This creates a high contact angle (CA) between the droplet and the surface and a low sliding angle (SA) of which the droplet begins to roll off the …


An Obstacle Avoidance System For The Visually Impaired Using 3-D Point Cloud Processing, Evan Justin Taylor Dec 2017

An Obstacle Avoidance System For The Visually Impaired Using 3-D Point Cloud Processing, Evan Justin Taylor

Theses and Dissertations

The long white cane offers many benefits for the blind and visually impaired. Still, many report being injured both indoors and outdoors while using the long white cane. One frequent cause of injury is due to the fact that the long white cane cannot detect obstacles above the waist of the user. This thesis presents a system that attempts to augment the capabilities of the long white cane by sensing the environment around the user, creating a map of obstacles within the environment, and providing simple haptic feedback to the user. The proposed augmented cane system uses the Asus Xtion …


Microstructural Evaluation Of Hydrogen Embrittlement And Successive Recovery In Advanced High Strength Steel, Quentin Scott Allen Dec 2017

Microstructural Evaluation Of Hydrogen Embrittlement And Successive Recovery In Advanced High Strength Steel, Quentin Scott Allen

Theses and Dissertations

Advanced high strength steels (AHSS) have high susceptibility to hydrogen embrittlement, and are often exposed to hydrogen environments in processing. In order to study the embrittlement and recovery of steel, tensile tests were conducted on two different types of AHSS over time after hydrogen charging. Concentration measurements and hydrogen microprinting were carried out at the same time steps to visualize the hydrogen behavior during recovery. The diffusible hydrogen concentration was found to decay exponentially, and equations were found for the two types of steel. Hydrogen concentration decay rates were calculated to be -0.355 /hr in TBF steel, and -0.225 /hr …


Trading Off Sound Pressure Level And Average Power Production For Wind Farm Layout Optimization, Eric Tingey, Andrew Ning Dec 2017

Trading Off Sound Pressure Level And Average Power Production For Wind Farm Layout Optimization, Eric Tingey, Andrew Ning

Faculty Publications

This research explores the trade-offs between a wind farm’s average power production and noise impact on nearby observers. Two specific wind farm designs were studied and optimized using the FLORIS wake model and an acoustic model based on semi-empirical turbine noise calculations. It was found in the two wind farms that the average power production could be increased, up to 8.01% in one and 3.63% in the other, ignoring sound level considerations. Including a noise restriction in the optimization had a minimal impact on the optimal average power production within about a five-decibel range. Past this range, sound limitations decreased …


Characterizing The Electromechanical Response Of Flexible Foam For Multifunctional Impact-Sensing Applications, Evan Troy Bird Nov 2017

Characterizing The Electromechanical Response Of Flexible Foam For Multifunctional Impact-Sensing Applications, Evan Troy Bird

Theses and Dissertations

Flexible foams have unique properties that make them well-suited to several engineering systems. They are often used in impact-related applications because of their superior energy absorption performance. Many multifunctional materials are also derived from flexible foams due to their high customizability, which allows them to satisfy a wide range of performance requirements. Though flexible foams have high potential in these and other classes of material applications, their success relies on the proper characterization of their complex behavior. This thesis promotes the application of flexible foams by characterizing their electromechanical response through both experimental and theoretical approaches. One study in this …


Developing New Classes Of Thick-Origami-Based Mechanisms: Conceal-And-Reveal Motion And Folding Printed Circuit Boards, Bryce Parker De Figueiredo Nov 2017

Developing New Classes Of Thick-Origami-Based Mechanisms: Conceal-And-Reveal Motion And Folding Printed Circuit Boards, Bryce Parker De Figueiredo

Theses and Dissertations

Origami-adapted mechanisms form the basis of an increasing number of engineered systems. As most of these systems require the use of non-paper materials, various methods for accommodating thickness have been developed. These methods have opened new avenues for origami-based design. This work introduces approaches for the design of two new classes of thick-origami systems and demonstrates the approaches in hardware. One type of system, called "conceal-and-reveal,'' is introduced, and a method of designing these mechanisms is developed. Techniques are also developed for designing folding printed circuit boards which are fabricated from a single sheet of material. This enables areas of …


Highly Compressible Origami Bellows For Harsh Environments, Jared J. Butler Nov 2017

Highly Compressible Origami Bellows For Harsh Environments, Jared J. Butler

Theses and Dissertations

The use of origami-based bellows is of interest in fields where traditional metal bellows are incapable of meeting compression, mass, or flexibility constraints. Metal bellows are often used in space applications but frequently complicate spacecraft design. Origami-based bellows capable of meeting design constraints while adequately shielding sensitive spacecraft parts may be advantageous to space mechanism design. The design and testing of a highly compressible origami bellows for harsh environments is described. Several origami patterns were evaluated and the Kresling fold pattern was designed to meet constraints and selected for use in the bellows design. Origami bellows were prototyped in five …


Hydrodynamic And Thermal Effects Of Sub-Critical Heating On Superhydrophobic Surfaces And Microchannels, Adam M. Cowley Nov 2017

Hydrodynamic And Thermal Effects Of Sub-Critical Heating On Superhydrophobic Surfaces And Microchannels, Adam M. Cowley

Theses and Dissertations

This dissertation focuses on the effects of heating on superhydrophobic (SHPo) surfaces. The work is divided into two main categories: heat transfer without mass transfer and heat transfer in conjunction with mass transfer. Numerical methods are used to explore the prior while experimental methods are utilized for the latter. The numerical work explores convective heat transfer in SHPo parallel plate microchannels and is separated into two stand-alone chapters that have been published archivally. The first considers surfaces with a rib/cavity structure and the second considers surfaces patterned with a square lattice of square posts. Laminar, fully developed, steady flow with …


Considering Manufacturing In The Design Of Thick-Panel Origami Mechanisms, Erica Brunson Crampton Oct 2017

Considering Manufacturing In The Design Of Thick-Panel Origami Mechanisms, Erica Brunson Crampton

Theses and Dissertations

Origami has been investigated and demonstrated for engineering applications in recent years. Many techniques for accommodating the thickness of most engineering materials have been developed. In this work, tables comparing performance and manufacturing characteristics are presented. These tables can serve as useful design tools for engineers when selecting an appropriate thickness-accommodation technique for their application. The use of bent sheet metal for panels in thick-origami mechanisms shows promise as a panel design approach that mitigates several trade-offs between performance and manufacturing characteristics. A process is described and demonstrated that can be employed to use sheet metal in designs of origami-adapted …


Distribution Of Essential Tremor In The Degrees Of Freedom Of The Upper Limb, Charles Charles Pigg Sep 2017

Distribution Of Essential Tremor In The Degrees Of Freedom Of The Upper Limb, Charles Charles Pigg

Theses and Dissertations

This study seeks to understand upper limb tremor in subjects with essential tremor (ET). A thorough understanding of tremor distribution will allow for the more effective development of tremor suppression devices, which offer an alternative to current treatments. Previous studies primarily focused on tremor in the hand only. This study seeks to characterize the distribution of tremor throughout the upper limb. We measured tremor in 25 subjects diagnosed with ET using motion capture, which provided 0displacement information of the limb during multiple postural and kinetic tasks. Inverse kinematics allowed us to analyze the motion capture data in the 7 major …


Distribution Of Essential Tremor In The Degrees Of Freedom Of The Upper Limb, Adam Charles Pigg Sep 2017

Distribution Of Essential Tremor In The Degrees Of Freedom Of The Upper Limb, Adam Charles Pigg

Theses and Dissertations

This study seeks to understand upper limb tremor in subjects with essential tremor (ET). A thorough understanding of tremor distribution will allow for the more effective development of tremor suppression devices, which offer an alternative to current treatments. Previous studies primarily focused on tremor in the hand only. This study seeks to characterize the distribution of tremor throughout the upper limb.We measured tremor in 25 subjects diagnosed with ET using motion capture, which provided displacement information of the limb during multiple postural and kinetic tasks. Inverse kinematics allowed us to analyze the motion capture data in the 7 major degrees …


Deep Visual Gravity Vector Detection For Unmanned Aircraft Attitude Estimation, Gary J. Ellingson, David Wingate, Tim Mclain Sep 2017

Deep Visual Gravity Vector Detection For Unmanned Aircraft Attitude Estimation, Gary J. Ellingson, David Wingate, Tim Mclain

Faculty Publications

This paper demonstrates a feasible method for using a deep neural network as a sensor to estimate the attitude of a flying vehicle using only flight video. A dataset of still images and associated gravity vectors was collected and used to perform supervised learning. The network builds on a previously trained network and was trained to be able to approximate the attitude of the camera with an average error of about 8 degrees. Flight test video was recorded and processed with a relatively simple visual odometry method. The aircraft attitude is then estimated with the visual odometry as the state …


Improving The Floris Wind Plant Model For Compatibility With Gradient-Based Optimization, Jared Thomas, Pieter Gebraad, Andrew Ning Aug 2017

Improving The Floris Wind Plant Model For Compatibility With Gradient-Based Optimization, Jared Thomas, Pieter Gebraad, Andrew Ning

Faculty Publications

The FLOw Redirection and Induction in Steady-state (FLORIS) model, a parametric wind turbine wake model that predicts steady state wake characteristics based on wind turbine position and yaw angle, was developed for optimization of control settings and turbine locations. This paper provides details on the recent changes made to the FLORIS model to make the model more suitable for gradient-based optimization. Changes to the FLORIS model were made to remove discontinuities and add curvature to regions of non-physical zero gradient. Exact gradients for the FLORIS model were obtained using algorithmic differentiation. A set of three case studies demonstrate that using …


Determining H2O Vapor Temperature And Concentration In Particle-Free And Particle-Laden Combustion Flows Using Spectral Line Emission Measurements, John Robert Tobiasson Jul 2017

Determining H2O Vapor Temperature And Concentration In Particle-Free And Particle-Laden Combustion Flows Using Spectral Line Emission Measurements, John Robert Tobiasson

Theses and Dissertations

There is a growing need for the clean generation of electricity in the world, and increased efficiency is one way to achieve cleaner generation. Increased efficiency may be achieved through an improved understanding of the heat flux of participating media in combustion environments. Real-time in-situ optical measurements of gas temperature and concentrations in combustion environments is needed. Optical methods do not disturb the flow characteristics and are not subject to the temperature limitation of current methods. Simpler, less-costly optical measurements than current methods would increase the ability to apply them in more circumstances. This work explores the ability to simultaneously …


Rebuilding Kidneys, Alonzo D. Cook, Deverly L. Roeder, Jonathan J. Wisco Jun 2017

Rebuilding Kidneys, Alonzo D. Cook, Deverly L. Roeder, Jonathan J. Wisco

Journal of Undergraduate Research

The motivation for this work was the tremendous need for replacement kidneys. End-stage renal disease (ESRD) affects over 500,000 patients in the U.S. and costs Medicare $30 Billion annually for dialysis and transplant procedures. Our overall objective was to engineer kidneys from decellularized porcine extracellular matrix (DPECM) scaffolds and cell cultures grown from human progenitor cells. The primary reason for using human cells was to develop non-immunogenic kidneys that can be used to treat the more than 100,000 chronic kidney disease (CKD) patients awaiting a transplant, thus obviating the need for post-transplant immunosuppressive therapy and the associated risks of acute …


Thermophysical Properties Of Thin Fibers Via Photothermal Quantum Dot Fluorescence Spectral Shape-Based Thermometry, Troy Munro, Liwang Liu, Heng Ban, Christ Glorieux Jun 2017

Thermophysical Properties Of Thin Fibers Via Photothermal Quantum Dot Fluorescence Spectral Shape-Based Thermometry, Troy Munro, Liwang Liu, Heng Ban, Christ Glorieux

Faculty Publications

To improve predictions of composite behavior under thermal loads, there is a need to measure the axial thermophysical properties of thin fibers. Current methods to accomplish this have prohibitively long lead times due to extensive sample preparation. This work details the use of quantum dots thermomarkers to measure the surface temperature of thin fibers in a non-contact manner and determine the fibers’ thermal diffusivity. Neural networks are trained on extracting the temperature of a sample from fluorescence spectra in calibrated, steady-state conditions, based on different spectral features such as peak intensity and peak wavelength. The trained neural networks are then …


An Analysis Of Enabling Techniques For Highly-Accessible Low-Cost Virtual Reality Hardware In The Collaborative Engineering Design Process, Joshua Q. Coburn Jun 2017

An Analysis Of Enabling Techniques For Highly-Accessible Low-Cost Virtual Reality Hardware In The Collaborative Engineering Design Process, Joshua Q. Coburn

Theses and Dissertations

While there currently exists a great deal of research in the literature demonstrating various engineering applications for virtual reality (VR) and the benefits of these applications, VR adoption has been slow in part because of the high cost and resources required to setup and maintain the hardware for these applications. However, in the last 5 years, a new generation of VR hardware has emerged with cost and resource requirements which are a small fraction of previous hardware. This work begins with a survey of this newly available hardware summarizing recent advances for providing virtual input to all of the five …


An Analysis Of Enabling Techniques For Highly-Accessible Low-Cost Virtual Reality Hardware In The Collaborative Engineering Design Process, Joshua Q. Coburn Jun 2017

An Analysis Of Enabling Techniques For Highly-Accessible Low-Cost Virtual Reality Hardware In The Collaborative Engineering Design Process, Joshua Q. Coburn

Theses and Dissertations

While there currently exists a great deal of research in the literature demonstrating various engineering applications for virtual reality (VR) and the benefits of these applications, VR adoption has been slow in part because of the high cost and resources required to setup and maintain the hardware for these applications. However, in the last 5 years, a new generation of VR hardware has emerged with cost and resource requirements which are a small fraction of previous hardware. This work begins with a survey of this newly available hardware summarizing recent advances for providing virtual input to all of the five …


Aerodynamic Drag On Intermodal Rail Cars, Philip Donovan Kinghorn Jun 2017

Aerodynamic Drag On Intermodal Rail Cars, Philip Donovan Kinghorn

Theses and Dissertations

The freight rail industry is essential to the US infrastructure and there is significant motivation to improve its efficiency. The aerodynamic drag associated with transport of commodities by rail is becoming increasingly important as the cost of diesel fuel increases. For intermodal railcars a significant amount of aerodynamic drag is a result of the large distance between containers that often occurs and the resulting pressure drag resulting from the separated flow that results due to their non-streamlined shape. This thesis reports on research that has been done to characterize the aerodynamic drag on intermodal train builds and allow their builds …


Microstructure Correlation With Formability For Biaxial Stretching Of Magnesium Alloy Az31b At Mildly Elevated Temperatures, David T. Fullwood, Isaac Chelladurai, Michael P. Miles, John E. Carsley, Raj K. Mishra, Irene J. Beyerlein, Marko Knezevic May 2017

Microstructure Correlation With Formability For Biaxial Stretching Of Magnesium Alloy Az31b At Mildly Elevated Temperatures, David T. Fullwood, Isaac Chelladurai, Michael P. Miles, John E. Carsley, Raj K. Mishra, Irene J. Beyerlein, Marko Knezevic

Faculty Publications

Magnesium AZ31B sheets of 2 mm thickness were stretch formed using a 101.6 mm diameter punch at temperatures from 25°C - 150°C, in 25°C increments. Surface strains were measured using a digital image correlation (DIC) method. The punch height vs load curve was found to be the same for temperatures of 25°C and for 50°C, while at 75°C and above the load for a given punch height started to decrease, indicating a potential change in deformation mechanism. Electron Backscatter Diffraction (EBSD) was used to quantify features of the microstructure in the tested specimens. In particular, the gradual decrease in twinning …


Computer-Aided Design Integration In Virtual Reality Design Reviews For Improved Interaction With Engineering Models, Ian James Freeman May 2017

Computer-Aided Design Integration In Virtual Reality Design Reviews For Improved Interaction With Engineering Models, Ian James Freeman

Theses and Dissertations

Leveraging virtual reality (VR) technology to enhance engineering design reviews has been an area of significant interest for researchers since the advent of modern VR. The ability to interact meaningfully with 3D engineering models in these VR design reviews is an important, though often neglected, capability due to the difficulty of performing data translation between native CAD data and VR compatible file formats. A bi-directional interface was developed between a VR design review environment and a commercial CAD package that streamlines the data translation process. By transmitting both geometric data and selected metadata from the CAD system an improved format …


Developing Hybrid Thickness-Accommodation Techniques For New Origami-Inspired Engineered Systems, Kyler Austin Tolman May 2017

Developing Hybrid Thickness-Accommodation Techniques For New Origami-Inspired Engineered Systems, Kyler Austin Tolman

Theses and Dissertations

Origami has become a source of inspiration in a number of engineered systems. In most systems, non-paper materials where material thickness is non-negligible is required. In origami-inspired engineered systems where thickness is non-negligible, thickness-accommodation techniques must be utilized to overcome the issue of self-intersection. Many thickness-accommodation techniques have been developed for use in thick-origami-inspired-engineered systems. In this work several thickness-accommodation techniques are reviewed and discussed. New thickness-accommodation techniques including hybrid thickness-accommodation techniques and the split vertex technique are presented and discussed. These techniques enable new capabilities of thickness-accommodation in origami adapted design. Thickness-accommodation techniques have been developed in the context …


Integration Of A Complete Detect And Avoid System For Small Unmanned Aircraft Systems, Jared Kevin Wikle May 2017

Integration Of A Complete Detect And Avoid System For Small Unmanned Aircraft Systems, Jared Kevin Wikle

Theses and Dissertations

For unmanned aircraft systems to gain full access to the National Airspace System (NAS), they must have the capability to detect and avoid other aircraft. This research focuses on the development of a detect-and-avoid (DAA) system for small unmanned aircraft systems. To safely avoid another aircraft, an unmanned aircraft must detect the intruder aircraft with ample time and distance. Two analytical methods for finding the minimum detection range needed are described. The first method, time-based geometric velocity vectors (TGVV), includes the bank-angle dynamics of the ownship while the second, geometric velocity vectors (GVV), assumes an instantaneous bank-angle maneuver. The solution …


Modeling Three Dimensional Ground Reaction Force Using Nanocomposite Piezoresponsive Foam Sensors, Parker Gary Rosquist May 2017

Modeling Three Dimensional Ground Reaction Force Using Nanocomposite Piezoresponsive Foam Sensors, Parker Gary Rosquist

Theses and Dissertations

Three dimensional (3D) ground reaction force (GRF) are an essential component for gait analysis. Current methods for measuring 3D GRF involve using a stationary force plate embedded in the ground, which captures the forces as subjects walk across the platform. This approach has several limitations, a few being: it can only capture a few steps at a time, it is expensive to purchase and maintain, it can't reflect forces caused by natural uneven surfaces, etc. Previous research has attempted to develop wearable force sensors to overcome these problems; however, these endeavors have resulted in devices that are expensive, bulky, and …


Thermal Characterization Of Natural And Synthetic Spider Silks By Both The 3Ω And Transient Electrothermal Methods, Troy Munro, Changhu Xing, Heng Ban, Cameron G. Copeland, Randolph V. Lewis, Colby Jensen Apr 2017

Thermal Characterization Of Natural And Synthetic Spider Silks By Both The 3Ω And Transient Electrothermal Methods, Troy Munro, Changhu Xing, Heng Ban, Cameron G. Copeland, Randolph V. Lewis, Colby Jensen

Faculty Publications

Thermal conductivity, thermal diffusivity and volumetric heat capacity of three spider silks are measured in this paper as a benchmark for further studies. These silks include the major and minor ampullate silks of the Nephila clavipes spider, and a synthetic spider silk fiber made from recombinant dragline silk proteins purified from transgenic goats’ milk. Two complementary measurement techniques are employed in the thermal characterization of these microscale single fibers for self-verification. One is the transient electrothermal technique (TET) and the other is the 3ω method. Experimental measurements indicate that thermal properties of the dragline silk are very close to those …


Investigation Of Synthetic Spider Silk Crystallinity And Alignment Via Electrothermal, Pyroelectric, Literature Xrd, And Tensile Techniques, Troy Munro, Tristan Putzeys, Michael Wubbenhorst, Christ Glorieux, Cameron G. Copeland, Randolph V. Lewis, Changhu Xing, Heng Ban Apr 2017

Investigation Of Synthetic Spider Silk Crystallinity And Alignment Via Electrothermal, Pyroelectric, Literature Xrd, And Tensile Techniques, Troy Munro, Tristan Putzeys, Michael Wubbenhorst, Christ Glorieux, Cameron G. Copeland, Randolph V. Lewis, Changhu Xing, Heng Ban

Faculty Publications

The processes used to create synthetic spider silk greatly affect the properties of the produced fibers. This paper investigates the effect of process variations during artificial spinning on the thermal and mechanical properties of the produced silk. Property values are also compared to the ones of the natural dragline silk of the N. clavipes spider, and to unprocessed (as-spun) synthetic silk. Structural characterization by scanning pyroelectric microscopy is employed to provide insight into the axial orientation of the crystalline regions of the fiber and is supported by XRD data. The results show that stretching and passage through liquid baths induce …