Mechanical Engineering Commons^™

Energy Harvesting & Recapture From Human Subjects: Dual-Stage Mems Cantilever Energy Harvester, Nicholas P. Sullivan

Theses and Dissertations

Recent thermal energy harvesting research has advanced alternative non-Seebeck devices and shifted attention towards applications with low temperature differentials near ambient. This research effort takes a simulation-based approach to improve the performance of a modified dual-stage MEMS cantilever energy harvester. The device employs a bimetal and a piezoelectric transducer to harvest energy from a 10° C temperature differential. The proposed application for the device is as a wearable energy harvester, capable of generating power from the human body using skin temperature (average 33° C) as the hot side and ambient air (23° C) as the cold side. A bimetal thickness …

Investigation Of The High-Cycle Fatigue Life Of Selective Laser Melted And Hot Isostatically Pressed Ti-6al-4v, Kevin D. Rekedal

Theses and Dissertations

Experimental research was conducted on the effectiveness of Hot Isostatic Pressing (HIP) to improve the high-cycle fatigue life of Selective Laser Melted Ti-6Al-4v (SLM Ti-64). A thorough understanding of the fatigue life performance for additively manufactured parts is necessary before such parts are utilized in an operational capacity in Department of Defense (DoD) systems. Such applications include the rapid, on-demand fabrication of replacement parts during contingency operations or the production of light-weight topology-optimized components. This research assesses the fatigue life of SLM Ti-64 test specimens built directly to net dimensions without any subsequent surface machining. The configuration is designed as …

Experimental Magnetohydrodynamic Energy Extraction From A Pulsed Detonation, Kaz I. Teope

Theses and Dissertations

The high MWatt power available in a fuel-fed detonation wave, which contains combustion ions in the trailing gas, provides an opportunity for external power extraction via electromagnetically forced charged particle drift. Sets of experiments were accomplished using a pulsed detonation tube, extracting power across a load resistor in an electrical circuit with an applied electric or magnetic field to determine what magnitude of gas conductivity and power extraction could be attained from an unseeded or seeded pulsed detonation driven combustion. Due to the low magnetic field strength, even with flow seeding, the power extracted in this research was not enough …

Vortex Identification In The Wake Of A Wind Turbine Array, Aleksandr Sergeyevich Aseyev

Dissertations and Theses

Vortex identification techniques are used to analyze the flow structure in a 4 x 3 array of scale model wind turbines. Q-criterion, Δ-criterion, and λ₂-criterion are applied to Particle Image Velocimetry data gathered fore and aft of the last row centerline turbine. Q-criterion and λ₂-criterion provide a clear indication of regions where vortical activity exists while the Δ-criterion does not. Galilean decomposition, Reynolds decomposition, vorticity, and swirling strength are used to further understand the location and behavior of the vortices. The techniques identify and display the high magnitude vortices in high shear zones resulting from the …

An Experimental Study On Passive Dynamic Walking, Philip Andrew Hatzitheodorou

USF Tampa Graduate Theses and Dissertations

In this study, a previously designed passive dynamic walker (PDW) is built out of aluminum and plastic. The aim of the study was to produce an asymmetrical PDW and to compare the results to a computer simulation to validate the mathematical model. It also aimed at identifying the limitations of using additive manufacturing to create components for a PDW as well as gain insights on asymmetric systems.

Beginning with a five mass kneed model, parameters were varied to produce up to a nine mass kneed model solution. The nine mass model allows more variability in added mass locations and separates …

Plastic Deformation Of A Model Glass Induced By A Local Shear Transformation, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The effect of a local shear transformation on plastic deformation of a three-dimensional amorphous solid is studied using molecular dynamics simulations. We consider a spherical inclusion, which is gradually transformed into an ellipsoid of the same volume and then converted back into the sphere. It is shown that at sufficiently large strain amplitudes, the deformation of the material involves localized plastic events that are identified based on the relative displacement of atoms before and after the shear transformation. We find that the density profiles of cage jumps decay away from the inclusion, which correlates well with the radial dependence of …

Parameters Identification For A Composite Piezoelectric Actuator Dynamics, Mohammad Saadeh, Mohamed Trabia

Mechanical Engineering Faculty Research

This work presents an approach for identifying the model of a composite piezoelectric (PZT) bimorph actuator dynamics, with the objective of creating a robust model that can be used under various operating conditions. This actuator exhibits nonlinear behavior that can be described using backlash and hysteresis. A linear dynamic model with a damping matrix that incorporates the Bouc–Wen hysteresis model and the backlash operators is developed. This work proposes identifying the actuator’s model parameters using the hybrid master-slave genetic algorithm neural network (HGANN). In this algorithm, the neural network exploits the ability of the genetic algorithm to search globally to …

A Technical And Economic Comparative Analysis Of Sensible And Latent Heat Packed Bed Storage Systems For Concentrating Solar Thermal Power Plants, Jamie Trahan

USF Tampa Graduate Theses and Dissertations

Though economically favorable when compared to other renewable energy storage technologies, thermal energy storage systems for concentrating solar thermal power (CSP) plants require additional cost reduction measures to help transition CSP plants to the point of grid-parity. Thermocline packed bed storage is regarded as one potential low cost solution due to the single tank requirement and low cost storage media. Thus sensible heat storage (SHS) and latent heat storage (LHS) packed bed systems, which are two thermocline varieties, are frequently investigated. LHS systems can be further classified as single phase change material (PCM) systems or cascaded systems wherein multiple PCMs …

Global Time-Independent Agent-Based Simulation For Transactive Energy System Dispatch And Schedule Forecasting, Shawn Aaron Chandler

Dissertations and Theses

Electricity service providers (ESP) worldwide have increased their interest in the use of electrical distribution, transmission, generation, storage, and responsive load resources as integrated systems. Referred to commonly as "smart grid," their interest is driven by widespread goals to improve the operations, management and control of large-scale power systems. In this thesis I provide research into a novel agent-based simulation (ABS) approach for exploring smart grid system (SGS) dispatch, schedule forecasting and resource coordination. I model an electrical grid and its assets as an adaptive ABS, assigning an agent construct to every SGS resource including demand response, energy storage, and …

Structural Integrity Of Conventional And Modified Railroad Bearing Adapters For Onboard Monitoring, Joseph Montalvo, Alexis Trevino, Arturo A. Fuentes, Constantine Tarawneh

Mechanical Engineering Faculty Publications

This paper presents a detailed study of the structural integrity of conventional and modified railroad bearing adapters for onboard monitoring applications. Freight railcars rely heavily on weigh bridges and stations to determine cargo load. As a consequence, most load measurements are limited to certain physical railroad locations. This limitation provided an opportunity for an optimized sensor that could potentially deliver significant insight on bearing condition monitoring as well as load information. Bearing adapter modifications (e.g. cut outs) were necessary to house the sensor and, thus, it is imperative to determine the reliability of the modified railroad bearing adapter, which will …

The Development Of An Adaptive Driving Simulator, Sarah Marie Tudor

USF Tampa Graduate Theses and Dissertations

The ability to drive a car is an important skill for individuals with a spinal cord injury to maintain a high quality of life, particularly their freedom and independence. However, driving with a physical disability often requires the installation of an adaptive driving system to control steering, gas, and braking. The two main types of adaptive driving controls are mechanical and electrical, also known as drive by wire (DBW). DBW controls work by converting electric signals to mechanical actuators. Driving simulators are useful tools for adaptive driving systems because they allow users to test different control devices, to practice driving …

Carbon Dioxide (Co2) Emissions, Human Energy, And Cultural Perceptions Associated With Traditional And Improved Methods Of Shea Butter Processing In Ghana, West Africa, Emily Adams

USF Tampa Graduate Theses and Dissertations

The shea tree is indigenous to 21 countries in Sub-Saharan Africa and provides nuts from which oil (referred to as butter) can be extracted. Shea butter production in the Northern Region of Ghana is of socioeconomic importance to female processors who practice shea production. This study quantified the environmental effects of shea processing from carbon dioxide emissions and the human energy expended through the traditional, improved, and centralized methods of shea processing. Par-boiling accounted for up to 88% of total carbon dioxide emissions throughout the entire shea butter production process. A difference of 2.5(CO₂ (kg))/(Shea butter (kg)) emitted observed …

Viability Of Bismuth As A Green Substitute For Lead In Jacketed .357 Magnum Revolver Bullets, Joel A. Jenkins

USF Tampa Graduate Theses and Dissertations

In seeking to develop environmentally friendly lead-free non-toxic bullets, the research ballistically evaluated the performance of copper-jacketed handgun bullets containing a pure bismuth core. The lead was first removed from 140 grain Hornady^TM XTP® bullets of 38 caliber (.357 diameter) by melting. The empty jackets were then refilled with pure bismuth, including the forming of a correctly sized hollow-point cavity. Due to the lower density of bismuth as compared to lead, the bismuth-cored bullets consistently weighed 125 gains. Conveniently this allowed direct comparison to commercially available 125 grain Hornady^TM XTP® lead-cored bullets of 38 caliber. Both bismuth-cored and …

Synthesis, Characterization, And Electrochemical Properties Of Polyaniline Thin Films, Soukaina Rami

USF Tampa Graduate Theses and Dissertations

Conjugated polymers have been used in various applications (battery, supercapacitor, electromagnetic shielding, chemical sensor, biosensor, nanocomposite, light-emitting-diode, electrochromic display etc.) due to their excellent conductivity, electrochemical and optical properties, and low cost. Polyaniline has attracted the researchers from all disciplines of science, engineering, and industry due to its redox properties, environmental stability, conductivity, and optical properties. Moreover, it is a polymer with fast electroactive switching and reversible properties displayed at low potential, which is an important feature in many applications. The thin oriented polyaniline films have been fabricated using self-assembly, Langmuir-Blodgett, in-situ self-assembly, layer-by-layer, and electrochemical technique. The focus of …

Adjustable Jig And Method For Targeting Interlocking Holes Of An Intramedullary Nail, Patrick J. Atkinson

Mechanical Engineering Patents

A targeting jig apparatus for targeting interlocking holes of an intramedullary nail. The targeting jig includes a support-arm extending substantially parallel to the intramedullary nail. A targeting mechanism including a pair of targeting mechanism drioll-guide orifices is adjustably disposed on the support arm for aligning the targeting mechanism drilol-guide orifice with the interlocking holes of the intramedullary nail. The targeting mechanism includes a saddle having a U-shape including a base and parallel legs that are slidable along the support-arm. A connection mechanism includes a horizontal slot on the support-arm aligned with a vertical slot on the targeting mechanism and a …

Methods And Systems For Handling Or Delivering Materials For Natural Orifice Surgery, Carl Nelson, Jeff Midday, Dimitry Oleynikov, Alan Goyzueta

Department of Mechanical and Materials Engineering: Faculty Publications

The embodiments disclosed herein relate to various medical systems, including systems that can be used in conjunction with medical devices used in endoscopic surgery. Certain embodiments include various material handling devices that can transport materials between the inside and the outside of an endoscopic surgery patient.

Creating A User-Friendly Personal Wine Collection Inventory Management System, Peter Loddengaard

Industrial and Manufacturing Engineering

This project set out to create a user-friendly wine collection management software. Existing systems were reviewed and discussions with collectors took place to establish the user requirements for this type of inventory management system. This led to the scope of the project being narrowed to making a wine bottle entry form that was quick and easy to use. The programming language, Ruby on Rails, was used to design this system, and learning the software was a large part of the project itself. It was established that four forms would be designed using combinations of two ergonomic factors: an “F” shaped …

Wasco Environmental Chamber System Manifold, Steve Mark Yatco

Industrial and Manufacturing Engineering

This report details the process of designing and producing a manifold that connects ultra-high purity (UHP) pressure and vacuum switches to an air supply so that the parts may be tested in an environmental chamber. Using the DMAIC (define, measure, analyze, improve, and control) methodology of problem solving, progress on the project includes thorough research about the problem, preliminary design solutions, iterative prototyping, and testing specific functionalities. Manufacturing engineering topics of tooling, fixturing, metrology, quality, and machining with manual and computer numerical control (CNC) varieties of both mills and lathes are applied during the course of the project. The report …

Frito-Lay - Supply Chain Impact Analysis, Kerri Blosch, Vincent Phua, Jeffrey Silva

Industrial and Manufacturing Engineering

The snack food company Frito-Lay relies on Route Sales Representatives (RSRs) to stock and maintain shelves of snack foods in every store. Frito-Lay currently does not have a system which can accurately predict cannibalization, or the effects of a store opening or closing on other stores of the same chain in the area. The goal is to sort through 1900 stores in a given metropolitan area to see the effects of cannibalization. In order to tackle the problem, a Microsoft Access program was created to filter stores based on location or whether the store was open for the full three-year …

Process Testing And Improvement Of Tapping Machinery At Lisi Aerospace, Michael James Hester

Industrial and Manufacturing Engineering

This report documents my senior project for California Polytechnic State University San Luis Obispo. I have chosen to do a senior project with Lisi Aerospace. Lisi would like to compare the manufacturer rated cycle count of taps versus an experimental one based on our machines in house. My goal for this project would be to run an experiment on one tapping machine and report on the achievable cycle count for the taps. I plan to do this in several ways including:

• Running extra cycle counts above tap manufacturer recommendations

• Documenting machine failure modes

• Create a process document to be repeated …

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Improving Advertisement Recognition And User Interface Of Gameofwarrealtips.Com, Chad Kihm, Alexander Meyer

Industrial and Manufacturing Engineering

The purpose of this experiment was to determine which location of advertisement would be the most recognized on the Game of War Real Tips website and to improve the website’s user interface by using both quantitative and qualitative data. To accomplish this, two experiments were created. The first experiment was designed to determine which location of advertisement would be recognized most by users. A screen would flash for 0.5 seconds and the subjects would mark where they believed they recognized an advertisement. A statistical analysis was completed to determine whether the location of the advertisement had an effect on the …

Advancing Biomechanical Research Through A Camelid Model Of The Human Lumbar Spine, Dean K. Stolworthy

Theses and Dissertations

The increasing incidence of disc degeneration and its correlation with lower back pain is an alarming trend in modern society. The research of intervertebral disc degeneration and low back pain would greatly benefit from additional methods to study its etiology and possible treatment methods. A large animal model that maintains the biological and mechanical environment that is most similar to the human lumbar spine could provide substantial improvements in understanding and resolving the problem of intervertebral disc related low back pain.This dissertation presents my doctoral work of investigating the potential for the camelid cervical spine to serve as a suitable …

Vision Based Multiple Target Tracking Using Recursive Ransac, Kyle Ingersoll

Theses and Dissertations

In this thesis, the Recursive-Random Sample Consensus (R-RANSAC) multiple target tracking (MTT) algorithm is further developed and applied to video taken from static platforms. Development of R-RANSAC is primarily focused in three areas: data association, the ability to track maneuvering objects, and track management. The probabilistic data association (PDA) filter performs very well in the R-RANSAC framework and adds minimal computation cost over less sophisticated methods. The interacting multiple models (IMM) filter as well as higher-order linear models are incorporated into R-RANSAC to improve tracking of highly maneuverable targets. An effective track labeling system, a more intuitive track merging criteria, …

Net Zero Residential Design For Solar Calpoly, Bryce Reiko Willis

Master's Theses

The Department of Energy (DOE) confirmed Team Solar Cal Poly from California Polytechnic State University, San Luis Obispo, as a competitor in the 2015 Solar Decathlon in February 2014. The Solar Decathlon is a biennial collegiate competition to construct a net-zero home and operate it for a week of “normal use”. Solar Cal Poly needed assistance with passive and active HVAC systems for the design, and thermal load models. The competition will take place in Irvine, CA [33.67⁰, 117.82⁰ W] from September 27 – October 3, 2015. After the completion, a potential final location for the house will be Santa …

Development Of An Autonomous Single-Point Calibration For A Constant Voltage Hot-Wire Anemometer, Ryan Murphy

Master's Theses

Traditionally, the measurement of turbulence has been conducted using hot-wire anemometry. This thesis presents the implementation of a constant voltage hot-wire anemometer for use with the Boundary Layer Data System (BLDS). A hot-wire calibration apparatus has been developed that is capable of operation inside a vacuum chamber and flow speeds up to 50 m/s. Hot-wires operated with a constant-voltage anemometer (CVA) were calibrated at absolute static pressures down to 26 kPa. A thermal/electrical model for a hot-wire and the CVA circuit successfully predicted the measured CVA output voltage trend at reduced pressure environments; however, better results were obtained when the …

Vibration-Based Health Monitoring Of Rotating Systems With Gyroscopic Effect, Nenad Gavrilovic

Master's Theses

This thesis focuses on the simulation of the gyroscopic effect using the software MSC Adams. A simple shaft-disk system was created and parameter of the sys-tem were changed in order to study the influence of the gyroscopic effect. It was shown that an increasing bearing stiffness reduces the precession motion. Fur-thermore, it was shown that the gyroscopic effect vanishes if the disk of system is placed symmetrically on the shaft, which reduces the system to a Jeffcott-Ro-tor. The second objective of this study was to analyze different defects in a simple fixed axis gear set. In particular, a cracked shaft, …

Wine Club Shipment Package Redesign, Emily E. Prescott

Industrial and Manufacturing Engineering

This report shows the design, manufacturing, and testing process for the product development of a wine club shipment package for Niner Wine Estates. Niner has two different shipment sizes, 4 bottles and 6 bottles, and wishes to improve their current package by giving it a more “high-class” feel. After the new package was designed and prototyped, it went through standardized quality testing to be cleared for commercial use. This testing is intended to simulate the distribution cycle the package will experience and subject it to potential hazards such as being dropped and vehicle vibration during transportation.

After the package passed …

Three-Dimensional Flow Measurements Around A Mechanical Flapping Wing, Eric R. Hardester

Theses and Dissertations

Man has always been fascinated by the flight of birds and insects. First attempts at flight involved flapping wings to mimic the birds and insects that had been observed in flight. Fixed wings proved to be a more practical approach and have been used for over 100 years for manned flight. Emphasis has been placed on flapping wing designs for micro air vehicles (MAVs) as research has shown that challenges arise in lift generation and stability in fixed wing flight as the scale decreases [1].This research explores the use of 3D, time-resolved, Synthetic Aperture PIV (SAPIV) in measuring flow velocities …

Deployable And Foldable Arrays Of Spatial Mechanisms, Thomas Evans

Theses and Dissertations

This work evaluates a specific origami device known as the kaleidocycle and the broad classof rigidly foldable origami. Both of these have potential for application in the design of deployableand foldable arrays of spatial mechanisms.Origami is considered a compliant mechanisms because it achieves its motion through thedeflection of paper creases. Compliant mechanisms generally do not allow for continuous rotation;however, the compliant kaleidocycle represents an exception to this generality. Along with theirability to rotate continuously, kaleidocycles may also be designed to exhibit multistable behaviorduring this rotation. These two characteristics make the kaleidocycle an interesting device withpotential for applications in engineering. This …

Deformation Twin Nucleation And Growth Characterization In Magnesium Alloys Using Novel Ebsd Pattern Analysis And Machine Learning Tools, Travis Michael Rampton

Theses and Dissertations

Deformation twinning in Magnesium alloys both facilitates slip and forms sites for failure. Currently, basic studies of twinning in Mg are facilitated by electron backscatter diffraction (EBSD) which is able to extract a myriad of information relating to crystalline microstructures. Although much information is available via EBSD, various problems relating to deformation twinning have not been solved. This dissertation provides new insights into deformation twinning in Mg alloys, with particular focus on AZ31. These insights were gained through the development of new EBSD and related machine learning tools that extract more information beyond what is currently accessed.The first tool relating …