Mechanical Engineering Commons^™

Redeployment And Demonstration Of The Video Guidance Sensor For Proximity Maneuvers, Xiangyi Li

Theses and Dissertations

This paper presents the redeployment and demonstration of the Photogrammetric Video Guidance Sensor (PVGS) as a position and attitude sensor for proximity maneuvers and formation flight of small spacecraft. The original PVGS was developed to use a smartphone as its hardware and an Android application as its software; however, this paper provides a possibility for using a smaller and cheaper single-board computer, Raspberry Pi as new hardware, and for using a Java program run in Linux as its software. We finally achieved the approximate performance compared to the original PVGS. At the current stage, a PID controller was supposed to …

Merging Parallel-Plate And Levitation Actuators To Enable Linearity And Tunability In Electrostatic Mems, Mark Pallay, Ronald N. Miles, Shahrzad Towfighian

Mechanical Engineering Faculty Scholarship

In this study, a linear electrostatic MEMS actuator is introduced. The system consists of a MEMS cantilever beam with combined parallel-plate and electrostatic levitation forces. By using these two forcing methods simultaneously, the static response and natural frequency can be made to vary linearly with the voltage. The static response shows a linear increase of 90 nm/V and is maintained for more than 12μm of the tip displacement. The natural frequency shows a linear increase of 16 Hz/V and is maintained throughout a 2.9 kHz shift in the natural frequency. This wide range of linear displacement and frequency tunability is …

Development Of Prognostics Techniques For Surface Defect Growth In Railroad Bearing Rolling Elements, Nancy De Los Santos

Theses and Dissertations

One of the major causes of failure in railroad bearings used in freight service is rolling contact fatigue (RCF). RCF is due to subsurface inclusions which are a result from impurities in the steel that is used to fabricate the bearings. Once the bearings initiate subsurface fatigue cracks, they will then propagate upward and initiate spalling of the rolling surfaces. These spalls will begin small and continuously propagate with operation as this induces additional crack forming and spalling. Studies have indicated that bearing temperature is not a good indicator of spall initiation. In many cases, the temperature of the bearing …

Estimating The Outer Ring Defect Size And Remaining Service Life Of Freight Railcar Bearings Using Vibration Signatures, Joseph Montalvo, Constantine Tarawneh, Jennifer Lima, Jonas Cuanang, Nancy De Los Santos

Mechanical Engineering Faculty Publications

The railroad industry currently utilizes two wayside detection systems to monitor the health of freight railcar bearings in service: The Trackside Acoustic Detection System (TADS™) and the wayside Hot-Box Detector (HBD). TADS™ uses wayside microphones to detect and alert the conductor of high-risk defects. Many defective bearings may never be detected by TADS™ since a high-risk defect is a spall which spans more than 90% of a bearing’s raceway, and there are less than 20 systems in operation throughout the United States and Canada. Much like the TADS™, the HBD is a device that sits on the side of the …

Impact Of Cycloalkanes On Ignition Propensity Measured As Derived Cetane Number In Multi-Component Surrogate Mixtures, Dalton Odell Carpenter

Theses and Dissertations

Cycloalkanes are one type of hydrocarbons present in real jet fuels. The distinct cyclic structure of the cyclo-alkanes impacts the chemical kinetic behavior differently compared to n- and iso-alkanes. At high temperatures, thermal decomposition reactions dominate, producing n-alkyl radicals similar to the oxidation reactions of n-alkanes thus promoting the reactivity. Whereas in low temperatures, the presence of the ring structure essentially suppresses the formation of alkylhydroperoxy radicals (QOOH) from alkylperoxy radicals (RO2), thus exhibiting similar reactivity to iso-alkanes. In previous generations of surrogate fuels, the cyclo-alkane functional group were largely ignored due to low levels of cycloalkanes in traditional jet …

Enhancing Thermal-Hydraulic Performance Of Parallel And Counter Flow Mini-Channel Heat Sinks Utilizing Secondary Flow: A Numerical And Experimental Study, Amitav Tikadar

Theses and Dissertations

Continual growth of hydraulic and thermal boundary layers along stream wise direction in conventional straight fin mini-channel heat sink causes gradual deterioration of their thermal performance. To enhance thermal-hydraulic performance by breaking and redevelopment of the boundary layers, this research aims to introduce a novel inter-connected mini-channel sinks. Two inter-connectors were positioned transversely between two adjacent mini-channels, which segmented the flow domain into three zones. Secondary flow was generated through the inter-connectors utilizing the pressure difference of the adjacent channels resulting in hydraulic and thermal boundary layers disruption and hence enhanced thermal-hydraulic performance of the mini-channel heat sink was achieved. …

3d Topology Optimization Of Spatially Reinforced Composites, Luis G. Bahamonde Jácome

Theses and Dissertations

Topology optimization is a numerical design tool used to generate structural concepts that present optimal load paths for a given set of functional requirements. This functional generative design capability has been used to lightweight high performance structures with 1D, 2D and 3D stress states. On the other hand, fiber-reinforced composites are the perfect candidate material to use in high performance structures due to the tailorability of their stiffness and strength properties. Although numerical tools that simultaneously tailor the composite material properties while optimizing the structural topology exist, these tools are inherently limited to 1D and 2D stress states.

This work …

Mechanical Characterization And Non-Destructive Evaluation Of SicF/SicM Composites For Nuclear Applications, Donald J. Mccleeary

Theses and Dissertations

The SiC_f/SiC_m composite material is a promising candidate for accident tolerant fuel cladding in light water reactors and for structural elements in high temperature reactors. The material demonstrates exceptional toughness when compared to monolithic ceramics. It is critical to characterize the mechanical behavior, internal damage and ultimate strength of these composites under relevant loading conditions. In this thesis, the author developed and improved several mechanical characterization and non-destructive evaluation methods and applied them to SiC_f/SiC_m composites. Impulse excitation (IE) analysis of damaged SiC_f/SiC_m composite disks following controlled impact testing shows a …

A Model For Condensation Heat Transfer In Hydrophobic-­Hydrophilic Surfaces, Abdulwahab E. Alhashem

Theses and Dissertations

The primary focus of this research is to provide a validated model for a comprehensive understanding of hydrophobic-­‐hydrophilic condensation on patterned-­‐ hybrid surface. Establishing the model requires the modeling of fully dropwise condensation (DWC) before applying modifications to evaluate heat transfer performance of patterned-­‐hybrid condensation surface.

The model for fully DWC consists of defining expressions for heat transfer through a single drop, maximum radius of the drop and drop-­‐size distribution which all are primarily based on the work in the literature. In this work the author utilized a proposed modified version of the simulation for drop-­‐size distribution for fully DWC, …

A Coastal Estuarine Ensemble Forecasting System, Peyman Taeb

Theses and Dissertations

This research has been conducted in an effort to reduce the computational costs associated with high-resolution coastal estuarine modeling in ADCIRC. It was proposed that model scalability will be significantly enhanced if the conventional single-domain technique is replaced by a nesting method. Preliminary testing indicated the potential for 50% to more than 80% simulation runtime reduction (depending on the study site) by implementing a nesting technique. Once the concept was proved, the development of an operational, ensemble-based forecasting system, exclusively for the east coast of Central Florida and the IRL system, was implemented. The system, referred to as Ensemble Multistage, …

Surrogate Formulation Based On Chemical Functional Group Analysis, Stuart Nates

Theses and Dissertations

Chemical kinetic characteristics of real fuels exhibit high-dimensional complexity due to the excessive number of molecules and molecular classes. As a method of projecting this high-dimensional complexity, which is pertinent to real fuels, to the low-dimensional description, either a surrogate approach or detailed experiments have been utilized, can guide the construction of chemical kinetic models for real fuel. Although the validity of the surrogate approach has been extensively demonstrated by a wide range of canonical experiments for whole fuel/air mixtures, the use of empirical fuel property indicators still worries whether or not the surrogate mixture truly captures the more complex …

Developing An Interview Protocol For An Engineering Design Capstone Course To Measure Student Motivation And Engineering Identity, Mckenzie Clark

Theses and Dissertations

This thesis examines the process of developing an effective in-depth interview protocol to measure student motivation and engineering identity. Several methods were employed during the creation, refining, and analysis portions of this study to ensure reliability and validity of the qualitative research instrument. In a multifaceted course such as senior capstone design, it is integral to ensure students are receiving a value adding experience. In most universities across the United States, senior capstone design is a multiple semester sequence where design is heavily emphasized and students are encouraged to test their skills, both technical and nontechnical, by solving and implementing …

Advancing Numerical Calculation Of Mixed Sized Sediment Transport And Morphology Change, Irene Margaret Watts

Theses and Dissertations

Numerical modeling of sediment transport and morphologic change has become a powerful tool for studying and working in the coastal zone. Numerical calculation can assist in a broad range of projects from regional sediment management to beach nourishment as well as evaluating environmental aspects of dredging and placement and implications to water quality and turbidity. Success in application of these tools is partially dependent on the quality of characterization of the sediments in the field. These parameters could include grain size, mineralogical composition, specific gravity and fall velocity. Sediment transport formulations are sensitive to the spatial representation of the sediments …

Unsupervised-Learning Assisted Artificial Neural Network For Optimization, Varun Kote

Mechanical & Aerospace Engineering Theses & Dissertations

Innovations in computer technology made way for Computational Fluid Dynamics (CFD) into engineering, which supported the development of new designs by reducing the cost and time by lowering the dependency on experimentation. There is a further need to make the process of development more efficient. One such technology is Artificial Intelligence. In this thesis, we explore the application of Artificial Intelligence (AI) in CFD and how it can improve the process of development.

AI is used as a buzz word for the mechanism which can learn by itself and make the decision accordingly. Machine learning (ML) is a subset of …

Computational Analysis And Design Optimization Of Convective Pcr Devices, Jung Il Shu

Mechanical & Aerospace Engineering Theses & Dissertations

Polymerase Chain Reaction (PCR) is a relatively novel technique to amplify a few copies of DNA to a detectable level. PCR has already become common in biomedical research, criminal forensics, molecular archaeology, and so on. Many have attempted to develop PCR devices in numerous types for the purpose of the lab-on-chip (LOC) or point-of-care (POC). To use PCR devices for POC lab testing, the price must be lower, and the performance should be comparable to the lab devices. For current practices with the existing methods, the price is pushed up higher partially due to too much dependence on numerous developmental …

Nonlinear Direct Torque Control Of Interior Permanent Magnet Synchronous Motor Drive, Jackson Justo

Tanzania Journal of Engineering and Technology (TJET)

This paper presents a nonlinear direct torque control (NDTC) strategy of interior permanent magnet synchronous motors (IPMSMs) for electric vehicle (EV) propulsion. The proposed NDTC scheme applies a nonlinear model of IPMSM to dynamically determine the optimal switching states that optimize the EV drivers’ decision to reduce the workload. Moreover, the proposed NDTC method has a simple control structure and can explicitly handle system constraints and nonlinearities. The performance evaluation is conducted via a prototype IPMSM test-bed with a TMS320F28335 DSP. Comparative experimental results provide the evidence of improvements of the proposed NDTC strategy over the conventional DTC strategy by …

Potential Use Of High Rate Algae Ponds For Resource Recovery In The Water-Food-Energy Nexus For Tanzania: A Review, Mary Kayombo

Tanzania Journal of Engineering and Technology (TJET)

The use of High Rate Algal Ponds (HRAPs) for the treatment of wastewater and resource recovery has raised interest in recent years. Treatment of wastewater through this technology has proved to have high efficiency in reducing the level of pollution, nutrients, dissolved solids as well as pathogens. HRAPs are more efficient than conventional Wastewater Stabilization Ponds (WSPs) due to their design approach that provides room for high rate bio-chemical processes, which increase the mechanisms of nutrients and pathogens removal as well as the rate of micro-algae production for purposes of resource recovery. This paper reviews the upgrading potential of existing …

The Comparative Analysis Of The Performances Of Four And Six Pole Pairs Permanent Magnet Synchronous Generator, Ra Msuya

Tanzania Journal of Engineering and Technology (TJET)

Wind power applications using multi-poles permanent magnet generators have become very attractive especially in small ratings. Low-speed multi-pole PM generators are maintenance-free and may be used in different climate conditions. Most of the low speed wind turbine generators presented is permanent magnet machines, which have advantages of high efficiency and reliability since there is no need of external excitation and conductor losses are removed from the rotor. From the study two types of PM AC generator are designed with 6 pole pairs and the other one with 4 pole pairs. These generators were designed and analysed using Maxwell software. The …

The Effect Of Radial Head Hemiarthroplasty Stem Fit On Radiocapitellar Contact Mechanics: Is Loose Fit Better Than Rigidly Fixed?, Jakub Szmit, Graham J.W. King, James A. Johnson, G. Daniel G. Langohr

Western Research Forum

Background/Methods: Radial head hemiarthroplasty is commonly employed to manage comminuted displaced fractures. With regards to implant fixation, current designs vary with some prostheses aiming to achieve a tight 'fixed' fit, and others utilizing a smooth stem with an over reamed 'loose' fit. The purpose of the present study was to evaluate the effect of radial head hemiarthroplasty stem fit on radiocapitellar contact using a finite element model which simulated both fixed (size-for-size) and loose (1, 2 & 3mm over reamed) stem fits.

Hypothesis: It was hypothesized that a loose stem fit would improve radiocapitellar contact mechanics, with increased contact area …

Investigating The Effect Of Stiffness In Hemiarthroplasty Implants, Carolyn Berkmortel, Daniel Langohr, Graham King, James Johnson

Western Research Forum

Background: Hemiarthroplasty is an attractive alternative to total arthroplasty because it conserves tissue, allows for quicker recovery, and has a lower cost. However, likely due to the high stiffness of the implant, hemiarthroplasties often lead to accelerated wear of the opposing native cartilage.

Hypothesis and Methods: The purpose of this study was to investigate the maximum contact stress on the capitellum for different currently available biomaterials in radial head hemiarthroplasty and compare them to the native radial head. A finite element model was developed in ABAQUS (Dassault Systèmes Simulia Corp., RI, USA). An axial load of 100N was applied to …

Lansce Diagnostic Robot Localization, Lucas S. Montoya

Mechanical Engineering ETDs

Los Alamos Neutron Science Center (LANSCE) operates a linear particle accelerator (LINAC) that is used for a number of scientific research projects. Due to the presence of harmful radiation, researchers are not allowed in the beam tunnel during operation. Since the beam tunnel is inaccessible, an autonomous mobile robot is to be developed and deployed in the tunnel, monitoring the accelerator during operation. The robot will present real time data for operators and scientists from sensors such as a video camera, thermal camera, microphones, and muon detectors; allowing for beam diagnostics previously unavailable.

Localization is a fundamental step in autonomous …

A Soft-Robotic Harbor Porpoise Pectoral Fin Driven By Coiled Polymer Actuators As Artificial Muscles, Robert Hunt, Sarah Trabia, Zakai Olsen, Kwang Kim

Mechanical Engineering Faculty Research

Biomimicry is an approach in science and engineering to overcome human challenges by designing materials and systems modeled after nature. Selected applications of biomimicry include catheters, hearing devices, and artificial appendages such as arms, legs, and fingers. The inspiration for this study is the hydrofoil-like structured pectoral fin of the harbor porpoise whale that is ultimately useful for studying fluid-structure interactions, drag, lift, and laminar-to-turbulent transitions. The pectoral fin is fabricated by manipulating computed tomography (CT) scans into 3D models using Simpleware ScanIP and post-processed in Autodesk for printing. An array of thermally driven coiled polymer actuators (CPA) fabricated from …

Graphs And Cad: Analyzing The Experience Of A Mechanical Engineering Intern, Matthew Des Biens

Celebration of Learning

A reflection on the experiences of a mechanical engineering intern at Bergstrom Inc., this presentation, by Senior Matt Des Biens, will discuss what it was like working for a manufacturing and design company making HVAC units for large customers across the world. The highlights will be on the projects he worked on, the things that he learned, and his views on working for the company as a whole.

Experimental And Theoretical Evaluation Of The Effect Of Panel Geometry On The Failure Of Corrugated Board Panel, Takashi Takayama, Katsuhiko Saito, Akira Higashiyama

Journal of Applied Packaging Research

McKee’s formula is widely used to predict the compression strength (CS) of corrugated boxes and panels. It can accurately estimate the compression strength of boxes that are within a practical size range, but recently, larger and smaller corrugated boxes than before have been extensively developed. Therefore, there is a need for a CS prediction formula that works beyond the application range of McKee’s formula. Recent researches consider the failure mode as a combination of collapsing and buckling failure and remove the constraints and the assumptions associated with McKee’s formula. This makes it possible to more accurately estimate the CS of …

Generating Electrospray From A Ferrofluid, Lyon Bradley King

Michigan Tech Patents

An electrospray device for generating electrospray from a ferrofluid. The electrospray device includes an emitter, an extraction electrode, and a magnet. The emitter is configured to receive a ferrofluidic liquid. The extraction electrode includes an aperture and is positioned a first distance from the emitter. The magnet generates a magnetic field in a first direction toward the emitter. The magnetic field causes Rosensweig instability in the ferrofluidic liquid, and generates a ferrofluidic peak in the ferrofluidic liquid. The magnet is positioned a second distance from the emitter, and the emitter is positioned between the extraction electrode and the magnet. The …

On Distributed Control Of Multiagent Systems Under Adverse Conditions, Emre Yildirim

USF Tampa Graduate Theses and Dissertations

The objective of this thesis is (1) to show the experimental validation of recently proposed distributed adaptive control architecture for a class of heterogeneous uncertain multiagent systems as well as (2) to theoretically propose a proportional integral controller for multiagent systems having limited resources in the presence of a disturbance with stability analyses.

With regard to (1), the distributed adaptive control architecture used in the experiment utilizes a control input having a nominal part and an adaptive augmentation part for each agent to suppress the effect of uncertainties and disturbances effectively. This architecture is capable to provide uniform ultimate boundedness …

Algal Remediation Of Wastewater Produced From Hydrothermally Treated Septage, Kyle Mcgaughy, Ahmad Abu Hajer, Edward Drabold, David J. Bayless, M. Toufiq Reza

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Hydrothermal carbonization (HTC) is a promising technology to convert wet wastes like septic tank wastes, or septage, to valuable platform chemical, fuels, and materials. However, the byproduct of HTC, process liquid, often contains large amount of nitrogen species (up to 2 g/L of nitrogen), phosphorus, and a variety of organic carbon containing compounds. Therefore, the HTC process liquid is not often treated at wastewater treatment plant. In this study, HTC process liquid was treated with algae as an alternative to commercial wastewater treatment. The HTC process liquid was first diluted and then used to grow Chlorella sp. over a short …

Noise Threshold And Normalization By Contrast Parameter For Atomization During Droplet Impingement, Alexander White, Julie Crockett

Journal of Undergraduate Research

The purpose of this report is to remind the reader of goals initially set in conjunction with the original ORCA Grant project proposal in October 2017, to discuss logistical difficulties in carrying out the original project and subsequent adjustments in scope and topic of work, to represent efforts toward obtaining results during the grant period, and to comment on the implications of the study for future research and the award’s impact on its recipient’s future.

Proof-Of-Concept Tremor Suppression Sleeve For Essential Tremor Patients, S. Adam Stringham, Dr. Steven K. Clarles

Journal of Undergraduate Research

Essential Tremor (ET) is among the most common movement disorders. It is characterized by involuntary, rhythmic movement in the body, most often in the hands or head. The primary treatment options include deep brain surgery and/or medication, both of which can cause undesired side effects. The Neuromechanics Research Group at BYU is investigating alternative treatments by studying the effect of low-level electrical stimulation of affected extrinsic hand muscles on tremor in ET patients. While the research may prove promising, there are still several obstacles to overcome for this approach to be practical. To apply electrical stimulation, self-adhesive electrodes are placed …

Gas Detection System For Biomass Cookstove Emissions, Jeffery Smith, Cyera Bishop, Matthew Jones

Journal of Undergraduate Research

The purpose of this research project was to explore Peruvian social and cultural behaviors that typically prevent successful improved cookstove adoption in resource-limited settings as well as suggest ways to educate locals about the benefits of improved cookstoves. This will be done by a BYU Global Engineering Outreach (GEO) team, including ORCA recipients Cyera Bishop and Jeffery Smith, constructing a cost-effective, easy-to-use gas detection sensor system capable of measuring concentrations of harmful gases released from biomass cookstoves typically found in Peruvian communities.