Mechanical Engineering Commons^™

A Study Of The Cause Of Failure Of Rotationally Molded, High-Density Polyethylene, Sodium Hypochlorite Storage Tanks, Dixon Harold Abell

Theses and Dissertations

The topic of chemical oxidative degradation in rotational molded polyethylene (high-density cross-linked) chemical (sodium hypochlorite) storage tanks is an industry problem that ranks at the top of current business issues for manufacturers of chemical storage tanks. The degradation of these tanks not only compromises the physical and mechanical properties of the tank material, but reduces the life expectancy of the tank, eventually resulting in catastrophic tank failure. Premature tank failure comes at a hefty cost. The reputation of the manufacturer is questioned often resulting in immediate loss of customer satisfaction and future business. The leaking of the chemical from the …

High-Resolution, Non-Contact Angular Measurement System For Psa/Rsa, Ronald D. Sloat

Master's Theses

A non-contact angular measurement system for Pitch Static Attitude (PSA) and Roll Static Attitude (RSA) of hard disk drive sliders is designed and built. Real-time sampling at over 15 KHz is achieved with accuracy of +/- 0.05 degrees over a range of approximately 2-3 degrees. Measuring the PSA and RSA is critical for hard drive manufacturers to control and improve the quality and reliability of hard drives. Although the hard drive industry is able to measure the PSA and RSA at the subassembly level at this time, there is no system available that is able to measure PSA/RSA at the …

Intelligibility Of Electrolarynx Speech Using A Novel Hands-Free Actuator, Brian Madden, Mark Nolan, Ted Burke, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx provides quasi-periodic acoustic excitation of the vocal tract. In most electrolarynxes, mechanical vibrations are produced by a linear electromechanical actuator, the armature of which percusses against a metal or plastic plate at a frequency within the range of glottal excitation. In this paper, the intelligibility of speech produced using a novel hands-free actuator is compared to speech produced using a conventional electrolarynx. Two able-bodied speakers (one male, one female) performed a closed response test containing 28 monosyllabic words, once using a conventional electrolarynx and a second time using the novel design. The resulting audio recordings …

High Conductivity Solid Oxide Electrolyte Composite-Laminates Utilizing Scandia/Ceria Co-Doped Zirconia Core With Yttria Stabilized Zirconia Outer Skins, Jay Neutzler, Xinyu Huang, Joshua Sightler, Yan Chen, Nina Orlovskaya

Faculty Publications

Increasing the conductivity of electrolytes in lower temperature Solid Oxide Fuel Cells (SOFC) is of great importance. However, there are several challenges that are to be addressed, which include phase stability of electrolyte’s crystal structure, chemical stability in both oxidizing and reducing environments, and maintaining mechanical integrity and high ionic conductivity over time.

Perspectives On Quality Coordination And Assurance In Global Supply Chains, Ling Li, John N. Warfield

Information Technology & Decision Sciences Faculty Publications

The 2007 recall of Berko Electric Toe-Space Heaters made in the US, the recall of backpack blowers made in Japan, the recalls of toys and pet food produced in China have exposed the potential of global supply chain disruptions. This product recall storm leads to the issue of quality assurance in global supply chain management. Product recalls indicate that manufacturing companies are particularly vulnerable to ensure quality when they source via a global supply chain with poor visibility. Obviously, a supply chain cannot afford this kind of sourcing and supply structure that threatens the supply-chain integrity. This special issue on …

Estimating Industrial Building Energy Savings Using Inverse Simulation, Franc Server, J. Kelly Kissock, Dan Brown, Steve Mulqueen

Mechanical and Aerospace Engineering Faculty Publications

Estimating energy savings from retrofitting existing building systems is traditionally a time intensive process, accomplished by developing a detailed building simulation model, running the model with actual weather data, calibrating the model to actual energy use data, modifying the model to include the proposed changes, then running the base and proposed models with typical weather data to estimate typical energy savings. This paper describes a less time-intensive method of estimating energy savings in industrial buildings using actual monthly energy consumption and weather data. The method begins by developing a multivariate three-parameter changepoint regression model of facility energy use. Next, the …

Analysis And Modeling Of Depth-Of-Cut During End Milling Of Deposited Material, Haythem Gaja

Masters Theses

"This study addresses depth-of-cut detection and tool-workpiece engagement using an acoustic emission monitoring system during milling machining for a deposited material. Online detection of depth-of-cut presents many technical difficulties. Researchers have used various types of sensors and methods to assess the depth-of-cut and surface errors. Due to the strong correlation between acoustic emission and cutting depth during the depth end milling process, it is useful to forecast the depth-of-cut from the acoustic emission signal. This work used regression analysis to model and detect the depth-of-cut. The experiments were carried out on a Fadal vertical 5-Axis computer numerical control machine using …

Development Of Virtual Engineering Simulation For Lean Education, Akalpit Kiran Gadre

Masters Theses

"Global competition and customer demands are pressing modern industry operations to become leaner. The race among the global corporations to "go lean" demands engineers with an in-depth understanding of lean philosophies. An overview of current methods for teaching lean shows that they include small scale hands-on projects, presentations, and guest lectures. There is a need to incorporate a more immersive virtual simulation to further inspire students. Many lean simulation games are available in the market; however, they lack simplicity, ability to store the results, and modeling power.

The goal of this research is to develop a virtual simulation platform, enabling …

Development Of Lower Cost Imaging Systems For Laser Metal Deposition Process, Shyam Barua

Masters Theses

"Laser Metal Deposition (LMD) has been used as an additive manufacturing process in industries such as aerospace and die castings. LMD is especially useful in repair applications involving die repair. However, it is still not used widely in industry due to variations in the quality of parts. There are multiple interactions between various factors which influence the quality of deposit.

There exists a need for defect detection systems to detect any changes in the deposition quality during deposition. On demand detection enables adjustment in process parameters and minimization of rework cost.

Vision systems have been used extensively in the industry …

Innovative Air Breathing Design And Output Control For Portable Proton Exchange Membrane Fuel Cell, Amar Bala Sridhar

Masters Theses

"Proton Exchange Membrane (PEM) Fuel Cell Technology is an energy source that can provide several times more energy per unit volume than current lithium ion batteries that are available in the market today. The barriers that exist that prevent the fuel cell from entering the world of portable applications are mainly system architecture integration. The idea is to have a fully functioning fuel cell with optimum power output using an innovative chimney design. Tests were conducted to quantify the advantage of using a chimney with the fuel cell. Further research was done to shed light on how different chimney designs …

Modeling And Optimization To Evaluate Sustainability Performance Of Customizable Product Service Systems, Ken Harsha Tilakaratne Wijekoon

University of Kentucky Master's Theses

The aim of this thesis is to present a new methodology to evaluate and optimize sustainability of customizable product-service systems while ensuring economic, environmental and societal constraints are also satisfied. Activities across the total product lifecycle are considered to develop a model that evaluates closed-loop flow, while being monitored through the growth, maturity and decline stages of the product to provide a comprehensive analysis. A novel method to evaluate the customer satisfaction is also presented. The research considers a modular product where customization can be achieved by selecting from alternatives while ensuring the compatibility between these alternatives. A manufacturer will …

Mechanical Characterization Of Polymer Electrolyte Membrane With Optical Methods, Xinyu Huang, Luis Alva, Jay Neutzler

Faculty Publications

Mechanical properties of polymer electrolyte membrane have important implications in the endurance of many electrochemical energy conversion devices [1]. Mechanical experiments are effective method to reveal discrete damage developed in the membrane by quantifying the change of mechanical strength and toughness. Regular strain measurement methods are overly intrusive to the thin and relatively fragile polymer electrolyte membrane; hence optical-based minimal invasive stress/strain measurement methods are studied.

A Shock Tube Technique For Blast Wave Simulation And Studies Of Flow Structure Interactions In Shock Tube Blast Experiments, Nicholas N. Kleinschmit

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Improvised explosive devices (IED’s) are widely used against US and allied forces fighting in Iraq and Afghanistan. Exposure to IED blast may cause blast-induced traumatic brain injury (bTBI). The injury mechanisms are however not well understood. A critical need in bTBI-related research is the ability to replicate the loading conditions of IED blast waves in a laboratory environment. In this work, experimental studies have been carried out to explore the use of the shock tube technique for generating air shock waves that mimic the temporal and spatial characteristics of free-field blast waves and to investigate the blast wave-test sample interactions …

Use Of Collaborative Learning Technology To Support Cross-Faculty Group Learning, Colm O'Kane, Jennifer Mcdonnell

Conference Papers

The scope of applications of computer supported collaborative learning (CSCL) has grown exponentially in recent years. This group of techniques has been found to be extremely effective as a collaborative tool to inspire scaffolding between students. It is also useful when several academic supervisors wish to view the same project work.

This paper describes the process and the motivation behind the first implementation of a campus pack-based project in Year 3 of Technological University Dublin's (DIT) BSc. in Product Design programme. Issues have been encountered in previous years with this cross-faculty managed project, but this work shows the potential that …

Self Assembly In Additive Manufacturing: Opportunities And Obstacles, Nathan B. Crane, J. Tuckerman, G. N. Nielson

Faculty Publications

Purpose

Additive manufacturing offers substantial flexibility in shape, but much less flexibility in materials and functionality—particularly at small size scales. A system for automatically incorporating microscale components would enable the fabrication of objects with more functionality. This paper considers the potential of self assembly to serve as an automated programmable integration method. In particular, it addresses the ability of random self assembly processes to successfully assemble objects with high performance despite the possibility of assembly errors.

Methodology

A self-assembled thermoelectric system is taken as a sample system. The performance expectations for these systems are then predicted using modified one-dimensional models …

A Methodology Towards Comprehensive Evaluation Of Shape Memory Alloy Actuators For Prosthetic Finger Design, Kevin O'Toole

Doctoral

Presently, DC motors are the actuator of choice within intelligent upper limb prostheses. However, the weight and dimensions associated with suitable DC motors are not always compatible with the geometric restrictions of a prosthetic hand; reducing available degrees of freedom and ultimately rendering the prosthesis uncomfortable for the end-user. As a result, the search is on-going to find a more appropriate actuation solution that is lightweight, noiseless, strong and cheap. Shape memory alloy (SMA) actuators offer the potential to meet these requirements. To date, no viable upper limb prosthesis using SMA actuators has been developed. The primary reasons lie in …

Asme Human Powered Vehicle, Benjamin Knaus, Philip Basmadjian, Nick Supat

Mechanical Engineering

Speed Solutions has been contracted to design and build a Human Powered Vehicle (HPV) frame and drivetrain for the Cal Poly HPV club to use in their 2011 race season. This project is being funded by the Cal Poly HPV club and their sponsors. The goal is to design, test and build a bicycle frame that the HPV club can attach to a fairing of their design. Primary design considerations will include speed, weight, cost, rider ergonomics, reliability and ease of repair. This vehicle will be used to compete in ASME’s Human Powered Vehicle Challenge (HPVC) series of races.

Adapted Recumbent Bike, Kurtis Mundell, Dane Tiemeier, Laura Yakuma, Darius Yu

Mechanical Engineering

The adapted recumbent project was to redesign a disabled veteran’s recumbent bicycle.  The main areas of concern were the crank pedal, chain tension, braking and steering system, and ergonomics. Since the customer is an avid biker, this bike will be used often, so the design is based on the ease of repair and replacement.  The crank system was redesigned to a lightweight, adjustable part with chain clearance and high strength. The chain tension was improved by replacing the existing single idler wheel/chain tube system with a dual idler wheel system. The dual idler has a titanium sprocket in one of …

Piedras Blancas Clock Works, Andrew James, Andrew Jupin, Matt Weber

Mechanical Engineering

In 1875, the Piedras Blancas Lighthouse was built to warn ships sailing the California coast of the hazards of the rocky shore. In 1949 a fierce storm damaged the top portion of the lighthouse and the eight ton cast iron and brass assembly had to be replaced by a much lighter piece that still served the purpose of warning oncoming vessels. The former top portion came to rest in downtown Cambria and is still there today, enclosed in a glass room to be observed by visitors and townspeople. Today, the Piedras Blancas Light station is cared for by the Bureau …

An Analysis Of The Manufacturing Process As Related To The Camber Requirement For Brake Pads, Daniel Patrick Midden

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Daniel Patrick Midden on November 30, 2010.

Lean Manufacturing As A Source Of Competitive Advantage, Ryan Scott Williams

Theses and Dissertations

The productivity advances generated from lean manufacturing are self-evident. Plants that adopt lean are more capable of achieving high levels of quality, shorter lead times, and less waste in the system. While it seems logical that higher levels of productivity and quality, as is common in lean companies, should result in positive financial performance, the research community has failed to establish the financial profitability of lean. Those researchers who have studied the financial returns issue report varying results. The goal of this research was to determine if a connection exists between lean and financial success and to discover why so …

Lunar Wormbot--A Robotic Tunneling Worm For Operation In Harsh Environments, Josh Johnson

Von Braun Symposium Student Posters

No abstract provided.

Sae Baja: Final Drive Gearbox, Michael Mccausland, Michael Watkins, Ian Masterson, Andrew Sommer

Mechanical Engineering

This paper presents the results of a manual transmission project for SAE Baja. A full engineering process is documented, including problem definition, scheduling, conceptualization, decision theory, synthesis, analysis, manufacturing, and testing. A comparison is made between existing and potential mechanical power train solutions. The final design is analyzed in dynamic simulations, AGMA stress, predicted FFT spectrums, and shifting rod buckling. A number of complicated parts are manufactured through investment casting and direct CNC machining. Issues in the final assembly have prevented the project from being fully realized, recommendations are made for future SAE Baja teams.

Computer Aided Contour Profiling Of High Strength Deposits, Sriram Praneeth Isanaka, Amar Bala Sridhar, Frank W. Liou, Joseph William Newkirk

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Additive manufacturing processes suffer from the effect of ripples, edge rounding and surface variations. To reduce their effect, ideal process parameters for the laser deposition process were investigated. Also, a new method was identified to analyze deposits by accurately plotting their contours. This was achieved through point cloud data of the deposits generated using coordinate measurement and 3D scanning. Curve fitting was performed on the data in Matlab to generate the contours of the deposit. The intercept values, heights, and contact angle of the curves give an indication of the uniformity of deposits and aid in reducing defects.

Freeze Extrusion Fabrication Of 13-93 Bioactive Glass Scaffolds For Bone Repair, Tieshu Huang, Nikhil D. Doiphode, M. N. Rahaman, Ming-Chuan Leu, B. Sonny Bal, D. E. Day

Materials Science and Engineering Faculty Research & Creative Works

There is an increasing demand for synthetic scaffolds with the requisite biocompatibility, internal architecture, and mechanical properties for the bone repair and regeneration. In this work, scaffolds of a silicate bioactive glass (13-93) were prepared by a freeze extrusion fabrication (FEF) method and evaluated in vitro for potential applications in bone repair and regeneration. The process parameters for FEF production of scaffolds with the requisite microstructural characteristics, as well as the mechanical and cell culture response of the scaffolds were evaluated. After binder burnout and sintering (60 min at 700°C), the scaffolds consisted of a dense glass network with interpenetrating …

Selective Laser Sintering Of 13-93 Bioactive Glass, Krishna C. R. Kolan, Ming-Chuan Leu, Greg Hilmas, Mariano Garcia Velez

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Bioactive glasses are more promising than biopolymers in fabricating scaffolds for bone tissue repair because they convert to hydroxyapatite, when implanted in vivo. Both direct and indirect selective laser sintering (SLS) methods of 13-93 bioactive glass were considered in this research to study the feasibility of fabricating scaffolds for bone repair applications. Stearic acid was used as the binder in the indirect method to fabricate the scaffolds. The green scaffolds underwent binder burnout and sintering at various soaking conditions between 675⁰C and 700⁰C, achieving a maximum compressive strength of 23.6 MPa, which is higher than that of the human cancellous …

Laser Based Rapid Manufacturing Of Metallic Gas Diffusion Layers For Pem Fuel Cells, Gargi Tandra, Todd E. Sparks, Shyam Barua, Nikhil P. Kulkarni, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Gas Diffusion layers (GDL’s) are an essential component of Polymer Electrolyte Membrane Fuel cells (PEMFC’s) which aid in thermal & electrical conductivities, water management and act as backup layers for the membrane electrode assemblies. This paper summarizes the effort to prototype metallic GDL designs using a miniature laser deposition system developed at Missouri University of Science & Technology. The pore sizes are controlled by masking the diverging laser beam using stainless steel masks of varying sizes and shapes. The through pore feature and further treatment of the GDL’s for hydrophobicity reduces the water management issue and thereby increases the performance …

Mea Manufacturing Using An Additive Manufacturing Process To Deposit A Catalyst Pattern In An Mea And Its Impact On Cost Reduction, Nikhil P. Kulkarni, Todd E. Sparks, Gargi Tandra, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The manufacturing of a fuel cell Membrane Electrode Assembly (MEA) is a significant cost driver in polymer-electrolyte membrane (PEM) fuel cell technologies, primarily due to the inclusion of expensive materials in the catalyst layer. The selective deposition of a catalyst on the MEA of a fuel cell can drastically reduce the costs depending upon the catalyst, method used for deposition, and production volume. In this paper, testing and analysis of a novel catalyst iridium oxide is discussed. The performance of the catalyst will be compared with the conventional catalysts which will give us an estimate of its effectiveness however, in …

Multi-Axis Planning System (Maps) For Hybrid Laser Metal Deposition Processes, Frank W. Liou, Jianzhong Ruan, Todd E. Sparks

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper summarizes the research and development of a Multi-Axis Planning System (MAPS) for hybrid laser metal deposition processes. The project goal is to enable the current direct metal deposition systems to fully control and utilize multi-axis capability to make complex parts. MAPS allows fully automated process planning for multi-axis layered manufacturing to control direct metal deposition machines for automated fabrication. Such a capability will lead to dramatic reductions in lead time and manufacturing costs for high-value, low-volume components with high performance material. The overall approach, slicing algorithm, machine simulation for planning validation, and the planning results will be presented.

Optimization Of Selective Laser Sintering Process For Fabrication Of Zirconium Diboride Parts, Ming-Chuan Leu, Shashwatashish Pattnaik, Greg Hilmas

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Selective Laser Sintering (SLS) was investigated to fabricate Zirconium Diboride (ZrB₂) parts for ultra-high temperature applications. Experiments were conducted to determine values of SLS process parameters (laser power, scan speed, line spacing, and layer thickness) that can be used to build ZrB₂ parts with high integrity and sharp geometrical features. A sacrificial plate with a proper number of layers (determined from experimentation) separated from the main part was built in order to reduce thermal gradients when building the main part. The sacrificial plate was found to assist in eliminating cracks in the bottom of the main part. …