Mechanical Engineering Commons^™

A Mathematical Model For Quantifying System Evolvability Using Excess And Modularity, Morgan Wesley Parry Tackett

Theses and Dissertations

An important factor in system longevity is service-phase evolvability, which is defined as the ability of a system to physically transform from one configuration to a more desirable configuration while in service. These transformations may or may not be known during the design process, and may or may not be reversible. A study of 210 engineered systems was performed and found that system excess and modularity allow a system to evolve while in service. Building on these observations, this thesis introduces mathematical relationships that map a system's excess and modularity to that system's ability to evolve. These relationships are derived …

Using Topology Optimization To Numerically Improve Barriers To Reverse Engineering, Devin Donald Lebaron

Theses and Dissertations

Here explored is a method by which designers can use the tool of topology optimization to numerically improve barriers to reverse engineering. Recently developed metrics, which characterize the time (T) to reverse engineer a product, enable this optimization. A key parameter use din the calculation of T is information content (K). The method presented in this thesis pursues traditional topology optimization objectives while simultaneously maximizing K, and thus T, in the resulting topology. This thesis presents new algorithms to 1) evaluate K for any topology, 2)increase K for a topology by manipulating macro-scale geometry and micro-scale crystallographic information for each …

Micro-Jet Cooling Of Cutting Tools, Douglas J. Woodruff, Gary W. Pannala, William J. Endres, Nicole Barna, Quincy Schultz, David Thomasini, Matthew Zblewski

Michigan Tech Patents

A cutting tool includes an insert defining a flank face, a rake face, and a cutting edge between the flank face and rake face. The cutting tool includes micro-nozzles formed in at least one of the tool body and the insert, and aimed at the cutting edge. Each micro-nozzle generates a micro jet of cutting fluid in close proximity to the cutting edge and adjacent to at least one of the flank face and the rake face.

Floating Electrode Electrowetting On Hydrophobic Dielectric With An Sio2 Layer, Mehdi Khodayari, Benjamin Hahne, Nathan B. Crane, Alex A. Volinsky

Faculty Publications

Floating electrode electrowetting is caused by dc voltage applied to a liquid droplet on the Cytop surface, without electrical connection to the substrate. The effect is caused by the charge separation in the floating electrode. A highly-resistive thermally-grown SiO2 layer underneath the Cytop enables the droplet to hold charges without leakage, which is the key contribution. Electrowetting with an SiO2 layer shows a memory effect, where the wetting angle stays the same after the auxiliary electrode is removed from the droplet in both conventional and floating electrode electrowetting. Floating electrode electrowetting provides an alternative configuration for developing advanced electrowetting-based devices.

An Exploration Of Carbon-Filled Carbon Nanotubes As A Potential Material In Coronary Stents, Kristopher Neil Jones

Theses and Dissertations

The purpose of this research is to explore the potential of using carbon-infiltrated carbon nanotubes (CI-CNT) as a material for coronary artery stents. Stents are commonly fabricated from metal, which may not perform as well as many polymers and ceramics in biomedical applications. Pyrolytic carbon, a ceramic, is currently used in medical implant devices due to its preferrable biocompatibility properties. Micro-patterned pyrolytic carbon devices can be created by growing carbon nanotubes, and then filling the space between with amorphous carbon via chemical vapor deposition. We prepared multiple samples of two different planar stent-like flexible geometries and smaller cubic structures out …

Heterogeneous Relaxation Dynamics In Amorphous Materials Under Cyclic Loading, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

Molecular dynamics simulations are performed to investigate heterogeneous dynamics in amorphous glassy materials under oscillatory shear strain. We consider three-dimensional binary Lennard-Jones mixture well below the glass transition temperature. The structural relaxation and dynamical heterogeneity are quantified by means of the self-overlap order parameter and the dynamic susceptibility. We found that at sufficiently small strain amplitudes, the mean square displacement exhibits a broad subdiffusive plateau and the system undergoes nearly reversible deformation over about 104 cycles. Upon increasing strain amplitude, the transition to the diffusive regime occurs at shorter time intervals and the relaxation process involves intermittent bursts of large …

College Of Engineering Senior Design Competition Spring 2013, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Senior Design Experience

Part of every UNLV engineering student's academic experience, the Senior Design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs and prototypes a product in this required element of the curriculum. Working in teams, the senior design project encourages students to use everything learned in the engineering and computer design programs to create a practical, real world solution to an engineering challenge.

Beyond the classroom ...

Because of the requirement to work in teams, students also build good communication skills, presentation skills and even business writing skills. They also have to …

Monte Carlo Uncertainty Analysis For Photothermal Radiometry Measurements Using A Curve Fit Process, Kyle Horne, Austin Fleming, Heng Ban

Utah Space Grant Consortium

Photothermal Radiometry (PTR) has become a popular method to measure thermal properties of layered materials. Much research has been done to determine the capabilities of PTR, but with little uncertainty analysis. This study performs a Monte Carlo uncertainty analysis to quantify uncertainty of film diffusivity and effusivity measurements, presents a sensitivity study for each input parameter, compares linear and logarithmic spacing of data points on frequency scans, and investigates the validity of a 1-D heat transfer assumption.

Determining Appropriate Heating And Cooling Thermostat Set Points For Building Energy Simulations For Residential Buildings In North America, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Existing building energy simulation tools have a purported tendency to over-predict heating use and, in some cases, to under-predict cooling use, an outcome often attributed to inappropriate assumptions about thermostat management. As a result, a systematic review was conducted for the purposes of determining typical heating and cooling set points for single-family houses in North America. The preliminary consensus results provide an empirical basis for establishing typical inputs for building energy simulation models, increasing prediction accuracy of heating and cooling loads. The results of this review have been applied as default values in the Lawrence Berkeley National Laboratory's Home Energy …

Assessment Of An Automotive Driving Simulator To Educate Novice Drivers, John Wagner, Qimin Yao, Kim Alexander, Philip Pidgeon

Publications

Novice drivers are more likely to be involved in vehicle crashes than more experienced drivers. Transportation system simulators, such as aerospace, automotive, and rail, have been used effectively over several decades in support of operator training and research studies. The immersive high-end automotive simulators tend to be large-scale, difficult to move, and relatively cost ineffective for widespread deployment. In contrast, a mobile vehicle training system often features simplistic environments which are not readily accepted by teenagers who evaluate the driving experience as compared to commercial video games. Consequently, a need exists for a low-cost portable automotive training system that provides …

Identification Of And Effects On The Depth Of The Machining Affected Zone In Nickel-Based Superalloys, Boyce Richardson

All Theses

The formation of subsurface damage during machining of nickel-based superalloys is a critical quality concern for the manufacture of gas turbine components. The identification and understanding of this zone are critical to the reduction of destructive testing and scrap costs in an ever changing manufacturing environment. This thesis seeks to provide a novel objective method for identification of the depth of this zone and an empirical model for the effects of machining parameters on this zone. This allows for optimal machining parameters to be used in manufacturing reducing the need for destructive testing, while also reducing manufacturing costs by reducing …

Focused Novice Driver Program - Assessment Results And Discussion, John Wagner, Lance Clark, Kim Alexander, Philip Pidgeon, Ken Rogich

Publications

Skills and experiences of novice drivers do not favorably compare to motorists with significantly greater driving time and life experiences. Recent developments in driver education and training have focused on multistage instruction to take advantage of the time delay for driving privileges in Graduated Driver Licensing (GDL) systems as a means to provide additional instruction. A supplemental safe driving program tailored to address the risky behaviors of novice drivers has been developed by Clemson University Automotive Safety Research Institute (CU-ASRI) and the Richard Petty Driving Experience (RPDE). The program offers training in anticipatory safe driving strategies based on the leading …

Decision Support Systems For Assembly Line Planning -Modular Subsytems For A Large Scale Production Management System, Rahul Renu

All Theses

In the domain of assembly lines, process sheets are entities that carry assembly process descriptions (work instructions), assembly time estimations, product workspaces and other configuration management and control information. These process sheets get assigned to workstations during the process of assembly line balancing. In this research two tools have been developed to aid in the assembly line planning process. In order to ensure that assembly line workers do not intrude upon each other's workspace, two assembly processes operating on the same product workspace must not be assigned to the same station. Generating and maintaining product workspace information for every process …

Helicopter Toy And Lift Estimation, Said Shakerin

All Faculty Articles - School of Engineering and Computer Science

A $1 plastic helicopter toy (called a Wacky Whirler) can be used to demonstrate lift. Students can make basic measurements of the toy, use reasonable assumptions and, with the lift formula, estimate the lift, and verify that it is sufficient to overcome the toy's weight.

Analysis And Mitigation Of The Cubesat Dynamic Environment, Steve M. Furger

Master's Theses

A vibration model was developed for CubeSats inside the Poly-Picosatellite Orbital Deployer (P-POD). CubeSats are fixed in the Z axis of deployers, and therefore resonate with deployer peaks. CubeSats generally start fixed in the X and Y axes, and then settle into an isolated position. CubeSats do not resonate with deployers after settling into an isolated position. Experimental data shows that the P-POD amplifies vibration loads when CubeSats are fixed in the deployer, and vibration loads are reduced when the CubeSats settle into an isolated position. A concept for a future deployer was proposed that isolates CubeSats from the deployer …

Stability Control Of Triple Trailer Vehicles, Michael O'Neal Arant

All Dissertations

While vehicle stability control is a well-established technology in the passenger car realm, it is still an area of active research for commercial vehicles as indicated by the recent notice of proposed rulemaking on commercial vehicle stability by the National Highway Traffic Safety Administration (NHTSA, 2012). The reasons that commercial vehicle electronic stability control (ESC) development has lagged passenger vehicle ESC include the fact that the industry is generally slow to adopt new technologies and that commercial vehicles are far more complex requiring adaptation of existing technology. From the controller theory perspective, current commercial vehicle stability systems are generally passenger …

A Model-Free Approach To Vehicle Stability Control, Chinmay Pandit

All Theses

This project explored the feasibility of using measured responses of a passenger car together with a fuzzy logic based control algorithm to sense the onset of under-steer (or loss of steering control) and mitigate or eliminate it. The controller is simple and robust and, unlike existing controllers, instead of comparing the vehicle response to that of an idealized model it makes decisions based solely upon the measured response of the car.
Simulations were conducted (using CarSim) of various vehicles executing the skid pad and the double lane change tests to characterize the vehicle behavior. Consistent and qualitatively similar patterns in …

A Preliminary Discourse On Adhesion Of Nanofibers Derived From Electrospun Polymers, Pei Chen

Mechanical Engineering Faculty Research

To bio-mimic gecko’s foot hair, which possess high adhesion strength and can be re- usable for lifetime, fibrous membranes are fabricated by electrospinning to provide sufficient adhesion energy. Shaft-loaded blister test (SLBT) is firstly used to measure the work of adhesion between electrospun membrane and rigid substrate. Poly(vinylidene fluoride) (PVDF) were electrospun with an average fiber diameter of 333±59 nm. Commercial cardboard with inorganic coating was used to provide a model substrate for adhesion tests. In SLBT, the elastic response PVDF was analyzed and its adhesion energy measured. FEA model with cohesive layer is developed to evaluate the experiment results. …

End-Of-Life Management Of Crystalline Silicon Photovoltaic Module, Jun-Ki Choi

Mechanical and Aerospace Engineering Faculty Publications

PV manufacturing has been growing over the past 10 years and further annual growth of 15% is expected until 2020. A study on positioning a grand plan for solar power shows how vast PV arrays and other renewable energies can provide significant amount of electricity and total energy needs by 2050. Various new PV technologies have been introduced in the market and existing technologies have undergone further development. How all these developments will affect the fate of the end-of-life PV modules is uncertain. In addition, the market price of some rare earth materials utilized in the manufacturing of the various …

Magnetic Manipulation Of Particles And Cells In Ferrofluid Flow Through Straight Microchannels Using Two Magnets, Jian Zeng

All Theses

Microfluidic devices have been increasingly used in the past two decades for particle and cell manipulations in many chemical and biomedical applications. A variety of force fields have been demonstrated to control particle and cell transport in these devices including electric, magnetic, acoustic, and optical forces etc. Among these particle handling techniques, the magnetic approach provides clear advantages over others such as low cost, noninvasive, and free of fluid heating issues. However, the current knowledge of magnetic control of particle transport is still very limited, especially lacking is the handling of diamagnetic particle. This thesis is focused on the magnetic …

A Computed Tomography-Based Model Of The Infant Hip Anatomy For Dynamic Finite Element Analysis Of Hip Dysplasia Biomechanics, Kyle Snethen

HIM 1990-2015

Newborns diagnosed with hip dysplasia face severe consequences when treatments fail. The Pavlik harness presents the most common worldwide treatment for correcting this medical hip abnormality in newborns, but becomes increasingly ineffective as subluxation increases. A dynamic finite element analysis on the hip joint would yield results that could provide insight to physicians as to how the Pavlik harness could be optimized to increase its success rate and develop patient-specific treatment plans. The study completes the first step in such an analysis by generating a three-dimensional model of an infant hip joint directly derived from computed tomography imaging in order …

Production, Control And Actuation Of Micron-Sized Particles In A Microfluidic T-Junction, James Wilson

HIM 1990-2015

This research is directed towards understanding the mechanisms associated with the manufacture of solid microspheres less than 100 [micrometers], from liquid droplets with nanosuspensions in a microfluidic T-junction, which are heated downstream of the channel. Preliminary material characterization tests on colloidal suspensions of alumina and copper oxide demonstrate promising temperature dependent viscosity results indicating solidification in the temperature range of 40°C-50°C. The solidification mechanism is referred to as Temperature Induced Forming and is described by polymeric bridges formed between nanoparticles in suspension at elevated temperatures, resulting in a solid structure. The polymer network results from the ionization of alumina at …

Simulation Of Vawt And Hydrokinetic Turbines With Variable Pitch Foils, Lindsay Damon Woods

Boise State University Theses and Dissertations

A dynamic computer model of a turbine was developed in MATLAB in order to study the behavior of vertical axis wind and hydrokinetic turbines with articulating foils. The simulation results corroborated the findings of several empirical studies on various turbines in both wind and water currents. The model was used to analyze theories of pitch articulation and to inform the discussion on turbine design. Several new patents and proposed configurations were tested. Simulation results showed that pitch articulation allowed Darrieus-style vertical axis wind turbines to start from rest. The tip speed ratio was found to increase rapidly, carrying the turbine …

The Design, Fabrication, And Pressure Testing Of A Low-Temperature Co-Fired Ceramic Electric Propulsion Thruster, Derek J. Reis

Boise State University Theses and Dissertations

Electric thrusters have been used for many years for orbital station-keeping and propulsion. As technology advances, smaller satellites are possible that require less thrust. The resulting miniature electric thrusters need low-weight and compact designs. This thesis specifies the design, fabrication, and testing of a thruster and its fluid delivery system designed for use with a micro-satellite weighing less than fifty kilograms.

The advent of Micro-Electro-Mechanical Systems (MEMS) has sparked a new market with incredibly small scale designs. Using this technology with Low-Temperature Co-fired Ceramic (LTCC) materials has spawned the new distinction of Ceramic Micro-Electro-Mechanical Systems (C-MEMS). The thruster body is …

Development Of A Pdms Based Micro Total Analysis System For Rapid Biomolecule Detection, Balaji Srinivasan Venkatesh

Graduate Theses and Dissertations

The emerging field of micro total analysis system powered by microfluidics is expected to revolutionize miniaturization and automation for point-of-care-testing systems which require quick, efficient and reproducible results. In the present study, a PDMS based micro total analysis system has been developed for rapid, multi-purpose, impedance based detection of biomolecules. The major components of the micro total analysis system include a micropump, micromixer, magnetic separator and interdigitated electrodes for impedance detection. Three designs of pneumatically actuated PDMS based micropumps were fabricated and tested. Based on the performance test results, one of the micropumps was selected for integration. The experimental results …

Design And Fundamental Understanding Of Minimum Quantity Lubrication (Mql) Assisted Grinding Using Advanced Nanolubricants, Parash Kalita

Graduate Theses and Dissertations

Abrasive grinding is widely used across manufacturing industry for finishing parts and components requiring smooth superficial textures and precise dimensional tolerances and accuracy. Unlike any other machining operations, the complex thermo-mechanical processes during grinding produce excessive friction-induced energy consumption, heat, and intense contact seizures. Lubrication and cooling from grinding fluids is crucial in minimizing the deleterious effects of friction and heat to maximize the output part quality and process efficiency. The conventional flood grinding approach of an uneconomical application of large quantities of chemically active fluids has been found ineffective to provide sufficient lubrication and produces waste streams and pollutants …

Optimization Of Automated Temperature Measurement System For Formed Meat Products, Tyler Norman

Mechanical Engineering Undergraduate Honors Theses

The Federal Safety and Inspection Services in accordance with United States Department of Agriculture require that formed meat products be cooked to a specified minimum internal temperature in order to eliminate the possible presence of harmful bacteria. The current system of verifying the internal temperatures of formed meat products consists of manually inserting a temperature probe into the selected sample as it exits the oven. Creating an automated system that measures and records the internal temperatures of formed meat samples as they exit the oven along a meat processing line has been the topic of an ongoing research. The most …

Design And Construction Of An Experiment For The Investigation Of The Effects Of Gust On Flapping Wing Micro Air Vehicle Power Consumption, Brett Hiller

Mechanical Engineering Undergraduate Honors Theses

In recent years, the promising nature of flapping wing flight has led researchers to investigate the wing morphology and unsteady wing aerodynamics found in insects to aid in the design of modern micro air vehicles (MAVs). A high-fidelity flapping wing MAV could achieve high mobility, hovering stability, increased stealth, and efficient flight at low speeds. These characteristics offer a viable solution to the operational requirements for the typical hazardous and dynamic environments encountered during flight. While the kinematics and morphology of flapping wings are well-understood, significant research has yet to be completed with respect to the control and power requirements …

Exploration Into Properties Of Molybdenum Disulfide Using Atomistic Simulation, Joseph Simpson

Mechanical Engineering Undergraduate Honors Theses

Molybdenum disulfide (MoS2) has a lamellar crystal structure, which makes it ideal for use as a solid lubricant. Transmission electron microscope (TEM) images have shown that line defects exist within the lattice of mechanically deformed MoS2, but the physical mechanisms which lead to the formation of these defects are unknown. The two central objectives of this research are to use molecular dynamics simulations to study the effects of tensile deformation on both single layer and bulk MoS2 and explore the properties of line defects in an otherwise perfect lattice of MoS2. Under tensile loading, molecular dynamics simulations show a multi-stage …

Transformable Wheelchair, Benjamin Shurtz

Undergraduate Honors Capstone Projects

This report includes the development, design, and analysis of a transformable wheelchair. There was a need to design and build a wheelchair that transformed to be pushed, pulled, or self-propelled. This design meets the need of physically restricted wheelchair users who frequent simple hiking trails without needing to move to a secondary off-road capable device. Documentation for concepts, analysis, and completed design details follows.