Mechanical Engineering Commons^™

Mems 411 Design Report Group O: Naked Mole Rat Trap, Drew Pikey, Adam Glassl, Sam Nadell

Mechanical Engineering Design Project Class

Naked mole-rats are mouse size rodents that live in underground colonies in East Africa. They are best known for having a queen and workers like bees. Prof Stan Braude has been studying them in Kenya and Ethiopia for over 25 years and has trapped over 10,000 of these animals, marked and released them. He is the world’s expert at trapping naked mole-rats and yet, he still needs a better trap. Prof. Stan Braude is looking forward to working with a team of real engineers and designers who can help him complete this project.

Automatic Onion Peeler, William R. Luer, Matthew O. Clohisy, Craig A. Claire, Dylan L. Newcomb

Mechanical Engineering Design Project Class

Our senior design report encompasses the design selection, process, and fabrication of an automatic onion peeler. Our design is intended for the peeling of medium yellow onions in restaurant-scale applications. Our machine is easily cleaned and can be safely operated by one person.

Autonomous Shopping Cart, John Gutsch, Steven Taschner, Asim Zaidi

Mechanical Engineering Design Project Class

In shopping centers across the United States, customers must return shopping carts after they used them by themselves. For a variety of reasons, a significant number of shopping carts are left in parking lots after being used. This results in expenses to the store in the form of damaged carts, man hours required to return each one, and law suits from customers whose cars are damaged by free carts. This project is an add-on mechanism by which allows shopping carts to return to the shopping center autonomously. The cart should be able to locate a preset track that is set …

Universal Pitter, Angelica Price, Rachel Venn

Mechanical Engineering Design Project Class

Fruits with pits in them have been cumbersome to eat due to the delicate quality of the fruit and the rigid structure of the pits that must be removed. Many types of pitters already exist, but any are for small pits such as cherries and olives or involve to much manual action. This pitter will remove the pit out of multiple types of fruit while holding the fruit in a manner that does not damage the fruit. This projected was initiated by Rachel Venn, an engineering student at Washington University in St. Louis, who took a pole amongst family and …

Building A Better Naked-Mole Rat Trap Mems 411- Senior Design Course, Alex Flammond, Lance Middleton, Andrew Chang

Mechanical Engineering Design Project Class

In this paper, we design, analyze, test, and construct an improved naked mole rat trap for Prof. Stan Braude of Washington University in St. Louis.

Maneuverable Backpack Scooter Attachment, Andrew Goldfield, Alex Roesch, Cosmo Centanni, Nina Nepa

Mechanical Engineering Design Project Class

A mechanical device that will aid in the collaboration between a scooter and a backpack. Due to the weight of typical backpack, our device will aid the consumer to carry less weight on their backs, and create a device to fold into the scooter so that it nicely fits in a classroom setting. This device will be detachable so that the scooter can be operated without the attachment.

Mechanically Advantageous Wheelchair, Katy Hagerty, Noah Dromgoole, Carlo Balleria, Andrew Orona

Mechanical Engineering Design Project Class

This project will utilize a gear system to create a multispeed wheelchair. Multiple gears will allow users to adjust the speed of the wheelchair for appropriate scenarios. Our device will be modular and use a different gear mechanism than products currently in the marketplace.

Telescoping Cup Holder, Richard Kristian O. Pajarillo, Eric Nehrbas, Charlie Morrow

Mechanical Engineering Design Project Class

Cup holders are a beloved feature of the modern automobile because they keep your drink stable and close, ensuring that minimal work is needed to grab it. Our mission is to provide a cup holder for everyday use outside of vehicles. Our device will hold drinks of most sizes, and will keep them cool. Motion activation will raise the drink to a convenient height using a telescoping motion, and then lower to a sturdy position that is out of the way. The finished product will minimize the amount of work required to retrieve the drink, and grab some attention as …

Group H: Expandable Brush, Aaron Hall, Michael Roznik

Mechanical Engineering Design Project Class

This is an overview of our project to design an expandable brush. This brush is designed to be versatile and able to clean a variety of vessels with narrow necks, wide bases, and complex geometries. Our prototype consisted of two parts: an outer sleeve with a deflector and a handle with a head piece to hold our bristle filaments. This design allows the user to insert the brush into a vessel and then control how far outward the bristles expand for easy cleaning.

Group F: Cell Phone Forearm Holder, Jacob Aley, Emily Groth, Sinclair Hodge

Mechanical Engineering Design Project Class

Design a forearm device that stores cell phones while traveling and provides an easy access apparatus for one handed use on the go. A compression sleeve will be the main feature as it will be the way in which our device will stay on the users arm. An adjustable apparatus that securely holsters the cellphone will be another feature so that our device will be viable for cellphones of varying dimensions. A swivel apparatus that will allow users to select horizontal or vertical viewing of the cellphone while connected to our device. A track system that allows for the movement …

Compact Furniture Dolly, Gary Hu, Jieun Yim, Jason Xie, Jiayi Hou

Mechanical Engineering Design Project Class

One problem faced by people during moving is how to move large pieces of furniture, i.e. sofa, mattress, table, refrigerator, etc., conveniently without damaging them. A typical small dolly is incapable of carrying such large pieces, and a bulky dolly is inappropriate for an indoor use because it can damage the furniture and the floor. Besides, in either case, the user should lift up and put the load on the dolly. People who want to change positions of their furniture regularly to get a fresh look for the house, it is cumbersome to call a moving company every time. Our …

Sanitation System For Underdeveloped Countries, Anish Agrawal, Mutian Tang, Dylan Lesher, Reid Schur

Mechanical Engineering Design Project Class

Currently, there are over 2.5 billion people living in the world without having access to proper sanitation. This is primarily because of lack of access to water and/or their financial situation to afford a sanitation system. Therefore, there is a need for a sanitation system which can flush in less water and is inexpensive. This project involves the creation of a sanitation system for use in impoverished areas with little access to water or electricity.

On Phase Change Material Heat Exchangers: A Computational And Experimental Investigation, Christian Omar Rodriguez Dieppa

Theses and Dissertations

The emergence of ground- and airborne-based high energy laser (HEL) weapon systems has created a need for high-rate thermal energy storage (TES) devices that meet demanding size, weight, and power (SWaP) requirements for integration into the HEL thermal management system (TMS). Current and near-term HEL weapon systems produce thermal loads on the order of 30-300 kW when emitting, and approximately 5-10% of the peak load when in a non-emitting standby state. Emission to standby duty cycles of 10-50% are common, and therefore, sizing the TMS for real-time rejection of the peak thermal load is not practical. Accordingly, TES components can …

Development Of A Dsm-Based Model For Managing The Design Of Complex Systems Considering The Impact Of Technological Obsolescence, Gershom Kwaku Obeng

Mechanical & Aerospace Engineering Theses & Dissertations

Obsolescence has been a constant issue for process planners and designers and if not properly accounted for, obsolescence can become an expensive issue. As systems become more complex, interconnected, and nonhomogeneous, separate studies of single groups of equipment are no longer sufficient in modeling the obsolescence of the systems that they make up. The purpose of this dissertation is to model the likelihood of a process's design becoming obsolescent given the obsolescent behavior of the equipment used to complete the process. The methodology discussed in this work is based on a combination of using a systems engineering tool called the …

An Examination Of The Indentation Size Effect In Fcc Metals And Alloys From A Kinetics Based Perspective Using Nanoindentation, David Earl Stegall

Mechanical & Aerospace Engineering Theses & Dissertations

The indentation size effect (ISE) in metals is described as the rise in hardness with decreasing depth of indentation and contradicts conventional plasticity behavior. The goal of this dissertation is to further examine the fundamental dislocation mechanisms that may be contributing to the so-called indentation size effect. In this work, we examined several metals and alloys including 99.999% Aluminum (SFE ~200 mJ/m²), 99.95% Nickel (SFE ~125 mJ/m²), 99.95% Silver (SFE ~22 mJ/m²⁾, and three alloys, alpha brass 70/30 (SFE >10 mJ/m²), 70/30 nickel copper (SFE ~100 mJ/ …

Thermal Analysis Of Continuous And Patterned Multilayer Films In The Presence Of A Nanoscale Hot Spot, Jia-Yang Juang, Jinglin Zheng

Department of Mechanical and Materials Engineering: Faculty Publications

Thermal responses of multilayer films play essential roles in state-of-the-art electronic systems, such as photo/micro-electronic devices, data storage systems, and silicon-on-insulator transistors. In this paper, we focus on the thermal aspects of multilayer films in the presence of a nanoscale hot spot induced by near field laser heating. The problem is set up in the scenario of heat assisted magnetic recording (HAMR), the next-generation technology to overcome the data storage density limit imposed by superparamagnetism. We characterized thermal responses of both continuous and patterned multilayer media films using transient thermal modeling. We observed that material configurations, in particular, the thermal …

A Comparison Of Specularly Reflective Boundary Conditions And Rotationally Invariant Formulations For Discrete Ordinate Methods In Axisymmetric Geometries, Jian Cai, Somesh Roy, Michael F. Modest

Mechanical Engineering Faculty Research and Publications

In simulations of periodic or symmetric geometries, computational domains are reduced by imaginary boundaries that exploit the symmetry conditions. Two boundary conditions are proposed for Discrete Ordinate Methods to solve axisymmetric radiation problems. Firstly, a specularly reflective boundary condition similar to that is used in Photon Monte Carlo methods is developed for Discrete Ordinate Methods. Secondly, the rotational invariant formulation is revisited for axisymmetric wedge geometries. Correspondingly, a new rotationally invariant boundary condition specially designed for axisymmetric problems on wedge shape is proposed to enforce the rotational invariance properties possessed by the radiative transfer equation (RTE) but violated by three-dimensional …

Design And Analysis Of The Impact Diffusion Helmet Through A Finite Element Analysis Approach, Steven Paul Warnert

Master's Theses

By applying the finite element approach to the design and analysis of the impact diffusion helmet, many helmet configurations were able to be analyzed. Initially it was important to determine what design variables had an influence on the impact reducing abilities of the helmet design. The helmet was run through a series of Abaqus simulations that determined that a design with two oval shaped channels running along the length of the helmet was best. Next, these options were optimized to generate the helmet that produced the greatest impact reduction. The optimization simulations determined that a helmet that pushed the channels …

Analysis Of Fatigue Crack Propagation In Welded Steels, Roberto Angelo Demarte

Master's Theses (2009 -)

This thesis presents the study of fatigue crack propagation in a low carbon steel (ASTM A36) and two different weld metals (AWS A5.18 and AWS A5.28). Fatigue crack propagation data for each weld wire is of interest because of its use for predicting and analyzing service failures. Fatigue crack growth test specimens were developed and fabricated for the low carbon steel base metal and for each weld wire. Weld specimens were stress relieved prior to fatigue testing. Specimens were tested on a closed-loop servo hydraulic test machine at two different load ratios. Fatigue test data was collected to characterize both …

Parametric Investigation Of A Laboratory Drop Test To Simulate Base Acceleration Induced By Wave Impacts Of High Speed Planing Craft, John D. Barber

Mechanical & Aerospace Engineering Theses & Dissertations

High speed operations in a small craft can be physically punishing and, in some circumstances, even dangerous for the crew. The aspect of small craft operations that make them punishing for the crew is wave slamming generated by wave impacts as the craft is traveling over the seas at high speed.

The initial step of this thesis effort was to perform a literature survey to determine what knowledge existed within the technical and academic community about wave slamming and simulating them with drop tests.

Eventually, a final experiment strongly influenced by the experiment model found in (Protocol 1, 2014) was …

Testing And Analysis Of An Exergetically Efficient 4 K To 2 K Helium Heat Exchanger, Peter N. Knudsen

Mechanical & Aerospace Engineering Theses & Dissertations

Modern experimental nuclear physics programs that utilize advanced superconducting devices require refrigeration below the lambda temperature of helium (2.1768 K) and involve sub-atmospheric helium at some point in the process. They typically operate between 1.8 and 2.1 K (16 to 40 mbar) and can require refrigeration ranging from tens to thousands of watts. These processes are very energy intensive, requiring roughly 850 W/W even for large and well-designed refrigerators, though they can easily require much more. Adiabatic expansion of sub-cooled liquid helium to these sub-atmospheric pressures will result in a two-phase mixture with a large liquid to vapor density ratio. …

Modeling Pyrolysis Of Large Coal Particles With Many Species, Jianqing Li

Master's Theses (2009 -)

Coal currently supplies 40% of the world’s electricity needs, and is one of the most important energy sources. As the initial stage of coal combustion, pyrolysis is a thermal decomposition process which converts coal into light gases and tars, which are subsequently consumed in combustion reactions, as well as solid char. Recently there has been interest in using slow pyrolysis as a stand-alone process for the production of chemicals and fuels from large (mm-scale) coal particles. Simulations can be used to efficiently study the impact of pyrolysis conditions on gas, tar and char yields, as well as gas and tar …

Inverse Structure Functions In The Canonical Wind Turbine Array Boundary Layer, Bianca Viggiano, Moira Gion, Naseem Ali, Murat Tutkun, Raúl Bayoán Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

Wind tunnel measurements for a 3×3 canonical wind turbine array boundary layer are obtained using hot-wire anemometer velocity signals. Two downstream locations are considered, referring to the near- and far-wake, and 21 vertical points are acquired per profile. Velocity increments and exit distances are used to quantify inverse structure functions at both downstream locations. Inverse structure functions in the near-wake show a similar profile for the main vertical locations, but diverge as the moment is increased. In the far-wake, inverse structure functions converge toward a single function for all vertical location and moments. The scaling exponents for inverse structure functions …

Thermo-Mechanical System Identification Of A Shape Memory Alloy Actuated Mechanism, Cody Alexander Wright

Mechanical & Aerospace Engineering Theses & Dissertations

Shape memory alloy (SMA) actuators paired in an antagonistic arrangement can be used to produce mechanisms that replicate human biomechanics. To investigate this proposal, the biomechanical articulation of the elbow by means of the biceps brachii muscle is compared with that of a SMA actuated arm. This is accomplished by parametric analysis of a crank-slider kinematic mechanism actuated, first, with an experimentally characterized SMA wire and then an idealized musculotendon actuator based on actuation properties of muscles published in the literature. Next, equations of motion for the system dynamics of the SMA actuated mechanism are derived and phase portrait analysis …

Changing Trends In Wave Heights In The U.S. Mid-Atlantic Region, Hillary Lane

Civil & Environmental Engineering Theses & Dissertations

The pace and effects of climate change are an area of constant focus for coastal engineers as evolving patterns in the atmosphere worldwide affect the oceans and coasts on a regional and global scale. Surface waves respond to changing wind patterns both locally and from propagating swell, and the difficulty in predicting future wind patterns is well-established. Expectations that climate change will result in more frequent and intense coastal storms and consequently greater wave heights in the North Atlantic are still unrealized, and recent forecasts from a variety of atmosphere-ocean coupled global climate models instead predict decreasing wave heights through …

Effect Of Fiber Material On Ozone Removal And Carbonyl Production From Carpets, Omed A. Abbass, David J. Sailor, Elliott T. Gall

Mechanical and Materials Engineering Faculty Publications and Presentations

Indoor air quality is affected by indoor materials such as carpets that may act as sources and/or sinks of gas-phase air pollutants. Heterogeneous reactions of ozone with carpets may result in potentially harmful products. In this study, indoor residential carpets of varying fiber types were tested to evaluate their ability to remove ozone, and to assess their role in the production of carbonyls when exposed to elevated levels of ozone. Tests were conducted with six types of new unused carpets. Two sets of experiments were conducted, the first measured ozone removal and ozone deposition velocities, and the second measured primary …

Cost Analysis Of Workplace Charging For Electric Vehicles, Florida Solar Energy Center, Richard Raustad

FSEC Energy Research Center®

This report examines the life-cycle costs associated with the operation of electric vehicle supply equipment (EVSE) and the impact that plug-in electric vehicle (PEV) charging may have on commercial building electricity cost. This study assumed that a utility electric meter was attached to each charging station and that 10 kWh of energy was required to replenish the energy consumed during a typical 35-mile daily work commute. Through a life-cycle assessment of typical EVSE equipment, including first cost and maintenance and operating costs, it was found that AC Level 1 or 2 workplace charging can be similar to or lower in …

Case Study Of Quantifying Energy Loss Through Ceiling-Attic Recessed Lighting Fixtures Through 3d Numerical Simulation, Ri Na, Shengmao Lin, Zhigang Shen, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Abstract Air leakage through recessed lighting fixtures has been identified as a common issue that causes extra energy consumption in residential buildings. However, few quantitative studies in this area were found. As such, a preliminary assessment of the magnitude of this type of energy loss was conducted by using three-dimensional (3D) transient computational fluid dynamics (CFD) models. A hypothetical layout of recessed lighting fixtures was designed with boundary conditions of four different seasons, which were obtained from recorded roof/attic temperature data sets. The results of the study indicate that leakage of recessed lighting fixtures could be a significant channel of …

Lennar Ventures Power Purchase Agreement Analysis, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

An analysis was performed to determine the cost-effectiveness of photovoltaic (PV) system Power Purchase Agreements for prototype homes in 13 United States climate locations. EnergyGauge® USA v.5.1 software was used to simulate the energy use of one-story, three-bedroom, 2000 ft² , single-family, frame prototype homes in thirteen representative U.S. climates comprising six IECC climate zones. The same software was used to simulate the power production of PV systems designed to provide approximately 75% of the annual electric energy required by the prototype homes. The net present value (NPV) of the photovoltaic PPA was then calculated as the difference in …

Experimental Study And Performance Characterization Of A Single-Cell Vanadium Redox Flow Battery, Rabiul Islam

Student Theses and Dissertations

Vanadium redox flow battery (VRFB) is a promising technology to store large scale renewable energy. The objective of this research is to investigate the impact of various operating parameters of a lab-scale single-cell VRFB test-bed. The single-cell test-bed VRFB was built and tested with variations of multiple parameters including electrolyte concentrations, current densities, electrolyte flowrates, and ratio of electrolyte volume in tank to cell. The measured data from the tests were analyzed in terms of energy storage capacity, and efficiencies of coulombic, voltage, and energy. It was found that both VOSO4 and H2SO4 concentrations in electrolyte have significant roles in …