Mechanical Engineering Commons^™

Numerical Simulation Model On Irreversibility Of Shock-Wave Process, Longhao Huang

Master's Theses (2009 -)

The objective of this research is to develop a better understanding of the irreversibilities associated with the shock compaction of matter, especially as a result of impact. Due to complex shock processes, experimentation alone cannot fix the material state, since properties such as internal energy, entropy as well as the shock process are not measurable. Thus, in addition to experimentation, analytical and numerical methods are also used to completely characterize the shock process, although they are restricted by underlying constitutive assumptions. Instead of using artificial irreversibility, such as artificial viscosity to simplify and stabilize the numeric shock model, this work …

Admittance Selection For Force Guided Assembly With Optimal Motion, Fernando Rodriguez Anton

Master's Theses (2009 -)

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Current robots lack the precise relative positioning necessary to complete automatic assembly tasks. Several solutions have been proposed. Some approaches use complex vision and force sensing systems to generate corrective motion if misalignment is present in the assembly task. Other solutions rely on generating elastic behavior, known as compliance, between the end eector and the held movable part. This compliant mechanism helps guide the movable part of the assembly into its proper position. The project focuses on designing a process by which passive compliant systems can achieve successful assembly for a range of misalignment and generate error-reducing motion that …

A New Angle On Microscopic Suspension Feeders Near Boundaries, Rachel E. Pepper, Marcus Roper, Sangjin Ryu, Nobuyoshi Matsumoto, Moeto Nagai, Howard A. Stone

Department of Mechanical and Materials Engineering: Faculty Publications

Microscopic sessile suspension feeders are a critical component in aquatic ecosystems, acting as an intermediate trophic stage between bacteria and higher eukaryotic taxa. Because they live attached to boundaries, it has long been thought that recirculation of the feeding currents produced by sessile suspension feeders inhibits their ability to access fresh fluid. However, previous models for the feeding flows of these organisms assume that they feed by pushing fluid perpendicular to surfaces they live upon, whereas we observe that sessile suspension feeders often feed at an angle to these boundaries. Using experiments and calculations, we show that living suspension feeders …

Development Of An Experimental Testbed For Research In Lithium-Ion Battery Management Systems, Nima Lotfi, Poria Fajri, Samuel Novosad, Jack Savage, Robert G. Landers, Mehdi Ferdowsi

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Advanced electrochemical batteries are becoming an integral part of a wide range of applications from household and commercial to smart grid, transportation, and aerospace applications. Among different battery technologies, lithium-ion (Li-ion) batteries are growing more and more popular due to their high energy density, high galvanic potential, low self-discharge, low weight, and the fact that they have almost no memory effect. However, one of the main obstacles facing the widespread commercialization of Li-ion batteries is the design of reliable battery management systems (BMSs). An efficient BMS ensures electrical safety during operation, while increasing battery lifetime, capacity and thermal stability. Despite …

Visual Literacy And The Integration Of Parametric Modeling In The Problem-Based Curriculum, Matthew Benedict Assenmacher

Master's Theses and Doctoral Dissertations

This quasi-experimental study investigated the application of visual literacy skills in the form of parametric modeling software in relation to traditional forms of sketching. The study included two groups of high school technical design students. The control and experimental groups involved in the study consisted of two randomly selected groups of students. The participants were exposed to eight weeks of technical drawing and parametric modeling instruction prior to the start of the study.

The potential applications of emerging technologies for the purpose of integrating visual literacy into the curriculum are not fully understood. Society is moving towards a more immediate …

Dimensionless Criteria For Selecting Tidally-Influenced Advective-Dispersive Desalination Brine Mixing Plume Characterization Models, Alireza Shahvari

Civil & Environmental Engineering Theses & Dissertations

The very nature of requirements for implementing a desalination process is highly spatial due to the need to secure both a source for the operation and sink for brine dilution. Thus, the applicable coastal location is bound to natural tidal mixing characteristics and subjected to a near- or a far-field availability for source and sink. Mixing characteristics of coastal waters are very different from one point to another due to the spatiotemporal tidal characteristic in loco in a manner that it can vary from being highly advective to completely dispersive dominant. Once a location is identified, estimation of corresponding water …

Design Exploration And Analysis Of Carbon-Infiltrated Carbon Nanotube Vascular Stents, Darrell John Skousen

Theses and Dissertations

The purpose of this research was to design, develop, and test coronary stent designs composed of carbon-infiltrated carbon nanotubes (CI-CNTs). Coronary stents currently have two major complications: restenosis and thrombosis. CI-CNT stents have potential to address both of these issues, and therefore may provide improved clinical outcomes. CI-CNT stent geometry is patterned using high-resolution photolithography that provide advantages in design possibilities.To develop a coronary stent, a standard design process was followed including: background, design specifications, concept generation, development, analysis, and testing. Background research was first completed and general design specifications for coronary stent performance were compiled. Multiple design concepts were …

Energy And Economic Optimization To Achieve Near Zero Energy Homes In Europe: Implications Of Inclusion Of Lighting And Appliances, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Achieving annual net zero energy use in homes has been demonstrated as feasible in dozens of monitored projects in the United States.[1] In particular, very low energy use homes in Europe have been proven within the Passivhaus approach.[2] Achieving 'nearly zero energy buildings' (NZEB) has also been established as a vital objective over the next decade within the European Union (EU) (Boermans et al., 2011). However, reaching this result at the lowest possible cost remains a key challenge around the world. Balancing renewable power generation with energy efficiency will be vital in Europe as anticipated by Voss, Musall and Lichtmeß.[4] …

Technical Subtopic 2.1: Modeling Variable Refrigerant Flow Heat Pump And Heat Recovery Equipment In Energyplus, Florida Solar Energy Center, Richard Raustad

FSEC Energy Research Center®

The University of Central Florida/Florida Solar Energy Center, in cooperation with the Electric Power Research Institute and several variable-refrigerant-flow air conditioning (VRF AC) manufacturers, provided a detailed computer model for a VRF AC system in the United States Department of Energy's (U.S. DOE) EnergyPlus' building energy simulation tool. No other simulation tool currently has the capability to accurately model this state-of-the-art VRF heating, ventilating, and air conditioning (HVAC) equipment. Detailed laboratory testing and field demonstrations were performed to measure equipment performance and compare this performance with that predicted by the use of this new model through computer simulation.

This project …

Bipedal Locomotion, Jamie Nichol, Dr. Paul Eastman

Journal of Undergraduate Research

Creating an artificial biped (two legged machine) has proven a challenge. The first stage of the project, designing and building the mechanical frame, has required that I study several engineering disciplines. I have also learned many lessons by trial and error.

Enhanced Reducibility And Conductivity Of Na/K-Doped Srti0.8Nb0.2O3, Guoliang Xiao, Sirikanda Nuansaeng, Lei Zhang, Suwit Suthirakun, Andreas Heyden, Hans-Conrad Zur Loye, Fanglin Chen

Faculty Publications

Donor and acceptor co-doped SrTiO₃ materials have shown interesting features in their conductivity and reducibility. In this work, 10 mol% Na⁺ or K⁺ as acceptor dopants have been introduced into the A-site of donor-doped strontium titanate, SrTi_0.8Nb_0.2O₃, and the doping impact on their properties has been studied. By doping with Na or K, the sinterability of SrTi_0.8Nb_0.2O₃ in reducing atmospheres has been improved. Na_0.1Sr_0.9Ti_0.8Nb_0.2O₃ and K_0.1Sr_0.9Ti_0.8Nb_0.2O₃ show metallic …

Flame Jet Impingement Heat Transfer, Todd Moss, Dr. Brent Webb

Journal of Undergraduate Research

Impinging flame jets are used widely in industry and manufacturing because of their high heat transport characteristics and tight spatial control of the heating. The technique is used in heating or re-heating of stock in the metals and glass industries, and in welding and soldering operations. However, these impinging flame jets are not well understood, and few studies reporting local and average heat transfer characteristics exist in the open literature which might be used by designers (Baukal and Gebhart, 1995a, 199b). The purpose of this research is to experimentally characterize and correlate the local and average heat transfer behavior of …

Design Of An Aerospike Rocket Nozzle For Integration With A Hybrid Rocket Motor, Jeffrey L. Smith, Dr. Paul F. Eastman

Journal of Undergraduate Research

Safe, reliable, technologies are needed to launch a new generation of astronauts and space tourists into space. The aerospike nozzle is more efficient than traditional bell shaped nozzles and is safer because of lower combustion chamber pressure. These excellent performance characteristics have never before been tested in conjunction with a hybrid rocket motor. This paper presents the design and testing method for an aerospike rocket.

Correlating Skin Vibration With Radiated Sound During Speech, Jason Schulthess, Dr. Scott Thomson

Journal of Undergraduate Research

The intent of this research was to study correlation between the sound that is radiated during human speech and the resulting vibrations that occur in the skin in regions of the head and neck. This report includes results from two parts of this research. First are the measurement results and the comparisons of frequency content obtained from the vibration of the skin at various locations on the head and neck. The second is a presentation of the results examining the frequency content of the measurement device; this study was motivated by preliminary testing results that revealed possible interference due to …

Design Of Compliant Prosthetic Ankle Joints Using A Kinematic Model, Jason M. Wiersdorf, Robert Robins, Spencer P. Magleby, Larry L. Howell, Robert H. Todd

Journal of Undergraduate Research

The complex system of bones, muscles, ligaments and tendons in the human ankle allow it to withstand high compression impacts, to move in multiple degrees of freedom, and to transfer energy from the leg to the foot while walking or running.

Use Of Signal Processing Methods To Improve Speech Intelligibility In Throat Microphones, Daniel J. Andelin, Dr. Scott Thomson

Journal of Undergraduate Research

Effective communication, vital to successful operations in many sectors, including military, business, and industry, depends largely on the receiver’s ability to accurately interpret the transmitted signal, generally referred to as speech intelligibility (SI). The presence of elevated noise can be seriously detrimental to SI. To reduce ambient noise in communication through audio microphones, it is possible to use a throat microphone (TM), which senses vocal fold vibrations through the skin on the speaker’s neck, as opposed to detecting the airborne sound wave emanating from the speaker’s mouth, as in standard microphones . Unfortunately, the position of the TM on the …

Synthetic Model Of Vocal Folds, Todd C. Groesbeck, Dr. Scott Thomson

Journal of Undergraduate Research

The influence and treatment of human vocal fold scarring is a topic of great interest to the speech community (clinicians, surgeons, educators, etc). Understanding how voice production occurs “is sought in order to improve predictive, diagnostic, and corrective practices related to vocal fold health” . When a patient undergoes vocal fold surgery, scarring frequently occurs. The same surgery intended to heal the vocal fold thus leaves it damaged; scarring results in impaired vibration and prevents the individual from normal, healthy voice use.

Terrain Following In Unmanned Air Vehicles Using Optic Flow Sensors, Blake Barber, Dr. Tim Mclain

Journal of Undergraduate Research

A key enabling technology that will allow the U.S. Military to maintain information superiority in the 21st century is the development and implementation of Unmanned Air Vehicle (UAV) technology. Especially critical to the support of the small special operations units conducting the asymmetric warfare of the 21st century will be the development of mini and micro UAV technology. Mini and micro UAV technology will enable foot soldiers to hand launch and recover small, robust reconnaissance aircraft capable of providing real-time video surveillance and real-time target acquisition. These capabilities will allow soldiers to have the full situational awareness they need for …

Frequency Response Of Skin Vibration On The Head And Neck During Speech, Ben Pence, Dr. Scott Thomson

Journal of Undergraduate Research

During speech, the vocal folds vibrate resulting in audible sounds. In addition to being transmitted through the vocal tract these vibrations are also transmitted through several layers of various types of tissue throughout the head and neck, resulting in small, but measurable, skin surface vibration. Contact microphones sense these skin surface vibrations for speech transmission as opposed to acoustic microphones that sense air vibrations that radiate from the mouth.

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• Dr. Mujibur Khan, Assistant Professor of Mechanical Engineering, Awarded $153,000 NSF Grant