Mechanical Engineering Commons^™

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

Design Of Compliant Bicycle Brake, Todd R. Coon, Dr. Larry Howell

Journal of Undergraduate Research

Shimano corporation, the market leader in bicycle components, sells a class of brakes titled “Vbraketm” that has a strong braking force and travels in a horizontal motion. The V-brake (Fig. 1) uses a four-bar mechanism to direct its motion. The goal of this design project was to use new technology to achieve the same performance as the V-brake while significantly decreasing the part count and the complexity of the design.

Friction Stir Welding Of Hsla Steel, Sterling Anderson, Dr. Tracy Nelson

Journal of Undergraduate Research

In response to industrial need for a high-strength, weldable, malleable, and corrosion resistant steel the United States Navy developed a high-strength, low-alloy steel known as HSLA 65. Because of its superior mechanical properties and low cost, HSLA 65 is being increasingly used in pipeline, naval, and automotive industries. The important structural role it plays in these industries requires not only that it be weldable, but that, once welded, it maintain specified strength, ductility, and chemical composition values to avoid failure during extreme loading conditions. To achieve these properties, HSLA requires an efficient welding method that will not degrade its strength. …

Improving Micro Air Vehicles, Andrew Hosford, Dr. Deryl Synder

Journal of Undergraduate Research

Recently, there has been increased interest in the development of micro air vehicles (MAVs) (Figure 1) to perform reconnaissance, surveillance, and other small operations best suited for air vehicles with maximum dimensions of six inches. In order to develop successful air vehicles, it is imperative to have correct fluid flow modeling. As of late, current modeling tools used to design and analyze full-scale aircraft do not work well for MAVs[1]. This lack of appropriate tools has lead current research to take a trial and error approach to design of MAVs—a very expensive and inefficient technique.

Evaluation Of A Compliant Out-Of-Plane Micro-Mechanical Mechanism, Jeff Young, Dr. Larry Howell

Journal of Undergraduate Research

Much research is being done around the world in the field of micro-electro-mechanical systems (MEMS). MEMS are devices such as linkages, actuators, gears and motors built on a scale of microns. MEMS have many potential applications in medical science, electronics and other areas where smaller, more intricate, and more innovative solutions are continually required. Essential to the practicality of MEMS is the ability to design for predictable and reliable behavior. The extremely small size of these devices presents difficulty in realizing a design. Joining separate elements into operative assemblies is very difficult at the micro scale. A sound solution to …

Stress-Induced Development Of Human Vocal Fold Morphology, Kendall Teichert, Dr. Scott Thomson

Journal of Undergraduate Research

Ramig and Verdolini state: “it has been estimated that 3% to 9% of the total population in the United States has a voice disorder.” One way to better understand voice disorders is to learn about the development of the structures and properties, or morphology, they affect. Much study has been done on the morphology of the human vocal folds. As explained by Hirano et al the vocal fold is made up of two parts: a cover (mucosa) and body (muscle). Hirano further explains that the mucosa is composed of various layers which include the mucosa epithelium and the lamina propria. …

Charpy Impact Study Of Friction Stir Welded X-65 Steel, David Segrera, Dr. Tracy Nelson

Journal of Undergraduate Research

Industrial need for a high-strength, ferritic steel exhibiting desirable weldability, malleability, and corrosion resistance properties has led to the development of high strength, low alloy (HSLA) X-65 Steel. This class of steel uses small amounts of alloying material and very little carbon to make it more corrosion resistant than normal carbon-containing steels. As HSLA has gained popularity in automotive, naval, and other industries, the inherent need for better welding processes has arisen.

A Self-Powered Wireless Microphone, Joel Neff, Dr. Brian D. Jensen

Journal of Undergraduate Research

The idea for our project was to use vibrations from the human vocal folds to harvest energy during speech. This energy would then be used to power a wireless throat microphone, which would acquire a speech signal and then transmit it to a fixed receiver for communications systems. The measurements we took estimated that human vocal folds could produce vibrations with amplitudes on the order of 1-5 m/s2 at the skin surface on the throat. One research study done by Shad Roundy at UC-Berkeley demonstrated that a device capable of producing 300 µW of power could be driven off of …

Scar Effects On Vocal Fold Vibration, Todd Groesbeck, Dr. Scott Thomson

Journal of Undergraduate Research

The influence of scarring on the vocal folds is of great interest to the speech community. Surgeons, educators, and vocalists all have interest in understanding what causes vocal fold damage, and how such damage may be repaired. Frequently, repair requires surgery, and the surgery may result in scarring. Scarring results in impaired vibration, thus altering the quality of the individual’s voice.

Visual Based Reverse Engineering, C. Porter Bassett, Dr. C. Greg Jensen

Journal of Undergraduate Research

Reverse engineering, or the process of taking an implemented idea and taking it back to the design stage, has many applications in many different types of engineering. One common application of reverse engineering is to take a manufactured part, measure its dimensions and shape, and then make new drawings or Computer-Aided Design (CAD) models of the part. When done manually, this is a very tedious process that includes measuring dimensions and manually inputting them into the CAD program. This also leaves a lot of room for human error either on measuring the part or inputting the dimensions. The reverse engineering …

Computational Analysis Of Prosthetic Voice-Producing Elements, Britton Olson, Dr. Scott L. Thomson

Journal of Undergraduate Research

Many voice disorders impede normal speech production. In severe cases such as laryngeal carcinoma, the total laryngectomy procedure is required, resulting in the loss of the natural ability to produce sound for speech. In this case synthetic forms of speech are employed. One method of synthetic speech that has demonstrated potential is a “voice-producing element” (VPE) . Recent VPE designs consist of two latex membranes within a cylindrical housing that is placed in the tracheoesophageal wall in a “double-reed” configuration. Air flowing from the lungs between the membranes results in regular, large-amplitude, self-sustained vibrations. The membranes are loaded on the …

Ultra-Small Scale Hydroelectric As A Supplemental Energy Source, Andrew Thompson, Dr. Daniel Maynes

Journal of Undergraduate Research

For centuries water has been used as a source of power; from the middle ages where waterwheels were used for simple mechanical tasks to the 21st century where large hydroelectric power plants supply megawatts of electricity to the power grid. In recent decades developing and remote regions in Tibet, Laos, Uganda and parts of Latin America, have begun using small scale hydroelectric generators to provide electricity to their areas. With the rising concerns of greenhouse gas emissions, developed nations have also begun to look into ‘small scale hydro.’1

Development Of Models Of Laryngeal Cartilage Using Mri Images, Brianne Hamilton, Dr. Scott L. Thomson

Journal of Undergraduate Research

The study of vocal fold vibration allows for greater understanding of how speech production occurs and of the prevention, diagnosis, and treatment of associated physiological disorders. Until now an environment to test vocal fold models which are anatomically similar in both form and function has not been available. It was necessary to have a larynx model in which artificial vocal folds can be placed and subjected to conditions found in the human body in order to attain a more comprehensive understanding of vocal folds and their function. This project was part of a team working with Dr. Scott L. Thomson …

Polyurethane (Pu) Foam Synthesis And Lean Manufacturing An Effective Business Suitable In Developing Countries, Sebastian Acosta, Danny Parades, Dr. Robert Todd

Journal of Undergraduate Research

Our ORCA project was motivated by the realization that many South American countries have not taken full advantage of the polyurethane industry. The manufacturing of PU and its applications may contribute to the economic and social growth in less-developed nations. This may be accomplished if this potential industry is appropriate for development by small/medium enterprises and other business partnerships. The main goal of our ORCA research project was to learn by study and personal experience if the synthesis of PU foam truly is a suitable business in developing nations.

Development Of Synthetic Composite Materials To Simulate Vocal Fold Tissue, Allyson Pulsipher, Dr. Scott Thomson

Journal of Undergraduate Research

Over the past 25 years, research has been done to analyze the response of vocal fold tissue to tensile loading. Although the research provided better understanding of vocal fold behavior, there has been significant variability in the results of each research endeavor. Many factors may have contributed to the differences, such as dissimilar experimental set-ups, difficulty of obtaining and analyzing vocal fold samples, etc. However, the most significant factor of variance is most likely related to the structure of the tissue itself.

Palatometer, Art Krahenbuhl, Dr. Brian Jensen

Journal of Undergraduate Research

The palatometer is a device previously designed by Dr. Sam Fletcher to aid in his work of speech therapy. The device consists of a series of sensors laid out on a grid that is attached to a mold of the user’s palate. As the user talks, the sensors react to the places where the tongue touches and sends a signal through wires to a processing chip, housed in a little black box. This black box is suspended around the user’s neck, and relays the data from the mouth to a computer that creates a digital representation of the sensor’s information …

A Race Vehicle Data Acquisition System, B. Taylor Newill, Dr. Mark Colton

Journal of Undergraduate Research

The Society of Automotive Engineers hosts the annual Formula SAE student design competition. This year 70 teams will design, build, and race a one man, open-wheeled road racer. Formula SAE is considered by many to be the most prestigious university engineering design competition in the world. For the first time, a team of undergraduate BYU students will participate in the Formula SAE competition.

Merging Creative Design And Cad Learning Activities In A Product Design Programme, Pearl O'Rourke, Colm O'Kane, Leslie Smith, Michael Ring

Conference Papers

Traditional learning and teaching methods for creativity differ from those used in a scientific context. Although the creative process can benefit from a certain level of prescription and structural constraint - with time allocated to research, problem definition, conceptualisation and idea development - flexibility and fluidity are necessary for creative innovation. In contrast, the more linear and rigid pedagogies associated with science and engineering education facilitate efficient learning of subjects such as those based on software packages, manufacturing and materials theory or mechanics. This paper describes the development of a project which aims to establish constructive links between the learning …

Progressing Bicycle Design For People With Hip Disarticulation, Luke Rasmussen, Dr. Mark Colton

Journal of Undergraduate Research

People with hip disarticulation are those who have had a leg surgically removed above the hip, taking away every muscle and movement in one of their limbs. A surgery of this type makes it extremely difficult for its recipients to lead an active lifestyle. This project aimed to design a bicycle for use by people with hip disarticulation, thus enabling them to maintain an active and healthy lifestyle despite their obstacles.