Mechanical Engineering Commons^™

Emg-Emg Coherence Analysis Of Elbow And Shoulder Muscles, Manu Stephen

All Theses and Dissertations (ETDs)

Motor coordination can be described by the activation of a few intermuscular coordination patterns, or muscle synergies. Muscle synergy can be defined as a relatively fixed pattern of activation across a set of muscles. The neural mechanisms underlying muscle synergies remain to be fairly unknown. Through a muscle synergy study [13], co-activation in muscle pairs was discovered through a non-negative matrix factorization: NMF) analysis. In order to evaluate the same muscles under the frequency domain, coherence analysis: a correlational method) was used. Additionally, a comparison can be made to determine if the resulting muscle pairs overlap with the muscle pairs …

Kinematic Synthesis Of Planar, Shape-Changing, Rigid Body Mechanisms For Design Profiles With Significant Differences In Arc Length, Shamsul A. Shamsudin, Andrew P. Murray, David H. Myszka, James P. Schmiedeler

Mechanical and Aerospace Engineering Faculty Publications

This paper presents a kinematic procedure to synthesize planar mechanisms capable of approximating a shape change defined by a general set of curves. These “morphing curves,” referred to as design profiles, differ from each other by a combination of displacement in the plane, shape variation, and notable differences in arc length. Where previous rigid-body shape-change work focused on mechanisms composed of rigid links and revolute joints to approximate curves of roughly equal arc length, this work introduces prismatic joints into the mechanisms in order to produce the different desired arc lengths. A method is presented to iteratively search along the …

Effects Of Time Varying Background Noise Conditions On Human Perception And Performance, Andrew H. Hathaway

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

This thesis was designed to study the effects of changing noise conditions on human perception and performance. In two phases, participants were exposed to a number of noise conditions and their performance on an arithmetic task involving short-term memory was monitored and their subjective perception of noise conditions was collected via questionnaires.

In the first phase, participants were tested while being subjected to RC-29(H) and RC-47(RV) conditions created by broadband noise fluctuating on different time intervals, resembling the changing noise conditions potentially found in modern HVAC systems. These intervals varied from two minutes to ten minutes. Results show a significant …

Burnout, No, Flame Temperature, And Radiant Intensity From Oxygen-Enriched Combustion Of A Hardwood Biomass, Joshua David Thornock

Theses and Dissertations

Increasing concern for energy sustainability has created motivation for the combustion of renewable, CO2 neutral fuels. Biomass co-firing with coal provides a means of utilizing the scaled efficiencies of coal with the lower supply availability of biomass. One of the challenges of co-firing is the burnout of biomass particles which are typically larger than coal but must be oxidized in the same residence time. Larger biomass particles also can increase the length of the radiative region and alter heat flux profiles. As a result, oxygen injection is being investigated as a means of improving biomass combustion performance.An Air Liquide designed …

Mass Production Of Β-Silicon Carbide Nanofibers By The Novel Method Of Forcespinning, Alfonso Salinas

Theses and Dissertations - UTB/UTPA

Non-oxide Ceramics such as silicon carbide have very unique properties, for example high toughness, thermal stability, wear resistant, and thermal shock resistance these properties make these ceramic fibers excellent for high temperature applications. Here we present the development of Silicon Carbide nanofibers utilizing a Polystyrene/Polycarbomethylsilane solution as the precursor materials. The Forcespinning ® was performed under a controlled nitrogen environment to prevent fiber oxidation. Characterization was conducted using scanning electron microscopy, x-ray diffraction, and thermogravimetric analysis. The results show successful formation of high yield, long continuous bead-free nanofibers with diameters ranging from 280nm to 2 micron depending on the selected …

Thermal Analysis Of Carbon Nanofiber Reinforced Isotactic Polypropylene, Anna Alicia Hernandez

Theses and Dissertations - UTB/UTPA

Isotactic Polypropylene (IPP) is a commonly known thermoplastic that has unique properties include being light weight, high performance, impact strength, tensile strength, elongation, and high temperature properties. The use of vapor grown carbon nanofiber (VGCNF) reinforcements on polypropylene has shown to produce high specific modulus, strength, electrical and thermal properties on specimens. Thermogravimetric (TGA) investigations on the thermal degradation of isotactic polypropylene – vapor grown carbon nanofibers composites in nitrogen were reported. The mass evolution as a function of temperature is a single sigmoid for both polypropylene and polypropylene loaded with VGCNF. The inflection temperature of these sigmoids increases as …

Improving Global Impact: How The Integration Of Remotely Reporting Sensors In Water Projects May Demonstrate And Enhance Positive Change, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

This article argues that improved feedback on the actual impact of development programs may ensure the success of poverty reduction interventions such as water filters, water pumps, latrines, and cookstoves.

Computer-Based Stereoscopic Parts Recognition For Robotic Applications, Ahmad A. Fayed

UNLV Theses, Dissertations, Professional Papers, and Capstones

Most of robotic handling and assembly operations are based on sensors such as range and touch sensors. In certain circumstances, such as in the presence of ionizing radiation where most customary sensors will degrade over time due to radiation exposure, these sensors won't function properly. Utilizing two or more cameras (stereo vision) located outside the target zone and analyzing their images to identify location and dimensions of parts within the robot workspace is an alternative for using sensors. Object Recognition is affected by the light condition which oftentimes causes the gray-scale or red, green, and blue values to have a …

Experimental And Finite Element Studies Of Shock Transmission, Eldon Jerry Goddard

UNLV Theses, Dissertations, Professional Papers, and Capstones

Composite materials are more widely used today in engineering products than ever before. Shock transmission in jointed composite sections needs to be investigated to understand the affect of composite materials on the dynamic response of the system. There exists limited published work on transient shock propagation through composite sections. The aim of this study is to analyze the transient behavior of joints in composite materials subjected to low impact loads and to develop a computational model that provides an improved physics based shock model. The jointed connection will be investigated experimentally and using Finite Element Analysis (FEA). The bolted joint …

Heat Transfer Experiment: Energy Conservation, Ben Ward, Brett Wallace, Ryan Waltman

Mechanical Engineering

This proposal, prepared for the Mechanical Engineering Department by the HTEC design team will redesign and replace the current energy conversion lab that is inaccurate and out of date. The team will evaluate methods of energy conversion, specifically using braking systems, as well as existing labs in order to design an accurate and relatable experiment for this lab. The project team will work with Professor Kim Shollenberger in order to design an experiment that demonstrates energy conversion through the first law of thermodynamics while utilizing a common device that is practical in student’s lives. The final result of this project …

Low-Cost Scheffler Solar Concentrator For The Developing World, Darren Sholes, Jason Morgan, Nicholas Fuller

Mechanical Engineering

This report will outline an approach to design, test, and build a low-cost Scheffler solar concentrator to be used for safer, sustainable and cost effective cooking in the developing world. The function of Scheffler concentrators and a proposed method to create one in an economic, environmentally conscious manner is summarized. If successful, the design will be presented in a way that is readily and freely available to anyone in the world. The authors have examined existing technology and researched the availability and cost of different materials. Analysis was performed in order to verify the feasibility of the different design ideas …

Design And Construction Of An Omni-Directional Soccer Ball Thrower, Andrew James Marquette

Undergraduate Honors Capstone Projects

Introduction

We are ODST the Omni-Directional Soccer Ball Thrower team which designed the soccer ball launching machine. Working in direct correlation with the project sponsor John Meade from Athlonic Sports this is the report outlining the soccer ball thrower. John from Athlonic Sports came up with the overall project and initial project vision. There are soccer ball launching machines on the market but lacking mobility, not amiable and are heavy. The design needed to be mobile, amiable, lightweight, and have a soccer ball capacity incorporated into the machine. This will allow coaches to repeatability place the soccer ball in certain …

Knowledge Extraction From Work Instructions Through Text Processing And Analysis, Abhiram Koneru

All Theses

The objective of this thesis is to design, develop and implement an automated approach to support processing of historical assembly data to extract useful knowledge about assembly instructions and time studies to facilitate the development of decision support systems, for a large automotive original equipment manufacturer (OEM). At a conceptual level, this research establishes a framework for sustainable and scalable approach to extract knowledge from big data using techniques from Natural Language Processing (NLP) and Machine Learning (ML). Process sheets are text documents that contain detailed instructions to assemble a portion of the vehicle, specification of parts and tools to …

Effects Of Iteration On Concept Development, Shivraj Ranganathan

All Theses

Iteration in the conceptual design stage is defined as repetition of design tasks to incorporate new information. A more concise definition of iteration relevant to this research would be the progression of design through different abstraction levels or design stages, defining and refining design solutions while progressing from initial concepts to a more detailed design. Although it is believed that iteration has a positive effect on the quality of ideas in the design process, this experimental study presents an opportunity to determine the effects of iteration on quality of concepts and the factors that lead to increased quality of concepts. …

Knowledge Base Representation With Axiomatic Design Rules For Concept Level Up Implement In Ontological Framework, Zhuochen Shi

All Theses

Axiomatic Design has been applied and developed as a tool, offering a scientific basis for design and improving design activities. Axiomatic Design has been used in various fields such as software system design, structure design, and product design. However, several challenges and limitations exist in Axiomatic Design including: the inconsistency in identifying design parameters, existence of coupled design, and multiple groups of functional requirements and design parameters. Aimed at using Axiomatic Design to generate conceptual solutions in engineering design while overcoming its limitations, a formal ontology is developed. The ontology defines functional requirements, design parameters, concepts, components and variables and …

Analyzing Requirement Type Influence On Generated Solutions, Emily Worinkeng

All Theses

Several ideation methods are available and used by engineering designers to enable the generation of alternative designs [1]. However, there has been little work done to understand the role that the design problem given to participants plays in the ideation process. The contribution of this research is found through the proposed guidelines with respect to the type of requirements to include as part of the design problem in order to achieve the desired quantity, quality, novelty, and variety of solutions during the early stages of the design process. This work is the first attempt at analyzing the effect of requirement …

A Study Of Gallery Method To Increase Idea Quality In Conceptual Design, Liz Mathew

All Theses

The objective of this research is to evaluate whether gallery method increases idea quality in conceptual design for engineering design problems. The gallery method is a group ideation process which allows individuals to first generate ideas individually, followed by pooling of ideas to conduct group ideation. Design engineers are often encouraged to work in groups to generate concepts and solutions for design problems. However, past research argues that individual ideation results in higher quality design concepts compared to the group ideation methods. The limitations of group ideation such as free riding, production blocking, evaluation apprehension, and goal incongruity are identified …

An Exploratory Study On The Effects Of Goal Alignment, Interventions, And Motivational Factors On Innovative Engineering Design Projects, Blake Linnerud

All Theses

Innovation has become an important facet of engineering design, both in industry and the academy. Many senior-level engineering design courses encourage students to develop innovative solutions to open design projects from industry sponsors. Like industry, these academic problems are tackled by teams of students. Student teams that function at the highest level are more likely to reach the innovative solutions for which they are searching. The research presented in this work focuses on two main areas: (1) understanding what motivates engineers when working on innovative design projects and (2) determining the effects of goal alignment interventions on design teams working …

Enhancing Energy Efficiency In Connected Vehicles Via Access To Traffic Signal Information, Grant Mahler

All Dissertations

This dissertation expounds on algorithms that can deterministically or proba-bilistically predict the future Signal Phase and Timing (SPAT) of a traffic signal by relying on real-time information from numerous vehicles and traffic infrastructure, historical data, and the computational power of a back-end computing cluster. When made available on an open server, predictive information about traffic signals’ states can be extremely valuable in enabling new fuel efficiency and safety functionalities in connected vehicles: Predictive Cruise Control (PCC) can use the predicted timing plan to calculate globally optimal velocity trajectories that reduce idling time at red signals and therefore improve fuel efficiency …

Me-Em Enewsbrief, December 2013, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Understanding The Role Of Requirements In Engineering Design By Novices, Shraddha Joshi

All Dissertations

Requirements play a critical role in the design process. The broader impact of this research is to develop a systematic understanding of the current use of requirements with an ultimate goal to develop guidelines and recommendations for more effective use of requirements throughout the design process. Thus, this research begins to answer the question about what is the role of requirements in design process and, specifically, its role in idea generation? The answer to this question is explored in three phases. The first phase is to understand how requirements are currently taught to students. To that end, two surveys were …

Primary Resonance Behavior Of Expanded Polymer Cushion Material Under Low-Intensity Harmonic Excitations, Gregory Batt

All Dissertations

The demand to lower costs and reduce the amount of packaging materials utilized in a packaged-product system has placed increased importance on the development of tools to model the behavior of packaging systems. In this dissertation, the free and forced vibration response of a nonlinear, distributed-parameter model of a viscoelastic rod with an applied tip-mass is used to investigate the response of expanded polymer cushion materials to low-intensity harmonic excitations. The rod and tip-mass represent an idealized packaged product system. A nonlinear model is developed from constitutive relations. A classical Maxwell-Weichert model, represented via a Prony series, is used to …

Development Of A Hybrid Vehicle Powertrain Test Laboratory, Bennet Samuel Soundarraj

Doctoral Dissertations and Master's Theses

During the last two years, Embry-Riddle Aeronautical University has installed and tested a fully functional eddy-current chassis dynamometer testing facility on campus. An automotive test facility requires a systems engineering approach to install, calibrate and commission a chassis dynamometer. This thesis shows that, the dynamometer test facility was successfully installed, commissioned and documented to safely support the power train development and testing. We can currently test the EcoCAR vehicle and a number of other front-wheel-drive vehicles at our university campus using the eddy current chassis dynamometer.

Mode I Fracture Toughness Of Eight-Harness-Satin Carbon Cloth Weaves For Co-Cured And Post-Bonded Laminates, Josh E. Smith

Master's Theses

Mode I interlaminar fracture of 3k 8-Harness-Satin Carbon cloth, with identical fill and weft yarns, pre-impregnated with Newport 307 resin was investigated through the DCB test (ASTM D5528). Crack propagations along both the fill and weft yarns were considered for both post-bonded (co-bonded) and co-cured laminates. A patent-pending delamination insertion method was compared to the standard Teflon film option to assess its applicability to mode I fracture testing. The Modified Beam Theory, Compliance Calibration method, and Modified Compliance Calibration method were used for comparative purposes for these investigations and to evaluate the validity of the proposed Equivalent Stiffness (EQS) method. …

Ultrasonic Propagation And Scattering In Pearlitic Steel, Hualong Du

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

Diffuse ultrasonic backscatter measurements have been especially useful for extracting microstructural information and for improving flaw detection in materials. In this dissertation, this approach is applied to inspection of railroad wheels. To improve the wear resistance, the tread surfaces of railroad wheels are usually quenched with water to increase the hardness. The pearlite phase of iron, characterized by alternating ferrite and cementite phases, is created by the quenching and the lamellar spacing within grains increases progressively from the quenched tread surface to deeper locations due to the non-uniform cooling rate. The quench depth is an important parameter governing the wheel …

Near-Infrared Surface-Enhanced Fluorescence Using Silver Nanoparticles In Solution, Michael D. Furtaw

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Fluorescence spectroscopy is a widely used detection technology in many research and clinical assays. Further improvement to assay sensitivity may enable earlier diagnosis of disease, novel biomarker discovery, and ultimately, improved outcomes of clinical care along with reduction in costs. Near-infrared, surface-enhanced fluorescence (NIR-SEF) is a promising approach to improve assay sensitivity via simultaneous increase in signal with a reduction in background. This dissertation describes research conducted with the overall goal to determine the extent to which fluorescence in solution may be enhanced by altering specific variables involved in the formation of plasmonactive nanostructures of dye-labeled protein and silver nanoparticles …

Structural And Magnetic Characterization Study Of Hfco7 Alloy With Substitutions Of Si, Ti, Fe, Mn And B, Jacob A. Lewis

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Magnetic materials are a critical component of the modern technological society. The market of high-energy product hard magnets is dominated by the rare-earth element containing neodymium-iron-boron (NdFeB) magnets. As a result of worldwide demand coupled with trade restrictions on rare-earth minerals, new magnet compositions are explored to reduce pressure on the already strained market. The hafnium-cobalt alloy system has shown promise as a candidate for filling the gap in saturation magnetization between rare-earth containing alloys and those made with abundant elements. This study explores the magnetic effects of silicon, titanium, iron, manganese and boron substitutions in the hafnium-cobalt-7 (1:7 atomic …

Experimental Study On The Effect Of Air Flow On Soap Bubble Formation, John M. Davidson

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Soap bubbles are a common interfacial fluid dynamics phenomenon having applications such as buoyant hollow spherical fillers and flow visualization of large scale airflows. In contrast to the dynamics of liquid drops in gas and gas bubbles in liquid, the dynamics of soap bubbles has not been well documented, possibly because soap bubbles have gas-liquid-gas interfaces. Having the thin-liquid-film interface seems to alter the characteristics of the bubble/drop creation process. Thus, the main objective of this study is to experimentally examine how airflow develops and interacts with the soap liquid film as the film stretches and finally collapses to pinch-off. …

Constant Voltage Hot-Wire Anemometry For The Boundary Layer Data System, Hon Yee Li

Master's Theses

To continue the development of the Boundary Layer Data System (BLDS), a constant voltage hot-wire anemometer (CVA) is implemented into the BLDS for flight-testing. The hot-wire anemometer was chosen as an alternative to the traditional pressure probe because of the ability to measure both average velocity and fluctuating velocity within the boundary layer. Previous work done on the benchtop has led to the design of miniaturization, flight-capable hardware for the BLDS. The next step in the development of the BLDS – CVA calls for quantifying the accuracy of the boundary layer measurements measured by the CVA system. To do this, …

Development And Validation Of A Human Knee Joint Finite Element Model For Tissue Stress And Strain Predictions During Exercise, Spencer D. Wangerin

Master's Theses

Osteoarthritis (OA) is a degenerative condition of cartilage and is the leading cost of disability in the United States. Motion analysis experiments in combination with knee-joint finite element (FE) analysis may be used to identify exercises that maintain knee-joint osteochondral (OC) loading at safe levels for patients at high-risk for knee OA, individuals with modest OC defects, or patients rehabilitating after surgical interventions. Therefore, a detailed total knee-joint FE model was developed by modifying open-source knee-joint geometries in order to predict OC tissue stress and strain during the stance phase of gait. The model was partially validated for predicting the …