Mechanical Engineering Commons^™

Underwater Object Detection And Identification Using Distributed Pressure Sensors, Audrey Maertens

Link Foundation Ocean Engineering and Instrumentation Fellowship Reports

Underwater vision is usually limited. Object detection and identification is therefore one of the main challenges of underwater navigation. A new sensing modality, specifically developed for underwater environments, would greatly increase the scope of underwater missions. Taking inspiration from the lateral line of fish, I believe that pressure sensing can be a viable alternative to vision in order to detect and identify obstacles. Recent advances in the area of micro-engineering will soon enable to build sensors that match the size and mimic the functions and organization of the lateral line. However, little is known about how the pressure distribution along …

Development Of A Predictive Model For Bulk-Flow Through A Porous Polymer Membrane Tube, Aaron Robert Meles

UNF Graduate Theses and Dissertations

While extensive mathematical and numerical work has been done in terms of modeling the mainstream flow in a tube with porous walls, very little has been done experimentally to confirm these various solutions, and what has been done has focused on large sintered metal tubes used in nuclear power applications. Furthermore, these solutions are quite mathematically complex and arduous to implement. In this work, the mainstream flow through a porous polymer membrane tube is examined and a method for calculating the through-membrane flow rate and axial pressure drop is presented. Two membrane tubes are tested experimentally, and a simple set …

5-Axis Tool Path Generation With Collision Detection For Finish Machining Of Freeform Surfaces, Jomy Francis

Masters Theses

"Research in the field of Tool path generation for freeform surfaces has been done intensively in the past. However, the main challenge that still exists is the computational efficiency related to the tool path generation. Tool path generation for freeform surface involves instantaneous calculation of new tool orientations which does not collide with the neighboring surfaces. Since the collision check of tool and neighboring surface is done repetitively at every instant of the tool, the calculations at every instant are to be computationally as easy as possible.

This thesis is composed of one paper. Paper I presents a novel extension …

Ultrasonic Communications System For Health Monitoring Of Hydrokinetic Turbine Blades, Andrew James Heckman

Masters Theses

"A health monitoring approach is investigated for hydrokinetic turbine blade applications. In-service monitoring is critical due to the difficult environment for blade inspection and the cost of inspection downtime. Composite blade designs provide a medium for embedding sensors into the blades for in-situ health monitoring. The major challenge with in-situ health monitoring is transmission of sensor signals from the remote rotating reference frame of the blade to the system monitoring station. In the presented work, a novel system for relaying in-situ blade health measurements in hydrokinetic systems is described and demonstrated. An ultrasonic communication system is used to transmit health …

Large-Eddy Simulation Of Axially-Rotating, Turbulent Pipe And Particle-Laden Swirling Jet Flows, Nicolas D. Castro

Mechanical & Aerospace Engineering Theses & Dissertations

The flows of fully-developed turbulent rotating pipe and particle-laden swirling jet emitted from the pipe into open quiescent atmosphere are investigated numerically using Large-Eddy Simulation (LES). Simulations are performed at various rotation rates and Reynolds numbers, based on bulk velocity and pipe diameter, of 5.3x103, 12x103, and 24x103, respectively. Time-averaged LES results are compared with experimental and simulation data from previous studies. Pipe flow results confirm observations in previous studies, such as the deformation of the turbulent mean axial velocity profile towards the laminar Poiseuille-profile, with increased rotation. The Reynolds stress anisotropy tensor shows a redistribution due to pipe rotation. …

Transient Growth And Instability Control Using Iteration-Varying Filter Ilc In Flexible Dual Flywheel System, Tong Mu

Masters Theses

"In the field of precision motion control, many industrial systems have flexible modes. This is especially true for very high performance nanopositioning systems where traditional bearing systems are replaced with flexible structures in order to eliminate sliding friction. The precision motion control is difficult in flexible systems because the rapid phase transition around the resonant frequency must be accurately modeled in order to actively control the resonant motion. In order to experimentally study the effectiveness of various control algorithms on flexible systems, a dual-flywheel flexible system is constructed. The mechatronics system design strategy is presented in this thesis. The control …

On The Extraction Of Volatiles From Lunar Regolith Using Solar Power, Jorge Alberto Frias

Open Access Theses & Dissertations

Recent lunar missions have confirmed the presence of water and miscellaneous volatiles within the craters of the Moon's South Pole. If harvested, these resources have the potential to provide an incredible budget saving to the human space exploration program by dropping the total mass that astronauts need to carry from the Earth. The area that develops these technologies is called In-Situ Resource Utilization (ISRU). ISRU allows reducing the payload, and consequently reduces the energy consumption and cost of space exploration. The present thesis investigates methods for the extraction of volatiles from regolith within the shadowed craters of the Moon using …

Development Of Thermoelectric Temperature Sensors, Jennifer Jazmin Kuchle Ituarte

Open Access Theses & Dissertations

Temperature measurements in power generation systems can provide useful information on the performance parameters of the units. This paper presents a conceptual measurement technique using a simulated thermoelectric loop (signal transmitter). The transmitter simulates the induced current and magnetic field emanating from the center of an n and p loop. The receiver used in this study is a Hall Effect sensing device which measures the magnetic flux density produced by the transmitter. Three experimental setups were designed and built for the measurements. The first setup used a pendulum to move a coil simulating a loop thermoelectric generator thereby creating a …

An Investigation On Cocombustion Behaviors Of Hydrothermally Treated Municipal Solid Waste With Coal Using A Drop-Tube Reactor, Liang Lu, Yuqi Jin, Masato R. Nakamura, Marco J. Castaldi, Kunio Yoshikawa

Publications and Research

This work aims at demonstrating the feasibility of replacing Indonesian coal (INC) with hydrothermally treated municipal solid waste (MSWH) in cocombustion with high ash Indian coal (IC). The combustion efficiencies and emissions (CO, NO) of MSWH, INC and their blends with IC for a series of tests performed under a range of temperatures and air conditions were tested in a drop- tube reactor (DTR). The results showed the following. The combustion efficiency of IC was increased by blending both MSWH and INC and CO emission was reduced with increasing temperature. For NO emission, the blending of MSWH led to the …

An Experimental Investigation On Lox/Lch4 Reaction Control Thrusters, Arturo Acosta-Zamora

Open Access Theses & Dissertations

This work describes the development and preliminary testing of a thrust measurement system, in combination with a propellant feed and automation controls systems to test the performance of 8.9 to 35.6 N (2 to 8 lbf) LOX/Methane reaction control thrusters. LOX/LCH4 has come to be the main focus of next generation "green" propellants for future space exploration. As there is limited experience with this propellant combination, an effort is being conducted to research performance of rockets using these propellants. The development of a thrust measurement, propellant feed, and automation controls systems is necessary for proper testing and qualification of thruster …

Combustion And Compaction Of Lunar Regolith/Magnesium Mixtures, Armando Delgado

Open Access Theses & Dissertations

Feasible techniques that require low energy consumption and reduced costs are of vital importance to enable humans to explore and occupy space. In-Situ Resource Utilization (ISRU) is the branch in the Human Exploration Technology that studies the production of consumables and materials using indigenous lunar and planetary resources. ISRU represents an enabling opportunity for establishing long lasting human exploration missions. Construction materials produced in-situ are of special interest because of the high payload they represent when launching them from Earth. The in-situ production of construction materials that requires low energy input would be advantageous due to the limited energy in …

Development Of The Control And Ignition Systems On A High Pressure Gas Turbine Combustor, Carlos Alejandro Valdez

Open Access Theses & Dissertations

The ignition and control systems of a laboratory scale high-pressure gas turbine combustor were developed in the present work. This work provides a detailed description of the design, development and testing of the remote control system developed for a High Pressure Gas Turbine Combustor (HPTC).

The combustor has the capability to operate at pressures up to 1.5 MPa and temperatures up to 2400 K. It is also designed for a maximum air and fuel flow rates of 81.93 g/s and 35.77 g/s respectively. The fuel used will be CH4 for the early experiments but it is designed to operate using …

Comparison Study Between Fem And Sem For Wave Propagation Models Applied To Solids, Shaddy Roberto Castillo Ponton

Open Access Theses & Dissertations

Wave propagation is a field whose application has spread across many disciplines. In the field of structural engineering, wave propagation methods have focused their attention specifically in the area of structural health monitoring and active control of vibrations and noise. Likewise, the development of new methods and their application have been successful in the area of material science with a special emphasis on the field of structural integrity evaluation of anisotropic and inhomogeneous structures (laminated composite structures). The current available analysis tools are inadequate to handle the modeling of complex structures. One-dimensional wave propagation problems in solids are still a …

Development Of A Multi-Material, Multi-Technology Fdm System For Process Improvement Experimentation, David Espalin

Open Access Theses & Dissertations

Over the last three decades, developments within the area of Additive Manufacturing (AM) have resulted in novel technologies capable of producing highly customized, complex part geometries in a fraction of the lead time required by traditional manufacturing methods (e.g., injection molding, metal casting). In particular, fused deposition modeling (FDM), a material extrusion AM process, can produce parts using production-grade thermoplastics like acrylonitrile butadiene styrene, polycarbonate, and polyetherimide. Additionally, non-commercial materials (e.g., polycaprolactone, ceramic loaded polymers, carbon nanotube loaded polymers) have been processed using FDM in part to demonstrate the potential diversity in material selection.

Recently, a myriad of personal 3D …

Electrical Characterization Of Microcrystalline Lifepo4 For Application In Lithium Ion Batteries, Sukhdeep Amarjeet Labana

Open Access Theses & Dissertations

Electrical Characterization of Microcrystalline LiFePO4 for application in lithium ion batteries. Mainly, to study about the electrical properties of Lithium Iron Phosphate as a cathode material to increase its Electrical consumption.

Low Energy Disruption Of Lipid Containing Biomass, Joaquin Rodriguez

Open Access Theses & Dissertations

Lipid containing biomass from microalgae has received recent research interest as a renewable and sustainable feedstock for biofuel production. Algae is known to offer as much as 30 times the energy density than corn based ethanol, the current world standard for biomass based liquid transportation fuels. The development of large scale systems and methods of extracting lipids from microalgae is still in the early stages of development and significant increases in efficiency and reduction in costs are necessary to substantiate algae as a feasible alternative source of fuel. Traditional conversion of algae feedstock into a refineable feedstock for biofuel can …

Control Of A Robotic Prototype Multi-Axis Synergistic System, Julio A. Torres

Open Access Theses & Dissertations

Balance is an ability that every person has and uses in normal daily life, to walk, run, stand, dance, etc. However, there are people who suffer a kind of balance impairment. The Computerized Dynamic Posturography (CDP) is technique in balance rehabilitation, where the patient is asked to stand on a moving platform that is equipped with sensors that measure how well you maintain your balance. In this thesis, a new CDP mechatronic system, the Multi-Axis Synergistic System (MASS), for balance assessment is being developed.

As a first stage and as the objective of this research work the transferable control algorithm …

Technical Feasibility Of Storage On Large Dish Stirling Systems, Charles E. Andraka, K Scott Rawlinson, Nathan P. Siegel

Faculty Journal Articles

Dish-Stirling systems have been demonstrated to provide high-efficiency solar-only electrical generation, holding the world record at 31.25%. This high efficiency results in a system with a high possibility of meeting the DOE SunShot goal of $0.06/kWh. Current dish-Stirling systems do not incorporate thermal storage. For the next generation of non-intermittent and cost-competitive solar power plants, we propose a thermal energy storage system that combines latent (phase-change) energy transport and latent energy storage in order to match the isothermal input requirements of Stirling engines while also maximizing the exergetic efficiency of the entire system. This report takes an initial look at …

Implementation And Assessment Of A Virtual Reality Experiment In The Undergraduate Themo-Fluids Laboratory, Sushil Chaturvedi, Jaewan Yoon, Rick Mckenzie, Petros J. Katsioloudis, Hector M. Garcia, Shuo Ren

Mechanical & Aerospace Engineering Faculty Publications

Results are presented from an NSF supported project that is geared towards advancing the development and use of virtual reality (VR) laboratories, designed to emulate the learning environment of physical laboratories. As part of this project, an experiment in the undergraduate thermo-fluids laboratory course titled "Jet Impact Force" was transformed into a 3-D virtual reality experiment using the widely used MAYA R and VIRTOOLS R software. In order to facilitate students' interactions with the newly created 3-D interactive, immersive and stereoscopic virtual laboratory environment, the human computer interfaces (HCI) were programmed and incorporated in the simulation software. Two immersion levels …

Extending Origami Technique To Fold Forming Of Sheet Metal Products, Ala Qattawi

All Dissertations

This dissertation presents a scientific based approach for the analysis of folded sheet metal products. Such analysis initializes the examination in terms of topological exploration using set of graph modeling and traversal algorithms. The geometrical validity and optimization are followed by utilizing boundary representation and overlapping detection during a geometrical analysis stage, in this phase the optimization metrics are established to evaluate the unfolded sheet metal design in terms of its manufacturability and cost parameters, such as nesting efficiency, total welding cost, bend lines orientation, and maximum part extent, which aides in handling purposes. The proposed approach evaluates the design …