Engineering Commons^™

Experimental Investigation Of Liquid Height Estimation And Simulation Verification Of Bolt Tension Quantification Using Surface Acoustic Waves, Hani Alhazmi

USF Tampa Graduate Theses and Dissertations

In this dissertation, two separate applications that are related to surface acoustic waves in a solid media are presented. The first study concerns simulating and validating an experimentally study for quantifying the bolt tension in the bolted joints using the surface acoustic wave. The second study experimentally investigates measuring the level of a liquid existing on a solid surface via surface acoustic waves and exploring the effect of liquid existence on the propagation of surface acoustic waves over the solid surface.

Quantifying bolt tension and ensuring that bolts are appropriately tightened for large-scale civil infrastructures are crucial. This study investigates …

Roboat - Rescue Operations Bot Operating In All Terrains, Akshay Gulhane

USF Tampa Graduate Theses and Dissertations

Natural calamities are on a rise with each passing year. Disasters like floods and fire take many lives all around the world, especially in remote areas or less developed countries. One such incident was the Kerala Floods in India where rescue services had difficulty reaching to all the people on time since a huge landmass (more than 9 districts) was flooded and hence villagers or other people risked their lives to save others in danger without proper safety equipment. Amazon Rainforest Fires was another example for a major destruction of an ecosystem. The main reason for lack of facilities in …

Control Of A Human Arm Robotic Unit Using Augmented Reality And Optimized Kinematics, Carlo Canezo

USF Tampa Graduate Theses and Dissertations

There are more than 350000 amputees in the US who suffer loss of functionality in their daily living activities, and roughly 100000 of them are upper arm amputees. Many of these amputees use prostheses to compensate part of their lost arm function, including power prostheses. Research on 6-7 degree of freedom powered prostheses is still relatively new, and most commercially available powered prostheses are typically limited to 1 to 3 degrees of freedom. Due to the myriad of possible options for various powered protheses from different manufacturers, each configuration is governed by a distinct control scheme typically specific to the …

Swimming Of Pelagic Snails: Kinematics And Fluid Dynamics, Ferhat Karakas

USF Tampa Graduate Theses and Dissertations

Pteropods (also known as sea butterflies or sea angels), are holoplanktonic marine snails which swim by flapping a pair of extremely flexible wings. The wings are modified from the molluscan foot and the wing motions are supported by the fluid pressure without any rigid support. Sea angels (gymnosome pteropods) are completely naked; in contrast, sea butterflies (thecosome pteropods) have negatively buoyant aragonite shells which vary in geometry and size among different species. Pteropods are seasonally abundant in the ocean, and an important food source for the other zooplanktons, fishes, and whales. Though studies have been conducted regarding their biology, ecology, …

Simulation And Verification Of Phase Change Materials For Thermal Energy Storage, Marwan Mosubah Belaed

USF Tampa Graduate Theses and Dissertations

Greenhouse gas (GHG) emissions have a global impact on world economies and the ecosystem. Scientific assessment of GHG emissions is an issue that requires immediate action from key decision-makers and influencers. A comprehensive review of the impact of climate change and its dire consequences on daily life is illustrated in this dissertation. The most common technique to lower GHG emissions in the atmosphere is by switching GHG emission sources to zero-emission sources such as solar energy, wind energy, bioenergy, and geothermal power. Recently, all these technologies have made significant progress in lowering capital operation costs and their cycle efficiencies. This …

Laser Micropatterning Effects On Corrosion Resistance Of Pure Magnesium Surfaces, Yahya Efe Yayoglu

USF Tampa Graduate Theses and Dissertations

Magnesium and its alloys are good candidates to manufacture medical implants. They have excellent biocompatibility and because they biodegrade secondary surgical operation to remove the implant could be eliminated. However, in aqueous environments, magnesium alloys rapidly corrode, resulting in premature degradation of the implant along with biologically intolerable hydrogen gas generation. In literature, there are multiple studies focused on creating water repelling hydrophobic magnesium surfaces in order to decrease corrosion rates. Hydrophobic properties can be achieved by creation of a roughness profile on an initially smooth surface combined with a treatment that reduces the free surface energy. In theory, hydrophobic …

Investigation Of Navigation Systems For Size, Cost, And Mass Constrained Satellites, Omar Awad

USF Tampa Graduate Theses and Dissertations

The feasibility of using radically inexpensive micro-electromechanical system (MEMS) technology for navigation of a nanosatellite is investigated with a focus on attitude estimation. Typically, larger satellites are equipped with star cameras, sun sensors, or Earth horizon sensors for attitude estimation. These sensors can provide very accurate attitude measurements. A nanosatellite is highly size, power, and cost constrained and cannot readily accommodate these sensors. Our mission is to design, build, and operate a radically inexpensive nanosatellite system. While there is no consensus on what constitutes a "radically inexpensive" satellite, our goal is a maximum cost of $10,000 per unit. This precludes …

Manipulation And Patterning Of Mammalian Cells Using Vibrations And Acoustic Forces, Joel Cooper

USF Tampa Graduate Theses and Dissertations

Recently, there has been a surge in researchers and scientists investigating different methods which move, manipulate, and pattern biological cells. Multiple different mechanisms can be used for cellular manipulation, microfluidics, biochemical queues, and even optics, just to name a few. However, all techniques have their downsides. A majority of these methods require expensive equipment or reagents and can only manipulate a small number of cells at a time.

Some of the most common cell manipulation devices utilize acoustic pressure waves to move the cells to desired locations. Currently, it is unknown what level of force from these types of devices …

Stable Adaptive Control Systems In The Presence Of Unmodeled And Actuator Dynamics, Kadriye Merve Dogan

USF Tampa Graduate Theses and Dissertations

In adaptive control of physical systems, it is well-known that the presence of actuator and/or unmodeled dynamics in feedback loops can yield to unstable closed-loop system trajectories. Motivated by this standpoint, this dissertation presents novel model reference and distributed adaptive control architectures with stability and performance guarantees for uncertain sole and multiagent dynamical systems with unmodeled and/or actuator dynamics.

Specifically, model reference and distributed adaptive control architectures are powerful theoretical tools for both sole and multiagent systems, where they have the capability to suppress the effect of exogenous disturbances and system uncertainties for achieving a desired level of closed-loop system …

Shallow Water Seafloor Geodesy: Gps On An Anchored Spar Buoy, Surui Xie

USF Tampa Graduate Theses and Dissertations

Measuring seafloor motion in shallow coastal water is challenging due to strong and highly variable oceanographic effects. Such measurements are potentially useful for monitoring near-shore coastal subsidence, subsidence due to petroleum withdrawal, strain accumulation/release processes in marine shelves and submerged volcanoes, and certain fresh water applications, such as volcano deformation in caldera-hosted lakes. I participated in a project to develop a seafloor geodetic system for this environment based on an anchored spar buoy topped by high precision GPS. Orientation of the buoy is measured using a digital compass that provides heading, pitch, and roll information. The combined orientation and GPS …