Matching Items (53)
Description
This study regarding a proposed variable stiffness structure will focus on structure geometry as a proof of concept attempt to develop a new design for energy dispersion. The structure was designed such that as a greater force is experienced, more of the structure comes into contact with itself making the structure stiffer, hence the name variable stiffness structure. This variable stiffness will provide softer structure properties under small loads and stiffer properties under larger loads. This allows an impact to be absorbed by the structure under low loads without compromising structure stiffness that provides protection at higher loads. Intended function of this structure is an intermediate layer in protective gear such as helmets for military and athletic applications, athletic padding, or everyday applications such as the soles of shoes or medical crutches. Proof of concept for the variable stiffness structures was successful as validated by the observance of three distinct slopes in the load vs. compression data reflecting the desired three contact regions on four different structures tested. Structures that performed as intended were also more successful at dispersing energy as calculated by the integral of the load vs. compression curves. Observed trends include desirable increased contact spacing and geometry thickness for a 2:1 height to width structure ratio. Since these results are on the limits of the optimization conditions, additional testing will be required to determine true optimal design. Energy dispersion trends would suggest that structure 135 was the most successful structure at dissipating energy. While this structure was successful, (1.42 J of energy dissipated in the variable stiffness region) structure 313 outperformed it by nearly 1 J (2.25 J average). Upon examination of testing footage, structure 313 displayed the unique quality of engaging multiple contact points in each contact region. This suggests that the number of contact points may be the unobserved variable that will further the variable stiffness structure design for improved energy dispersion in future iterations. With further development, the variable stiffness structures could be an influential means of energy dispersion for utilization in a wide variety of applications.
ContributorsCampbell, Ryan Gregory (Author) / LaBelle, Jeffrey (Thesis director) / Lathers, Steven (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
In order to address infant respiratory distress syndrome, this study attempts to develop and characterize a textile strain gauge fabricated with stainless steel, wool, elastic, and tencel. Faire Isle knitted patterns are investigated in order to create channels of conductivity for a linear sensor. The effect linear yarn density on linearity and sensitivity and hysteresis of the sensors is also investigated for sensor optimization. It was found that there was a significant difference between the patterned and non-patterned samples. The patterned sensors were found to have a lower range of resistance than the non-patterned sensors and a smaller average standard of deviation between measurements. The 7 tension, lower linear yarn density, elastic patterned sample was the only sample to not exhibit hysteresis after three trials as well as have a linear range from 11.5cm to 13cm where the sensor behaves in accordance with a linear transfer function.
ContributorsBrown, Shannon (Co-author) / Irimata, Lisa (Co-author) / LaBelle, Jeffrey (Thesis director) / Hanson, Erika (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2015-05
DescriptionMy main goal for my thesis is in conjunction with the research I started in the summer of 2010 regarding the creation of a TBI continuous-time sensor. Such goals include: characterizing the proteins in sensing targets while immobilized, while free in solution, and while in free solution in the blood.
ContributorsHaselwood, Brittney (Author) / LaBelle, Jeffrey (Thesis director) / Pizziconi, Vincent (Committee member) / Cook, Curtiss (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2011-12
Description
The Honors Thesis involved the use of vertically-aligned, piezoelectric nanowire sensor arrays configured by Dr. Henry A. Sodano and Dr. Aneesh Koka from the University of Florida, in order to acquire acceleration data. Originally, the project was focused on interfacing and calibrating the barium titanate (BaTio3) sensors to measure wall shear stress, a fluid dynamic characteristic. In order to gain an understanding of these novel piezoelectric sensors, the experiments performed by Sodano and Koka were to be investigated, replicated, and results reproduced. After initial trial phases, signals failed to be consistently measured from the sensors and the project's emphasis was re-defined. The outlined goals were 1) to re-design the initial system used for signal acquisition, 2) test the improved signal acquisition system, 3) successfully measure output signals from the BaTiO3 nanowire sensors, and 4) determine the cause for inconsistent signal measurements from the piezoelectric nanawire sensors. Following a detailed review of the previous experimental procedures and the initial signal acquisition system, an improved acquisition system was designed and its expected behavior was tested and verified. Despite the introduction of the improved acquisition system, voltage outputs were unable to be measured as a function of shaker table acceleration. It was impossible to verify the effect of the improved signal acquisition system on the measured BaTiO3 nanowire sensor output. Based on an analysis of data collected using a commercial 3-axis acceleromoeter, it is hypothesized that the BaTiO3 nanowire sensors were broken after the first experimental trial due to an excessively applied force from an external source (i.e. shaker table, improper handling during experimentation, and/or improper handling during transportation).
ContributorsThomas, Jonah (Author) / Frakes, David (Thesis director) / LaBelle, Jeffrey (Contributor) / Barrett, The Honors College (Contributor)
Created2014-05
Description
The purpose of this project was to examine the viability of protein biomarkers in pre-symptomatic detection of lung cancer. Regular screening has been shown to vastly improve patient survival outcome. Lung cancer currently has the highest occurrence and mortality of all cancers and so a means of screening would be highly beneficial. In this research, the biomarker neuron-specific enolase (Enolase-2, eno2), a marker of small-cell lung cancer, was detected at varying concentrations using electrochemical impedance spectroscopy in order to develop a mathematical model of predicting protein expression based on a measured impedance value at a determined optimum frequency. The extent of protein expression would indicate the possibility of the patient having small-cell lung cancer. The optimum frequency was found to be 459 Hz, and the mathematical model to determine eno2 concentration based on impedance was found to be y = 40.246x + 719.5 with an R2 value of 0.82237. These results suggest that this approach could provide an option for the development of small-cell lung cancer screening utilizing electrochemical technology.
ContributorsEvans, William Ian (Author) / LaBelle, Jeffrey (Thesis director) / Spano, Mark (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
This project aims to use the shape memory alloy nitinol as the basis for a biomimetic actuator. These actuators are designed to mimic the behavior of organic muscles for use in prosthetic and robotic devices. Actuator characterization included in the project examines the force output,electrical properties, and other variables relevant to actuator design.
ContributorsNoe, Cameron Scott (Author) / LaBelle, Jeffrey (Thesis director) / Santello, Marco (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Acetaminophen, commonly found in Tylenol and other over the counter (OTC) pharmaceuticals, was electrochemically characterized on custom made, flexible, screen printed electrodes (SPEs) to serve as a model target pharmaceutical found in flowing water lines. Carbon, silver/silver chloride, and insulator paste inks were printed onto polyethylene naphthalateolyester (PEN) using custom made stencils for a 4x1 array of 3-electrode electrochemical cells. Cyclic voltammetry was performed to find the electrical potential corresponding to the greatest current response and the experiments were conducted using amperometric current-time mode (AMP*i-t). The physical limitations of SPEs as well as the detection limitations of the target, such as pH and temperature were tested. A concentration gradient of the target was fitted with a linear curve (R2 0.99), and a lower limit of detection of 14.5 μM. It was also found that both pH and temperature affect the current produced by acetaminophen at a fixed concentration, and that the sensors can detect target in a continuous flow. A flow apparatus consisting of an inlet and effluent pipe served as the flow model into which a rolled up flexible electrode array was inserted. The broader goal of this research is to develop a highly sensitive electrode array on flexible substrates which can detect multiple targets simultaneously. Acetaminophen was chosen due to its electro-active properties and its presence in most public water lines in the United States.
ContributorsMaxwell, Stephanie Ann (Author) / LaBelle, Jeffrey (Thesis director) / Allee, David (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
This paper summarizes the [1] ideas behind, [2] needs, [3] development, and [4] testing of 3D-printed sensor-stents known as Stentzors. This sensor was successfully developed entirely from scratch, tested, and was found to have an output of 3.2*10-6 volts per RMS pressure in pascals. This paper also recommends further work to render the Stentzor deployable in live subjects, including [1] further design optimization, [2] electrical isolation, [3] wireless data transmission, and [4] testing for aneurysm prevention.
ContributorsMeidinger, Aaron Michael (Author) / LaBelle, Jeffrey (Thesis director) / Frakes, David (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2014-05
Description
Cardiopulmonary resuscitation (CPR) is an emergency course of action developed to sustain oxygenated blood flow in persons suffering from cardiac arrest by manually compressing the heart in the chest and providing rescue ventilations. The best-selling CPR manikins, an integral part of training, lack biofidelic characteristics in appearance, feel, and response, and as a result, the rescuer's learning experience suffers. The objective of this thesis was to test the compressibility properties of different foams and thermoplastics in order to determine which material would most accurately imitate a human chest response. The results suggested that styrene-ethylene/butylene-styrene (SEBS) was the best choice, because its increasing stiffness under increasing compression was characteristic of a human chest cavity. Further testing must be done to determine the best composition of SEBS, analyze its response under cyclic compressions, and improve its durability.
ContributorsWalsh, Alex Bradley (Author) / LaBelle, Jeffrey (Thesis director) / Pizziconi, Vincent (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Growing concern over health risks associated with environmental contaminants has prompted an increase in the search for effective detection methods. The available options provide acceptable sensitivity and specificity, but with high purchase and maintenance costs. Herein, a low-cost, portable environmental contaminant sensor was developed using electrochemical techniques and an efficient hydrogel capture mechanism. The sensor operates with high sensitivity and maintains specificity without the added requirement of extensive electrode modification. Rather, specificity is obtained by choosing specific potential regions in which individual contaminants show reduction or oxidation activity. A calibration curve was generated showing the utility of the sensor in detecting gas compounds reliably in reference to a current state of the art sensor. Reusability of the sensor was also demonstrated with a cyclic exposure test in which response reversibility was observed. As such, the investigated sensor shows great promise as a replacement technology in the current environmental contaminant detector industry.
ContributorsMarch, Michael Stephen (Author) / LaBelle, Jeffrey (Thesis director) / Caplan, Michael (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05