Biomedical Engineering and Bioengineering Commons^™

Dynamic Mutual Capacitive Sensor For Human Interactions., Jonathan William Huber

Doctoral Dissertations

This dissertation introduces the novel concept of removing the ground conductive plate by utilizing body capacitance as the ground in the capacitive sensor, whereby circuit pressure sensing can occur with only one plate and one dielectric. Additionally, body capacitance sensing was limited to a binary touch-no-touch output, whereas the method presented here can sense various applied pressures. The resulting circuit acts as an antenna that receives local capacitance signals from a human interaction.

The advantage of this design is that it allows for both proximity sensing and pressure sensing (once the body part is touching the dielectric material). This setup …

Quaternionic Attitude Estimation With Inertial Measuring Unit For Robotic And Human Body Motion Tracking Using Sequential Monte Carlo Methods With Hyper-Dimensional Spherical Distributions, Gary To

Doctoral Dissertations

This dissertation examined the inertial tracking technology for robotics and human tracking applications. This is a multi-discipline research that builds on the embedded system engineering, Bayesian estimation theory, software engineering, directional statistics, and biomedical engineering.

A discussion of the orientation tracking representations and fundamentals of attitude estimation are presented briefly to outline the some of the issues in each approach. In addition, a discussion regarding to inertial tracking sensors gives an insight to the basic science and limitations in each of the sensing components.

An initial experiment was conducted with existing inertial tracker to study the feasibility of using this …

Computer Modeling And Signal Analysis Of Cardiovascular Physiology, Henian Xia

Doctoral Dissertations

This dissertation aims to study cardiovascular physiology from the cellular level to the whole heart level to the body level using numerical approaches.

A mathematical model was developed to describe electromechanical interaction in the heart. The model integrates cardio-electrophysiology and cardiac mechanics through excitation-induced contraction and deformation-induced currents. A finite element based parallel simulation scheme was developed to investigate coupled electrical and mechanical functions. The developed model and numerical scheme were utilized to study cardiovascular dynamics at cellular, tissue and organ levels. The influence of ion channel blockade on cardiac alternans was investigated. It was found that the channel blocker …

Modulation Of Bone And Nerve Cell Behavior Using Biodegradable Polymer Networks, Lei Cai

Doctoral Dissertations

This dissertation presents novel biodegradable and photo-crosslinkable building blocks to achieve polymer networks with controlled surface chemistry, stiffness, and topographical features for investigating cell-material interactions and targeting hard and soft tissue engineering applications. Chapter I reviews the recent progress in polymeric gel systems and how their physical properties can be tailored to regulate cell functions and satisfy the clinical needs. Chapter II presents a facile method to synthesize photo-crosslinkable poly(epsilon-caprolactone) acrylates (PCLAs) and reveal tunable cell responses to photo-crosslinked PCLAs. Chapter III investigates the mechanism of colorization in preparing crosslinkable polymers by reacting hydroxyl-containing polymers with unsaturated anhydrides or acyl …

Vision-Based Robot Control In The Context Of Human-Machine Interactions, Andrzej Nycz

Doctoral Dissertations

This research has explored motion control based on visual servoing – in the context of complex human-machine interactions and operations in realistic environments. Two classes of intelligent robotic systems were studied in this context: operator assistance with a high dexterity telerobotic manipulator performing remote tooling-centric tasks, and a bio-robot for X-ray imaging of lower extremity human skeletal joints during natural walking. The combination of human-machine interactions and practical application scenarios has led to the following fundamental contributions: 1) exploration and evaluation of a new concept of acquiring fluoroscope images of musculoskeletal features of interest during natural human motion, 2) creation …

A Novel Imaging System For Automatic Real-Time 3d Patient-Specific Knee Model Reconstruction Using Ultrasound Rf Data, Rimon Adel Messiha Tadross

Doctoral Dissertations

This dissertation introduces a novel imaging method and system for automatic real-time 3D patient-specific knee model reconstruction using ultrasound RF data. The developed method uses ultrasound to transcutaneously digitize a point cloud representing the bone’s surface. This point cloud is then used to reconstruct 3D bone model using deformable models method.

In this work, three systems were developed for 3D knee bone model reconstruction using ultrasound RF data. The first system uses tracked single-element ultrasound transducer, and was experimented on 12 knee phantoms. An average reconstruction accuracy of 0.98 mm was obtained. The second system was developed using an ultrasound …

Development And Experimental Analysis Of Wireless High Accuracy Ultra-Wideband Localization Systems For Indoor Medical Applications, Michael Joseph Kuhn

Doctoral Dissertations

This dissertation addresses several interesting and relevant problems in the field of wireless technologies applied to medical applications and specifically problems related to ultra-wideband high accuracy localization for use in the operating room. This research is cross disciplinary in nature and fundamentally builds upon microwave engineering, software engineering, systems engineering, and biomedical engineering. A good portion of this work has been published in peer reviewed microwave engineering and biomedical engineering conferences and journals. Wireless technologies in medicine are discussed with focus on ultra-wideband positioning in orthopedic surgical navigation. Characterization of the operating room as a medium for ultra-wideband signal transmission …

Characteristics And Functionalities Of Natural And Bioinspired Nanomaterials, Lijin Xia

Doctoral Dissertations

Green nanoscience is a rapidly emerging field that aims to achieve the maximum performance and benefits from nanotechnology, while minimizing the impact on the environment. In this study, several methods for the green nanomanufacturing of biomedically important nanomaterials, specifically through the use of natural plants, have been extensively investigated. It was found that natural nanomaterials are inherent within plants, and can be further manipulated for potential biomedical applications. In addition, the metabolites and reductive capacity of plant extracts can be used to synthesize metallic nanoparticles with advantages over semi-conductor based nanomaterials. Nanoparticles were found to exist in the extracts produced …

Dynamics, Electromyography And Vibroarthrography As Non-Invasive Diagnostic Tools: Investigation Of The Patellofemoral Joint, Filip Leszko

Doctoral Dissertations

The knee joint plays an essential role in the human musculoskeletal system. It has evolved to withstand extreme loading conditions, while providing almost frictionless joint movement. However, its performance may be disrupted by disease, anatomical deformities, soft tissue imbalance or injury. Knee disorders are often puzzling, and accurate diagnosis may be challenging. Current evaluation approach is usually limited to a detailed interview with the patient, careful physical examination and radiographic imaging. The X-ray screening may reveal bone degeneration, but does not carry sufficient information of the soft tissue conditions. More advanced imaging tools such as MRI or CT are available, …

Polymeric Microsensors For Intraoperative Contact Pressure Measurement, Emily R. Pritchard

Doctoral Dissertations

Biocompatible sensors have been demonstrated using traditional microfabrication techniques modified for polymer substrates and utilize only materials suitable for implantation or bodily contact. Sensor arrays for the measurement of the load condition of polyethylene spacers in the total knee arthroplasty (TKA) prosthesis have been developed. Arrays of capacitive sensors are used to determine the three-dimensional strain within the polyethylene prosthesis component. Data from these sensors can be used to give researchers a better understanding of component motion, loading, and wear phenomena for a large range of activities. This dissertation demonstrates both analytically and experimentally the fabrication of these sensor arrays …

Development Of A Computational Model To Predict The In Vivo Contact Mechanics Of Modern Total Knee Arthroplasty, Adrija Sharma

Doctoral Dissertations

This dissertation focuses on the development of a computationally efficient and fast method that incorporates the kinematics obtained from fluoroscopy and extends it to the prediction of the in-vivo contact mechanics at the femoro-tibial articulation in modern knee implants for the deep knee bend activity. In this endeavor, this dissertation deals with the use of an inverse dynamic rigid body model characterizing the slip and roll behavior observed in the femoro-polyethylene articulation and a coupled deformation model where the polyethylene in knee implants are modeled as hexahedral discrete element networks. The performance of this method is tested by comparing force …

The Future Of The Operating Room: Surgical Preplanning And Navigation Using High Accuracy Ultra-Wideband Positioning And Advanced Bone Measurement, Brandon C. Merkl

Doctoral Dissertations

This dissertation embodies the diversity and creativity of my research, of which much has been peer-reviewed, published in archival quality journals, and presented nationally and internationally. Portions of the work described herein have been published in the fields of image processing, forensic anthropology, physical anthropology, biomedical engineering, clinical orthopedics, and microwave engineering.

The problem studied is primarily that of developing the tools and technologies for a next-generation surgical navigation system. The discussion focuses on the underlying technologies of a novel microwave positioning subsystem and a bone analysis subsystem. The methodologies behind each of these technologies are presented in the context …

Flow And Transport In Unsaturated Porous Media: Fractal Modeling, Analytical Solutions And Experimentation, Abdullah Cihan

Doctoral Dissertations

This dissertation consists of five parts, each describing a specific topic of unsaturated flow and transport. The first three parts describe the development of soil hydraulic function models with the effects of partial drainage by using fractal and probabilistic approaches. During drainage of a porous medium, both the pore size distribution and the connectivity of pores determine the drained pore volume as function of suction. New analytical expressions were presented for the water retention (part 1), intrinsic permeability (part 2), and relative permeability (part 3) functions. Predictions based on the analytical models are compared with estimates of the intrinsic permeability …

Mems Capacitive Strain Sensing Elements For Integrated Total Knee Arthroplasty Prosthesis Monitoring, Boyd Mccutchen Evans Iii

Doctoral Dissertations

Measuring the in vivo load state of Total Knee Arthroplasty (TKA) components is required to understand the structural environment and wear characteristics of the devices. The ability to acquire this information gives tremendous insight into the mechanics of the joint replacement prosthesis. Data corresponding to normal loads, in-plane loads, shear loads, load center, contact area, and the rate of loading is needed to fully understand the kinematics and kinetics of the orthopedic implant. In this research, a novel sensing system has been developed which is capable of fully characterizing three-dimensional strain and stress at a single location.

Capacitance-based sensors were …

Theoretical Modeling And Experimental Validation Of In Vivo Mechanics For Subjects Having Variable Cervical Spine Conditions, Fei Liu

Doctoral Dissertations

The objective of this study was to use the state-of-art 3D-to-2D registration technologies including fluoroscopic, CT and MRI methods to analyze 2D and 3D in vivo kinematics of the whole cervical spine under variable conditions; and use inverse dynamic model based on Kane’s dynamics to predict their 2D and 3D in vivo interactive contact and muscular forces. Totally, forty patients (ten having normal cervical spines, ten having degenerative cervical spines, ten having anterior cervical decompression and fusion (ACDF), and ten having cervical artificial disc replacement (CADR)) were enrolled into 2D study and three patients (one having normal cervical spines, one …

Characterization Of A Biomimetic Calcium-Deficient Hydroxyapatite-Bacterial Cellulose Composite, Stacy Hutchens

Doctoral Dissertations

Bone is the second most implanted tissue next to blood causing approximately 2.2 million people to receive bone grafts each year. Developing safe synthetic bone grafts allows quick and safe restoration of bone function while avoiding the surgical risks associated with bone autografting (self donation), and risks of disease transmission and immunogenic response associated with allografts (bone donated from other humans) and xenografts (grafts derived from animal tissue). This dissertation entails the study and development of a novel potential synthetic bone graft consisting of a composite of calcium-deficient hydroxyapatite (CdHAP) biomimetically deposited in a bacterial cellulose (BC) hydrogel.

To determine …

Design And Evaluation Of A Non-Intrusive Corn Population Sensor, Haizhou Li

Doctoral Dissertations

Specific objectives of this study were to develop, prototype, and test a corn population sensor. Both intrusive mechanical and non-intrusive capacitive techniques have been used to develop the stalk population sensors in previous research. However, neither could generate consistent performance. The mechanical method required high maintenance and resulted in significant underestimations of stalk counts. The performance of capacitive systems was limited by inadequate sensing distance, especially at low stalk moisture levels.

In this research, the sensitivity of the capacitive sensor was optimized for corn stalks. This system utilized a single-sided capacitive sensor, Wien bridge oscillator, phase-locked loop, and an operational …

Modification And Evaluation Of Continuous Roll Prediction Model For Front Drive Mowers, Xinyan Wang

Doctoral Dissertations

The recently approved ASAE Standard S547 “Tip-Over Protective Structure (TOPS) for Front Wheel Drive Turf and Landscape Equipment” addressed a continuous roll prediction model for Roll-Over Protective Structure (ROPS) design. The existing model described in this Standard did not take into account the influence of the mower deck on the rollover behavior. In order to evaluate the accuracy of the original model, according to the ASAE S547 requirement, a 4.05 meters long and 3.42 meters wide slope of 35 degrees was constructed at the University of Tennessee. Lateral upset tests for Deere F925 front drive mower with regular and inverted …

A Distributed Control System For Priority-Based Site-Specific Irrigation, Fabio Rodrigues De Miranda

Doctoral Dissertations

Site-specific irrigation enables maximizing yields and water use efficiency for fields with variation in soil water availability. Distributed control for fixed irrigated systems, with controllers close to the sensors and actuators in the field, is easier to install and maintain, and less susceptible to damage by lightning strikes compared to centralized control, but is only economically viable with affordable, low-power controllers. A low cost, solar-powered, feedback irrigation controller for distributed control of fixed irrigation systems was developed and tested. The system used soil water potential measurements to control the amount of water applied to each specific zone of a field. …

Delineation Of Management Units For Site-Specific Irrigation.”, Carlos Wagner Oliveira

Doctoral Dissertations

Variability of soil properties in many fields is too great for a whole field to be effectively managed with a uniform application of irrigation water. Consequently, a decision must be made for irrigation management about which areas in the field should be treated differently or grouped. A decision-making framework was developed to determine whether site-specific irrigation management would be cost effective for selected fields. The framework is designed to find the best field layout in terms of water management, and tests the hypothesis that there is a particular field management layout that maximizes net return. As part of the framework, …

Molecular Characterization Of The T(4;9)12gso Mutation And Analysis Of The Associated Fitness, Skeletal, And Lymphoproliferative Phenotypes, Laura Ray Chittenden

Doctoral Dissertations

The t(4;9)(B3;E3.2)12Gso reciprocal translocation is an autosomal recessive mouse mutation involving chromosome 4, band B3 (Mmu4B3) and chromosome 9, band E3.2 (Mmu9E3.2). The most striking phenotype of the 12Gso homozygote involves axial skeleton deformities, resulting in significant shortening of body length, scoliosis, displaced hips and kinky tails. Homozygous animals are significantly smaller than normal littermates and frequently exhibit early lethality, as many of the mutants perish by 1 day postnatal, and many others do not survive the three weeks to weaning age. Homozygous 12Gso mice also develop an unusual bone marrow defect that closely resembles leukemia. The penetrance of the …

Comparative Gene Mapping In Baboon (Papio) Species, Kathleen Lou Moore Thiessen

Doctoral Dissertations

Gene mapping in nonhuman mammalian species is a field of increasing importance in man's efforts to understand genome organization, to develop animal models for human genetic diseases, and to investigate phylogenetic relationships and evolutionary mechanisms. The primates are of particular interest in these studies because of their morphological and physiological similarities to man. The availability and convenient size of the baboons (Papio species) make them the primates of choice for various areas of research having applications to man. The baboons also appear to have many chromosomal and genetic homologies to man as well as to the other primates, although …

X-Ray-Induced Specific-Locus Mutation Rates In Newborn And Young Mice, Paul Bruce Selby

Doctoral Dissertations

The specific-locus mutation frequency resulting from 300 R of acute X irradiation has been determined for the germ cells present in male mice at 0, 2, 4, 6, 8, 10, 14, 21, 28, and 35 days of age and also for female mice at 0 days of age, Sample size was much larger for the males irradiated on day 0 than for other age groups but in all groups it was large enough to insure that an extremely high rate would be noticed. At 35 days of age the testis is histologically similar to that of the adult. It was …