Biomechanical Engineering Commons^™

Surface Laser Texturing Of Cocrmo Alloys, Gabriel Dharwadker

Biomedical Engineering Undergraduate Honors Theses

Artificial orthopedic implants such as hip joints suffer from excessive wear due to excess friction between the polyethylene and cobalt-chromium-molybdenum surfaces of the device. This increase in friction causes a fraction of them to give out within ten years. Therefore, to minimize the probability of this happening, recent research has been conducted regarding laser surface texturing of the cobalt-chromium-molybdenum alloy components of artificial joints. These surface textures serve to mimic the native lubrication mechanisms of cartilage in natural joints, which, in a natural joint, lowers the friction. However, the production of these laser surface textures is still a field of …

Radiomic Features To Predict Overall Survival Time For Patients With Glioblastoma Brain Tumors Based On Machine Learning And Deep Learning Methods, Lina Chato

UNLV Theses, Dissertations, Professional Papers, and Capstones

Machine Learning (ML) methods including Deep Learning (DL) Methods have been employed in the medical field to improve diagnosis process and patient’s prognosis outcomes. Glioblastoma multiforme is an extremely aggressive Glioma brain tumor that has a poor survival rate. Understanding the behavior of the Glioblastoma brain tumor is still uncertain and some factors are still unrecognized. In fact, the tumor behavior is important to decide a proper treatment plan and to improve a patient’s health. The aim of this dissertation is to develop a Computer-Aided-Diagnosis system (CADiag) based on ML/DL methods to automatically estimate the Overall Survival Time (OST) for …

Development And Application Of 3d Kinematic Methodologies For Biomechanical Modelling In Adaptive Sports And Rehabilitation, Anne Marie Severyn

All Dissertations

Biomechanical analysis is widely used to assess human movement sciences, specifically using three-dimensional motion capture modelling. There are unprecedented opportunities to increase quantitative knowledge of rehabilitation and recreation for disadvantaged population groups. Specifically, 3D models and movement profiles for human gait analysis were generated with emphasis on post-stroke patients, with direct model translation to analyze equivalent measurements while horseback riding in use of the alternative form of rehabilitation, equine assisted activities and therapies (EAAT) or hippotherapy (HPOT). Significant improvements in gait symmetry and velocity were found within an inpatient rehabilitation setting for patients following a stroke, and the developed movement …

Atomic Force Microscopy Based Dna Sensing And Manipulation, Matthew Shubert

Mechanical Engineering Undergraduate Honors Theses

Sequencing DNA provides a positive impact for the biomedical community by understanding a wide variety of applications such as human genetics, disease, and pathogens. The reason the Arkansas Micro & Nano Systems lab is involved with research in DNA sequencing is due to the current, leading industry method. Nanopore sequencing was developed by Oxford Nanopore Technology in which its sequencing method separates double stranded DNA to electrically characterize individual nucleotides traveling through a charged nanopore. Unfortunately, nanopore sequencing uses biological materials that require a shelf life and drives high cost. Therefore, the Arkansas Micro & Nano Systems lab has developed …

Finite Element Model Of The Pediatric Hip Joint During The Barlow Maneuver, Christina M. Zlock

Doctoral Dissertations and Master's Theses

Developmental Dysplasia of the Hip is the dysplasia or dislocation of an unstable femoral head in the acetabulum of the pelvis. This is a result of an abnormal or underdeveloped growth of the acetabulum and triradiate cartilages and/or an out of place and uncentered femoral head in the acetabulum. This underdevelopment, if not diagnosed and treated at an early age, may lead to abnormal and pain and osteoarthritis later in life. A common step in diagnosis is to perform a physical examination of the hip, one method is the Barlow maneuver.

The aim of the project is to use healthy …

Design And Computational Validation Of A Shear Stress Bioreactor For Conditioning Vascular Tissue To Time-Varying Multidirectional Fluid Shear Stress, Rajeshwari Raja, Philippe Sucosky, Jason Shar

Symposium of Student Scholars

Design and Computational Validation of a Shear Stress Bioreactor for Conditioning Vascular Tissue to Time-Varying Multidirectional Fluid Shear Stress

Author: Rajeshwari Raja Mentor: Dr. Jason A. Shar Department of Mechanical Engineering Kennesaw State University 1100 South Marietta Pkwy SE, 30060

Altered biological environments and conditions, such as microgravity and pregnancy, can impact vascular blood flow and, in turn, generate fluid wall shear stress (WSS; frictional force generated on the tissue surface due to blood flow) abnormalities. These abnormalities are known to affect cardiovascular tissue biology and can be replicated experimentally using a cone-and-plate shear stress bioreactor. This device exposes tissue …

A Meshless Approach To Computational Pharmacokinetics, Anthony Matthew Khoury

Doctoral Dissertations and Master's Theses

The meshless method is an incredibly powerful technique for solving a variety of problems with unparalleled accuracy and efficiency. The pharmacokinetic problem of transdermal drug delivery (TDDD) is one such topic and is of significant complexity. The locally collocated meshless method (LCMM) is developed in solution to this topic. First, the meshless method is formulated to model this transport phenomenon and is then validated against an analytical solution of a pharmacokinetic problem set, to demonstrate this accuracy and efficiency. The analytical solution provides a locus by which convergence behavior are evaluated, demonstrating the super convergence of the locally collocated meshless …

The Optimal Relationship Between Actuator Stiffness And Actuation Timing For A Passive Ankle Exoskeleton: An Opensim Simulation, Cody Anderson, Hafizur Rahman, Sara Myers

UNO Student Research and Creative Activity Fair

Introduction

The passive ankle exoskeleton developed by Collins et al. (2015) reduced the metabolic cost of walking with an actuation-timing of ~16% of stance [1]; however, other actuation timings have not been extensively investigated. Therefore, the purpose of this study was to determine the optimal relationship between actuator-stiffness and actuation-timing for a passive ankle exoskeleton by using musculoskeletal modeling.

Methods

Kinematics and ground reaction forces were recorded while a healthy-young male walked on overground force-plates, and these data were exported to a musculoskeletal modeling software (OpenSim) for simulation. A passive ankle exoskeleton model was designed and integrated with a default …

Reducing Loading On The Contralateral Limb Using Human-In-The-Loop Optimization, Siena Senatore

UNO Student Research and Creative Activity Fair

In most everyday activities, we head towards a specific goal by updating our choices for a more direct path. However, there are specific clinical tasks where taking the direct path is more challenging. Clinical investigations of optimizing a prosthesis involve the assessment of multiple parameter settings through trial and error rather than goal-directed optimization. We investigate if a human-in-the-loop optimization algorithm can guide manual alterations to a prosthesis-simulating device to reduce the ground reaction force on the contralateral limb. In most participants, the optimal condition reduced the loading rate on the contralateral limb compared to the initial condition tested. These …

Mechanical Horse Project, Hernan Ramirez Resendiz, Ben Apt

Mechanical Engineering

This document outlines our senior design project for the Cal Poly Mechanical Engineering Department on behalf of Jack’s Helping Hand. As a team of two Mechanical Engineering students, we developed a structure that can support a rider and can move in three degrees of freedom to model the gait patterns of a horse. This senior project will be continued by another group that will focus on electronics and implement the motors that will induce motion on the structure that our team has built. We collected baseline data by attaching an iPhone to a horse and used that motion to compare …

Astm Test Fixture For Spinal Screws, Sarah K. Pickering, Matthew W. Rowen, Kaajal N. Khanna, Thomas A. Sunding

Biomedical Engineering

This document is an overview report of the Cal Poly Senior Project ASTM Test Fixture for SeaSpine orthopedic bone screws. The main application of orthopedic screws is to fasten implants directly to the bone structure, enhancing structural integrity. Testing for breaking angle, insertion torque, removal torque, axial pullout strength, and self-tapping force as specified in the ASTM F543 Annexes provides the FDA with vital screw mechanics and ensures manufacturing uniformity. The test system is comprised of custom and off the shelf components allowing for interchangeability, in case of part failure, and a low overall cost. It is mechanically capable of …

Algorithms For Rapid Trip Detection In Human Walking Using Inertial Sensors, Chadi Ellouzi

Theses and Dissertations

Trips and falls are one of the most common causes for injuries among elderly. The existing trip-and-falls studies primarily focus on the proactive fall prevention approaches, while active prevention strategies remain largely unexplored. This thesis aims to provide first steps towards active trip-and-fall prevention by developing various algorithms capable of detecting trip in human walking faster than the human voluntary reactions (~200 ms). The measurements of human kinematics are used as the inputs in the algorithms. The proposed algorithms include three threshold-based detection methods, an optimized elastic time-series alignment tool called dynamic time warping (DTW) that overcomes problems of time …

Optimization Of An Automated Algorithm For Analysis Of Spontaneous Rhythmic Bladder Contractions During Urodynamics Testing, Isabelle Pummill, Rui Li, Zachary Cullingsworth, Adam Klausner, John Speich

Summer REU Program

No abstract provided.

Improving Quantification Of Mitral Regurgitation Through Computational Fluid Dynamics And Ex Vivo Testing, Alexandra Flowers

Electronic Theses and Dissertations

Mitral regurgitation (MR) is a prominent cardiac disease affecting more than two million people in the United States alone. In order for patients to receive proper therapy, regurgitant volume must first be quantified. As there are an array of methods to do so, the proximal isovelocity surface area (PISA) method continues to be the most accurate and clinically used method. However, there are some difficulties obtaining the necessary measurements need for this when performing transthoracic echocardiography. This study aims to evaluate and present techniques that may be used to more accurately quantify regurgitation through ex vivo testing and computational fluid …

Structural And Hemodynamic Analysis Of Transcatheter Aortic Valves, Dong Qiu

Electronic Theses and Dissertations

The transcatheter aortic valve replacement (TAVR) procedure has become a well-established procedure for high, intermediate-risk, and low-risk patients. However, there is limited clinical data on the TAV's long-term durability, unlike SAV devices. Computational simulations can be an alternative way to evaluate the TAV devices. This dissertation aims to conduct structural and hemodynamic analyses on the TAV devices under different conditions using computational simulation approaches.

Initially, the impact of the bicuspid aortic valve on the TAV devices was evaluated. The result indicated that the CoreValve-like supra-annular self-expandable device was likely to have increased stress and strain on the leaflet when it …

Non-Invasive Detection Of Elevated Intracranial Pressure Using Spontaneous Tympanic Membrane Pulsation, Rajkumar Dhar

Electronic Theses and Dissertations, 2020-2023

Monitoring intracranial pressure (ICP) is a standard diagnostic tool for various neurological conditions such as head injury, ruptured aneurysms, intracerebral and intracranial hemorrhage, and hydrocephalus. Currently, ICP monitoring relies on invasive pressure measurements. These include intraventricular catheter, subdural screw, epidural sensor, and lumbar puncture. Invasive methods pose the risk of infection and hemorrhage, are expensive, and require special clinical skills. A noninvasive method that is reliable, simple to use, low-cost, and provides easily interpretable results can help avoid the complications associated with the invasive methods. This study proposes a novel method for noninvasive ICP monitoring using tympanic membrane pulsation (TMp). …

Skeletal Modeling Parameters And Clinical Factors Related To Injury Risk In Baseball Pitchers, Aaron Trunt

Dissertations and Theses

ABSTRACT Baseball pitching is a well-studied area of biomechanics partially due to high injury rates in the upper extremity. While current known injury risk factors for pitchers include limited shoulder range of motion (ROM), increased ball velocity, and limited shoulder strength, there has been a lack of scientific evidence linking increased joint kinetics to injury risk. The aims of this research were to (1) explore relationships between known risk factors for injury and joint kinetics, (2) establish more specific biomechanical models of pitchers to calculate joint kinetics with greater precision, and (3) deploy these models prospectively to determine how model …

An Introduction To The Comparison Of Seismocardiography And Phonocardiography, Anna C. Voyatzoglou

Honors Undergraduate Theses

The intent of this thesis is to lay groundwork for examining the relationship between seismocardiography (SCG) and phonocardiography (PCG). Both are methods of measuring and describing heart mechanical function. SCG is described as chest vibrations while the heart beats, and PCG is described as acoustic chest surface signal believed to represent the heart valves opening or closing. SCG and PCG have both been used separately in clinical and research settings, but there is currently no clear comparison between the two. Therefore, there has been no way at the present to understand how one signal might inform the other. This study …

Antagonistic Co-Contraction Can Minimize Muscular Effort In Systems With Uncertainty, Anne D. Koelewijn, Antonie J. Van Den Bogert

Mechanical Engineering Faculty Publications

Muscular co-contraction of antagonistic muscle pairs is often observed in human movement, but it is considered inefficient and it can currently not be predicted in
simulations where muscular effort or metabolic energy are minimized. Here, we investigated the relationship between minimizing effort and muscular co-contraction
in systems with random uncertainty to see if muscular co-contraction can minimize effort in such system. We also investigated the effect of time delay in the muscle, by varying the time delay in the neural control as well as the activation time constant.We solved optimal control problems for a one-degree-of-freedom pendulum actuated by two identical …

Modeling Human Control Behavior In Command-Following Tasks, Sajad Koushkbaghi

Theses and Dissertations--Mechanical and Aerospace Engineering

Humans interact with a variety of complex dynamic systems on a daily basis. However, they are often the lesser understood component of human-in-the-loop (HITL) systems. In this dissertation, we present the results of two HITL experiments to investigate the control strategies that humans use when performing command-following tasks. The first experiment is designed to investigate the control strategies that humans use to interact with nonlinear dynamic systems. Two groups of human subjects interact with a dynamic system and perform a command-following task. One group interacts with a linear time-invariant (LTI) dynamic system and the other group interacts with a Wiener …