Biomechanical Engineering Commons^™

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.

In-Flow Dynamics Of An Area-Difference-Energy Spring-Particle Red Blood Cell Model On Non-Uniform Grids, Brendan Walsh, Fergal Boyle

Articles

In this paper the area-difference-energy spring-particle (ADE-SP) red blood cell (RBC) structural model developed by Chen and Boyle is coupled with a lattice Boltzmann flux solver to simulate RBC dynamics. The novel ADE-SP model accounts for bending resistance due to the membrane area difference of RBCs while the lattice Boltzmann flux solver offers reduced computational runtimes through GPU parallelisation and enabling the employment of non-uniform meshes. This coupled model is used to simulate RBC dynamics and predictions are compared with existing experimental measurements. The simulations successfully predict tumbling, tank-treading, swinging and intermittent behaviour of an RBC in shear flow, and …

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 …

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 …

Controlled Voltage Of Hot Snare Polypectomy Device In Electrosurgical Device, Saidi Olayinka Olalere

College of Graduate Studies: Theses & Dissertations

The study is used to understand the working procedure of the Olympus PSD-30 Electrosurgical Unit which a high-frequency alternating current is to measure the voltage and power output from the unit when used for a surgical operation to determine the extent of tissue damage. The output power and voltage were as examined with the stopwatch, then with an Arduino time based for 1, 2, and 3 seconds to understand the different modes of the cut and coagulation feedback with an RCC circuit used to mimic the human body. This shows a pattern in which the feedback power increases, and voltage …

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 …

Contact Simulation For Evaluating Patient Specific Surgical Guide Stability, Vincent Nierste

Electronic Theses and Dissertations

This study proposes a novel computational method to quantify guide stability for Patient Specific Instrumentation (PSI) guides. A finite element contact model was used to analyze the final position of PSI guides on a femur across a range of loading parameters representing forces applied by a surgeon during operative use. Separate segmentation methods were used for the guide and bone geometry to represent differences between segmentation and actual patient geometry. The region of loading parameters over which the guide exhibited a consistent final position was measured and reported as Guide Stability Score. The model was verified using cadaver specimens for …

Numerical Design Of Steerable Guidewires, Onkar Prakash Salunkhe

Dissertations, Master's Theses and Master's Reports

Biomedical devices are an integral part of the medical industry nowadays. With the increase in cases of heart disease, catheterization procedures are becoming more frequent. Small-scale actuators are needed for the guidance of small-scale catheters and guidewires to remote targets in the human body. Numerical modelling is needed to guide the experiments in developing such steerable devices and to optimize their design. Here, we designed small-scale steerable guidewires by first developing bending actuators and then assembling them with guidewires. The actuators use materials with strain response to electric potential in a very low voltage range that is not harmful to …

Design Of Human Inspired Feet For Mithra, A High-Performance Humanoid Robot, Spencer Lyle Brewster

Electronic Theses and Dissertations

This thesis explores the foot design for the new humanoid robot Mithra, with the goal to improve impact mitigation, natural gait throughout the gait cycle and balance. Using human gait parameters, a stiff aluminum foot was designed to emulate human center of pressure rollover trajectories. In addition, a 2D dynamic Finite Element Analysis (FEA) of the gait cycle was created in Abaqus to rapidly prototype foot designs. Data from the FE model provided impact forces, parameters for distal foot power evaluation and maximum lean angles. From this model a flexible nylon foot was optimized for the given design objectives. The …

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 …

Morphologic Clustering Of Earcanals Using Deep Learning Algorithm To Design Artificial Ears Dedicated To Earplugs Attenuation Measurement, Bastien Poissenot-Arrigoni, Chun Hong Law, Djamal Berbiche, Franck Sgard, Olivier Doutres

Études primaires

Designing earplugs adapted for the widest number of earcanals requires acoustical test fixtures (ATFs) geometrically representative of the population. Most existing ATFs are equipped with unique sized straight cylindrical earcanals, considered representative of average human morphology, and are therefore unable to assess how earplugs can fit different earcanal morphologies. In this study, a methodology to cluster earcanals as a function of their morphologies with the objective of designing artificial ears dedicated to sound attenuation measurement is developed and applied to a sample of Canadian workers’ earcanals. The earcanal morphologic indicators that correlate with the attenuations of six models of commercial …

Modeling Of Patient-Specific Periaortic Mechanics And Pulmonary Artery Hemodynamics Based On Phase-Contrast Magnetic Resonance Imaging Sequences., Johane H. Bracamonte

Theses and Dissertations

Inverse modeling in cardiovascular medicine is a collection of methodologies that can provide non-invasive patient-specific estimations of clinical risk factors using medical imaging as inputs. Its incorporation into clinical practice has the potential to improve diagnosis and treatment planning with low associated risks and costs.

Herein, three different phase contrast magnetic resonance imaging (MRI) modalities were implemented as input data, displacement encoding with stimulated echoes (DENSE MRI) applied, and time-resolved velocity encoding phase-contrast MRI, in 1D and 3D, applied to pulmonary artery (PA) hemodynamics.

A model to account for the effect of periaortic interactions due to static and dynamic structures …

Prolonged Exposure To Microgravity Increases Susceptibility To Traumatic Brain Injury, Ryan Baskerville

UNF Graduate Theses and Dissertations

With the prospect of semi-permanent and permanent habitable fixtures on the moon and Mars, the complications associated with long-term exposure to microgravity should be investigated exhaustively. Spaceflight Associated Neuro-Ocular Syndrome (SANS), a group of neurological and ocular effects resulting from prolonged exposure to microgravity, is characterized by significant fluid shifts into the cranium, namely cerebrospinal fluid and blood, and an upward shift of the brain relative to the skull. This syndrome, along with its immediate effects on visual acuity, cognitive ability, and motor function are recognized by NASA, but its effects on susceptibility to traumatic brain injury have yet to …

A Survey Of Stainless Steel In Medical And Surgical Application, Noah Slack, Clint Balch

ME 4133/6133 Mechanical Metallurgy

Stainless steels can be separated into four families based on the microstructure of the material: Austenitic, Ferritic, Martensitic, and Duplex. Each family provides a specific set of advantages and disadvantages, and material selection should be based on the specific application the material will be used for. For this study, the processing, microstructure, and performance of the four families of stainless steels will be compared in the context of medical device applications. The most important factors in medical device materials are biocompatibility, surface properties, mechanical properties and life span/corrosion resistance. This study will focus on medical devices that will be permanently …

Force-Feedback Design For Robotics: Bio-Based Design And Simulation, Husnain Khan, Zhou Zhang

Publications and Research

The great challenge for the Virtual Assembly Platform is how to make the users have the in-person feeling with the augmented tools. Hands are the most important organs that are used to provide touch feeling. In a real assembly scenario, the force from the components and tools will be feedback to the brain via the hands. Unfortunately, the virtual assembly failed to mimic the in-person scenarios since it will not provide such kind of feedback. As a result, the users’ real identities are lost. Then, the users’ slower-progressing wrong habits will prevent them from success in the future. Therefore, it …

Respiratory Compensated Robot For Liver Cancer Treatment: Design, Fabrication, And Benchtop Characterization, Mishek Jair Musa

Graduate Theses and Dissertations

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death in the world. Radiofrequency ablation (RFA) is an effective method for treating tumors less than 5 cm. However, manually placing the RFA needle at the site of the tumor is challenging due to the complicated respiratory induced motion of the liver. This paper presents the design, fabrication, and benchtop characterization of a patient mounted, respiratory compensated robotic needle insertion platform to perform percutaneous needle interventions. The robotic platform consists of a 4-DoF dual-stage cartesian platform used to control the pose of a 1-DoF needle insertion module. The active …

Medial And Lateral Tibiofemoral Contact Forces For Individuals With High Body Mass Index In Gait And Cycling Training, Reymil Fernandez

Master's Theses

The prevalence of knee osteoarthritis, a degenerative joint disease characterized by the degradation of articular cartilage, is correlated with the rise in obesity. The rising rates of obesity in children and adults highlight the need for identifying a sustainable physical activity that promotes fitness while mitigating initiation and progression of osteoarthritis. The objective of this study was to determine an effective rehabilitation and lifelong fitness sustainment exercise regimen that minimize risk of osteoarthritis in individuals with high body mass index (BMI). The aim was to examine knee medial and lateral contact forces in gait and cycling training. Gait at self-selected …

Triangular Cosserat Point Element Method For Reducing Soft Tissue Artifact: Validation And Application To Gait, Jake Edward Deschamps, Stephen Klisch

Master's Theses

Human motion capture technology is a powerful tool for advancing the understanding of human motion biomechanics (Andriacchi and Alexander, 2000). This is most readily accomplished by applying retroreflective markers to a participant’s skin and tracking the position of the markers during motion. Skin and adipose tissue move independently of the underlying bone during motion creating error known as soft tissue artifact (STA), the primary source of error in human motion capture (Leardini et al., 2005).

(Solav et al., 2014) proposed and (Solav et al., 2015) expanded the triangular Cosserat point element (TCPE) method to reduce the effect of STA on …

Using Dynamic In Vivo Kinematics For Subject-Specific Calibration Of Knee Ligament Parameters, Stephen Nelson

Boise State University Theses and Dissertations

In vivo clinical studies are the optimal way to investigate the biomechanical outcomes of new prosthetic devices. This particular style of testing can be difficult and, in certain cases, unethical to perform. The testing of unproven devices, surgical techniques, and materials put patients at risk from unanticipated outcomes in how these devices respond to the in vivo environment and patient-specific loading conditions. Biomechanical computational models were developed to provide validation to new devices prior to clinical testing. Computational models for use in optimizing knee prosthetics frequently include ligament representations, but these representations have inherent uncertainty due to wide intersubject variation …