Mechanical Engineering Commons^™

An Investigation Of Pelvic Kinematics And Implications For Total Hip Arthroplasty, Kathryn Holland Colone

Electronic Theses and Dissertations

Total hip arthroplasty (THA) is one of the most commonly performed orthopaedic procedures, with approximately 500,000 surgeries performed annually in the United States alone. Although THA is widely regarded as highly successful, postoperative complications persist, highlighting the multifactorial nature of THA outcomes. Previous studies have demonstrated the importance of implant positioning and soft tissue mechanics, yet challenges remain in optimizing surgical decisions on a patient-specific basis. Recent advances in surgical planning tools have shifted the focus of preoperative planning toward optimizing patient-specific outcomes, highlighting the need to better understand how patient anatomy, surgical technique, and joint mechanics interact to influence …

Effects Of Ankle Actuation On Stability And Gait Dynamics In Oscillatory Bipedal Walking, Guillermo E. Selva Barrantes

Electronic Theses and Dissertations

Bipedal locomotion remains one of the most challenging problems in robotics and biomechanical modeling due to its inherent instability, underactuation, and the complexity of human gait dynamics. This study presents the design and control of a planar bipedal walking model developed to analyze the role of ankle control in achieving stable and human-like walking patterns. Two configurations were investigated: a five-link point-foot model and a seven-link model that incorporates anatomically inspired feet with heel and toe contact points. Both models were formulated using Lagrangian dynamics and integrated with a compliant contact and friction model to reproduce realistic ground interaction forces. …

Computational Modeling Of Biophysical Transport: Respiratory Drug Delivery And Tissue-Level Physics, Md Tariqul Hossain

Electronic Theses and Dissertations

The nasopharynx, the upper part of the pharynx located at the back of the nose serves as a critical hotspot for initial respiratory infections via inhaled transmission, largely due to the presence of specific surface receptors that pathogens can exploit for cell invasion, combined with a relatively sparse local mucociliary substrate. To enhance the therapeutic efficacy against certain pathogens, such as the SARS and Influenza viruses, it is therefore essential to improve the targeted delivery of drugs to the nasopharynx. This study explores the use of intranasal sprays as a method for drug administration and models the transport of sprayed …

Numerical Investigation Of Injector Location And Equivalence Ratio In A Flame‐Holder Cavity Scramjet, Matthew Sorenson

Electronic Theses and Dissertations

This thesis presents a CFD-based parametric study of injector location and fuel rate in an ethylene-fueled flame-holder cavity scramjet using STAR-CCM+. Simulations are performed for three injector locations (x/D = 18, 36, and 54) and nine equivalence ratios spanning from ϕ = 0.2 to 1.0 in 0.1 increments. The study aims to determine how injector placement and fueling level alter scramjet performance across a broad operating sweep. The results show a clear regime change between ϕ = 0.2 and ϕ ≥ 0.3. At ϕ = 0.2, combustor behavior is weakly sensitive to injector location compared to the higher-fueling cases. For …

A Study Of Lost Pla Investment Casting For A356 Aluminum In Resource Constrained Manufacturing Environments, Maverick Beckmann

Electronic Theses and Dissertations

Lost PLA investment casting offers a low tooling route for producing complex aluminum parts, but repeatability depends on material use, burnout behavior, geometric process limits, and dimensional response. This thesis evaluated Lost PLA casting as a resource efficient manufacturing method for complex A356 aluminum components in resource constrained settings through four linked objectives: metal reusability, burnout and PLA selection, process limitations, and feature based dimensional shrinkage. A metal mass balance was performed on six casting trials using salvaged A356. Ash residual behavior was studied through a single tray screening test of eight commercial filaments and three invested mold burnout trials …

Computational Fluid Dynamics Simulation Of In-Situ Plasma- Assisted Cold Spray, Lucas Degen

Electronic Theses and Dissertations

Cold spray is a solid-state form of additive manufacturing with high versatility and widespread applicability, especially in relation to metal coatings. Many applications exist within the fields of aerospace, defense and energy systems to obtain sustainable, temperature and corrosion resistant, robust coatings. High-strength alloys and refractory metals generally encounter challenges with regards to cold spray coating adhesion and overall deposition efficiency. Heat induced methods of post-processing or in-situ treatment have been explored to encourage particle softening in the cold spray plume, as well as coating recrystallization to enhance material properties. These approaches have primarily been limited to an experimental approach, …

Thermal Heterogeneity And Lithium Plating During Fast Charging Of Lithium-Ion Battery., Ayodeji Avis Adeniran

Electronic Theses and Dissertations

Presently, widespread adoption of electric vehicles (EVs) is hindered by challenges associated with XFC, including heat generation, lithium plating, and accelerated battery degradation. This dissertation addresses these barriers through two coordinated themes—lithium plating and thermal management—spanning four manuscripts that integrate operando diagnostics, physics-based simulation, and module-level design optimization. The first theme seeks a fundamental investigation into the dynamic interplay between temperature heterogeneity and lithium plating during fast charging, a phenomenon that poses significant limitations on the performance of graphite-based anodes. Firstly, a custom operando cell with a sapphire window was designed to enable synchronized MWIR thermography and optical imaging of …

Scalable Carbon-Based Electrodes For Hole-Transport Layer-Free Perovskite Solar Cells., Sharmin Akter

Electronic Theses and Dissertations

Perovskite solar cells (PSCs) have rapidly reached certified single-junction efficiencies near 26%, but deployment is still limited by operational instability, scale-up challenges, and the cost and complexity of typical device stacks. This dissertation explores a simpler, scalable approach: HTL-free PSCs using low-cost, chemically robust carbon (e.g., carbon black) counter electrodes compatible with low-temperature, solution processing. This work demonstrates how carbon-ink formulation, scalable deposition (blade vs. slot-die), and work-function-tuning additives control film quality, interfacial energetics, and device performance. Carbon inks were developed for both coating methods by systematically varying carbon-to-binder ratio, polymer chemistry, and solvent system. Among the binders screened, ethyl …

Detecting Non-Axisymmetric Instabilities In Fluid-Based Manufacturing Via Multi-View Tensor Analysis., Bidusi Khadka

Electronic Theses and Dissertations

Fluid-based manufacturing processes, such as inkjet printing and electrospinning, fabricate micro- and nano-scale structures with high precision, but are prone to complex fluid dynamics exhibiting axisymmetric and non-axisymmetric instabilities. Conventional monitoring often relies on single-camera inputs and symmetry assumptions, limiting the detection of three-dimensional anomalies like jet deflection. This study presents a novel multi-view streaming video-based anomaly detection framework to address this gap. The framework employs a modified Tensor Sequential Sampling (TSS) algorithm with edge-based sampling to capture geometric spatiotemporal features of each camera view using the videos obtained from an orthogonally positioned dual-camera setup. These features are fused with …

Reproducibility In Modeling Of Knee Joint Mechanics, Maryam Nazem

Electronic Theses and Dissertations

Computational modeling of knee joint biomechanics can provide valuable insights into joint function, injury mechanisms, and patient outcomes, and can support surgical planning and informed clinical decision-making. However, achieving consistent and repeatable results, or reproducibility, is a significant challenge that affects the credibility of these models. This thesis addresses reproducibility through two studies related to the KneeHub Project, which is a multi-institutional collaboration designed to investigate reproducibility in finite-element modeling of the knee.

The first study involved model benchmarking, where predicted results of the calibrated models were compared with the experimental data to evaluate model reproducibility. While all models replicated …

Influence Of Obesity On Knee Joint Mechanics: A Subject-Specific Musculoskeletal Modeling Approach, Ryan C. Knowles

Electronic Theses and Dissertations

Obesity has been consistently linked to knee osteoarthritis (KOA), a debilitating joint disease. While prior work has shown that obese individuals often walk with altered biomechanics compared to normal-weight (NW) individuals, which may accelerate KOA progression, less is known about how these mechanics affect load distribution between the medial and lateral tibiofemoral (TF) compartments, particularly during higher-demand activities. This study developed subject-specific musculoskeletal models of five obese and five NW individuals, incorporating CT-based bone measurements and individualized joint contact points. Simulations were driven by six degree-of-freedom (6DOF) kinematics obtained from high-speed stereo radiography (HSSR) to predict TF loading and associated …

Material Extrusion 3d Printing Of Metal Alloy: Material, Methods And Application., Sihan Zhang

Electronic Theses and Dissertations

Material extrusion (MEX) additive manufacturing presents a promising pathway for producing metal components with complex geometries while avoiding the safety hazards associated with loose powder handling in conventional metal additive manufacturing processes. This dissertation investigates the development and optimization of MEX processes for aluminum alloys, addressing critical challenges in feedstock formulation, printing parameter optimization, and post-processing strategies. Three distinct approaches were explored to advance the capabilities of aluminum MEX: filament-based processing of 6061 aluminum, paste-based extrusion of 6061 aluminum, and development of a novel aluminum-magnesium-tin alloy system for space manufacturing applications. The filament-based approach successfully demonstrated the production of 6061 …

Development Of An Embedded Iot Board For Real-Time Floor Estimation Of Autonomous Robots, Carter J. Sorensen

Electronic Theses and Dissertations

As service robots become more prevalent in multi-story environments such as hospitals, hotels, and laboratories, accurate floor-level detection is critical to ensuring operational reliability. Consider a robot tasked with delivering medical samples in a multi-story laboratory. Without accurate feedback, a robot exiting on the wrong floor could introduce delays, disrupt workflows, or compromise sample integrity. Internet of Things (IoT) technologies offer a way to address these risks by providing real-time error detection and corrective capability. However, current IoT-based floor estimation systems often require invasive modifications to building infrastructure—particularly elevator control panels. These approaches introduce challenges related to cost, liability, backward …

Thermal Characterization Of Lithium-Ion Batteries Under Fast Charging Conditions Using Infrared Imaging., Gowthaman Punithakumar

Electronic Theses and Dissertations

Lithium-ion batteries are widely used across various industries due to their long lifespan, high energy density, low self-discharge rate, and absence of memory effect. However, fast charging of Li-ion batteries can cause problems like lithium plating, mechanical damage, and overheating. Temperature plays a key role in battery performance. Measuring temperature accurately is important to improve battery life, efficiency, and safety. However, accurately measuring a battery's internal temperature remains challenging, and the appropriate measurement method depends on factors like range, accuracy, resolution, and cost. Choosing the right temperature measurement method depends on range, accuracy, resolution, and cost. In this study, we …

Bayesian Model Updating Of Structural Parameters Using Temperature Variation Data., Ujjwal Adhikari

Electronic Theses and Dissertations

Physical digital twins have now emerged as a technology in structural health monitoring and other domains of structural modeling. A Finite Element Model can be a tool for digital twin technology in conjunction with measured physical data. Developing an accurate digital model requires the integration of various parameters to replicate the real structure; however, temperature is dynamically changing, resulting in difficulty in the identification of structural parameters. Typically, temperature is considered noise or filtered out. Limited research has addressed the physics-based model using temperature variation related to structural modal properties. Finite Element Model Updating (FEMU) is a typical inverse problem-solving …

Advancing Tka Biomechanics: From Joint Simulator To Boundary Condition Development, Yashar Ali Behnam

Electronic Theses and Dissertations

This dissertation addresses four specific aims that collectively attempted to advance the experimental and computational analysis of total knee arthroplasty (TKA) components. The first study focused on the development of a novel whole knee joint simulator capable of simultaneous tibiofemoral and patellofemoral knee loading. This simulator employs custom fixturing to facilitate dynamic, unconstrained, muscle-driven PF articulation alongside controlled TF contact mechanics. Validation against experimental measurements showed strong agreement, demonstrating the simulator's potential as a valuable tool for future TKA design and surgical technique investigations.

The second study verified implant-specific physiological boundary conditions which accurately simulate activities of daily living using …

Determinants Of Knee Motion In Health, Disease, And Repair, Sean Edward Higinbotham

Electronic Theses and Dissertations

The human knee joint is a complex and intricate structure, enabling a wide range of motions and facilitating various dynamic activities throughout a person's lifetime. The combination of the knee's complexity and its role as a primary load-bearing joint has made it susceptible to regular wear and tear, leading to pain and the development of Osteoarthritis (OA), to which, the only treatment currently is total knee arthroplasty (TKA). Despite TKA being a mature procedure, 20% of patients receiving a TKA are dissatisfied with their “new” knee. To reduce that 20% dissatisfaction and improve surgical outcomes, orthopedic companies are developing advanced …

Deep Learning Approaches For Predicting Strain Energy In Heterogeneous Materials, Junesh Gautam

Electronic Theses and Dissertations

Finite Element Analysis (FEA) faces computational challenges when analyzing nonlinear and heterogeneous materials. Utilizing the Mechanical MNIST dataset, comprising 60,000 simulated samples of 28x28 pixel domains under large deformation, the study evaluates classical regression methods (Linear Regression, Random Forest, Gradient Boosting) and advanced deep learning architectures (Convolutional Neural Networks (CNN) and Residual Networks (ResNet)). CNN models achieved superior performance, with a Mean Squared Error (MSE) of 4.21 and an R2 value of approximately 0.982, outperforming classical regression models and slightly surpassing ResNet architectures. These deep learning methods automatically learn spatial relationships from pixel-based representations, eliminating the need for manual feature …

Molecular Dynamics Simulation Of Thermal Properties Of Single Walled Carbon Nanotubes, Shiv Nath Jha

Electronic Theses and Dissertations

Molecular dynamics (MD) simulations are a powerful tool for investigating the thermal behavior of carbon nanotubes (CNTs), which are renowned for their exceptional thermal conductivity and potential in nanoscale thermal management applications. This study employs the open-source software LAMMPS, in conjunction with VMD for model generation, to explore the thermal transport properties of (10,10) single-walled carbon nanotubes (SWCNTs) using non-equilibrium molecular dynamics (NEMD). The thermal conductivity of SWCNTs was evaluated across four tube lengths (5 nm, 10 nm, 20 nm, and 40 nm) and at temperatures ranging from 300 K to 600 K under two distinct boundary conditions: free boundary …

Design And Optimization Of The Injection Molding Process Of Glass Fiber Reinforced Polymeric Car Fender Using Computational Simulation, Synthia Ferdouse

Electronic Theses and Dissertations

The increasing demand for lightweight and energy-efficient materials in the automotive industry has accelerated the adoption of fiber-reinforced polymer composites. This research presents the design and optimization of the injection molding process for glass fiber-reinforced polymer (GFRP) car fenders using computational simulation. The effects of various gate types and locations on key process parameters, including fiber orientation, volumetric shrinkage, shear rate, and fill time, were investigated using Finite Element Analysis (FEA), Autodesk Moldflow Insight 2024, and MATLAB-based Multi-Criteria Decision-Making (MCMD) techniques. Simulations were conducted across multiple configurations involving three, four, and five gates, with several variations in location. Among all, …

Development Of A Collagen-Based Bioink For 3d Printing Biomimetic Tendon-To-Bone Tissue Grafts For Rotator Cuff Repair, Samiul Nibir

Electronic Theses and Dissertations

This study presents the development of a collagen-based bioink for 3D printing tendon-to-bone tissue grafts, specifically designed for rotator cuff repair applications. Three different bioink formulations were developed: (i) 5.1% (w/v) collagen I, (ii) 5% (w/v) collagen I and collagen II, and (iii) 4.5% (w/v) collagen I combined with β-TCP. The bioink containing collagen I and collagen II was prepared by mixing the two components in a 1:1 ratio, while the collagen I plus β-TCP formulation was made by incorporating 20 wt % β-TCP into the collagen I solution. These formulations were developed to replicate the natural tendon-to-bone complex interface …

Modeling Fluid Flow In Complex Biological Systems: Implications For Dense Tumor Microenvironments, Metastasis, And Bone Cancer, Mohammad Mehedi Hasan Akash

Electronic Theses and Dissertations

The transport of biofluids in physiological systems plays a critical role in understanding and optimizing therapeutic interventions for diseases such as cancer and respiratory infections. This dissertation focuses on developing and validating a comprehensive computational framework for studying multiphase transport in complex biological environments. The research emphasizes the use of Computational Fluid Dynamics (CFD) to simulate and analyze plasma perfusion in solid tumors, particle deposition in respiratory airways, and fluid transport in cancer metastasis and bone cancer systems. By addressing the challenges of modeling biological transport phenomena, this work provides valuable insights into therapeutic planning and experimental validation. The study …

Optimizing Hypersonic Scramjets: A Numerical Study Of Fuel Type And Cavity Flameholder Design Impacts On Supersonic Combustion, Delaney Baumberger

Electronic Theses and Dissertations

This thesis presents recommendations for optimizing hypersonic scramjets via a numerical study focusing on fuel type and cavity flameholder design and the impacts they have on supersonic combustion. The research is divided into two main investigations aimed at improving scramjet engine efficiency using two distinct geometrical configurations, a square cavity engine and an axisymmetric cavity engine. Each configuration is examined under Mach 2 inflow conditions to assess the role of geometric variation and fuel selection on combustion stability, flameholding, and overall performance. The first study focuses on a comparative assessment of hydrogen and ethylene as scramjet fuels to evaluate their …

Quantitative Assessment And Validation Of Thermal Profiles In The Protodune-Ii Horizontal Drift Detector Using Computational Fluid Dynamics, Hunter Wallster

Electronic Theses and Dissertations

The Deep Underground Neutrino Experiment (DUNE) aims to advance understanding of neutrino properties using large liquid Argon time projection chambers (LArTPCs). The ProtoDUNE-II Horizontal Drift (HD) detector, constructed at CERN in Switzerland, serves as 1:20 scale prototype to validate design and operational parameters for DUNE’s Far Detectors. Accurate prediction of cryostat thermal behavior is critical to predicting liquid Argon purity distributions and detector performance, motivating the development of a validated computational fluid dynamics (CFD) model. This research extends previous work at South Dakota State University by constructing a higher-fidelity CFD simulation of ProtoDUNE-II HD using Siemens Simcenter StarCCM+® 19.04.007. Geometry …

Mid-Scale Rover Gravity Offloader (Mrgo): Design, Implementation, And Experimental Validation, Alexander Schaar

Electronic Theses and Dissertations

This thesis presents the design, implementation, and validation of the Mid Scale Rover Gravity Offloader (MRGO), a terrestrial testbed developed to simulate partial-gravity conditions for planetary rover testing within a three-dimensional environment. The MRGO enables consistent, user-defined offloading force as a rover drives freely within a 20 by 18 ft test area, while a stepper motor rail gantry autonomously tracks the rover’s motion and maintains overhead alignment. Mounted to the moving gantry is a vertical carriage column that houses the offloading mechanism, which accommodates up to 5 ft of vertical displacement without loss of force accuracy. This configuration allows realistic …

Simulating Positive Ion Distribution In The Protodune Single Phase Detector, Vishnu Pfeiffer

Electronic Theses and Dissertations

This work covers the validation and implementation of a model to solve for argon ion (Ar+) distribution in the ProtoDUNE-SP liquid argon time projection chamber (LArTPC). ProtoDUNE-SP undergoes a constant flux of cosmic ray muons due to surface operation. The performance of the ProtoDUNE-SP provided valuable insights into single-phase technology, membrane cryostat technology, and calibration of cryogenic instrumentation. Still, challenges in achieving precise measurements persist due to the space charge effect—the distortion of the electric field within the detector due to the accumulation of positive argon ions generated from constant cosmic muon flux. The overarching goal of this thesis is …

Lunar Payload Logistics: Advancing Autonomous Control For Lunar Surface Transporter Vehicles, Liam Murray

Electronic Theses and Dissertations

No abstract provided.

Molecular Dynamics Simulations Of Key Parameters On Thermal Properties Of Carbon Nanotube Modified Epoxy Composites, Lida Najmi

Electronic Theses and Dissertations

The application of carbon nanotube (CNT)-reinforced epoxy matrix composites (CRECs) has attracted extensive attention in various industrial sectors due to the significant improvement of material properties imparted by CNTs. The thermal behavior of these nanocomposites is governed by complex heat transfer mechanisms operating at different scales, resulting in a complex relationship between the effective thermal response and the microstructural characteristics of the composite. In this study, molecular dynamics (MD) simulations were used to investigate the thermal conductivity of CRECs, focusing on the effects of key parameters such as the length and volume fraction of CNTs, the degree of cross-linking within …

Sensitive Grip Mounting Surfaces For Physical Human-Robot Interaction., Branden Shay

Electronic Theses and Dissertations

As the development of robotics becomes ever increasingly present in our society, the need for studying how humans and robots interact with each other becomes more of a necessity to be properly integrated in the changing world around us. In this thesis, we undertake the study and development of how to create a tactile human-robot operator interface to guide a robot perform a physical task. The implementation of tactile interfaces such as SkinCell sensor arrays emulating skin, and of a robotic handlebar fitted with tactile sensors are critical examples of the challenges that come with mounting and packaging such sensors …

Modeling And Understanding Of Additive Manufacturing Periodic Cellular Structures With Heterogeneity: Property, Quality And Design Strategy., Naresh Koju

Electronic Theses and Dissertations

Lightweight cellular structures with their higher per mass performance capability, multifunctional designability and property tolerability are gaining much wider adaptation in many engineering applications ranging from aerospace, defense, biomedical, automotive to sports. However, to achieve the desired performance levels careful design must be carried out. The experimental-based empirical design often involves high manufacturing cost, and there are also certain information/knowledges about the cellular deigns that could not be easily obtained experimentally, such as the deformation local fracture initiation. Similarly, numerical modeling-based design approach commonly suffers from high computation cost and the lack of inverse designability. In addition, numerical models often …