Mechanical Engineering Commons^™

Numerical And Machine Learning Based Recreation Of Damage Morphologies Of Barely Visible Impact Damage, Oscar A. Valdez

Mechanical and Aerospace Engineering Dissertations

Composite laminates are highly sought after in the aerospace industry as they provide strength without dramatically increasing the weight of manufactured structures. However, composite laminates are susceptible to barely visible impact damage caused by routine activities. This type of damage can easily go unnoticed while significantly reducing the load-carrying capability of the laminate. Current non-destructive evaluation techniques, such as ultrasonic scanning, can reveal the damage footprint but provide no insight into delamination through-the-thickness due to the shadowing effect. Micro-computed tomography offers ply-by-ply damage resolution but is unsuitable for field inspections and is constrained by specimen size. This study aims to …

System-Level Assessment Of Non-Ideal Phase Change Material Behavior In Low Earth Orbit Spacecraft Thermal Control Models, Nathan S. Bruursema

Dissertations, Master's Theses and Master's Reports

Phase change materials (PCMs) are of interest in spacecraft thermal control because their latent heat capacity can provide passive thermal buffering during transient or cyclic heat loads. PCM behavior is often treated using idealized assumptions such as repeatable phase transition temperatures, consistent thermal accessibility across cycles, and full latent recovery. However, practical PCM behavior may be affected by non-ideal phenomena such as supercooling, interfacial resistance, and degradation of internal transport accessibility. This thesis examines the system-level relevance of these effects for low Earth orbit (LEO) spacecraft thermal control and identifies the operating conditions under which non-ideal PCM behavior becomes design-relevant. …

Development And Calibration Of A 2-D Diesel Oxidation Catalyst Filter (Docf) Model With Spatially Varying Washcoats Using Spacims And Engine Loading Data, Thomas K. Price

Dissertations, Master's Theses and Master's Reports

Diesel engine exhaust contains regulated species, including carbon monoxide, hydrocarbons, nitrogen oxides, and particulate matter (PM). Meeting increasingly stringent emission standards typically requires multiple aftertreatment components, motivating the development of multifunctional devices that reduce system size, cost, and catalyst usage. Computational models are essential for guiding this design process; however, existing models primarily focus on single-function devices and rarely capture the behavior of multifunctional systems with multiple catalyst washcoats. This work presents a physics-based model of a wall-flow diesel oxidation catalyst filter (DOCF), a multifunctional device that integrates the roles of a diesel oxidation catalyst and a diesel particulate filter …

A Multiobjective Framework For Joint Coverage And Motion Planning In Uav Inspection Tasks, Luis Fernando Escobar Carvajal

Graduate Theses, Dissertations, and Problem Reports (ETD)

Unmanned Aerial Vehicles (UAVs) have become essential for data acquisition in complex 3D environments. However, traditional Coverage Path Planning (CPP) methodologies often rely on a sequential pipeline that isolates viewpoint generation from flight path routing. This decoupling fails to account for the interdependence between viewpoint distribution and minimum flight paths, effectively restricting the search space and preventing the identification of a global optimum. This dissertation proposes a unified multi-objective framework for joint coverage and motion planning. The primary contribution of this work is the transition from isolated, sequential steps to a simultaneous optimization of the number and position of viewpoints …

Hvac Design And Calculations, Sarah Walters, Sarah Beyea

Williams Honors College, Honors Research Projects

This project studies Heating, Ventilation, and Air Conditioning (HVAC) systems for a car dealership located in Seguin, Texas. The building construction and architectural drawings were provided by EPIC Engineering Group. Comprehensive load calculations were done on the building in order to calculate necessary airflows throughout the building. Three possible HVAC design solutions were compared: Rooftop Units (RTUs), rooftop units paired with Variable Air Volume (VAV) Terminals with electric reheat, and Variable Refrigerant Flow (VRF) paired with a Dedicated Outdoor Air Unit (DOAS). Energy modeling was completed to compare the utility costs and energy consumption of each system. A comprehensive weighted …

Akron Soap Box Derby Super Kids Car, Alexis Schultz, Cooper Sites, Sean Stevenson

Williams Honors College, Honors Research Projects

This project aims to redesign the All-American Soap Box Derby Super Kids vehicle to enhance safety, accessibility, and performance while maintaining full compliance with official regulations. The Super Kids program enables children with physical and cognitive disabilities to race alongside a co-pilot, but the current vehicle design presents challenges in stability, entry/exit accessibility, and control—especially following recent regulation changes that increased vehicle speed. The redesigned car will focus on improved ergonomics, lightweight construction, and structural integrity within a $1,000 budget and a 165 lb weight limit.

An iterative engineering design process will guide the project through research, CAD modeling, FEA …

Kruss Modifications, Anderson W. Howard

Williams Honors College, Honors Research Projects

My project focuses on modifying a test device in the AETL to allow for high temperature test to be performed. I am also adding modifications to make it safer to perform tests using the high-pressure system.

Development Of Hydrogen Emissions Quantification Systems To Expand Understanding Of Leaks And Losses Associated With The Burgeoning Hydrogen Transportation Sector, Christopher Loomis

Graduate Theses, Dissertations, and Problem Reports (ETD)

To combat global warming, alternative fuels are being investigated. Hydrogen is at the forefront of this movement, advertised as having zero emissions due to the products of the energy reaction being only water. However, studies over recent decades indicate that hydrogen in the atmosphere acts as a form of greenhouse gas (GHG) by increasing the lifespan of methane in the atmosphere. Models are attempting to estimate the possible effects of a transition to a hydrogen-fueled economy but lack empirical data to provide confidence to these estimated values. There is little data that quantifies hydrogen from anthropogenic sources.

To address this …

Design, Testing And Controls For Air Source Heat Pump System In Cold Climates Using Natural & Conventional Refrigerants, S M Abdur Rob

Dissertations and Theses

Fossil-fuel based heating systems used in the residential buildings in northeastern U.S region are not only inefficient but also largely responsible for the greenhouse gas emissions in U.S. Electrification of the buildings has been proved to be the most efficient way to reduce the greenhouse gas emissions where Heat Pumps can be the best alternative to replace the natural gas based heating system to accelerate the electrification process. Among different types of heat pumps, the Air Source Heat Pump (ASHP) system is widely used due to the easy installation and energy efficiency. Conventional heat pump technologies use various types of …

Multi-Objective Optimization Strategy For Component Sizing In Solar-Hydrogen Microgrids Using An Advanced Hybrid Genetic Algorithm, Dylan Jones

UNF Graduate Theses and Dissertations

This thesis presents the development of a genetic algorithm (GA) optimization framework for the design and component sizing of hybrid solar-hydrogen microgrids. The framework addresses a critical gap in research and existing commercial tools by unifying performance maximization and cost minimization objectives across both grid-tied and islanded configurations. Integrating solar photovoltaics, electrolyzers, hydrogen storage, fuel cells, and batteries, the GA employs adaptive weighting and dynamic boundary constraints to balance technical feasibility with economic efficiency. To ensure real-world viability, the algorithm relies on a novel Daylight Sun Factor (DSF) for localized solar assessment and was rigorously validated against multi-year, high-fidelity irradiance …

Application Of Reactive Power Theory To Wave Energy Converters Under Multi-Frequency Excitation: Analysis And Experimentation, Mckenna R. Collins

Dissertations, Master's Theses and Master's Reports

There is abundant energy surging in the oceans across the globe. However, there have been technological challenges in extracting that energy for use. Wave energy converter (WEC) technology is being developed to find innovative ways to convert wave kinetic energy into electricity, but there are still efficiency obstacles that inhibit large-scale use. Focusing on heave-point absorber control theory, this thesis continues the work to improve the efficiency of WECs. This is done by leveraging a superposition of linear mass-spring-damper models to analyze a WEC under multi-frequency excitation and applying proportional-derivative gains to each linear model. However, to analyze this system, …

Virtual Process Modeling Of Metal Additive Manufacturing Basedon Direct Energy Deposition In-Situ Failure, Jachin J. Ramirez

2025 Fall Honors Capstones Projects - Archive

This study builds a mesoscale finite element simulation to examine how internal stresses form during additive metal manufacturing using directed energy deposition. The goal is to track how heat and stress develop layer by layer and determine where a failure criterion could appear during the print. The model uses temperature-dependent material properties for Inconel 718 and a moving heat source defined with custom G-code.

Thermal results are mapped into a mechanical simulation to watch stress accumulate as new layers are added. Different scan paths were tested to determine whether varying heat exposure could reduce the extent of a region exceeding …

Computational Study Of Cavitation In An Inducer Pump, Jaylen Leonard

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cavitation is ubiquitous in liquid-handling turbomachines. Cavitation bubbles form when the local pressure drops below a fluid’s vapor pressure, and their subsequent collapse causes implosions that generate shockwaves and microjets. These effects lead to fluid instability and structural damage to the blades and casing in turbomachines. This thesis investigates this cavitation phenomenon in turbomachines using Computational Fluid Dynamics (CFD). The cavitation model built in ANSYS Fluent® is first validated in a venturi tube model and then applied to an inducer pump. The geometry of the pump is derived from the Space Shuttle Main Engine (SSME) Low Pressure Oxidizer Pump (LPOP) …

Stability Analysis Of Thermohaline Convection With A Time-Varying Shear Flow Using The Lyapunov Method, Kalin Kochnev

Honors Scholar Theses

This work applies the Lyapunov method to identify instabilities and compute the growth rate of a linear time-varying system. The linear system studied describes cold fresh water on top of hot salty water with a periodically time-varying background shear flow. A time-dependent weighting matrix is employed to construct a Lyapunov function candidate. The resulting linear matrix inequalities are discretized in time using the forward Euler method. As the number of temporal discretization points increases, the growth rate predicted by the Lyapunov method or Floquet theory, used for comparison, will converge to the same value obtained from numerical simulations. Furthermore, the …

Capillary Imbibition Of Shear-Thinning Xanthan Gum Solutions, Aimee Sayster

All Theses

Capillary rise in confined geometries plays a critical role in numerous natural and industrial processes. While classical models such as the Lucas–Washburn equation accurately describe the dynamics of Newtonian fluids, they fail to capture the complex behavior of shear-thinning, non- Newtonian fluids whose viscosity varies with shear rate. This research investigates the capillary rise dynamics of shear-thinning xanthan gum polymer solutions in capillary tubes. The rheological behavior of each fluid is characterized using the Ellis model, which accounts for shear-thinning effects through three key parameters: zero-shear viscosity μ0, characteristic shear stress τ1/2 and viscosity index α. Experimental data was collected …

Locomotion And Balance Control In A Biped Robot With Continuum Legs And A Kangaroo-Inspired Tail, Gavin A. Platt

All Theses

This thesis work presents the design, testing, and validation of a continuum-legged biped robot equipped with a kangaroo inspired tail for enhanced stability and adaptability. Unlike traditional rigid link robots, this one expands on soft-legged robots and utilizes tendon-driven continuum robots to mimic octopus and kangaroo behavior for locomotion. The robot uses a hierarchical hybrid control framework to implement walking, obstacle avoidance, vaulting, and push recovery behaviors. To test the performance of the robot four sets of experiments were conducted to validate these systems and evaluate how they performed. The results demonstrate stable walking with rhythmic tail load transfer, effective …

Multi-Cater Pack Heat Sealer, Ivan Medina-Zepeda, Laurent Hirakata, Donovan Furtado, Cody Ngan

Mechanical Engineering

The Multi-Cater Pack Heat Sealer was developed to support Achievement House, a non-profit organization that employs adults with intellectual and physical disabilities and is facing increasing demand for sealed cater packs. Existing single-pack sealers limited both throughput and accessibility, which led to the creation of a 3D printed attachment for a 40-inch impulse heat sealer. The attachment allows nine packs to be sealed at the same time and includes a tray-style trapdoor that allows for quick unloading. The need for accessibility and usability guided the design throughout the process. Alignment guides improve placement consistency, and the ergonomic layout accommodates both …

Experiential Learning And The Revitalization Of Manufacturing Education At The University Of Dayton, Sean Cahill

Research and Reflection on Learning and Teaching in Higher Education

This perspective paper explores the role of experiential learning in preparing future-ready manufacturing engineers at the University of Dayton, set against the backdrop of Dayton’s legacy as an industrial innovator and the broader national movement to revitalize domestic manufacturing. As automation, cyber-physical systems, and Industry 4.0 technologies reshape the manufacturing landscape, there is a growing need for engineers who possess both technical fluency and systems-thinking capabilities. To meet this need, the manufacturing engineering technology department implemented hands-on, integrated lab-and-lecture modules through support from the Experiential Learning Innovation Fund for Faculty (ELIFF). Grounded in Kolb’s Experiential Learning Theory and constructivist learning …

Design Of Ballistic Armor Using Multi-Composite Sandwich Structures With Nanomaterial Additives, Carmen Alaichamy

College of Engineering Summer Undergraduate Research Program

This study explores the bulletproof capabilities of Kevlar composites fabricated using advanced additive manufacturing techniques. Continuous fiber reinforced 3D printing (CFRP) is employed to produce Kevlar-reinforced polymer matrix composites (PMCs) with optimized structural configurations for ballistic protection. The primary objective is to evaluate the impact resistance of these composites against 9mm projectiles through systematic experimental testing. A series of ballistics tests are conducted using a high-velocity gas-gun system to fire 9mm projectiles at varying speeds angles. The tests will be conducted at the San Luis Obispo Range, with projectiles fired at various angles. The effects of fiber volume fraction, reinforcement …

Leveraging Smartphones For Balance Assessment, Kelly Graham

College of Engineering Summer Undergraduate Research Program

Assessment of human balance provides valuable metrics to track the health, development, and fall risk of individuals. The prominent method for objective balance assessments has used force plates to track the center of pressure (COP) position as a participant attempts to balance during varying tasks. However, the use of force plates is limited by the cost of equipment and expertise required, leading to recent interest in using embedded inertial measurement units (IMUs) in mobile devices instead. Many researchers have explored placing mobile devices close to the subject’s center of mass (COM) to approximate the subject’s COM acceleration and using the …

Comparison Of Anti-Fouling Performance Of Textured Glass Surface Fabricated By Ductile-Mode Peening And Precision Grinding, Hayato Tagaya, Yutaka Kameyama, Shuhei Kodama, Hideaki Sato, Kento Shinagawa, Ayumu Sekiguchi, Seiji Hirai, Hitoshi Ohmori

15th International Conference on Shot Peening

Recently, there has been a growing demand for precision processing glass. In addition to dimensional accuracy, surface texturing to impart functional properties has attracted increasing attention. For example, anti-fouling performance against powder adhesion is required for cover glasses of solar cells. Powder adhesion is governed by van der Waals forces, which depend on the surface texture of the substrate, suggesting that surface structures influence adhesion behavior. Our previous study demonstrated that angled fine particle peening (FPP) could fabricate a nanoscale fine texture on glass surfaces through ductile-mode peening—glass processing without brittle fracture. In this study, the effect of surface texturing …

Roughness Parameters For Evaluating Blasted Or Shot Peened Surfaces, Stefanie Stoeckel, Sophie Groeger

15th International Conference on Shot Peening

A review of the papers presented at the last three International Conferences on Shot Peening revealed that the most used parameters are Ra and Rz. There has been comparatively little exploration of other parameters, particularly the S-parameters. Furthermore, the ISO 4287 standard for profile parameters was replaced by the new ISO 21920-2 standard in 2021. This is accompanied by the introduction of new parameters as well as alterations to existing ones. This paper demonstrates the limitations of Ra and Rz, as well as Sa and Sz, and explores additional areal and profile parameters that are useful for the description of …

The Effects Of Shot Peening Highly Loaded Compression Springs, David J. Breuer

15th International Conference on Shot Peening

The compression spring in this test study is typical of one used in a demanding off-road vehicle suspension. The cyclic loads applied during fatigue tests were severe enough to cause failure in approximately 11,000 cycles without shot peening.

The objectives of this study were the following: (1) Design a compression spring similar to those used in the off-road recreational industry. (2) Design & manufacture a fatigue test stand that could withstand high loads for months of testing. (3) Generate a matrix of shot peening treatments to produce different amounts of residual compressive stress. (4) Measure the shot peening residual compressive …

Computational Fluid Dynamics (Cfd) Modeling For Bio-Inspired Aerodynamic Optimization In Autonomous Drones, Hyginus C.O. Unegbu, Danjuma Saleh Yawas

Makara Journal of Technology

This study explores the aerodynamic benefits of bio-inspired design modifications for autonomous drones using advanced Computational Fluid Dynamics (CFD) simulations. Four bio-inspired configurations—leading-edge serrations, winglets, riblet surfaces, and curved wings—were assessed and compared against a baseline drone model to evaluate their impact on aerodynamic performance. The results indicated that all bio-inspired designs significantly enhanced lift, reduced drag, and improved overall aerodynamic efficiency. The leading-edge serration configuration achieved the highest performance gains, with a 33.6% increase in maximum lift coefficient (CL) and a 29.5% improvement in lift-to-drag ratio (CL/CD), primarily due to delayed flow separation and reduced turbulence. Winglets minimized wingtip …

Implementation Of Reliability Centered Maintenance On Crude Booster Pump, Dzulfikar Ali Hafizh, Maya Agustianingrum Putri St., Ph.D., D. Rizal, Adzra Qanita

Journal of Materials Exploration and Findings

Crude oil booster pump is one of the critical equipment in oil refinery operations. In aging plants that have been operating for more than 25 years, where reliability and maintenance issues on equipment often cause operational disruptions and even unplanned shutdowns. This study aims to develop a structured reliability-centered maintenance (RCM) strategy for crsude oil booster pump systems that is also in line with the principles of asset integrity management system (AIMS). This methodology follows the RCM II approach, starting with system function analysis, failure mode identification, and criticality assessment through Failure Mode, Effect, and Criticality Analysis (FMECA) to determine …

Integration And Testing Of A Quadruped Robot With Ros2, Jeremy S. West

Master's Theses

The Cal Poly Legged Robotics Group has been developing research and teaching platforms for agile legged robotics since 2020. These platforms are expected to provide students with opportunities to develop complete legged-robot systems from low-level control to advanced robotics tasks such as motion planning and decision making. However, the current prototyped quadruped robot lacked the software and sensing capabilities for high-level quadrupedal gaits and advanced robotic research.

To address these challenges, this project developed Switch, a robotic platform that builds upon the previous BRUCE platform with significant hardware and software upgrades. Switch features a modular design that allows individual software …

Synergistic Enhancement Of Tribological Behavior And Colloidal Stability In Cuo Nanolubricants Via Ligand Tuning, Sherif Elsoudy, Sayed Akl Akl Dr, Sayed Akl A. Akl Dr, Esm Lane, Abas Hadawey, Philip D. Howes

Mechanical Engineering

Nanoparticle-based lubricants, or nanolubricants, can exhibit superior tribological properties compared to unmodified base oils. However, these performance gains are highly dependent on the nanoparticle surface chemistry, particularly in maintaining stable colloidal dispersions. This study explores the influence of oleic acid (OA) and oleylamine (OAm) functionalization on the tribological and colloidal properties of CuO nanoparticles dispersed in an SAE 20W50 base oil. We present a hybrid optimization framework combining Response Surface Methodology (RSM) with Bayesian Optimization (BO) to identify the optimal OA to OAm ratio (OA–OAm) for CuO nanolubricants. Unlike prior studies that employed either RSM alone or trial-and-error approaches, this …

Advancing Real-World Implementation Of The Well Optimized Linear Finder (Wolf) High-Speed Atmospheric Turbulence Compensation Method, Timothy Evan Coon

Theses and Dissertations

This dissertation advances the real-world implementation of the Well Optimized Linear Finder (WOLF) method for high-speed Atmospheric Turbulence Compensation (ATC). Atmospheric turbulence introduces phase aberrations into optical wavefronts and degrades image quality in terrestrial imaging systems. Traditional phase diversity methods are computationally intensive and poorly suited to real-time operation. The WOLF method addresses these limitations through a novel, point-wise formulation of the optical transfer function (OTF) as a structured autocorrelation of the generalized pupil function (GPF). This formulation enables the estimation of phase aberrations at individual spatial coordinates with distributed computational complexity.

The research begins by developing a MATLAB-based simulation …

Soft Hexapod Robot With Tendon-Driven Continuum Legs For Internal Infrastructure Inspection, Setayesh Yavari

LSU Master's Theses

The need for robotic systems capable of operating in confined, hazardous, or complex environments has driven interest in soft and legged platforms for industrial inspection and structural integrity assessment. This thesis presents the design and fabrication of a tentacle-like, soft-legged hexapod robot, which uses six cable-stiffened, pre-curved, tendon-driven continuum robot (TDCR) legs. These biologically inspired legs are designed to offer a balance between compliance and control, enabling the robot to navigate unstructured terrains and potentially grasp cylindrical structures such as pipes. The design phase involved the development and comparison of multiple leg geometries using CAD modeling and finite element analysis …

An Engineering Solution For Fan Aeroacoustics Measurements Correction In A Non-Anechoic Testing Environment, Saad-Eldin Taha, Mohamed Y.Zakaria, Mohamed Abdelgaied, M.M. Bassuoni Prof. Dr.

Journal of Engineering Research

Abstract- Nowadays, acoustic signatures of daily used applications are to be minimized. The study of noise generated through aerodynamic interaction with moving bodies has passed through different phases since the early 50s, and this leads to the evolvement of many analytical, empirical and computational techniques in order to be able to estimate the emitted noise. Concerning fan blades, until now the researches are still going for a reliable method for noise estimation during the early phases of design which help in the development of blades with a lower aeroacoustic signature, the Brooks, Pope and Marcolini (BPM) model was chosen to …