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Full-Text Articles in Mechanical Engineering

Reconfigurable Python Autopilot Software For Rc Aircraft, Kate Doiron May 2025

Reconfigurable Python Autopilot Software For Rc Aircraft, Kate Doiron

Honors Theses

No abstract provided.


Ultrafast Laser Surface Structuring For Wettability Control On Copper, Akshay Arvind Nagvenkar May 2025

Ultrafast Laser Surface Structuring For Wettability Control On Copper, Akshay Arvind Nagvenkar

All Theses

Wettability is a crucial surface property influencing various phenomena, including heat transfer, cell adhesion, and corrosion. Engineering devices can achieve superior performance by precisely manipulating surface wettability. As a result, extensive research has focused on developing surfaces that exhibit either extreme water attraction (superhydrophilic) or strong water repellency (superhydrophobic). Tailoring surface wettability paves the way for numerous applications, such as drag reduction in marine vessels, controlled drug delivery, efficient water collection, advanced liquid transport systems, oil-water separation, anti-corrosion coatings, friction reduction, and self-cleaning materials. Ultrafast laser surface structuring is a promising approach for engineering multifunctional surfaces, effectively modifying material properties …


Reinforcement Learning For High-Dimensional Tradespace Exploration In Multi-Objective Optimization, Aaditya Kothavade May 2025

Reinforcement Learning For High-Dimensional Tradespace Exploration In Multi-Objective Optimization, Aaditya Kothavade

All Theses

Engineering design optimization often requires balancing multiple competing objectives while navigating complex, high-dimensional tradespaces. Despite significant advances in tradespace exploration techniques, current methods face critical challenges in efficiently navigating high-dimensional design spaces. As the number of design variables and competing objectives increases, traditional multi-criteria decision-making and optimization methods struggle to explore the vast solution space comprehensively. The curse of dimensionality exacerbates this issue, making it impractical to analyze all possible solutions and effectively identify trade-offs between objectives. Additionally, the computational complexity of high-dimensional spaces further complicates optimization, making exhaustive solution analysis infeasible. Traditional multi-objective optimization methods rely on static Pareto-front …


Stability Of Holes In Granular Raft, Plabon Kumar Saha May 2025

Stability Of Holes In Granular Raft, Plabon Kumar Saha

All Theses

A granular raft at an oil–water interface exhibits unique mechanical properties, including the ability to form and sustain stable holes. In this study, we experimentally investigate the formation, stability, and collapse dynamics of holes in particle rafts composed of micrometer-sized particles. Holes are created using a hollow cylinder, which generates a meniscus that inhibits particle motion, thus stabilizing the hole. Stable holes are formed when their size reaches a critical value, which depends upon the capillary length. The critical hole size does not depend upon the circularity of the hole. We show that capillary forces due to the presence of …


Micro Wind Turbine - Modelling And Testing, Mohammad Uzair Bhati May 2025

Micro Wind Turbine - Modelling And Testing, Mohammad Uzair Bhati

All Theses

The global energy demand continues to rise as people consume more electricity to power their personal electronics, electric vehicles, and consumer products such as outdoor tools. To generate renewable energy, large scale solar and wind farms continue to receive the most commercial attention. However, portable wind energy turbines have the potential to generate sufficient power for cell phones and other electronic devices. There are two types of wind turbines, horizontal and vertical axis each having their pros and cons. Vertical-axis wind turbines are the main focus of this thesis, with a reduction in their form factor or size and portable …


Developing Reduced Order Models For Gas Bubble Formation In Irradiated Metals Using Integrated Phase Field Modeling And Koopman Operator Theory, John M. Eggemeyer V May 2025

Developing Reduced Order Models For Gas Bubble Formation In Irradiated Metals Using Integrated Phase Field Modeling And Koopman Operator Theory, John M. Eggemeyer V

All Theses

Irradiation damage in materials is prevalent in nuclear components, posing significant risks in the safety and reliability of nuclear reactors. Phase field models offer a versatile framework for modeling irradiation damage in materials at mesoscales. Such high fidelity method has been used to model the formation of fission gas bubbles superlattice, a microstructure array occurs at certain irradiation conditions (dose, dose-rate, and temperature). To overcome the high computational cost of phase field modeling, Koopman operator theory is applied to create reduced order models, allowing for instantaneous simulations of fission gas bubble behaviors. These low fidelity models are integrated into machine …


An Experimental And Computational Study Of High-Temperature Creep Behavior In Fully Lamellar Titanium Aluminide Alloys, Karel M. Ziminsky May 2025

An Experimental And Computational Study Of High-Temperature Creep Behavior In Fully Lamellar Titanium Aluminide Alloys, Karel M. Ziminsky

All Theses

Titanium aluminide alloys have seen increased aerospace applications in recent years, especially in aircraft jet engines. They can offer benefits such as improved high-temperature strength compared to titanium alloys and reduced density compared to nickel alloys. These alloys also can exhibit high creep resistance due to their fully lamellar microstructure. These mechanical properties are desirable for components like turbine blades, where tight tolerances must be maintained for optimal performance. This research examines the high-temperature creep behavior of a fully lamellar two-phase titanium aluminide alloy, TNM® (Ti-43.5Al-4Nb-1Mo-0.1B), through experimental and computational methods. Scanning electron microscopy studies reveal the presence of large …


Tsunamigenesis On A Buoyant Granular Layer As A Model Of Ice Mélange In Ice-Choked Fjords, Nathan F. Reyner May 2025

Tsunamigenesis On A Buoyant Granular Layer As A Model Of Ice Mélange In Ice-Choked Fjords, Nathan F. Reyner

All Theses

Glacial calving events can often create destructive tsunami waves in ice-choked fjords in the arctic region, posing a threat to local inhabitants and damaging coastlines. Here the sea is covered by a polydisperse granular material called ice mélange, whose properties can affect the wave characteristics. To investigate the role of a buoyant granular layer, as a model of ice mélange, on tsunami generation, or tsunamigenesis, a series of laboratory experiments were conducted by collapsing a column of dense granular material into a body of water with a layer of buoyant particles distributed across the liquid surface. Experiments were performed over …


Mechanistic Insights Into Polymer-Assisted Graphene Exfoliation: The Roles Of Velocity, Adhesion, Cohesion, Temperature, Peeling Mode, And Edge Defect Via Coarse-Grained Molecular Dynamics, Linjiale Dai May 2025

Mechanistic Insights Into Polymer-Assisted Graphene Exfoliation: The Roles Of Velocity, Adhesion, Cohesion, Temperature, Peeling Mode, And Edge Defect Via Coarse-Grained Molecular Dynamics, Linjiale Dai

All Theses

Graphene exfoliation is a critical step in the fabrication of high-quality graphene

layers. However, the underlying fracture mechanisms remain poorly understood. In this

work, I employed coarse-grained (CG) molecular dynamics (MD) simulations to

investigate how factors such as interfacial binding energy, substrate cohesion, temperature,

peeling mode, and edge defects influence the outcome of the exfoliation process. To model

polymer-assisted mechanical exfoliation, I used a finite-size system in which multilayer

graphene (MLG) is sandwiched between two thin polymer films. Leveraging the

spatiotemporal efficiency of the CG model, I performed fifty simulation iterations per

parameter set and analyzed the results from a …


Precooling Ventilation Air For Hospital Operating Rooms And The Affects On Terminal Box Reheat, Joel F. Luke Jr May 2025

Precooling Ventilation Air For Hospital Operating Rooms And The Affects On Terminal Box Reheat, Joel F. Luke Jr

LSU New Orleans Theses and Dissertations

This study evaluates the impact of climate on the energy performance of two HVAC system configurations—AL1, a conventional air handling system, and AL2, which incorporates a pre-cooling coil and discharge air temperature (DAT) reset strategy. Using EnergyPlus simulations, each system was modeled across multiple U.S. cities representing a wide range of climate zones. Results show that AL2 significantly reduces plant energy consumption, with an average energy savings of 66.61\% compared to AL1. These savings were nearly evenly split between reductions in heating and cooling demands.

A weather normalization analysis using cooling and heating degree days (CDD65 and HDD65) revealed a …


Signal Modeling Of High Purity Germanium Detectors, Brooke Parker Thibodeau May 2025

Signal Modeling Of High Purity Germanium Detectors, Brooke Parker Thibodeau

Honors Scholar Theses

Pulse shape analysis can be used to analyze radiation incident on a semiconductor diode detector. Finite element analysis (FEA) can be used to simulate high purity germanium detectors with user-specified geometry, impurity concentration, and bias voltage. Subsequent streamline calculation can be used to conduct pulse shape analysis for single and multiple site gamma-ray interactions within the detector volume. Cross sections of the detector can be visualized by contour plots of the electric field, drift velocity magnitude, and collection time, as well as t30 and t90 rise-time values.


Experimental Study Of Process Parameter Effects On Internal Defects In Titanium Coaxial Wire-Based Laser Metal Deposition, Remy Mathenia, Braden Mclain, Todd Sparks, Frank Liou May 2025

Experimental Study Of Process Parameter Effects On Internal Defects In Titanium Coaxial Wire-Based Laser Metal Deposition, Remy Mathenia, Braden Mclain, Todd Sparks, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Wire-based laser metal deposition is an additive manufacturing process that can be used in the efficient manufacturing of complex structures. This paper utilizes a three-beam coaxial laser wire system to explore the effect of process parameters on the resultant deposition density. The reduction in or elimination of defects is important to the mechanical properties of the additively manufactured material and the widespread adoption of additive manufacturing processes. In this work, two-bead-wide walls were deposited under varying experimental conditions, including the traverse feed rate and workpiece illumination proportion. A method for calculating the bead pitch and layer height increment based on …


Graphics Processing Unit-Enabled Path Planning Based On Global Evolutionary Dynamic Programming And Local Genetic Algorithm Optimization, Junlin Ou, Ge Song, Yi Wang May 2025

Graphics Processing Unit-Enabled Path Planning Based On Global Evolutionary Dynamic Programming And Local Genetic Algorithm Optimization, Junlin Ou, Ge Song, Yi Wang

Faculty Publications

This paper presents a novel path planning method for real-time robotic path planning in a dynamic environment involving moving obstacles. It combines on a holistic platform a global approach to rapidly generate initial paths of prominent diversity and a heuristic approach to enable local path refinement for enhanced computational efficiency, exploration, and robustness. The global approach innovates a formulation that treats a path planning problem with a visibility graph as a Markov decision process and decomposes the process into many subproblems. A new evolutionary dynamic programming approach (EDP) is proposed to solve these subproblems in an iterative manner using …


Investigating The Feasibility Of Developing A Fully Solar-Driven Combined Cycle Design, Mazdak Gorji May 2025

Investigating The Feasibility Of Developing A Fully Solar-Driven Combined Cycle Design, Mazdak Gorji

LSU New Orleans Theses and Dissertations

This study explores the feasibility of a thermal solar-only combined cycle power plant, a concept rarely investigated despite its potential to outperform photovoltaic systems in energy efficiency. Unlike typical hybrid models that use solar energy as a supplement to fuel, this research focuses on a solar-only system that operates a true Brayton-Rankine combined cycle for continuous 24/7 power generation. The study established an efficiency benchmark, comparing eighteen solar generation scenarios across different storage and power block configurations to assess whether the concept was worth pursuing, which it proved to be. Following this, the research focused on simulation, validating ThermoFlex software …


Storytelling In Undergraduate Engineering Courses As Inclusive Curriculum: Improving Students’ Sense Of Belonging, Identity, And Persistence, Brooke Heller May 2025

Storytelling In Undergraduate Engineering Courses As Inclusive Curriculum: Improving Students’ Sense Of Belonging, Identity, And Persistence, Brooke Heller

Boise State University Theses and Dissertations

The engineering field experiences high attrition rates and a historical lack of diversity in the United States. Sense of belonging and identity have been shown to impact persistence, especially for people from historically marginalized communities. This three-paper dissertation is focused specifically on this phenomenon in academia and methods of contributing to improving and progressing conditions. To pivot to a new paradigm in which people from diverse backgrounds feel welcome and valued, there is a need for more inclusive practices in the field, particularly in the form of curriculum in academia. Inclusion has been shown to improve outcomes for students from …


Exploring Metal Additive Manufacturing In Martian Atmospheric Environments, Zane Mebruer May 2025

Exploring Metal Additive Manufacturing In Martian Atmospheric Environments, Zane Mebruer

Mechanical Engineering Undergraduate Honors Theses

On-surface manufacturing is key to the success of a planetary colonization, especially that of Mars. However, traditional subtractive manufacturing processes are equipment, energy, and material intensive, meaning novel additive manufacturing (AM) processes must be pursued for this end. Selective laser melting, one of the most effective and versatile AM methods, would be incredibly beneficial to a Martian mission but requires an artificial argon atmosphere to create effective parts. The purpose of this study was to examine if carbon dioxide, the gas that makes up over 95% of Mars’ surface atmosphere, would be a sufficient substitute for argon in SLM fabrication. …


Causes And Contributing Factors In General Aviation Fixed-Wing Stall And Spin Accidents, Lauren Westfall May 2025

Causes And Contributing Factors In General Aviation Fixed-Wing Stall And Spin Accidents, Lauren Westfall

Mechanical Engineering Undergraduate Honors Theses

General Aviation operations are all civil aviation operations excluding commercial airline operations and cargo transport. General Aviation accidents comprise approximately 94% of all aviation accidents in the United States annually. Stall and spin accidents are the third most common causes of fatal General Aviation accidents, accounting for 7.28% of such accidents in 2013–2022. The National Transportation Safety Board investigates and records all General Aviation accidents in the United States. Using the National Transportation Safety Board’s accident database, I investigated stall and spin accidents between 2013 and 2022 to find (1) the most common phases of flight where stall and spin …


Agent-Based Modeling For Faulty System Analysis, Jayden G. Hamilton May 2025

Agent-Based Modeling For Faulty System Analysis, Jayden G. Hamilton

Mechanical Engineering Undergraduate Honors Theses

Numerous approaches exist for computational modeling of complex, dynamic systems. One particular option is the use of agent-based modeling, which simulates the behavior of numerous autonomous agents interacting with each other and with the system at large. Current agent-based modeling research has largely focused on studying the system level behavior of a model, as this is generally the main concern for any real world application. However, the characteristics and behaviors of agents deserves consideration as well. The issue with this area of interest lies in the fact that the agent data cannot be as quickly obtained and analyzed as system …


A Labview-Based Open-Source Data Acquisition Program For Acoustic Emission Sensing, Harrison Greene May 2025

A Labview-Based Open-Source Data Acquisition Program For Acoustic Emission Sensing, Harrison Greene

Mechanical Engineering Undergraduate Honors Theses

Acoustic emission sensing is a growing field of analysis and testing that benefits from its non-destructive nature, enabling operators to detect faults, the severity of impacts, the propagation of cracks, and much more without damaging the system being tested. However, the use of proprietary software to collect, analyze, and display data hinders the field, as access to this crucial information makes consistent and in-depth data analysis impossible. To this end, this paper details an open-source code made in the programming language LabVIEW for the express purpose of allowing the user to have full access to all data and fully customize …


Using Optical Dielectrophoresis For Microbead And Cell Manipulation, Leigh K. Smith May 2025

Using Optical Dielectrophoresis For Microbead And Cell Manipulation, Leigh K. Smith

Mechanical Engineering Undergraduate Honors Theses

Dielectrophoresis is a common method used to manipulate particles on the microscopic scale. Optically Induced Dielectrophoresis or ODEP is the specific method used in this research. All experiments were conducted in Dr. Tung’s Micro and Nano Systems lab at the University of Arkansas’ ENRC. An ODEP system was created in the lab for manipulating microbeads (6-10 micrometers (μm) in diameter) and E. coli cells (1-2 μm in diameter).

Experiments were performed on the microbeads to see how changing the parameters of the device affects the force caused by ODEP on the beads. The parameters that could be changed in the …


Optimal Parameters For Electrode Free Local Anodic Oxidation Lithography, Maxwell C. Cleveland May 2025

Optimal Parameters For Electrode Free Local Anodic Oxidation Lithography, Maxwell C. Cleveland

Mechanical Engineering Undergraduate Honors Theses

Dr. Steve Tung’s research lab is developing a device for sequencing DNA strands. A key component of this device is a nano sensor fabricated using monolayer graphene. To create the sensor, the graphene must be precisely patterned. Graphene, a single layer of carbon atoms, is an ideal material for detecting electrical signals from DNA bases due to its excellent conductivity.

The current fabrication method uses Atomic Force Microscopy (AFM) in combination with Electrode-Free Local Anodic Oxidation (LAO) lithography. While AFM is typically employed for nanoscale imaging, pairing it with LAO lithography enables the patterning of graphene into nanoribbons capable of …


Adjustable Dynamometer Motor Mount, Garrett Carson Ng, Elijah Siegel Reuven, Ethan Fong, Daniel Larimer May 2025

Adjustable Dynamometer Motor Mount, Garrett Carson Ng, Elijah Siegel Reuven, Ethan Fong, Daniel Larimer

Mechanical Engineering

The Cal Poly Electrical Engineering Department and sponsor Dr. Dolan needs a manufacturable motor fixture that securely aligns motors of various sizes with dynamometers. Previous lab motor fixtures could not accommodate motors of different sizes, making precise alignment between motors and dynamometers time-consuming and unreliable. Our team developed a modular, manufacturable fixture capable of aligning various motor sizes quickly, accurately, and securely, enhancing lab consistency and usability.


Effects Of The Gravity Gradient On The Path Of 1i/‘Oumuamua, Hannah R. Richardson May 2025

Effects Of The Gravity Gradient On The Path Of 1i/‘Oumuamua, Hannah R. Richardson

Honors Theses

In October 2017, the asteroid 1I/’Oumuamua first passed into viewing range [1]. The asteroid is notable for being the first interstellar object to enter the solar system. 1I/’Oumuamua was also unusual in its geometry; it is thought to have an aspect ratio of 6:1 and a length of approximately 400 m [2] [3]. The asteroid was observed to experience a non-Keplerian acceleration estimated to be on the order of 1⇥10−6 m s2 . Several theories have been proposed for the cause of this acceleration, all of which are non-gravitational in nature: volatile outgassing, photon pressure, and solar winds [1][4]. However, …


Deciphering And Translating Bioinspired Structures For Engineering Materials Design Via Computational Modeling And Machine Learning, Zhangke Yang May 2025

Deciphering And Translating Bioinspired Structures For Engineering Materials Design Via Computational Modeling And Machine Learning, Zhangke Yang

All Dissertations

Nature has evolved extraordinary structural materials—such as nacre, bone, and the mantis shrimp’s dactyl club—that achieve remarkable combinations of strength, toughness, and impact resistance. These properties arise from sophisticated synergies between structure and composition. Inspired by these biological systems, this dissertation presents a comprehensive investigation into bioinspired materials, uncovering fundamental mechanisms and providing guidance on designing materials with superior mechanical properties.

This dissertation begins by examining the "brick-and-mortar" structure of nacre, which informs the design of layered polymer-graphene nanocomposite films. Using coarse-grained molecular dynamics simulations, I elucidate mechanisms of dynamic wave propagation and energy dissipation in these systems, providing critical …


The Trials And Tribulations Of Building An Ebike From Recycled Parts, Olivia Conrady May 2025

The Trials And Tribulations Of Building An Ebike From Recycled Parts, Olivia Conrady

Senior Honors Projects

The United States is far from being “walkable” in most suburban areas. Though public transportation has grown in its infrastructure in some large cities, it is far from sufficient. As a result of this, millions of people drive their cars every single day -- a practice that is unsustainable and becoming an increasingly evident issue. One possible solution that has become popular is the use of electric bicycles, since they are less physically taxing than a normal bike and allow for quicker transport. Though electric bicycles have been on the rise, they are still well outside of many people’s budget, …


Uncertainty Quantification Of Turbulent Premixed Flames, David L. Brown May 2025

Uncertainty Quantification Of Turbulent Premixed Flames, David L. Brown

Honors Theses

This thesis presents an uncertainty quantification (UQ) study of turbulent premixed flames, focusing on the impact of uncertainties in operating conditions on the normalized consumption speed. Namely, temperature, pressure, and equivalence ratio are the operating conditions that are under study. Due to significant computational demands associated with direct MC methods for UQ, surrogate modeling techniques including Polynomial Chaos Expansion (PCE), Stochastic Collocation (SC), and Gaussian Process (GP) are evaluated based on efficiency and accuracy. Through this study, PCE is identified as the optimal surrogate model due to its accuracy and significantly reduced computational costs. PCE is subsequently applied to investigate …


A Simplified Thermal And Battery Model For Off-Grid Solar Air Conditioning In Florida’S Hurricane Context, Steven A. Sanford May 2025

A Simplified Thermal And Battery Model For Off-Grid Solar Air Conditioning In Florida’S Hurricane Context, Steven A. Sanford

Honors Theses

Florida’s hurricane-prone climate often leaves residents without power and at risk of dangerous indoor heat conditions. This thesis examines whether an off-grid, solar-powered air conditioning system can feasibly maintain safe indoor temperatures over a one-week outage period during peak hurricane season. A simplified, lumped-capacitance thermal model and an energy-based (Coulomb-counting) battery state of charge (SoC) approach were developed in MATLAB to simulate a DC-powered air conditioner (the DC48 unit) in a single-zone space. Historical weather and solar irradiance data from Vero Beach, Florida, represent the hot and humid conditions typical of post-hurricane scenarios. The model uses an on/off plus deadband …


An Integrative Approach To Einstein’S Field Equations Of General Relativity For High School Students, Christina M. Aintablian May 2025

An Integrative Approach To Einstein’S Field Equations Of General Relativity For High School Students, Christina M. Aintablian

Senior Honors Theses

Einstein’s Field Equations form the foundation of the theory of General Relativity, describing the interdependence of mass-energy and spacetime curvature, where curvature gives rise to gravity. However, the complexity of these equations makes them difficult for high school students to grasp. The mathematical framework of General Relativity is introduced step by step, beginning with relative motion and culminating in a discussion of complex phenomena that challenge modern physics. Each explanation intertwines core concepts of relativity with pre-established mental models to enhance learning. Through the use of figures, analogies, narratives, and thought experiments, a structured framework is developed to make relativity …


Baja Sae Brakes, Carson Moore, Jaedyn Michael Imhoff, Will Duncan, Matthew Shaffer May 2025

Baja Sae Brakes, Carson Moore, Jaedyn Michael Imhoff, Will Duncan, Matthew Shaffer

Mechanical Engineering

Historically, the Cal Poly Racing Baja SAE has produced a braking system that has proven unreliable and barely passes competition rules and inspections, leading to ill performing and unsafe brakes. The goal of this project is to produce a system and documentation that meets the requirements provided by Cal Poly Racing Baja SAE. The final design includes a transient braking model of the vehicle to set system requirements, universal custom front and rear calipers modified from “Cal Poly BSAE Custom Brake Caliper Senior Project”, and a revamped hydraulic harness. Leaning on the team’s previous work and modifying the custom calipers …


Finding Groundwater With Electricity: Research And Testing Of An Electro-Resistive Ground-Surveying Device For Use In Well-Drilling Applications, Samuel L. Heath May 2025

Finding Groundwater With Electricity: Research And Testing Of An Electro-Resistive Ground-Surveying Device For Use In Well-Drilling Applications, Samuel L. Heath

Senior Honors Theses

A custom-built electro-resistive water detection device is tested under various conditions to evaluate its overall performance and sensitivity to changing variables. The tests, designed to assess accuracy and precision, revealed that the prototype exhibits high reliability (~ 99%) for both Schlumberger and Wenner arrays across different electrode spacings and soil conditions. Moreover, the measured resistivity values from the soil tests aligned with established literature ranges for each soil type. The device also showed the ability to consistently detect changes in soil water content by producing measurable variations in resistivity. At a total cost of $181, this prototype can serve as …