Mechanical Engineering Commons^™

Portable Low-Cost Spectrophotometer, Ian Bozovich

Maseeh Summer Undergraduate Research Experience

The goal of this project was to build a spectrophotometer that is: Inexpensive (~$300 USD), portable (4” L x 4” W x 2.5” H), capable of producing replicable results, and capable of producing results that are comparable to a higher cost spectrophotometer (~$3000+ USD). Six samples and a blank were prepared by making solutions containing various concentrations of vitamin B12. Measurements of light intensity across the visible spectrum were taken for each sample and used with the Beer-Lambert Law to obtain an absorbance spectrum for the various concentrations of vitamin B12. Results indicate that this device could be an excellent …

Comparing Two Fast-Response Air Pollution Dispersion Modeling Tools For Emergency Management Scenarios, John Abed

Maseeh Summer Undergraduate Research Experience

The oversight of the research is conducted by the Healthy Buildings Research Lab (HBRL), which utilizes two dispersion modeling tools for emergency management, namely ALOHA and QUIC Plume/URB. This experiment aims to explore the key differences between the two and to gain a deeper understanding of their strengths and weaknesses. For this project, using 2 different software programs to show the true dangers of what could happen if an Earthquake were to strike. We’re focused on comparing emissions from a single tank and comparing across ALOHA and QUIC. QUIC gave a better representation of what would happen if a leak …

Internally Stowed, Radially Deployed Radiator Panels For Passive Cubesat Thermal Control, Josh R. Cannon, Kyle N. Havey, Noah S. Housley, Rydge B. Mulford, Brian D. Iverson

Faculty Publications

CubeSats experience significant thermal loads due to solar irradiation and the dissipation from electrical components. The high heat dissipation per unit volume can lead to mission failure if not properly managed. Deployable radiators that are externally stowed and passively actuated in response to changes in CubeSat temperature have been explored as a viable solution. This work describes a radially deployed fin array that is stowed within the CubeSat body when the required heat dissipation is low and passively deploys when the required heat dissipation is high. Internal stowage improves thermal transport to the deployable fins and minimizes heat loss when …

Drop Dynamics During Condensation On Superhydrophobic Surfaces In Vapor Shear Flow, Shaur Humayun, R. Daniel Maynes, Julie Crockett, Brian D. Iverson

Faculty Publications

Accurate models for predicting drop dynamics, such as maximum drop departure sizes, are crucial for estimating heat transfer rates during condensation on superhydrophobic (SH) surfaces. Previous studies have focused on examining the heat transfer rates for SH surfaces under the influence of gravity or vapor flowing over the surface. This study investigates the impact of surface solid fraction and texture scale on drop mobility in a condensing environment with a humid air flow. Experiments recorded condensation with varying surface feature sizes from micro- to nano scale under different flow rates. Video analysis detected the drop-size distribution and maximum drop departure …

Origami Folding Pattern Development For Gossamer 18 Structures, Larry L. Howell, Ivy Running, Carolina Wright, Robert J. Lang, Spencer Magleby

Faculty Publications

Gossamer structures for satellites are large, thin deployable structures that are attractive for space applications because they can be stowed compactly for transportation and deployed to have large functional surface areas. Reflectarray antennas, in particular, are candidates for gossamer structures because they can be realized on thin membranes. However, the efficiency of reflectarray antennas decreases with any deviations from a flat plane, including those induced by plastically deformed creases. Rolling membranes can prevent some plastic deformation, but requires relative slipping between layers that are rolled together. In this work, we describe, analyze, and demonstrate two rolled configurations for deployable gossamer …

A Generalized Coherence Framework For Quantifying Input Contributions In Multi-Input Systems With Correlated Or Uncorrelated Inputs, Nolan H. Howes, Matthew S. Allen, Dario Farina, Steven Knight Charles

Faculty Publications

In multi-input systems, it is often necessary to quantify the contribution of each input to an output. Such contribution analysis is frequently performed using coherence. However, when correlation is present between inputs, existing coherence measures do not accurately quantify the contribution of individual inputs, except in special cases. Here we propose an expanded coherence framework that enables contribution analysis in any multi-input system, regardless of input correlation. We bridged the gap by defining three new coherence measures: component, excluded, and isolated coherence. Component coherence is an intermediate measure that decomposes measured output power into components attributable to inputs directly vs …

A Biphasic Microstructural Model Of Skeletal Muscle To Study Structure-Function Mechanisms Under Multiaxial Tensile And Compressive Conditions, Benjamin Wheatley, Minhaj U. Bhuiyan, Sabrina S. Lorza, Kevin M. Moerman, Pierre-Yves Rohan

Faculty Journal Articles

No abstract provided.

Multiphysics Modeling Of Solid Oxide Fuel Cells For Gradient Minimization And Inductive Loop Analysis In Impedance Spectroscopy Using Machine Learning-Based Microstructural Property Estimation, Muhammad Usman Khan

College of Graduate Studies: Theses & Dissertations

Solid oxide fuel cells have significant advantages in renewable energy utilization due to their high efficiency, fuel flexibility, and low emissions. However, despite the numerous efforts of technology, thermal and current density gradients and impedance behavior fluctuations are still causing performance degradation. A combined computational framework that integrates machine learning and three-dimensional Multiphysics modeling is needed to investigate and optimize the performance of solid oxide fuel cells. A machine learning model, trained on synthetic microstructure data by percolation analysis, is used to predict important microstructural parameters like triple phase boundary density and geometric tortuosity. These are then employed in a …

Viscoelastic Property Analysis Of A Magnetorheological Elastomer Micropump For Insulin Delivery In Type 1 Diabetes, Victor Buitimea

College of Graduate Studies: Theses & Dissertations

Over two decades, there has been a significant rise in awareness regarding Type 1 Diabetes (T1D), leading to a deeper comprehension of numerous variables, including hereditary factors, patterns of occurrence, and health challenges. According to the Type 1 Diabetic Index, around 8.7 million people worldwide are affected by this chronic autoimmune illness marked by a lack of insulin and hyperglycemia. The introduction of artificial pancreas systems could save more than half a million patients by 2040. Despite the availability of various insulin delivery technologies that are offered to diabetic patients, many still are skeptical of this modern system. The issues …

Effect Of Alloying Additions On Austenite Refinement In Nickel-Alloyed Ductile Cast Irons, Adnan Adib Aahamed

College of Graduate Studies: Theses & Dissertations

The benefits associated with the application of ductile irons are significantly attributed to the control of microstructures, with refinement of austenitic matrix during solidification playing a significant role. Nickel alloyed ductile irons are attractive due to their potential for high ductility and suitability for potential high-temperature applications with stable austenitic microstructure. Refinement of austenite grain structure is thus important to enhance the mechanical properties of the alloyed ductile iron. This research investigates the impact of in-mold additions of different alloying elements on the austenite morphology and grain refinement of nickel-alloyed ductile iron along with the associated mechanical properties. A hypoeutectic …

Enhancing The Mechanical Properties Of Sla 3d-Printed Bio-Resin From Linseed Oil Using Cellulose And Lignin Biopolymers, Chukwunonso A. Ikedionu

College of Graduate Studies: Theses & Dissertations

Abstract

This research explores the development of bio resin from linseed oil by the process of epoxidation and acrylation to produce acrylated epoxidized linseed oil (AELO). Lignin and cellulose biopolymers were added as reinforcement at varying weight fractions of 1 wt.%, 2.5 wt.%, and 5 wt.%, and their mechanical performance was compared against pure AELO. The formulations were printed using an Elegoo SLA 3D printer to create standardized test specimens like tensile bars, compression cylinders, and hardness blocks, which were all prepared according to the ASTM testing standard.

The results indicate that reinforcement effects depend on both filler type and …

Dynamic Beamforming And Array Shape Estimation, Nicholas Ryan Costick

Open Access Master's Theses

The accurate estimation of towed sonar array shapes during complex maneuvers is a critical challenge affecting beamforming and target localization performance. When underwater arrays experience sharp turns or rapid movements, sensor positions become difficult to track precisely, negatively impacting the reliability of beamforming methods. This thesis addresses the issue of dynamic array shape uncertainty, motivated by operational challenges faced by the Navy.

A maximum-likelihood estimation (MLE) method is developed to simultaneously estimate the array shape and field directionality (spatial spectrum) during maneuvers. The proposed solution expands upon previous research, specifically the dynamic spatial spectrum estimation techniques described by Rogers and …

Experimental Validation Of Model Predictive Control For Roll Attenuation Of Scale Model Barge In Beam Sea Conditions, Callum Robbins

Open Access Master's Theses

Floating offshore wind turbines (FOWTs) are the next great frontier in the offshore energy world. However, for these machines to be safe, effective, and reliable, they must be stable. In this thesis, an active control strategy is developed that uses future wave information and model predictive control to attenuate wave induced motions of a floating platform, such as a FOWT. The future wave information is provided by a wave reconstruction and prediction (WRP) algorithm which allows for wave events to be calculated faster than real-time. This wave information is provided to a nonlinear model predictive controller (NMPC) that uses a …

Accurately Constituting Robust Interfaces For High-Performance High-Energy Lithium Metal Batteries, Kevin V. Carballo, Meetesh Singh, Xiangbo Meng

Mechanical Engineering Faculty Publications and Presentations

High-energy lithium metal batteries (LMBs) have received ever-increasing interest. Among them, coupling lithium metal (Li) with nickel-rich material, LiNi_xMn_yCo_zO₂ (NMCs, x ≥ 0.6, x + y + z = 1), is promising because Li anodes enable an extremely high capacity (∼3860 mA h g⁻¹) and the lowest redox potential (−3.04 V vs. standard hydrogen electrode), while NMCs can achieve a much higher capacity of ∼200 mA h g⁻¹ and lower cost than those of LiCoO₂. However, the resultant Li‖NMC cells have been hindered from commercialization due to a …

Safety And Sustainability In The Domestic Ferry Sector : A Pci Framework For Esg-Aligned Maritime Governance, Mirza Zeeshan Baig

World Maritime University Ph.D. Dissertations

The domestic ferry sector is a significant component of maritime transportation. It strengthens social ties, supports economic growth and connects communities. Despites its importance, this industry faces ongoing challenges. These include fragmented governance, operational adequacies, safety risks and environmental concerns. The study deals with these issues by combining a systems-based approach with governance and change management theories. It examines the interplay between human, technical and organizational aspects. The study integrates the rule-based and rights-based maritime governance along with the Lewin’s three stage change management model (Unfreeze, Change, and Refreeze).

At the core of the study is the development of a …

Mobile Robot Configured To Determine Human Arm Stiffness During Overground Interaction, Sambad Regmi, Yun Seong Song

Patents

A mobile robot system and method for determining the stiffness of a human arm while moving with a user during overground interaction as the user holds the robot's handle and exchanges forces with it. A mobile base moves with the user, a robot arm interacts with the user, and a controller determines the stiffness. The robot arm includes servomotors driving a linkage mechanism, an end effector including the handle supported by the linkage mechanism, and a force transducer measuring a force applied by the user to the handle. The controller causes the robot arm to generate a force perturbation at …

Ground Testing Of A Magnetic-Electrostatic Separation System For Lunar Regolith Beneficiation, Peter Bachle, Charles Wood, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han

Materials Science and Engineering Faculty Research & Creative Works

The separation of lunar regolith by mineral composition and size category is useful forin-situ resource utilization (ISRU). The research presented herein discusses the designing and development of equipment that has the potential to separate lunar regolith into aluminum, iron-titanium, and magnesium-iron ores. Along with the metal ore separation, this equipment shows the potential to separate regolith by size categories. The combined effect of these separation methods generates output that is valuable to subsequent use in metal and oxygen extraction, additive manufacturing, and regolith sintering processes. The designed equipment uses a dual-strength magnet system with N42 and N52 neodymium magnets for …

Controlling Nitrogen Pickup During Induction Melting Of Ultrahigh-Strength Cr-Ni-Mo-V Steels, Kingsley T. Amatanweze, Viraj A. Athavale, Mario F. Buchely, Laura N. Bartlett, Ronald J. O'Malley, Daniel M. Field

Materials Science and Engineering Faculty Research & Creative Works

Nitrogen pickup during air induction melting can result in porosity and a loss of fracture toughness in ultrahigh-strength quenched and tempered steel castings. Nitrogen atoms are easily adsorbed into liquid steel upon exposure to the air, and argon shrouding alone has limited effectiveness. Previous studies have shown that proper charge sequencing and maintaining a high amount of dissolved oxygen in the melt prior to tapping and deoxidation can limit nitrogen pickup in the melt. In the current study, the effect of melt practice and charging procedure on nitrogen pickup was studied as a function of hold time in a series …

Parametric Analysis Of Water Jet Descaling Efficiency Of Reheated Continuously Cast Thin Slab, Tochukwu P. Ojiako, Mario F. Buchely, Simon Lekakh, Ronald J. O'Malley, Richard Osei, Taha Tayebali

Materials Science and Engineering Faculty Research & Creative Works

Efficient oxide scale removal is critical for maintaining surface quality and process efficiency in steel manufacturing. This study optimizes water jet descaling by evaluating the performance of flat and rotary jet nozzles under varying process parameters. Using a combined approach of experimental analysis and computational fluid dynamics, it investigates the influence of pressure (138–275 bar), lead angle (0°, 15°, 25°), working distance (50–100 mm), and spray angle (15°–25°) on descaling efficiency. Findings indicate that flat jet nozzles achieve superior performance at short working distances due to concentrated impact forces, while rotary jet nozzles sustain efficiency over extended distances through dynamic …

Effect Of Gating Design On Filling And Inclusion Control In An Al-Killed Cr-Mo-Ni Steel, Kingsley T. Amatanweze, Koushik Balasubramanian, Soumava Chakraborty, Viraj A. Athavale, Mario F. Buchely, Laura N. Bartlett, Ronald J. O'Malley, Daniel M. Field, Krista R. Limmer, Katherine M. Sebeck

Materials Science and Engineering Faculty Research & Creative Works

The effect of gating system design on the inclusion population and size distribution in an aluminum-killed low-alloy advanced high strength steel casting was studied. A mold with four different gating systems: pressurized and non-pressurized with side risers, naturally pressurized with a side riser, and naturally pressurized with a top riser, was designed using computational fluid dynamics and solidification software. The design allowed inclusion populations in castings produced with each gating system to be compared during the same pouring event. Samples taken from different positions just below the top surface of each casting were analyzed using an SEM/EDS system with automated …

Comparison Of Cnn And Lstm Networks On Human Intention Prediction In Physical Human-Robot Interactions, Khosro Ghorbani Zadeh, Niloofar Zendehdel, George L. Holmes, Keyri Moreno Bonnett, Amy Costa, Devin Michael Burns, Ming-Chuan Leu, Yun Seong Song

Psychological Science Faculty Research & Creative Works

Advancements in robotics and AI have increased the demand for interactive robots in healthcare and assistive applications. However, ensuring safe and effective physical human-robot interactions (pHRIs) remains challenging due to the sophistication of human motor communication and intent recognition. Traditional physics-based models struggle to capture the dynamic nature of human force interactions, limiting robot adaptability. To address these limitations, neural networks (NNs) have been explored for force-movement intention prediction. While multi-layer perceptron (MLP) networks show potential, they struggle with temporal dependencies and generalization. Long Short-Term Memory (LSTM) networks effectively model sequential dependencies, while Convolutional Neural Networks (CNNs) enhance spatial feature …

From Spark To Wildfire: Predicting Wildfire Origins And The Efficacy Of “Fire Safe” Cigarettes In California Grasslands, Trevor Blackwell Haltermann

Cal Poly Humboldt theses and projects

As wildfires in North America increase in size and frequency, the societal impacts become greater as well. With greater risk and high fire suppression costs it is pertinent to improve fire investigation methods and limit the potential for human caused ignitions. Two distinct studies were carried out to assess the accuracy of fire pattern indicators and the efficacy of “fire safe” cigarette technology in lowland grass fuel types in California. The first study utilized 24 experimental small-scale fires within a wind tunnel to examine the accuracy of microscale fire pattern indicators and the factors that influence the accuracy of predictions …

Integrating Machine Learning And Symbolic Regression For Predicting Damage Initiation In Hybrid Frp Bolted Connections, Sherif Sorour

Mechanical Engineering

No abstract provided.

Ease Of Product Disassembly Through A Systematic Structured Time-Based Design For Disassembly Methodology, Emeka S. Igwe

College of Graduate Studies: Theses & Dissertations

This research introduces a systematic time-based design for disassembly (DfD) framework aimed at optimizing product disassembly by addressing important features like liaisons between components in product, component accessibility and the overall modularity of the product. This study specifically covers electromechanical and mechatronic systems in both household and industrial setup, identifying their disassembly challenges and high value pointers for improvement. The methodology involves using a design for disassembly framework called LeanDfD in carrying out a holistic disassembly process and evaluating quantitative metrics like disassembly time and complexity and suggesting further redesign strategies to minimize disassembly time and cost. Adopting this systematic …

Ranking Of Non-Destructive Testing Methods For Ductile Iron Castings For Industry 4.0, Michael W. Jones

College of Graduate Studies: Theses & Dissertations

Non-destructive testing techniques provide a unique solution to provide quality assurance of parts rapidly and efficiently without altering the functional properties of the workpiece. The metal casting industry requires an elevated level of quality assurance, as castings are critical components to several industries. The wrong selection of non-destructive testing methods could increase production costs, quality costs, and potentially permit non-conforming castings to enter the market. The aim of this research is to develop a ranking model for non-destructive testing techniques for ductile iron castings within the context of the fourth industrial revolution. The ranking model analyzes the effectiveness of the …

Pulsed Arc Additive Manufacturing Of A Functionally Graded Er2209 Duplex Stainless Steel And Hsla-100 Structure: Morphology, Characterization, And Mechanical Performance, Stevens G. Hill Jr

College of Graduate Studies: Theses & Dissertations

Wire arc additive manufacturing is a process well suited to the efficient production of large structures. Duplex stainless steel exhibits high corrosion resistance and good strength which can be highly beneficial for industrial use. However, its use is limited due to its cost and complexity in controlling microstructure to achieve desired properties. In many cases, it can be highly beneficial to manufacture a component which uses specialty steel grades such as duplex stainless steel only where necessary, and utilizes more affordable, commonly available steels for reinforcement or bulk structural support. A functionally graded material satisfies these requirements by providing a …

A Finite Volume-Based Approach For Modeling Hyperbaric Oxygen Therapy For Healing Chronic Wounds, Cade M. Layser

College of Graduate Studies: Theses & Dissertations

The current number of people in America with diabetes is approximately 38.4 million, that population is expected to rise to 54.9 million by 2030. Chronic wounds, which are characterized by impaired or stalled healing, are commonly associated with diabetes. These wounds if not treated properly can cause significant complications such as sepsis, infection, and gangrene which can lead to limb amputation or death of the patient. Limb amputations can be a large financial burden and significantly reduce the patient’s quality of life. The timely and efficient treatment of chronic wounds is essential to prevent adverse patient outcomes. Hyperbaric Oxygen therapy …

Defect Detection In Extrusion-Based Bio-Printed Constructs Using Video-Based Vibration Analysis, Md Anisur Rahman

College of Graduate Studies: Theses & Dissertations

Bio-additive manufacturing has emerged as a transformative advancement in biomedical engineering, enabling the fabrication of complex biological structures. However, maintaining the precision and quality of printed constructs remains a significant challenge, particularly in applications such as bioprinted organ transplants. Among the key factors affecting structural integrity, dimensional inconsistencies and interlayer defects present major obstacles, potentially compromising mechanical stability and functionality. This study explores the detection of defects caused by variations in dimensional accuracy and layer-to-layer adhesion. To address these challenges, a video-based motion estimation technique is employed as a non-contact and non-destructive evaluation method. Traditional approaches, such as contact-based and …

Synthesis And Processing Of Co-Axial/Tri-Axial Multi-Layered Nano-Particles, Jannatul Ferdaus

College of Graduate Studies: Theses & Dissertations

Electro-spraying has been used as an effective processing method of nanoparticle fabrication for the application of targeted drug delivery. The study demonstrates the feasibility of a non-conventional triaxial electro-spraying setup for multi-layered nano-drug fabrication and proposes optimized parameters. Two different drugs, XAV939 and Dextran 40000, were used to study the process parameters (voltage and solution concentration) of coaxial electro spraying. The particle size of Dextran-PCL was an average of 166.3 nm for PCL-Dextran at 32.5 kV and 18-hour sonication. The SEM analysis and UV-spectrum showed the encapsulation of Dextran with PCL, though the in vitro study in mice after 24 …

Experimental Study Of Deformation Behavior For A Novel Elastohydrodynamic Seal For Supercritical Carbon Dioxide Power Cycles, William A. Adams

College of Graduate Studies: Theses & Dissertations

Supercritical carbon dioxide (sCO₂) Brayton cycles are a strong contender for future power generation systems due to their high thermal efficiency and compact nature. Sealing is one of the key challenges presented by such systems that has a direct impact on the system's overall efficiency. This research is the first experimental study to investigate the deformation behavior of an elastohydrodynamic (EHD) seal made from bearing-grade polyether ether ketone (PEEK). A testing apparatus was developed to integrate four strain gauges positioned along the seal to quantify the deformation occurring up to pressures of 13 MPa. Mass flow rate measurements …