Engineering Commons^™

Corrosion Mitigation And Monitoring Of Bridge Tendons And Failure Forecasting Of Wastewater Force Mains, Stanley Chike Agbakansi

USF Tampa Graduate Theses and Dissertations

Corrosion remains a significant threat to civil infrastructure, resulting in costly repairsand potential structural failures. This dissertation addresses three critical aspects of corrosion: mitigation and monitoring of post-tensioned bridge tendons, and failure forecasting of wastewater force mains due to internal corrosion.

First, the research investigates the effectiveness of corrosion inhibitors (CIs) applied via pressure injection (impregnation) in post-tensioned tendons. The protective mechanisms and long-term performance of various inhibitors were evaluated to identify the most effective formulations. Among the tested inhibitors, MCI-2020 — a water-based, migratory, mixed-type corrosion inhibitor — demonstrated the most promising results, showing excellent corrosion protection while preserving …

Tailoring Gel Polymer Electrolytes For Advancing Quasi-Solid-State Batteries, Linrui Duan, Juchen Zhang, Mataz Alcoutlabi, Hongtao Sun

Mechanical Engineering Faculty Publications

Gel polymer electrolytes (GPEs) have attracted considerable attention due to their advantageous properties, such as uniform lithium deposition, stable solid electrolyte interphase (SEI) formation, nontoxicity, nonflammability, and leak-proof characteristics. In this study, a polyvinylidene fluoride hexafluoropropylene copolymer (PVDF-HFP)-based gel polymer electrolyte is synthesized via photo-polymerization, with a focus on examining the effects of curing time on electrolyte performance. The findings reveal that UV irradiation conditions significantly influence key material and electrochemical properties of the GPEs, including lithium-ion transference number, ionic conductivity, crystallinity, morphology, and liquid electrolyte uptake. Notably, the GPE cured for 120 s exhibited optimized performance, achieving an ionic …

Empowering Engineering Students To Become More Effective And Self-Regulated Learners Through Course-Integrated Learning Strategies Intervention: A Pilot Study In A Solid Mechanics Course, Huihui Qi, Richard Eugene Vallejo Jr., Changkai Chen, Minju Kim, Alex M. Phan, Marko Lubarda, Celeste Pilegard, Curt Schurgers

Psychology Faculty Articles and Research

Learning is a lifelong process exercised within and beyond the classroom and a vital skill in almost all technical professions. Engineers, in particular, are impacted by rapidly evolving technologies and practices that require continuous learning and adaptation long after their training and the initial transition into their professional careers. However, despite the critical role of learning in their academic success and profession, engineering students experience academically rigorous and challenging courses with very little emphasis or conscious focus on learning strategies that power effective learning. Often-used learning strategies such as rereading, highlighting, repetition, and memorization are intuitive for many students, yet …

Towards Sustainable Manufacturing: A Framework For Resource Conservation And Waste Mitigation, Mahmood Talal Sultan

Thesis/ Dissertation Defenses

The manufacturing industry drives economic expansion, but it also contributes significantly to environmental change and shortages of resources. Therefore, the transformation to sustainable manufacturing has become an urgent need, driven by worldwide efforts to address climate change, minimize waste, and protect valuable assets. This thesis develops a robust framework tailored to the manufacturing sector, focusing on resource conservation and waste reduction. The framework is built on the identification and categorization of Key Performance Indicators (KPIs) and assessment tools, which address five major implementation challenges: complex supply chains, regulatory barriers, economic challenges, technological limitations, and social and cultural challenges.

To build …

Knee-Thigh-Hip Impact In Children: Effects Of Age And Impact Velocity, Mohammad Ziad Turki

Thesis/ Dissertation Defenses

Brief introduction: This thesis examined the crash impact injury outcomes of the knee-thigh-hip complex (KTH) in children based on age and impact velocity using computational modelling. Child occupant (3YO, 6YO, 10YO) Total Human Body Model for Safety (THUMS) models developed by Toyota were used to evaluate the effects of age and impact velocity on pediatric KTH crash impact response. Aims: The main objectives of this thesis are to analyze the effect of child age and impact velocity on KTH crash impact response. Methods: The knee impact simulations were performed based on different impact velocities (1.2, 3.5, 7.2, …

Nanoscale Structure-Property Relationships Of Cyanate Ester As A Function Of Extent Of Cure, Khatereh Kashmari, Josh Kemppainen, Sagar U. Patil, Julieta Barroeta Robles, Pascal Hubert, Gregory Odegard

Michigan Tech Publications

Cyanate esters are key thermosetting resins for composite materials that require structural integrity and resistance to elevated temperatures. Because cyanate ester composites require relatively high processing temperatures, they are susceptible to the formation of process-induced residual stresses, which compromise their overall strength and durability. Process modeling is a key strategy for optimizing processing parameters to minimize such residual stresses. A necessary component of effective and efficient process modeling of composites is computationally established resin property evolution relationships for a range of processing parameters. In this study, the physical, mechanical, and thermal properties of a cyanate ester resin are established as …

How’S It Growing? Tools For Observing Snow And Sea Ice In A Changing Arctic Ocean, Ian Alexander Raphael

Dartmouth College Ph.D Dissertations

September Arctic sea ice extent has diminished by roughly 50% in the 45 years since satellite observations began. The Arctic Ocean may experience ice-free summers within the next decade, with implications for habitat, resource extraction, geopolitics, and local and global climate change. To predict how Arctic sea ice will change in the future, we need to understand its behavior in the present. In situ sea ice mass balance measurements (snow accumulation, ice growth, snow and ice surface melt, and bottom melt) are essential for studying the processes driving rapid changes in the ice pack, and for validating remote sensing measurements …

The Aerodynamics Of Swept, Canted, And Slotted Winglets, Andrew K. Mahler

Mechanical Engineering Master's Theses

Winglets have been used to improve the aerodynamic performance of wings. They do this by decreasing the lift induced drag that is experienced by the wing. The winglet modifies the wingtip vortex generated by adjusting both its size, location and strength. Motivated by previous research on the manipulation of wake vorticity through the use of a forward or backward sweep discovered originally when investigating crescent wings, the presented work investigates the role of sweep, cant and slots on winglets. Sweep was first applied to positive and negative canted wings with a symmetric airfoil, the ONERA M6. The wing flows were …

Thermal Rheological Properties Of Heat-Moisture Modified And Its Application In Multigrain Cookies, Thi Huyen Trang, Li Xianghong, Miao Jinxu, Wang Faxiang, Liu Yongle, Li Shuang

Food and Machinery

［Objective］ To develop low -burden,high -nutrient functional baked foods.［Methods］ A single -factor experimental design is employed,with rapid visco analyzer,rheometer,and differential scanning calorimeter to analyze the physicochemical properties of heat -moisture modified wheat flour.The cookie formula is optimized based on sensory evaluation.［Results］ Heat -moisture treatment significantly enhances the pasting stability and resistant starch content of wheat flour.The optimal auxiliary ingredient formula is 50 g of heat-moisture modified wheat flour,20 g of oat flour,10 g of mung bean flour,and 6 g of resistant dextrin powder.Compared with the control group,the cookies made from the experimental formula show a significantly lower digestibility,with a glycemic …

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 …

Sae Baja Drivetrain Capstone 2024-2025, Leslie Alvarez Cisneros

University Honors Theses

This thesis reviews the 2024-2025 Baja SAE Drivetrain capstone project. The Baja SAE competition mimics real world engineering problems where teams of students design and build off-road vehicles that can handle tough, rough terrain. The objective of this capstone was to design a functional and reliable drivetrain system for the vehicle, within the constraints of a limited budget and the SAE competition guidelines. As part of a 12-member capstone team divided into three subgroups: frame, suspension, and drivetrain. As part of a four person drivetrain team, we picked up where the 2023-2024 team left off by relying on their past …

Human Gut Commensal Alistipes Timonensis Modulates The Host Lipidome And Delivers Anti-Inflammatory Outer Membrane Vesicles To Suppress Colitis In An Il10-Deficient Mouse Model, Ethan Older, Mary K. Mitchell, Andrew Campbell, Xiaoying Lian, Michael Madden, Yuzhen Wang, Lauren E. Van De Wal, Thelma Zaw, Brandon N. Vanderveen, Rodney Tatum, E. Angela Murphy, Yan-Hua Chen, Daping Fang, Melissa Ellermann, Jie Li

Faculty Publications

Correlative studies have linked human gut microbes to specific health conditions. Alistipes is one such microbial genus negatively linked to inflammatory bowel disease (IBD). However, the protective role of Alistipes in IBD is understudied, and the underlying molecular mechanisms remain unknown. In this study, colonization of Il10-deficient mice with Alistipes timonensis DSM 27924 delays colitis development. Colonization does not significantly alter the gut microbiome composition, but instead shifts the host plasma lipidome, increasing phosphatidic acids while decreasing triglycerides. Outer membrane vesicles (OMVs) derived from Alistipes are detected in the plasma of colonized mice, carrying potentially immunomodulatory metabolites into the …

Design And Development Of Hip Implants For Longevity Through Integrating Advanced Groove Structures And Additive Manufacturing, Asarudheen Abdudeen

Thesis/ Dissertation Defenses

This doctoral research concerns the design and optimization of hip implants (HIs) to enhance performance, durability, and improve patient outcomes by addressing the key issues of wear, deformation, and stress distribution. Innovative surface groove designs have been introduced to both a solid and a hollow femoral head with the aim of reducing friction and wear. The addition of grooves, with both a hemispherical and rectangular cross-section, onto the femoral head reduced friction, as debris produced by the inner liner was trapped within the grooves, significantly reducing adhesive wear. A numerical simulation study compared the effects of surface modifications — both …

A Versatile Platform For Designing And Fabricating Multi-Material Perfusable 3d Microvasculatures, Nathaniel Harris, Charles Miller, Min Zou

Mechanical Engineering Faculty Publications and Presentations

Perfusable microvasculature is critical for advancing in vitro tissue models, particularly for neural applications where limited diffusion impairs organoid growth and fails to replicate neurovascular function. This study presents a versatile fabrication platform that integrates mesh-driven design, two-photon lithography (TPL), and modular interfacing to create multi-material, perfusable 3D microvasculatures. Various 2D and 3D capillary paths were test-printed using both polygonal and lattice support strategies. A double-layered capillary scaffold based on the Hilbert curve was used for comparative materials testing. Methods for printing rigid (OrmoComp), moderately stiff hydrogel (polyethylene glycol diacrylate, PEGDA 700), and soft elastomeric (photocurable polydimethylsiloxane, PDMS) materials were …

Bloom Pattern Data, Zhongyuan Wang, Robert J. Lang, Larry L. Howell

ScholarsArchive Data

This data is the supplementary material of the paper "Bloom Patterns: Radially Expansive, Developable, and Flat-Foldable Origami" by Zhongyuan (Kelvin) Wang , Robert J. Lang, and Larry L. Howell.

We present bloom patterns as a family of radially expansive, flat-foldable, and developable origami patterns, many of which are rotationally symmetric. Bloom patterns are defined with a generalized definition and a standardized definition. A classification scheme for bloom patterns is identified, and several types of bloom patterns are analysed. The distinct helical nature that characterizes bloom patterns is described, and a set of compatibility conditions is derived to help determine if …

Effect Of Fibonacci-Inspired Multi-Layer Aluminum Sheets Under Double-Nose Projectile Impact, Shaima Ali Alhosani

Thesis/ Dissertation Defenses

This research examines the ballistic performance of multi-layered Aluminum 2024 sheets designed with Fibonacci-inspired spacing patterns when subjected to double-nose projectile impacts. Through a numerical simulation, five configurations were studied: a monolithic reference plate (L0) with 0.82 mm thickness, and four multi-layer configurations (L1 to L4), all maintaining a constant total thickness of 1.74 mm. Three projectile types were considered Blunt-Conical (BC), Conical-Blunt (CB), and Blunt-Blunt (BB). Among these, the L1 configuration (two layers separated by a 0.1 mm gap) consistently offered the best ballistic resistance, outperforming more complex arrangements. As layer complexity increased from L1 to L4, overall performance …

Derivation And Experimental Validation Of A Parameterized Nonlinear Froude–Krylov Force Model For Heaving-Point-Absorber Wave Energy Converters, Houssein Yassin, Tania Demonte Gonzalez, Gordon Parker, Giorgio Bacelli, Carlos Michelen

Michigan Tech Publications

Wave energy converters (WECs) have gained significant attention as a promising renewable energy source. Optimal control strategies, crucial for maximizing energy extraction, have traditionally relied on linear models based on small motion assumptions. However, recent studies indicate that these models do not adequately capture the complex dynamics of WECs, especially when large motions are introduced to enhance power absorption. The nonlinear Froude–Krylov (FK) forces, particularly in heaving-point-absorbers with varying cross-sectional areas, are acknowledged as key contributors to this discrepancy. While high-fidelity computational models are accurate, they are impractical for real-time control applications due to their complexity. This paper presents a …

Computational And Experimental Study Of Slow Crack Growth In High Density Polyethylene, Abdulla Almomani

Thesis/ Dissertation Defenses

This dissertation investigates the slow crack growth (SCG) behavior of High-Density Polyethylene (HDPE) under various mechanical and environmental conditions. The study combines experimental analysis and computational modeling to enhance the understanding of SCG mechanisms in HDPE, particularly in pressurized pipes and under the exposure to hydrocarbons. A novel Crack Layer (CL) theory-based SCG model is developed and validated through experimental data, offering a predictive framework for HDPE failure assessment. The main objective of this dissertation is to quantify and model the viscoelastic-viscoplastic behavior of HDPE under monotonic and cyclic loading conditions while addressing SCG kinetics in structural applications. The study …

Minimum Ghg Emissions And Energy Consumption Of U.S. Pet And Polyolefin Packaging Supply Chains In A Circular Economy, Utkarsh S. Chaudhari, Abhishek Patil, Tasmin Hossain, David Watkins, Damon S. Hartley, Barbara K. Reck, Robert Handler, Anne T. Johnson, Vicki S. Thompson, David Shonnard

Michigan Tech Publications

There is a wide agreement on the urgency of transforming linear management of plastics towards a circular economy model. However, no clear pathways exist as to required recycling technologies involved and system-wide environmental impacts. This study explores such pathways in the U.S. for the most commonly used packaging plastics through a combination of mechanical and emerging advanced recycling technologies. A system optimization model aimed at minimizing environmental impacts was developed to determine optimal end-of-life (EOL) management and locations of existing and emerging U.S. recycling infrastructures. Our study includes material flows from virgin resin production through semi-manufacturing processes to existing EOL …

Efficient Thermal Design Of Data Centers, Keats M. Baggett, Andrew Ergood, Colin Brace, Jack Zilligen

Mechanical Engineering

Our sponsor needs a way to categorize and quantify the top 3 colocation center sites based on a series of criteria for given power specs. The sponsor also needs a single innovative cooling method to meet thermal and power requirements while also being manufacturable at scale. This device must also be able to interact with the given Colocation Heating Ventilation and Air Conditioning (HVAC) system. This design will be tested to provide insight and data that will be applicable to further the development of colocation center cooling. This project will be executed by the Cal Poly senior project team and …

Aerospace Fastener Installation Tool, Anthony I. Berghout, Matthew K. Eggers, Liam Dunsmore, Jose Pardo

Mechanical Engineering

Contamination, particularly in aerospace manufacturing environments, is a significant concern, especially with fastener designs that incorporate torque-rated breakaway pieces for easier installation. These breakaway pieces are also known as pintails. Howmet has tooling that can collect loose pintails during installation, but they have small capacities and are not ergonomic for aerospace technicians. Their current need is for a light and ergonomic tool capable of installing a wide variety of Ergo-Tech® fasteners while having a large capacity to collect pintails and improve aerospace manufacturing methods. For this Critical Design Stage, we have finalized a design that allows Pintails to pass through …

2-Axis Solar Panel Tracker, Danica Wong, Oliver Barnaal, Anton Orme

Mechanical Engineering

Solar panels generate energy from sunlight. To do this it’s important that they remain pointed at the sun throughout the day. The Cal Poly Micro Grid Lab runs a class that uses a student made solar panel and tracking mount as an instructional tool. This project is beginning to show signs of wear from outdoor use and is unable to run without constant input due to some significant design flaws. The lab needs a new version of the mount to be made that is significantly more reliable and easier to use.

Edwards Lifesciences: Esheath+ Scoring Automation, Tony Lee Avina, Kirth Hirth, Charith Sunku, Humberto Salazar-Banuelos

Mechanical Engineering

Due to a non-disclosure agreement with our sponsor, Edwards Lifesciences, the contents of the report have been omitted.

Kinetic, Wind-Driven Metal Sculpture, Irene Songhee Han, Aiden Brown Largay, Madeline Vang Xiong

Mechanical Engineering

The Interdisciplinary Senior Design Team “Flying Flora” from Cal Poly’s College of Engineering has been tasked with designing and building a wind-driven dynamic metal sculpture for the San Luis Obispo Botanical Garden. The botanical garden wants to fill a large, centrally located vacant space with a kinetic sculpture to attract and welcome visitors. The final design, as approved by the garden’s directors, features a large metal California poppy below a stained-glass and metal butterfly. The flower rotates smoothly in typical wind conditions, drawing the attention of visitors to the sculpture. The butterfly is stationary, positioned at an angle from the …

Aluminum Boat Rotation Fixture, Kevin W. Heiskell, Nathaniel M. Conway, James S. Knowles, Austin J. Kehl

Mechanical Engineering

Aluminum fishing boats are widely used for various water-based activities, including fishing, transportation, and recreation. Their lightweight construction makes them ideal for maneuverability, particularly in regions like Australia. However, the manufacturing process presents challenges, specifically the need to weld both the interior and exterior seams of the hull. As the boat’s weight increases during assembly, flipping it becomes difficult and potentially hazardous. Traditional methods such as cranes or forklifts are inefficient and pose safety risks. To address this, our team developed a rotating fixture that secures the boat at two connection points, one at the bow and one at the …

In-Situ Defect Detection In Selective Laser Melting Using Convolutional Neural Networks, Ethan Gaigalas

Master's Theses

This thesis develops and trains a convolutional neural network (CNN) to classify defects in metal parts produced by selective laser melting (SLM) using acoustic emission (AE) data. The model successfully identified porosity and standard build layers with high accuracy but consistently struggled to classify lack of fusion (LOF) defects, regardless of input type, normalization, or class count. These results suggest that while AE signals contain distinguishable features for certain defect types, LOF signals may be too subtle or inconsistent for reliable detection. The study addresses the ongoing challenge of in-situ quality monitoring in metal additive manufacturing, where defects like cracks, …

Foot Pedal Assistive Device, Julian Rubinstein, Connor Jessen, Isabelle Utsler, Sydney Alexander

Mechanical Engineering

Individuals with lower-limb mobility problems may have trouble accurately locating the pedals of a three-pedal manual transmission car, and some medical conditions cause individuals to fatigue more quickly when driving. This project aimed to create a device that assists in locating the user’s feet, indicates to the user which pedals are currently in use, and provides a visual and physical warning if they are not in the correct place. The project sponsor, Alan Keizer, is the primary stakeholder in this project. This device will be designed specifically for Alan’s Subaru BRZ and will address Alan’s specific lower-limb mobility issues that …

Van Accessibility, Ann Larson, Camelia Anne Noureddine, Stephanie Rose Ruzicka, Kayla Joanne Gowey

Mechanical Engineering

The SLO Achievement House provides resources and activities for their clients, including daily trips to different parts of the community, to keep their clients connected to society. These trips require the clients, many of whom struggle with general mobility and strength, to step up to the high entrance of a van or company car. This daily activity poses a challenge both physically and emotionally for the clients. The current solution utilizes commercially available step stools, which lack handrails, overall stability, and adequate step depth. The Achievement House needs a stool or ramp tailored to their client’s needs and their specific …

7lr-C Upper Limb Dancing Prosthetic, Victor Ochoa, Zoe Kelemen, Ged Mulingtapang, Marley Paltiel

Mechanical Engineering

Ella Wallis, a student at Cal Poly and performer in the Cal Poly Drag Club with a trans humeral upper limb difference, wants a prosthetic device that allows for a large range of motion and high degree of articulation to help them better dance in the style of voguing, allowing them to express themselves further while performing. The prosthetic arm is body-driven and relies on momentum to reposition. It attaches to the user through a harness, which is clipped to a socket with elastic straps to not impede the shoulder’s range of motion. The design contains urethane resin, aluminum, stainless …

Drone Package Delivery System, Aiden Tyler Sim, Ryan Anders O'Toole, Matthew Karl Wyant, James Shaw Glanville

Mechanical Engineering

In response to the demands of the 2025 C-UASC (California Unmanned Aerial Systems Competition), our team developed an autonomous drone payload delivery system capable of two distinct delivery modes: a precision-controlled descent and a high-speed aerial drop. Designed for modular integration with UAV platforms, the system prioritizes reliability, accuracy, and simplicity under desert environmental conditions. Our solution features a custom winch mechanism with a programmable stepper motor, a passive mechanical hook for tension-based release, and a servo-actuated trapdoor for high-altitude drops. The design was extensively tested for structural integrity, motor torque requirements, drop precision, and electronics reliability—culminating in a robust …