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California Polytechnic State University, San Luis Obispo

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Development Of A Novel Bio-Mimetic Ornithopter With Variable Flapping Angle, Geourg Kivijian Jun 2025

Development Of A Novel Bio-Mimetic Ornithopter With Variable Flapping Angle, Geourg Kivijian

Master's Theses

From the beginnings of flight, flapping-winged flight has been a goal of many engineers to mimic and replicate. With gains in aerodynamic efficiency of flight and certain other favorable characteristics such as reduced noise, higher maneuverability, and surveillance opportunities in urban environments, flapping-wing aerial vehicle(FWAV) designs are consistently pursued in many corners of academia and industry. This thesis goes into the development of a flapping wing aerial vehicle with a Bio-mimetic novel drive mechanism that is cable-driven and can produce variable amplitude and frequency flapping stroke. Employing a Field-Oriented Control (FOC) Brushless Direct Current (BLDC) motor, paired with a bio-mimetic …


Design, Fabrication, And Testing Of A Dual-Rate Spring System For Mountain Bike Frames, Lucas P. Grizzle Jun 2025

Design, Fabrication, And Testing Of A Dual-Rate Spring System For Mountain Bike Frames, Lucas P. Grizzle

Master's Theses

The design of full-suspension mountain bikes is a careful balance of suspension kinematics, structural dynamics, and manufacturing optimization for the expected use case. A bike designed to excel in one area will likely exhibit reduced performance in others. This optimization problem is addressed by designing, integrating, and testing a dual-rate spring system within a fully custom frame. The dual-rate spring is fully decoupled from the rest of the suspension kinematics, providing designers with an additional parameter to achieve ideal suspension behavior. This is accomplished by placing a thermoplastic polyurethane (TPU) bushing in series with the rear shock. The influence of …


Statistical Time-History Response Of Mid-Story Isolated Structures In Linearized Elastic Conditions, Min Thit Khant Jun 2025

Statistical Time-History Response Of Mid-Story Isolated Structures In Linearized Elastic Conditions, Min Thit Khant

Master's Theses

This study presents a statistical analysis of the seismic demand of mid-story isolated structures in linearized elastic conditions. The assumed earthquake database consists of 228 ground motions recorded in California from earthquakes with magnitudes greater than 6. A three-degree-of-freedom modeling approach is adopted, and the seismic demands of the substructure, superstructure, and isolation system are determined for varying isolated mass and stiffness ratios. The seismic demand of mid-story isolated structures at the isolation level is expressed in terms of the response of an idealized isolated superstructure supposed to be on the ground, while the demands on the substructure and superstructure …


Model-Based Design Of Compressed Lithium-Metal Pouch Cell Battery Modules For Evtol Applications, Scott J. Stirling Jun 2025

Model-Based Design Of Compressed Lithium-Metal Pouch Cell Battery Modules For Evtol Applications, Scott J. Stirling

Master's Theses

Batteries with higher specific energy and power are essential for extending the range and performance of electric vertical takeoff and landing aircraft (eVTOLs). Anode-free lithium-metal pouch cells offer strong potential at the cell-level but require high compressive pressures to enhance cycle life and discharge performance. These pressures necessitate heavier structural components, reducing packaging efficiency at the module level.

To evaluate this tradeoff, a full-factorial enumeration model was developed to explore viable module designs within a constrained packaging volume. The model scales subsystem masses, enforces design rules and material limits, and accounts for large (~20%) cell thickness changes during cycling.

Results …


The Impact Of Accessibility Features On Player Experience In Video Games, Christine M. Widden Jun 2025

The Impact Of Accessibility Features On Player Experience In Video Games, Christine M. Widden

Master's Theses

While video game accessibility is a growing research topic, few studies investigate how players perceive the presence versus the absence of accessibility features, or how non-disabled players react to the option of accessibility features. This study explores these research gaps, investigating how access to accessibility features affects the experience of both disabled and non-disabled players. For the purposes of this study, a small platformer game was developed with as many accessibility features as feasible for the scope of the project. An A vs.\ B study was conducted in the game, with anonymous participants randomly assigned to version A, with all …


Development Of A Reaction Wheel System For Cal Poly’S Spacecraft Attitude Dynamics Simulator, Caleb Nalley Jun 2025

Development Of A Reaction Wheel System For Cal Poly’S Spacecraft Attitude Dynamics Simulator, Caleb Nalley

Master's Theses

The Cal Poly Spacecraft Attitude Dynamics Simulator (SADS) is an ongoing project to develop a system capable of simulating the attitude dynamics and kinematics of a rigid body in space. Actuations on the SADS are performed by reaction wheels, however the current reaction wheels have various issues that decrease system performance and are not independent of the SADS. The reaction wheel developed as part of this thesis will be designed to improve performance and set out design specifications tailored to the SADS, serve as an independent assembly that can be transferred to other systems, and provide a general outline for …


Study On The Application Of Smart Electric Meters For Secondary Voltage Protection, Jayaditya Sisodia Jun 2025

Study On The Application Of Smart Electric Meters For Secondary Voltage Protection, Jayaditya Sisodia

Master's Theses

The purpose of our research is to utilize PG&E’s Smart Meters installed across California to protect the Secondary Voltage delivered to the meter. This means detecting electrical faults between the utility’s distribution transformer and the installed Smart Meter. Our goal is to propose and implement various solutions through additional devices and protocols to detect and prevent these faults, communicate them with the meter, and forward fault information to the utility. A device will be designed to be installed on the transformer, detect faults, shut off power transmission, and communicate to the meter via fiber optic cable. Research will then be …


Open Source Asic Design Curriculum, Francisco Wilken Jun 2025

Open Source Asic Design Curriculum, Francisco Wilken

Master's Theses

The ever-growing importance of Application-Specific Integrated Circuits (ASICs) in a high-compute world necessitates that college graduates entering the workforce are well prepared to design them. This thesis details the design of novel ASIC curriculum, using open source tools to teach at the undergraduate level. By moving to a higher level of abstraction than classical transistor-focused coursework, chip design material can be made accessible earlier in an undergraduate degree. Additionally, open source tools provide a powerful, free, and portable platform for students to create their own designs, solving assignments focused on industry readiness. Finally, this thesis studies the results and challenges …


Modeling And Efficiency Analysis Of Hybrid Ac/Dc And Conventional Ac House Electrical Systems For Net-Zero Energy Homes, Tyler Bury Jun 2025

Modeling And Efficiency Analysis Of Hybrid Ac/Dc And Conventional Ac House Electrical Systems For Net-Zero Energy Homes, Tyler Bury

Master's Theses

This thesis presents the design, simulation, and comparative efficiency analysis of hybrid AC/DC residential homes versus conventional AC homes for Net Zero Energy Homes (NZEH). Motivated by the increasing prevalence of DC-native technologies such as solar photovoltaics, battery storage, and DC-powered electronics, this work evaluates whether hybrid AC/DC distribution can offer measurable efficiency benefits over traditional systems. Twelve detailed house models were developed—six employing a hybrid AC/DC architecture and six based on conventional AC systems, each supplying a combination of AC and DC residential loads. Simulations were conducted using MATLAB/Simulink to model steady-state efficiency under various loading conditions. Grid configurations …


Thermally Perfect Augmentation Of A Supersonic Inlet Design Tool That Uses Method Of Characteristics, Mario V. Guardado Jun 2025

Thermally Perfect Augmentation Of A Supersonic Inlet Design Tool That Uses Method Of Characteristics, Mario V. Guardado

Master's Theses

This work is the first in a series to augment a supersonic air inlet design tool based in Python 3 to incorporate new models that increase the range of applicability of the tool. This effort focuses on improving the thermodynamics model by incorporating a thermally perfect gas model. This tool utilizes method of characteristics to solve the governing equations for an inviscid, irrotational, isentropic, steady, supersonic flow field. Multiple test cases are used to assess the accuracy of all new models. A comparison is made between the original code’s test case for a supersonic inlet at low temperatures to verify …


Reverse Engineering Bring Up And Profiling Of Multi-Fpga Systems, Henry A. Evans Jun 2025

Reverse Engineering Bring Up And Profiling Of Multi-Fpga Systems, Henry A. Evans

Master's Theses

FPGAs have long been used for prototyping and verifying high-speed digital designs in industry and in academic research. As ASIC designs have grown in complexity and size, prototyping those designs on FPGAs has required multiple FPGAs that sometimes span multiple servers. Western Digital donated multiple FPGA-based systems to Cal Poly in 2023. These servers contain multiple high-end AMD FPGAs that are ideal for prototyping large high-speed digital designs, however the full documentation on how to use the servers and how the servers work was not provided. The servers did not come with any information on how to program the FPGAs, …


Griddle: A Novel Hardware Based Matrix Multiplier Architecture, Seth Kiefer Jun 2025

Griddle: A Novel Hardware Based Matrix Multiplier Architecture, Seth Kiefer

Master's Theses

Matrix multiplication is a computational cornerstone in modern artificial intelligence and scientific computing, yet general-purpose processors struggle to perform these operations efficiently at scale. This thesis presents Griddle, a novel hardware architecture for matrix multiplication implemented on a Xilinx Artix-7 FPGA. Griddle focuses on flexibility and scalability by adopting a purely iterative approach that supports arbitrarily shaped input matrices without requiring padding or strict dimensional constraints. The architecture uses computational pipelines to execute a multiplication operation. Each pipe consists of a multiplication core and accumulation buffer that compute matrix products in parallel. The multiplication core contains a set of multiplier …


Streamlined Intelligence: Resource-Efficient Machine Learning For 5g Nr V2v Channel Equalization, Jacqueline G. Radding Jun 2025

Streamlined Intelligence: Resource-Efficient Machine Learning For 5g Nr V2v Channel Equalization, Jacqueline G. Radding

Master's Theses

As autonomous vehicles continue to evolve, reliable and efficient real-time communication between vehicles is essential for safety and performance. This thesis explores Streamlined Intelligence: Resource Efficient machine learning for 5G NR V2V Channel Equalization, focusing on lightweight random forest decision tree models to address the challenges of channel equalization in 5G New Radio (NR) vehicle to vehicle (V2V) systems. Using orthogonal frequency division multiplexing (OFDM) with QPSK modulation, the study simulates data transmission in nonlinear channels characterized by obstructions, Doppler shifts, and fading. Decision trees are proposed as a computationally efficient alternative to other machine learning methods while being compared …


"Great Big Beautiful Tomorrow": Disneyland, Science, And The Cultural Cold War, Emily Searson Jun 2025

"Great Big Beautiful Tomorrow": Disneyland, Science, And The Cultural Cold War, Emily Searson

Master's Theses

Disneyland, the popular Anaheim-based theme park in California, opened its doors during heightened Cold War tensions in 1955. In this thesis, I trace the origins of Tomorrowland, one of the five original themed lands in Disneyland that included futuristic rides and attractions to depict Walt Disney’s imagining of the year 1986. I examine Tomorrowland in particular to argue that WED Enterprises (Disneyland, Inc.’s research and development arm) and Disney’s vision of scientific progress aligned with U.S. Cold War policy goals, especially containment. Disney and WED Enterprises meticulously planned Tomorrowland with the help of notable American defense contractors, including the Monsanto …


Experimental Characterization And Finite Element Analysis Of The Effects Of Pitting Corrosion On The Mechanical Properties Of Stainless Steel, Duncan Jay Fure, Long Wang Jun 2025

Experimental Characterization And Finite Element Analysis Of The Effects Of Pitting Corrosion On The Mechanical Properties Of Stainless Steel, Duncan Jay Fure, Long Wang

Master's Theses

Many structures do not fail from poor design, but instead from environmental degradation. Corrosion is one mode whose effects can be diminished, but not eliminated, by employing corrosion resistant materials, such as 304 stainless steel, which are still subject to pitting corrosion. Pitting corrosion is a chemical process of the localized removal of material leaving cavities. Despite the prevalence of pitting corrosion, there has been limited testing conducted of the effect of stress during corrosion. This study conducted accelerated controlled corrosion experiments with and without mechanical loading and various corrosion times. Pit morphology of different conditions was analyzed with statistical …


Low Earth Orbit Drag Sail Degradation Due To Atomic Oxygen And Ultraviolet Radiation, Hannah Rost Jun 2025

Low Earth Orbit Drag Sail Degradation Due To Atomic Oxygen And Ultraviolet Radiation, Hannah Rost

Master's Theses

As the orbital debris population increases, so does the risk of collisions with operational spacecraft. In response, the Federal Communications Commission has shortened the deorbit requirement from 25 years to five years. While natural atmospheric decay was sufficient under the previous guideline, many objects with low area to mass ratios can no longer passively comply. Smaller, non-propellant-carrying space objects such as CubeSats lack the ability to maneuver and must rely on alternative deorbit methods. One proposed solution is to deploy a drag sail at end of life to increase atmospheric drag and accelerate orbital decay. However, exposure to atomic oxygen …


In-Situ Defect Detection In Selective Laser Melting Using Convolutional Neural Networks, Ethan Gaigalas Jun 2025

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, …


Analysis And Design Of A Building With Inter-Story Seismic Isolation, Sofia Barale Jun 2025

Analysis And Design Of A Building With Inter-Story Seismic Isolation, Sofia Barale

Master's Theses

Earthquakes can cause considerable damage to buildings, and their unpredictability means engineers must often design for worst-case scenarios. The current goal of building design codes is to prevent collapse and loss of life during a seismic event. However, after a seismic event, even if the building did not collapse, enough damage can leave the building uninhabitable and need of extensive and costly repairs. Therefore, seismic mitigation techniques like base isolation systems have been widely implemented as a seismic design solution. An isolation system works to decouple the structure from the ground and laterally displaces it with a longer fundamental period …


Design And Development Of A Half-Bridge Llc Resonant Converter Laboratory Module, Alyssa Lam Jun 2025

Design And Development Of A Half-Bridge Llc Resonant Converter Laboratory Module, Alyssa Lam

Master's Theses

Resonant DC-DC converters have become a well-known solution in power supplies due to their ability to improve efficiency by utilizing soft-switching techniques. This further has caused a growing interest in industry to use these converters for high-switching-frequency, high-efficiency, and high-power applications such as EV charging stations, photovoltaic systems, battery chargers, etc. One particular resonant topology that has gained popularity in recent years is the LLC resonant converter. Due to the prevalent use of the LLC resonant converter, it is therefore crucial for students preparing for a career path in power electronics to become well-versed in the concept and implementation of …


Tuned Liquid Damper Design Using Liquid Sloshing In A Horizontal Cylindrical Tank, Vedant M. Patel Jun 2025

Tuned Liquid Damper Design Using Liquid Sloshing In A Horizontal Cylindrical Tank, Vedant M. Patel

Master's Theses

Vibration isolation is an essential design requirement for several real word applications including industrial machinery, automobiles and building structures. Different techniques of vibration isolation are employed in each of these applications. One such vibration isolator used in tall buildings is known as the Tuned Mass Damper , where a mechanical mass (pendulum, bogey, cylinder) is located at the top portion of the building and is connected to the building through a suspension. This mechanical mass – suspension system is designed to oscillate out of phase with the building in order to dissipate the vibration. Several buildings such as, Taipei 101, …


Coherent Synchronization For Distributed Digital Phased Arrays, Zachary C. Numa Jun 2025

Coherent Synchronization For Distributed Digital Phased Arrays, Zachary C. Numa

Master's Theses

Distributed digital phased arrays are rising technologies that help enable applications such as search and rescue operations, wireless communication, radar navigation, and military operations, among many others. Due to their improved angular resolution, digital phased arrays offer superior direction-finding capabilities compared to traditional analog phased array systems. However, this improvement comes at the cost of increased complexity—specifically, the need for precise synchronization of phase, time, and frequency across physically separated nodes. Without synchronization, the distributed phased array's gain and direction-of-arrival (DoA) estimations deteriorate significantly.

There are multiple aspects to implementing and synchronizing a non-stationary distributed digital phased array. This research …


A Decision Support System For Conference Session Selection Using Natural Language Processing, Tillman E. Erb Jun 2025

A Decision Support System For Conference Session Selection Using Natural Language Processing, Tillman E. Erb

Master's Theses

Conference attendees are faced with selecting from hundreds to thousands of presentations and sessions in pursuit of new findings and methods relevant to their area of interest, an overwhelming amount of information from which to clearly make a decision. To address this, we developed a decision support system leveraging natural language processing (NLP) techniques such as semantic matching. By creating and matching embeddings of conference presentation abstracts and titles, the application provides improved query matching compared to keyword searching. We introduce Session Scout, a novel conference decision support system built upon a semantic retrieval framework. Session Scout is designed to …


Open Source Microgrid Integration, Zachary J. Kwast Jun 2025

Open Source Microgrid Integration, Zachary J. Kwast

Master's Theses

Microgrids are small-scale electrical systems that operate in tandem with a centralized grid to provide power to a smaller group of target devices. These microgrids are used for a wide range of different purposes, which invites the need for a generalized model that can be tweaked for a variety of uses. This document goes over the theory used to design an open source AC and DC microgrid meant for use by anyone. The microgrid is created using a Raspberry Pi that controls two different power converters so that a wide range of voltage and current characteristics can be achieved. These …


Investigation Into Silicone-Silicate Conversion Due To Atomic Oxygen In The Low Earth Orbit Environment, Justin T. Self Jun 2025

Investigation Into Silicone-Silicate Conversion Due To Atomic Oxygen In The Low Earth Orbit Environment, Justin T. Self

Master's Theses

Silicones have been widely used over the years in spacecraft for a variety of functions, but atomic oxygen (AO) exposure in Low Earth Orbit causes a silicate (SiO2) surface layer to rapidly develop on the silicone which results in a permanent change in its thermal and optical properties. Although this silicone to silicate conversion is known to occur, statistical predictions of layer formation as a function of time on orbit are not found in literature. This thesis utilized optical and scanning electron microscopy, Fourier-Transform Infrared Spectroscopy, diffuse reflectance spectroscopy, and nonlinear regression statistical techniques after RF plasma asher …


Density-Based And Model-Based Clustering With Tidyclust In R, Brendan S. Callender Jun 2025

Density-Based And Model-Based Clustering With Tidyclust In R, Brendan S. Callender

Master's Theses

Clustering is a fundamental technique in unsupervised learning that can be used to find hidden patterns and structures within unlabeled data. The tidyclust package in R provides a unified interface for applying various clustering techniques to data. This paper outlines the addition of density-based clustering with DBSCAN, and model-based clustering using Gaussian mixture models (GMMs) to the tidyclust package. DBSCAN can be performed using the db_clust() function and makes use of the dbscan package implementation as its engine. GMMs can be fit using the gm_clust() function which makes use of the mclust package implementation. This paper highlights the changes made …


Atomic Oxygen Considerations For Low Earth Orbit Spacecraft, Hannah Rost, Justin Self Jun 2025

Atomic Oxygen Considerations For Low Earth Orbit Spacecraft, Hannah Rost, Justin Self

Baker/Koob Endowments Awarded Projects

In Low Earth Orbit (LEO), spacecraft are exposed to a harsh environment which includes atomic oxygen (AO) and vacuum ultraviolet radiation (VUV). AO interaction with spacecraft materials results in erosion, structural, and optical property degradation. This damage is often accelerated during concurrent vacuum ultraviolet (VUV) radiation exposure. This study utilized laboratory equipment in the Cal Poly aerospace and materials engineering departments to characterize changes in material properties after AO and VUV radiation exposure. This proposal requested funds for a replacement bulb that will allow for two separate but related studies that investigate synergistic effects of AO and VUV on spacecraft …


Emergency Bleeding Education Fixture, Nate Colley, Kennedy K. Austin Jun 2025

Emergency Bleeding Education Fixture, Nate Colley, Kennedy K. Austin

Biomedical Engineering: Graduate Reports and Projects

Despite the deadly nature and widespread occurrence of emergency bleeding events, there are currently no training devices or demonstrations which educate users on the urgency of these events and potential methods to address them. Additionally, current models often fail to replicate physiological conditions correctly. A fixture was created to demonstrate the urgency of hemorrhaging events and educate users on potential methods for treating hemorrhaging, namely tourniquets and pressure wraps. This fixture utilized gravity to replicate systolic blood pressure, a silicone model to replicate various adult leg sizes and correct tissue properties, and a tubing system with varying compliance to replicate …


Underground Lrt Station, Revital Mesika Jun 2025

Underground Lrt Station, Revital Mesika

Fire Protection Engineering: Culminating Experience Project Reports

This report presents a comprehensive fire safety and evacuation systems analysis for the underground light rail terminal station project. The station features two main levels— concourse and platform—and is strategically located adjacent to a sports stadium.

Station Overview: The underground light rail terminal station is a two-level facility strategically positioned adjacent to a major sports stadium. The station operates as a critical transportation hub with distinct functional zones designed for efficient passenger flow and emergency evacuation:

Concourse Level (3.5 meters below ground): Functions as the primary passenger processing and circulation hub. This level serves as the main entry control point …


Genesis Station Fire Protection And Life Safety Analysis, Mark Anthony Bautista Jun 2025

Genesis Station Fire Protection And Life Safety Analysis, Mark Anthony Bautista

Fire Protection Engineering: Culminating Experience Project Reports

This fire protection and life safety analysis evaluates GENESIS Station, a nine-story Type I-B mixed-tenant building located in Daly City, California. The facility includes business, research laboratory, and assembly occupancies. A combination of prescriptive code compliance and performance-based analysis was applied to assess the building’s overall fire safety strategy.

The building utilizes a layered fire protection strategy that combines passive fire resistive construction with active systems. Fire rated construction separate tenant suites, limiting the spread of fire and smoke, defining hazardous materials control areas, and ensuring compliant separation of egress paths.

Active fire protection systems include a fully automatic sprinkler …


Srs Training Facility, Brandon Romero Jun 2025

Srs Training Facility, Brandon Romero

Fire Protection Engineering: Culminating Experience Project Reports

This report presents a comprehensive fire protection and life safety analysis of the Savannah River Site (SRS) Training Center. A detailed prescriptive code analysis confirmed the building's compliance with applicable standards regarding construction features, occupancy classification, and fire-rated assemblies. Fire resistance provisions are met, with key areas such as exits, stairwells, and the records storage room. The building’s layout, height, number of stories, and floor area also comply with the allowable limits established by the IBC. Fire protection systems include a proprietary fire alarm system with voice notification, extensive smoke and heat detection coverage, and a wet-pipe sprinkler system designed …