Engineering Commons^™

The Effects Of Carbon-Fiber Plates And Peba-Based Midsole Foam In Running Shoes On Lower-Limb Joint Kinetics And Kinematics In Recreational Female Runners, Jordan M. Allen

Master's Theses

The recent increase in long-distance running participation and the rapid advancement in footwear technology have created a need for research on injury prevention in this growing population of recreational runners. When “super shoes” were first introduced to the running scene, they caught the attention of runners worldwide with the rapid improvement in marathon performance [1]. Today, every major running brand offers its own version of a super shoe, each incorporating a carbon-fiber plate and PEBA-based midsole foam. While previous studies have shown the performance benefits of these shoes, a gap remains in the literature regarding how they impact knee, hip, …

Simulation Of Powder Spreading For Metal Additive Manufacturing, Florence Duff

Master's Theses

The powder recoating process for Laser Powder Bed Fusion requires iterative experimentation to develop the correct process parameters that will result in high quality parts. There currently lacks good spread quality metrics and models for optimizing spread quality. A machine that simulates the powder spreading process was built to streamline the process of selecting process parameters for specific types of powders without having to operate the full laser system. The parameters investigated were the layer thickness and spreading speed. The response variables were metrics developed to assess spread quality: the percentage of the build plate covered by powder and the …

Evaluating Design Choices For Gpu-Accelerated Finite-Difference Time-Domain Simulation On Resource-Constrained Devices, Joel Manesh

Master's Theses

The Finite-Difference Time-Domain (FDTD) method is a numerical technique for solving partial differential equations. It was first developed to solve Maxwell’s equations for electromagnetic wave propagation and has since been extended to model other physical phenomena governed by wave propagation. Because the FDTD method is data-parallel, it is well-suited for GPU acceleration; modern FDTD-based simulations run offline on large GPU clusters. There is, however, very little research on running FDTD on resource-constrained embedded GPUs, which are increasingly popular for real-time applications.

This thesis explores a CUDA-based FDTD solver for the 3D wave equation on the Nvidia Jetson Orin Nano. This …

Evaluation Of Laser Doppler Flowmetry And Transillumination Laser Speckle Contrast Imaging To Measure Blood Flow Change In Ischemia Mouse Hindlimb Models, Simon Park

Master's Theses

Peripheral Artery Disease (PAD), caused by plaque buildup and narrowing of the arteries, reduces blood flow to the extremities. Promoting collateral arteriogenesis can help redirect blood flow. However, simple growth of collaterals may not be enough to reverse PAD. Instead, the ability for the collaterals to vasodilate and control blood flow is important, meaning assessing collateral function is important for the arteriogenesis assesment. Although microscopy techniques can measure vasodilation, contrast limitations in larger vessels such as collaterals make blood flow measurements difficult. Techniques such as ultrasound or magnetic resonance imaging (MRI) can measure blood flow but have limitations with cost …

Computational Modeling To Evaluate Bipolar Flexible Electrode Designs For Use In Sciatic Nerve Stimulation, Krystyna S. Allman

Master's Theses

Peripheral nerve stimulation is clinically used to manage pain, rehabilitate motor function, and promote nerve regeneration. The sciatic nerve is often studied for stimulation due to its accessibility and clinical relevance. A conventional nerve cuff electrode is the least invasive method for nerve stimulation, but the mismatch of mechanical properties of the electrode with the nerve tissue can cause damage to the nerve and the electrode itself. This study investigated a novel bipolar, gold nanowire-based cuff electrode design and its ability to selectively activate fibers in the rat sciatic nerve at varying interelectrode spacings. In COMSOL, A finite element model …

Development And Verification Of An Updated Thermal Model For Cal Poly's Small Thermal Vacuum Chamber, Bryce G. Leonard

Master's Theses

This thesis discusses modifications made to the Small Thermal Vacuum (TVAC) Chamber in the Space Environments Laboratory at California Polytechnic State University, San Luis Obispo, and the development and verification of an updated thermal model reflecting these changes. The chamber was redesigned to improve thermal performance, featuring a homogeneous aluminum platen coated with Aeroglaze Z306 to enhance radiative heat transfer, along with expanded data acquisition capabilities for temperature and pressure measurements.

A new thermal model of the chamber was developed in SolidWorks using a finite element approach. The model incorporates conductive and radiative heat transfer mechanisms and is configured to …

Lora Networking Hardware Reference Designs For Terrestrial And Low-Earth-Orbit Communications, Kevin Nottberg

Master's Theses

The work presented here demonstrates a highly robust and tested LoRa networking hardware reference design to meet the needs of the embedded networking company OWL Integrations. The hardware presented integrated a unique combination of features and design choices. The detailing of its unique design is potentially of use to others for use in fielded battery powered terrestrial sensor networking hardware utilizing LoRa. Also, the terrestrial hardware presented is shown to have the capability to support command and control (C2) LoRa links in low-earth orbit beyond terrestrial systems. The design presented has a more U.S. centric component bill-of-materials (BOM), with the …

Analysis And Design Of Auger Cast Piles With Isolation Casing, Zachary Lindsay

Master's Theses

This research addresses the analysis and design of double cased piles. Bay Area Rapid Transit (BART) runs a large rail system both above and below ground that connects the entire Bay Area. BART requires that all new constructions avoid transmitting axial load to their tunnels from adjacent piles. If piles fall within the zone of influence, builders must install double cased piles. Double casing is where there is an extra casing around the pile, with an air gap between them. The air gap prevents load from transferring to the outer casing. The length of this casing is called the isolation …

Short Arc Angles-Only Initial Orbit Determination For Reliable Reacquisition Of Low Earth Orbit Objects, Isabella Rackemann

Master's Theses

Low Earth orbit (LEO) is becoming increasingly congested, furthering the need for accurate tracking and catalog maintenance. Initial orbit determination (IOD) is the first step in this process, providing a preliminary estimate of an object’s state given observations. When it comes to LEO optical observations, a large portion of them are inherently short in duration. Angles-only IOD methods struggle with this data, often producing highly inaccurate solutions that limit reacquisition capabilities. This study expands on prior short arc IOD research, testing seven classical and assumed circular orbit (ACO)-modified angles-only IOD algorithms on real LEO observational data spanning 0-4 degrees of …

Design And Parametric Study Of A Mems-Based Reservoir Computer For Reinforcement Learning, Andrew P. Carr

Master's Theses

Single-node reservoir computing (RC) is a hardware-efficient approach to machine learning, leveraging the dynamics of physical systems. In this work, two reinforcement learning algorithms, Q-learning and Proximal Policy Optimization (PPO), are applied to a simulated micro-electro-mechanical system (MEMS)-based reservoir computer to solve both discrete and continuous control tasks. MEMS-based reservoirs are low-power, compact, and their natural frequencies (kHz to MHz) pair well with real-time control loops. To explore the relationship between reservoir dynamics and learning performance, a parametric study is conducted on two reservoir hyperparameters, reservoir size and neuron separation, using CartPole-v1 and MountainCar-v0. The RC successfully learns multiple tasks …

Design For Repairability: Analyzing The Evolution Of Smartphone Repairability To Generate Design Insights, Pranav Peddinti

Master's Theses

Smartphones are a major part of daily life, allowing people to communicate, browse the internet, shop, and enjoy entertainment. However, smartphones tend to be replaced quickly and therefore contribute to the growing electronic waste problem. The lifecycle of a smartphone can be extended by designing them to be more repairable, making it easier for owners and users to perform the repairs themselves. By only replacing failing components, the device can be in use longer, reducing the waste and pollution generated by replacing the device entirely. Therefore, product designers and engineers must focus on designing smartphones to be more repairable. Design-for-repairability …

Alford Loop Antennas For Ultra-High Energy Neutrino Detection, John K. Kimura

Master's Theses

The neutrino is a fundamental particle of matter emitted by high energy phenomena, such as supernovae and black holes. Detecting neutrinos can give scientists information regarding the frequency of high-energy cosmic events, as well as point them towards specific high-energy events. Ultra-high energy (UHE) neutrino interactions in Greenland ice result in electromagnetic pulses between 200MHz and 800MHz. The Radio Neutrino Observatory - Greenland (RNO-G) seeks to observe the resultant electromagnetic waves. The Alford Loop antenna is proposed to detect these emissions, because of its dipole-like radiation pattern, horizontal polarization, and adequate dimensions to fit in a 10" diameter ice borehole. …

Thermally Induced Color Changes In Iron Oxide Pigments Used In Architectural Coatings, Han Diep

Master's Theses

The 2025 Palisades Fire was one of the most destructive wildfires in the history of Los Angeles, destroying thousands of structures and severely impacting the communities after. This widespread destruction demonstrated an urgent need for more effective wildfire prevention strategies. Architectural coatings do not only provide aesthetics and protection against environmental conditions but can also function as a thermal indicator when a fire breaks out. This study examines the thermally induced color transformation of iron oxide pigments, commonly used in earthtone paint, to provide information relevant to CAL FIRE for improved analysis of wildland-urban interface (WUI) fire behavior and mitigation …

Dot Product Engine Based Neuromorphic Hardware For Continuous-Time Biomedical Signal Classification, Sanjeev Srinivasan

Master's Theses

Accurate diagnosis of pathological conditions from biomedical signals, such as electrocardiograms (ECGs) is often performed offline, making it time-consuming, costly, and inefficient, especially when abnormal patterns are rare and long-term monitoring generates large amounts of data. To address this, this work proposes a compact, scalable, and programmable neuromorphic system designed for real-time preliminary arrhythmia detection and classification using ECG signals, that can be extended to other biomedical signals. The proposed design processes ECG signals using a delta modulation-based spike encoder, followed by classification with a dot-product engine (DPE) based spiking neural network (SNN) processor and winner-take-all (WTA) circuit. The architecture …

Development Of A Multi-Mode Switching-Inverter Laboratory Module For An Introductory Power Electronics Course, Darcy Eliasi

Master's Theses

DC–AC converters, or inverters, are essential power‑electronic interfaces widely used in photovoltaic systems, microgrids, energy‑storage installations, and numerous other modern electrical applications. This thesis presents the design, construction, and testing of an improved laboratory module developed as a student learning tool for demonstrating four fundamental inverter switching techniques: simple square wave (SSWI), modified square wave (MSWI), bipolar PWM, and unipolar PWM. Building upon the previous module, the improved design centers on three key enhancements. These include the selection of a more suitable wave‑generation solution, a multiplexer‑based mode‑selection architecture that reduces user complexity and eliminates conflicting signal configurations, and the integration …

Optimization Of Repeat Ground Track Constellation Design For Complex Discontinuous Regional Coverage, Paige Jewell

Master's Theses

The continued growth of low Earth orbit (LEO) satellite constellations motivates efficient constellation design methods to reduce cost and complexity. Although brute-force methods are commonly employed in the preliminary design of satellite constellations, pairing analytic methods with optimization algorithms provides a more efficient means of searching the design space. Constellation design for continuous global and regional coverage is well-established; however, strategies for discontinuous regional coverage remain underdeveloped. This thesis focuses on an analytic geometry-based method for computing satellite coverage and revisit metrics, coupled with genetic algorithm optimization to efficiently explore the design space. The viability of this method is shown …

Contribution Of Slotted Web To The Cyclic Behavior Of Bare And Composite Beam-To-Hss Column Connections, Pablo Ulargui Ramos

Master's Theses

Slotted web connections produce consistent and meaningful improvements in the cyclic behavior of bare and composite beam-to-HSS column connections. Across the eight connections investigated in this thesis, the introduction of a slotted web increased rotational capacity by approximately 7% to 37% and increased cumulative energy dissipation at the strength-degradation limit by approximately 37% to 81%. These improvements were accompanied by only a small reduction in ultimate flexural resistance on the order of 3% to 8%, attributable to the loss of web cross-section at the slot and, for the more flexible H/t = 16 columns, to increased out-of-plane deformation of the …

Effects Of Atomic Oxygen Exposure On Stressed Drag Sail Materials For Low Earth Orbit Applications, Nazanin Sadeghian Dezaki

Master's Theses

As low Earth orbit (LEO) has become an increasingly valuable region for satellite operations, it has grown increasingly congested. The Federal Communications Commission (FCC) deorbit regulations require satellites to be deorbited within 5 years of launch, and drag sails represent a practical means of meeting this requirement. An important consideration for drag sail design is the effect of atomic oxygen (AO) on sail materials. To address the gap in the literature regarding the behavior of stressed drag sail materials under AO exposure, a new test plate was manufactured for the California Polytechnic State University minimum atmospheric experimentation (MAX) AO chamber. …

A Higher Order Panel Method With Vortex Particle Wake, Luca Flick-Kaiser

Master's Theses

Panel codes were some of the earliest methods for computing the flow around aircraft. Despite the availability of higher fidelity CFD methods, panel methods remain an essential tool for the development of modern aircraft, allowing engineers to quickly iterate during the conceptual design phase.

This work develops and implements a high order panel method using Python. The wake is modeled using vortex particles, resulting in an accurate wake representation with minimal user input. The integration of the higher order singularity distributions has been extended to include the calculation of the velocity gradients necessary for the vortex particle implementation. The use …

Practical Multimodal Wearable Sensing For Functional Upper Extremity Primitive Classification With Application To Stroke Rehabilitation, Nicholas Weiss

Master's Theses

Stroke often causes long-term weakness and impaired motor control in the upper extremity (UE), making everyday tasks such as reaching, grasping, and moving objects more difficult. Restoring functional arm use is therefore a central goal of post-stroke rehabilitation. Measuring affected arm use continuously and objectively is important because isolated clinical assessments may not fully capture how the affected arm is used during therapy or daily life. Wearable sensors offer a promising approach for monitoring, but raw sensor signals are difficult to interpret directly. Functional movement primitives address this issue by describing UE behavior as smaller, task-agnostic movement units.

This thesis …

Development Of A Free-Floating Space Robotic Simulator, Truman: Terrestrial Robotic Unit For Multibody Analysis And Navigation, Jackson W. Cordova

Master's Theses

This work describes the development of a 3 Degree-of-Freedom (DOF) robotic manipulator for use on a free-floating planar air-bearing vehicle. The system developed aims to serve as a foundation for future space robotics research at the California Polytechnic State University (Cal Poly)’s Space Robotics Laboratory. Systems doc- umentation describes conceptual operation and architecture of the proposed system: Terrestrial Robotic Unit for Multibody Analysis and Navigation (TRUMAN). The key operation of TRUMAN is to study a self launch maneuver of a free-floating ve- hicle including 4 distinct phases: launch off a fixed rail, coast, reorientation using manipulator motion, and capture of …

Design And Development Of A Resonance Ignition System Using Gaseous Propellants, Benjamin J. Hoefer

Master's Theses

This work presents the development and experimental evaluation of a resonance igniter (RI) operating with premixed gaseous propellants. Resonance ignition is a non-electrical ignition concept in which an underexpanded jet impinges on a closed-end Hartmann–Sprenger tube (HST), generating cyclic compression and expansion waves that rapidly heat gas near the tube endwall. A modular experimental system was designed and built to investigate resonance ignition using methane–air and methane–oxygen mixtures. The system includes a supplemental configuration that may probe for mixture conditions favorable to ignition, informing RI testing. Pressure and temperature measurements were used to characterize pressure control, mixture pressure ratio (MPR), …

Analysis And Design Of A 2-Bit Millimeter-Wave Reconfigurable Intelligent Surface And Investigation Of Fss-Assisted Angular Stability, Max Spalek

Master's Theses

Millimeter-Wave (mm-wave) technology utilizes high frequency spectrum and can deliver multi-gigabit speeds, ultra-low latency, and massive bandwidth capacity. However, this technology is rather new and many technical challenges remain. On the other hand, Reconfigurable Intelligent Surfaces (RIS) have emerged as promising structures for controllable electromagnetic wavefront manipulation in wireless communication systems. This thesis presents the design of a 2-bit RIS unit-cell element operating throughout the 30–34 GHz mm-wave band, where the structure was progressively refined from an initial resonating geometry toward a grounded reflective RIS configuration. The proposed structure utilizes PIN-diode switching states to produce four discrete reflected phase states …

Development Of A Video-Based Tool To Measure Motor Asymmetry In Infants At Risk For Hemiparesis, Roha Ali

Master's Theses

Congenital hemiparesis is a unilateral motor impairment stemming from brain injury in utero or early postnatally. Hemiparesis can be difficult to detect in early infancy with current clinical tools. Yet, early identification of motor asymmetry could play a key role in the design of effective early intervention and rehabilitation strategies. This thesis presents the development and validation of a video-based tool designed to extract infant limb movement data using DeepLabCut’s (DLC) machine learning network. The pipeline was developed using videos of typically developing (TD) infants and infants with Asymmetric Perinatal Brain Injury (APBI), all at or under 3 months corrected …

A Security Framework For Pacemaker Lead Failure: Anomaly Detection System And Failsafe Policy Considerations, Ethan Wagner

Master's Theses

Embedded system security in implantable medical devices (IMDs) remains an underexplored challenge due to the unique constraints of these systems. Specifically, pacemakers are optimized for ultra-low power consumption to maximize device lifespan, are highly resource constrained, and demand reliable and correct operation to prevent severe health consequences. These systems rely on sensing electrodes, called leads, to detect cardiac activity and stimulate the patient’s heart when appropriate. Therefore, pacemaker lead integrity is a critical issue, as malfunction or compromise can result in device failure jeopardizing patient safety.

The security framework presented in this thesis integrates several works to proactively detect and …

Large Scale Kmer-Based Proteomic Analysis: An Application Towards Evolutionary Constraint Discovery, Matthew Chak

Master's Theses

Large protein databases now make it possible to study short peptides across natural protein sequence space at unprecedented scale, but exhaustively counting k-mers across billions of protein sequences remains computationally difficult. This thesis develops an exact amino-acid k-mer counting method based on direct addressing, in which fixed-length amino-acid strings are encoded as base-20 integers and updated with a sliding-window recurrence. By avoiding key storage and collision resolution, this approach removes overhead inherent to hash-map-based methods when the k-mer space is sufficiently dense. A memory analysis shows when direct addressing is preferable to open-addressing hash tables, and expected-saturation calculations motivate its …

Characteristic Stress And Strain Optimization Of Cardiovascular Catheters With Laser-Cut Hypotubes Using Finite Element Analysis, Kyle E. Hirth

Master's Theses

Cardiovascular catheter systems rely on laser-cut hypotubes to balance flexibility and structural integrity required for minimally invasive surgical procedures.  Optimizing these mechanical characteristics remains a significant challenge.  This study aims to investigate the influence of key laser-cut geometric parameters on the mechanical performance of hypotubes through finite element analysis.

Commercially representative laser-cut hypotubes were modeled and a finite element model was developed.   Geometric design parameters were varied across a design space consisting of pitch values ranging from 0.006 in. to 0.018 in. and cuts per revolution (CPR) ranging from 2.5 – 4.5.  For each pitch and CPR combination, loading stiffness …

Aerodynamic Design And Structural Evaluation Of A Global Minimum Torque Inspired Multirotor Propeller, Zeke Bukovansky

Master's Theses

This thesis develops a repeatable design, CAD, aerodynamic postprocessing, structural screening, and manufacturing feasibility workflow for a 22-inch global minimum torque inspired multirotor propeller. Matched MIL and GMT geometries were compared at a 35 N, 4000 rpm static-hover operating condition using BEMT/XFOIL aerodynamic postprocessing, with diameter, blade count, chord distribution, airfoil schedule, and target thrust held constant. The final modeled comparison predicted a modest 1.5% reduction in torque and shaft power for the GMT case while maintaining the same thrust target. CAD construction, MATLAB reduced-order beam model, Abaqus screening, and manufacturing planning were used to identify geometry level structural and …

A2s Uplink Latency Minimization For Wildfire Monitoring Systems Using Mbse And Stochastic Modeling, Luis Giovanni Wang

Master's Theses

Wildfire response depends on how quickly a detection reaches the people who act on it, and the slowest remaining step is often the link that carries an alert from a remote sensing platform to a satellite. This thesis models the latency of that link, the Air-to-Space uplink, for a wildfire-monitoring UAV that carries a Starlink terminal and sends an ALERT packet to a serving Low Earth Orbit satellite. The uplink is difficult to predict because both the UAV and the satellite move, and because the wildfire environment degrades the channel at the moment the data matters most.

The thesis uses …

Design And Reliability Analysis Of A Radiation-Tolerant On-Board Computer System For Martian Surface Missions, Jack Ryan

Master's Theses

Space environments present complex challenges for electronic devices, perhaps most notably in the form of radiation effects; the natural protections provided by Earth’s atmosphere and magnetosphere are largely absent in deep space and extraterrestrial environments, making single-event effects (SEE) a critical concern. Although radiation-hardened components offer near-immunity to SEE, they possess tremendous drawbacks in both cost and performance. To circumvent such issues, this thesis investigates the feasibility of leveraging a commercial-off-the-shelf (COTS) device, the AMD KRIA K24 system-on-module (SOM), for use in Martian surface missions.

Detailed models were used to predict SEE rates in the system, and system-level fault tree …