Digital Commons Network^™

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 …

`Youdrawitr`: Integrating Interactive Graphical Testing Into The `Ggplot2` Ecosystem, Alisa Krasilnikov

Master's Theses

`youdrawitR` is an R package inspired by the New York Times ‘You Draw It’ series, where readers are invited to sketch their own predictions before seeing the actual data. In a similar spirit, `youdrawitR` allows users to draw predicted values directly onto statistical graphics, creating a more engaging way to study how people interpret visual patterns. Earlier versions of the tool required knowledge of JavaScript D3 to extend or adapt the package, which created a barrier to entry for many statistical researchers. Further, the package was limited in scope, supporting only scatterplots. The redesigned `youdrawitR` builds on the familiar `ggplot2` …

Integer Quantization And Embedded Deployment Of Cnn Star Trackers For Cubesats, Meora R. Giusiano

Master's Theses

A star tracker determines spacecraft orientation by photographing the star field, detecting stars in the image, matching them against a catalog, and computing the rotation between observed and cataloged directions. Convolutional neural networks (CNNs) have been proposed as replacements for the detection and centroiding stage, offering improved sub-pixel accuracy and recovering faint stars that classical thresholds lose to stray light and sensor noise. The improvement comes at higher computational cost; the PolySat systemboard targeted in this work lacks the floating-point hardware these networks assume.

This thesis closes the gap between floating-point desktop evaluation and embedded integer deployment. Nine encoder-decoder CNN …

Evaluation Of Solar Reflective Pigments For Use In Direct-To-Metal Coatings, William J. Diment

Master's Theses

Solar reflective coatings offer a promising strategy to mitigate the urban heat island effect by reducing absorption of near-infrared solar energy. This thesis project investigates the feasibility of incorporating near-infrared reflective pigments into waterborne direct-to-metal (DTM) latex coating systems while maintaining acceptable color comparison characteristics and coating performance. An all acrylic latex DTM formulation with titanium dioxide as the sole pigment was prepared and tinted with a variety of conventional and solar reflective commercial colorants across the yellow, red, blue, and green color ranges. Coatings were evaluated for solar reflectance, CIELAB color, gloss, contrast ratio, rheological behavior, accelerated ultraviolet weathering …

What Makes A Modern Attention Implementation?, Brian H. Slonim

Master's Theses

Since the seminal assertion by Vaswani et al. in 2017 that “Attention Is All You Need,” transformer models have risen to ubiquity due to their ability to learn extremely complex patterns from sequence data, culminating in the unprecedented generative capabilities of large language models. These models’ strength lies in their scale: hundreds of millions (e.g., BERT-LARGE) to billions or trillions of learned parameters. Running inference with these models, let alone training them, would be intractable without significant innovations in the hardware and software that support them. This need has driven an enormous demand for GPU compute and associated software ecosystems, …

High-Resolution Queries, Low-Resolution Context: Scaling Vision Transformers With Asymmetric Spatial Reduction, James M. Dwyer

Master's Theses

Vision Transformers (ViTs) have demonstrated great performance on image classifica tion benchmarks, however, the quadratic complexity of the self-attention mechanism with respect to sequence length limits their scalability to higher resolution inputs. The attention score matrix grows as O(N2) in both compute and memory, where N is the number of patch tokens, making ViTs computationally expensive and memory intensive for applications that require real-time inference or operate under resource constraints.

This thesis investigates whether the key and value sequences of the self-attention mechanism can be compressed using the local spatial structure of the image — while keeping queries at full …

Development Of A Computer Vision Based Rendezvous And Docking Test Platform, David T. Forbes

Master's Theses

This thesis presents the work completed in the development and testing of a low-cost modular sensor package capable of rendezvous and docking by providing a vehicle with relative navigational commands. These navigational commands are created using relative localization data gathered and processed onboard the sensor package, with validation, in post-processing, against global localization data. This research aims to reduce the cost of smaller autonomous vehicles by removing the need for custom control units, as its modular nature will allow it to be adapted to many different systems and vehicles. Discussed within this thesis is the rapid prototyping, development, and testing …

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 …

Computer Vision Methods For Detecting Counterfeit Usd Bills, Tyler W. Jones

Master's Theses

This thesis addresses the global challenge of counterfeit paper currency by proposing a classical computer vision framework for distinguishing genuine United States Dollar (USD) bills from counterfeit ones using image data. In contrast to existing approaches that rely on a large number of easily reproducible visual features, this work prioritizes the detection of a single, robust security feature: the ultraviolet (UV) reactive security strip embedded in genuine USD bills of denominations $5 and above. By focusing on a feature that is inherently difficult to replicate, the proposed method reduces the likelihood of counterfeit bills being misclassified as genuine.

The system …

Effect Of Viscoelastic Materials On Laminated Composite Beams For Vibration-Sensitive Automotive Enclosures, Nathan D. Neugeboren

Master's Theses

This study evaluates high-damping composite laminates for vibration-sensitive automotive components, with emphasis on motorcycle instrument clusters, the dashboard that houses the speedometer, indicator lights, and other rider information. Cantilever beam specimens were used as simplified test articles to compare analytical Euler-Bernoulli beam predictions, Autodesk Nastran finite element analysis, and sine-sweep experimental measurements. Metallic beams were first tested to validate modeling assumptions, FEA setup, and laboratory procedures. Analytical and FEA natural frequencies agreed within 0.6 % for ideal bonded metal beams, establishing a baseline for modal prediction. The method was then extended to carbon fiber, fiberglass, Kevlar, and hybrid laminates, with …

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 …

Spaceotter: A Floating Spacecraft Simulator Air Bearing Vehicle For Hardware-In-The-Loop Experiments And Research, Alexander Debartolo

Master's Theses

Growing interest in nanosatellites has increased demand for accessible ground-testing methods, which have historically been expensive and restricted. Floating Spacecraft Simulators (FSS), built around Air Bearing Vehicles (ABVs), address this gap by approximating a zero-gravity, friction-minimized environment suitable for testing spacecraft control systems, robotics, and propulsion on the ground.

This thesis presents the design, realization, and initial performance characterization of the Space Optically Tracked Testbed for Experiments and Research (SpaceOTTER) ABV, developed for the Cal Poly Space Robotics Lab. SpaceOTTER is the first step toward emulating the 3 degree of freedom (3-DOF) planar dynamics of a simulated spacecraft and is …

Design And Evaluation Of An Assistive Powered Hand Orthosis For Grasp Activities For People Post-Stroke, Sydney Alexander

Master's Theses

After suffering a stroke, many survivors experience physical disability that affects their ability to complete daily tasks using their hands. Physical therapy is often pre scribed to people post-stroke, but is not fully effective at restoring hand function. The goal of this project was to design and fabricate an assistive device for people post-stroke to help with grasp and release. The device was designed to address com mon shortcomings of existing similar devices. State of the art devices in this domain were investigated to determine a set of design improvements. A novel motor-actuated hand orthosis was designed to decrease weight, …

When Agents Spend Watts: Measuring Performance-Energy Trade-Offs In Agentic Ai Systems With Agenticbench, Logan J. Barker

Master's Theses

Agentic AI systems increasingly transform a single user request into a multi-step workflow of reasoning, tool use, retries, and framework coordination. Standard benchmark reporting emphasizes task accuracy, but this can hide the latency and energy-related cost of producing an answer. This thesis presents AgenticBench, a modular harness for evaluating agentic AI systems with task performance and execution-cost signals recorded together. AgenticBench integrates benchmark-owned scoring, framework adapters, deterministic task selection, energy profiling, SQLite persistence, and Pareto-style analysis. The main campaign evaluated an 84-cell matrix across four models, three agent frameworks, and six benchmarks on a Windows workstation with an NVIDIA RTX …

Investigating The Structural Barriers And Opportunities For End-Of-Life Management Of Agricultural Plastic Waste Within California's Strawberry Industry, Rory M. O'Toole

Master's Theses

Agricultural plastic waste (APW) accounts for a significant and growing share of global plastic pollution, yet no study has documented how APW management functions across a specific crop system from production through end-of-life (EOL). This thesis addresses that gap by examining the structures and valuations that shape current EOL management of plastic mulch (PM) and drip tape (DT) in California's strawberry industry, one of the nation's most plastic-dependent crop systems. Drawing on an ethnographic approach that included 27 semi-structured interviews with stakeholders, as well as site visits, this study traces how APW is produced, valued, and discarded within a structurally …

Efficient Mathematical Modeling And Synthesis Of Realistic Musical Instrument Sounds, Andrew Chookaszian

Master's Theses

This thesis develops and evaluates a compact parametric additive synthesis model for isolated musical instrument tones. The method analyzes a single-note recording, estimates its fundamental frequency, extracts harmonic amplitude and frequency behavior, and stores the sound as a reduced set of interpretable parameters. These parameters include the note duration, pitch, per-harmonic amplitude envelopes, phase information, and amplitude- and frequency-modulation vibrato parameters. The stored model is then used to resynthesize the tone without directly using the original audio waveform.

The model was evaluated using synthetic signals, real instrument samples, objective error metrics, storage comparisons, pitch and duration modification tests, and listening …

Object Detection And Classification For Man-Made Structures To Aid In Search And Rescue (Sar), Mio A. Nakagawa

Master's Theses

This project explores the use of various object detection and classification models to identify permanent man-made structures, specifically cell towers, water towers, watch towers as well as its corresponding shadows (attributes), from aerial imagery. The goal is to evaluate those models and test the feasibility of current models to detect man-made structures in aerial images, in an effort to support search and rescue operations as well as update network infrastructure databases. Multiple object detection models, as well as classification models, including YOLOv8 and VGG19 are implemented and trained on annotated aerial images to determine the presence or absence of man-made …

Prototype X-Band Front End Upconverter & Transmitter With An Integrated Pll, Mont Ziadoon Murad

Master's Theses

In recent years, there has been growing interest in high-speed communication for small satellites. Achieving higher communication speeds will enable any experimental CubeSat to conduct experiments at higher rates and allow further research into SAR and deep-space exploration. At Cal Poly, the CubeSat Lab has mainly operated at 9600 baud and utilized the Ultra High Frequency (UHF) amateur radio band. While it has proven itself resilient, the UHF band lacks the infrastructure to support higher-bandwidth communication systems. To address this gap, this work presents a prototype space-side downlink RF front end comprising an upconverter, a power amplifier (PA), and a …

Challenges And Opportunities Of Mastery-Based Learning: A Student-Centered Analysis In An Upper Division Programming Languages Course, Parshana Sekhon

Master's Theses

Traditional grading structures in computer science courses reward performance on a few high-stakes assessments that may not accurately reflect a student’s mastery of concepts. Mastery-Based Learning (MBL) offers students multiple opportunities to demonstrate understanding through iterative feedback and reassessment, promoting their persistence and self-regulation. However, MBL can promote student behaviors like procrastination, “minimal effort” attempts, or de-prioritizing the course in favor of other courses with inflexible deadlines, which may undermine its effectiveness. This case study investigates how students navigated MBL in an upper-division computer science course at Cal Poly in San Luis Obispo. The course explores the fundamentals of programming …

Scorespeak: An Agentic System For Natural Language Control Of Musical Scores, Nathan S. Lim

Master's Theses

With the recent popularization of large language models (LLMs), natural language has become one of the most accessible and powerful ways for people to interact with creative tools. Although they have become common in mainstream domains like image and audio editing, there is currently no robust AI-based system that can reliably turn free-form language into edits for symbolic musical scores. This gap represents a missed opportunity to improve human workflows for creating and editing sheet music, but it is also a fundamental limitation for other agentic music systems; without a robust mechanism for translating free-form language into structured scores, AI …

Hamster: Hybrid-Actuated Mobile Spherical Terrain Exploration Rover, Winnie Gao

Master's Theses

The expansion of space exploration to increasingly challenging planetary environments requires mobility systems capable of extreme traversal capabilities and operational reliability. This thesis presents the design, development, and testing of a low-cost Hybrid-Actuated Mobile Spherical Terrain Exploration Rover (HAMSTER) intended for use on a planetary surface exploration mission. HAMSTER uses a pendulum-based actuation method for steering and an actuated internal shaft to propel the vehicle forward. The internal structure includes a two-tiered central case composed of the navigation control module, accelerometer, motor controller, primary DC motor, battery, voltage regulators, Raspberry Pi, pendulum servo motor, and drive shafts. Additive manufacturing through …

Design And Implementation Of An Embedded Control System For The Cal Poly Spacecraft Attitude Dynamics Simulator, Neil Mahesh Bedagkar

Master's Theses

This thesis presents the development of a cascaded reaction wheel control system for Cal Poly's Spacecraft Attitude Dynamics Simulator. This work considers system architecture, empirical modeling, high-fidelity simulation, embedded firmware, hardware integration, and experimental characterization. In discrete-time simulation, it is shown that nonlinear direct model reference adaptive control (NDMRAC) enables a nonlinear, partially known plant with realistic actuator dynamics to track the response of a canonical second-order transfer function, with settling time within 4.67% and percent overshoot within order of magnitude of the second-order response. In hardware, the feasibility of a cascaded reaction wheel control architecture is experimentally demonstrated, achieving …

Trustworthy Intelligence Fusion For Search And Rescue: Designing Grounded And Secure Multi-Agent Ai For Mission Decision Support, Yayun Tan

Master's Theses

Search and rescue (SAR) operations require teams to integrate uncertain information under severe time pressure. Large language model (LLM)-based multi-agent systems (MAS) can support decision-making, but they also risk producing hallucinated outputs and processing unreliable or malicious data. This thesis addresses these risks through three linked studies. First, it proposes a modular eight-agent SAR MAS architecture that reflects the structure of real SAR missions by assigning specialized roles to different agents. Second, it introduces a post-hoc probabilistic verification framework that checks LLM agent outputs against a probabilistic knowledge graph built from historical SAR incidents.  Third, the thesis examines indirect adversarial …

Empirical Comparsion Of Traveling Salesperson Approximation Algorithms, Shayan Daijavad

Master's Theses

The traveling salesperson problem deals with optimizing the route a traveling sales- person might take to visit a set of places exactly once and return back to their starting point. The problem is NP-hard, and it is hard to approximate in general, but special cases have many approximation algorithms, which come with tradeoffs. In this thesis we compare the runtime, approximation ratio, and overall implementation complexity of two approximation algorithms for the Euclidean version of the problem, a classical 2-approximation algorithm and the multifragment heuristic. We run both algorithms on randomly generated point sets and real world data from TSPLIB. …

Uncertainty-Weighted Fusion Of Sensor And Monocular Foundation-Model Depth For 3d Gaussian Splatting In Indoor Rgb-D Capture, Brandon S. Howell

Master's Theses

Depth-supervised 3D Gaussian Splatting can improve scene geometry in indoor RGB-D capture, but noisy commodity depth measurements can also reduce rendered image quality. This thesis studies that trade-off in room-scale indoor reconstruction using two complementary depth sources: Kinect-class RGB-D sensor depth, which is metric but noisy and incomplete, and Depth Anything 3 (DA3) monocular depth, which is dense and meter-valued but not calibrated to the sensor or laser-reference geometry. 

The proposed method constructs a per-pixel depth supervision target by inverse-variance fusion of the sensor depth and the monocular depth prediction. The fused target is used to train a depth-supervised 3D …

Characterization Of The Thermally Driven Red Hue Effect In Coated And Uncoated Concrete Systems: Implications For Post-Fire Assessment In Wildland Urban Interface Communities, Juan C. Palominos Jr

Master's Theses

The increasing frequency and intensity of Wildland-Urban Interface (WUI) wildfires, such as the destructive 2025 Pacific Palisades Fire that destroyed over 6,000 structures, have underscored the urgent need for rapid post-fire safety assessment methodologies. This study sought to quantitatively characterize the Thermally Driven Red Hue Effect (TRHE), a unique, irreversible color shift observed in architectural coatings and concrete substrates, to determine its reliability as a permanent visual record of thermal exposure. Concrete substrates were formulated with three distinct coarse aggregates: gold granite (14.7% Fe), red cinder (22.4% Fe), and green rock (33.6% Fe) and coated with a 20 PVC waterborne …

Space Quacker Advanced Development (Squad): Lora Modulation On A Leo Cubesat Mission For Evaluation Of 916 Mhz Uplink, Samantha Brunton

Master's Theses

The LoRa Modulation format was developed by SEMTECH in 2018 and has revolutionized terrestrial Internet of Things (IoT) networks. LoRa (Long Range) has been successfully demonstrated as a long-range, low-data-rate communication modulation format and packet protocol for low-power terrestrial applications. LoRa offers low power consumption, low cost, robust signal sensitivity, and long communication range. Recently, interest has grown in using LoRa communication in Low Earth Orbit (LEO) satellite systems, especially for global IoT connectivity. Previous studies have investigated the theoretical feasibility and simulated the performance of LoRa satellite communication. Companies such as Lacuna Space have demonstrated the practical potential of …

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 …

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), …