Digital Commons Network^™

How Human Vs. Ai Chatbots Support Psychological Needs Of Students, Tymon T. Vu

Master's Theses

AI auto graders and virtual assistants are increasingly prevalent in educational set- tings. Although current literature demonstrates that AI chatbots can positively im- pact student motivation, there is little definitive evidence exploring whether these systems can replicate the effective motivational methods used by human teachers. Thus, in this experiment, we investigate how the perception of the identity of a tutor (AI versus human) impacts the psychological needs of students. 27 undergraduates taking introductory computer science courses were asked to explain code in plain English (EiPE). Participants received feedback from two tutors in within-subjects fashion: one human and one labeled as …

The Effects Of Maceration And Enzymes On The Chemical Characteristics Of Hard Apple Cider, Manou De Pelsmaeker

Master's Theses

The purpose of this study was to analyze the effects of maceration and pectinase enzymes on the base chemical, polyphenolic, and volatile characteristics of cider. The apples (Fuji) were milled and macerated for 0, 4, 12, 24, or 36 hours, both with and without an enzymatic pectinase addition. While base chemical characteristics such as sugar content and ABV were unaffected, the acidity of cider was influenced maceration and enzymes. Extended maceration time resulted in lower concentrations of malic acid, and enzymes resulted in a lower pH compared to the control. Polyphenols were extracted during maceration time, resulting in higher concentrations …

Deep Learning For Affect Recognition: A Comparative Study Of Physiological Sensor-Based And Facial Image-Based Approaches, Ravi Panchal, Ravi Panchal

Master's Theses

This thesis investigates deep learning approaches for affect recognition using wearable physiological signals and facial image data. The sensor-based component evaluates stress and affect recognition on the WESAD dataset using wrist-based physiological windows and examines multiple temporal modeling strategies, including convolutional, recurrent, hybrid CNN-LSTM, attention-based, ensemble, and time-frequency approaches.

The image-based component evaluates hard-label facial expression recognition on AffectNet+ using pre-trained ResNet-50, EfficientNet-B3, and ConvNeXt-Tiny architectures across Easy, Challenging, and Difficult subsets representing different levels of expression ambiguity.

Experimental results show that the proposed Multi-Branch Attention CNN-BiLSTM (MBA-CNN-BiLSTM) model achieves the strongest wearable stress- and affect-recognition performance among the evaluated …

Movement And Space Use Of Weaned Northern Elephant Seal (Mirounga Angustirostris) Pups During Their First At-Sea Foraging Migration, Katie Saenger

Master's Theses

The northern elephant seal (Mirounga angustirostris) is a marine mammal known for engaging in long foraging migrations at sea. Adult male northern elephant seals follow pathways along the western coast of North America towards Alaska and adult female northern elephant seals follow pathways to open ocean in the North Pacific. However, there is little information on weaned northern elephant seal pup foraging behavior during their first foraging migration. This lack of knowledge is significant because northern elephant seals have a mortality rate of >50% in the first year. This project aimed to better understand the at-sea migratory movement …

Reproducing And Evaluating Charger Surfing: Robustness Of Smartphone Charging-Line Side-Channels, Colby M. Watts

Master's Theses

Smartphones are frequently connected to external, untrusted charging hardware, creating opportunities for side-channel attacks that do not require malware or direct access to device data. Charger Surfing, a recently proposed charging-line power analysis side-channel attack, reported high accuracy in inferring touchscreen input from voltage measurements collected from a smartphone’s charging cable; however, the reproducibility and robustness of these results under different conditions remain unclear. This thesis presents an independent replication and evaluation of Charger Surfing, including the development of an end-to-end data collection pipeline consisting of a modified charging cable, oscilloscope-based recordings, custom Android app, automated trace processing, and convolutional …

An Evaluation Of Road Network Structure As A Predictor Of Traffic Volume, Colin M. Mcdonald

Master's Theses

This thesis evaluates the relationships between various graph theory metrics and taxi traffic volume for the cities of San Francisco, California and Porto, Portugal. We also evaluate a modified betweenness centrality metric which incorporates the count of distinct origin-destination pairs from the taxi data as the weight function. This thesis extends a paper by Pengyao Ye, Bo Wu, and Wenbo Fan by reducing circularity through a temporal train-test split and by comparing both line-graph and primal-graph formulations of betweenness centrality.

We found that past traffic volume is almost perfectly correlated with future traffic volume and that the modified betweenness centrality …

Sustainable Management Of Soilborne Pathogens In Strawberry Production Through Host Resistance And Sanitation Practices, Maria G. Alvarez Arredondo

Master's Theses

Strawberry production in California is significantly impacted by soilborne pathogens that reduce plant productivity and increase management costs. This research addressed management of these pathogens through two independent approaches: evaluation of host resistance in strawberry cultivars and assessment of sanitation practices for reducing pathogen movement between fields.

Macrophomina root rot, caused by Macrophomina phaseolina, was evaluated over two growing seasons (2024–2025 and 2025–2026) using field trials at California Polytechnic State University, San Luis Obispo. In Year 1, disease incidence varied widely among genotypes, with mortality ranging from 1.3% to 88.8% and an average mortality of 26.4%. Area under the …

Bowl-O-Matic, Nathan Lin, Luis Torres, Jill Worthington, Aiden Foote

Mechanical Engineering

Adaptive physical education presents the unique challenge of accommodating individuals with diverse physical and cognitive abilities. Instructors and program designers must often integrate specialized equipment, fixtures, or features to ensure activities remain safe, inclusive, and user-friendly. Beyond accessibility, adaptive physical education highlights the importance of empowerment— enabling every participant to experience personal growth, confidence, and connection through movement. Friday Club, a local San Luis Obispo program supported by Cal Poly’s Kinesiology Department, embodies these values by providing adaptive physical activities that promote health and well-being for individuals with varying abilities. One of the most popular and regularly held activities is …

Matlab Shake Table Control And Data Acquisition System, Abigail Austin

Architectural Engineering

The College of Architecture and Environmental Design’s (CAED) seismic laboratory shake table is used for earthquake engineering education and experimental testing. However, the existing control system is outdated and difficult for students unfamiliar with the system to operate. The objective of this project was to develop a MATLAB-based control and data acquisition application to simplify shake table operation and improve accessibility, of both operation and output, for student users.

The developed application imports earthquake acceleration records, scales the input motions to the operational limits of the shake table, and executes the desires motion through the existing hardware system. Experimental data …

Electrically Evoked Emg Decomposition Using The Perturbative Generalized Series Expansion, William R. Walker

Master's Theses

Electrically evoked electromyography records the muscle's response to nerve stimulation and has been used for clinical assessment of neuromuscular function, as well as treatments such as functional electrical stimulation or stroke rehabilitation. In every muscular contraction, an electrical signal is generated. These signals come from the summation of simultaneously recruited motor units, enabling decomposition techniques to reveal information about motor unit recruitment.  By improving the ability to decompose and analyze these signals, clinical treatments involving neuromuscular electrical stimulation can be optimized and better understood. Much of the research on EMG analysis focuses on voluntary EMG, leaving a gap in the …

Vision-Guided Motion Planning For Autonomous Catch With A Robotic Arm, Kayla Go-Oco, Ashik K. Islam, Raegan Gritzmacher

Electrical Engineering

Modern robotic systems are often evaluated using static and highly controlled tasks, such as pick-and-place demonstrations, which do not fully represent the uncertainty and adaptability required in real-world environments. A major challenge in robotics research is enabling robotic systems to perceive, track, and respond to dynamic objects in real time while maintaining accurate and reliable motion control. This project addresses these challenges by developing an autonomous robotic platform in which an OpenMANIPULATOR-Y robotic arm detects, tracks, and attempts to catch a moving tennis ball using a vision-guided control system. The system integrates YOLO-based object detection with an Intel RealSense D455 …

Content Warning, Editorial Board

Intertidal

No abstract provided.

Aged 539 Internship Report: Cal Poly Rodeo Media And Marketing, Anna Grace Durham

Agricultural Education: Graduate Internship Reports

This internship report examines the role of media and marketing within the Cal Poly Rodeo Program and highlights the integration of leadership, athlete development, and strategic communications in a collegiate athletics setting. Serving as the Media Manager for Cal Poly Rodeo, the internship focused on strengthening the program's digital presence, enhancing brand identity, and increasing community engagement, particularly surrounding the 2026 Poly Royal Rodeo. Through collaboration with University Administrators, the Officer Team, sponsors, and external media partners, comprehensive marketing campaigns were developed and implemented, resulting in significant increases in social media reach, audience engagement, and ticket sales. The project included …

Project Strata, Hobbs Hegedus, Antony Chen, Adrian Scancich, Peter Constantine Psefteas, Ryan Kreis Roth, Jack Douglas Mitchell

Mechanical Engineering

Project STRATA is a lunar sample acquisition and storage system developed in support of NASA’s Artemis mission objectives and the 2026 NASA RASC-AL competition. The overall mission concept utilizes a dual-rover architecture consisting of HARVEST, a sample collection rover, and SILO, a storage rover designed to preserve and organize lunar ice-regolith core samples collected from permanently shadowed regions (PSRs) near the lunar south pole. These regions contain scientifically valuable volatile-rich materials but present significant challenges due to extreme cryogenic temperatures, abrasive lunar regolith, and the absence of solar energy.

This report is a collection of all major work from the …

Peltier-Based Hydration Accumulation Terminal (P.H.A.T.), Jenner Mucher, Ethan Pace, Renee Robolledo, Sabrina Luo, Taehoon Lee, Tarsem Pal

Mechanical Engineering

The objective of this project is to design an innovative potable water dispenser capable of safely delivering hot, ambient, and chilled water on demand for human lander missions. The system will support astronauts’ hydration and food rehydration needs while minimizing mass, power, maintenance, and contamination risks in microgravity and partial-gravity environments. Current spacecraft dispensers, such as the International Space Station (ISS) system, provide only heated water and have limited temperature control, cleaning accessibility, and microbial resilience. Building on NASA heritage designs and lessons learned from the ISS Potable Water Dispenser, this project advances a lighter, simpler, and more energy-efficient concept …

Mass - Modular Acoustic Suppression System, Julia Megargle, Michael A. Milner, Lucas Kaemmererer, Jonathan Corvera, Gabriel Choi, Emmi Cayer

Mechanical Engineering

The Modular Acoustic Suppression System (MASS) is a mass tuned damper that reverberates a membrane atop a cavity to absorb select acoustic frequencies produced by the Environmental Control and Life Support Systems (ECLSS) within NASA's Artemis Human Lander. The height of the reverberation chamber is adjusted to mitigate a range of varying tonal frequencies within the human lander.

Mechanical Jump Rope, Mary Harrington, Naail Lalani, Lucas Nathan, Guy Kalach

Mechanical Engineering

This Mechanical Jump Rope Senior Project was performed by four Mechanical Engineering students. This project was for the Cal Poly Kinesiology and Public Health Department, to be used by Cal Poly Friday Club, a collaboration between the San Luis Obispo Special Olympics and Kinesiology students. The purpose of the project was to allow those with different mental and physical abilities to learn and practice the timing of a jump rope at slow and adjustable speeds.

Cardiac Twitch Force Measurement System, Tara Hoffman, Sebastian Carrascal Gómez, Julian Macdonald

Biomedical Engineering

The goal of this project is to develop a low-cost and accurate force measurement system and method of measurement to be used in the testing of grown cardiac tissue samples. The primary stakeholder in this project is Dr. Luke Perreault, a biomedical engineering professor at California Polytechnic State University San Luis Obispo who is studying grown cardiac tissue rings, and any of his student lab personnel. Other stakeholders include other researchers in the tissue engineering field who require a similar form of testing to the methods developed in this project.

This document will introduce the identified problem and background as …

Design And Implementation Of An Intelligent Wearable Health Monitoring System Using The Shimmer Platform, Christopher Tu, Rafael Martinez

Computer Engineering

This report goes over the wearable health monitoring system that we built that uses an activity classification system to tell what you are doing real time. We used a Shimmer3 sensor to collect accelerometer data and streamed it via Bluetooth to our laptops where we processed the data and ran a machine learning classifier to detect if someone is resting, walking or running. We collected our own data to train the Random Forest classifier that we used from scratch and ended with 98% accuracy. The system has a live dashboard implemented into it that shows sensor data and the current …

Autonomous Vision-Based Litter Collection Rover, Dante Michael Benedetti, Benjamin Scott Tavares, Nathan Heil

Electrical Engineering

This report documents the design, implementation, and testing of an autonomous litter-collection rover developed as a Senior Project Design Lab (EE 460/463/464) at California Polytechnic State University. The rover integrates autonomy, computer vision, embedded real-time control, mecanum-wheel omnidirectional mobility, and a two-degree-of-freedom robotic arm to detect, approach, and collect small ground-level litter such as bottles, wrappers, and paper fragments.

The system uses a two-layer compute architecture: an NVIDIA Jetson Orin Nano running ROS 2 for perception, SLAM, and path planning, paired with an STM32L4A6ZG microcontroller for real-time motor control and odometry. The robot is built on a multi-level aluminum frame …

Elevate Grill, Brady Alexander

Electrical Engineering

The Elevate Grill Senior Project is a Santa Maria style grill with an electrical lifting/lowering mechanism and temperature sensor feedback. The grill allows for a dynamically controlled cooking surface, able to be automatically set or manually set by the user. The grill’s user interface informs the user about the temperature in different zones on the grill and alerts the user when the target temperature is hit. Additionally, the user can program preset temperature ranges and apply them to the grill’s control system. The system incorporates safe failure modes in the event of a power outage and also allows the user …

Pcb Design For Place Cells Vlsi Chip, Gavin Reaksecker, Alex Krier, Joshua Lin

Electrical Engineering

This project presents the design and implementation of a 2 layer test-bench printed circuit board (PCB) for evaluating the functionality of a custom 40-pin VLSI integrated circuit. The objective is to create a reliable and portable platform capable of supplying configurable bias voltages, generating variable input signals, and monitoring both analog and digital outputs. The board integrates adjustable bias networks using potentiometers, digital and analog buffering stages, and optional battery supply operation. The VLSI device under test is mounted in dual-in-line (DIP) sockets to enable rapid replacement and repeated characterization. Dedicated test points are incorporated throughout the PCB to facilitate …

Solving Linearly Constrained Quadratic Programs Using Field Programmable Analog Arrays, Tyler Wynn, Alonzo Arroyo

Electrical Engineering

This paper presents a field-programmable analog array (FPAA) implementation for solving linearly constrained quadratic programs (LCQPs) directly in the analog domain. The solver is based on a continuous-time primal-dual control architecture with integral action, anti-windup compensation, and a piecewise-linear nonlinearity for enforcing affine inequality constraints. A switched-capacitor implementation using three AN231E04 FPAAs is developed, and coefficient scaling methods are introduced to keep internal and output signals within the voltage limits of the hardware. A global scaling factor is used to reduce internal signal excursions, while solution-space scaling is shown to modify the implemented optimization coefficients and alter the local closed-loop …

Autonomous Rover Solar And Battery Management System: Team B, Karla Jazmin Lira Gonzalez, Paige Ambriz, Kunj Shah, Elhom Delasa Sheykhi

Electrical Engineering

This project focused on the software and printed circuit board (PCB) integration for Poly1Rover’s battery management system (BMS). Poly1Rover is a student organization dedicated to building a low-cost autonomous rover designed to operate on Mars. Since solar availability, temperature, and other conditions on Mars vary, the rover requires a reliable battery management system that accurately monitors battery health and status. This team’s work included the communication and control side of the BMS. The subsystem was designed around the Renesas ISL94202 battery monitor and the MSP430 controller. Battery information was read from the ISL94202 registers through I2C communication, converted from raw …

Estimation And Control For Physical-Ai Aerial Robots, Joshua S. Crain

Electrical Engineering

This project investigates the modeling, control, and state estimation of a Crazyflie 2.0 quadrotor using both a custom nonlinear simulation and the NVIDIA Isaac Lab robotics simulation framework. A twelve-state rigid-body dynamic model was developed to represent the translational and rotational motion of the vehicle, and classical cascaded PID control was implemented for position and attitude stabilization. To improve state awareness in the presence of sensor noise, Kalman Filter (KF) and Extended Kalman Filter (EKF) algorithms were integrated for state estimation. Initial controller development and verification were performed using a custom MATLAB/Python simulation environment based on numerical integration of the …

Stella: A Narrative Exploration Of Artificial Intelligence, Grief, And Human Consciousness, Alyssa Grace Gerardo

Computer Science and Software Engineering

STELLA is a narrative-driven 2D puzzle adventure game developed in Unity that explores themes of grief, memory, human connection, and artificial intelligence. Players assume the role of Luna, a young woman searching for a missing friend who becomes trapped within a mysterious garden overseen by a mysterious entity known as STELLA. Through exploration, environmental storytelling, dialogue, and a series of puzzles, players uncover a deeper narrative centered on loss, obsession, and the pursuit of artificial immortality.

Chemical And Sensory Consequences Of Oxidative And Reductive Handling Of White Wines, Amelia Pargellis

Master's Theses

In the 2024 and 2025 vintage four experiments were performed each with a different varietal, namely Albariño, Grenache blanc, Loureiro, and Vermentino. These experiments investigated the effects of hyperoxygenation, reductive winemaking techniques, while monitoring the oxidation-reduction potential.

Albariño grapes were made following two juice protocols, control/reductive (Reductive Control) and oxidative (HyOx). Reductive Control received antioxidants (50 ppm SO₂, 160 mg/L ascorbic acid) and CO₂ blanketing, and HyOx underwent hyperoxygenation at approximately 700 mL/L/h of air for two hours through a stainless-steel sparging stone with 10-µm pores. Juice was cold-settled and racked. Reductive Control juice was split into …

Lesson Plan: Sr. Levadura (Mr. Yeast), Kali Elise Rye

World Languages and Cultures

This project addresses critical microbiology misconceptions concerning microbes and fermentation. Alongside Nuestra Ciencia’s lesson development team, this activity was researched and tested to demonstrate ideal fermentation conditions for yeast. In addition to the hands-on experiment, this project also required an interactive worksheet to be completed alongside the activity. With feedback from undergraduate students, researchers, and professors, the content was shaped to create an engaging, easily comprehensible activity that introduces microbiological concepts to students. As it has progressed, the Sr. Levadura (Mr. Yeast) activity has been implemented in two quarters of SCM 302 (Learn by Doing Lab) where over 400 elementary …

Hospital Bed Tray Table, Ava Mikeska, Sara Chamness, Samantha Kenney, Kaitlyn Ould

Mechanical Engineering

This project documents the design and development of a collapsible hospital bed tray table created through the Mechanical Engineering Senior Project program at Cal Poly, San Luis Obispo. The goal of the project was to reduce the floor space occupied by existing overbed tray tables while preserving the functionality, stability, and durability expected by patients, visitors, and healthcare staff.

The final design modifies a commercially available overbed tray table by incorporating a folding tabletop hinge mechanism and a telescoping base. The hinge allows the tabletop to lock in both the upright and stowed positions, while the telescoping base retracts to …

Smart Sleeve, Evan Abalos, Bright Jung, Owen Bowling, Wyatt Eberhart

Mechanical Engineering

Quantifying human arm muscle activity is essential for understanding human movements and helping individuals who suffer from motor or neurological impairments such as stroke or traumatic brain injuries. Today, these individuals, as well as clinicians, researchers, and athletes, face many challenges when using the traditional surface electromyography (sEMG) systems to monitor muscle activities, including complex setup, restricted mobility, discomfort, inconsistent placement of electrodes, and lack of accuracy. Therefore, a comfortable EMG sleeve device that accurately measures arm movement without interfering with daily tasks is needed, which the team will be designing, manufacturing, and testing as their senior project. In addition, …